Table of contents

UNNES reservoir basin as a characteristic of the Conservation University is around 12 years old. This relatively long span of time has never been carried out a physical study of a subsurface structure. This study aims to describe the subsurface layer based on gravity data. The method used is to use gravity by calculating the elevation of each measuring point and by tidal correction and drift correction. Both of these corrections are to reduce the tidal and fatigue effects of the gravimeter. Measurements were done in July 2019 (dry season). The results of the study based on observational gravity data indicate that the value of a large gravity is in the north-south part and the smallest value is in the west part of the reservoir basin. The structure of the first layer which has an average density of 2.7 g/cm³ thick 75 m below the surface. The second layer is dominated by andesite rock with an average rock density of 2.8 g/cm³ thick 50 m below the first layer. While the lowest layer is a layer dominated by basalt rock with an average rock density of 3.1 g/cm³ thick more than 40 m below second layer.

Photoresist is an essential chemical used in patterning the microelectronic devices. To ensure the sustainability of the supply of raw materials of microelectronics industry such as photoresist need to look for alternative materials that are more eco-friendly. This study used natural ingredients of Hibiscus tiliaceus L. flowers extract. The manufacture of photoresists carried in four stages, the manufacture of Hibiscus tiliaceus L. flowers extract, the manufacture of thin film Hibiscus tiliaceus L. flowers extract, the manufacture of resist and the manufacture of thin film photoresist. The manufacture of Hibiscus tiliaceus L. flowers extract is done with mass fraction variations using distillation methods. The optical properties of Hibiscus tiliaceus L. flowers extract was characterized using ocean optic Vis-NIR USB 4000. The functional group was characterized using the Perkin Elmer Frontier FT-IR, while the surface structure was characterized using the Digital CCD Microscope MS-804 Scopeman and the electrical properties were characterized using the Elkahfi 100 I-V Meter. The density of the resist is characterized by the mass per volume method. Thin film of photoresist is grown through the spin coating method with a voltage of 10 V for 60 s and heating to a temperature of 200°C for characterization of surface structures and optical properties. Photoresist is tested for sensitivity by giving exposure to UV and X-ray radiation sources to photoresist material. The resulting photoresist has a value of absorbance that is located in the wavelength range of 350 to 1050 nm with a maximum absorbance value of 0.07 to 0.3 at the wavelength of the g-line, h-line and i-line.

Al doped ZnO (AZO) thin films were deposited using dc magnetron sputtering on corning glass substrate has successfully done. After deposition, the samples were annealed in vacuum ambient at temperature of 300 °C with variation in annealing duration of 0, 30, and 50 minutes, respectively. The structural, optical and electrical properties of these films have been investigated as a function of annealing duration. Thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis spectrometer and I-V measurements. AZO thin films without annealing treatment was showed amorphous structure. However, after annealed at 30 and 50 minutes, the films obtained were polycrystalline with a hexagonal wurtzite structure and preferred orientation in the (002) plane. Average optical transmittance of the AZO thin films was over 85%. In Addition, the electrical resistivity is reduced from 1.85 × 10⁶ Ωcm to 1.93 × 10² Ωcm when applying annealing treatment. It's can be concluded, the annealing treatment in vacuum ambient was improved the crystallinity and simultaneously improved optical and electrical properties of AZO films.

ZnO:Cu thin films were deposited on corning glass substrate using sol gel method with different concentration of Cu (0, 1, 3, and 5%) has been done. The effect of the different Cu concentration on the structural properties of these films was studied in detail. Based on the XRD result, the ZnO thin films undoped and doped Cu are polycrystalline with hexagonal wurtzite structure and has preferred orientation is c-axis. All peaks of ZnO thin films undoped and doped Cu shows that reflection peaks associated with (100),(002) and (110) planes. The film quality was improved with the increasing of the Cu concentration. The value of the lattice constant a and c was found to be increased with increases of the Cu concentration. Changes in the lattice constant affect the bond length of ZnO (L) and the volume of one hexagonal system unit (V). The lattice parameter also affects to the crystallite size. The crystallite size was increased with Increasing of the Cu concentration and the lattice parameter. Furthermore, the strain value of the film decreases with increases of the Cu concentration. Lattice strain that has decreased is due to the cavity around of the formed film. Cavities between atoms also affect the density of the dislocation. The larger cavity between atoms on the films that makes the dislocation density becomes smaller.

Reservoir basin is one of the important components in water conservation which is very supportive in Green Campus activities. The importance of information on the sub-surface layer surrounding the reservoir basin is the first step in managing and empowering the location. The purpose of this research is to identify the subsurface layers in the UNNES reservoir basin. The method used in this research is the resistivity geoelectric method with the Wenner configuration. Measured track totaling three which is located on the side of the UNNES reservoir basin with a track length of 75 m. The results of the identification of the subsurface layer get four layers, namely the layer of tuff sand/water with a value of 1.22 - 2.79 Ωm, a layer of clay with a value of 6.41 - 14.7 Ωm, a layer of sand / gravel with a value of 33, 7 - 77.3 Ωm and lava flow / breccia flow with a value of 77.4 - 177 Ωm.

Considering a set of condensates as N indistinguishable noninteracting quantum oscillators and replacing an available volume with a harmonic volume, we derived an ideal gas model by applying the canonical partition function via the thermodynamic relation. In this case, we take a longitudinal part of the three-dimensional Gross-Pitaevskii equation in which the effect of gravitation of earth works. Since we used the time-independent perturbation theory, to include gravity effect, we must put the higher coefficient in the formulation of each energy state whose value is determined by the separated amplitude formula in each state. It will also be shown that even though the equation of state represents an ideal gas, the appropriate heat capacity approaches Einstein's solid-like model if the certain conditions are employed.

ZnO/CdS/CdTe solar cell performance modeling has been done using AFORS-HET. The performance of solar cells is assessed based on the thickness of the CdTe absorber and device temperature. The thickness of CdTe varies from 100 nm - 5 μm and the temperature of the device is varied from 295 K, 300 K and 305 K. The characteristic I-V results show that samples with higher CdTe thickness have greater performance efficiencies. Conversely, the temperature variation of the device shows that the higher temperature of the device, the performance of solar cell efficiency will decrease. The optimum performance of ZnO/CdS/CdTe solar cells is owned by solar cells with a thickness of 4,500 nm CdTe absorber with V_OC, J_SC, FF, and efficiency values at 300 K device temperature respectively for 967 mV; 27.6 mA / cm2; 86.95%; and 23.21%.

Non-Destructive Testing (NDT) is a technique for detecting a defect in an object without causing damage. NDT technology can be utilized in the arts for inspection purposes. The NDT technique that can be used for the inspection of art pottery is digital X-ray radiography. It can inspect until the contents inside the art pottery without causing damage. To obtain a high quality of watermarked art pottery image using digital radiography, the radiation exposure factors should be optimized. In this work, optimization was done by varying the voltage, current, and exposure distance. Then, the radiography images were analysed using Contrast to Noise Ratio (CNR). From the analysis, it can be determined that the optimum exposure factors are 60 kV of voltage, 16 mA of current, and 100 cm of exposure distance.

We considered the effect of the electric field on the spin stiffness in the zigzag graphene nanoribbon by means of first-principles calculation. To reach the intention, a fixed planar spiral structure was formed together with a spin constraint method in the antiferromagnetic edge states of the zigzag graphene nanoribbon. The spin stiffness was then obtained by fitting the total energy difference in a set of spiral vector via the Heisenberg model. We showed that the trend of the spin stiffness changes as the electric field increases up to certain value. This means that the electric field can control the spin stiffness in the zigzag graphene nanoribbon.

Learning physics problems still appear in many parts of the world. Along with this, the development of civilization demands the development of education to produce the skills that are the ultimate in every human being. 21st Century skills are skills that are relevant to the demands of the development of civilization. Pre-service Teacher needs to be prepared to overcome the problems of learning Physics by following with the times. This study aims to develop a skill-oriented Momentum teaching material of the 21st Century and the industrial revolution. This research is development research with stages: 1) Analysis of potential and problems, 2) Product design, 3) Design validation and design revision, 4) Product testing, 5) Analysis of trial results, and 6) final product assembly. The research instruments were in the form of observation sheets, tests, and questionnaires. The data analysis technique uses descriptive percentages. The results of the study in the form of scratch-assisted teaching materials that have characteristics provide opportunities for students to make momentum simulations independently. The percentage of the material validity score was 92.23% and the media validity was 88.64%. The results of the trial show that the acquisition of each skill score is more than 71, so it can be concluded that the materials teaching developed are practically used and effective to build 21st-century skills and industrial revolution 4.0.

This Quasi Experimental research aims to analyze the learning achievement of grade XI students of Public Senior High School in Bekasi, West Java-Indonesia. Two experiment science classes were selected as samples by using purposive random sampling. The 1^st sample class was taught using laboratory kit activity; whirls the 2^nd sample class was using PhET interactive simulation. The data was collected using written test to measure students' achievement and then statistically analyzed using t-test to determine the hypothesis either be accepted or not. The normal distribution and homogeneity tests were also applied to know that the data was normally distributed, and all the variances were homogeneous with level of significant >0.05. The t test result indicated that the value of tcalculation (3,052) was greater than and tTable (1,667) that shown that there was a significant difference between the learning achievement of class 1 and 2 with mean value of 70.85 and 63.26, respectively. In conclusion that learning process using PhET interactive simulation provided higher students' achievement compared to those class which apply laboratory kit activity of gas kinetic theory.

The perturbation method is used to see changes in solutions that occur when attenuation is of little value, as in the phenomenon of waves with weak attenuation and which subjected to coercive force. Therefore this study aims to find solutions to solve the wave equations that experience weak attenuation and which subjected to coercive force. The method used is the study of literature and computation with MatLab. Based on the research results obtained that analytically non-homogeneous waveforms can not provide general solutions for differential resolution. Whereas computationally the results obtained are, the wave model with weak attenuation and the wave model with coercive force have amplitude values that change for time and for time wave models that subjected to coercive force has an amplitude value that increases compared to without coercive force.

This study aims to determine the different ability of free body diagram (FBD) representation in Newton's Law based onstudents' thinking style. The subject of this research is the students of 10^th grade from science class at state senior high school 1 of Prembun. The data analized is the results of cognitive test and students' thinking character questionnaire. The data were analyzed by using quantitative method. Based on the result, can be concluded that there is no difference between the ability of free body diagrams representating with a category sequential concrete, sequential abstract, random concrete and random abstract, which in the four categories of thinking styles included in the criteria need improvement.

One of the problems encountered in the making of dye-sensitized solar cell (DSSC) is the efficiency still relatively small compared to the conventional solar cells made from silicon. In this study, microwave irradiation was used in the process of coating Musa Accuminata Bract extract, with the aim that more anthocyanin pigments absorbed in the work electrode. This anthocyanin can make more sun energy absorbed and enhances efficiency. The resulting Musa Acuminata Bract extract was characterized using Ocean Optic Vis-Nir USB 4000 to determine its optical properties and produce maximum absorbance of 1.7353 at mass fraction of 0.45. The irradiation process was carried out using Electrolux Microwave Oven (EMM 2308X) at 140 W. After the DSSC sandwich is arranged, the sample is characterized using an El-Kahfi 100 I-V meter to determine its electrical properties. DSSC without microwave irradiation has an efficiency of 0.000345%, while with microwave irradiation, it could yield efficiency of 7.26%. This proves that microwave irradiation can improve DSSC performance.

Films used in Rontgen aperture by conventional radiography process yielding a fluorescent-based digital radiography have been conducted in medical-physics laboratory, Unnes for several applications. The continued research was improving the 2D radiograph imaging to be 3D, i.e. the object was rotated and X-Ray radiated simultaneously that yielded a 2D radiograph data by reconstruction and rendering. These covered a development of simulation object, an algorithmic modeling of scanning simulation and FDK (Feldkamp, Davis, Kress), and finally utilizing the algorithms resulting in 3D radiograph. In the future, this cheap technology would be a benefit in dentistry, because this technology is not popular nowadays, an implication of the expensive cost. The development process covered; software developing stage of CBCT (cone beam computed tomography) system in Phantom, data analysis, and finally reaching the result: CBCT model in laboratory scale. Prototype development of CBCT system can be done through study of the system in laboratory scale and then integrating the CBCT system for validated system in laboratory scale. According to the background above, we need innovation in CBCT system supporting the development of CBCT system aperture that leads to ease the dental implant installation in dentistry. At this level, CBCT prototype was used in early validation of the concept of CBCT technology in limit quantity and laboratory scale.

This micro-seismic survey was conducted to analyze the stability in Kalialang Village, which is one area that surrounding of the prone to landslides areas. Retrieval of data using a seismometer with many measurement points of 24 points. Data analysis in this study involves the Horizontal to Vertical Spectral Ratio (HVSR). Ground shear strain calculation is calculated by dividing the value of the soil layer deformation by the thickness value of the sediment layer and multiplied by the amplification. Data processing results show that Kalialang Village has a ground shear strain value that varies from 1.62 × 10⁻⁴ to 5.25 × 10⁻⁴. Based on the ground shear strain value it's got, then the event in the region are crack in the bedrock and the settlement.

We discuss the transmission characteristics of photonic crystal with two defect illuminated by a continuous wave of Transverse Electric (TE) mode at low terahertz frequency. To study its performance we solve numerically the corresponding Maxwell equations by means of finite difference frequency domain method. By varying the angle of incident, width of defect layer and refractive index in the second defect layer, it is found that the device exhibits a significant transmission enhancement at two wavelengths with typical changes. We also demonstrate its potential applications for biosensor platform

A short semester was an optional semester for students and the duration was eight weeks including a final exam. This research was conducted to describe student learning outcomes about entropy in thermodynamics. The research was conducted in the thermodynamics class of Physics Department Universitas Negeri Semarang 2018/2019 which was taken by 16 students as the object of this research. The learning outcomes were analyzed from data taken from final exam scores. The data were analyzed by using descriptive qualitative analysis. Based on the result, the score (student learning outcome) was 8,8 on average from the maximum score was 16. It could be concluded that thermodynamics learning outcomes at a short semester program of the entropy concept were in fair category.

Students must have communication skills to communicate their ideas and thoughts. The communication skill of students plays a role in physics learning because it can change the learning situation in a better direction. In addition to communication skills, collaboration skills must also be owned by the students in the learning of physics, one of which is used to conduct observations in groups. The purpose of this research is to know the relationship between communication skills and students' collaboration skills, especially in physics. This research is experimental and the sample was taken by purposive sampling technique. In the results, there is a very high relationship between communication skills and students' collaboration. The score students' communication skills was 0.876, indicating that there was a direct relationship between students' communication and collaboration skills, where students' communication skills increase with the increasing of collaboration skill. Additionally, learning used of video tracker software created new knowledge and skills.

Isopulegol is an intermediate compound for synthesis some fine chemical and used in the pharmaceutical, soap and tooth paste industry. Conversion of citronellal to isopulegol in catalysed cyclization reaction has been investigated. Isopulegol can be produced by using cyclization reaction of citronellal with Ni/beta zeolite and Cu/beta zeolite catalysts. Citronellal has been isolated from citronella oil by fractional distillation under reduced pressure. The structure of product were analyzed by using GC, GC-MS and FTIR. The catalysts were prepared by using impregnation method and characrized by using XRD and SAA instruments. Citronellal cyclization was carried out at 180°C for 4 hour. Based on GC and GC-MS analysis, it was shown that concentration of isolated citronellal of 84.26%. XRD analysis of catalysts showed that the metals were impregnated with beta zeolite. Citronellal cyclization using Cu/beta zeolite catalyst produces 69.31% isopulegol and Ni/beta zeolite catalyst produce isopulegol at 29.68%. The Cu/beta zeolite catalyst has an activity of 90.20% and selectivity of 80.98%. The activity of Ni/beta zeolite catalyst of 42.53% with selectivity of 76.60%. These results indicate that Cu/beta zeolite catalyst is better than Ni/beta zeolite in citronellal cyclization.

One of the solutions for fossil fuel crisis is to find alternative energy based on renewable materials. In this research, catalytic cracking of used cooking oil has been investigated to produce biofuel using Cr-charcoal catalyst. The charcoal was produced from solid waste (shell) of palm oil industry. Chromium solutions with various concentrations (1%, 2%, and 3%) were impregnated into charcoal to produce Cr-charcoal catalyst. The catalysts were used for catalytic cracking of used cooking oil at three levels of temperature: 450°C, 500°C and 550°C. The XRD patterns and SEM images of the catalyst showed that the catalyst was in amorphous form. SEM-EDX analysis showed that the Chromium was impregnated into charcoal successfully with amount of Chromium absorbed into charcoal was 0.51%; 1.07% and 14.38% respectively. The SEM images also showed that charcoal as supported catalyst and Cr-charcoal catalyst have unique pores. The highest liquid oil fraction was obtained by catalytic cracking at 500°C using 3% Cr-Charcoal catalyst. The liquid product of this process was mainly diesel oil with 8-24 carbon atoms (86.35%) and the rest was liquid product with 6-7 carbon atoms.

Fe-N-TiO₂ photocatalyst has been used in water splitting to produce hydrogen. Templating agent and dopant modification intends to determine the optimum composition with the best characterization and the highest production rate in visible light. Fe-N-TiO₂ is synthesized using a sol-gel method with a various PEG and N weight percent. The variation of PEG is 2, 3, and 4% while N is 20, 25, and 30%w/w. Photocatalyst is characterized using DR-UV to find the band gap, XRD to see the crystallinity, and FTIR to know the functional group. Hydrogen gas from water splitting is analyzed using GC-TCD. Fe-N-TiO₂ with 20wt% N can decrease up band gap to 2.56 eV. Photocatalyst with 4% PEG accelerates gelation time to 164.33 hours. The calculation of PEG anatase phase is 86.86% while the crystallite size is 44.26 nm. Synthesized Fe-N-TiO₂ has major absorbtion at 520 cm-1 which is a region of Ti-O. From the activity test, Fe-N-TiO₂ with 2% PEG and 20wt% N produces 0.076 μmol/hour hydrogen.

In 2015, the United Nations Environment Program (UNEP) revealed that there are 280 million tons of plastic produced globally each year This research was conducted to convert plastic waste to be useful products. Polyethylene Terephthalate (PET) is converted into gas and coke using thermal cracking method and a stainless steel batch type reactor. Looking for the effect of temperature variations on the thermal cracking of PET plastic waste and studying the kinetic phenomena are the purpose of this research. A total of 40.17 grams of Polyethylene Terephthalate (PET) plastic waste was cracked in a batch reactor at 450, 500 and 550 °C for 15, 30 and 45 minutes. The highest percent yield of gas (89.92%) was resulted at 30 minutes of reaction time and 550 °C of the reaction temperature. The highest percent yield of coke (26.01%) was resulted at 45 minutes of reaction time and 500 °C of the reaction temperature. The activation energy for the highest percent yield of coke, 26.01% is -9,257701 kJ/mol, otherwise the process needs to be revised to get the positive activation energy.

Tapioca flour industry produces starchy wastes. Improper handling of this waste can cause environmental problems. The bioconversion of starchy waste to bioethanol has been widely performed. However, the utilization of solid waste from the tapioca flour industry for bioethanol production is still limited. This research is a preliminary investigation to determine the level of ethanol produced from cassava pulp and peel by the fermentation process. Cassava pulp and peel were prepared for the delignification process, hydrolysis process, fermentation process, and finally, the purification process. The fermentation process was carried out by varying fermentation periods, i.e., 2, 4, 6, 8, 10, 12, and 14 days. The highest ethanol concentration at 6.2% was obtained after eight days of fermentation.

Cocoa contain polyphenols and potential antioxidants. Polyphenols is beneficial to human health and used for cosmetic and food manufacturing. The production of cocoa and its derivative products resulted liquid smoke, tar and charcoal. Pyrolysis is able to overcome the accumulation of those production waste. In this study, pyrolysis was conducted at temperature 114-514°C. Analysis of cocoa shell content from Bulukumba district was lignin (42.28%), cellulose (44.55%), hemicellulose (10.02%). Analysis of cocoa shell content from Enrekang district was lignin (45.61%), cellulose (37.61%), hemicellulose (6.40%), and others (10.38%). GC-MS analysis for liquid smoke of cocoa shell from Bulukumba resulted acetic acid (18.39%), butyrolacton (6.27%), oxetane, 2-propyl (4.45%), 2,6-dimethyl-7-octen-3-ol (6.48%), and hexadecanoic acid (4.36%). GC-MS analysis for liquid smoke for cocoa shell Enrekang resulted acetic acid (25.78%), propane diamide (2.18%), acetamide N–methyl (4.0%), cyclopropyl carbinol (12.57%), 2-propanoic acid-2-methyl (7.83%), phenol 2,6-dimethoxy (2.72%), 1,6-anhydro-beta (5.83%), alpha-beta-D ribopyranose (1.76%). While XRD analysis for cocoa shell from Bulukumba and Enrekang showed that the degree crystallinity are 40.15% and 22.22%, respectively. The use of pyrolysis of cocoa shell can reduce carbon emission as environmental pollution and increase the economic value.

Synthesis and characterization of electrospun fiber chitosan/polyvinyl alcohol/polyvinylpyrrolidone have been studied. Electrospun fiber is a fiber produced from the electro spinning process that utilizes the power of electricity to produce polymer fibers with nano to micro diameters. The purpose of this study is to synthesis and characterize electrospun fiber from chitosan/polyvinyl alcohol/polyvinylpyrrolidone. The mixture of chitosan/polyvinyl alcohol/polyvinylpyrrolidone solution is placed in an electrospinning capillary with a diameter of 0.57 mm with an electrospinning voltage of 25 kV and a distance between the tip of the spinneret and the collector by 10 cm. The resulting electrospun fiber is analyzed with fourier transformed infrared spectroscopy and scanning electron microscopy. Based on the FTIR spectra, it was found that the electrospun fiber produced consisted of chitosan, polyvinyl alcohol and polyvinylpyrrolidone. SEM analysis results show that the electrospun fiber obtained has an average diameter of 93.1 - 168.7 nm.

In previous studies, there has been investigation about the levels of macro and microelements in liquid organic fertilizer and solid organic fertilizer made from Tilapia fish waste, indicated that the required standard of fertilizer could be met. Therefore, this research aims to study the application of Liquid Organic Fertilizer (LOF) and Solid Organic Fertilizer (SOF) from Tilapia fish waste to Central Sulawesi superior Jackfruit plants from Tulo and Beka areas. The factorial Block Random Design with two factors was used to analyze the growth of two kinds of Jackfruit plants and two kinds of fertilizer, with three times replications. The observation method was non-destructive measurement by using several parameters of growing plant standard. The result shows that all parameters measured among the combination of two kinds of Jackfruits, two kinds of fertilizers and three replications in terms of plant developing growth were no significant difference. The analyses of nutrient levels in the two kinds of fertilizers met the needs of Jackfruit plants.

Ginger is one of the plants that is rich with phenolic compounds. This research was aimed at determination of the total phenolic content and antioxidant activity in the rhizome of ginger. However, there is only few information available about the comparison of phenolic compounds and antioxidant activity in the three varieties of ginger. This research employs a descriptive quantitative research using extracted dried gingers on two types of extraction processes, i.e. infusion and decoction. The phenolic compound analysis is conducted by using the Folin-C method, while antioxidant activity was conducted by using DPPH and measured by using Spectrophotometer. Based on ANOVA test result, the highest phenolic was red ginger 12.2533 mg GAE/g (infusion) and 22.9767 mg GAE/g (decoction) followed by emprit and elephant ginger. The highest antioxidant activity by infusion process was found in red ginger of 79.83 % followed by 70.43 % and 61.70% in emprit ginger and elephant ginger. Conversely, the highest antioxidant activity by decoction was found 78.76 % in emprit ginger, followed by 70.56 % and 60.93% for red ginger and elephant ginger. Ginger have sufficient antioxidant activity on extraction by infusion or decoction and the red ginger have a higher phenolic content.

The liquid fuels from biomass produced through fast pyrolysis is very promising due to their high energy density and carbon neutral properties. Therefore, the pyrolysis of Indonesian mahogany wood at various temperatures (450-600°C) was carried out in this study. A fixed-bed reactor was used in the pyrolysis experiments. The produced bio-oil, bio-char, and gaseous product were recovered and quantified. This study showed that the higher the temperature, the higher the yield of the bio-oil (39.40 wt% at 550°C). However, the pyrolysis at a temperature higher than 550°C produced a lower yield of bio-oil, possibly due to severe cracking resulting in more gaseous products. The produced bio-oils showed good characteristics, i.e. density of c.a. 1,17 g/mL, viscosity of 3.93-5.67 poise, total acid number of 0.66-0.79 mg-KOH/g, and calorific value of 16-18 MJ/kg. The water and volatile (acetic acid, furfural, phenol, and stearic acid) contents of the produced bio-oils were also quantified by using a gas chromatograph. The bio-oils with a low water content (13.46-15.90 wt%) and volatiles (0.1-2.9 wt%) were obtained, indicating high energy density and production of heavy molecules, respectively. The high acid number was likely from the heavy acids that could not be detected by the gas chromatograph.

Volcanic ash is a natural pozzolanic material with high mol ratio SiO₂/Al₂O₃ but low in CaO. This research aims to study the volcanic ash geopolymer characteristics related to CaO addition. Geopolymers are prepared by mixing volcanic ash, alkali activator solution, sodium silicate, and calcium oxide. Calcium oxide added varies 5–135 g with each interval is 5 g in Solid/Liquid (S/L=1.83) ratio. Geopolymer characteristics investigated include setting time, compressive strength, resistance to sulfuric acid and mineral phase. The results showed that the more CaO was added, the shorter the setting time and the greater the compressive strength until it reached optimum. The amount of optimum CaO that added is 30 g, with the setting time 2.61 hours and the compressive strength 36.26 MP better than the volcanic ash geopolymer without CaO as 103 hours in setting time and 20.34 in compressive strength. Volcanic ash-based geopolymer at the optimum CaO addition proved to be better than cement mortar, which has a shorter setting time, greater compressive strength and greater resistance to sulfuric acid. Mineral phase analysis by XRD shows that the optimum geopolymer containing an amorphous phase with a major mineral is quartz and sodalite.

Used cooking oil is the largest waste that can be converted into biofuel as a renewable alternative energy source with catalytic cracking process. In this study, used cooking oil was cracked using a Cr-Carbon catalyst. The charcoal was produced from solid waste (shell) of oil palm industry. Three different chromium concentrations (1, 2, and 3%) were used for the ion-exchange process of Cr-charcoal to produce the catalyst. These catalysts were used for the catalytic cracking of used cooking oil at three levels of temperature (450, 500, and 550°C). X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were used for catalyst characterization. SEM-energy dispersive X-ray spectroscopy (EDX) analysis indicates that Cr was successfully adsorbed into the catalyst. The highest oil fraction was obtained from catalytic cracking of used cooking oil at 450°C using Cr-charcoal catalyst synthesized using 1% Cr solution.

α-Pinene in turpentine oil can be processed further to produce high value derivative compounds. One of the chemical process that can be used to increase of the value of α-pinene is by methoxylation by using certain catalysts. This study aims to determine the effects of time, temperature, and type of catalyst in the methoxylation of α-pinene. Characterization of the catalyst include: crystallinity by XRD (X-Ray diffractometer), the functional groups analysis by FT-IR (Fourier-Transform Infrared Spectroscopy), surface area of catalyst with SAA (Surface Area Analyzer), and the acidity test by gravimetric method. Modification of the catalyst with NiO does not change the crystal structure of Y-zeolite significantly. Methoxylation was carried out in a modified batch reactor with mixer at various temperatures 40, 50, 60°C and time variations for 1, 2, 3, 4 hours. Reaction products were identified by GC (Gas Chromatography) and GC-MS (Gas Chromatography Mass Spectrometry). The product of α-pinene methoxylation was found to be patchouli alcohol. The highest selectivity (67.06 %) and conversion (75.41%) were obtained at the temperature of 60°C and at reaction time of 4 hours with NiO/ZY catalyst. NiO/ZY catalysts is more selective to be used in the α-pinene methoxylation compared with H-ZY.

Proximate analysis is a chemical analysis method to identify the food content of an ingredient. The proximate analysis component (protein, ash, fat, water and carbohydrate) correlate with the nutrition value of food. Many kinds of cookies were sold in the market but the data of proximate analysis results related with food quality is scarce. Three samples of cookies (one sample of soybean cookies and two of red bean cookies) that are available in Indonesian market were assessed in this study. Soybean cookie (sample no.387) was in accordance with Indonesian National Standard (INS) in terms of ash content and fat content. Red bean cookies (samples no. 388 and 389) met the INS requirements of protein and fat content. Whereas, all cookies samples were not INS compliant in terms of moisture content and carbohydrate levels (maximum 5% and minimum 70%, respectively).

This research was carried out to produce fuel (Oil Liquid Poduct/OLP) from catalytic cracking of a mixture of Polyethylene Terephthalate (PET) and fiber waste from palm oil. USY zeolite was previously ion-exchanged by three levels of Ni-metal concentration (1%, 2%, 3%) before used as catalyst in the cacking process. The catalytic cracking was carried out at rasio of sample to catalyst was 6:1, three levels of temperature (400°C, 425°C and 450°C) and three levels of reaction time (10, 20 and 30 minutes).The SEM images and EDX spectra of Ni-USY zeolite catalysts showed that all catalysts were in crystalline form of FAU framework. The highest of OLP percentage, 24.5%, was produced by catalytic cracking at 450°C for 10 minutes using Ni-USY prepared by ion-exchange using 2% concentration of Nickel Nitrate solution.

Encapsulation of cinnamaldehyde within polymeric and non-polymeric-based nanofiber matrix was investigated. Polyvinyl alcohol (PVA) was used as a polymeric matrix, and β-cyclodextrin (CD) was used as a non-polymeric matrix. The study is aimed to purify cinnamaldehyde from cinnamon oil and to encapsulate it within the nanofibers matrix. The purification step was carried out using spinning band distillation. On the other hand, the nanofibers were prepared through electrospinning. Three different formula were made, namely PVA/cinnamaldehyde, PVA/β-CD/cinnamaldehyde 5% and PVA/β-CD/cinnamaldehyde 10%. The yield of isolated cinnamon oil was 0.26% with 88.90% cinnamaldehyde purity in fraction III tested using GC and GC-MS. In advanced, the SEM images indicate that the average diameter of the bare nanofiber matrix was 75 nm. The diameter was decreased in the presence of cinnamon oils in all samples (range 50-65 nm). The inclusion complex formation was confirmed from FTIR data in the presence of a band at 1700 cm-1 that indicate the presence of the aldehyde group in both polymeric and non-polymeric nanofibers matrix.

The present work introduce synthesis low grade zeolite from fly ash and its application as urea slow release agent on Zea mays growth. The characterization of the synthesized zeolites were determined using X ray diffraction method and FT-IR spectroscopy. The zeolite that has been formed is added to urea fertilizer with a weight ratio of urea: zeolite as follows 1: 1, 1: 2, 1: 3. As much as 3 kg of soil is put in a polybag series and was added with 3 g urea slow release fertilizers. The polybags were planted with Zea mays plant 1 week in old at a depth of ± 5 cm. The plant growth parameters which include plant height plant, number and colour of leaves were observed every 7 days for 4 weeks Base on the diffraction pattern and IR spectra, the characteristics of the synthesized zeolite is matching with standard zeolite A. The use of urea slow release fertilizer on Zea mays plants showed better growth than using urea fertilizer without zeolite slow release ingredients. The treatment of soil with urea/zeolite 1:3 proven to produce the best Zea mays growth in interaction time 4 weeks.

This research aims to measure the innovative and creative character of Chemistry students in batik motifing of Chemical structures after learning natural products with the integrated STEM approach Ethnoscience. This type of research is a qualitative descriptive study with students of Chemistry education at UNNES taking Natural Product courses as a subject. Instruments data collection are questionnaires, interviews, the value of chemical batik products, and creativity in describing the meaning of batik motifs, appearance, origin, and color creations that have been designed on canvas. Chemical batik products produced by Ethno-STEM Project study were assessed by a research team and batik experts from Zie Batik Malon Gunungpati and batik experts from Pekalongan to determine which batik motifs are feasible to be produced as a form of research downstreaming. The final result of the batik design was decided that four decent batik products were produced in terms of motifs, color display, originals, and interesting creativity according to the judgment of batik experts. The four innovative and creative batik motifs with high scores are the anti-Christian batik motif, alpha pinene, curcuminoid, and Etbo-STEM carotenoids. From the results of this study it was concluded that the profile of innovative and creative character of students after learning with the Etno-STEM approach is very good.

Problem solving skills have important role on process science skills. These skills are part of 21^st century priority skills in Indonesia. This study aims to analyze the impact of learning based e-project on problem solving skills. This study employed methods a nonequivalent control group design. The subject of this research are students' of class XI MIPA 1 as class of experiment 1 and XI MIPA 2 as class of experiment 2 of SMA Yadika 9 Bintara, Bekasi, West Java with purposive sampling technique. Experiment class received treatment used e-project based learning. Experiment classes are giving the e-project to improve problem solving skills and control classes are learned conventionally. Data was collected through pretest and posttest results from students' in both classes. A t-test was used and it is found that level of significance is 0.006 (sig. < 0.05) proving that e-project based learning is effective to improve students' problem solving skills.

This study uses a quantitative approach with experiment. The population in this study were all students of the Faculty of Chemistry Education Teacher Training and Education (Guidance and Counseling) Indonesian Christian University (UKI), which follows the course of Chemical Physics 1. The purpose of this study was to determine the effectiveness of an interactive quiz quizizz as a medium of learning on-line evaluation of the course of Physical Chemistry 1. Data collection techniques used is a test instrument as much as 10 multiple-choice questions that have been testing the validity of the expert validator. Data analysis technique used is the non-parametric Wilcoxon Signed Rank Test. UseIBM SPSS 23. From the analysis of data obtained asymp. Sig. (2-tailed) was 0008, of which 0.008> 0.05. Because the value is less than 0.05, it can be concluded that the use of an interactive quiz quizizz as a medium for on-line evaluation of learning in the subject of physical chemistry 1 effective against student results.

The study aimed to find out the eligibility, effectiveness, and practicality of Nature-Based Student Practicum Worksheet on Acid-Base Titration towards students' Science Process Skills. Research and Development method was used in this study. The research was conducted at SMAN 1 Kendal. The result of the validation assessment showed that the developed worksheet was eligible, with an average score, given by the validators, was 89.58% for its materials and 90.28% for its media. The analysis result of the students' science process skills in performing practicum activities showed that 60 students reached a "very good" category and 9 students reached a "good" category; and the result of evaluation test revealed that 62 out of 69 students passed the minimum passing criteria (≥75). The reliability of the questionnaire for the students' responses was also tested; and it was revealed that its reliability was 0.89. According to the validation stage, the test results on a small and a large scale showed that the nature-based practicum worksheet on acid-base titration material towards students' science process skills was eligible, effective, and practical to be implemented.

This research aims to determine the effectiveness guided inquiry learning based of contextual to improve chemistry literacy ability of students. This is an experimental research with pretest-posttest control group design and cluster random sampling as sampling techniques. The samples of this research are two different classes of X MIPA. The ability of chemistry literacy is tested using chemistry literacy test and questionnaire. Data analysis uses T-test, N-gain, classical learning pass, and questionnaire data descriptive analysis. The result of this research provided average score of posttest of chemistry students literacy of experiment group 72.86 and 63.42 for control group. Classical learning pass of experiment group is 78.57% and control group is 38.71%. N-gain analysis result provided the ability of chemistry literacy in every aspect of experiment group is better than control group. T-test result are t_count 3.66 and is bigger than t_table 2.00, it means that the ability of chemistry literacy of students in experiment group is better than the one in control group. Questionnaire analysis result provided around 68% in good category. Based on research results, it can be concluded that by using guided inquiry learning based of contextual, students' chemistry literacy ability is improved significantly.

Skills in making scientific argumentations are crucial for students to understand science concepts. This study had used an argument-based learning (AbL) adopting Toulmin's Argumentation Pattern (TAP) and socio-scientific issues about heavy metals to promote the argumentation skills of the Indonesian university chemistry students. The effect of AbL in promoting the skills had been compared to Jigsaw and two-stay-two-stray (TSTS) learning that had been used in an earlier study. Data were collected using open-ended tests and observations. Quantitative and qualitative methods were employed to analyze the data. The results showed that the argumentation scale of the AbL-students was better than and significantly-different from the argumentation scale of those in the other classes (Tukey-test; p<.05). Distinct opportunities the students had in each class to use the TAP was the factor that produced the scale differences. The results recommend the importance of involving students in a learning that mostly promotes argumentation activities-like the AbL-to develop the students' argumentation skills in science.

The study intends to measure secondary level students' critical thinking skills. This study follows a survey method and is a part of a doctoral dissertation focusing on promoting critical thinking skills of environmental education for achieving sustainable development goals (SDGs). The data were collected by using the Critical Thinking Skills test on Environmental Education (CTSEE) comprises of 27 items. The participants were the 8^th grade students (N=444) from 13 secondary schools that cover four administrative districts of Bangladesh. The Instrument was adopted from previous research that consists of three aspects (Conclusion, Inference, and Identifying Bias) of critical thinking skills. The result shows that the students' critical thinking skills on environmental issues can be categorized into the poor and very poor category, and there are statistically significant differences between male and female students. The study will be used as the reference for developing students' critical thinking skills about the surrounding environment-related problem in line with achieving the globally decided environmental sustainability as well as sustainable development goals.

Much research has been done on creativity and the results can be easily found in journals, however, research on scientific creativity as a domain-specific creativity is still relatively rare. Therefore, it is necessary to study the literature to reveal the scope of research on the topic of scientific creativity. To achieve this aim, a literature review was carried out with the procedure adopted from the PRISMA statement. A total of 49 articles obtained from the IJSE, DOAJ, ERIC, IOP Science, ScienceDirect, and Springer Link websites, in the 2001-2019 period, were analyzed. The results showed that the three journals that published the most scientific creativity articles were JEP, IJSE, and CRJ. And, the three countries with the most contributing authors were Turkey, Indonesia, and Taiwan. Except for one critical review article, the research types of all articles analyzed were an empirical study, which consisted of at least five sub-topics of scientific creativity.

Building science literacy education in the 21^st century began to be developed again especially in primary schools. The purpose of the research was to analyze of ethnoscience-carica based of science literacy and character development by using guided inquiry model. The place of research is at two state primary schools in Wonosobo Regency, Central Java. The mixed methods research was used, with embedded experimental model design. The subjects research are 56 students from primary school. Data collection was done by using test, observation, and documentation. The result showed the positive correlation between the mastery of science literacy an ethnoscience-carica based on the healthy food and students' character is r = 0.58 (medium); and gain factor <g> = 0.70 (high). The conclusion of the research that the implementation of the guided inquiry model is to effective increase students' mastery of scientific literacy on the healthy food and students' character development.

The study aims to apply project-based learning through the application of laboratory quality to improve basic laboratory skills, instrumentation analysis skills, and critical thinking skills to solve problems. In the preliminary experiment, authentic assessment is used to measure the level of basic laboratory skills and instrumentation analysis skills. In project work with the application of laboratory quality procedures, authentic assessment is used to measure critical thinking skills. There are 99% who have a high and very high level of basic laboratory skills. The achievement level of instrumentation analysis skills with high and very high criteria for pH-meter instruments, conductometers, and spectrophotometers in sequence 94, 85, and 83%. Instrumentation analysis skills for UV-Vis spectrophotometers are the most difficult to master by students then followed by a conductometer, and a pH-meter. The project work design must implement laboratory quality procedures which include how to take samples, manufacture working solutions, prepare samples, make calibration curves, sample measurements, calculate and analyze data, and test validation methods. Method validation testing activities include linearity testing, LoD and LoQ calculations, precision and accuracy tests. There are 63% have a high level of critical thinking skills, and there are no very high criteria.

This study aims to describe the profile of students' creative thinking abilities. This research is a mixed study using the method of embedded experimental model. Quantitative data in the form of test results become the main data which is then triangulated with qualitative data from collected through classroom observation activities, asking students to fill out questionnaires, and conducting interviews. The subjects of this study are high school students who have studied the topic of linear motion. This topic was chosen because it has a characteristic that is the scope that can be presented with a variety of representations that can reveal students' creative thinking abilities. The selected school is a state high school with accreditation A with the assumption that students have received education with national standards. This means that it can be a benchmark for the success of a learning program in training students' creative thinking skills. Based on the results of data collection obtained information that the stimulation to encourage students to solve problems with a variety of display representation is still in the category of less creative. This is supported by field observation data that the one-way learning model, the conclusion of the questionnaire data confirmed from the results of the interview that students lack the opportunity to answer in creative ways.

Habits of mind are a great attitude obtained by the discipline of mind training as habits in action. The action is the consequence of habits of mind that assort cognitive, affective, and psychomotor. Habits of mind are a new trend in education besides high order thinking skills. The purpose of this research is to discover the mind habits potential of Biology students in their first year of college. The method of this research was a survey that involved 67 Biology students in the first year of a university in Pontianak, Indonesia. The data collected by using a questionnaire that contained 44 questions about 16 indicators of mind habits by Costa and Kallick. The data analyzed by using descriptive methods. The findings show that the students' mind habits are at a sufficient level, and there is no significant difference among 16 categories of habits of mind. Therefore, the freshmen of the Biology Department have good habits of mind potency with the highest percentage is flexibly thinking category (79,60), and the lowest is thinking and communicating with clarity and precision category (63,73). As a suggestion, students' habits of mind as part of thinking skills need to improve through the learning process.

The era of the industrial revolution 4.0 in the 21^st century demands people to develop skills in all sectors of life, including education and learning. One of the elements that supports learning is student creativity. In Science learning, creativity becomes an imperative aspect of learning Science in schools. This study aims to analyze the level of creativity of 7^th-grade students at SMP Negeri 8 Surakarta. The type of this research is descriptive research. The subjects of this research consisted of 263 students who were obtained from 8 classes. The instrument used in this study was a instrument test of the creative thinking skills consisting of eight questions. There are four aspects of creative thinking skill namly fluency, flexibility, originality, and elaboration. The results of the percentage analysis of each aspect showed that the fluency was 47% and it was categorized as the moderate category. Meanwhile, the other three aspects were categorized as the low category in which the flexibility was 26.94%, the originality was 21.24%, and the elaboration was 29.77%.

The introduction of Biotechnology subject started in SMP (9) and deepen in SMA (12). One of the topics on modern biotechnology products is Genetic Engineering technique to produce lipase enzymes. SMA student knowledge on this topics are still limited since the source of information used by teacher on learning process is generally based on the textbook and delivered through leatoring method. The use of learning media with virtual-technology based is expected to provide an illustration of information that make easier and more attractive to understand. In this study, two mediums were evaluated, including textual and video animation media. To test the superiority of video animation media, the test is carried out to SMA students in Lombok, by using same questions about student undestanding level between video animation and textual media. The evaluation shows that video animation improve the average outcomes, informative, attractive, and easy to understand. This feasability tests carried out by Biology teachers and student's responses. Therefore, video animation media can be used as Biotechnology learning media.

Pineapple Liquid Waste (PLW) is waste that has acidity characteristics and contains organic material which can be utilized as a substrate for bacterial growth. Researchers are trying to provide the latest breakthroughs to utilize Pineapple Waste (PLW) as organic fertilizer to reduce waste increases and increase agricultural yields. The purpose of this research is to find out the effect on the weight of pineapple and find out whether it will increase vitamin C levels in pineapple. This study used an Experimental Method, the design of the design used was a Complete Random Design Variety and analyzed using a multivariate test. the conclusion of this study is the variation of PLW has a significant effect on fruit weight p> 0.05 and on vitamin C levels p < 0.05, so that no significant effect on fruit weight and significant effect on increasing levels of vitamin C, so this research can potentially design learning resources for biology.

The large number of out-of-school children in Brebes district is handled by Back to School Movement (GKB) program. The program is implemented as a participation program for all stakeholders, district government, regional education organization, school principals, village heads, community organizations, and other society elements. How is Parereja village's role in supporting GKB program? This study is a case study, which researchers were as instruments and directly involved in the respondents' activities. The role of Parereja village in succeeding GKB was indicated by the description of series of activities in preparing it returning out of school children in their areas. Under the coordination of village head, Education Care Community Forum (FMPP) was having collaboration with existing community organizations. The series of activities included verifying and validating data for out-of-school children, continuing advocacy to out-of-school children and their families carried out by children's forum with a peer approach. In conclusion, the role of Parereja village with village FMPP together with partners was the key to the success of GKB program in Brebes district. Out-of-school children of Parereja village that joined PKBM were more than in formal schools. There were 76% successive additions and 35% from the previous year.

The nature of science (NOS) is a crucial aspect of scientific literacy and also a major goal in science education. To achieve science education goal, students' knowledge and metacognition are highly required. This study described Biology student's understanding of NOS and their metacognition at higher education. This study was a survey of semester-four students. Data on NOS was from the Views of Nature of Science (VNOS) questionnaire form B, and students' metacognition data was from the Metacognitive Awareness Inventory (MAI) questionnaire. Data were analyzed descriptively. The results showed that the average of biology students' NOS understanding is 60.35%. Based on seven aspects of NOS understanding studied, the highest achievement is in the empirical-based science aspect (68.69%), the lowest performance is in the subjective science aspect which is full of theoretical content (49.49%). Students' Metacognitive regulation has a lower average (77.4%) than metacognitive knowledge (81.33%). It is found that Biology student's NOS understanding is still weak, and their metacognition still needs to be fixed. This research suggests that biology student's NOS understanding and metacognitive awareness still needs to be upgraded through the learning process so that students would be scientifically-literate and successful in their higher education.

Mathematical literacy ability is the ability to formulate, apply and interpret mathematics in various contexts. This ability can help someone in applying mathematics to solve problems in daily life. This paper aimed to understand the mathematical literacy ability of the students of The Elementary School Teacher Education Program of Universitas Negeri Semarang. The data analysis was done by referring to the qualitative data model by Miles and Huberman. There are data reduction, data display, and conclusion/verification. The results are 75,57% of the students can formulate daily life problems into mathematical problems, 54,96% of the students have used logical reasoning, 36,64% of the students can draw a conclusion, 29,01% of the students can give an evaluation of the conclusions made.

Acid-base is one of the first abstract chemistry course that high school student encounter. Research shows that many students find difficulty on the definition, macroscopic and microscopic conceptual comprehend. This research has the aim to identify the student's conceptual understanding in acid-base course. The subject for this research is 145 students from government school 2018/2019 school year. The data collected through 16 questions of the three-tier diagnostic test and questionnaire. Three validators validate the question with an average score of 159 from 176. The average score for the questionnaire is 39.75 with good category, and the Alpha Cronbach reliability is 0.714. Analysis of the result shows that the student has several difficulties with acid-base conceptual. Classical result for 145 students are 28% of the student understands the concept, 4% lack of conceptual understanding, 43% misconception and 21% don't understand the concept of acid-base.

The purpose of this study was to determine (a) developing survey instruments for Teacher's Perception of Science Practices Learning (SPL) and (b) describing the perception of science learning practices. This research uses descriptive survey method. Respondents in this study were elementary school, junior high school and high school science teachers in the Central Java region, totals 74 teachers. The research instrument used was a science learning practice perception questionnaire. The instrument has gone through the stages of expert validation and empirical testing. The instrument validity uses exploratory factor analysis. Data analysed by descriptive. The research results that the perception of science teachers on SPL is not different. Elementary, middle and high school science teachers have enough categories. El dimension, EE, SDC elementary, middle and high school science teachers have enough categories. The dimensions of the EPK for elementary science teachers have enough categories, middle and high school science teachers are in good category. The dimensions of IT in elementary, middle and high school science teachers are good. Science teachers' perceptions of SPL are in the enough category.

The research aimed to calculate the increase of student's hierarchy concept map (CM) scores through the modification of problem analysis and learning issue (2^nd stage of problem-based learning (PBL)) using question instructional techniques. The type of research is classroom action. Research subjects were 36 X grade students. Research procedures: planning, action, observation, and reflection. Research data is the percentage of hierarchy CM score which is calculated based on the Expert CM score according to the material in each cycle. Data validity is done by confirming the percentage of hierarchy CM score with the result of interviews and documentation of the learning process in each cycle. The analysis techniques use reduction, presentation, and drawing a conclusion. The results show that the average increase in hierarchy percentage scores from pre-cycles to cycle I was 25% and cycle I to II was 38%. The number of students who experienced an increase in percentage hierarchy scores from pre-cycle to cycle I was 83% and cycle I to II by 90%, thus the modification of instructional techniques in problem analysis and learning issues PBL increased the students' CM hierarchy score.

This research intends to analysing the citation of articles that have published in science education journals indexed by SINTA (Science and Technology Index). The research objects were 19 journals that rated Sinta 1 to 6. The articles were analysed descriptive-qualitatively through Google Scholar. There were six aspects of analysis including (1) number of citations; (2) average citation; (3) the most-cited article; (4) the least-cited article; (5) the most-cited theme; and (6) the least-cited theme. The analysis revealed that the highest citation was articles published in Jurnal Pendidikan IPA Indonesia with a total citation of 2,679 from 2012 to 2019. The lowest number of citations was in Spectra: Jurnal Kajian Pendidikan Science, for having nine citations within two years. The most-cited article reached 178 citations. However, most of the published articles have not been cited yet. Moreover, the most-cited theme was a science learning strategy. In conclusion, the articles published in journals of science education were in a low category because the average of articles citing is less than 10.

Industrial revolution 4.0 requires a person to be literate, as well as science students who have to achieve science literacy through experimental activity. The aim of this research is to develop a collaborative-guided inquiry handbook based on green chemistry vision for general chemistry experiment to promote the students' scientific literacy and communication skills. Preliminary observation found that in general, students faced difficulty to relate chemistry concepts to the experiment they had done through expository model. As a result, they were unable to modify procedures, variables, and chemicals needed to meet green chemistry principles. Developing a collaborative-guided inquiry handbook based on green chemistry vision is expected to cope with the problems as mentioned. This research implemented Borg and Gall's research and development method excluded dissemination phase. Validation from two experts were very valid for the handbook (92,85%), communication skill assessment (94,32%), reflective journal (93,75), and questionnaire (96,88%). The development was also effective because questionnaire performed that more than half of students attained science literacy standard (69,23%) and the vast majority of students (93,7%) agreed that guided experiment laboratory model based on green chemistry vision is useful and they want to apply it for next laboratory activities.

Compost tea is made from compost extracts that contain nutrients needed for plant growth and development. Hydroponics is a planting system that depends on the availability of organic nutrients in the planting medium so that it produces plants that are ready for consumption that are safe and nutritious. This is the basis for providing an understanding of Sustainable Development for high school students in the Adiwiyata program. Adiwiyata is a program that aims to create good conditions for schools to become a place for learning and awareness of school residents (teachers, students, and other workers), to encourage efforts to save the environment and Sustainable Development. The purpose of this study is to increase the understanding of Sustainable Development in high school students in the Adiwiyata program. This study uses one high schools in the Adiwiyata program. Before and after the activity of literacy a hydroponic system using compost tea for safe and nutritious food security and healthy environment, then students were given questions about Sustainable Development. The results showed an increase in understanding of Sustainable Development.

This research is aimed to provide Interview worksheets for Vocational School of Pharmacy Students which have content validity with ethnoscience content so students experience directly how to gain information about medicinal plants used locally as inherited knowledge. Interview worksheets are a form of learning media that can support 21^st century skill inside students. Interview worksheets have to be developed with various interview techniques and need a content validity test in order to be used to reach learning goals. The validity of interview worksheets through content validity must be conducted by experts in science learning field. This content validity is done quantitatively by experts by using Aiken's V. This scoring of interview questions is employed to 26 interview questions with the minimum score is 1 and the maximum score is 5 by 9 validators whose expertise in science learning. Score V gained by using Aiken formula from each question compared to Aiken's content validity table with significance level 5% to decide point validity. Data analysis of interview questions show 15 valid questions of 26 in designed worksheet instruments. The result of Alpha Cronbach's reliability test is 0.99 which means that the reliability level is very strong.

The research aims to calculate the increase of student's Concept Map (CM) scores through the implementation of Problem-Based Learning (PBL). The research is a classroom action. Research procedures include planning, observation, implementation, and reflection. The subjects were 34 X grade students. The data were collected by observation, assessment, interviews, and documentation. CM scores were calculated as a percentage based on expert CM. The research data consisted of the percentage of students' CM scores, performance assessment, the implementation of PBL syntax, interviews, and documentation of the learning process. The validity test used data triangulation. The analysis techniques are through reduction, data presentation, and drawing conclusions. The results show that the percentage of CM scores in the pre-cycle, cycle I, and cycle II, respectively have a range of values of 4.62-20.80%; 11.56-24.25%; and 12.14-30.86% with an average increase in the first cycle is 10.96%, and the second cycle is 4.06%. The increase in the average percentage of CM score is supported by the linear increase in the average components of H, P, B, and E, thus the application of PBL is able to increase the percentage of CM scores based on the linear increase in the average components of H, P, B, and E.

Physics is the most important branch of science, because it contains basic concepts that are also used in other branches of science. In this regard, students need to understand physics well. Instructional media is one way to simplify the process of teaching and learning physics as well as arouse students' achievement. Instructional media has various forms, one of which is multimedia which is developed using information technology-based applications. Lectora Inspire is a multimedia development application that can be used by all groups. This research aims to find out the effectiveness of the instructional media based on Lectora Inspire on student's achievement. The method used is a pre-experimental design consisting of four steps, namely identification of needs, design and development, expert validation, and implementation. The implementation is carried out using the one-group pretest-posttest method in the students of class X IPA-2 MA Al-Asror. The instructional media used has a material feasibility level of 84% so that it gets a very decent category, the level of media feasibility given by the media validator is 80% with a feasible category. The normality test from Shapiro-Wilk method shows that the data is stated to be normal, it means the statistic that suitable to test the data is parametric statistis. T-test paired sample as one of the parametric statistics is choosen to get the significance level from the experiment. The result proves that instructional media based on Lectora Inspire is effective to increase students' achievement.

One of learning outcomes in higher education is the ability to apply logical, innovative, and critical thinking in the science and technology learning. But the instruments to measure it are still few, so this study was aimed to develop critical thinking skills instruments for elementary school pre-service teachers. The mixed-method was used in this research. It consisted of 3 stages, namely, 1) the initial study, 2) design and review, and 3) try out. 122 students were selected as samples. The instrument consisted of 20 items about the Basic Science Concept Development. The items developed according to the indicators of critical thinking skills by Facione. The results showed that all items have a fit in the range of 0.77 - 1.20; mean INFIT MNSQ of 0.99, SD of 0.11; and internal consistency of 0.58. Overall, all items were declared valid and reliable.

Most students have some problems completing their studies on time. Based on the data of Biology Department of FMIPA UNNES, the average of students from 2012 to 2014 who graduated on time only 20.55%. This study would analyze the factors that become constraints in thesis completion. The research design is quantitative methods with ex-post facto strategies. The research sample is students of the Biology Department of the academic year 2012-2015 taken by simple random sampling technique. The data was collected by a questionnaire and processed using the path analysis by SMART PLS software version 2.0. It is found that motivation, administrative factors, and the guidance process contributed to the process of students' thesis completion.

This study aims to analyze the student literacy of students of Biology Education Department FMIPA Universitas Negeri Semarang in because of the implementation of blended learning base on STEM in Ecosystem material. This research method was quantitative research with an experimental approach using "One Shoot Case Study" design. The implementation of blended learning would consider to be successful if accomplished three aspects: (1) the implementation scenario runs well in accordance with the specified time allocation, (2) students reaches the moderate to a high level of technological literacy, (3) the implementation is successful with no severe obstacles while student response it positively. The results exposed that the middle of the second semester could accomplish the implementation of blended learning base on STEM in the Ecosystem material. This research shows that student science literacy has reached mastery learning, with AB (14%), B (72%), and BC (14%). Student technology literacy achieved very high scores. That was the highest one compared to other STEM components: science literacy and mathematics literacy. Student technology literacy ranges from 74.4-93.5, with mastery learning. Students' mathematical literacy ranged from 42-76, with an average of 58.32, including the low category. Furthermore, most of the students expressed positively on the use of the Edmodo application, which contains an introduction and videos. The founded drawback was the technology used was still simple, and the steps in using technology tools in blended learning were incomplete.

Implementation of learning should provides opportunities for students to be able to develop metacognition ability. This study aimed to analyze the influence of Science Digital Storytelling media towards metacognition abilities of students. The study design used is Nonequivalent-Groups pretest-posttest control group. Samples selection are done by random sampling. This study had found that the metacognitive ability of students which consists of five levels of metacognition ability increases. N-gain is at the low category of the control class and was the experimental class. Relations Science Digital Storytelling calculations have been done and the r value obtained is 0, 85 which means that there is a strong relationship between Science Digital Storytelling to metacognition abilities of learners. The test results of the influence of media Science Digital Storytelling is obtained that sig-2 tailed 0.00 <0.05, it can be concluded that the media Science Digital Storytelling has a significant impact on metacognition ability.

This study aims to describe STEM-based Student Worksheets, which facilitate the development of critical and creative thinking skills. Another aim is to test the level of readability, feasibility, and describe the improvement of critical and creative thinking skills after the Student Worksheet is applied. This research uses Research and Development (R&D) method as well as one-group pretest-posttest design. As research subjects were ten high schools in the city of Semarang. The results of the feasibility test indicate the criteria are suitable for learning by obtaining an average of 88.96% which means it is very feasible. In addition, the readability test showed that the worksheets were easily understood with an average of 91.66% and an analysis of improvement in critical and creative thinking skills was found to have high average criteria.

Physics experiments are accompanied by questions that challenge students in learning the topic of the center of gravity which is intended as an alternative solution to foster student interest and reasoning. This research method is classroom action research. Learning is carried out in two cycles in two different identical classes each consisting of 36 students. The improvement in cycle-2 is based on the reflection of learning cycle-1, namely the revision of the use of terms in the student worksheet and the guidelines for carrying out experimental activities to be simpler and more efficient. The implementation in cycle 2 shows that there is no more input from students regarding the unclear work to be done. The results showed that students enjoyed learning (89% cycle-1; 94% cycle-2) and felt more understanding (78% cycle-1; 86% cycle-2), expressing the inspiration they obtained (56% cycle-1; 64% cycle-2). Students stated that they preferred to study the mechanism of physics rather than solving the problem using a formula (58% cycle-1; 94% cycle-2) because they thought it was more useful. The distribution of students' reasoning scores is better than the ability to solve problems, especially students get a lot of difficulties at the problem identification stage.

This study aims to analyze the effectiveness of learning media e-comic earth layer to enhance students' self-directed learning. Method of the research refers to qualitative research approach through qualitative descriptive studies generally are characterized by simultaneous data collection and analysis. The average percentage of Students' self-directed learning values during four times observations is 86.93% which means that the category is very good. It can be concluded that learning media e-comic earth layer effective to enhance students' Self-Directed Learning (SDL).

Assessment in learning is an important aspect to analyze the learning progress. Nowadays, the assessment runs a shifted paradigm from measuring in higher-order thinking aspects to performance assessment. This study aims to develop an assessment instrument based Authentic Scienti_c Inquiry Assessment (ASIA) in measuring the laboratory skills. The laboratory skills consist of_ve skills categories, they are safety skills in the laboratory, experiment management, measuring skills, collecting data, and interpreting skills. From those skills, we derive 20 aspects. We used 4D methods in developing the instruments, define, design, develop, and disseminate. The results of construct validation and content show that the instrument is valid and reliable. We perform the effectivity test and gain the t_count = 25281; t_table = 1,708 with significance level less than 0,05. We also perform a questionnaire for the lecturers and laboratory assistant that shows 85% positive response, 11% of negative response, and 4% of abstance. We can conclude that our instrument is effective to measure the laboratory skills.

Inflation is a critical indicator in showing economic symptoms about prices in a region. The Province of DKI Jakarta is the nation's capital city which plays an important role in the national economy including national inflation. An interesting commodity group is foodstuffs because it contains commodities that play a significant role in inflation in DKI Jakarta. TSClust approach was able to reduce the model by first bundling the commodities together. K-Error is a clustering method that incorporates the error element related to data to be clustered into the clustering step. The purpose of this study is to forecast inflation in Jakarta's agricultural food commodities with the K-Error. Clustering with the K-Error resulted in a lower pseudo F value as the number of clusters increases. Next, the selection of optimum number of clusters was based on a stable pseudo F value, such as the value k = 4 to k = 8. Based on the RMSE value, the optimum number of clusters selected is 5 clusters with unique models. Based on the RMSE value, it can be seen that forecasting at the individual level produced RMSE values that were not significantly different from RMSE level of the cluster for each commodity.

Let G(V, E) be a graph with a non-empty set of vertices V and a set of edges E. A total k-labeling f: V ∪ E → {1,2, ..., k} is called an edge irregular total k-labeling if the weight of each edge is distinct, where the weight of an edge e = xy is wt(e) = f(xy) + f(x) + f(y). Whereas, f is a vertex irregular total k-labeling if the weight wt(x) ≠ wt(y) for two distinct vertices x, y of V(G) where the weight wt(x) = f(x) + ∑_υx∈E(G)f(υx).

The minimum k for which G has an edge irregular total k-labeling is called the total edge irregularity strength (tes) of G. Further, the total vertex irregularity strength (tvs) of G is the minimum k for which G has a vertex irregular total k-labeling. In this paper, we find tes and tvs of heptagon cactus chain graph with pendants and get the results as follows: tes $(C(P{t}_{r}^{3}))=\lceil \frac{8r+2}{3}\rceil$ and tvs $(C(P{t}_{r}^{3}))=\lceil \frac{6r+3}{4}\rceil$.

The aims of this paper wants to analyse the development convergence between regions in Central Java Province. We used the annual data from 2010 until 2016. The regression result show that the absolute convergence have negative sign, it indicate that the poor region could grow faster that the rich region. In other words, there is a possibility of convergence between regions in Central Java Province. From our results, we calculate the speed of convergence among this period, the value amount of 0.007 and 1.053 percent per year, with the implication of the half of life convergence is 66 - 95 years. We suggest that the provincial government of Central Java can prioritize the development programs with focusing on the under-developed regency. This program hoped to reduce income disparities then it will be one of the efforts to reach convergence amongst cities / regencies in Central Java Province.

The spread of infectious diseases has always been of concerns and a threat to public health. It has caused serious problems for the survival of human beings and other species. In epidemiology, mathematical models are the basic conceptual tools used to understand epidemic dynamics and to formulate control strategies. A mathematical model of the transmission dynamics of infectious disease is an important theoretical epidemiology method, which has been used to simulate in analyzing and control of infectious diseases. In this paper, we will discuss about disease model with infection-stage structure, where the period of infection is partitioned into two stages: the acute and the chronic stages. The disease-free equilibrium was locally asymptotically stable when R₀ < 1 and the endemic equilibrium was locally asymptotically stable when R₀ > 1.

The purpose of this research is to design a system to recognize CNV image, DME, Drusen, and Normal, which were produced by Optical Coherence Tomography (OCT). A system would provide a training model, evaluation, and accuracy value. We used the Convolution Neural Network method with default parameter 50 epoch, one stride, 83484 train data images, and learning rate value 0.001 with the help of Python 3.7 software. The examination using epoch variation, stride, number of train data, and learning rate value resulted in different accuracy values. According to epoch variation, the best accuracy was 50 epoch with an accuracy value of 0.99 and loss validation of 0.2034. The best accuracy of stride value variation was one stride with an accuracy value of 0.99 and loss validation of 0.2267. The best accuracy of train data variation was 83484 images with an accuracy value of 0.99 and a loss validation value of 0.2524. The learning rate variation value with the best accuracy was 0.0001, with an accuracy value of 0.992 and validation loss value of 0.2524. According to the result of the research, it was obtained that convolution neural network architecture gain the best model with accuracy value 0.992 according to variation parameter 50 epoch, one stride, 83484 train data images, and learning rate 0.0001.

Interpolation in one of numerical methods to find a value between some data series. Laboratory tests of flavonoid levels in tempe have produced a series of data. These data are pairs of data between isoflavone levels and fat levels, isoflavone levels and protein levels, and also isoflavone levels and carbohydrate levels. However, to analyse the relationship between these data is difficult to do with regression. Lagrange's interpolation is an alternative method to see the relationship between a series of flavonoid data. From the three data can be generated quadratic equations that describe the relationship of the data. From these equations, we can estimate the level of isoflavone if the fat levels is known, as well as the protein levels and the carbohydrate levels.

In this paper, several new mathematical analysis approaches in probabilistic inventory model which incorporate both imperfect quality items existence and lead-free demands are proposed using non-cooperative games. Considered the monopolistic relationship between vendor and buyer in some real inventory problem, the vendor is set to be a leader who determines the Stackelberg's optimal move after observing the optimal responses from the buyer as a follower. Optimum condition using Karush – Khun – Tucker conditions is applied with Stackelberg scheme to get optimum value of the system.

The changes in the structure of the Indonesian economy not only affect the interregional linkages but also the intersectoral linkages, no exception the Central Java Province. This paper aims to calculate and to interpret the interregional effect, especially Central Java Province, to the main island in Indonesia. Using the Interregional Input - Output data for 2005. The study found that the sectors that provide the greatest interregional effect as follows (1) the electricity gas water sector for Central Java and other provinces in Java Islands; (2) the air transport sector for Central Java and Sumatra Islands; (3) the water transport sector for Central Java and Kalimantan, also Central Java and Bali, West Nusa Tenggara and East Nusa Tenggara; (4) oil refining industry sector for Central Java and Sulawesi; (5) animal husbandry and other products sector for Central Java and Maluku - North Maluku - Papua.

This study aimed to improve students' achievement in elementary linear algebra through APOS theory approach. This study is pre-experimental one-shot case study design. The sample were 32 students who participating in the lecture of chemistry mathematics II academic year 2018/2019 at Andalas University. Instrument used in this study was problem solving test in elementary linear algebra which consisted of four item test that measures the ability to solve daily life problem with system of linear equation, determine determinant of the matrix, determine invers of matrix, and determine eigen value and eigen vector of matrix. Descriptive statistics and t-test with α = 0.05 level of significance were used for data analysis. The results show that: (1) APOS theory approach can improve students' achievement in elementary linear algebra significantly and (2) there was no a significant gender gap in students' achievement in elementary linear algebra.

A model of HIV/AIDS epidemic in homogenous community is proposed and analyzed the global dynamic. The model is studied to investigate the existence of equilibria and analyze the global stability. The global dynamic is determined by the basic reproduction ratio that is obtained from the next generation matrix of the model. The endemic equilibrium point is globally asymptotically stable when this ratio exceeds unity, while the disease free equilibrium achieves the global stability when the ratio is less than unity. The simulation results are presented to simulate the evolution of population in the long term

Spatial Empirical Best Linear Unbiased Prediction (SEBLUP) is one of the methods in small area estimation. This method is the development of EBLUP by observing the influence of random spatial correlated areas. One application of this method is the estimation of per capita expenditure in each district/city in Lampung Province. This estimation is based on the existence of additional information on the number of births of the population from each district/city. In this study, the SEBLUP method was applied to the two-level model Normal-Normal and weighting matrix determination based on the type of queen contiguity. Based on the monthly household expenditure data in the Province of Lampung in 2017, Bandarlampung and Metro are areas with high per capita income levels.

This paper exposes two flying vehicles control. The objective of this paper is proposing control design use optimal control approach for flying multi-agent to detect an object. In optimal control approach, beside the dynamical system model, the cost functional is needed. In this paper, the dynamical system model is dynamical system of flying vehicle and the cost functional is the functional which make the vehicles move together to detect the lost object. The scope of this exposition is how to control two flying vehicles move around an object. The two flying vehicles must satisfy the simulation scenarios as follows. Both of the flying vehicles forced do not move far each other and also do not collide each other. Besides mathematical analysis of the model, like controllability and observability of the model, the result of this paper, present the theorem and the proof the cost functional which guarantees that the booth of the vehicles can fly satisfy the scenario. The result also exposes the simulation of controlling two vehicles. The conclusion of this paper states that the optimal control method can be used to solve the problem of control two flying vehicles to detect the lost object.

This article is addressed to show the result of a probabilistic mathematical model implementation in Sewon, Bantul facultative wastewater treatment pond to analyse the performance of the pond. The model was developed in a probabilistic quadratic optimization model and was solved by using probabilistic programming by using deterministic equivalent approach. LINGO 18.0 optimization software package was employed to do the computation. The optimization result was giving the optimal decision value for the wastewater volume that should be processed in the pond in order to gain the best performance and the storing time of the wastewater for each facultative pond. For each facultative pond, the load volume of the wastewater should be 1199.5 kg where the storing time is 13.2 day for the first pond, 13.24 day for the second pond, 25.59 day for the third pond and 30.30 day for the fourth pond. This optimal decision, then, can be used by the decision maker (WWTP operator) in order to optimize the performance of the treatment ponds.

Zika disease began to get the world spotlight when in 2016 around 1-1.5 million people were infected with the Zika virus in Brazil and 4000 babies were born Microcephaly. Indonesia is a region that is potentially attacked by Zika virus outbreaks. This study discusses the mathematical model for the spread of Zika disease in humans is associated with the population of spreading vectors which in this case are mosquitoes. The model used is a deterministic model in the form of a compartment model in sub-population classes. The purpose of this research is to build a mathematical model, analyze the stability point, and arrange a simulation of a mathematical model.

The purpose of this study is to determine the effectiveness of the problem-based learning model with nuances of ethnomatematics on the ability of mathematical literacy. The study was conducted at SMA Negeri 1 Mranggen. The research method used is a combination research method with a concurrent embedded model. The sampling technique uses cluster random sampling. Data collection uses documentation, questionnaires, test results, and interviews. The results showed the model of problem-based learning nuanced effective ethnomatematics against students' mathematical literacy abilities.

This article aims at optimizing Sundanese ethnomatematics learning by improving the modeling and creative thinking abilities of primary school students using teaching materials developed with the Didactic Design Research method. The research subjects involved were first-grade and second-grade students of an Islamic primary school in the city of Serang, Banten with a total of 283 students. The data were obtained using learning obstacles test instrument, Initial Didactic Design and Revised Initial Didactic Design as the instruments. The results of the study show that learning barriers were experienced in the materials of addition and subtraction of numbers. The Initial Didactic Design was revised and developed using Sundanese ethnomathematics learning using endog-endogan and engklek games that resulted in the improvement of primary students' creative thinking, geometry thinking, and algebra.

As one of the competencies that must be possessed in the era of Industry 4.0, creativity also plays an important role for development of mathematics education in the 21st era. This study aims to determine the improvement of students' mathematical creativity in solving Multiple Solution Task (MST) on Challenge Based Learning (CBL) class. The quantitative quasi experimental pretest posttest conducted at SMP Negeri 1 Semarang used a mathematical creativity test adopted MST as a data collection technique and data were analyzed using the t-test hypothesis and gain. The results revealed the improvement of students' mathematical creativity in solving MST after the implementation of CBL and differences in the improvement of students' mathematical creativity where the student's gain of mathematical creativity on CBL (experimental) class was more than the student's gain of the mathematics of the Problem Based Learning (PBL) (control) class. Other findings indicate a difference in achievement of mathematical creativity indicators between the CBL class and PBL class which shows that CBL provides a positive influence to improve each indicator of mathematical creativity.

The purposes of this study were obtained the validity, practicality, and effectiveness of the learning tools that have been integrated teacher stimulus that has been formulated in the design of mathematics learning of fifth grade of elementary school. This development research refers to the 4-D development model developed by Sivasailam et al. (1974) consisted of 4 stages of definition, design, development, and disseminate. This research did not reach the fourth stage. The learning model used is 1) Teams Games Tournament model with the research subjects of Plalangan 1 public elementary school students as many as 44 students with integrated stimulus were problem-posing and the use of manipulative teaching aids, 2) Creative Problem Solving with research subjects Pakintelan 1 public elementary school students with 25 students with stimulus that is integrated were a mathematical game and the use of manipulative. The research instruments were mathematical games, math game discussion sheets, test sheets, problem-posing discussion sheets, tests containing problem posing, student response questionnaire sheets, learning material validation sheets, and learning implementation sheets. The results showed that the learning materials in Plalangan 1 that integrated stimulus problem posing and the use of manipulative were valid, effective, and practical. The results showed that the learning tools in Pakintelan 1 that integrated the stimulus of mathematical games and the use of manipulative were valid, effective, and practical. The further research by applying mathematical stimulus games, problem posing, and the use of manipulative to describe high-level thinking of elementary school students.

Imagination has a valuable role in the process of education for humans. The purpose of the study to determine the role of mathematical imagination to construct an understanding of mathematical concepts. The purpose of this qualitative exploratory study was to analyze students' gestures in understanding algebraic expression. It involved 32 in Junior high school students in Semarang city. Time triangulation was utilized to assure data validity. The results showed that students employed. The results: 1) imagination involved to understand the concept of variables, coefficients or constants is perception visualization that presents the possibility of actions representing a container, representing sum of objects in a container and representing representing sum of objects; 2) imagination in other processes is perception visualization that presents the possibility of action giving examples of algebraic expression, giving examples rather than algebraic expression, and identifying equations. This study yields an important description of misconceptions that are detected through students' imagination.

Students in SLB need to be given a joyful learning. The problems were: (1) How to identify the need for Manipulative Teaching Aids based on Multi-Function Video? (2) How was the analysis of the growth of Joyful Learning in SLB students through the application of Manipulative Teaching Aids based on Multi-Function Video? The goals: (1) To identify the need for Manipulative Teaching Aids based on Multi-Function Video. (2) To foster of Joyful Learning in SLB in mathematics learning through the application of Manipulative Teaching Aids based on Multi-Function Video. The research method is a qualitative approach. Main Activities: (1) Identifying the need for manipulative teaching aids for SLB students (2) analyzing how to grow a Joyful Learning in SLB in mathematics learning, (3) implementing Manipulative Teaching Aids based on Multi-Function Video to support the growth of Joyful Learning in SLB in mathematics learning. (4) conducting interviews with research subjects; data analysis; and triangulation. The results: (1) Identified needs of Manipulative Teaching Aids based on Multi-Function Video for SLB. (2) Joyful Learning grows in SLB through the application of Manipulative Teaching Aids based on Multi-Function Video.

This study aims to: (1) find out the quality of Treffinger learning assisted by scaffolding; (2) find out whether students' abilities in global meta-level algebraic thinking in Treffinger learning assisted by scaffolding reached minimal completeness criteria score; (3) describe the types and causes of student errors in global meta-level algebraic thinking; (4) describe the types of scaffolding that could minimize student errors in global meta-level algebraic thinking. This study used a mixed-method. The results showed that: (1) the quality of Treffinger learning assisted by scaffolding was very good; (2) students' abilities in global meta-level algebraic thinking on Treffinger learning assisted by scaffolding reached minimal completeness criteria score; (3) upper group students tended to make comprehension errors, middle group students tended to make comprehension and process skills errors, lower group students tended to make comprehension, process skills, and encoding error; (4) the type of scaffolding was given to students include the distribution of student worksheets which providing assistance according to the group's level (environmental provisions), explaining, reviewing, and restructuring.

Senior High School (SHS) students need to have advanced mathematical thinking. Its growth can be measured through divergent problem solutions based on the teacher's scaffolding levels. The problems are: (1) How to identify the levels of scaffolding by the teacher to foster advanced mathematical thinking? (2) How to get the results of the analysis to foster of advanced mathematical thinking of SHS students through divergent problem solutions based on the teacher scaffolding levels? The research method was a qualitative approach. The subject of this study was to take 5-6 students of SHS 1 of Ungaran. Research activities: (1) identifying of scaffolding leveling by teachers to foster the advanced mathematical thinking, (2) analyze the growth of advanced mathematical thinking of students of SMAN 1 Ungaran through divergent problem solutions based on the teacher scaffolding levels, (3) conducting of solution analysis of divergent problems based on teacher scaffolding levels; Interview; data analysis; and triangulation. The results: (1) Identified the level of scaffolding by the teacher how to foster advanced mathematical thinking. (2) Obtained the analysis results to foster of advanced mathematical thinking of high school students through divergent problem solutions based on teacher scaffolding leveling. Recommended advice: Teachers need to train their students to be able to work on divergent mathematical problems and provide tiered scaffolding.

Information and communication technologies have become a very powerful means of student engagement in an online learning environment. Google Classroom is an easy-to-use educational application that enables teachers to extend their student learning online. With Google Classroom, teachers can create classes, post assignment, grade and send feedback, and see students' works in real-time. This study aims to investigate the students' perspectives on their engagement in online learning in Google Classroom. An ethnographic case study was employed to explore and observe student activities in a virtual class in Google Classroom. Questionnaire survey and semi-structured interviews were conducted to understand students' perceptions of online learning through Google Classroom. The results showed that Google Classroom has good potential to support students' learning. Students could access the learning resources provided by the teacher at anytime and anywhere. They were also able to construct their knowledge by actively participating in an online discussion forum, and the instructional practices can be performed efficiently. Some challenges that arise included the limited availability of devices, technical issues, and the low level of familiarity of Google Classroom's features, the readiness of students to study independently online. Although challenges arise, the teacher enabled to deal with the issues well.

This study aims to produce a learning trajectory by using the context of Central Java historical building in helping students to understand the concept of one of material in geometry transformation that is reflection. The approach used in this research was Realistic Mathematics Education, in Indonesian version is called by PMRI. Subject of this study was the third grade students of Junior High School 6 Semarang, Central Java, Indonesia. The methodology used was a design research consisting of three phases, namely the preliminary design, the design experiment, and the retrospective analysis. However, this study only shows the results at the design experiment phase, in particular on a pilot experiment. Data collection was done through several techniques, namely: video recordings, photograph, students work result, and students interview during learning process. Student learning activities consist of four activities, namely: observing the video of Central Java historical building, determining, drawing, and finding formula of the shape result of reflection in cartesian coordinate system, determining, drawing, and finding formula of the shape result of reflection by the line which parallel to x-axis and y-axis, and solving problem related to reflection. The results of this study indicate that through a series of activities that have been designed could help to stimulate students understanding of reflection concept by using the context of Central Java historical building.

Mathematics is often seen as universal across cultures. However, there exist differences in symbols, conventions, terminology, and definition used in different cultures. In some situations, the distinctions may be mathematically trivial and have no adverse effect on mathematics instructions. However, in other situations, there may be significant consequences on both mathematical understanding and instructions. This paper examines one such instances in the context of learning and teaching geometry in Indonesia, where the terminology, convention, and definition used caused hurdles in primary teachers' knowledge and understanding of the geometry concepts they teach. Some suggestions to ameliorate these challenges are proposed.

Data analytics skill in statistics is vital because it is immediately related to the accomplishment and writing of students' final projects. The objective of the preliminary study is to describe the data analytics skills of Primary School Teacher Education (PGSD) students and analyze students' needs in their attempts to accomplish and write the final project on time. This qualitative study was conducted at the Department of Primary School Teacher Education, Faculty of Educational Universitas Negeri Semarang, involving students in the sixth semester as the research subject. The techniques of data analysis were the interactive model by Miles and Huberman and Rasch model. The results of this study showed that students in the sixth semester needed innovation in the learning sources for educational statistics course by 95.15%. Data analytics skills of students achieved the average logit model by 0.37. The conclusion of the preliminary study is the majority of students in the sixth semester need innovation in learning sources for educational statistics course and students' skills in analyzing data which are categorized high are only 8%.

The main objective of this research is to develop an ICT-Assisted Preprospec Learning Model. This learning model was developed specifically for learning mathematics and consists of five stages, namely Prepare, Problem Solving, Presentation, Evaluation, Conclusion which at some stages use media based on Information and Communication Technology (ICT). The use of media based on ICT is intended to make learning more effective and efficient. In addition, abstract mathematical characteristics, using a lot of graphics and images and being applied in real life and other scientific disciplines are considered to use ICT-based media in learning. The ICT-Assisted Preprospec Learning Model is expected to improve mathematical problem solving abilities as the heart of mathematics and student's self-renewal capacity. The development of this ICT-assisted Preprospec Learning Model uses the ADDIE Model which consists of 5 stages, namely analysis, design, develop, implement and evaluate. The results of this study indicate that ICT-assisted learning model Preprospec valid and ready to be used for learning.

ASPIRE model is an innovation in mathematics learning that is expected to develop mathematical creative thinking ability. The aspects of the ASPIRE model consists of analysis, scaffolding, project, investigation, reaction and evaluation. The research aims to describe the steps of the ASPIRE model. analysis is the stage where students are analyzed their abilities through filling out questionnaires or online tests so the teacher understands the ability of students and gives them treatment according to their abilities. Scaffolding stage is the provision of assistance, motivation, and direction to students in conducting learning activities. Project stage is implementing learning material in a project assignment. Investigation stage is the process of investigating the results of project tasks and communicating them so that they can be compared with the acquisition of others. Reaction stage is applying of problems related to the material in project task. Evaluation is the stage of testing the ability of students individually. The ASPIRE model is a combination of project-based learning models, problem-based learning, and investigative learning that all three learning models are considered capable of developing mathematical creative thinking ability.

The purpose of this article is to examine the lecturers'efforts to foster students' Mathematical Creativity as part of the 4C Competency to enter the 21^st Century, which students must have. The review of this article is based on the results of the Dissertation research conducted by a qualitative approach. The subject of this research, by taking 6 students of Mathematics Education of FMIPA of UNNES. The main activities of this basic research were: (1) identifying the scaffolding stages by the lecturer to foster students' Mathematical Creativity; (2) analyse the fundamental thinking to foster students' Mathematical Creativity through the provision of open ended problems. The results: (1) The scaffolding stage was identified by the lecturer to foster students' Mathematical Creativity. (2) Obtained the results of an analysis of fundamental thinking to foster the students' Mathematical Creativity through the provision of open ended problems. Suggestion: To prepare the students as teachers candidate in the 21^st century, students need to grow their Mathematical Creativity competencies. Students must also be trained to be able to create of open ended problems based on HOTS.

This study aimed to describe students' critical thinking skills based on mathematical dispositions in Problem-based Learning. This study used descriptive exploratory methods with instruments: test, scale, observation, and documentation. Data was taken from 39 undergraduate students from the mathematics education study program at a university in Central Java. The indicators of critical thinking skills used were abilities in analyzing problems, concluding and giving explanation, evaluating, and choosing problem-solving strategies. The results showed that: (1) there are no students in the negative mathematics disposition group, (2) the enhancement of students' critical thinking skills in Problem-based Learning belongs to the medium category; (3) students in the low positive mathematical disposition group have marginally adequate abilities in analyzing, explaining, and choosing strategies, and adequate abilities in evaluating; (4) students in the moderate positive mathematical disposition group have adequate abilities in explaining, good abilities in analyzing and choosing strategies, and excellent abilities in evaluating; and (5) students in the high positive mathematical disposition group have good abilities in explaining and choosing strategies, excellent abilities in evaluating and analyzing. There was a trend of increasing the achievement of indicators of critical thinking skills based on mathematical disposition in Problem Based Learning.

Industry Revolutionary Era 4.0 requires changes in the organization of learning. Learning is implemented without any concept of time and space. Engineering Mathematics 1 Course has developed MOOC Platform. The aim of this research is to develop assesment instrument and to measure quality of the platform. This assesment instrument is developed by using Plomp Model. Plomp Model consists of five phases, they are; the design phase; the construction phase; test, evaluation, and revision phase; the implementation phase. There are 20 items in this assesment instrument. The 20 items were devided in three indicators. Validation has done by 3 experts. Then the instruments were gived to 100 students. Results from this research consist of 8 items which are valid and reliabel. Value of reliability is questionable.

This study aims to analyze the effectiveness of the Learning Cycle 5E model in developing the mathematical representation ability of Junior High School Students. This study was quantitative. The population was students in Junior High School of grade VIII in Semarang. The sample was taken by a random sampling technique. The data were collected by a test. The data were analyzed by the z-test and t-test. The result showed that (1) students' mathematical representation ability on the Learning Cycle 5E class achieve classical completeness; (2) the average of mathematical representation ability on the Learning Cycle 5E class was higher than on the PBL class; and (3) the proportion of students' mathematical representation ability on the Learning Cycle 5E class was higher than on the PBL class. In other words, the Learning Cycle 5E model was effective in developing the mathematical representation ability of Junior High School Students.

This research aimed to test whether learning with cooperative Jigsaw material geometry with performance assessment achieve mastery learning, test whether the ability of the mathematical representation of students with cooperative learning model Jigsaw material geometry with the assessment of performance is better than the ability of the representation of the students on the model of Discovery Learning, a description of the ability of the mathematical representation students on cooperative learning model Jigsaw with the assessment of student interest. This study is a mixed methods research. The subjects were students of class VIII-A one of junior high school in Kaliwungu, Kendal, Central Java. The data collection method using tests, questionnaires and interviews. The results show that: mathematical representation abilities of students who receive Jigsaw cooperative learning on geometry material with performance assessment fulfill the completeness of learning, mathematical representation abilities of students on geometry material in Jigsaw cooperative learning with performance assessments better than mathematical representation abilities of students on Discovery Learning, and descriptions of mathematical representation abilities students in the Jigsaw cooperative learning with performance assessments in terms of students interest learning that students with high learning interest are able to fulfill indicators of mathematical representation ability is very well, students with learning interest are able to fulfill indicators of mathematical representation ability well and students with low learning interest are less able to fulfill the indicators of mathematical representation ability.