Table of contents

This present volume contains the proceeding of the 2^nd Annual Conference of Science & Technology (Ancoset) 2020. In this year, the 2^nd Ancoset was virtually delivered through online platform due to Covid-19 Pandemic on November 28, 2020. This conference was organized by Universitas PGRI Kanjuruhan Malang and co-organized by Rumah Publikasi Indonesia.

Taking the theme of The Role of Science and Technology Application on Building Community Resilience during New Normal, we provided intellectual forum for students, researchers, lecturers, and practitioners. There are 221 papers collected which propose an insightful thought on the frontier knowledge about science and technology and its application. This conference opens an opportunity for scientific cooperation as well as international collaboration as it attended by almost two hundreds participants both across Indonesia and Asia.

We really appreciate all support given for the success of the 2^nd Ancoset 2020 and thus would like to express our gratitude to everyone who has taken part in this event:

• The scientific reviewers for helping authors come up with a good quality paper,

• The distinguished keynote speakers: Assoc. Prof. Sudi Dul Aji, M.Pd (Universitas PGRI Kanjuruhan Malang), Assoc. Prof. Dr. Massudi Mahmuddin (Universiti Utara Malaysia), Prof. Ida Hamidah, M.Si (Universitas Pendidikan Indonesia), Prof. Dr. Ade Gafar Abdullah, M.Si (Universitas Pendidikan Indonesia),

• Co-Host universities: Universitas Al-Ghifari, Universitas Hamzanwadi, Universitas PGRI Semarang, Institut Teknologi Nasional Malang, Universitas Ma Chung, Universitas Bhinneka PGRI, Universitas PGRI Adi Buana Surabaya, IKIP PGRI Jember,

• All presenters and participants, and

• The committee members for the commitment, effort, and hard work in accomplishing the conference and proceeding.

We wish you all a fruitful gathering and see you on the next conference.

List of The Editors, COMMITTEES are available in this pdf.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Type of peer review: Single-blind / Double-blind / Triple-blind / Open / Other (please describe)

A group of reviewers with good reputation of international publication were assigned to review the manuscripts of ANCOSET 2020 using Unikama Conference Submission System. Prior to the review process, all the reviewers were briefed by Prof. Ade Gafar Abdullah on a virtual meeting regarding the reviewing process. As many as 16 reviewers were then eligible in which each was sent 2 – 3 papers through the submission system. They were given two weeks to finish their review process and given a certain amount of incentive once they finish their task. After the deadline, the reviewed manuscripts were sent to the participants (authors) using the system through their personal account. The authors were given two weeks to revise their manuscripts and send them back to the committee using their account. Papers whose revision was in accordance with the reviewers' comments went into final editing process (paper template layout checking, proofreading, etc.) and those which need further revision went into the second round of review process. All the manuscripts and other required data were submitted to IOP after they passed final editing.

• Conference submission management system:

Unikama Conference Submission System

• Number of submissions received:

281

• Number of submissions sent for review:

243

• Number of submissions accepted:

221

Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100):

221/281 X 100 = 78.6%

• Average number of reviews per paper:

15

• Total number of reviewers involved:

16

• Any additional info on review process:

None

• Contact person for queries: ade gaffar@upi.edu

Utilization of coagulants with natural ingredients has been widely developed, the advantage of using biocoagulant is the availability of abundant material, easy to obtain it, from renewable materials, and low toxicity. This research compare chitosan clam bloodshells (Anadara granosa) coagulan and alum coagulan, to reduce concentration total chrome, nickel and turbidity in electroplating waste. The variations of coagulan, 300 mg/l and 600 mg/l, variation of the speed used is 150 rpm and 300 rpm. Results of the research, Alum and Chitosan can reduce the concentration of TSS, Nickel and Total Chrome. Alum can removel TSS by 93.75% at dose 300 mg/l, stirring speed of 150 rpm, Nickel by 32.49% at dose of 600 mg/l, stirring speed of 300 rpm, total Chrome removal of 64.09% at dose of 600 mg/l, stirring speed of 300 rpm. Coagulant chitosan TSS by 97.79% at dose 300 mg/l and 600 mg/l, stirring speed of 150 rpm, Nickel by 50,73% at dose of 600 mg/l, stirring speed of 150 rpm, the total chromium by 72.88% at dose of 600 mg/l, stirring speed of 150 rpm. Alum and chitosan coagulant the ability to neutralize the pH in accordance with the standard quality standard of electroplating waste, from 6.2 to 7.6.

Indonesia is a country known for its useful natural resources, especially for a health maintenance and treatment of diseases. Some of the plants that can be used as traditional medicine are kratom (Mitragyna speciosa Korth) and Senggani (Melastoma malabathrium L.). The purpose of this research was to determine the total phenolic content, total flavonoids content, and total tannins content in the ethanol extract of kratom stems and flowers using the UV-Vis spectrophotometric method. The comparator used in determining the phenolic content was gallic acid, for the flavonoid content was quercetin, and for the tannin content was tannic acid. The results of this study showed that the total phenolic content in the kratom stem extract was 23.59 mg/gram of extract, while in the senggani flower was 43.97 mg/gram of extract. The total flavonoid content in the kratom stem extract was 10.65 mg/gram of extract, while the senggani flower was 11.26 mg/gram of extract. Lastly, the total tannin content in the kratom stem extract was 17.99 mg/gram of extract, while in the senggani flower it was 13.74 mg/g extract.

Secondary metabolite compound is compound that have medicinal properties, cosmetics, dyes, fragrances. Secondary metabolite compound can be modified into one form of pharmaceutical dosage, namely cosmetic products. One of the cosmetic products is liquid soap preparation. Soap that can kill bacteria is known as antiseptic soap. Clove leaves (Syzygium aromaticum L. Merr. And Perr) contain eugenol compounds which have antiseptic properties. This study aims to determine the effectiveness of the ethanol extract of clove leaves as an antiseptic liquid soap preparation. The formulation of clove leaf extract with concentrations of 5%, 10% and 15% with HPMC concentrations of 1 gr, 2 gr and 3 gr. The liquid soap formulation of clove leaf ethanol extract was tested for organoleptic, pH, specific gravity, high foam and viscosity. The results of testing the quality of all liquid soap formulations meet the requirements according to the standards set by SNI. Based on the evaluation of this liquid soap preparation, the ethanol extraction preparation can be formulated into liquid soap preparations. After being tested for its antibacterial activity, Sedian Liquid Soap from Ethanol Extract of Clove Leaves has effectiveness as an antiseptic.

Sardinella lemuru is a small pelagic fish which is mostly caught in Java and Bali waters. It is important because of its high Omega-3 fatty acid. As pelagic fish that are found in relatively shallow waters and near the coast, it could be contaminated from the land. The purpose of this study is to analyse the mercury content of S. lemuru caught in three fishing ground in East Java (Prigi and Muncar) and Bali (Kedonganan). Fish samples were taken by random sampling and collected from November 2019 to March 2020 and analysed for mercury content using the Cold Rapoun Atomic Fluorescence method using the Atomic Absorption Spectroscopy (AAS) Shimadzu AA-6200. Furthermore, the Estimated Daily Intake (EDI) and Maximum Tolerable Intake (MTI) are calculated. The results showed that mercury concentration in S. lemuru were 0.938 ± 0.45 mg/kg and 0.58 ± 0.65 mg/kg for Kedonganan and Prigi, respectively. While, there is undetected mercury for Muncar fish samples. The mercury concentration identified are above the Indonesia standards (SNI and BPOM = 0.5mg/kg). Moreover, the EDI value was higher than Provisional Tolerable Daily Intake -WHO. The mean value of MTI is 0.121 mg/week. If fish contaminated mercury was consumed in one week exceeds the MTI value, the heavy metal could affect the human health.

The purpose of this research was to determine the effect of storage time at 5°C on the quality of yogurt with the addition of local Taro Starch as Stabilizer. The materials were used: fresh cow's milk, skim milk, starter and taro starch. The research method used was a laboratory experiment using a Completely Randomized Design (CRD) with different storage times at 5°C, namely: 5 treatments including: P1: 1 day, P2: 7 days, P3: 14 days, P4: 21 days, P5: 28 days. Each treatment was repeated 4 times so that 20 research units were obtained. The variables observed were the syneresis, WHC, pH, and total acid of the yogurt. Data were analyzed by one way Anova and followed by Duncan's multiple range test (DMRT). The results showed storage time at a refrigerator temperature of 5°C gave a very significant difference (P≤0.01) to the syneresis, WHC, pH, and total acid of the yogurt. Based on the research results, it can be concluded that the storage time of yogurt can last up to 21 days.

In order to investigate their crystalline structure conformations, several ratio combinations of polyethelene glycol (PEG)/cellulose acetate butyrate (CAB) were studied by Raman spectroscopy. PEG/CAB spectral features due to the composition dependence revealed the gradual transformation from crystalline PEG-like structure to the amorphous CAB-like structure as increasing the ratio of CAB. Bands appeared in the C-H stretching area of 3000– 2700 cm⁻¹ and C-H bending area of 1500–1400 cm⁻¹ clearly exposed the transition of the PEG to the CAB-spectral features with the transition point at about PEG/CAB (30/70). Band at 1737 cm⁻¹ in the C=O stretching area of 1800–1650 cm⁻¹ described the existence of a very weak hydrogen bond arise between PEG and CAB. In the C-O-C area of 1000–800 cm⁻¹, drastic spectral change suggested that the hydrogen bond interaction takes place in the back bone of PEG.

Digestive gland Achatina fulica is source of bioprospecting of glycoside hydrolases enzymes for many biotechnological and industrial processes. Nevertheless, there is limitation to discover novel enzymes. The functional-based approach analyzes the metagenomic library based on the genomic function of an organism used to look for new enzyme-producing genes. The aim of this study was to determine the chances of obtaining the novel genes for glycoside hydrolases from enzymes reservoir of digestive gland A. fulica through functional metagenomic method. The results showed that the total RNA concentration isolated from the digestive gland of A. fulica was 2,343.2 ng/uL. A total of 2 uL of total RNA has been used to construct the metagenomic library, so there are 4.69. 10¹⁰ - 1.87. 10¹¹ transcribed molecules from 1.17. 10⁹ - 4.68. 10⁹ genes. This is a great number of chances to acquire the novel glycoside hydrolase genes.

Meat floss or known as Abon (Indonesian) made from dried meat and has a fluffy texture similar to cotton coarse. The crude protein content of meat floss was less than 15%. Catfish (Clarias sp.) has rough fiber and does not contain many bones that are ideal for the main ingredients for meat floss. Catfish (Clarias sp.) cultivated from freshwater can be used as main ingredients for meat floss. To raise the economic value of meat floss, some use banana blossoms (Musa paradisiaca) as a filler. This study aims to determine the effect of banana blossoms as a filler and frying temperature on the chemical quality and organoleptic properties of catfish meat floss. The Method of this research is to make catfish meat floss with various banana blossoms and various frying temperatures. The method used is the analysis of variance or the factorial pattern of analysis of variance (ANOVA). The result showed the most preferred sample was the treatment sample with 60% banana blossoms filling and a frying temperature of 170 °C. The samples have the moisture content of 6,8%, the protein content of 14,91%, and fat content of 9,73%, as well as the preferred parameters of color, fragrant, flavor, and texture. The results showed that the use of banana blossoms as a filler in catfish floss improved the quality of shredded and has the potential to be used as a form of food product diversification.

Chili is one of potential vegetable due to its high demand and as an important source of nutrition. Hybrid chili has several advantages so it is beneficial to be cultivated. The purpose of this study is to examine the quality of several prospective varieties of large chili hybrids which will be released as new varieties. This research was conducted in Indonesian Vegetable Research Institute in 2019 at the Post Harvest Physiology Laboratory, West Bandung Regency, West Java. The materials used in the study were 3 chili variety candidates and 2 existing varieties that harvested in Lembang during rainy season. The study used randomized block design with 5 treatments and 5 replications. Physical parameters observed were weight, diameter, length, and texture. Chemical parameters include water content (gravimetric method), Total Soluble Solid (TSS), vitamin C (titration method), and ash content. Organoleptic test was carried out by 15 untrained panelists using scale from 1 (like extremely) to 5 (dislike extremely) in order to determine consumer acceptance of the freshness of chillies. The organoleptic tests were conducted on days 0, 4, and 7. The results showed Genotype number. 4 had weight, diameter and vitamin C close to the comparative varieties. Genotypes number 2 and 3 have quality parameters (color, shape, size, appearance, and freshness) preferred by consumers during storage until the 7th day at room temperature in Lembang area of West Java.

Acacia (Acacia mangium Willd) is a fast growing tree species that widely found in Indonesia. Acacia bark contains a number of secondary metabolites such as tannin, saponin and flavonoid that may inhibit the growth of undesirable microbes incuding the pathogenic ones. The purpose of this research was to evaluate the antimicrobial activity of tannin extract obtained from Acacia bark against common pathogenic bacteria species present in the gastro-intestinal tract of livestock, i.e., Salmonella typhimurium and Eschericia coli as Gram negative bacteria. The disc diffusion method was employed for assessing the antimicrobial activity of Acacia tannin extract. Treatments consisted of negative control (NC), positive control by using chloramphenicol (PC), Acacia tannin extract at two concentrations, i.e., 1% (AT1) and 2% w/v (AT2), and commercial chestnut tannin at 1% (CT1) and 2% w/v (CT2). Data were analyzed by using analysis of variance and followed by a post-hoc test namely Duncan's multiple range test. Results showed that the inhibitory diameters formed on the activity assay of AT in the form powder, liquid and CT with concentration of 2% against Salmonella typhimurium bacteria were 17.3, 7 and 16 mm, respectively. Inhibitory diameters of AT powder, AT liquid and CT against Eschericia coli bacteria were 17.3, 0 and 17 mm, respectively. The AT powder resulted in a higher inhibition of both pathogenic bacteria species than that of liquid form (P<0.05), whereas its inhibitory effect was similar to commercial CT. In conclusion, 2% AT can be used to inhibit the growth of Salmonella typhimurium and Eschericia coli bacteria in which its magnitude of inhibition is comparable with commercial tannin extract from chestnut.

Red color in red rice kernels is because of anthocyanins, making red rice to have high health values. Mycorrhizas are reported to affect anthocyanin contents of other crops. This research aimed to examine the effects of mycorrhiza biofertilizer on grain anthocyanin contents and yield of various promising lines of red rice under aerobic irrigation systems, by conducting field experiment in Beleke, West Lombok, Indonesia, from March to July 2018, in Split Plot design with three blocks and two treatment factors, namely red rice genotypes as main plots (G04, G10, G15, G21) and AMF bio-fertilizer as sub-plots (M0= without, M1= with biofertilizer application). Results of data analysis using ANOVA and Tukey's HSD test indicated that anthocyanin contents and almost all yield components were significantly higher on red rice supplied with AMF biofertilizer than without AMF, while those variables were mostly non-significantly different between red rice genotypes, except for 100 grain weight. Despite no interaction effects, there was a significantly positive correlation between anthocyanin contents and harvest biomass weight on red rice fertilized with AMF biofertilizers, but not on those receiving no AMF, which indicates positive effects of AMF in increasing harvest biomass and grain anthocyanins of those red rice genotypes.

Velvet beans (Mucuna pruriens) an under-utilized legume which grown predominantly in tropical area, including in Indonesia. The morphological characteristics, chemical and amino acid composition of seeds, fermented velvet beans (Benguk tempeh), and Benguk tempeh flours from the legumes Mucuna pruriens was evaluated to determine their potential practical applications. The seeds of velvet beans contains 12.73±0.10, 4.34±0.33, 25.49±0.06, 3.66±0.03, 3.90±0.06, and 53.79±0.26 (% wb) of moisture, fat, crude protein, ash, crude fiber and carbohydrate, respectively. The mineral content of velvet seeds was 76.38±8.77, 6.64±0.67, and 3.08±0.12 mg 100 g¹ of calcium, iron, and zinc, respectively. Fermentation process on velvet beans into tempeh brings nutritional changes including the breakdown of certain nutrition content and reduction of anti-nutritional compounds. The velvet beans tempeh contains 54.76±0.24, 2.40±0.16, 12.84±0.56, 1.02±0.13, 3.66±0.49, and 28.99±0.60 (% wb) moisture, fat, crude protein, ash, crude fiber and carbohydrate, respectively. The mineral content of velvet beans tempeh was 55.49±13.91, 6.56±0.39 and 2.60±0.33 mg 100 g¹ of calcium, iron, and zinc, respectively. The flours were prepared by steam blanching, oven-drying (60°C) for 7h and milling. The flours contains 13.13±0.52, 6.78±0.72, 25.29±0.41, 0.76±0.04, 4.34±0.32, and 54.06±0.47 (% wb) of moisture, fat, crude protein, ash, crude fiber and carbohydrate, respectively. The mineral content of flour was 29.43±0.00, 5.87±1.36 and 2.56±0.04 mg 100 g" ¹ of calcium, iron, and zinc, respectively. The essential amino acids profile of total flour proteins compared favourably with the FAO/WHO reference pattern except for deficiency of sulfo amino acids (methionine and sistin) with concentration of 9.72 mg g¹ crude protein. The flours have potential as flour alternatives for food product development.

ZnO is a semiconductor that has excellent activity as photocatalyst under UV light region. ZnO is precipitated by adding oxalate acid onto zinc acetate dehydrate solution with ultrasonic assisted at various times and flattened at 500 °C. The structural properties of the ZnO samples are characterized by X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET). XRD result has confirmed the ZnO structure as hexagonal phase. Rietveld refinement of XRD pattern by La Beil method is employed to analyze the lattice parameters of ZnO. It provides that ZnO as wurtzite with accurate values. Debye-scherrer equation examines the crystallite size. It is confirmed that the crystallite size of ZnO is decreased by ultrasonic assisted at precipitation. BET result shows that ultrasonic assisted could increase the surface area of ZnO, which are 45.64 m²/g of ZnO without ultrasonic assisted and 143,487 m²/g of ZnO with ultrasonic assisted along 2 hours. The photocatalyst experiment is set up to analyze the photocatalytic activity of ZnO for degradation of methylene blue under UV light irradiation. By significantly that decolorization of methylene blue occurred at pH 10 for 30 minutes irradiation. The photocatalytic activity for ZnO samples with an hour and 2 hours ultrasonic assisted are 79.54 % and 86.50 % respectively, whereas ZnO sample without ultrasonic assisted is 70.90 %, and almost all of methylene blue contaminant have done degraded successfully after 120 minutes irradiation. According to the results, the structural properties and photocatalytic activity of ZnO are increased as consequence to the presence of ultrasonic assisted on precipitation.

Tofu is one of the products processed from soybeans that contain nutrients for the body. Tofu from Lembang, Tofu from Sumedang and Tofu from Garut are three types tofu that are produced in different places. Types of microorganisms found in whey can influence the flavor of tofu. This research was conducted to find out the type of microorganisms contained in whey Tofu from Lembang, Sumedang and Garut through metagenom approach. Through this approach, the microbial species in an environment can be known, even without the need to cultivate the microorganism. Whey samples filtered by cellulose acetate membrane of 0.2 µm. Total DNA was isolated by the Klijn method, and used as a template to obtain a fragment of 16S rRNA with ± 400 bp long using touchdown PCR. Amplicons obtained then separated again by DGGE analysis. Optimization of DGGE was made with 8% gel and a denaturant range of 30%-80%. The microorganisms contained in whey Tofu from Lembang have closer homology to the Bacterium EM, microorganisms contained in Tofu from Sumedang were closer with Acinobacter sp. and Uncultured Bacterium, while microorganisms contained in Tofu from Garut were closer to Uncultured bacterium.

Aedes aegypti mosquito is one of common vectors for the pathogens of different diseases like dengue hemmorrhagic fever. The most common approach to vector-borne disease is by chemical control, mostly through the use of insecticides. As compared to synthetic pesticides, essential oils (EOs) are ecologically safe, have no mammalian toxicity or the chances of development of resistance are reasonable and highly popular with the organic growers. This research has studied the larvacidal activity of essential oil from orange (Citrus sinesis L. Obbeck) and lemongrass (Cymbopogon nardus L. Rendle). Orange and lemongrass cleaned and cut into small pieces, dried and then blended to obtain crude drug samples. Samples distilled with the Stahl distillation method for 4 hours. Furthermore, terpenoids phytochemical test and test against larvae of Aedes aegypti larvicides to obtain the LC₅₀ value. The yield of essential oil of orange (Citrus sinensis L Obbeck) obtained is 6.84%, while the essential oils of lemongrass (Cymbopogon nardus L. Rendle) was 0.96%. In the phytochemical test essential oils either of orange peel and lemongrass showed terpenoids. From the GCMS data, an essential oil from orange and lemongrass contain citronellal and limonene. Citronellal compound acts as an insecticide ingredient that works as an antifeedant and repellent. An essential oil from orange and lemongrass are toxic, with LC₅₀ values obtained from lemongrass 35.133 ppm is smaller than the orange is 790.935 ppm. The essential oil of lemongrass more toxic than the essential oil of orange. Both of essential oils can be used as a green pesticide candidates.

This study aims to determine the effect of extraction time (5,10,15 minutes) and the ratio of the aquadest solvent: ethyl acetate (1: 6.5, 1: 7, 1: 8 v/v) to the yield of pigment. The optimum condition was found in the ratio of the solvent of distilled water: ethyl acetate (1: 7 v/v) extraction time of 15 minutes with low microwave power resulted in maximum pigment yield of 0.469%. The isolate compounds were analyzed using IR spectroscopy, mass spectroscopy, and High-Performance Liquid Chromatography (HPLC) showed that the isolates were boxing pigments having a molecular weight of 394 g/Mol with wavenumbers for OH groups, C = O carboxylate groups, CH bonds, duplicate C = C, and CO ester bonds. As well as showing the retention time of standard and standard pigments at minutes to 12.849 and 12.843.

Ethyl acetate extracts from kenikir leaves contain flavanoid, alkaloids and tannins compounds. This compound can be used as a corrosion inhibitor because it contains nitrogen and oxygen atoms with a pair of free electrons so that it allows adsorbed strongly on the surface of the iron and increases the activity of corrosion inhibition. The inhibitory activity was analyzed by wheel test method or measurement of weight loss in NaCl 1 % medium with variations in concentration, temperature and electron microscopy (SEM) analysis. The inhibitory activity of kenikir leaf extract increases with increasing concentration of inhibitor. The optimum inhibition efficiency of was obtained at a concentration of 32 ppm with an inhibition efficiency of 86.84%. An increase in temperature from 25-55 ° C causes decreased inhibitory activity and achieves optimum inhibition efficiency at 25°C. Kenikir leaf extract has adsorption properties that correspond to the Langmuir adsorption isotherm with free energy of ΔGads of -14.98 KJ/mol. The results of the surface analysis by Scanning Electron Microscopy (SEM) showed that the kenikir leaf extract could inhibit corrosion rates with iron surfaces that had fewer pores than without inhibitors.

This study aims to ensure the treatment of rheumatoid arthritis cases suffered by leprosy patients. Special inspection is carried out every 2 weeks during the treatment. Treatment by giving nanogold and nanosilver volunteers every morning and night as much as 20 ml 20 ppm in drinking water. The number of volunteers 24 people with an age range of 40-70 years. The sex of male volunteers is 12 people and women are 12 people. The condition is divided into 4 categories; weight, moderate, mild and cured. In the beginning, volunteers were chosen in the weight and moderate categories. Research data were medical records and interviews. The results show a gradual recovery process towards recovery. One person with an initial condition in the weight category had not recovered for 3 months of treatment. Overall there was an improvement in conditions from weight to moderate, mild and recovered. Gender has no effect on the recovery process. The conclusions of the nanogold and nanosilver case studies succeeded in alleviating to cure rheumatoid arthritis volunteers for leprosy patients. This case study has the impact give new hopes for leprosy patients to keep their spirits alive. This is very important for the future of leprosy patients free from rheumatoid arthritis.

The tyrosinase enzyme catalyzes the first stage in two reactions in the synthesis of melanin (the hydroxylation of l-tyrosinase becomes 3,4-dihydroxyphenylalanine (l- DOPA) and oxidation from L-dopa to dopaquinone). Hyperpigmentation in human skin is a general phenomenon that is not desirable. Researchers were encouraged to identify potential new tyrosinase inhibitors for cosmetics, especially anti-hyperpigmentation. This study purposed to determine the inhibitory activity of the tyrosinase enzyme from Garcinia daedalanthera Pierre leaves. The extract was obtained by maceration successively method. The anti-tyrosinase assay used the spectrophotometric method at 490 nm. The enzyme used tyrosinase from mushrooms lyophilized powder (Sigma), and the substrate used 3,4-dihydroxy-L-phenylalanine, L-DOPA (Sigma). The tyrosinase inhibitory assay results of 100 ppm (triplicate) showed the leaves extract, including ethyl acetate extract of 33.42 ± 5.98 %, hexane extract was 50.67 ± 0.47 %, and methanol extract of 50.68 ± 1.87 %, respectively. Moreover, the stem bark has activity as follows methanol extract of 43.76 ± 1.41 % and the ethyl acetate extract of 55.71 ± 2.80 %. Percentage inhibition of the positive control (kojic acid) was 65.07 ± 0.03 % at 100 ppm.

This study aims to analyze student outcomes after learning the acid-base concept supported by PhET Simulation. The PhET simulation is used to help visualize sub-microscopic representation of the acid base solution. The method used is one group pre-test and post-test design with the subject this study consists of thirty high school students in the Bandung area. The research instrument used was a test that measured the ability to distinguish the strength of acid-base at the level of sub-microscopic representation, calculate the degree of ionization, the relationship of Ka to concentration, and analyze the pH of the solution. The result of this study it can be concluded that the PhET simulation can improve student learning outcomes to the level sub-microscopic representation.

Cyclamate is an artificial sweetener with a sweetness level of 30- 40 times greater than sucrose. This study aimed to determine the content and levels of cyclamate sweetener in unmarked beverages without labels that are prepared and sold by elementary school canteens in South Denpasar District. This research is a type of descriptive research that uses survey methods with simple random sampling techniques and experiments in the laboratory. The number of elementary schools in South Denpasar District is 72 schools. The population in this study were 145 types of unmarked beverages without labels that were prepared and sold by elementary school canteens in South Denpasar District. The number of samples sampled is 110 samples. The parameters of artificial sweeteners in this study were cyclamate tested by HPLC. Research data are presented in tables, graphs and analyzed descriptively. The results showed that of 110 samples containing 62 cyclamate (56.36%). Cyclamate levels that exceed the maximum limit requirements so that they do not meet the requirements of 44 samples (40%) and meet the requirements of 66 samples (60%), according to the maximum allowable limits refer to the Head of the Indonesian National Agency for Drug and Food Control No. 4 of 2014.

The previous studies explain that bioactive compounds from Ficus religiosa are known as an anti-inflammatory agent. In this research, we investigated the potency of bioactive compounds from Ficus religiosa by using molecular docking between eight bioactive compounds and the COX-2 receptor. The eight ligands were collected from www.pubchem.ncbi.nlm.nih.gov., while the receptor was taken from www.rcsb.org. The result of this study could be a reference for the research in the synthesis of the bioactive compound to minimize failure. The collected data was calculated through Autodock Vina embedded in MGL Tools 1.5.6, and these processes were performed using 100 runs of the Lamarckian Genetic Algorithm (LGA). The lowest energy of complexes was visualized by using Biovia Discovery Studio Visualizer. This result proved that 28-Isofucosterol-COX-2 had smaller binding energy compared to the reference ligand.

Thermochemistry is an important basic concept in studying advanced chemistry. Thermochemistry is very important to understand correctly and easily. This research aims to develop technology that can facilitate understanding of thermochemistry. This research is a research and development research (R & D). In this research, a technological development can be produced which can be used to facilitate understanding of thermochemical concepts. This research resulted in a framework of thermochemical material integrated with science (biology, physics), mathematics, engineering, ICT technology.

Neuroscience is a neural science that studies the nervous system, especially studying neurons and nerve cells with a multidisciplinary approach. The scope of the study of neuroscience includes molecular cellular, nervous system, behavioral neuroscience, and social neuroscience. Spinal stenosis occurs when the space around the spinal veins narrows, burdening the spinal cord and nerve roots. A minimally invasive approach to lumbar spine decompression is treatment for patients with spinal stenosis and spondylolisthesis This article was written to carry out a theoretical update of neuroscience with the aim of analyzing what is meant by lumbar spinal stenosis, what are the trends and minimally invasive surgical approaches for the spine and its management? Minimally invasive surgery, may provide the opportunity for a less invasive surgical intervention. It is an approach that bridges the gap between invasive surgery and more conservative treatment for lumbar spinal stenosis.

The 21^st century learning innovations must be optimized using appropriate media and learning resources. The use of technology has become an efficient alternative in the implementation of learning. This research aims to produce electronic-modules (e-modules) as teaching materials for protein metabolism using Flip PDF Professional application. The method used refers to research and development. The contents of the module are developed based upon the learning design in the Biomolecular Metabolism course according to the curriculum of the Chemistry Education undergraduate study program. In addition, the e-module is equipped with videos, images, animations, links to various main sources and formative tests on each material in accordance with the learning outcomes over the course. Product validation is carried out by material, language and media experts using standard instruments with the Likert scale. The results of expert validation of the developed e-modules show well to very good at interpretations. Based on the results from the validation it can be concluded that the electronic metabolism protein module is ready to be used as a learning material in supporting the improvement of students' critical thinking. Dissemination of the e-modules in the biochemical learning process is being carried out and will be published in the next article.

Nowadays, the development of technology emphasizes the educators to be able to utilize the technology greatly in teaching and learning processes, including the learning assessment. In fact, the implementation of the technology, such as the utilization of an online-based test, seems to develop in the process of learning assessment. Hence, this present research proposes to develop the computer-based test (CBT) application for the comprehensive test of basic chemistry in measuring the higher order thinking skill (HOTS) of the undergraduate students in the major of chemistry education department. Furthermore, to facilitate their necessaries in optimizing the computer-based test (CBT) application, it seems to indicate that the application needs a new innovation in the certain parts in terms of the design itself and the simplicity of the online test that enables to be accessed either from the mobile phones or the students' laptops. Notably, the development of the computer-based test application in the present research attempts to use the programming language PHP and MySQL in producing the database. Moreover, the author administrates five phases in promoting the application, such as developing the devices within the preliminary study, planning, creating the product design, testing the limited product, and revising the limited product testing. As the result, the findings of the research are expected to become the primary component in developing the online assessment. In other words, it enables to measure the learners' competencies in comprehending the learning materials of basic chemistry and the higher order thinking skill for the undergraduate students of chemistry education department.

The addition of white turmeric extract as an antibacterial to edible starch-based films aims to improve the resilience of food packaged against bacteria so that the quality is more maintained. The method carried out in this study consists of three things. The first step was the preparation and characterization of orange sweet-potato starch (including starch and moisture content). The second stage is the preparation and characterization of white Tumeric extract by phytochemical tests. The third stage is the preparation and characterization of edible films (including water resistance tests, mechanical properties tests. The result of starch characterization obtained the starch content of 43.16% with a moisture content of 13.95%. The result of the characterization of edible films by adding the best white turmeric extract was 7% with the tensile strength, and combined-successful elongation values were 40.9209 ± 2.5290 MPa and 18.03%. The results of antibacterial testing on E.Coli ATCC 11229 did not produce an inhibitory zone and on S. aureus ATCC 6538 was a clear zone but could not construct that indicates the presence of very weak antibacterial potential in edible films by adding white turmeric extract.

Increased thinking at a high level is needed so that students are able to solve the problems faced in their lives based on Islamic values. This study aims to analyze the improvement of higher order thinking skills based on Islamic values on the application of green chemistry-based synthetic polymer e-modules. The research design used was a one-group pretest and posttest with research subjects that were 26 semester VI students of the Chemistry Education Study Program. The results of this study indicate that the application of synthetic chemistry based on green chemistry e-module can improve the ability of high-level thinking based on Islamic values based on the average gain of n-gain 0.647 which is included in the medium category. Learning using this e-module can improve learning outcomes by making learning situations more active so as to better understand the concept of synthetic polymers based on green chemistry. Thus, the application of synthetic chemistry based on green chemistry e-module can improve the ability to think at a high level.

The D-Loop region of human mitochondrial DNA (mtDNA) has a higher level of polymorphism compared to nuclear DNA. Therefore, the mtDNA D-Loop area can determine a particular individual or ethnic identity. This study aims to determine the variation of the D-Loop region nucleotide sequence, namely the Hipervariable I (HV1) region in normal tribal individuals in Kampung Naga and Kampung Kuta. The sample used is the hair root. In determining the variation of nucleotides has been carried out a series of stages of research, namely the isolation of mitochondrial DNA from hair root samples using buffer lysis, mtDNA sample amplification using PCR techniques with M1 primers and HV2R primers, detection of D-Loop region mtDNA fragments by agarose gel electrophoresis, and sequencing of PCR products by the Sanger Dideoxy method and nucleotide sequence analysis of the sequencing results. The results of DNA amplification by PCR showed a band in the area of 1.0 kb. Homology analysis was carried out by comparing the nucleotide sequences of samples with the Cambridge nucleotide sequence, which shows that there are 10 variations. The new variation (morph) is determined by comparing the results of the variations of the two samples with variations from Homo Sapiens Indonesia including Baduy, Sundanese, Javanese (Sangiran), and Madura. Homology results showed 4 new variations, namely c(16184)A, t(16209)C, a(16272)G, t(16519)C. Sapiens Kuta village and Sundanese (general) have a close genetic relationship. The ancestors of the two Homo Sapiens were closely related to Homo Sapiens Naga, Homo Sapiens Naga are closely related to the Homo Sapiens of the Baduy. The ancestors of Homo sapiens, Kuta, Sundanese, Naga and Baduy, are closely related to Homo sapiens Sangiran (Java). Homo Sapiens Madura is most likely the oldest Homo sapiens seen from phylogenetic trees. The results of this study are expected to be able to add Indonesia's normal human database.

Adding value of slaugtherhouses products and wastes today become greater attention, especially bone wastes for renewable biomaterials, in supporting sustainable green industries. However, the high potency of developing the renewable bioinorganic materials from bone wastes needs a comprehensive need assessment. The need assessment was conducted through three steps: literature search metaanalisis study for defining the needs, collecting and analysis data, and making decision of the needs. Results of the study showed that (1) there were prospective and sustainable raw materials from slaughterhouses in Indonesia, especially bones, for developing phosphate based bioinorganic materials; (2) there were some needs of developing bioinorganic nanoparticles materials in M-Si-P-O, M-Al-P-O, and M-Al-Si-P-O systems (with M = main and/or transition metals) for artificial bones and teeth purposes; and (3) there were some needs of developing thermo-hydrochromic bioinorganic materials sensoric temperature and humidity for supporting artificial insemination as well as medicinal purposes. The last result of the study was supported by current finding on natural inorganic thermo-hydrochromic pigment.

The right time for cooking nila nyat-nyat is very influential on subjective and objective value of nila nyat-nyat. The goal of this study was to determine the best time in cooking tilapia in order to get the best quality of nila nyat-nyat. The research was conducted at the Laboratory of the Faculty of Agriculture, Warmadewa University and the Faculty of Food Technology, Udayana University. This research used experimental method with completely randomized design of single factors with 6 different treatments and 4 replications. Quality assessment includes subjective tests through organoleptic analysis such as appearance, texture, odor, and taste, and also objective tests or nutritional analysis, such as water, fat, protein, and ash content. Statistical analysis with anova showed that the difference in cooking time gave significant influence in the organoleptic quality and nutritional value of tilapia (p value < 0.01). From this research, we conclude the best time for cooking tilapia was 30 minutes.

Red dragon fruit (Hylocereus costaricensis) contains anthocyanin which is a polyphenol compound that is rich in pigments, determining the formation of red, purple and blue colors of various fruits and vegetables. Wine fermentation is the process of breaking down sugar into alcohol and CO2 gas due to enzymes produced by yeast cells. Factors that influence the fermentation process are the type of yeast, sugar content, nutrition, temperature, aeration, and pH. The fermentation time in making fruit wine is very important to know to produce wine with good characteristics. This study aims to determine the effect of sugar levels and the best fermentation time on the characteristics of red dragon fruit wine (Hylocereus costaricensis). This research was conducted at the Food Processing Laboratory of the Faculty of Agriculture, University of Warmadewa. Research with a Completely Randomized Design (CRD) consisting of 2 (two) factors and two replications, the first factor is sugar content, which consists of four levels: 10%, 15%, 20%, 25%. The second factor is the fermentation time, which consists of three levels: 10 days, 15 days, 20 days. Variables observed in dragon fruit wine include objective observations: levels of methanol and levels of ethanol. From the results of the study obtained 10.42% ethanol content, and the wine produced does not contain methanol.

Typhoid fever caused by Salmonella typhi is an endemic disease in Asia, including Indonesia. Based on data from the World Health Organization (WHO), there are 81% per 100,000 people in Indonesia infected with typhoid. Based on this, development of typhoid detection kit that is simple, fast, specific and sensitive is still needed. One of the developments of detection kits currently available is the antigen and antibody interaction approach. This study aims to obtain comprehensive information about purification of recombinant Fim-C-S. typhi proteins as antigens for raw materials for manufacturing typhoid detection kits. This study uses the IMAC method with Ni²⁺ metal, which has advantages in high selectivity and purity. The results of this study report that purification of recombinant Fim-C-S. typhi protein inclusion bodies with variations in the binding and washing process at 3, 5, and 7 times gave percent yields correspondingly of 37.84, 39.44, and 38.21% pure protein. Previous studies have also reported variations in binding and washing at 2, 4, and 6 times and gave percent yields respectively were 35.37, 39.11, and 40.49%. Based on the data, we concluded that the variation of 6 times is the best repetition variation to get the largest percent yield so that it can be used as a reference in large-scale purification.

Salmonella typhi is gram-negative bacteria that caused typhoid fever in humans; prevention of the disease is currently through vaccination. The development of disease detection tools is also being carried out so that the detection process is faster and more accurate. In line with the development of typhoid detection devices, prior studies have managed to find factors that influence the production of Fim-C S. typhi protein on a small scale as raw material for typhoid detection kits. The purpose of this research is to apply the results of previous studies in the production of recombinant Fim-C-S. typhi proteins with volume variations of 50mL-300mL, as a foundation for large-scale production. The results of protein production were characterized by Sodium Dodecyl Sulfate Polyacrilamide Gel Electrophoresis (SDS-PAGE) and protein concentration measurements using the Bicinchoninic Acid (BCA) Assay at a wavelength of 562 nm. The results showed an amount of that protein increase along with gradually production volumes, mainly the protein in the form of inclusion bodies. According to the results obtained can be concluded production of the recombinant protein Fim-C-S. typhi at 50-300 mL volume variation on a laboratory scale has been successfully performed with consistent results, which is expected to be basic in production at pilot scale and large scale.

Bali is an island that is famous for its culture, including traditional medicine. In traditional medicine, the Balinese use various kinds of medicinal plants, one of which is Turmeric. The purpose of this study was to determine the ways and objectives of the use of turmeric by Balinese, as well as the phytochemical content and antioxidant capacity of turmeric extract which is traditionally processed in Bali. The method and purpose of utilizing turmeric were obtained through observation and interviews with 900 Balinese respondents. Quantitative phytochemical tests include starch, protein, flavonoid, tannin, phenol and vitamin C levels and qualitatively for the presence of triterpenes, steroids, alkaloids, and saponins. Antioxidant capacity was measured using the DPPH method. Through this research, we found there were only 36.8% of respondents had ever used turmeric as a traditional medicine. Utilization of turmeric was mostly in the form of loloh or traditional drinks. Phytochemical test results showed turmeric extract had 67.38% starch, 3.42% protein, 2709.39 mg/100 gr flavonoids, tannins 291.64 mg/100gr, phenol 1584.04 mg/100 gr, and vitamin C 0.06 mg/100gr. Qualitatively, turmeric extract contained triterpenes, alkaloids, and saponins, but did not contain steroids. The antioxidant capacity of turmeric extract was 70.9 mg/L GAEAC. Turmeric extract is a traditional medicine made from nature that is most commonly used by Balinese and very potential to be developed as an antibacterial, antioxidant, anti-inflammatory, or other benefits that still need further investigation.

This study aims to develop innovative learning media that is mobile learning through scientific approaches on Electrolyte and Redox and to find out the feasibility of media produced. This research was conducted at SMAN 39 Jakarta and SMAN 98 Jakarta from January to May 2019. The research method used is Research and Development (Borg and Gall) by modifying five stages, namely: needs analysis, product development, validation, and product test. The resulting mobile learning media is called "Electrolyte and Redox.apk" that is compatible with Android devices and provides a summary, videos, simulations, quizzes, and educational games. Feasibility test by topic and language expert acquired 83%-100% with 0.808 of reliability. Feasibility tests by media experts acquired 91%-100% with 0.812 of reliability. Media trials by chemistry teachers acquired 88% -100% with "very good" criteria. Media trials by small scale students received 88%, and a large scale gained 92% with "very good" standards. Based on the results, it can be concluded that mobile learning media through the scientific approach in Electrolyte and Redox topic proper to use as a learning media and suitable for students and teachers needed.

This study aims to develop mobile learning on stoichiometry based on the scientific approach. Mobile Learning was tested in two different high schools. Research and Development method by Borg and Gall used by modifying stages of need analysis, development, validation, and product test. The result of need analysis indicated necessary media, which provide a summary, exercise, practical video, animation video, and educational games as learning based on scientific support in stoichiometry. 74% of respondents liked mobile learning. At the development phase, designed mobile learning media and storyboard along with software chosen to make mobile learning. The feasibility test of the media produced 88% with a reliability of 0.77. Feasibility test for topic and language feasibility test produced 88% with a reliability of 0.9. Chemistry teacher's test acquired 92% as the best criteria. Small-scale student tests acquired 81%, and big-scale student tests acquired 83% considered as the best criteria. According to this, the study concluded that mobile learning media based on scientific in stoichiometry topic is proper to use and suitable for students and teachers needed.

This research aims to determine the growth response and yield of several Black Soybean varieties in several variations of spacing. The experiment is a factorial experiment using a randomized block design (RBD) consisting of two treatment factors, the first factor is the variety consisting of 3 levels: V1 = Detam 1, V2 = Detam 3 Prida, V3 = Detam 4 Prida. The second factor is spacing which consists of 3 levels: J1 = 20 cm x 20 cm, J2 = 20 cm x 30 cm, J3 = 20 cm x 40 cm. The interaction of varieties with plant spacing has a very significant effect on crop dry weight and seed oven per planting hole. The significant effect the yield seeds of dried and oven per hectare. The weight of oven-dry seeds per planting hole and the highest yield of oven-dried seeds per hectare was obtained in the interaction of Detam 1 varieties with the spacing of 20 cm x 40 cm with was 33.79 g and 2.53 tons per hectare which increased 138.79% and 42.93% compared with the interaction of Detam 4 Prida varieties with a spacing of 20 cm x 20 cm with was 14.15 g and 1.77 tons per hectare.

The study aims to determine the effects of giving several types of manures on various chili pepper varieties. The experiment is a factorial experiment using a randomized block design (RBD) consisting of two treatment factors, namely type of manure (R) of 3 levels: R1 = Chicken Manure, R2 = Cow Manure, R3 = Rabbit Manure and type of varieties (V) of 4 levels: V1 = Genie varieties, V2 = Dewata varieties, V3 = Sigantung varieties, V4 = Gendut varieties. The interaction of varieties and type of manure as a very significant effect on the number of leaves and root fresh weight and significant effect on fresh weight and oven-dry leaves. The highest fresh weight and oven-dry weight was obtained in the interaction of Genie varieties with cow manure, namely 10.06 g and 1.68 g with an increase of 285.44% and 342.10% compared with the interaction of Sigantung varieties with cow manure, namely 2.61g and 0.38 g. The highest fresh root weight was obtained in the interaction of Genie varieties with cow manure, which was 3.09 g or increased 286.25% compared to interaction between Dewata varieties and cow manure, which was 0.80 g. Genie varieties with cow manure types provide better chili seedling growth compared to Dewata varieties and Sigantung varieties.

Japanese quail (Coturnix-coturnix japonica) has great potential to be developed as an alternative source of cheap animal protein. Generally, quail breeders use commercial rations. The problem is that commercial rations are expensive. From an economic perspective, the cost of the ration is very high, reaching 70% of the total cost of production. To reduce the cost of ration and to maintain the nutritional quality, it is tried to substitute commercial rations using feed ingredients that have good nutritional content and the price is cheap by using waste bean sprouts. The purpose of this study was to determine the chemical quality of commercial quail laying rations substituted with fermented waste bean sprouts. The study used a completely randomized design (CRD). The treatment consisted of substituting 0%, 5%, 10% and 15% waste bean sprouts in the commercial quail laying ration. From the research results obtained that the substitution of fermented waste bean sprouts in commercial quail laying rations has a very significant effect (P<0.01) on dry matter, water content, ash content and organic matter. Substitution of waste bean sprouts in quail laying rations up to the level of 10% produces the lowest ash content and water content and meets the SNI standard, as well as the highest organic matter content of the ration

The purpose of this study was to determine the effect of fermented cassava peel flour on carcass weights and parts of broiler carcasses. This study used 45 CP-707 broiler strains. The design used was a randomized design complete with 3 replications. This study uses fermented cassava peels mixed in ration with 5 level administration, namely: without fermented cassava skin flour (P0), fermented cassava skin flour 3% (P1), fermented cassava skin flour 6% (P2), fermented cassava skin flour 9 % (P3), and 12% fermented cassava peel flour (P4). The application of fermented cassava peel at 9% level in the 6-week broiler ration did not significantly affect all observed variables, but application at 6% level tended to increase carcass weight, breast weight, thigh weight, and wing weight. The fermentation of cassava peel flour at 12% in the ration had a significant effect in reducing carcass weights and weight of broilers at 6 weeks. The results showed that fermentation of cassava peel flour in rations up to 6% tended to increase carcass weight, chest weight, thigh weight, and swing weight, whereas at 12% had a significant effect in reducing carcass weight and weight of broilers at 6 weeks.

Contamination by pathogenic mold in postharvest cocoa beans becomes a significant concern by most Indonesian farmers. Pathogenic mold can cause damage to cocoa beans by such as rotting diseases in fruit. One alternative that can be used to control pathogenic mold is using biological agents such as yeasts. Some group of yeasts can produce cellulase enzyme that can degrade cellulose, and it can possibly break the cell wall with of mold which composed of semi-crystalline chitin, p-need, and cellulose. This study aims to determine the yeast originated from fermented cocoa beans which can produce cellulase enzymes and their potential ability as a biocontrol for pathogenic molds in chocolate fruit. This study includes yeast isolation from fermented beans, screening of yeast isolates that produce cellulase enzymes, and in-vitro antagonistic testing against pathogenic molds on chocolate fruit. The results showed that there were 21 yeast isolates from fermented cocoa beans, and among all, there were five isolates which can produce cellulase enzymes, namely isolate C4.-3.3, C4.-3.13, C4.-4.9, C4.-4.10, and C4.-5.9. Yeast isolate C4.-4.10 can produce cellulase enzymes with an index of 0.32 U/mL. This research showed that the 5 yeast isolates have the low category of cellulase enzyme, and further study is needed to be done to confirm their ability to act as a biocontrol agent.

Mold is one of the microorganisms that can cause damage in chocolate fruit by producing phytopathogenic toxins. Until now, pesticides have been widely used for controlling postharvest loss in fruit. Yeasts can produce secondary metabolites, which can inhibit the growth of pathogenic mold. In this study, we isolate, identify, and apply yeasts isolated from fermented cocoa beans to control the growth of pathogenic mold in chocolate fruit collected from Sentul, Indonesia. This research includes yeast isolation using the dilution method with YMA medium, mold isolation using direct planting method on PDA medium, screening ability to produce cellulase using diffusion method on CMC medium, and in-vitro antagonist testing using dual culture method on PDA medium. The results showed that 128 yeast isolates and 37 mold isolates were obtained in this study. The results of screening representative cellulase capability of 77 yeast obtained 6 positive yeast isolates produced cellulase with the highest cellulolytic index of 0.23-0.30. The 6-yeast antagonism test with the highest cellulolytic index showed that C3.3.1 isolate had the best ability to inhibit pathogenic molds with 37.36% inhibitory power.

Cooking oil consumption in Indonesia is very high and tends to rise every year, reaching 500,000 tons/year. Waste of used cooking oil pollute water and reduces the biota. Therefore, the conversion of used cooking oil will help to reduce environmental damage. One of the conversions done is making the bulk cooking oil into soap. This study aims to determine the effect of NaOH concentration on the quality of soap made from purified used cooking oil. Activated charcoal from sugarcane bagasse was used in the conversion of soap to diminish odor and brown color. This study was designed using an experimental method with descriptive analysis. The treatment in this study was the difference in NaOH concentrations of 10%, 30%, and 50% with each concentration repeated three times. The results obtained showed that the most optimal NaOH concentration is 50% since it has a dense soap consistency. In contrast, the 30% NaOH concentration has a semi-solid soap consistency. At 10% NaOH concentration the consistency of soap is still liquid. It can be concluded that the concentration of NaOH affects the quality of the soap.

This study aims to determine the effect of rabbit manure, biochar from chicken manure, and its interactions on the growth and yield of pakchoy plants. This study uses a randomized block design (RBD) with factorial patterns (2 factors). The first factor is the dose of rabbit manure which consists of 4 levels (0, 10, 20, and 30 tons ha⁻¹). The second factor is the biochar dose of chicken manure consisting of 4 levels (0, 5, 10, and 15 tons ha⁻¹). The results showed that the treatment of biochar dose of chicken manure and the treatment of interactions between the dose of rabbit manure and the biochar dose of chicken manure had no significant effect on all observed variables. The treatment of rabbit droppings did not significantly affect all observed variables, except that the fresh weight of the roots showed a real effect. Fresh weight of economic results in the application of rabbit manure 30 tons ha⁻¹, gives a higher yield or an increase of 17.08% when compared to without rabbit manure. While the fresh weight of economic results on the application of biochar from chicken manure 30 tons ha⁻¹ gave higher yields or increased by 23.86% compared to without biochar.

The study aimed is to develop students' chemical literacy through dilemmas stories and STEAM project in chemistry learning in colloid topic. The dilemmas stories of environmental pollution were explored to engage students in contextual problems. The STEAM project of smoke absorbance was used as the problem solutions in dilemmas stories. The learning approach consists of several steps such as value reflection, problem solving, project development, project monitoring and evaluation, and transformation. The research employed qualitative approach with data collection of students' interviews, reflective journals, observations, and chemical literacy tests. Chemical literacy consists of several dimension such as scientific ideas, chemical characteristics, chemistry in context, high-level learning skills, and affective aspects. The results showed that the average chemical literacy ability of students were 85,29% in the good category. The teacher faced the challenges in developing dilemmas stories to be relevant to chemistry concepts and curricula. Students need to shift their paradigms within active learning approach. The results of this study can be concluded that the integration of dilemmas stories in the STEAM project provides opportunity to develop students' chemical literacy.

Laboratory activities are inseparable from learning chemistry. Consequently, chemistry students should master several skills in the laboratory, which they might not have it in secondary school. However, there are many potential hazards to be considered in activities in chemical laboratories. The lack of knowledge and experience of first-year chemistry students causes the possibility of accidents in the chemical laboratory higher. Therefore, in this study, chemistry laboratory safety videos were developed and assessed by experts, while questioners and interviews were used to collect the data. The assessment result is that the videos are feasible and ready to use after the input from experts and users are implemented in the developed videos.

Neem (Mimba) is one of the types of plants that are the potential to be developed commercially as plantations and community forests. The purpose of this research is to find outperformance of neem seedlings on compost and urea fertilizer dose treatment. This experiment consisted of two factors arranged factorially using a Randomized Block Design. The first factor is the dose of compost with three levels, namely 200 g, 400 g, and 600 g per pot. While the second factor is the dose of urea fertilizer which consists of two levels, namely 2.5 g and 5 g per pot. The results showed that there was an interaction between compost dose and urea dose and had a very significant effect on root length per seed and significantly affected oven-dry weight per seedlings of neem. The highest root length of the neem seedlings of this experiment indicates that the doses of compost at a 200 g per pot and urea fertilizer of 2.5 g per pot was 28.00 cm and oven-dry weight of the roots of neem plant seeds was 2.81 g.

Increased livestock productivity is largely determined by the availability of sufficient forage. Good forage is determined by digestibility, which is related to physical quality. This study aims to determine the physical quality of several types of grass planted with Arachis legumes and the provision of organic fertilizer. This study used a Randomized Block Design with a factorial pattern consisting of 3 types of grass planted with Arachis legumes (factor A) and fertilizing 2 types of solid and liquid organic fertilizer (factor B) with 3 replications. The treatment combinations are: R₁C (Paspalum notatum with Arachis pintoi+Compost), R₁B (Paspalum notatum with Arachis pintoi+Biourine), R₂C (Paspalum conyugatum with Arachis pintoi + Compost), R₂B (Paspalum conyugatum with Arachis pintoi +Biourine), R₃C (Axonopus compresus with Arachis pintoi+Compost), R₃B (Axonopus compresus with Arachis pintoi+Biourine). The results showed no significant difference (P>0.05) both in the mixture of some grass plants with Arachis pintoi and the provision of organic fertilizer on the physical quality of forage. In planting a mixture of Axonopus comprsus grass with Arachis pintoi showed average dry matter (DM), water regain capacity (WRC), and water solubility (WS). Whereas compost gets higher average values than biourine for dry matter, WRC and WS. The combination of mixed planting and fertilizing, compost showed the highest average, especially water solubility (WS). From this research it can be concluded planting a mixture of grass and legumes fed with compost on average is better for the physical quality of the grass, but not significantly different (P>0.05) from all treatments.

Coffee husk tea, well-known as cascara tea, is a by-product of coffee processing. It contains phenol compound that has antioxidant activity. Total phenol compound is extracted by brewing process. It is commonly called polyphenol compounds. Polyphenols extraction process is deeply connected to brewing method, especially the time. The purpose of this study was to determine the effect of brewing time on pH, polyphenols content, and antioxidants activity of cascara tea. This study was carried out in Completely Randomized Design with variations of brewing time in 5 levels from 5 minutes, 7 minutes, 10 minutes, 12 minutes, and 15 minutes. The results showed that the variation of brewing time significantly affected the levels of pH values, polyphenols content, and antioxidant activity of cascara tea. The brewing time of cascara tea for 10 minutes has the highest level of polyphenols content and antioxidant activity. Meanwhile pH values was decreased during brewing process.

The objective of this study was to develop an electroanalytical technique for the analysis of antioxidant compounds. Five different samples from five monofloral honeys were used. The electroanalysis experiments were conducted using two different techniques, namely cyclic voltammetry (CV) performed with a scan rate of 50 mV/s and differential pulse voltammetry (DPV) with a pulse amplitude of 50 mV and a scan rate of 10 mV/s. All samples were also analyzed by spectroscopy techniquesusing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) microplate method. The electrochemical index determined using the DPV technique agreed with the spectrometric DPPH measurements. This resultdemonstrates that the electroanalysis method could potentially be utilized for antioxidant analysis of honey samples.

The Olive Tree (Olea europaea) is a plant originating in the Middle East. Olea Europaea plant is contained several secondary metabolites such as olive oil, phenolic compounds, flavonoids, triterpen, biphenol. The aims of this research are to isolate and identify a flavonoid compound that extracted in the ethyl acetate of olive leaves. Isolation was carried out by meseration, liquid vacuum chromatography, column chromatography and thin layer chromatography. Isolation results obtained 10 mg isolates were identified using proton nuclear magnetic spectroscopy (¹H-NMR) and carbon (¹³C-NMR). According to spectra analysis, describe that isolate is chrysoeriol.

A molecular docking was performed in this research by using ArgusLab version 4.0.1. It was used to explore the capability of Calixarene analogs for aromatic amine extraction. There are 6 Calixarene analogs used in this research, i.e. Calixpyrrole, Calixpyridine, Thiacalixarene, Heterocalixaromatic, Calixcarbazole and Calixnaphtalene; and the aromatic amine used in this research are Aniline, 4-Chloroaniline, Toluene-2,4-diamine, 2-Naphtylamine, 4,4'-Metylenbis(2-chloroaniline), 4,4'-Metylendianiline, N-Nitrosodiphenylamine, Benzidine, 2-Aminobiphenyl, 2-Amino-1-methyl-6-phenylimidazo [4,5-b] Pyridine, 3-Trifluoromethylaniline, p-Phenylendiamine, o-Toluidin, 4-Chloro-o-toluidin. In this molecular docking simulation, the guest molecule of aromatic amine compounds were treated as ligand and host molecule of calixarene and its analogs were treated as binding site. This molecular docking simulation used AScore scoring function, binding sitebox size for host molecule with grid size of 0.4 Å, GA docking engine with flexible ligand, 50 population sizes, 1000 max generations, 5 elitisms, 0.2 mutation rate, and 0.8 crossover rate. Calixcarbazole and Calixnaphthelene is the best host molecule for aromatic amines extraction because the inclusion complexes formed between them have negative value of binding energy.

Indonesia is the largest coconut producing country in the world. They are many products from coconut that have high economic value, one of them is VCO. No research has been found in making VCO by kefir fermentation, so the purpose of this research is to describe the comparison of characteristics VCO produced on kefir addition based on organoleptic, water content, and free fatty acid tests. This research was carried out using two replications of the three old coconuts obtained 1.26 L thick coconut milk, then divided into three samples, fermented 48 hours with different treatments (0% kefir for control; 3.5%; 6% kefir). The results of this study obtained the best VCO characteristics in the composition of 3.5% kefir addition, colorless, normal taste, and aroma of coconut aroma, with water content of 0.0028% and a free fatty acid content of 0.23%. The VCO produced are in accordance with SNI VCO 7381: 2008. Further research needs to be conducted to produce an optimal VCO randement with a range of 1-3.5% kefir addition.

Litsea petiolata Hk. f was included Lauraceae family, and the previous study had been isolated 5 compounds from the Litsea petiolata Hk. f stem bark dichloromethane extract namely harman or aribine, norharman, reticuline, isoboldine, and thalifoline. Antioxidants can prevent tissue damage by free radical. Free radical production continuously in all cells as cellular function usually, but excess production can cause many diseases. The research aimed to assay the activity of antioxidant from the extract and fractions of the Litsea petiolata Hk. f stem bark with DPPH assay and FRAP assay. The extract was obtained by soxhletation used dichloromethane as solvent. The fractions fractionated with column chromatography. The antioxidant test used DPPH assay and FRAP assay. The IC50 values for the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test of the dichloromethane extract was 27.36 µg/mL, the fraction A was 113.74 µg/mL, fraction B was 60.17 µg/mL, and the control positive (quercetin) was 3.96 µg/ml. The EC50 values for ferric ion reducing antioxidant potential (FRAP) test of the dichloromethane extract was obtained 13.47 µg/mL, the fraction A was 76.49 µg/mL, fraction B was 55.73 µg/mL, and the control positive (quercetin) was 14.01 µg/ml. The extract had higher antioxidant activity than the fractions, and by FRAP test the extract showed better antioxidant activity than the positive control (quercetin).

PM3 Semiempiric Quantum calculation has been done in this research by using Gaussian 2009 Rev. D 01 software package to explore the capability of Calixarene and its analogs for aromatic amine extraction. The Calixarene analogs used in this research are Calixpyrrole, Calixpyridine, Thiacalixarene, Heterocalixaromatic, Calixcarbazole and Calixnaphtalene; and the aromatic amine used in this research are Aniline, 4-Chloroaniline, Toluene-2,4-diamine, 2-Naphty lamině, 4,4'-Mety lenbis(2-chloroaniline), 4,4'-Metylendianiline, N-Nitrosodiphenylamine, Benzidine, 2-Aminobiphenyl, 2-Amino-1-methyl-6-phenylimidazo[4,5-b] Pyridine, 3-Trifluoromethylaniline, p-Phenylendiamine, o-Toluidin, 4-Chloro-o-toluidin. The most suitable host molecule of calixarene analogs for extraction of aromatic amine compounds are Calixnaphthalene and Calixpyridine because all of aromatic amine compounds form inclusion complex with them spontaneously shown by negative value of binding energy.

Fish sauce can be made from fermented fish. In fermentation plays a role Lactic Acid Bacteria (LAB). The role of lactic acid bacteria has a preservative effect because it can produce compounds that can inhibit the growth of various microbes. Besides lactic acid bacteria produce bacteriocin which also function as antimicrobials. The purpose of this study was to be able to isolate bacteriocin from fish sauce with SDS-PAGE electrophoresis. The study was conducted at the Laboratory of Agricultural Biotechnology Udayana University, Denpasar with a Descriptive Method. The research was carried out in sequence, namely, isolating lactic acid bacteria from fish sauce, Growing Lactic Acid Bacteria on Poor Nutrient Media so that its growth is depressed, because with life stressed Lactic Acid Bacteria can remove Bacteriocin as an Antimicrobial agent. With SDS-Page you will see separate proteins according to their weight, which are specific bands. The protein band which ranges from 17.0 kDa - 17.5 kDa is bacteriocin

Anthocyanin from Dioscorea alata L has been successfully extracted using a methanol solvent and has been tested for its sensitivity to pH changes using a UV-Vis spectrophotometer in citrate and phosphate buffer solutions. The extracted anthocyanin showed positive flavonoid and phenol tests. The total yield of crude extract was 1.63% that is related to 3.34 x10⁻⁷ M or 16.72 mg/kg dried sample. The maximum absorption against citrate buffer is at a wavelength of 600 nm with a linear range toward pH 4 to 8, sensitivity = 0.121 and R² = 0.98. Furthermore, the maximum absorption for phosphate buffer occurs at a wavelength of 590 nm that has a response linear in the range of pH 6 to 8 and sensitivity = 0.296 (R² = 0.97) The optimum concentration of citrate buffer is 0.1M with a linear pH of 4-8 and sensitivity = 0.121 (R² = 0.98). The optimum buffer concentration for both citrate and phosphate buffer solutions were reached at 0.1M and 0.075 M, respectively. The extracted anthocyanin showed stable response properties against citrate and phosphate buffer for 140 minutes during the test period. This anthocyanin is potential to be used as an active substance to developed optical pH sensors and biosensors based on the determination of pH change.

Batik in Jambi is located along the Batanghari river, making it easier for craftsmen to throw waste into the river. Batik waste containing heavy metals used is organic and inorganic dyes that are difficult to degrade naturally in the environment. The use of this dye by the batik craftsman industry has a negative impact on aquatic life, this study aims to detect the content of heavy metals and the views of Muslim intellectual. Detection of heavy metals using ICP (Inductively Couple Plasma) and proven to contain inorganic compounds that contain heavy metals Cd, Co, Cr, Cu, Fe: 1,335; 1,287; 1,325; 0.877; 1,022 mg/L. As a Muslim intellectual this is a challenge that must be resolved because it is his duty and together look after and find solutions to what has happened, all the inhabitants of the earth are responsible for the care of the earth. Earth is a place where we can do good and worship in a clean, friendly place with the earth, then friendly with its contents, we associate the environment with science and religion (greendeen).

Vitex trifolia (Legundi plants) is a plant that is widely used as an ingredient of traditional medicine in Lombok Island for a variety of microbial infections. In this study, a qualitative test of V. trifolia methanol extract was shown to contain secondary metabolites, such as steroids, saponins, alkaloids, flavonoids, terpenoids, and tannins. The inhibitory test of methanol extract of roots, stems and leaves of V. trifolia against pathogenic bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Klebsiella pneumoniae) has been carried out. The experimental design used was a Completely Randomized Design. The treatment factor was the concentration of methanol extract with 4 levels (C1 = 7.5%, C2 = 15%, C3 = 30%, C4 = 60%). The extraction method used was methanol maceration, and the well diffusion method was used in antibacterial activity assay. Data were analyzed by using Anova followed by DMRT test. Anova analysis results showed that differences in the concentration of methanol extract of leaf have a significant effect in inhibiting the growth of all tested bacteria. The DMRT showed that the best treatment was with 60% methanol extract. In this study, S. aureus was the most sensitive bacterium to V. trifolia methanol extract, compared to other test bacteria. It can be concluded that the methanol extract of V. trifolia is an effective antibacterial source, especially against S. aureus.

Wet noodles are generally made from flour and water or other additives. They are formed in a typical noodle and have been through the process of boiling or steaming. Wheat flour is derived from wheat which cannot grow well in Indonesia. One of the drawbacks of wheat flour that has less natural color. Sweet potato is one source of carbohydrates with cream, yellow, orange and purple flesh. The natural color in the sweet potato has a function as a good antioxidant to maintain body health. The disadvantage of sweet potato does not contain gluten, which functions as a form of elasticity in the noodles. Thus in this research, sweet potato puree substitution will be carried out in the processing of wet noodles. The method used is an experiment with a complete random design. The results showed that the maximum amount of sweet potato puree added was highly dependent on the amount of water content of the sweet potato puree. Orange sweet potato puree has a higher water content than yellow, cream and purple flesh sweet potatoes. Comparison of the amount of sweet potato puree with 1: 1 flour, except for the orange flesh sweet potato 0.8: 1. The time of kneading and the time of the attainment of a smooth noodle dough is highly depend on the water content of sweet potato puree. The higher water content, it leads to form a smooth mixture. The addition of sweet potato puree can extend the shelf life of wet noodles in the refrigerator temperature.

Molecular docking simulation has been done in this research by using Hex version 8.0 software package, respectively, to explore the interaction between insulin and silica nanoparticle. Silica nanoparticle acts as receptor and insulin acts as ligand in this research. It was found that insulin form more stable interaction when it is in the pore of silica nanochannel than on the surface of silica nanosheet. Insulin prefer to interact with silica atoms than oxygen atoms in the pore of silica nanochannel

Garcinia xanthochymus is a plant found in Indonesia and rich in quercetin. Ethanol extract of bark can reduce LDL levels. Xanthon from the G. xanthochymus has antidiabetic activity. This study aims to determine the anti-elastase activity of n-hexane extract and methanol extract of G. xanthochymus pericarp. Samples were macerated for one time 24 hours using n-hexane and methanol, respectively. The elastase enzyme inhibition test used spectrophotometry methods by reacting extracts with the porcine pancreatic elastase enzyme and using the substrate N-Succ-(Ala)-3-p-nitroanilide (SANA). Absorbance was measured at a wavelength of 405 nm with a microplate reader. The results showed that the concentration of 100 ppm extract of n-hexane extract of pericarp had enzyme inhibiting activity 65.17 ± 6.44%, methanol extract of pericarp 29.81 ± 10.67%. Meanwhile, the inhibitory activity of quercetin elastase enzyme as a positive control was 62.75 + 1.89%. This research concludes that the n-hexane extract of the pericarp of G. xanthochymus has activity as an inhibitor of the enzyme elastase is very high and can potentially be used as a material for making cosmetics.

This study aims to improve students' understanding at the Vocational High School of Chemical Analysts on spectrophotometric concepts through experiments using smart phone technology. For this research, The ColorMeter application with matching red green blue (RGB) colors is used as a simple spectrophotometry. The use of smartphone as a simple spectrophotometry in practicum can maximize spectrophotometric learning activities in the classroom since these are often constrained by the limited access to the instrument. Through finding an alternative method, learning objectives can be properly achieved and practical application is easily attained. This RGB – ColorMeter application can be used to read the transmittance of a colored solution by utilizing the complementary colors of the solution being tested. Transmittance data obtained is used to find the absorbance of the solution, so that it can determine the concentration of a substance in the solution. The results showed that the application of RGB - ColorMeter can show a linear graph between concentration and absorbance. The whole process is then carried out individually by each student starting from the stages of designing, utilizing, and reviewing this simple spectrophotometer. Students' understanding of spectrophotometric concepts increases because each student follows the process thoroughly from the beginning to the final stages of the spectrophotometry practicum. Thus, it can be deduced that the application of RGB-ColorMeter can be used as a simple and accessible spectrophotometer in the spectrophotometry practicum at the Vocational High School of Chemical Analysts.

Unmanned Aerial Vehicle (UAV) is burgeoning technology for conducting aerial photography ranging from recreational purposes to engineering works. Due to its physical design, a mounted camera onto the UAV body is afflicted by engine and other vibrations during flight data acquisitions. In such condition, it is impossible to maintain the camera optical axis truly vertical while it is directed downward to the ground. Unavoidable aircraft tilts causes captured images to be exposed with the camera axis tilted slightly from vertical. In survey and mapping activity when vertical images are intended, the amount by which the optical axis deviates from vertical of more than 3 degrees is not met the work specification. Truly vertical images are necessary for producing high quality map from aerial images. This paper offers robust solution to rectify tilted images to generate equivalent truly vertical ones. We use exterior orientation parameters of the tilted images to perform double steps of transformation while resampling grid tessellations of the vertical images. To visualize the result, the transformation processes are coded by C++ programing language. The program results show a feasibility of our approach.

Today, off-the-shelf digital cameras are hand on tools for conducting visual inspections in surveying and mapping related activities or in structural inspection of industrial objects. Dense point clouds of the inspected object surface are of typical data required and their accuracies are also become more demanding. Deriving these data are off particular interest of this paper instead we work on overlapping images for generating those ones. An imaging geometry of stereo images is exploited further to reveal some drawbacks of the normalized stereo imaging configurations. We utilize a photogrammetric collinearity condition to model physical reality of the imaging process. A sequence of coordinate axes rotations on both images is rearranged as well as preserving normalized images resolutions to be equal to the source ones. Also based upon the prescribed resolutions, an efficient indirect resample is performed to interpolate grey values of the warped images. To ascertain reliability of the mathematically developed method, C++ programming codes were written and implemented in the solution. It reveals that a nuisance such as y-parallax is completely eliminated. Therefore, by using our method, the normalized images can be used in the dense point clouds production in a high quality and efficiency.

The purpose of the study is to develop the information systems (IS) for SMEs as well as to investigate the factors that influence the decision of SMEs to adopt information technology (IT). Using a development research approach, it focuses on developing the Web-based Decision Support System (DSS) IT on SMEs, with the Waterfall model's implementation. Structured interview (by phone) was conducted with 120 SMEs, and the results were tested using Confirmatory Factor Analysis. It shows that the implementation of the Web-based DSS for SMEs provides benefits for them as a database for management decision-making tools. In addition, it is also beneficial to the Indonesian policy makers in regards to the empowerment of SMEs. The findings of the study confirm the Technological, Organizational and Environmental (TOE) framework, that the decision to adopt IT by SMEs in Indonesia are influenced by technological factors including consideration of benefits, compatibility, and costs; organizational factors include the readiness of companies to adopt technologies including technological infrastructure readiness, relevant systems, and technical skills; environmental factors include customer/supplier pressures and competitor pressures. The findings also show that different sector of SMEs (manufacturing and service sectors) has different considerations in deciding the implementation of IT.

This study aims at developing multimedia instructional material at the elementary school level by using the MDLC (Multimedia Development Life Cycle) model. This research developed multimedia platform which consisted of learning modules and videos. MDLC constitutes methods consisting of concept, design, collection of materials, assembly, testing, and distribution. In developing multimedia by using MDLC, it was based on a flowchart system and a learning video story board. The results indicated that the multimedia developed was in accordance with the MDLC steps. Based on the results of alpha and beta tests, it indicated that the e-learning multimedia developed is feasible and practical to be used by elementary school students. Multimedia that was developed employs a variety of learning sources that are able to enrich student's knowledge in a more interactive presentation.

This study defines the problem of how understanding health protocols during a pandemic is correctly conveyed according to age levels. This problem for the Government to implement gamification by modifying game media through snake and ladder game that can socialize health protocols for pre-school. Measuring the acceptance of a snake and ladder game media can be considered as a learning medium from the Government which will refer to four components (game content, ease of play, appearance, and active player involvement). The purpose of this study was to modify online-based games as a learning media and to measure children's active interaction with parents in practicing health protocols during game play. This study will use a quantitative approach with data techniques through playing together experiments and filling in online research questionnaires from 115 samples as participants (7 Kindergartens). The results show that the snake and ladder digital game can have a significant effect on changes behavior in implementing health protocols. This research can provide a contribution that can be used as a reference for the Government to design a strategy for socialization through gamification.

Data mining is a method for finding hidden data from big data which has been continuously applied in various fields such as marketing, education, bioinformatics and so on. Drug store is one of the business sectors that might take the advantage of the data mining. In the drug store, there is a sales transaction data which contains a big number of data. However, there is a limited number of analysis based on this sales transaction data. There are several information that can be obtained from this big data; one of them is the combination of items that consumers often buy. Apriori Algorithm is a data mining method that has been widely used in order to determine the combinations of frequently purchased products. By using the Apriori Algorithm in the sales transaction data of the drug store.

Autonomous cars have become an interesting discussion in recent years. Several major automotive industries such as Tesla, GM and Nissan are trying to become pioneers in autonomous car technology. Giant technology companies such as Google Waymo, Baidu and Aptiv also developing autonomous car technology. Several technological approaches are carried out in implementing autonomous cars for recognizing surrounding situations, such as radar, lidar, sonar, GPS, and odometry. An automatic control system is used to control navigation based on the data obtained from these sensors. This paper will discuss the use of CNN deep learning algorithm for recognizing the surrounding environment in creating the automatic navigation required by autonomous cars. The system designed will create and learn the data set that will be taken in advance and the learning outcomes will be implemented in an open simulation system. This simulation shows high accuracy in learning to navigate the autonomous car by observing the surrounding environment.

Software testing is performed by executing test cases against the system under test (SUT). For researchers, it is slightly challenging to find real case SUT. As an alternative, researchers utilize the existing SUT from repositories as their research objects. Software-artifact Infrastructure Repository (SIR) provides some reasonably comprehensive SUTs that had been used by over 50% of software testing literature. Nevertheless, it is still rare among researchers to conduct profound studies of SIR's SUTs. This paper aims to fill the gap by explaining SIR's SUTs specification and how it's organized. Each of the C-language SUT was exposed and recorded its features comprising the size of SUT, lines of code (LOC), number of test cases, as well as the number and types of faults. SIR's SUTs divided into two parts namely "older" and "newer" objects which both provided with various versions of the test program as well as predefined test sets along with its specification. These results indicate that SIR's SUTs is carefully prepared to conduct software testing research.

This study aims to preserve the Takepan Sasak manuscript, studied and known by the public. This study uses evaluative methods and Kvisoft Flipbook Maker software. The process stages consist of data collection, analysis, digitization, testing and experimentation, and evaluation. The results of this study are in the form of a Sasak Takepan Manuscript flipbook which is expected to be accessed by the public digitally in a 3-dimensional model.

Urban green open space is areas in a city or town filled with vegetation to support socio-ecological functions. These areas have increasingly threatened as a result of being converted to urban infrastructures. As an essential feature of city infrastructure, urban green space should be monitored according to the spatial plan of the city area. However, the space that has been assigned to the urban green space is not a match for its current use. One of the problems that caused urban green space usage mismatch is difficulties in identifying urban green space changes. Planetscope satellite imagery is a high-resolution satellite image that can be used to identify open green spaces in urban areas. In this research, we used an artificial intelligence method to develop a pixel classification process for accurate and efficient identification of the green open space. The results showed that Planetscope satellite imagery and artificial intelligence methods had 99% accuracy in monitoring green open spaces. The use of this technology can assist in the early detection of green open space changes effectively and efficiently.

Less attractive and effective learning modules in thematic learning and less reinforcement in character education make students bored and do not really implement strengthening character education in the school environment and society. Therefore, alternative teaching materials are needed in thematic learning and strengthening student character education. The purpose of this research is to develop thematic modules based on PPK and QR code. This study applied the Bog & Gall development research model. The data analysis technique used was quantitative and qualitative data analysis. The research instruments used were observation, questionnaires and documentation. The results of research on the development of thematic modules based on PPK and QR Code, it is known that the results of the analysis of media experts obtained a score of 92.86 percent with a very valid category, material experts obtained a score of 88.64 percent in the very valid category, linguists obtained a score of 75 percent with a fairly valid category, the response of educators obtained a score of 89.92 percent in the very practical category, the response of students obtained a score of 87.78 percent in the practical category. Based on the results of the explanation above, the thematic module based on PPK and QR Code can be used as a supplementary teaching material for the thematic book to make it easier for students to acquire the lesson content and apply characters education in schools and communities.

Proteus professional is a group of electronic software used to assist designers in designing and simulating a circuit electronically. This software has two functions at the same time in one package, one package as software for drawing automatic schematics and can be simulated which is named ISIS. The second package is used to design the Printed Circuits Board (PCB) image which is named ARES. Directly, the conversion from schematic to PCB can be done in this Professional Proteus software. Prof. ISIS Proteus has always friendly versions, starting from version 7.0 to 8. Each version increase with the addition of library components that can be taken and used in drawing or designing. As an electronic frame designer, he first used ISIS as a medium that made it easier to play and simulate. A large number of libraries of the Proteus Professional ISIS on ISIS software is said to be a complete simulation software, namely from active components, Analog, Transistor, SCR, FET, types of buttons, types of switches/relays, digital ICs, amplifier ICs, programmable ICs (microcontroller) and IC memory. Apart from being supported by complete components, it is also supported by the completeness of measuring instruments such as voltmeters, ampere meters, oscilloscopes, signal analyzers, and frequency generators. The completeness of the features provided makes Proteus Professional ISIS into an electronic simulation software Emulator writer is a service text media for writing programs, especially using digital number codes, and can be collaborated with proteus, which is a window form media designed by the author to make it easier for beginners who want to learn about microcontroller programming, can be used to write programming/coding with code Binary and Hexa numbers are made in Indonesian with the aim that beginners who are just starting to learn about digital-based programming if there are errors in writing, instructions, or writing procedures, it will be shown in an Indonesian warning.

Weather is highly influential for human life. Weather anomalies describe conditions that are out of the ordinary and need special attention because they can affect various aspects of human life both socially and economically and also can cause natural disasters. Anomaly detection aims to get rid of unwanted data (noise, erroneous data, or unwanted data) or to study the anomaly phenomenon itself (unusual but interesting). In the absence of an anomaly-labeled dataset, an unsupervised Machine Learning approach can be utilized to detect or label the anomalous data. This research uses the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm to separate between normal and anomalous weather data by considering multiple weather variables. Then, PCA is used to visualize the clusters. The experimental result had demonstrated that DBSCAN is capable of identifying peculiar data points that are deviating from the 'normal' data distribution.

Rainfall greatly affects human life in various sectors including agriculture, transportation, etc. and also can affect natural disasters such as drought, floods, and landslides. This situation prompts us to build an accurate rainfall prediction model so that prescriptive measures can be made. Previous research on rainfall prediction uses models that have their limitations and thus produce poor performance. This study aims to build a multivariate rainfall prediction model using the best performing technique to date namely the Extreme Gradient Boosting. This model is built based on 7 years of historical weather data collected by the weather station. The result had demonstrated that the model is capable of producing accurate predictions for daily rainfall estimates with training RMSE of 2.7 mm and the testing MAE of 8.8 mm.

Designing mobile-app-based learning media is challenging for educators with minimal programming skills. This paper aims to introduce a conceptual model as a framework for designing learning media. In this paper, we discuss steps by step a mobile-app-based learning media designer by using glide apps. Descriptive qualitative with literature review design was used in this article. Based on the literature review, it can be known that glide app can design a mobile app which easy to use, build without code, applicable for the m-learning era, and used for free. However, the creation of a mobile app in education should be careful, because it needs to be adjusted to the age level and psychological characteristics of students. Therefore, educators can use the glide app as an alternative to m-learning media designers.

Regression testing is a testing process for established software and developed ones. Adding features to the software should not cause errors in the previous software version. There are several methods for implementing regression testing. The most straightforward is to do retest-all, but this technique is costly and protracted because it has to execute all test cases in the test suite. This situation is the nature of regression testing research, i.e. determining how to execute only a few test cases to shorten the time, and the faults can be found as much as possible. Recently there are various algorithms for regression testing process. This paper explains an empirical study of several regression testing methods. In the empirical evaluation, we used open-source SUTs, and several are implemented ourselves. On the other side, we utilize an MTS tool from the software artefact repository (SIR) and other open-source tools to automatic testing execution. The empirical study shows that each technique has a specific characteristic, and also has effectiveness significantly to reduce execution time testing process. So that in the regression testing implementation, it is crucial to determining the techniques considering each of them has consequences.

The purpose of this research was to describe the development of worksheets based on Sigil and Powtoon. This research and development used ADDIE Model. The research subjects were III grade elementary school students. The data collection instruments used a validation sheet and a questionnaire. Data analysis techniques used qualitative and quantitative data. The results of the evaluation of material experts and media experts obtained valid criteria with an average score of 86.36% for material experts and 87.5% for media experts. The responses given by students on this worksheet were 92.91% in the "very interesting" category. Based on these findings, it can be concluded that Sigil and Powtoon-based worksheets are suitable for use as instructional materials.

Diabetes is one of the most common health problems in the world. Diabetes is also known as "the silent killer" because according to WHO (2016) diabetes increased from 108 million in 1980 to about 422 million adults had diabetes in 2014. If not handled properly, diabetes can become chronic and damage other organs and can cause death. This disease has several symptoms in the patient but evaluating the different factors or symptom variables required to determine which variables are more dominant. This research aims to establish the most influential variable of the many variables causing diabetes mess. We suggest using a data mining decision tree (C4.5) in this paper to forecast diabetes to help doctors analyse the disease sooner. Data mining has carried out various approaches to predict a disease, one of them is the use of c4.5. In this research, produce a decision tree and the result shown that polydipsia play a role in diabetes with accuracy 90.38 %. One of the most dominant signs of diabetics is the sign of polydipsia.

Letters are an essential means of communication in an institution or organization, and they are closely related to the times' progress that cannot be abandoned, including today's digital era. Based on observations, letter archiving at Hamzanwadi University is still conventional and not digitally recorded. So this research aims to design a letter archiving application by applying the Model View Controller (MVC) concept with a development model using ADDIE (Analysis, Design, Development, Implementation, and Evaluation). This Design consists of system architecture, flowchart, data flow diagram, and ERD.

Nowadays mixing one language with another language either in spoken or written communication has become a common practice for bilingual speakers in daily conversation as well as in social media. Lexicon based approach is one of the approaches in extracting the sentiment analysis. This study is aimed to compare two lexicon models which are SentiNetWord and VADER in extracting the polarity of the code-mixed sentences in Indonesian language and Javanese language. 3,963 tweets were gathered from two accounts that provide code-mixed tweets. Pre-processing such as removing duplicates, translating to English, filter special characters, transform lower case and filter stop words were conducted on the tweets. Positive and negative word score from lexicon model was then calculated using simple mathematic formula in order to classify the polarity. By comparing with the manual labelling, the result showed that SentiNetWord perform better than VADER in negative sentiments. However, both of the lexicon model did not perform well in neutral and positive sentiments. On overall performance, VADER showed better performance than SentiNetWord. This study showed that the reason for the misclassified was that most of Indonesian language and Javanese language consist of words that were considered as positive in both Lexicon model.

Data mining (DM) is the process of extracting knowledge from data. Knowledge from customer behaviour segmentation is useful for companies in setting the target market and developing a marketing strategy. Recency Frequency Monetary (RFM) model is the most behaviour segmentation used. Many customer-segmentation studies in various application areas use the RFM model that collaborates with DM. With many methods in DM, the selection of appropriate methods can reveal useful hidden patterns in customer segments. This paper aims to analyse DM methods that collaborate with the RFM model and synthesize them to propose a customer segmentation framework. This study uses a comprehensive literature review published in 2015-2020. The most widely used methods are clustering and visualization from seven DM methods analysed. Due to the increased visualization function and the need for customers' geo-demographic data to be considered in the analysis, this study presents a new framework for using DM methods with the RFM based segmentation in the Geographic Information Systems (GIS) environment. This framework helps analysts utilize DM methods to uncover and understand customer characteristics, so companies can set the target market and develop a marketing strategy to increase their competitive advantage.

Probing of a question between two methodologies of the multiplicative model of Time Series and Fuzzy Relation is challenging to answer, without exploring each of both theories. This paper aims to discern any discrepancies or similarities in them, since each has detailed items that could lead to practical advantages to proceed on forecasting or decision making. Pseudo coding is a chance to explore theories and to surface those practical advantages. The finding states that the multiplicative model of time series factually has components that could have dependencies one to another, and the fuzzy relations help to map each point along their processes to determine how much dependency contained in the system that could conclude of a decision making.

In reality, students learn via eLearning (electronic online learning) system in different ways depending on their learning needs, learning behaviours as well as eLearning system policy for users. However, most learning outcome prediction models of eLearning systems are still not stable and still cannot be applied in many situations as the use of eLearning is considered to be highly dynamic. Therefore, the objective of this work is understand if eLearning system can be predicted based eLearning usage by exploiting Moodle log data. To understand it, features from web log course-student in Moodle is being considered, a number of machine learning techniques also have been applied for benchmarking in this study. The result found that the current group doesn't give better understanding and significant groups of factors that could be able to predict the learning outcome.

The Apriori Algorithm is an algorithm that is well known for performing frequent itemset searches using the association rule technique. The Apriori algorithm uses knowledge about the previously known frequent itemset to process data related to borrowing books in the library to be processed into useful information. This study uses a priori algorithm method for grouping books at the PGRI University Library in Semarang based on trends that appear together in a library activity visit. By gaining knowledge from this algorithm, it can be used as a reference for the PGRI University Library in Semarang in placing book collections.

The research aim to develop android games for use in learning Javanese vocabulary for children age 5 (five) to 6 (six) years. Methods used in android game development use models research and development (R&D) with ADDIE development model. Use 5 stages: analysis (analysis), Design (Design), Development (production), Implementation (Implementation) and Evaluation (Evaluation).The result of this development is an android game named "Sinau Basa Jawa". Android Game contains interesting features in the form of agency or control, interactivity, feedback, curiosity challenge, identity, immersion, fantasy. With 2D graphic evolution. The results of this study were tested toward media experts, early childhood education specialists, Javanese language expert, kindergarten teacher. The quality of this media product is seen from the aspect of material and media feasibility. The result with media outcomes that are declared very feasible. Android game "Sinau Basa Jawa" very suitable applied for education Javanese language. android game can help teacher and parents teaching Javanese vocabulary to children.

Augmented reality (AR) is a technology that can be used in the classroom. This study aims to create an AR application and pilot the AR application in the vibrations and waves learning. Furthermore, to see if there are differences in the learning interest and physics learning outcomes by using the AR application in the learning process. The research method used to develop this application is by adapting the 4D Thiagarajan model (Define, Design, Develop, and Disseminate). The result shows there are differences in physics learning outcomes and learning interests of students studying physics using AR. AR and the use of media can be a solution for learning physics in the future.

The Office of Communication and Informatics of Blitar Regency carries out its main tasks supported by temporary personnel with their respective work targets. To find out the number of performance targets that have been carried out and performance appraisals per year, the temporary staff must make daily and monthly performance reports to the leadership. So far, technical reporting uses Microsoft Excel which must be printed one by one before being reported. If there are errors on the report must edit one by one. Each sheet stores daily reports so that many sheets are used to store reports in one month. Reports submitted to the leadership are still in copy which is prone to loss. This has a negative impact on the deadlines for collecting reporting and monitoring by the leadership. Based on these problems, a Web-Based Performance Reporting Information System was built to optimize performance reporting. The system is built with 3 access rights: admin, leadership, and non-permanent personnel, employee mastering and performance targets with targets, as well as daily and monthly reporting transactions. From the test results, the system with UAT 89.8% has been able to optimize performance reporting with the output of performance values per month and per year completed with graphs of performance targets.

Malaria can be difficult to detect from thin blood smears. Image recognition methods such as convolutional neural network can be used to detect malaria, but the training process takes a long time. Previous research created a new architecture and compares it to several other architectures such as VGG-16 and ResNet. The effect of preprocessing is analyzed in this research. VGG-16, ResNet, and the custom architecture created by the previous research are being used in this study. The preprocessing methods being analyzed in this research include gray-world normalization and comprehensive normalization. The highest accuracy improvement per epoch (0.5256% using ResNet-50 and 0.0352% using custom architecture) is achieved through gray-world normalization, that also improves final accuracy (90.1% using ResNet-50 and 93.1% using custom architecture) when compared to other methods with the same epochs for ResNet and custom architecture.

Tuberculosis is a serious infectious disease caused by Mycobacterium tuberculosis (MTB) that primarily affects the lungs. It is known that several strains of MTB are resistant to drugs used in the treatment. This situation calls for the importance to detect and prevent further drug resistance and thus reducing the mortality rate. The conventional molecular diagnostic test is costly, requires a long time to conduct, and has low prediction ability. This research aims to explore the Machine Learning approach to accurately predict drug resistance which offers a much faster and cheaper solution than the conventional one. Experiments were carried out on 3393 isolates of MTB using several Machine Learning algorithms including C4.5, Random Forest, and Logitboost. Multiple drugs evaluated in this study include rifampicin (RIF), isoniazid (INH), pyrazinamide (PZA), and ethambutol (EMB). By using 10-fold cross-validation, the result had demonstrated that the model can accurately predict drug resistance with an accuracy of 99% and with Area Under Curve (AUC) reaching (near) 1. This result suggests that Machine Learning approach has a promising result in predicting Tuberculosis drug resistance.

Food production in Indonesia is very strong and constrained, such as rice, corn, eggs and so on. Eggs that are consumed every day by Indonesian citizens, many consumers of egg food are not alert to the condition or condition of the eggs, whether they are feasible or expired. There are many studies related to the nature of eggs, egg quality and others, in part there is no modeling tool for detecting egg quality conditions based on raspberry pi using the K-Nearest Neighbor method which can be used to see good or bad eggs. In this study, the Raspberry Pi was used as the main component with the aid of a camera as an image capture on eggs using training data of 100 egg samples consisting of 50 good eggs and 50 bad eggs in order to get maximum accuracy. With the help of 2 led as a light source and the software uses the Python language. The purpose of this study was to obtain the expected accuracy by collecting 20 eggs randomly to get a percentage (17/20) * 100 = 85%.

Moodle is one of online Learning Management System that can be downloaded and installed on our server for free. Moodle is suitable solution for universities to organize online learning. Changing all learning activities from offline to online during a pandemic situation, especially for universities, requires Moodle services to be reliably available. The more students it means the more traffic should be handled by Moodle server. Moodle consists of system, user's data and a database. To increase Moodle reliability, we can rely on these components. We can use virtualization technology to simplify migration system and recovery process. Distributed file system technology is a best solution to store Moodle user data because it can be replicated into several nodes and support for high availability. Finally, the last component of Moodle is a database, we can replicate the database into several machine to increase availability. At the top of every Moodle component, we need cluster control to make sure all of Moodle components can be accessed. The results show that with the right fault tolerance strategy, all requests can be responded to 100% without error. In addition, this strategy can also increase the response time 12 times faster when compared to a single server.

The problem in this study is that the use of technology has not been optimal in developing village potentials associated with opportunities for village innovation programs. The problem arises because not all villages have the same capacity in aspects of the potential and capacity of village officials, so that in response to this policy the village innovation program is an alternative solution to the problem of inequality in capacity, resources, and so on. This study uses a dynamic model of village development and innovation to analyze technology-based village innovation governance in new autonomous regions. The method used is a qualitative method which relies on secondary data with descriptive data analysis techniques. The results show that the factors in the dynamic model of rural development and innovation are based on internal and external factors. Internal factors include human resources and knowledge, information and communication, community participation, leadership, local wisdom, local potential, experience, challenges and obstacles. External factors include legal umbrella, networking and cooperation, government support, as well as appreciation and incentives.

This study aims to determine the level, correlation, and influence of the usability of academic information system services using the ServQual and WebQual 4.0 methods. The research method used is qualitative-qualitative and data collection through a survey verification consisting of 20 statements. The questionnaire statement uses a Likert scale with 100 student respondents as the main users. The sampling technique uses a simple random sampling technique. Then, the data analysis in this study uses path analysis. The results showed that ServQual was at an average score of 2.60, WebQual 4.0 was at an average score of 2.59, and the average score for the User Satisfaction variable was at 2.66. Academic information system improvement will have a major effect on User Satisfaction. This is by the results of the verification analysis which shows that ServQual (X1) and WebQual 4.0 (X2) have a positive effect simultaneously on User Satisfaction (Y), with a total effect of 0.688 or 68.8%. External influence of 0.312 or 31.2%. Thus, the academic information system in small and medium-scale private universities needs to be improved on the WebQual 4.0 variable and can be added by ServQual improvements, and ServQual improvements can also be done without including WebQual 4.0.

Regression testing is one of the essential activities in software development. Regression testing ensures that the software is still working properly and new software modifications do not cause unexpected defects. Most of the software industry carries out regression testing on the system under test (SUT) by utilizing tools automatically rather than being done manually which requires a long time estimation and ineffective process. Currently, there are many regression testing tools and variations that make software practitioners need additional time and money to analyze the capabilities of the tools. This paper is a comparative study of the capabilities of tools in carrying out the regression testing process in the java programming language. Each tool has experimented with user input data in the form of a SUT program and a test case that has the same characteristics. Furthermore, the tool's performance is observed based on the feature evaluation criteria. The criteria used are support platform and technology, test case selection, and functionality. The results showed the similarities and differences in the features of the selected testing tool in performing regression testing. Thus it can help users to choose regression testing tools that suit their needs.

This research is motivated by the importance of skill assessment in pharmacy physics laboratory learning. In general, laboratory skills assessments do not have a specific standard for each assessment. When students perform their performance and skills in doing practicum, they are not well observed and measured. An alternative assessment that can measure a pharmacy physics laboratory's skill is to use a performance assessment. This study aims to design a digital performance assessment application that can be used to assess student laboratory skills. The development of a digital performance assessment application uses the Waterfall Model Software Development Life Cycle (SDLC) approach, which consists of the main stages of needs analysis, system and software design, system implementation and testing, and maintenance. The digital performance assessment design generally consists of an assessment instrument database and a user interface. Lecturers, as experts, are tasked with making assessment instruments. Meanwhile, the user interface is used by laboratory assistants/instructors to provide skill scores during student practicum. This application is then integrated with the existing web-based electronic module (e-mulsi). In the end, students can see the overall practicum score. The design of a digital performance assessment application is an alternative in a learning assessment platform that is more interesting, actual, and able to present real-time information on practicum learning in the laboratory. Policymakers are expected to consider integrating the use of these applications into a practical learning curriculum.

South Garut has tourism potential areas in Indonesia. However, the lack of government attention and information of the tourist area in South Garut resulted a lack of tourists coming. South Garut tourism will be more accessible by developing an information system that implements the Android system as a promotional medium to introduce tourist objects. This study is undertaken to design an Android-based BD-Print application to assist the development of the regional potential tourism sector in the Southern Garut. The BD-Print system development will use the System Development Life Cycle approach with the Waterfall method. This application has gone through several process such as planning, system analyzing, crafting, implementation, testing and development. Result of the experiment are: 1) The application programs created by using Android run well. 2) The features existed in the application program runs well as the main menu displays other menu options, login menu, tourism menu that displays some options of available tourist destinations, and mapping that displays the route from the current location to the location of the object destination tours. 3) This BD-Print application suits well as a reference for tourists that are going on a vacation without being accompany by tour guide.

Entrepreneurship has been proven in various researches in the world to help improve the welfare of society by creating jobs. Many universities in the world have adopted entrepreneurship in their curriculum designs in the form of entrepreneurship education. Besides, the technology fit task variable is also important in increasing student entrepreneurship intention. Therefore, research on entrepreneurship intention (EI) and the factors that influence it among students is very relevant. This study aims to fill the knowledge gap in the effect of task technology fit (TTF) and entrepreneurship education (EE) on entrepreneurship intention (EI) by using the theory of planned behavior (TPB) model. The research sample was 213 undergraduate students at one of the private universities in Yogyakarta selected by the Slovin method. Data were collected through a questionnaire shared with the student by MS Form. Regression analysis tools were used to test the research hypothesis. These results prove that H1, H3a, and H3b have a positive effect on EI with different levels of significance. Meanwhile, H2 has a negative influence on EI. This study has contributed to filling the knowledge gap that TTF and EE can be integrated into the TPB model.

In this study, a mapping of the potential for agribusiness in the southern part of West Java was carried out, which serves as a policy material and business development in developing local potential in the agribusiness sector to improve local communities' welfare. West Java Provincial Regulation Number 12 of 2014 divides the Southern part of West Java into three Growth Center (PP) zones, namely PP Palabuhanratu, PP Rancabuaya, and PP Pangandaran. The agribusiness potential of South West Java is dynamic and varied. However, it has not been developed optimally to improve local communities' welfare, which is generally scattered in underdeveloped villages. The government and developers (entrepreneurs) have difficulty obtaining digital data updates. The purpose of this research is to map the regional potential in the field of agribusiness in the form of digital data to facilitate the development of agribusiness potential in coastal areas located on the shores of the Indian Ocean (Indonesian Ocean). The research method uses Geographical Information Systems. The results showed that the potential and variants of agribusiness in PP Palabuhanratu are spread across 5 districts. In PP Rancabuaya spread into 5 districts. Meanwhile, PP Pangandaran is spread over 5 districts. This research can be used as policy materials and business development in developing local potential in the agribusiness sector to improve the welfare of the people of West Java.

There are many criteria and alternatives in determining recommendations and mapping of SMEs, so a decision-making method is needed. The SMART method is a multi-criteria decision-making technique where each alternative consists of number criteria that have values and describes how important the criteria are compared to other criteria. This weighting is used to assess each alternative in order to obtain the best alternative. Industry 4.0 criteria used are owner education, production results, information technology certified employees, having a marketplace, online payment facilities, online marketing media, e-commerce systems and information systems for SMEs. The purpose of this study is to map SMEs in Bangkalan into 4 levels in order to carry out work programs in the face of the 4.0 industrial revolution using the adaptive SMART method. The results of this study are 35% entered the mature readiness stage of Industry 4.0, 28% entered the early readiness stage and 37% entered the intermediate readiness stage readiness stage. Accuracy results the feasibility of the system by the SMEs cooperative office and SME players was 91.15 %.

The nitriding process can be effectively applied to steel with alloying elements. The higher the alloying element in the steel maximizes the mechanical properties, including hardness. However, the raw material can be costly, therefore using cheap materials (without alloys) is a challenge in increasing surface hardness through iron nitride formation. Furthermore Grey and nodular cast iron have different properties and characteristics in the structure. This research focuses on the ability of the cast-iron structure to affect the nitride layer formation. Gas nitriding was conducted in a fluidized bed reactor with a 550°C in 20 % N₂ and 80 % NH₃ atmosphere at a flow rate gasses of 0.7 m3/hr process temperature and holding for 2, 4, and 6 hours. Tests are conducted by observing the depth of hardening, SEM, and EDAX. According to the results, the nitriding process increases the surface hardness of cast iron. The highest hardness value is nodular cast iron with a holding time of 6 hours (345 HV) and a hardening depth of up to 20-micron meters. The compounds formed in the nitride layer include FeN, Fe_2-3N, Fe₄N, and Fe₂N. The compound formed is strongly influenced by the treatment time. Furthermore, the comparison of nitriding treatment on gray and nodular cast iron was influenced by the flake and nodule structure. In general, the nodule structure is responsible for maximum hardness. The longer treatment time allows the nitrogen atoms to diffuse more to the surface, while the flake structure limits the absorption of nitrogen atoms into the surface of the cast iron. Characterization of Nodular Cast Iron shows that The hardening depth distribution trend due to the nitriding process in nodular cast iron was not much different from gray cast iron.

This study aims to analyze the effect of deproteination temperature on the chitosan adsorption for iron metal ions in Bangka post tin mining water. Extraction of chitosan was carried out in four steps: deproteinization, demineralization, decolorization and deacetylation of chitin. The effect of deproteinization temperature on deacetylation process was studied. The results shown that the increase of deproteinization from 30°C to 90°C causes the decrease of chitosan deacetylation degree (DD): 65.72%; 64.31% and 63.75% respectively. The increase of deproteinization temperature triggers excess depolymerization which damages the chitin structure so that it has a negative effect on the chitosan DD. The metal content of iron in post tin mining water sample this study reached 6.1 ppm. Adsorption of chitosan on iron metal ions reduced the dissolved levels reaching an average of 99.67% from the initial content. The adsorption of iron lead by chelation mechanism. The reaction of chitosan with iron metal ion lead the formation of complex compounds with chitosan as a ligand and metal ions as the central ion. Based on the ligand strength series in spectrochemistry, the hydroxyl functional group is to the left of the amine group, so that the amine group is stronger than the hydroxyl group in adsorbing metal ions. It is more likely to predict that the valency forces through the sharing of electrons between transition metal cations and adsorbent are the adsorption behaviour may involve.

At present, spatial analysis has been used on epidemiology. Spatial analysis was used to determine the environmental risk that influence to transmission of Filariasis. The aim of the study was to identify, at industrial area, the environment determinant that are associated with Filariasis cases in Pekalongan City. The geocoding method was applied on the prevalence of cases to determine the pattern of spatial. Spatial autocorrelation was used to determine the effect of the environment on filariasis transmission. The kernel method was used to determine the density of filariasis cases. Based on the spatial analysis, the statistical values associated with the correlation between the risk of filariasis transmission and environmental factors were obtained. The correlation value of the influence of the environment on the transmission of Filariasis was statistically significant, this coefficient is 0.312. The value of R indicates that the spatial pattern of filariasis cases forms a cluster pattern. The Moran's index calculation obtained a positive spatial autocorrelation value of 0.44 with z-score is 16.05 and P-value is 0.00. Spatial autocorrelation was useful to determining the level of risk transmission of filariasis in Pekalongan City which may help to adopt effective control strategies in filariasis eradication programs in Pekalongan City.

To review the recommendations for the production of novel red phosphor materials, in this work we established the multiplet energy diagram of Mn⁴⁺ in a-Al₂O₃ under pressure. By the discrete variational multi-electron (DVME), the calculations were conducted based on many-electron approaches. Since the experimental data of Mn⁴⁺ in a-Al₂O₃ at zero pressure was the only data reported so far, the results in this work are our predictions. The effect of increasing pressure is naturally similar with the effect of decreasing bond length. This work indicates that the multiplet energies responsible for the absorption process increase as the pressure increase. Whereas, those responsible for the emission process decrease. These tendencies are the same as our previous calculations on a-Al₂O₃: Cr³+.

Energy derived from fossils is diminishing and cannot be renewed. Therefore many experts are looking for other alternatives to create new renewable energy, and Dye-sensitized solar cells (DSSC) are one of them. This study aims to know the characterization of the electrical properties of dye cosmos caudatus material. The research was conducted at the UNS FMIPA Materials Laboratory. This research uses the TiO₂ deposition method with the spin coating technique. Absorbance test using PC UV Visible Spectrophotometer 1601 and Current and voltage test (I-V) using Keithley. The efficiency produced by the Cosmos caudatus chlorophyll dye was 8.3 × 10⁻³ %. These results show that some natural dyes from natural organic material extraction have an absorbance spectrum range of 300-800 nm, which has the potential as DSSC.

The purpose of this study was to determine the concentration of urine solution as a watering medium and organic fertilizer on the productivity of hydroponic corn fodder. The research materials were corn, sheep urine, and water, while the method used was field experiments. The treatments, namely T0 (0% urine), T1 (5% urine), T2, (10% urine), T3 (15% urine), T4 (20% urine). The variables were the percentage of germination, percentage of normal sprouts, number of leaves, plant height, fresh production and dry matter production. The data obtained were analyzed using analysis of variance, if there is an effect, then continue with the LSD test. The results showed that the treatments had a very significant effect (P <0.01) on the percentage of germination, percentage of normal germination, number of leaves, plant height, fresh production, and dry matter production. The highest germination percentage was found in T1 (91.60%), normal germination percentage T1 (86.78%), number of leaves T1 (3.0), plant height T0 (31.6 cm), forage production T1 (646.6 grams), dry matter production T1 (568.41 grams). Based on the results, it was concluded that watering with 5% concentration of sheep urine solution gave the best value for the productivity of hydroponic corn fodder.

Self-regulated learning is needed to regulate and direct itself, adjust, and control self-learning. This study aims to get an overview of students' self-regulated learning in solving junior high school mathematics problems. This research is a qualitative descriptive study with three research subjects. The data collection techniques used math ability tests, problem-solving tests, self-regulated learning questionnaires, and interview guidelines. The results showed the profile of self-regulated learning raised by junior high school students when solving math problems, especially problems related to SPLDV, namely: 1) Planning, thinking and activation stages: (understanding the problem is expressed in using one's own language or the language of the problem and there is an estimate of SPLDV completion through arithmetic procedures, logic and elimination substitution methods; 2) Monitoring Stage: monitoring is carried out on the correctness of the variables with or without involving the whole conversation; 3) Control stage: answer checking with reverse technique; and 4) Reaction and Reflection Stage: Explore the difficulties faced related to routine and non-routine problems.

In geometric topology, it is very interesting to develop especially related to the visualization of similar polygons to show the existence of each topology in a two-dimensional plane (R2). The aim to be achieved is to evaluate the conceptual application through the application of the development of the theory of polygon duplication images that are similar with the aided triangle and rectangle. The method chosen in this study is basic research for aiming at discovering new knowledge that had not been previously known. of a visual illustration of a polygon where the number of duplications can be determined and the R2 field. The instrument used is a validated assessment sheet. The validity test result is 2.68 so it is included in the valid category. The visualization of polygon topology on R2 can determine the number of polygons produced by dividing the number of corner points (n) into 2 parts, namely even and odd. The phenomenon of the research result shows that the odd and even n shows an arithmetic sequence. With this division, the formula for the total polygon topology ∑ ?_? is obtained using the formula for (Un) in the arithmetic sequence.

Phytoplankton growth model has been observed extensively to track the movement of elements through aquatic food webs and ecological processes. This study is purposed to find numerical solution of The modelling of phytoplankton growth and know the dynamic behavior. The method used to transform the phytoplankton growth model is Finite Difference Euler Method. We focused on the existence and stability of the fixed-points. We break into two cases. The result is that all of cases is dynamically consistent with its continous model only for relatively small-step size. We present some numerical simulation to illustrate those cases. We break into two cases. The result is that all cases is dynamically consistent with its continous model only for relatively small-step size. We present some numerical simulation to illustrate those cases.

Covid-19 is part of worldwide pandemic since early 2020. Various mathematical models have been proposed to understand the behaviour of the disease, but most of them were failed to predict the biological phenomenon of this infectious diseases since they use incorrect assumptions due to early stage symptoms. The aim of this paper is to develop a covid-19 mathematical model with nonlinear incidence rate. We use some logical assumption to develop the model. We discretize the model by using Euler method. We use literature review in our research methodology. Then, we simulate the model by using computer software. We found that this model has two equilibrium points, namely disease free equilibrium point and endemic equilibrium point. The stability of the model is changed by increament or decreament of the step-size. If the step-size of the model is large enough, then it lead numerical solution to blown up. Finally, we also found that this model is fair enough to simulate the pandemic in our case. Also, we found some interesting phenomenon from our simulation that is the effect of government policies or social distancing. Further work is needed to analyze the stability of the model and the effect of delay.

This study aims to find out the effectiveness of using augmented reality-based magic book math at State Senior High School 15 Semarang on student achievement. The type of research used was Quasy Experimental research. The population of this study was X grade students of State Senior High School 15 Semarang. With random sampling technique, two classes were selected, X grade of IPA 4 as the experimental class and X grade of IPA 2 as the control class. Data processing with t comparative test and regression effect test. The results showed that learning was said to be effective which was indicated by: a) the average value of learning achievement in the experimental class was 89.57 which exceeded the Passing Grade 70 limit; b) the effect of student responses can be seen from the value of R square = 0.882 which means 88.2% of student achievement was influenced by student response factors in learning using magic book math based on augmented reality; and c) the average learning achievement of the experimental class was 89.57 while the control class was 70.84, so the experimental class had a significantly better final score average than the control class average.

Good learning outcomes supported by a good understanding of concepts. A good understanding of the concept is an understanding that do not contain misconceptions. This study aims to identify the misconceptions of prospective mathematics teacher on graphing function. This research was conducted on 8 undergraduate students. This study used a descriptive research design. Descriptive research is used to analyse conceptual understanding and student misconceptions based on test results using diagnostic test instruments and interview results. The questions used were 5 questions that had been validated by 2 mathematics lecturers with valid results. The results showed that most of the students were still doing plotting without identify of the domain dan characteristics of the function. Some of them were also still stuck with using integers as the reference.

One of the focuses of Indonesia's development is on the tourism sector. In addition, one of the supporters of the sector's sustainability is the customer. So, customer satisfaction who comes and their desire to come back again, as well as an indirect promotion to other potential visitors. The availability and convenience of infrastructure and facilities are important to support this. In other words, the prediction of visiting foreign tourists is one form of alertness in preparing future tourism projections. However, the fluctuation of data for foreign tourists affects the effectiveness of the model in making predictions. Kalman filter is a stochastic deterministic model that can solve this problem. This study combines the time series model with the Kalman filter to determine the prediction of the number of foreign tourists visiting East Java. The results of these predictions can be concluded that the Kalman filter is able to handle fluctuating data with RMSE close to 0. The prediction for this paper could be help enterprise to decide future plan for give the tourist discount.

Diphtheria disease remains endemic in some countries due to the lack of immunization coverage, such as Indonesia, where health care are something need to be pursued and optimized. In the last three years, there are still some areas in Indonesia that its complete basic immunization coverage are less than 50%. Apart from being caused by low immunization coverage, other factors as nutritional adequacy, environmental hygiene and virulence levels of the disease also influence the occurrence of diphtheria outbreaks. In this study, we propose a mathematical model that considers natural immunity rate of the exposed individuals in the spread of diphtheria. This study aims to understand the dynamics of the proposed model. The behavior of the system is known by analysing the stability of its equilibrium points. Numerical simulations using Maple are also carried out to illustrate the dynamics of the system. The stability analysis and numerical simulations show that the disease-free equilibrium point is stable if ?₀ < 1, whereas the endemic equilibrium point is only feasible and stable if ?₀ > 1. The results shown that complete basic immunization coverage and natural immunity rate of the population affect the basic reproduction number.

The purpose of this study was to describe the creative thinking process of students in reflector learning style in proposing and solving review problems from the Wallas stage. This research is a qualitative research. The subjects of this study were students of semester VII of the Mathematics Education Study Program of the University of Kanjuruhan Malang with the following criteria: a) age between 18-25 years, b) of the same gender, c) At least getting a B grade for the course of School Mathematics Development Studies. Researchers in this study acted as the main instrument and the supporting instruments used were Honey and Mumford's Learning Style Questionnaire (LSQ) questionnaire, test sheets, and interview guides. Questionnaires will be given to research subjects, and subjects with reflector learning styles will be selected. Based on the researchers' observations, it can be concluded that aperson with a reflector learning style will tend to prefer to observe, be careful in making decisions that will be seen at every stage of his creative thinking process.

The use of technology in learning needs to be encouraged starting from the elementary school level. Another thing that needs to be encouraged is local wisdom-based media to support character learning. This study aims to develop holobox augmented reality technology media of local wisdom of the Grebeg Pancasila rite for mathematics learning in elementary schools. This research produces multimedia based on technology Holobox Augmented Reality (AR) with the content of material Grebeg Pancasila for learning mathematics and building spaces in elementary schools. The method in media development using the Development Life Cycle developed by Luther consists of six stages, namely: concept, design, material collection, assembly, testing, and distribution. The media produced meets the standard of feasibility and can provide information and knowledge about understanding the concept of flat and space structures through the flag and gunungan symbols in the Rite Grebeg Pancasila. The implication of this study is that cultural diversity in local wisdom of the Rite Grebeg Pancasila can be used as a medium for learning mathematics in elementary schools (MI/SD) through Technology Holobox. Augmented Reality.

Many researchers research mathematical literacy, but there are no articles that discuss how research has developed over a certain period in Indonesia. This article aims to discuss how bibliometric analyses research mathematical literacy during Indonesia's last ten years. Besides, knowing the description of mathematical literacy research trends in the future. There were 46 bibliometric analyses of articles taken from the Scopus database. Articles were analyzed using Scopus Applications and VOSviewer version 1.6.12. The results showed that 46 articles analyzed in international journals were either still valid or discontinued by Scopus. Furthermore, the term mathematical literacy is most dominant in research and article writing. Finally, research on mathematical literacy is still up-to-date researched in the future, especially related to the learning and assessment process, curriculum development that supports mathematical literacy, and the involvement of teachers, parents, and society in supporting students' improvement' mathematical literacy.

A provided data from a transactional database, has supported technical development which can automatically find product association or items saved in the database. This finding association rules between saved product in database known as mining association rules. There are so many theories and algorithm developed for conducting mining association rules. One of algorithm developed is Apriori algorithm. This method, has a main goal to find the maximum frequent itemset. Next, this frequent itemset will be generated into associative rules which are not shown before in the database, become valuable information for considering materials in the decision process. Apriori algorithm is a interpretation technique of mining association rules, will be implemented into a web based software. On the software test which use in some different data, it's concluded that time for mining association rules depends on the presence of every item in every transaction, total of transaction, minimum support and minimum confidence. For smaller value of minimum support and minimum confidence that entered, program will generate more association rules, vice versa.

Problem-posing is the ability of students to raise the problem. Problem-posing ability is important, owned by students in mathematics. It is because integrative mathematics learning students need to do scientific activities. The scientific activities comprise observing, questioning, gathering information and communicating. By having problem-posing abilities, expected students to motivate to overcome the problems raised themselves. The purpose of this research analyze problem-posing ability in mathematics in third-grade students at the elementary school levels. The method used qualitative research using descriptive analysis. Here, problem-posing ability in third-grade students in mathematic is still low. It proved this by tests conducted in two elementary schools in Sumedang and got 37.7 and 42.5 scores. Based on the analysis of students' answers, there are some difficulties experienced by students, namely unable to answer what they know, they cannot find the most important problems, they could not overcome the initial problems, and make questions. The indicators in problem-posing interrelated, that is looking for most important problem by making questions. It is because students will make questions based on the important information which they have already known. With this research, the teacher can easily determine the teaching method by the teacher to improve students' problem-posing abilities.

3D Grapher application is a user-friendly application that supports learning to three-dimensional geometry. The purpose of this study was to determine the increase of students' mathematical spatial ability by using the 3D Grapher application. This study uses quasi-experiment method with a tutorial model conducted on class VIII students one of junior high school in Bandung City. The instruments research by test and the research data were analyzed by t-independent test. Based on the results of research that improves mathematical spatial ability of students who get 3D Grapher based tutorial learning with an average n-gain score 0,56 better than students who get conventional learning with an average n-gain score 0,44. Thus learning through the 3D Grapher application can be used as an alternative to improve the mathematical spatial abilities.

The purpose of this research is to improve the student mathematics learning outcomes through Kahoot learning games application at elementary school. This classroom action research adopted from Kemmis and Mc Taggart Model was conducted in three cycles for the fourth grade as many as 22 students at 02 Public Elementary school in Tomohon, North Sulawesi, in Indonesia. The result of this study shows there is an improvement of students learning outcomes from cycle one to cycle three reaching 64, 72, and 81 from the maximum score of 100. Percentage of teacher and student activities increased from cycle one to cycle three achieving 77, 80, and 86 %. It can be concluded that application of Kahoot learning games can improve the student mathematics learning outcomes at 02 Public Elementary school in Tomohon, North Sulawesi, in Indonesia.

This study aims to determine the learning of mathematics through light scales media from used goods. Students' understanding of weight comparison is still experiencing difficulties. Students often mistakenly distinguish heavy objects from light objects. Teachers have tried to make improvements through learning methods, but only 20% of student learning outcomes have been completed. Therefore, researchers conduct action research studies in the form of treatment for learning media applications. The research subjects were 30 first grade students. Data collection techniques in this study are through observation, tests, and documentation. The results of the study prove that the use of lamp scales media of used goods in mathematics learning that is in the initial conditions, 24 students have not reached skills, but in the first cycle, the number of students who have not reached mastery decreased to 15 students and in the second cycle all students have reached completeness. This study concludes that the use of media scales lamps from secondhand goods can develop mathematical learning understanding, especially in the theory of weight comparison.

The ability of creativity needs to be the focus in learning mathematics because achievements in learning mathematics develop students' mathematical creativity abilities. The purpose of this study is to determine the effect of the Missouri Mathematics Project model on students' mathematical creativity abilities. The research method used is an experimental method using purposive sampling techniques with instruments that use tests and questionnaires. The results of research on student responses in the Missouri Mathematics Project model obtained 87.72% who responded positively, with the value of students' mathematical creativity ability obtained 81.30 so that it can be said to be good. The research hypothesis test results obtained tcount> t_table (7.14> 2.02) that is the results can be accepted. The conclusion is that there is a positive influence on the Missouri Mathematics Project model with students' mathematical creativity abilities.

The purpose of this research is to design and create an educational game based on e-learning Matemathic on the Basic Concept of Counting. The method of this research is research and development. This research was conducted in DKI Jakarta Elementary School class V and the object of research was an educational game based on e-learning Matemathic in the Counting of Basic Concepts as a medium of mathematics learning. The method used in data collection is observation and documentation, and the method of data analysis is quantitative descriptive analysis techniques. The results of this study are in the form of an educational game based on e-learning Matemathic in the Numeracy Basic Concept Planting as a learning media for class V. Material expert validation of learning media material based on the quality of the material and the usefulness of the material gets a percentage of eligibility of 76, 56%. The assessment of media experts on the quality of instructional media is based on the characteristics of the media in learning multimedia gets a percentage of eligibility of 86, 68%. The results of the assessment on product trials are divided into three aspects, namely aspects of screen display design, program operation, navigation, and expediency. Overall assessment results of 68 grade V students obtained a percentage of eligibility of 92,94 % so that this learning media is appropriate to be used as grade V mathematics learning.

The lack of multimedia applications in schools and the low mathematical communication ability of students, as an alternative to using Android. The purpose of this research is to improve students' mathematical communication ability through android based learning project. Using the quasi experimental method. This research conducted at Junior High School in Bandung with 55 students as samples, 29 students in class VIII C as an experimental class and 26 students in class VIII D as a control class. Mathematical communication ability test instrument. Data analysis: independent T test, two way ANOVA test. The findings: Improved communication of students who get learning on Android based learning projects was higher than students who get conventional learning. There were no difference in the achievement of mathematical communication between students who get an Android based learning project and conventional learning based on mathematical basic knowledge in the high, medium and low categories. There is the influence of the interaction between the type of project based learning with android applications and expository learning and prior knowledge mathematics category (high, medium, and low) on the ability of students' mathematical communication. Android based learning project facilitates inventions process, reflective, the material is easy to understanding so that students' mathematical communication skills increase.

The low quality of students in mathematical connections requires learning processes using technology-based. The purpose of the study was to analyze the ability of mathematical connections between students learning scientific based on prezi, lectora-inspire and conventional learning. This study used a quasi-experimental method and a nonequivalent control group design. Involving a sample of 84 students from three senior high school classes which were divided into an experimental group and a control group as a test instrument for mathematical connection ability. The data analysis uses independent T-test, one way ANOVA, and post hoc least square differences test. The finding is that there are differences in the improvement and achievement of mathematical connection skills between students who carry out prezi-based scientific learning, better than students who have lectora-inspiration based learning and conventional learning. Prezi and lectora-inspire scientific learning facilitates students interaction processes to construct concepts, find problems, apply media, and reflect processes so that it can improve students mathematical connection abilities.

This study discusses how the notion of a function can be developed for high school students through the use various contexts that are close to students' daily life or make sense to them. The Realistic Mathematics Education approach provides the framework that guides the discussions. The concept of function has become one of the basic ideas in modern mathematics that underlies almost all disciplines. But it proved to be one of the most difficult concepts in learning mathematics. The concept of function is often taught without connecting to everyday context. Formal mathematical symbolism of concept such as f(x) introduced prematurely to students which can lead to learning obstacle about functions. The study provides mathematics educators a hypothetical learning trajectory as a platform which facilitates a Realistic Mathematics Education approach to teaching function especially to develop algebraic thinking skills.

This class action research was conducted to see the effectiveness of the flipped classroom method on improving the concept of addition and subtraction. Flipped classroom method was chosen because it is in accordance with the current development of digital learning media that utilizes technology in learning. Flipped classroom performed by providing learning videos that can be viewed online by students at home then followed by problem solving activities through discussion activities in class with mentoring provided by the teacher. Based on this study an increase of 28.6% was obtained so that 83.3% of 42 students scored more than the minimum competencies criteria. The implications of this research can be utilized in other mathematical learning concepts.

The problem in this study is the low Self-Regulatory Strategies (SRS) of students in Mathematics IV. The purpose of this study is to determine the differences in SRS between students who get a contextual approach with a metacognitive strategy (PKM), contextual approach (PKT), and conventional approach (PKV). This research is an experiment. The subjects in this study were students of Civil Engineering STT Garut semester 4 of 2018 which consisted of three classes (groups). The experimental group-1 was given PKM, the experimental group-2 was given PKT, and the control group was given PKV. The instrument used was a SRS scale based on a Likert scale. Data analysis was performed with ANOVA test. The main results of this study are students who get PKM and PKT significantly better SRS than students who study with PKV. Based on these results, the researcher proposes: (1) the PKM and PKT approaches should continue to be developed and used as an alternative choice for lecturers in Mathematics IV daily lectures and (2) the application of the PKM and PKT approaches becomes input material for policy makers to develop intelligence potential college student.

This study analyzed problem solving abilities of the students on mathematical differential. Descriptive qualitative applied in this study with 26 students of secondary school; 16 males and 11 females. Data analysis reveals the ability of students' problem solving abilities, namely understanding the problem, drawing up a problem solving plan, implementing the solution and re-checking the solution. The instruments used were test and interview. The findings showed that more than 50% mistake happened on drawing up a problem solving plan and re-checking the solution. So that to reduce the mistake we as lecturer should train the students in mathematical problem solving strategies.

This research aims to develop mathematics education comics through digital android. This type of research is a combined RND research from Brog and Gall and MPI. The product was developed through several stages by manually designing, scanning, providing colour with photoshop, giving text balloons after that the process of digitizing android is done using PowerPoint, Ispring and Web2APK which can be operated through android, gadgets offline and online. The evaluation of this product was assessed by several experts namely experts in language, material, graphic design and colleagues. Data collection techniques using a questionnaire and then analyzed descriptively quantitative. The results of the assessment of experts get good criteria from several expert validators, language, material, and graphic design conclude that this product is feasible to use.

Financial Service Authority (FSA) introduced a new policy on Sustainable Finance to financial institutions such as Banks. It is currently a hot issue that needs to be implemented in the selection process of potential debtors. Consequently, the credit rating system needs to be renewed. Statistical methods can help to include permits and environmental impact in the selection process. Thus, this study intends to formulate a credit rating model for productive debtors. This study used a quantitative method using Multivariate Adaptive Regression Splines (MARS). Our study's significant finding is that the credit rating model for productive debtors that have been formulated has type I error of 0.00% and type II error of 0.54%. Furthermore, the authors believe that this model can be used to asses potential debtors' credit rating while adhering to the policy of Sustainable Finance.

Control diagrams are graphical communication media that can be used as tools in the process of controlling statistics statistically to assist in monitoring and improving a quality process by helping to separate specific cause and general cause variables. Basically the control diagram plots the area of acceptance of a hypothesis test. This study aims to detect disruptive causes in the control diagram in time series cases and to justify the statistical model in accordance with the procedure. A process is said to be controlled if the observational data from that process behaves like random iid variables (independent identically distributed), and if it is not controlled, it is out of control. The study uses 25 days' time series observational data in PT. Guccitex Cimahi. In this time frame analysis, research that is influenced by specific causes can be treated as outliers of the time series model and can be detected by outlier detection methods. The results in this study explain that a traditional control diagram is very dependent on the assumption of iid (independent identically distributed). Application in real life faces observations that are not iid (independent identically distributed), which show the effects of trends, seasonality, and other influences. The control diagram is in principle the same, using time series analysis to overcome these effects by plotting the area of acceptance of a hypothesis test, but if the process is not controlled, the control diagram cannot provide any guidance, so it is necessary to do a data analysis using analysis time series.

The outbreak of novel coronavirus at the end of 2019 (covid-19) has become a global concern due to its fast transmission from human-to-human. It is first time discovered in Wuhan, Hubei Province in China. In this research, the author tries to construct epidemiological model that consist of six subpopulations such as susceptible (S), exposed (E), infected (I), isolated (Q), recovered (R), and dead (D) population. Those compartments will be analyzed to get basic reproduction number (R₀). The data used in this research is secondary data that obtained from the recent study and various news report related to the covid-19 outbreak. Fitting method will be carried out to describe the virus outbreak and see the trend of the future condition based on the real observation data and the mathematical function that has been determined. The expected result of this research is that the mathematical fitting model and its analysis helping the epidemiologist and health practitioner to determine the right treatment to stop the outbreak so that the society could be back to virgin population.

The purpose of this study is to analyze the use of geogebra applications in mathematics learning on quadratic function material. In addition, it needs to be seen how respondents' conceptual and procedural understanding of the quadratic function material. This research uses quasi-experimental by taking a sample of 80 respondents. Samples were given treatment with the use of geogebra applications in mathematics learning with quadratic function material. Data analysis was performed using SPSS. The results showed that the use of geogebraic applications was effective in developing respondents' conceptual and procedural understanding of quadratic function material.

Let R be commutative algebra with unit element. Given any R -modules M and N, and any nonzero submodule U of M, Mahatma and Muchtadi-Alamsyah defined the k -th U -extension module of N by M for every positive integer k. Further, Mahatma showed that given any short exact sequence of R -modules and R -module homomorphisms, there exists an exact sequence of U -extension modules of N by M. It is just that the sequence consists of only limited number of nonzero modules. In this paper we investigate the conditions needed by the sequence so that it can be extended into a longer one.

The Generalized linear mixed model (GLMM) is an extension of the generalized linear model by adding random effects to linear predictors to accommodate clustered or over dispersion. Severe computational problems in the GLMM modelling cause its use restricted for only a few predictors. When many predictors are available, the estimators become very unstable. Therefore, the procedure for selecting relevant variables is essential in modelling. The use of penalty techniques for selecting variables in mixed models is still rarely applied. In this article, the penalized Lasso approach proposed to handle these kinds of problems. The proposed methods select variables and estimate coefficients simultaneously in GLMM. Based on the Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), and standard error criteria, it was found that glmmLasso has a better performance than GLMM. For the factors affecting Indonesian's student scores, where glmmLasso produces three significant covariates for the GLMM model while GLMM without penalized Lasso has five covariates, which means that the GLMM model is more complicated than glmmLasso. Gender, school quality based on National Examination (UN) scores and the opportunity for students to investigate to test their ideas are essential covariates as factors that influence the rating of Indonesian students.

Growth in household activities that increase water resource needs can be incompatible and their availability can be threatened. Limited water supply makes groundwater a primary need because it is easily exploited and practical. This paper attempts to understand the behavior of shallow groundwater saving by households and to observe the influence between knowledge, attitudes, and practice with their behavior. This research was conducted in the Bukit Raya Subdistrict in Pekanbaru City with 113 respondents, analyzed using a quantitative approach (SPSS). The results showed that knowledge, attitudes, and practice had a positive influence of 32.4% on shallow groundwater saving behavior. This research concludes that knowledge is the most influencing shallow groundwater saving behavior seen from the influence of attitude and practice.

Smoking is one of the health problems in Indonesia. Many factors cause a person to smoke, both originating from oneself and the environment. The statistical question that arises is how to choose the factors that are most significant in influencing people to smoke. These factors are the variables that will sed in modeling. This study aims to select the variables in the compressed linear mixed model using the Lasso penalty and the Boosting function, using the EM and REML algorithms. Respondents in this study were 160 smokers in Jambi Province. Based on the AIC value, the best model obtained from the selection of variables with the Boosting function and REML algorithm. The analysis shows that work, welfare level, and family members who smoke are the factors that influence people smoking in Jambi Province.

Let G be a graph with q edges. A labelling f of G is said to be root square mean labelling if f: V(G)UE(G)→{1,2,...,q+1} such that when each edge e = uv labelled with f(e)=[f(u)²+f(v)²/2] or f(e)=[f(u)²+f(v)²/2] then the resulting edge labels are distinct. A graph G is called a root square mean graph if G can be labelled by a root square mean labelling. In this paper we determine a root mean square labelling of two graphs obtained from path, which are corona product of ladder and complete graph with order 1, and a graph obtained from triangular snake by join one vertex with degree 2 in each triangle to a new vertex. The method of labelling construction is we need to do labeling to the vertices of the graph with label 1, 2, 3, ..., q+1. The labels of the vertices are not necessarily different. The next step is we need to do labeling to the edges with the certain formula by using the vertex labeling. The edge labels must be different. By the labelling we construct, we proof that the two graphs are root square mean graphs.

The purpose of this study was to see the development of students' mathematical communication skills between those who obtained the ELPSA learning model assisted by GeoGebra and those who obtained the conventional learning model (direct-instruction). This study uses a quasi-experimental method. The results showed that the achievement and improvement of mathematical communication skills of students who obtained the ELPSA learning model assisted by GeoGebra better than those who obtained the direct-instruction model. The GeoGebra-assisted ELPSA learning model can be used as an alternative in developing mathematical communication skills, especially in the transformation geometry material in secondary schools.

Let R be commutative algebra with unit element. Given any R-module U, there exists a category C_U whose objects are all pairs (N,M) where N is direct sum of U and M contains U. It has been shown that if W is a direct summand of U then there exists a functor from C_U to C_W. Further, if W and U are isomorphic then there exists category equivalence between C_U and C _W.

In this paper we represent an algorithm for finding the interval solution using gradient vector. This algorithm applies the optimization problem based on gradient vector in order to obtain the lower bound and upper bound of the interval solution. In this method, initial solution has been used with stopping criteria to compute the solution. An example problem is solved to represent this method with μ=0.5, μ=0.1, μ=0.05, and μ=0.01. By this method, we obtain optimal numerical solutions results with μ=0.01.

The properties of Max Plus Algebra can be applied to the matrix. Furthermore, the generalized inverses in a matrix can also be related to this algebra. This paper discusses some properties of these concepts on 2 x 2 matrices integers modulo 3. Here, we derive the properties of matrices in this algebra. Then, the generalized inverses in these matrices is formed. We conclude that there is some relation between the matrices and its generalized inverses. Some examples of matrices are given to illustrate the properties.

The increasing number of disasters in Indonesia exerts significant economic loss and human casualties, whereas Indonesia has focused on disaster risk reduction. Recent studies are lacking to explore how economic growth influences the impact of disasters. This paper aims to seek a deeper understanding of how welfare that represented by the human development index influences the impact of disaster on the people. We implement the concept of welfare and risk reduction as an approach to analyze disaster and welfare data with a focus on flood events in 2008-2018. We obtained the data from BNPB and Statistics Indonesia. We fitted a multivariable negative binomial regression with 'human losses from deaths' as the outcome and provincial Human Development Index (HDI) and provincial gross domestic product (GDP). The results suggest that Provincial HDI is negatively significant associated with human losses from deaths. However, GDP was also found to be positively significant associated, albeit less strongly, with human losses from deaths. These associations bring about potentially significant policy implications.

Inflation in Indonesia, in general, can be caused by a combination of various factors, both in terms of demand, supply, and expectations. The contribution of each element that influences inflation is not always the same from time to time. Gordon (1997) explains the determinants of inflation from these three sides, namely demand, supply, and expectations. The importance of expectations in influencing increase was also stated earlier by Chopra (1985). In this study, spatial Durbin for panel data with fixed effects in modeling inflation in the West Java province. The results show that Minimum Work Wage, percentage of poor population, Gross Regional Domestic Product (GRDP), spatial lag of poor population, and spatial lag of GRDP have a significant influence on the Durbins panel spatial model. There is an adjacent regional effect on inflation in the West Java province based on the value of the lambda obtained. Based on the criteria R-square of 94.29%, it can be concluded that the SDM panel data model has an excellent performance in explaining the diversity of data. The AIC and BIC criteria also show that the SDM panel data model well applied in modeling Regency/City inflation in West Java province.

Land and forest fires in Indonesia have a long history. Several major land and forest fires in Indonesia such as in 2002, 2006, 2009, 2015, and 2019 were associated impacts of the ENSO and IOD phenomena. This research aims to find out how much ENSO and IOD impact to land and forest fires in Indonesia. This research used Sea Surface Temperature (SST) anomalies in the Nino 3.4 index region and DMI region as indicators for ENSO and IOD, while hotspot was used as an indicator of land and forest fires in Indonesia. Heterogeneous Correlation Map (HCM) was used to describe the correlation of hotspots with ENSO variance and IOD variance on spatial patterns. The HCM obtained from Singular Value Decomposition (SVD) analysis used to identify the variances. The result showed that anomalies SST in Nino 3.4 index region had greater correlation with hotspot in Provinces of South Kalimantan, East Kalimantan, and Central Kalimantan than those of other regions in Indonesia. Anomalies SST in DMI region had greater correlation with hotspot in Provinces of Lampung, South Sumatera, West Kalimantan, South Kalimantan and Central Kalimantan, than those of other regions in Indonesia. Temporal analysis showed that the largest variance of hotspot in Indonesia mostly in the mid of the year.

Analysis of students' critical thinking skills is the focus of this study. The material used in this research is Newton's law. This research was conducted in one of the senior high schools in Malang City. The research was carried out using the critical thinking test method to measure students' critical thinking skills, with the collection taken was class X IPA with a sample of sixty-four students who were divided into experimental and control classes. The experimental class was applied the ABSI model while the control class was applied to the conventional model. The learning process in the classroom, especially in physics lessons, has not used a learning model that can improve students' critical thinking skills, namely still using discussion, question and answer and lecture models, this also causes less open opportunities for students to participate in learning and low student curiosity so that impact on students' critical thinking skills. By using the ABSI model and tests of critical thinking skills in seeing students 'critical thinking skills in Newton's law material, the result is that in the class with ABSI model learning, students' critical thinking abilities are higher than those with conventional models.

The thermoacoustic travelling wave device system has been designed and we have tested, this thermoacoustic device consists of loud-speakers as a sound wave source with a capacity of 120 W, branched-tubes resonator, and loop-tube resonator that have a regenerator with a length of 8 cm placed inside loop-tube. Regenerator is made of acrylic material which has a size of 1 mm and the distance between pores and other pores also has a distance of 1 mm. The performance of the thermoacoustic travelling wave device is observed from the temperature changes it has and is reflected in how much changes in cold reservoir temperature and hot reservoirs it can achieve. The results of the experiments obtained will be analyzed in the form of temperature charts showing temperatures in hot reservoir and cold reservoir as a function of time. The temperature difference between the two sides of the regenerator reaches 26,3°C with details of the temperature rise of the heat side of the regenerator (T_h) up to δT_h = 13,4°C and the temperature drop of the cold side of the regenerator (T_c) down to δT_c = 12,9°C.

This study aims to describe the mastery of HOTS of prospective physics teachers in digital electronics courses after implementing game-based learning. The type of research is a quantitative descriptive study. The number of research subjects consisted of 50 students. Data were collected using a test of learning outcomes about digital circuits in the cognitive domains. The data were analyzed to categorize the students' high-level thinking skills. The data processed were displayed in the form of diagrams and graphs. The data were also equipped with a student response questionnaire. The results of the analysis showed that 46% of the HOTS in students were categorized in "good" category; 28% in "very good" category; a small proportion of others were categorised as "quite good" and "less good". The HOTS of prospective physics teachers was already sufficient with an average of 70.25. Student responses were deemed in the "good" category. Therefore, it can be concluded that the mastery of HOTS in prospective physics teachers in digital electronics courses after implementing game-based learning is categorized as high. Thus, it is concluded that the mastery of HOTS in prospective physics teacher candidates in digital electronics courses can be further enhanced and trained by applying game-based learning.

This study aims to investigate comprehension shifting students of distance and displacement concept on learning process. A mixed methods approach using embedded experiments has been used to analyze the comprehension shifting of students. Quantitative and qualitative data obtained from responses to multiple-choice conceptual questions and the reasons put forward during the discussion in the learning process. The results of the analysis have shown that initially all students were not able to distinguish distances and displacements correctly. After the initial verbal discussion, about 10% of students were able to correctly distinguish distance and displacement. The discussion was continued with lecturer intervention by asking students to visualize the problem through pictures or graphics, so that all students (100%) were able to distinguish distances and displacements correctly. Furthermore, the results of the analysis of changes in student understanding can be used as a basis for educators to design learning strategies for the topics of distance and displacement in particular and kinematics in general.

This research aims to produce senior high school physics module based on STEM Problem Based Learning on Newton's Motion Law Material that is valid and practical. This is a development research using a design model of ADDIE that modified with Tessmer's formative evaluation method. Tessmer's formative evaluation stages in this study include self evaluation, expert review, one-to-one and small groups. Data were collected through interviews, expert testing and questionnaires at the expert review stage. The one-to-one and small group stages and field tests were conducted at SHS Number 1 Banyuasin, South Sumatra. The results of the expert review stage obtained the final score of material validation 1 (very feasible or very valid), design validation 0.91 (very feasible or very valid) and language validation 0.95 (very feasible or very valid). Based on the results showed this research produced senior high school module based on STEM Problem Based Learning on Newton's Motion Law Material. It is recommended that this module can be used as an alternative teaching for Newton's motion law material.

The accretion process occurs when neutron stars are in a binary system. The hypothesis says that accretion reduces the magnetic field in a neutron star. The correlation between accretion and decrease in the magnetic field is indicated by the magnitude of the magnetic field dynamics and the mass accretion rate. The purpose of this research is to formulate the mass rate of accretion in rapidly rotating neutron stars. The accretion disc is assumed to be at the equator. The method used is theoretical-mathematical analysis. The quantities to be summarized are the Killing vector, 4-vector velocity, the angular velocity, and the Lorentz gamma factor derived from the metric. The metric used is a rapidly rotating neutron star. The rate of mass accretion is calculated from these quantities and the equation for mass sustainability. The equation of mass accretion rate is derived from these variables and the mass conservation equation. The equation of mass accretion rate is affected by the radial velocity of accretion flows and distance between matter and center of a neutron star. The result obtained is covariant with the equation of mass accretion rate for Kerr black holes. The results obtained can provide a dynamic equation for the magnetic field to produce an equation for the decrease in the magnetic field in a rapidly rotating neutron star.

Misconception is something that causes students fail to understand physics concept intensively. The research aims to identify the students' misconception on Newton Law concept using four-tier diagnostic test. Method used in the research was descriptive method. Data of students' misconception was collected using test and interview. The subjects of the research were students of X MIPA 5 in State Senior High 10 Malang in 2019/2020 academic year and they were 32 students. The result of the research shows that the level of students' misconception of X MIPA 5 in State Senior High 10 Malang is 54% which belongs to medium category. The research found that the misconception which happened to most students was on Newton II Law which is 63%. It also relevead that misconception in students occur because of experiences or events experiences by students in everuday life, students' initial concepts and teachear teaching methods.

Passively Q-switched erbium-doped fiber laser (EDFL) have been demonstrated using graphene oxide (GO) film as saturable absorber (SA). The aim of this experiment is to generate and demonstrate passively Q-Switched Erbium-doped fiber laser (EDFL) using GO as a saturable absorber. Stable Q-switched operation can be achieved at 1558.8 nm. By increasing the pump power from 26.32mW to 71.65mW, the repetition rate also increased from 30.58 kHz to 51.81k Hz. The pulse width of the laser were 11.2 – 4.73 µs. The maximum output power and maximum peak power obtained are 128 µW and 521.98 µW respectively at a pump power of 71.65 mW. The pulse energy reaches 2.47nJ. These results show that GO is a new potential SA material for pulsed laser applications.

The Covid-19 pandemic forced the Indonesian government to release learning from home policy. This policy also applies to the Physics Education of Siliwangi University. This study aims to know undergraduate students' perceptions of online learning during the transition period from face-to-face learning to online learning in Physics context. Undergraduate students' perceptions of online learning are seen from aspects of access to technology, technology for learning, online learning readiness, and attitude towards digital technology literacy. The data is collected by an online survey method. This research shows that most undergraduate students have sufficient facilities for online learning and have a positive attitude towards digital technology literacy. Another finding from the study is that the majority of undergraduate students have difficulty accessing the fast internet (83.87%). Undergraduate students like a combination of online media learning and offline media learning (90.32%), but they do not like full online learning (98.06%). This research indicates that teachers should support students at online learning by providing proper Physics learning material and media. This research is expected to suggest better online learning and literacy technology in Physics context in the new normal era.

This study was to see how to optimize the application and laboratory software on Oscillation and Wave material. This study was conducted using computers and android equipped with Internet access in SAMR framework. SAMR is a framework that requires the use of technology in learning The design of this research is content analysis. The results show that the Olabs application is complete and the most capable of explaining the formula if it is reviewed mathematically and physis meaning. This application is also able to explain the oscillator and wave phenomena well. Based on this research, during the Covid-19 pandemic, students can do STEM (science, technology, engineering and mathematics) from home, one of which is with the help of the Olabs and PhET application.

This study aimed to evaluate the physiological responses of the Holstein Friesian (HF) dairy cows raised under tropical conditions in Indonesia. Twenty-one dry-pregnant cows, approximately 7–8 months of pregnancy, 1-3 of lactation, 500-600 kg of body weight and 3-5 of body condition score were used for that purpose. The cows were fed twice daily in the form of total mixed ration (TMR) and given add libitum amounts of drinking water. Ambient temperature, relative humidity and temperature humidity index (THI) were recorded. Physiological responses i.e. rectal temperature (RT), pulse rate (PR) and respiration rate (RR) and heat tolerance coefficient (HTC) were also recorded. Descriptive statistics such as mean and standard deviation were performed using SPSS software. The results showed that both ambient temperature and THI reached their maximum (26.5±1.520C and 77.1±2.21, respectively) at 01:00 PM and minimum (22.6±0.510C and 71.8±0.90, respectively) at 3:00 AM. Contrarily, the relative humidity was highest (88.9±1.56%) at 03:00 AM and lowest (78.8±2.49) at 01:00 AM. The physiological responses (RT, PR and RR) and HTC increased in line with the increasing ambient temperature and THI. In conclusion, all of the HF cows are exposed to mild stress due to increasing ambient temperature and relative humidity.

This study aims to identify learning content of low carbon at elementary school level in Indonesia. The method employed in this study was a combination between systematic literature review and content analysis. The results showed that low carbon content at elementary schools was mapped and presented in a simple structure so that the substantial aspects of the learning was easier to understand by the elementary school students. It has also been proven that low carbon learning content was beneficial to develop in learning within elementary school context as it trained the students to get used to living in low carbon since early ages.

The purpose of this research is to perform modeling and simulation to solve differential equations in cases of physical phenomena. The physical system studied is simple harmonic motion. The method used is the method of problem solving using computer software. The simulation uses the Matlab program by applying the Euler method. The result obtained is to distinguish the oscillator graph without any external forces with any forces. This solution helps students solve problems using computer software in giving physical meaning. Therefore, students must be trained and guided to have the ability to think to make it easier to solve problems with the help of computers.

This research and development aim to describe the characteristics, determine the feasibility, and determine the Scientific Literacy-based physics learning module's effectiveness on direct current circuit material. The development procedure uses the Research and Development model by Thiagarajan with 4-D stages (define, design, develop, and disseminate). The subjects of this study were students of class XII at SMA Negeri 1 Jogorogo Ngawi. Data collection techniques using observation, interviews, and questionnaires. Data analysis was carried out quantitatively and descriptively qualitatively. The results of the research and development concluded that 1) a physics learning module based on Scientific Literacy on direct current circuit material was developed based on the Scientific Literacy component, namely a) the scientific process includes explaining scientific phenomena, using scientific evidence, identifying scientific questions, b) scientific content includes understanding phenomena, and c) the context of science includes solving problems in everyday life; 2) the Module is feasible to use in physics learning in an excellent category, the average percentage of validation results is a) material components: 91.46% b) media components 92.99% c) scientific literacy components 93.75%; and 3) a useful module for improving critical thinking skills including Interpretation, analysis, evaluation, inference, explanation, and self-regulation with an increase of 17.56%.

A thermoacoustic refrigerator is a capable device to produce temperature differences with acoustic work (sound waves) as the source. The advantage of these machines is that the working gas medium used is air, so it doesn't produce much pollution and of course, it is environmentally friendly. This paper describes the measurement of stack length variations ranging from 4 cm to 7 cm on the performance of the standing wave thermoacoustic refrigerator. This study aimed to find the optimum stack length in a thermoacoustic machine with a resonator pipe length of 80 cm. Operation time is carried out for 30 minutes. The main components of a thermoacoustic device consist of a regenerator, resonator pipe, and a loudspeaker. The regenerator has a big role, namely as a place for energy conversion to occur. The results obtained are a temperature decrease, a temperature increase, and a temperature difference. The results showed that the temperature decrease and the temperature difference on the stack length of 7 cm were the decrease in temperature and the maximum temperature difference with the results of 4.6°C and 9.3°C, respectively. Therefore a standing wave thermoacoustic refrigerator with various lengths of the stack has been experimentally studied.

The problem of food waste is increasing as food needs increase as a source of human protein. Therefore, biogas conversion can also answer the problem of household food waste treatment. The purpose of this study is to find out the producing of biogas from a mixture of food waste and liquid waste tofu in anaerobic biodegester at thermophylic temperature. The manufacture of biogas in this study using batch feeding, which is a type of digester that replenishes organic matter is done once full and then waited until biogas is produced. The manufacture of biogas is carried out for 5 weeks. The observed parameters are COD, BOD, TS, VS, and the resulting volume of biogas. From the observations obtained that, by varying substrate can decrease COD, BOD, TS, while substrate temperature can increase VS. The volume of biogas produced in the mixture of liquid waste tofu 60% and food waste 30% is 22.600 ml. The results showed that the percentage of substrate from the mixture of food waste with liquid waste tofu had an effect on increasing biogas production.

The role of fungus Basidiomycota can be used as an indicator of wisdom and the level of maturity forest ecosystems, both as decomposers, symbionts, and pathogens. The existence of several species of edible mushrooms is also used by local communities as food and medicine. This study aims to identify the diversity of fungus species in Central Kalimantan's open forests, as part of ethnomicological information. The method used was the purposive sampling technique. The results showed 3,715 fruiting bodies of mushroom from 120 species and 41 genera were found at the study site with moderate levels of biodiversity (R '= 3.51; H' = 2.14; D '=0.68). Based on the study of ethnomicology information obtained 5 species of edible mushrooms that are commonly consumed by local communities, such as, cloud ear fungus (Auricularia polytricha), Oyster Mushroom (Pleurotus ostreatus), Hygrocybeal calc, Cantharellos, and Common Puffball (Lycoperdon pertatum). For the type of fungus that is used as an ingredient for disease treatment, 2 types are found, namely polyporus cinnabarius, and ganoderma. The research findings found that Central Kalimantan's open forest biodiversity is still quite good, with a moderate level of diversity. Besides, ethnomicology can be developed as local wisdom in Central Kalimantan.

Although the Internet of Things (IoT) application is already widely used by students, understanding the working principle of the device is not easy. This paper aims to describe the way to introduce IoT to students through the development of learning media based on Arduino Uno built-in Wifi on temperature and wind speed monitoring devices. The method used is Research and Development. The results showed a flow chart and design of tool development. After the product is made, an expert's view of the visibility and function of the device as a physics learning medium is needed before the invention is applied for its effectiveness to be known.

Optical instruments are one of the basic subjects in physics. The use of a very wide range of optical instruments in life creates a demanding environment so that students have adequate skills. This research aims to develop worksheets that can support student skills. The worksheet prepared in the form of a learning tutorial is expected to improve higher-order thinking skills. This study uses a 4D development model (Define, Design, Development, Dissemination) with the stages of implementation to Development. The results showed that there was a significant increase in students" higher-order thinking skills. The student also stated that the worksheets developed had an attraction with a percentage of 79.6% for the implementation aspect, 74.2% for the language aspect, 82.1% for the design aspect, and 75.3% for the acceptance aspect.

Utilization of modern technology has been widely felt by the public as well as utilizing wireless charging technology on android phones. The charging, of course, uses the concept of Tesla coil, namely the transfer of electricity without wires. The Tesla coil can emit electromagnetic radiation which depends on its input. This study aims to design a miniature tesla coil as a magnetic inductor. In this design, measuring electromagnetic radiation with a coil diameter of 0.3 mm, 0.4 mm and 0.5 mm with the same number of turns is 500 turns. The method used is an experimental method using determinants such as the diameter of the coil, the height of the measurement of electromagnetic radiation, and the distance measurement of electromagnetic radiation. Experiments carried out varying independent variables including diameter of the coil, measurement distance, height and number of turns as a constant quantity. The measurement uses the electromagnetic radiation detector DT-1130 to measure the electromagnetic radiation at several heights of the Tesla coil. The results showed that electromagnetic radiation which has the highest value is at the top or at the end of the coil for the position near the primary coil obtained the lowest electromagnetic radiation results among the three measurements, whereas for distance researchers get the result that the further measurement between the electromagnetic sensor and the Tesla coil electromagnetic radiation is getting weaker. At a winding diameter of 0.3 mm which produces the smallest radiation but when brought closer to the Neon lamp the light intensity of the Neon lamp is brighter compared to the diameter of the winding 0.5 mm which has the most radiation.

The development of science and technology is inseparable from the availability of hardware and software. One of its uses is teaching aids in physics practicum, especially simple harmonic motion. Digital technology can shorten the time in the implementation of practical work in the field. In this study aims to design a simple harmonic motion practicum tool using Arduino Uno based on IR resistance sensors. Data was collected using a small angle of 10° with variations in the number of waves and time obtained. The results will be displayed on the LCD. This study also compares the results of recording digitally and manually. Based on the data obtained, the results of digital experiments are more accurate than the results of manual experiments with an accuracy of 96.69% and digital SHM device experiments also show precise results. So that digital SHM tools can be performed on physics experiments in simple harmonic motion material.

The aim of this study was to determine the feasibility of automatic time-lapse-based Atwood aircraft tools to explain Newton's second law. The method in this research was the experimental method. Instrument testing was carried out at mass loads m₁ of 0.01 kg, 0.02 kg, 0.03 kg, by using weights m₂ of 0.1 kg at a distance 60 cm and force variations of 0,5 N, 0,6 N and 1 N. The results of the measurement and analysis of the data obtained acceleration in theory Newton's second law, namely each for mass variants and successive forces is 4.864 m/s², 4.102 m/s², 3.414 m/s², 2.069 m/s², 2.581 m/s² and 4.102 m/s². The results of the acceleration calculation are based on an automatic time interval 4.220 m/s², 3.826 m/s², 2.985 m/s², 1.697 m/s², 2.415 m/s² and 3.826 m/s². The smallest error data is 6.39% and the biggest error is 18%. The results of these measurements indicate the measurement is still accurate because the error percentage is less than 20%.

The need for coal is increasing every year so that coal exploration activities need to be done to maintain the availability of these materials. Exploration activities generally use the correlation of geological method (analysis) and direct measurement using the geophysical method. One of the geophysical methods used is the downhole seismic method, to determine the quality of coal hardness through several seismic parameters, namely variations in the value of the initial wave velocity (Vp & Vs) and the wave travel time (Tp & Ts). This study aims to avoid mining land clearing and environmental destruction that are misplaced. This exploration activity is carried out at six measurement points. The results showed that the density of coal in the range 1.42 - 2.05 g/cm³, while coal that is feasible to be mined has a density of 1.81 - 2.05 g/cm³ with very soft rock to very hard rock classification.

This study aims to develop a harmonic oscillation e-module based on pbl for helping hots improvement of senior high school students at SMA N 23 Jakarta. The ADDIE Model of research and development was applied in developing such e-module prior to measure improvement of students' hots. The validation results of experts indicated the values of 78.1%, 77.7% and 93.8% for media, learning model and content, respectively. The trial result of teachers and a small and big groups of students respectively indicated an average score of 93.95% and 95.1% and 86.5% for all aspects of content eligibility, presentation, language and graphical eligibilities. Furthermore, The t_gain test calculation shown that the t_gain count (2.58) was bigger than t_gain table (1.67) with 5% significance level. The analyzed result indicated that the improvement of hots of students which was taught with the pbl based e-module was better than those who utilized the non pbl based e-module of the harmonic oscillation. Whiles, the result of d'Cohen test indicated that the developed e-module was very decent to be utilized as learning media with contribution category of medium (based on d'Cohen test result of 0.64) for improving hots of senior high school students.

Efficiency is one of the important things to consider when choosing household appliances, especially cooking equipment. Currently the community is starting to switch from from liquefied petroleum gas-based cookers to electric cookers. Therefore analysis is needed to determine the selection of electric cookers that are efficient in accordance with consumer needs. To accomplish this study, testing with boiling water was carried out on three types of electric cookers namely induction cooker, halogen and electric coil. This test is carried out to obtain input and output energy from each stove so that efficiency can be obtained. From the test results, it has been found that the induction cooker has the highest efficiency among the electric cooker.

The STEM Project is a learning model that can be used by lecturers in the learning process so that students can get used to analyzing and synthesizing, to come up with an idea that can develop the competence and science literacy abilities of elementary school teacher candidates in the framework of learning in the 21st century. The study aims to improve the ability of the science literacy of Pre-service elementary school teachers by using the STEM Project Learning Model. This study was conducted on Pre-service elementary school teachers as elementary school teacher education students at the University of Halu Oleo Kendari. The results obtained indicate that the science literacy ability of Pre-service elementary school teachers has increased significantly. The increase is based on the results of statistical analysis which shows a significant increase in the ability of the science literacy of Pre-service elementary school teachers, after participating in learning using the STEM Project model. For this reason, the use of the STEM Project model in learning science enables prospective teachers to become accustomed to conducting comprehensive analyzes of problems and their solutions.

The purpose of this study is to diagnose student concepts in environmental physics courses. This study has used a mixed method. Data has been obtained from interviews, observations, questionnaires, and tests. Study subjects were 78 physics education students who had passed environmental physics courses and 4 lecturers. The results of the study have shown that the chapter in the bad category is the chapter "External factors that influence life on earth". This answered with the percentage of students who answered correctly there were 44.8. And the chapter "Association of physical principles with soil characteristics" is also in the bad category with a percentage of 46.2. This study has been able to provide a description of the material content that is not understood by students in experimental physics subjects, especially related to the concept of physics.

Musi River in the upstream and estuary is used for fisheries, transportation, industry, and settlement. These activities has potential to produce plastic waste with various types and sizes, one of them is macroplastic (2.5-100 cm). This study aims to determine the distribution and abundance of macroplastic in the upstream and estuary of the Musi River. This study used a purposive sampling method with 6 stations, 2 stations in the upstream and 4 stations in the estuary. Macroplastic sampling used transect quadrants then sample is cleaned and dried, counted, identified and weighed for each type. And for macroplastic coverage by taking photos of each transect quadrant, then calculate the percent of coverage using the Point Intercept Transect (PIT) method. The results of this study indicate that the macroplastic abundance in the upstream and estuary of the Musi River ranges from 5-32 items/m² with an average weight of 27.82 – 126.89 gr/m². Macroplastic types are dominated by plastics fragments, food wrappers, other jugs/containers, bags/films, and cups, while macroplastic coverage is dominated by bags/films.

Education systems in various countries have experienced massive transformation since the development of information technology. The learning environment has shifted from face to face learning to web-based education or e-learning. There are multiple free online learning platforms available on the internet, one of which is Moodle. The main aim of this study is to develop physics learning media with Moodle to improve student's motivation in learning physics. The ADDIE model framework is used to create web-based physics learning media, which consists of four stages, namely analysis, design, develop, implement, and evaluation. The product was validated by material and media experts, as well as two physics teachers as practitioners. The validation and practicality test results show that the web-based learning media is valid and practical as teaching media to improve student's motivation in learning physics. The results of the effectiveness test using the design of one class pre-test and post-test showed an increase in students' motivation with an N-gain value of 0.80 with categories high. The results of this study give insight for physics teachers on how to design technology-based learning to increase student motivation in learning physics.

The difficulty of students in understanding concepts in physics has a significant effect on students' motivation. The purpose of this study is to develop animation media that make students easier to understand the abstract concept of Newton's law and find out students' responses to the use of instructional media. The 4D framework is used to develop animation-based learning media, which consists of four-phase, namely: define, design, develop, and disseminate. The instruments used are a questionnaire and interviews. The results showed that (1) Based on expert judgment Animation-based learning media was appropriate and feasible to be implemented in the physics class; (2) used of media animation in learning physics could facilitate students in understanding the abstract concept of Newton's Law, especially in describing the direction of the force and gave opportunity to the student's to increase their motivation to learning physics where average score of the motivation was 70% in the "High" category.

Physics consists of concepts that are macroscopic and microscopic, physics concepts that are microscopic or Physics concepts that are invisible or unobservable. If the phenomenon that is microscopic can be understood then the macroscopic phenomenon will also be easy to understand. This research aims to produce a Massive Open Online Simulation (MOOS) online course on microscopic concepts that enhances creative thinking. The research method used was Embedded Experiment Design with research subjects being 60 high school students at one campus in the province of Jakarta, Indonesia. The results showed MOOS of Physics Concepts Microscopic for Improving Creative Thinking with average normalized gain score <g> creative thinking increased by 0.54 with the medium category. These results indicate that MOOS on microscopic concepts increases students' creative thinking.

This paper presents the development and characterization of the natural iron sand as a microwave absorber. To develop a new microwave absorbing paints in the 7–13 GHz range, the iron sand sample was prepared through the mechanical milling process and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), Permagraph and vector network analyzer (VNA). The reflection loss (RL) was calculated and simulated for different thicknesses of the material using the complex permittivity and permeability and found the broadband characteristics with minimum absorption. The results indicated that the natural iron sand is beneficial as potential candidates for military applications.

In this paper, the barium hexaferrite was successfully prepared by a conventional ceramic method and the precursors of BaCO3 and natural iron sand from Puger Beach, Jawa Timur-Indonesia. To develop a microwave absorbing material, the complex permeability, permittivity, and microwave absorption ability were investigated using a vector network analyzer (VNA) in the frequency range of 8.2-12.4 GHz. The results showed that barium hexaferrite presented an excellent broadband absorption (>90%, RL <-10dB) and a suitable absorber with high broad bandwidth and attenuation in the microwave frequency range.

An smartphone application which are used as learning material on the subject of temperature and heat have been developed. The development process is carried out using research and development methods with reference to the Analysis-Design-Development-Development-Implementation-Evaluation development model. The novelty of learning material that was developed was to use inquiry-based learning in the writing system. In addition, the learning material which developed also includes questions that refer to higher-order thinking. The results of the validity tests show the adequacy of the learning materials with the level of difficulty of the learning materials in high school. The learning material has been tested in SMA 16 Jakarta. The test results show an increase in learning outcomes shown by the gain score of 0.4.

Granular simulations have been carried out to visualize attached to porous vertical surfaces. We simulate the optimal ratio of dry surfaces. This simulation uses the uFlex particle with three pore sizes. The movement particle using parabolic motion with the initial horizontal speed only. The simulation results show that for uniform particle velocities, the number of particles that are attached depends on the size of the particle sphere itself. These results can combine with the previous study to use in future research.

The simulation of physical phenomena between fluid and its boundary is a fascinating study because of its application in various fields of engineering. In this simulation, we analyze how fluids are arranged as granular particles with certain conditions interacting with the wall. The walls are varied as the characters that represent the shape of the breakwater building. This simulation compares the effectiveness of commonly used wave barriers. Wave barriers are used to hold the waves from reaching the land. In this, the simulation used two types of wave holders in the form of tetrapod and cubic, which are placed on a sloping surface. Next, an analysis of the farthest distances from the variations in the speed of the waves and the types of waves holds. Simulation results show that tetrapods are able to withstand wave speeds better than cubic.

This research is pure research in the field of pure physics. The background of the research that I did there was doing pure research in the field of physics. The subject of this research is to use the e/m measurement tool. This study aims to (1) study the influence of the magnitude of the electron velocity and the magnitude of the magnetic field on the electron path, (2) determine the e/m ratio in calculations. The results showed that the magnitude of the electron path radius is directly proportional to the magnitude of the electron velocity and inversely proportional to the magnitude of the magnetic field acting on it. Meanwhile, the calculation result for fixed current is 16.84% and the fixed voltage is 14.15%, in this case the size of the electron path is directly proportional to the magnitude of the speed of the electron path, and inversely proportional to the magnitude of the magnetic field acting on the electron.

Dynamical system of a relativistic particle under harmonic oscillator potential was considered through its stability. We first construct the Hamiltonian of the system, which represents the dynamic motion of the relativistic particle. The stability of the system was then determined by the singular point. We found that the relativistic motion under the harmonic oscillator is a stable system where the phase curve forms an ellipse.

We considered a formulation of the energy momentum tensor of scalar field containing higher-order derivatives. Starting from the Lagrangian density, we can formulate the Hamiltonian density as well as the three-component momentum density by applying the total variation on the field. We claimed that this formulation can be used to derive some nonlinear wave equation, such as the KdV equation and the Burgers equation.

We investigated the lowest state in the bilayer zigzag graphene nanoribbon by taking the electric field into account. In this calculation, we considered five collinear configurations of magnetic moment of carbon atoms at the four edges. We found that the lowest state changes as the electric field is applied. We also showed that at the high electric field, those five configurations almost become degenerate. This suggests that the lowest state is not robust to the electric field so that the electric field can control the lowest state in the bilayer zigzag graphene nanoribbon.

The classical energy of soliton of sine Gordon equation was evaluated by using the Hamiltonian density. We classify the condition at which the energy will be either convergent or divergent. For the convergent energy, we also impose the condition at which the energy is real. We justify that there is a satisfied condition to obtain real energy.

This article presents a simulation model of radioactive chain decay with augmented reality technology. Radioactive decay is classified as abstract material that is difficult to understand. This simulation will make abstract radioactive decay materials easily understood. In this article will explain the simulation changes to the 4n + 2 radioactive model by utilizing augmented reality technology. This media development uses the black-box testing method to test the accuracy and validity of the software program. Interactive media using augmented reality on radioactive decay have been able to display the U-238 chain decay model (series 4n + 2) by simulating the process of alpha and beta release in each series. This simulation successfully displayed a striking difference between alpha and beta release in the U-238 chain reaction cycle.

Simulations were performed using markerless augmented reality on the concept of Compton scattering. Compton scattering identifies that photons can not only behave as waves but also behave like particles. The process of colliding photons with electrons causes dispersion which shows that the photon has momentum. This article will explain a photon collision simulation to prove the state of light dualism by utilizing augmented reality technology. The development of this simulation was tested using the black-box testing method. Interactive media using augmented reality for Compton scattering simulations can display the concept of collisions between photons and electrons. Our simulation successfully simulates the mechanism of energy release and momentum changes before and after the contact.

We report this study that aims to know thick film sensitivity to ethanol gas. The thick film was fabricated from local mineral, is Jarosite as a source of iron oxide, and mixed with zinc oxide and Mangan oxide. The semiconductor mixture powder was synthesized by the sol-gel method, whereas the film was fabricated by a screen printing method. The film sensitivity was known with a gas sensing performance analyzer. An ethanol gas was adsorbed well by a thick film with different electrical resistance values. Due to the difference in the electrical resistance value, the thick film exhibited good sensitivity performance. The highest sensitivity was achieved approximately 91.7% of 4 gas concentration level of ethanol. Besides, the morphology of the thick film was examined by SEM that showed a pyramid-like form with a little impurity around them. The pyramid-like form looks like a spinel structure with a complex spinel-type where this structure is very well utilized for gas sensor device applications. Furthermore, these characteristics of the thick film indicated an opportunity that it can be a candidate for an ethanol gas sensor device.

This study aims to explore students' understanding of the kinematics, especially in the concepts of distance and displacement. This survey research involved 21 first-year physics students that registered in the odd semester of the 2019-2020 Physics Education Program at Universitas Kanjuruhan Malang. Justification of students' understanding of kinematics concept is done by analyzing their responses to multiple choice questions, evaluating their arguments in answering the test items, and also through a series of individual interviews. With a mixed-method approach, the data are analyzed quantitatively and simultaneously as well as qualitatively. The result shows that about 42,8% of new students 2019-2020 understanding of displacement and distance concept, and the other have shallow understandings and even misconceptions. Exploration of understanding the concepts of distance and displacement can be used as reference material and consideration for educators to develop appropriate, measurable, and efficient learning strategies.

Technology development in 4.0 industrial revolution era demands students to have 21st century skills, one of them is the skill to solve problems. The aim of the research is to describe and analyze the concept understanding and skill of physics problem solving on circular motion topic using creative problem solving (CPS) model. The research was conducted in one of State High Schools in Malang. The sample consisted of sixty eight students divided into one experiment class group and one control class group. The technique of data collecting used test of concept understanding in the form of multiple choices and test of problem solving in the form of problem analysis. The data analysis used two-ways anova. The result of the research shows that there are; concept understanding of students that are taught using CPS is higher than using Problem Solving (PS) model, (2) concept understanding of students who have high and low problem-solving skills that are taught using CPS is higher than using PS model.

Lanthanum Orthoferrite (LaFeO₃) is one of the perovskite material which has been studied as a candidate for solar cells. Perovskite doped at site-A and site B was expected to increase efficiency in its application as a solar cell. Zirconium as doping at site-B on LaFeO₃ used to reduce the size of crystals with nano size. Therefore, this research has synthesized perovskite lanthanum orthoferrite doped zirconium at site-B (LaFe_1-xZr_xO₃ with x=0.075, 0.1 and 0.15) by the sol-gel method and it has not been studied before. The precursors for these materials are lanthanum Oxide (La₂O₃), Zirconium (IV) chloride octahydrate (Cl₂H₁₂O₉Zr), iron nitrate nonahydrate (Fe (NO₃)₃.9H₂O). LaFeZrO₃ powder was characterized using X-ray diffraction (XRD) to test the crystal structure properties. The results say that the sample has an orthorhombic structure with Pnma space group. The XRD data has been refined and shows that the lattice parameters for 0.075, 0.1 and 0.15 increase with increasing zirconium concentration and crystal size of LaFeZrO₃ decreasing and showing nanosize. Nanosize crystals can maximize the absorption of dyes and it can increase the efficiency of solar cells.

This research aimed to study the feature of noise signal from various exhausts in motorcycles by the Fast Fourier Transform (FFT). The noise signal was examined into three different features; energy, entropy, and zero-crossing rate. The energy and entropy defined the noise came from an exhaust or non-exhaust, while the zero-crossing rate distinguished normal and racing-exhaust. The results showed that the energy of an exhaust noise was always in the range of 2.4 to 2.8 joule. The entropy of exhausts racing was observed in the range of 0.00 to 0.05 joule. When the acceleration pedal was on, the entropy was become higher. The zero-crossing rate of racing exhaust was in the range of 0.00 to 0.05, the non-racing exhaust was in the range 0.05 to 0.1.

Seismic refraction is one of the active seismic methods that work based on seismic waves that are refracted following the layers of the earth beneath the surface. Seismic refraction surveying is an important tool for determining the geometries and elastic wave propagation velocities of near-surface layer for oil bearing structures. Based on the data acquisition sketch obtained, the acquisition is carried out using the In-Line technique. There are two sources of vibration chosen, namely at the forward and reverse points, the distance between the 5-meter geophone and the distance between the source of the vibration and the geophone of 5 meters. The seismic data processing technique used in this study is the Generalized Reciprocal Method (GRM). This method determines the value of analysis, XY Optimum distance, time-depth analysis value, and depth. In interpreting seismic data, the calculation results that have been made are validated for accuracy using Software. From the research that has been done, it can be known as modeling subsurface structure. There are three layers, the first layer is 6 m-10m deep, while the second layer is 18m-22m deep. In the range of about 0m-20m, the first layer has a velocity of 507.74 m/s, the second layer has a velocity of 1420.43 m/s and the third layer has a velocity of 2522.30 m/s. In the range of about 20m-80m the first layer has a velocity of 550.12 m/s, the second layer has a velocity of 1575.11 m/s and the third layer has a velocity of 2607.45 m/s. In the range of about 80m-100m, the first layer has a velocity of 482.34 m/s, the second layer has a velocity of 1301.09 m/s and the third layer has a velocity of 2400.86 m/s.

Volcanic ash is dangerous for aviation because it can harm the plane engine. This study built a simulation of volcanic ash dispersion of Soputan in Indonesia, which erupted in December 2018 with the combination of the PUFF and Lagrangian methods. These combination methods gave a better result because it included the advection, diffusion, sedimentation vector, the geographic factor, wind area, eruption time and duration, and lifetime particle in the air. The simulation result was compared with the satellite image from Volcanic Ash Advisory and calculated the area ratio (AR) as well as the angular deviation (α).

A Prototype of liquid waste polluted water measurement system based on refractive index, salinity, and magnetic field parameters, has been developed. The instrument consists of Potentiometer, Light Dependent Resistor (LDR), conductivity sensor, Hall Effect sensor, and microcontroller. Potentiometer and LDR sensors are used to measure the refractive index, a conductivity sensor as the salinity measurement device, Hall Effect sensor as a magnetic field detector, and Arduino UNO as the control system. Each sensor has been characterized using a standard measuring instrument to determine sensor sensitivity. The characterization results showed that the refractive index sensor has a sensitivity of 321.8 mV/refractive index unit and a relative error of 0.35%. The conductivity sensor has a sensitivity of 415.2 mV/ppt and a relative error of 5.26%. The magnetic field sensor has a sensitivity of 0.0077 Volt/Gauss and a relative error of 4.29%. The prototype was used to measure the water quality of an artificial wastewater and river water samples. The artificial wastewater was made of the composite of water, salt, and liquid soap with different concentrations, and the river water samples were taken from ten different regions. The results show that the addition of salt and liquid soap concentration was directly proportional to the refractive index, salinity, and magnetic field. All samples have salinity below the normal threshold of <0.5 ppt.

One of the most straightforward approaches that widely used to solve the neutron transport equation is the diffusion equation approach. The diffusion equation describes the individual behavior of the average neutron trajectory when interacting with matter. Usually, the neutron diffusion equation is obtained under the assumption that scattering is isotropic in the laboratory system of coordinates, and neutrons have the same energy and region is homogeneous; this called a one-speed diffusion equation. It leads to the diffusion coefficient to be independent of the spatial position; the volume of the reactor is constant, and the number density of the fuel atoms is also relatively constant. In this study, multi-group neutron diffusion characteristics were introduced in two ways. First, they vary with energy in the finite slab reactor core using a one-dimensional multi-group diffusion equation with the Gauss-Seidel iteration method. Second, using Fick's law directly. The study used macroscopic cross-sections in the U-PuN fuel cell level as initial input for 70 energy groups. The data library used is JFS-3-J33 for 70 energy groups, which is the library data of SLAROM computer codes from JAEA Japan. The first way indicates the diffusion coefficient characteristics of U-235 and Pu-239 fuel isotopes firmly have the same pattern in each group energy. They have fluctuations throughout the fast, intermediate, and thermal energy group regions because both isotopes are fertile material. On the other hand, the diffusion coefficient of U-238 fuels isotope tends to be stable in each energy group. This event occurs because the isotope of U-238 is natural uranium, which is included as a fertile material. The second way shows the diffusion coefficients characteristics of the nuclear fuel isotopes firmly have the same pattern in each energy group, especially in the fast and thermal energy group region. They have fluctuations only throughout the intermediate energy group regions because, in this area, there is a resonant region.

The aim of this research is to study the magnetohydrodynamic (MHD) phenomenon on the solar surface by apply differential equations. We are trying to understand and explain the processes from observable solar layers to deeper layers, by using plasma theory and data analysis that may construct understandings to solar physics. This research is done by combining the MHD simulation and data of solar observation results. MHD simulation was carried out in the theoretical laboratory, physics department, UM. Data on the sun's observation were obtained from LAPAN Watukosek Jawa Timur. The results of this study are the coronal solar helmet streamer structure is degraded and the MHD equilibrium ends before it erupts. This is shown by the simulation results using data obtained from observations, namely the degradation of colors from the strongest to the weakest. This shows the existence of weakening energy before finally experiencing an eruption. The phase was terminated by the coronal mass eruption (CME). Activity to the surface of the corona to the inner layer is outside our technology to observe directly. Therefore, the conclusions in this article are made using the plasma flow approach at high temperatures.

Assessment is an important component in education that always needed. To improve the quality of education can be done by improving assessment learning quality and system. This study aims to determine the performance of students of grade X SMA N in Bandung West Java Indonesia school with 34 participants on a two-dimensional collision concept. This research is descriptive research which is conducted to examine the condition and situation that is happening, so that gives a fact-based description found in the school in other to find information factually. Problem studies that analyzed are the student's performance after using PhET simulations on two-dimensional collision concept. The instrument utilized in this study is a written test in the form of students' worksheets of momentum and impulse. Student worksheets test shows the average percentage on student performance in understandings concept of two-dimensional collision concept is 67.14%. These data indicated that student learning performance in good category. Learning by using virtual laboratory can provide more meaningful learning especially in physics concept that cannot be presented and observed directly in daily life.

Dye-Sensitized Solar Cell (DSSC) is one of photovoltaic (PV) cell which converts solar energy into electrical energy, by using dye as its active material. In this study, total energy and bandgap energy of natural dyes such as theaflavin and cyanidin-3-glucoside (C3G) molecules were calculated using density functional theory (DFT) method via quantum espresso software. Optimization of some calculation parameters such as cutoff energy, pseudopotential and k-point have been done to ensure minimum total energy of dyes molecule. Based on the result, the total and bandgap energy of theaflavin is 10172.80 eV and 1.96 eV, while the total and bandgap energy of the C3G molecule is 8442.26 eV and 1.73 eV. From these results, further investigation is necessary to the opportunities of the two dyes as DSSC sensitizers.

A Study of The CsPbI₃ Two-Phase Electronic Structure Has Been Made Through Calculations Using the Density Functional Theory Method. Perovskite metal halide is used as a light-absorbing material on solar cells. This material has a high level of stability and an easy fabrication process. Also, the conversion efficiency has reached 10.1%. The two crystalline phases used are the cubic phase and the tetragonal phase. The electronic structure discussed includes the ribbon electronic curve, as well as the DOS (Density of States) curve, PDOS (Projected Density of States) curve. To find out the electronic structure, and optimization calculation is performed, namely variations in lattice constants, k-points, and cut-off energy. This optimization is done to get the structure with a minimum total energy so that its stability can be achieved. It is known that the bandgap energy value of the CsPbI₃ cubic is 1.44eV on the electronic and DOS curve curves. Whereas the band gap energy value of tetragonal CsPbI₃ is 0.6 eV on the electronic band curve and DOS as well. This shows that CsPbI₃ can be used for the perovskite semiconductor material.