Table of contents

PREFACE

The 2nd FIRST 2018 (Forum in Research, Science, and Technology) International Conference was initiated and organized by State Polytechnic of Sriwijaya in collaboration with University of Cologne, University of Sunderland, International Islamic University Malaysia, and Politeknik Seberang Perai Malaysia. The theme for the 2nd FIRST 2018 International Conference was "Applied Technology for Sustainable Development in Supporting Prosperous Human Existence".

The 2nd FIRST 2018 International Conference facilitated the participants from all over the world to meet face to face to open chances in establishing connection and collaboration among them. It was not only for the researchers in academics, but also in industries and governments. This conference became an effective media to link the researchers from many parts of the world conference, for exchanging, sharing, following up and discussing the results of the latest researches, industries needs, and government regulatory policies.

The 2nd FIRST 2018 International Conference became worthwhile platform for researchers to present their finding in the areas on multidisciplinary of Engineering and Science (Track 1), Computer Science and ICT (Track 2), and Social Science (Track 3). It has also provided an opportunity for the professionals and researchers to learn and share about the latest development and research in those 3 tracks.

List of Organizing Committee is available in this pdf.

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

Nowadays, micro injection molding became one of the technologies for micro manufacture. It is widely used as a cost-effective replication method for mass production of plastic parts. However, one of the challenges for micro molding is the shrinkage which will deteriorate the quality of the micro parts molded. The way to control and minimize the shrinkage is by mean of optimizing the molding parameters. Optimizing process parameter problems are routinely performed in the manufacturing industry, particularly in setting the final optimal process parameters. Final optimal process parameter setting is recognized as one of the most important steps in injection molding for improving the quality of molded products. In this study, Taguchi method was implemented in finding the optimal micro injection molding condition for minimum shrinkage of a micro gear in micro molding experiment. Analysis of Variance (ANOVA) was carried out to determine the most influential factor that contributes towards the shrinkage quality of micro gear. The influential factors that affecting shrinkage are packing time with a contribution of 32.47% and injection speed with a contribution of 22.34%.

Ti6Al4V is one of material that difficult to be machined, and the machining process on thin-walled is also a challenge by the manufacturer. In order to avoid error in thin-walled machining, the FEM simulation using DEFORM-3D is conducted to acquire characteristic along the thin-wall. Dynamic deformation will be presented as stability of thin-wall, which is depicted in movement of the point tracking. As validation in this investigation, the experiment was conducted with 42-degree helical end-mill, which is connected to dynamometer that is obtained the cutting force value. The results showed that the FEM-simulation is failed to approach the experimental results. Some of the suspected reasons are the occurred unpredictable vibration, too small depth of cut.

Low-rank coal is one of the potential natural resources owned by the South Sumatra Province of Indonesia. Research to reduce water content has greatly increased its calorific value. Coal water content can be reduced with low-temperature dry air using dehumidifier and flash dryer equipment with a capacity of 0.30 g per second has been carried out on low-rank coal in South Sumatra, especially for samples of Muara Enim Coal (MEC) coal with 20 mesh and dry air temperature at 70 °C. The results showed an increase in the calorific value of 0.32% and a decrease in water content of 15.92%. The results of the proximate and ultimate analysis have also been carried out at each of the testing stages.

A robot is designed to be a helping tool for the human to work in the dirty, dull and dangerous environment, such as underwater, underground and disaster area. The most suitable type of robot for surveillance is a spherical robot. This type of robot has the ball-shaped, therefore minimize the contact to the ground, reduce friction, and energy consumption. All the components are shielded inside a shell; therefore it is possible to make this robot to be waterproof. One of the applications of this spherical robot is an industrial piping surveillance robot. The robot considered in this study is semi-autonomous where a user moves the robot through user interface installed in an android. The user can control the robot by examining the monitor. The input analysis of how the signal can move the robot is discussed in this paper. To prove the effectiveness of the proposed method, the robot is moved in an experimental setting including a pipe-like tunnel to test it. The robot moved and controlled smoothly, and it can maintain the position of the camera (robot head) always up to ensure the clear vision for the user.

Gas leakage commonly happens in daily life. The leakage can cause many losses and even cause the death. Implementing human and animals in monitoring, checking, and finding the source of leakage can harm their life. The usage of the robot can give many advantages, i.e., it can be programmed easily, it does not feel tired, it does not need much time to be trained, etc. However, to control the robot in navigating to the leakage source is not so Haeasy. In this research, an enhancement of navigation system using two parameters inputs, i.e., distance and concentration of the gas is proposed. A distance fuzzy algorithm and gas fuzzy algorithm is implemented to the robot. The robot can use each parameter depends on the environment and situation that it meets. Both of the algorithms were successful in guiding the robot to move in the correct path. The robot could avoid the obstacles and find the location of the gas leakage.

Quality and consistency of a product have always been the most critical demand in the food paste industry. One of the ways to retain its high standard is through managing consistency. An affordable prototype of the Internet of Things (IoT) based tool used for paste consistency monitoring of various paste property sensors by means of low cost Arduino based embedded system is presented. For a Small and Medium Enterprise (SME), the word 'Affordable' is a critical term. They could not compete with a big enterprise corporation in term of having a high-end monitoring system. Four paste properties were measured: thickness, color, pH and temperature. The status of all parameters was monitored and displayed in two modes: local LCD screen and remote screen from any Wi-Fi based portable gadget. The in-house Arduino based scripting code was developed to integrated the system. The result shows that the developed system could be implemented as a local measurement tool and also be monitored remotely as an IoT based system. The measurement system was validated with the manual measurement. The framework to rescale the project into a bigger scale system was also developed in order to make this system ready for the Industrial 4.0 requirement.

At present, energy needs are increasing almost in all sectors of human life, especially in developing countries. The world's petroleum reserves are depleting, while the need for fuel continues to increase. The use of alternative fuels can be a solution to overcome the problem of energy needs. Biomass is one of several alternative energy sources and has considerable potential to be processed into fuel and easy to obtain. Biomass raw materials can come from plantation or agricultural waste. One of the solid biomass fuels is coconut shell. Coconut shells are biomass derived from coconut plants. The use of coal as fossil fuel is also expected to replace the role of fuel oil. South Sumatra is one of the regions that have a large enough coal reserve potential in Indonesia. Co-gasification is the development of a gasification process that converts two mixtures of solid fuels such as biomass and coal by using air supply from the blower and producing a combustible gas. Therefore, this study aims to determine the effect of air mass flow rates and the fuel mixture ratios of coal and coconut shell on heat energy produced in an updraft gasifier. The research method used was experimented using an updraft type gasifier. This type is the simplest type by producing the output gas from the top. The results show that the fuel mixture ratio of coal and coconut shell as much as 20% : 80% with the air mass flow rate of 4.33 kg/h has the lowest fuel consumption rate of 2.60 kg/h. Furthermore, the fuel mixture ratio of 20% : 80% with air mass flow rate of 12.99 (kg/h) produces the biggest total heat of 1381.46 (kJ). Otherwise, the fuel mixture ratio of 10% : 90% with air mass flow rate of 4.33 (kg/h) produces the smallest total heat of 654.42 (kJ). The results also show that the fuel mixture ratio of 20%: 80% with air mass flow rate of 12.99 (kg/h) yields the highest temperatures in drying, pyrolysis, reduction and oxidation or combustion zones of 125.4 C, 156.2 C, 329.2 C and 589.0 C, respectively.

Indonesia land transportation sector has the largest share of final energy consumption, which is 88%, followed by air transportation 9%, sea transportation 2%, river transportation 1%, and the rest is rail transportation that is still very little. This paper presents policy mix analysis which can contribute for achieving 29% of CO₂ reduction target in Automobiles Sector up to 2030. The result showed that by 2030, automobiles unit in operation (UIO) will achieve 32 million units and emit 114 mega ton CO₂ emission. By introduction of policy mix such as aged vehicle reduction, alternative fuel vehicle (AFV) promotion, Biofuel promotion and low carbon emission vehicle (LCEV) promotion, it can reduce up to 29.6 mega ton, which is around 26% reduction from total.

To determine the criteria for selecting bridges, the ideal support method was required to assist the decision makers. This study was based in the Kudus district and the object of this research was 20 proposals from the Public Works Office for the 2019 bridge handling. From the visual assessment: severe bridge damage (10 bridges), minor bridge damage (3 bridges), medium bridge damage (6 bridges) and bridges in good condition (1 bridge). An imbalance exists between the bridges that need to be maintained and the capacity that can. Depend on existing data, the objective of this study is to analyze the ideal weight main criteria and priority for handling the bridge using the AHP and Promethee II method. A total of 10 respondents were involved in assessing the criteria for The AHP method. A more consistent weighting criteria were produced with a value of 0.31, the ADT weight was 0.19, the number of public and social facilities weight was 0.12, the population weight was 0.15, the area weight was 0.05, the bridge length weight was 0.05, and the bridge width weight was 0.13. The weight of the ideal main criteria is approximately 0.40. Furthermore, the Promethee II method makes the process of priority weighting more dynamic and easier by reducing questionnaire from the AHP method. The main priority was the 8 severely damaged. The highest weight priority was the Klaling – Tanjungrejo 05 bridge.

Indonesia is a country blessed with natural resources potential to be utilized as the renewable energy. Actions should be taken to improve renewable energy based power generation due to the diminishing of conventional fossil fuel and its significant effects on global warming and environmental destruction. Indonesia needs a particular strategy to be able to reach the target of renewable energy utilization by 2025 and 2050. In term of energy consumption, Indonesia is one of the fastest growing countries due to its robust economic development, increasing urbanization and steady population growth. Indonesia uses 40% of the total energy in ASEAN (Association of Southeast Asian Nations) member. Between 2000 and 2014, energy consumption in Indonesia increased by around 65% and is predicted to reach 80% in 2030. This high demand for energy can be fulfilled if all the sectors in Indonesia are hand in hand reaching the targeted goal of renewable energy share. Politeknik Negeri Sriwijaya as a higher education institution should play an active role in supporting government policy in developing renewable energy. This paper discusses POLSRI roles in supporting this policy to develop renewable energy in Palembang and South Sumatra. The literature data is collected from various sources discussing the energy policies of renewable energy. The objectives of this study are to provide the renewable energy development strategies in Indonesia, especially to achieve the target of 23% renewable energy mix in 2025 and 31% in 2050 from the final energy mix following the national energy policy (Government Regulation No.79 of 2014) primarily from the power generation sector.

Plastic bottles (PET) and take-away food containers (PS) waste could be reusable to fix asphalt physical trait that sensitive toward temperature and enhancing the stability of asphalt concrete. Thus it could be used to prevent the damage on rigid pavement such as deformation, corrugation, rutting, and shoving. This research aims to fix asphalt physical trait and to find how much plastic waste percentage (PP+PS) needed so it could replace the asphalt component in Asphalt Concrete (AC-WC). The research is conducted by testing 75 sample with maximum asphalt level of 5.6% and plastic waste percentage ranging from 0%; 2%; 4%; 6%; and 8% compared to asphalt weight. Marshall Test was done in the sample that is soaked in the temperature of 60°C; 70°C; 80°C for 30 minutes and 60°C for 24 hours. Based of Asphalt Pavement Specification (Bina Marga revision 3rd, 2010), hence the percentage of plastic waste that could be used to replace partial asphalt component in Concrete Asphalt (AC-WC) is only 2% of asphalt weight. This percentage is not only fulfilling Marshall characteristic number but also could prevent the further road damage and extremely weatherproof.

The concept of sustainable development is often studied and implemented by cities in the world today. Cities in Indonesia also implement sustainability to realize a sustainable city, in this case in particular colonial cities in Indonesia. Then a study is needed to determine the pattern of colonial cities in Indonesia. In this study the urban pattern was investigated using the Syntax Space approach. The object of research is cities in Indonesia that have been planned by the Dutch colonial. This study was using the Depth Calculation (DC) method to get the similarity ratio. The master plan used in this study is two cities in the Netherlands (Amsterdam and Delft) and three cities in Indonesia (Bandung, Semarang, and Malang). The old city maps calculated its depth and then analysed, the software used was DepthMapX. The results showed that there were similarities between DC in the colonial city master plan of Indonesia planned by Herman Thomas Karsten and the two cities in the Netherlands. The resulting ratio is expected to show how much the difference between the colonial city pattern in Indonesia (CCPI) and cities in the Netherlands. This research is expected to contribute to a better understanding of urban planning in Indonesia in accordance with the Sustainable Urban Form.

Electrical energy is very crucial in whole aspects of our life. No exception with education. Closely related to education, this paper reports the research result concerning with mean, how to overcome power outage in a classroom. Research idea comes up from a situation in which electrical disruption occurs and its purpose is to propose the appropriate solution, namely by creating an apparatus consist of a pair of transmitter and receiver working on the base of radio frequency. There are former articles discussed how to transfer electrical energy by magnetic coupling, but have no invent in radio frequency transmission. It's different to them, the constructed apparatus will transmit the electrical energy through atmosphere media. The concept of radio frequency transmission and electrical generation are background of the creation of the prototype. In order to properly work, the prototype was composed from some modules. The purpose is to make it easier in case of replacement if there are malfunctions. The module consists of transmitter, receiver, multiplier, inverter and converter respectively. Simulation was carried out to optimize performance of the device before real construction. As a conclusion that the device can work well based on the observed output voltage.

Standard wimax have 2 versions : IEEE 802.16-2004 and IEEE 802.16d. This comprehension also supported by Orthogonal Frequency Division multiplexing on Physical Layer. OFDm provide wireless DSL technology where the broadband cable is not available. Wimax 802.16e use Standard OFDMA Technic. It provide the support for nomadic and mobility service also known as WiMAX phone. Wimax is a wireless broadband technology that has an improvement on WI - FI, and UMTS. One of the devices that are needed in the technology is the antenna. The technique used is the MIMO technique. MIMO technique uses multiantenna or more than one antenna from both the transmitter and receiver sides. The design and realization of the antenna in this paper is used for 5G devices in the future that work at a frequency of 5.4 GHz - 5.6 GHz. Antenna simulation shows that the planned working frequency is between 5.4 GHz to 5.6 GHz, has a Return Loss of -20.007 dB, VSWR ≤ 2, which is 1.2216, 414 MHz bandwidth, the gain of 3.898 dB, the impedance of 50.00 Ohm, Omnidirectional radiation pattern. From the design and analysis, this antenna can be used as a 5G technology antenna for the future.

Radio is one of the wireless network system devices that is still widely used today. Transceiver was used because the radio can function as a transmitter and receiver. In this paper, half-wave dipole antenna for radio communication as a transceiver on TDMA Digital Radio was simulated. The antenna was used at 167.5 MHz and radio communication channel. In collecting the data, spectrum analyzer was used as the measuring tool. To analyze the output signal generated by TDMA Digital Radio, the data sample on both measurements. This paper compared the TDMA Digital Radio communication with simulation by using MATLAB. Analyze the Channel Power that has become the output of Spectrum Analyzer, and the measurement of Spectrum Analyzer Measurement was using MATLAB.

High population growth has an impact on increasing the need for sugar cane from year to year. Cintamanis as a sugarcane producer company continues to increase production by reaching the highest production target. In achieving the production target, Cintamanis has a sugarcane milling system consisting of 5 grinding machines that process sequentially. The five machines have three rollers of rollers, the top rollers, the front rollers, and the rear rollers that have a certain distance by the number of cane crops to be processed. The purpose of this research is to optimum milling parameters of sugarcane juice using artificial neural networks. The prediction of this sugarcane milling process uses the input variables of each roll that is found on the milling machine. The approximate procedure begins by calculating each distance between rollers. Then count the amount of sugarcane juice produced. Next, select the input variables that provide a significant correlation to the output variables. Then proceed with designing the optimum network structure and choose the learning rate and momentum. The validation process is performed on the optimum network structure to determine the accuracy level of the sugarcane milling process. The selected backpropagation neural network model is a model with eight inputs, 1 hidden layer (with 8 neurons), and 1 output using binary sigmoid activation in training and linear activation function at the output. Based on testing the maximum number of iterations obtained the lowest MAPE value of 17.85% with the number of iterations 800. Moreover, in the test of learning rate obtained the lowest MAPE value of 17.38% with the value of learning rate 0.4. If the maximum iteration value of 800 and the value of learning rate 0.4 it will result in MAPE value of 16.98%.

Lots of inventions as well as all the uses of technological advances that are very helpful in alleviating human work, especially in the field of industry that cultivate fruit crops with small size. This paper provides a method of accelerating the use of TCS3200 color sensors for color quantization, it was done with various images and showed that the modifications have been able to show that the TCS3200 color sensor is also very competitive as the color quantization of images, both in terms of effectiveness and efficiency. On the other hand, this system will use the pattern by knowing the coffee grouping control system with the wireless signal using Xbee pro module, where the XBee Proo module is to set the remote control with wireless network assisted, so the farmers do not have to bother to controlling from close range. Furthermore, the database will be built for several colors of fruit coffee and the comparison of fruit shape to be made with a control system grouping the fruit of coffee will be done using servo motors, so that when the tool works will be in line with the use of color sensors that can detect the color of the coffee beans.

The absence of a standard reference and limited funds for determining the classification of irrigation maintenance and rehabilitation activities in the Salatiga become an important research nowadays. Budget funds for 14 irrigation areas come different sources. Those funds are limited only to support the maintenance activities, while the rehabilitation activities rely on funds from the provincial and central governments that are not easily to be approved. Therefore, it is necessary to analyse the classification and the priority of irrigation activities. In this research, the grouping analysis employs two assessment criterias, namely; physical condition of irrigation networks and irrigation performance indices. Assessment of irrigation performance indices according to PU Minister's Regulation Number 32/PRT/M/2007 is for technical irrigation status, therefore it is necessary to identify adjustments to existing conditions. The priority analysis of irrigation maintenance activities in this research uses Analytical Network Process (ANP) method. The criterias that are investigated are irrigation performance indices, area width, irrigation status, estimated cost and distance of warehouse to intake. In this research, 4 groups of identifying the classification of irrigation status, i.e. i) technical irrigation, ii) semi-technical irrigation with weir main building, iii) semi-technical irrigation with spring pond main building and iv) simple irrigation, are used. The results of the grouping analysis showed that 11 irrigation areas are included in irrigation maintenance activities. The results of the priority analysis of irrigation maintenance activities from the first to the last priority are; Kedungkopyah, Cengek, Kedawung, Andong, Banyuputih, Siluwing, Sijamban, Bonorejo, Siandran, Sijambe, and Plampeyan. By determining the priority of irrigation maintenance, the budget allocation will be more targetted.

Musi River is the main river with a river length of more than 750 km and the average width of 540 m is still affected by the tides of seawater from the thirteen existing river basin systems and one of the rivers in question is the Sekanak river where changes in the river sekanak this occurs as a result of factors nature and human factors such as the existence of water buoys in river bodies such as pillars, abutments and so forth. The phenomenon that occurs in the Sekanak river is the erosion and sedimentation around the bridge pillars. Erosion and sedimentation is a process that begins with the movement of the soil either floating or in the form of springboard at the bottom of the river, and when the soil becomes a fine particle, some will be left behind, and the other part is carried by the water flow and then into the water body or river to become sediment transport. For that purpose, the research was done by using the physical model approach on standard flume at the laboratory of Faculty of Engineering, Bina Darma University of Palembang. The result of the research showed that sediment movement pattern that happened around the Sekanak river bridge pillar is the plane bed and dune eroded or transition, with flow-down flow type phenomenon, slide flow, horseshoe vortex, and wake vortice while the total bedtime load around the pillar of the river bridge respectively with the formula of MPM tb = 18,44 m³ / day, Einstein and Lane tb = 9910 m³ / day, Frijlink tb = 1030 m³ / day

This paper discusses the wajanbolic reflection antennas on 4G services in urban and sub-urban areas. The antenna uses a reflector from a frying pan with an iron waveguide with its driver a Mobile Wi-Fi (MiFi). Reflector from the antenna is intended to amplify and increase the range of 4G signal coverage, especially in urban areas surrounded by tall buildings and sub-urban areas that have a narrow range of 4G signals. In this research, the strengthening of 4G signal at some point is observed by using WirelessMon software. Increased signal power when using wajanbolic reflection antenna is about 14 dB gain in urban area and 13 dB gain in sub urban area and increase signal gain within a range of a distance of 1 km. The number of access points in urban area is significant enough where there are 12 new hotspots detected, but neither in sub urban area.

Global warming and climate change have been world issue in decades, renewable and green energy technology came as the solutions to overcome it. Renewable energy surely gives many benefits, but one of the disadvantages is harvesting these energy are so depending on climate, weather, seasons and time, therefore hybrid system is one of the solutions of combining these energy to a single system. ATS-Automatic Transfer Switch enclosure can be applied for hybrid photovoltaic (PV) and wind turbine, placing grid ac power and generator set as backup or emergency purposes only. The priority is to use renewable energy as the main power source. Automatic sequential can be programmed into microcontroller for supervision, monitoring and data logging of ATS system by using IoT (Internet Of Things) Technology through GPRS GSM internet gateway. These operations can be performed both locally and remotely using IoT technology for historical analysis of data stored in cloud server.

Demand for energy continues to increase lately due to the increase in the number of people in the world. The technology of wind turbine is currently under development, especially for a low wind speed characteristic. This study was research which was conducted to determine the output of voltage and current produced by the designed wind turbine. The direct current motor was used and worked as a generator of the wind turbine. Data collection of the outputs produced were obtained by the direct analysis using a fan. It was found out that the designed wind turbine could rotate with a low wind speed started from the wind speed of 1.5 – 2.4 m/s. Based on results, it concluded that the designed wind turbine had a potential to be converted into electrical power at a low wind speed area with the cut-in speed of 1.5 m/s.

This research began when the writer conducted a field study to Curup Tenang Bedegung Waterfall, Tanjung Agung District, Muara Enim, South Sumatra. The CurupTenang Bedegung waterfall has the potential to build a micro-hydro Pelton turbine power plant. This study aims to see the flow rate andwater discharge. From this preliminary study, the researcher decided to carry out the design of a micro-hydro Pelton turbine prototype on a mini scale but has optimal rotation and power. In this study, the analyses of the effect of water dischargewere 20, 25, 30, 35, and 40 1/s and the nozzle angle was 50 °, 55 °, 60 ° and 65 ° toward rotation and Pelton turbine power. From the results obtained the higher the water discharge, the turbine rotation is increasing, the highest turbine rotation (691.3 rpm) achieved was at a water discharge of 40 l/s with nozzle angle of 50 °, the higher the water discharge will increase turbine power, the highest turbine power (15.89 watts) was obtained at a water discharge of 40 l/s with a 50 ° of nozzle angle.

The need for energy continues to increase lately due to the increase in the number of people in the world. Solar panel technology is currently being developed, especially to maximize the output voltage of solar panels. This research is a research conducted to determine the output voltage and current produced by the solar panels that are designed. Reflector is used to increase the lighting of solar radiation to solar panels. Data collection from the output voltage generated can be obtained by direct analysis using solar panels without reflectors and solar panels with reflectors. It was found that solar panels with reflectors designed to emit a voltage close to the maximum with an output voltage of 46.81 solar radiation starting from 08.00-17.00. Based on the results, it was concluded that solar panels designed with additional reflectors have the potential to be developed so that they can help maximize the output voltage of the solar panels.

The objectives of this performance test were to determine the angle of nozzle output, the number of a turbine blade and the optimum water discharge to produce the maximum output power from the rotation of Pelton micro-hydro turbine. The performance test was done by using the prototype of Pelton micro-hydro turbine which will later be applied in Sungai Medang Village, Air Hangat Timur district, Kerinci. The waterfall itself has a height of 10 meters with an average water flow discharge of 46.745 m³/s. The performance test itself was carried out with a water flow discharge variation of 20, 25, 30, and 35 Litre/minute, with the output nozzle angle of 50°, 55°, 60° and 65°, with the turbine blade numbers of 4, 8, 12 and 16. Based on the performance test, the maximum output power produced was 15.89 Watt when the turbine rotation was 691.3 rpm, the water flow discharge of 35 litre/minute and the number of turbine blades was 16 with the nozzle output angle of 50°.

Programmable Logic Control (PLC) is an industrial computer specially designed to control the manufacturing process, such as robotics, assembly line, power plant, etc. PLC control program analyzes the input signal to decide the output state according to what has been pre-programmed by the user. This paper discussed the application of PLC as an ATS for on-grid PV system at PLTS Jakabaring which is the biggest PV power plant in Palembang. Therefore, it is interesting to discuss the application of PLC as an ATS in controlling which electric power source used to power Jakabaring Sports City to ensure there is no power outage during Asian Games 2018. The data is taken from July 24-27, 2018 before the event, however, the loads needed to power are more-less the same. The application of PLC as an ATS at PLTS Jakabaring is to automate the switching proses of exporting and importing electrical energy. The energy production data is also compared with the weather forecast to show the effect of sunny days on energy production. Data results show the application of PLC as an ATS for PV system; the ATS hold an essential role for the system due to the system independence of solar irradiance.

Active cooling system technique which flows a thin layer of water on the surface of the PV panels can significantly reduce the panel surface temperature compared to normal use. From experiments conducted in Palembang, Indonesia on August 2018 used two polycrystalline PV panels 100 WP manufactured by Sankelux, can reduce the average surface temperature of PV panels by 18.7°C. The output voltage of the water-cooled PV panels increases by average 1.5 volts when loaded with a 1.5 ohms DC lamp compared to the normal panels. From the experiment, PV panel will work effectively from 8.30 AM to 3.30 PM. Increasing of panel temperature does not significantly affect the output current. The average output power on the water-cooled panel is 31.5 watts, has increased compared to the normal panel 34.2 watts. The overall average output power increase 2.7 watts. The cooling system can also increase the efficiency of the output power. Between 8.30 AM to 3.30 AM, the lowest efficiency enhancement occurred at 9.30 AM is 5.01% and the highest is 13.06 % occurred at 2.30 PM, and overall average efficiency enhancement of output power is 8.6%.

Indonesia is an archipelago country creating a challenging condition for the Indonesian government to distribute electricity evenly among the islands. The Indonesian government has encouraged the citizens to move from fossil fuel to renewable energy and targeted 23% of renewable application of energy mix in 2025 and 31% in 2050 following Government Regulation No. 79 of 2014. Indonesia is blessed with an abundance of sunlight to be harnessed and converted into electricity by a solar plant. One of the alternative applications of the PV system is a floating solar plant. However, the installation of the PV system near the ocean or off-shore endures sea salt effects. This paper presents the effect of sea salt deposition on output and efficiency loss of a PV system. Two modules are applied to simulate; one in a normal condition, another one splashed with sea water imitating the situation endures by the off-shore installed PV module. The case study is currently taking place in Palembang, South Sumatra, Indonesia, and the result of this research will be applied to a fisherman village near Palembang. The output measurement results show there were significant differences in production and efficiency. The average output power difference between the normal condition and salt doused PV module in three days is 1.3778 Watt, and the efficiency difference is 0.948. This number is significant considering the tests were taken for three days. The difference gap can be higher by longer time exposed to salt-containing environments.

Indonesia is very suitable country to use solar energy because Indonesia has a tropical climate and produces daily average energy radiation per unit area and time equivalent to about 4.8 kilo watt/m2, however there are several factors that influence the performance of solar energy, namely PV panel temperature and shadow. Both of these factors are parameters with big influences on PV system behavior due to it greatly affects the system efficiency and output energy. The main effect of increased cell temperature is that on open circuit voltage decreases linearly while cell temperature is increasing. Cell voltage decreases about 2.2 mV per 1°C increase in operating temperature and thus efficiency decreases by about 0.5% for crystalline PV cells. One of the solutions to reduce the effects of excessive heat which results in high temperature in solar PV panels is by installing window film with a distance of 2.5 cm which can produce solar panel output power product with the increase of 23.53% to 24.39% compared to output power product without coating. From the results above, researcher tried to install the window film directly onto the PV solar panel with observation and research methods as well as to analyze the results of the study. The outcome of the study was the temperature was stable at the same conditions while the energy produced was reduced due to direct installation of window film making it as a shadow for PV solar panel

Population increase and economic growth lead to increased demand for world energy. With conventional energy supplies today means there is an increase in the use of fossil energy supplies and increased emissions from gases that can endanger the environment. some renewable sources are available which can be used on a large scale to generate electricity in remote areas where electricity is available. Included in this type include sunlight, geothermal wind, water, and so on. The amount of solar energy potential that can be absorbed depends on the area of the solar cell and the absorption capacity of sunlight. Absorption capacity can be optimized by making a control system for the solar cell's drive that will be flushed in the direction of the sun's motion so that the solar panel cells will absorb sunlight. Researchers focus on how the minimum motor power consumption, obtained from the results of the study occurred at 17:00 at an angle of 690 weight 8 kg voltage of 8.12 current 0.11.

Currently, technological developments in Indonesia are growing very fast, one of which is technology in the field of renewable energy. As a tropical country, Indonesia gets a lot of daylight. National Energy Board data on solar irradiation in Indonesia with irradiation distribution in the Western Region of Indonesia (KBI) around 4.5 kWh / m² / day and in Eastern Indonesia (KTI) around 5.1 kWh / m² / day. We must focus on the development of renewable energy and be a solution to the current energy problems where fossil energy is increasingly depleted of its supplies, especially solar energy with unlimited resources. The problem is if you want to build a solar power plant (PLTS) in a tropical country where the ambient temperature is quite hot if you want to improve the performance of the solar panel you must get the maximum open circuit voltage by maintaining the standard operational temperature of the solar panel. Polycrystalline Sankelux solar panel type SPV 1610-100 with a standard temperature of 25°C will produce a maximum open circuit Voc voltage of 22.94 V. The study was conducted in Palembang between 9:00 a.m. to 3:00 p.m. where the temperature could reach 38°C, the temperature on the surface of the solar panel reached 55°C and solar radiation reached 1447 W / m² at 12:30 a.m. By adding cooling heatsink fan to keep the surface temperature of the solar panel close to the standard operational temperature, the temperature decreased to 15 ° C so we could maximize the open circuit voltage.

Endophytes are endosymbiont organisms that can produce antimicrobial compounds. Media composition is one of the main components to produce industrial compounds. This study investigated the optimal media composition for antimicrobial production by endophytic fungus Sporothrix sp. LBKURCC43. The media were modified by applying composition combination between corn, potato, and sweet potato as carbon sources, and soybean and beef meat as nitrogen sources; incubation times of the fermentation were 5, 10, 15, 20, and 25 days. Antibacterial activity against pathogenic microorganisms (Escherichia coli, Staphylococcus aureus, and Candida albicans) was examined by using the agar diffusion method. A phytochemical test was conducted for determining the highest antibacterial activity. The results showed compounds produced in modified medium MM 03 (potato and soybean) had the highest inhibition zone diameter (8.09 ± 0.62 mm) at 20 days of incubation against E. coli (the ratio between potato and soybean for the medium was 3.60: 0.24). While MM 05 (corn, potato, and soybean at a ratio of 1.8: 1.8: 0.24) indicated the highest inhibition zone against S. aureus (6.03 ± 0.82 mm) at day 20. None of the compound in the modified medium was active against C. albicans. In conclusion, there were varies abilities of endophytic fungus in producing antimicrobial compounds based on their growth medium composition. The highest activity against E. Coli was obtained in the medium consisted of potato and soybean. The phytochemical test indicated the modified medium (MM 05) contained a compound that was categorized as saponin.

Increasing fuel demand has an impact on decreasing fossil energy reserves. One of the solution to solve this problem is by increasing the production of biomass fuels, for example, biodiesel. Biodiesel can be produced from waste cooking oil through transesterification stage that reacts oil molecules with alcohol and catalyst to produce methyl esters. Heating method that can be used is combined of microwaves and high voltage technology. Microwaves technology utilizes wave emission which is absorbed and reflected by the sample to make sample's temperature being higher than surface's temperature of reactor's wall. In the process of producing biodiesel, reaction temperature is one of the several factors that is affected for heating process. From this research, we had optimum reaction temperature to get good quality product is at 60°C with 88.88% yield, 0.88 gr/ml for density, 2.52 cSt for viscosity, 102.5°C for flash point, 0.27% for water content, and 0.33 mg-KOH/gr-sample.

Coconut biodiesel is one of the alternative fuels as a substitute for diesel fuel because it can be produced from renewable energy sources, such as virgin coconut oil (VCO). VCO is one of the most potential ingredients as biodiesel feedstock because of its high oil content. Biodiesel from virgin coconut oil in this study produced a transesterification reaction process using CaO catalyst. This study aims to compare the performance of diesel engines "Dong Feng R-175" using biosolar (B5) and virgin coconut oil biodiesel. This study shows that pure coconut oil biodiesel can be used directly in "Dong Feng R-175" diesel engines. The maximum torque of virgin coconut oil biodiesel is 9.81 Nm at 1200 RPM, and the maximum power produced is 1.33 kW at 1700 RPM with specific fuel consumption (SFC) 0.24 kg / kWh. On average, the thermal efficiency of diesel engines "Dong Feng R-175" using virgin coconut oil biodiesel increased by 33.08% compared to using biodiesel B5.

The development of globalization era which was followed by industry and the economy and also the increasing number of people caused an increase in amount of energy consumption and issues of environmental problems. Therefore, further research is needed on energy conservation in order to reduce non-renewable energy consumption. One of the alternative energy source that can be used as fuel and environmentally friendly is biodiesel. Biodiesel through two stages, the first one is esterification process aims to convert fatty acids from triglycerides in the form of esters. And the second one is transesterification process. It is the conversion of triglycerides or vegetable oils into alkyl esters. In this study coal ash waste and cooking oil as raw material are used for making biodiesel. Coal ash is used as an adsorbent to bind free fatty acids (FFA) toward cooking oil because coal ash has a high silica content. This research was conducted in several stages, namely activation of coal ash, characteristics of coal ash, free fatty acid test (FFA), waste cooking oil adsorption process. Coal ash is activated physically with time and temperature as the variabels. From the activation process, the best coal ash iodine value was obtained at 60 minutes warm up time and 140 °C temperature was 682,173 mg / g. The adsorption process is carried out with a period of 1 gram of adsorbent, 2 grams, and 3 grams. Coal ash can reduce the levels of free fatty acids in used cooking oil by 87.44% in the adsorption process with a time variable of 60 minutes and a temperature of 150°C.

Biodiesel is an alternative fuel for diesel engines produced by the transesterification of vegetable oils or animal fats with short chain alcohols such as methanol. The reaction requires a catalyst which is generally a strong base, thus producing a new chemical compound called methyl ester (Van Gerpen, 2005). One of the most common sources of biodiesel feedstock is CPO (Crude Palm Oil). CPO production in Indonesia is very high at 30.2 million tons in 2016, but CPO prices are low. Biodiesel can be produced using conventional methods, this method is less efficient because of its very slow and inefficient heating resulting from the transfer of energy to materials that depend on the convection currents and the thermal conductivity of the reaction mixture (Refaat and El Sheltawy, 2008) which causes researchers to use new methods of producing Biodiesel, that is by using microwave radiation method. Microwaves are used to emulsify two or more solutions that are difficult to mix (Gunawan, 2003). The advantages of using microwave radiation in the process of making biodiesel are heating faster, more energy efficient, and homogeneous heating. The mol ratio of CPO and methanol is varied to determine the effect of microwave power quality. The power of microwave used is 100,180,300,450 and 600 Watt.

Biodiesel is a promising alternative fuel that can be obtained from vegetable oils or animal fats through transesterification reactions with alcohol. Biodiesel has numerous advantages compared to diesel oil, namely: it is a renewable energy resource, it is not toxic, and it is environmentally friendly because the raw material does not contain sulfur and low emissions. Biodiesel production is inseparable from the availability of raw materials until now the raw materials that meet the needs of production capacity are palm oil (CPO). To overcome this problem, in this study we want to find out how much biodiesel conversion percentage if we use other raw materials such as: CPO oil, corn oil, VCO oil, and waste cooking oil. The analysis used in this study was the analysis of the use of raw materials to the value of biodiesel conversion using the Statistical Process Control (SPC) method. SPC method was used to analyze, manage, control, and improve a product and process using statistics. The objective of this study was to produce high conversion percentage biodiesel and analyze and control the quality of research products. By having this statistical method, it could be found errors in a study or out of control production so that further action can be taken to overcome them. In this study, it was found that the product which was outside of the control limit was biodiesel made from CPO and waste cooking oil. The results of the analysis using cause and effect diagrams could determine the causes of damage in the production process, which come from the factors of workers/humans, production machines, working methods, materials/raw materials and work environment.

Hydrogen is one of promising renewable energy and has potential as an alternative energy source to replace fossil fuel. In its application as a fuel, hydrogen still has deficiencies in terms of storage. If stored in the gaseous form, hydrogen has a very low energy ratio to its volume, so it is necessary to conduct various studies related to methods and materials for storing hydrogen. So far the method of storing hydrogen with the adsorption principle using activated carbon as an adsorbent is very promising because it can lower the pressure in the tank with relatively equal storage capacity. The data collection process is done by gravimetric method and the type of adsorption used is physisorption. The results of this study are indicated hydrogen storage capacity at 2.5 bar pressure using 8.42% activated carbon adsorbent while using zeolite adsorbent by 20.42%. Based on variations in the ratio of the adsorbent mixture obtained the maximum hydrogen storage capacity at a ratio of 2:3 by 4.54%.

Banyuasin Regency, one of the regencies in South Sumatera Province, has abundant natural resources such as coconut plantations that produce wastes. Mostly they are located in Rimau, Muara Telang, Tanjung Lago and Banyuasin II sub-districts. Sri Tiga Village is one of 10 villages in the Sumber Marga Telang which is a division of the Muara Telang sub-district. Currently, the potentially produced wastes are still unmanaged properly. Besides, there are also raising problems in this area, some of the coconut plantations are located in protected forest areas, there are great pressures for occupation from the community around the protected areas for cultivating crops to meet their needs, and this made deforestation and forest degradation unavoidable. One of the solutions can be offered for solving those problems is to increase the income of the forest communities, especially by utilizing the available natural resource in the area such as coconut water waste for producing nata de coco. The abundance of coconut and copra products has not been utilized, with technical assistance in the production of nata de coco, it can increase the income of the people around the forest, and therefore the pressure on the forest occupation can be decreased. Besides the waste, clean water also a problem in this area, in this program the community was also introduced a simple and reliable technology for swamp water filtration.

Industrial liquid waste is one type of waste that can pollute the aquatic environment. For this reason, we need a method that can be used to treat wastewater by electrocoagulation method. Electrocoagulation is a method of coagulation by using electric current through electrochemical events. In this research, the treated wastewater by electrocoagulation method was integrated wastewater. This process was carried out where wastewater was placed in electrochemical cells containing electrodes with dimensions of 15 cm x 15 cm. Parameters of varied are electrode types of aluminum and stainless steel sensors with varied voltages of 6, 9 and 12 volts, and varied processing time of 30, 60, 90, 120 and 150 minutes. The optimum conditions for the aluminum and stainless steel sensors are 12 volt voltages and 150 minutes process time. The effectiveness of electrocoagulation of integrated wastewater using aluminum sensor was TDS 88.96%, 50% TSS, COD 87.96%, BOD5 52.98%, PO4 35.37%, Fe 62.5% and Pb 85% with efficiency of current 78, 91%. The effectiveness of using stainless steel ensemble was TDS 80.27%, TSS 57.5%, COD 88.43%, BOD5 74.86%, PO4 42.20%, Fe 46.86% and Pb 88.57% with efficiency current 81.25%. The research has fulfilled the environmental quality standard.

Potential toxic filamentous cyanobacterium Planktothrix agardhii was detected to be dominated in one of the retention ponds located in Palembang city. It showed persistent domination in the location during observations. This species is known to produce a toxin that potentially causes environmental health problems. Hepatotoxin, microcystin (the cyanotoxin most commonly detected in the freshwater environment) are known types of toxin that is produced by this species. Its potential produced a toxin that is in concern. A preliminary study was conducted to study its potential toxic effect to fish (Cyprinus carpio L.); in this study, four different concentrations of Planktothrix agardhii biomass were used to study its effects to Cyprinus carpio L. gills. The results showed the higher the biomass concentrations (5,4086 x 10⁷ cells/ml), the shorter the length of time for the fishes to be dead (± 2-2 hours 15 minutes). The fishes also showed swimming behavior changes such as swimming direction and excessive mucus excretion. Histopathological changes of the fishes' gills that exposed to Planktothrix agardhii., compared to the un-treated fishes (control) were observed such as edema, lamela gill hyperplasia, and necrosis.

The clay deposit in the coal mining area of Tanjung Enim has a deposit about five times its coal deposit. This clay has not been utilized except as glue on brick briquettes which are relatively small quantities. As a rubber filler, clay can be used, but the silica content is preferred in the clay. Therefore the composition of silica in clay must be known. This study aims to determine the content of silica in the clay contained in the coal mining area of Tanjung Enim. The research begins with clay drying, followed by the fineness of clay grain size to a size of about 10-50 microns. Furthermore, the analysis of the compounds there in is carried out using XRF. The results show that the silica content in the clay is about 53.74 - 75.29% and the highest content is in the Lower D layer 75.29% and followed by the Int B2-C layer 56.87% and Lower C 56.65 %. In general, the compounds in this clay are dominated by SiO₂, Al₂O₃, Fe₂O₃, MgO, TiO₂, and K₂O.

This research is one of the efforts to reduce the impact of CO₂ emissions by cement factory, by making blended cement by mixing Sidoarjo Mud (Lusi) with portland cement. Lusi contains the components of SiO₂, Fe₂O₃, Al₂O₃, CaO and other components very potential to be utilized as an additive to the cement for the manufacture of concrete and building. The Lusi utilization begins by drying the material in the Oven at 100°C for 1-2 hours and refining to 120 mesh. Furthermore, the calcination process in the furnace at a temperature of 700°C, 800°C, 900°C for 1 hour. Calcined ligands are mixed with 10-60% cement (w/w) to cement blended (cement podzoland). The final cement mixture analyzed the chemical composition and the physical properties test comprising the compressive strength test and the setting time, the cement mixed component analysis with XRD showed calcined Lusi could be added 10-60% in the portland cement, the highest compressive strength achieved from 10 %, 18 kgf/cm² and 101,97 kgf/cm² for 3 days and 7 days. While the XRD analysis showed that C₂S, C₃S, C₃A, and C₄AF components averaged 79.28% contained in blended cement.

This study aims to determine the impact of water quality on coal mining on mining areas. Monitoring of wastewater at coal mining area is conducted to determine the level of industry compliance to the quality standard of wastewater discharged to the environment. Monitoring for sampling was conducted on 3 locations of Lahat Subdistrict Puntang Village and Kandis Village (A1 and A2), Merapi Subdistrict Gunung Agung Village (B1 and B2) and Sungai Lilin Subdistrict Mekarjadi Village (C1 and C2). Parameter measurement was carried out in the field and laboratory. The results of the analysis were compared with Decree of Minister of Environment No 113 the year 2003 on the quality standard of coal mining wastewater. Based on the pH measurement of mining activity wastewater was in the range of 3,18 – 5,6, hence the pH had exceeded the required standard of 6 - 9. The Fe, Cu, Zn, Cr, Co, Hg parameters from the analysis were still below the standard of the quality required. Mn and Ni parameters, locations (A1 and A2), (B1 and B2) and C2 analysis result fulfilled the required quality standard of 0,01 Mn and 0,075 Ni, while the location (C2) exceeded the standard of 0,025 Mn and 0,085 Ni. While the concentration of Aluminum (Al) parameter in all locations was above the required standard of 0,05 ppm within the range 0,0557 - 1,219 ppm.

Thermal interface material (TIM) is a solution for handling the heat generated by electronic components such as the central processing unit (CPU). CPU thermal management is important to maintain the performance and endurance of the CPU itself. Thermal interface material the type of thermal grease in the form of a composite is very suitable for use on the CPU. Sodium silicate as a matrix and zinc oxide as fillers has many advantages compared to silicon and metal as the raw material for making thermal grease for CPU which is widely used today. This research aims to produce thermal grease for CPU that has better quality than those on the market today, especially when viewed from the value of thermal resistance. Thermal grease is made by mixing nanosized zinc oxide fillers and sodium silicate matrix with filler concentrations of 14 wt%, 18 wt%, and 20 wt%. Thermal resistance is determined by the application-specific test method against time and compared with thermal grease on the market today. The results showed that thermal grease with sodium silicate matrix and 16 wt% zinc oxide filler had 0.0123 °C/W of thermal resistance which was lower than the market thermal grease.

Direct synthetic dyes are one of the dye types that commonly used in the textile industry. The simple procedure, color variation, and intensity become a good consideration to it. Wastewater that produces contained synthetic organic compounds that caused the reduction of dissolved oxygen level in the water. The tea waste contained high cellulose of 37% that become adsorp media. The purpose of this study was to find out the effect of the initial of dye concentration on adsorption by tea waste and whether the adsorption kinetics followed the Thomas, Yoon-Nelson, and Adam-Bohart, model. The study was carried out by a continuous process with variations in initial concentrations of adsorbate. The adsorption column was buret apparatus with 50 ml of volume. The tea waste placed in the buret. The samples were analyzed by using UV-Vis Spectrophotometer. The research reported that tea waste could be utilized to adsorp direct synthetic dyes. The increases of initial concentration will obtain higher dye adsorption. The tea waste adsorbent removed 46.72-51.44 % of dye with experimental of adsorption capacity was 41.085 to 147.814 mg/g. The kinetic model of this experiment followed Thomas model with R² values ranging from 0.892 to 0.970, and the adsorption capacity was in the range 191.78-577.686 mg/g.

Indigenous bacteria was isolated from POME, and the bacteria was applied to degrade oil, protein, and cellulose in an anaerobic condition and to produce biogas from artificial substrates, namely: oil, protein, and cellulose. Degradation process of the substrate was conducted in a bioreactor with degradation time of 3, 6, 9, 12 and 15 day. Stenotrophomonas rhizophila strain e-p10 as lipolytic bacteria dan Bacillus toyonensis strain BCT-711 as proteolytic and celulolytic bacteria were used in the degradation process. Specific growth rate, µ = 4.57 day⁻¹ was obtained for lipolytic bacteria; 4.73 day⁻¹ for proteolytic and 4.42 day⁻¹ for cellulolytic bacteria. The optimum time for degradation of the substrate was 12 days. The production of methane achieves 47.04 % for lipolytic bacteria, 19.67% for proteolytic and 51.40% for cellulolytic bacteria.

In order to obtain bioplastics product form Musa paradisica formatyca concentrate, sorbitol and glycerol plasticizer substance is added. The purpose is to make bioplastics produces more flexible and more elastic. This study is conducted to determine the effect of the composition of sorbitol and glycerol plasticizer so that an optimal biodegradable plastics be able to obtain. The other ingredients utilized are acetic acid, chitosan, and aquedest. The method used for this study is mixing 100 ml of the essence of Musa paradisica formatypica, 0.7% chitosan (% v / v), 0.5% acetic acid (% v / v), 5 grams of cornstarch with plasticiser (0%, 1%, 2 %, 3%, 4%, 5% sorbitol and 0%, 1%, 2%, 3%, 4%, 5% glycerol) of the volume of essence of banana peel, then heated to 90ºC with a stirring speed of 300 rpm for 30 minutes. The results obtained in the form of thin sheets of bioplastic were tested mechanically in the form of tensile strength and percent elongation. Based on the analysis of tensile strength and elongation percent technique, it was found that bioplastics were close to the standard, i.e., in the sample 3% glycerol (% v / v) with a tensile strength of 46.4201 Mpa and percent elongation of 15.15152% and a sample of 5% sorbitol (% v / v) tensile strength 31.4228 MPa and elongation percentage 15.15152%.

One of the methods for air separation to get nitrogen gas is using the Pressure Swing Adsorption (PSA). Adsorption is a separation process to adsorb oxygen and release nitrogen as a product. This research aims to study the equilibrium and kinetics that occur in the oxygen adsorption using carbon sieve molecular (CMS) as an adsorbent. Air flowed through the compressor to PSA, air pressure (4 - 7 bar) and absorption time (3 - 9 minutes) were observed. The results showed that the higher pressure, the lower nitrogen purity. The highest nitrogen purity is 96.2% that produced at 4 bar pressure in 7 minutes. The adsorption equilibrium fits well to Temkin isotherm with R² = 0.9938, Temkin isotherm constant (b) = 63.203 × 10³, Temkin isotherm equilibrium binding constant (A) = 1.00 L/g, and Constant related to heat of sorption (B) = 0.03 92 J/mol. First order pseudo model kinetics is suitable for oxygen adsorption processes. The value of adsorption rate constants are vary around (4, 5, 6 and 7 bar pressure) : 0.8089 min⁻¹, 0.203 min⁻¹, 0.3476 min⁻¹, and 0.6668 min⁻¹ with R² = 1.

O-rings are a primary component made from polymeric materials in most diesel engine systems. For oil-fuelled operations, O-rings tend to degrade after exposure to fuel in certain operating condition and periods. Degradation of O-rings can cause engine leakage. This study is intended to test the O-rings material which contacted with biodiesel in dynamic flow by considering the potential deterioration caused. The use of biodiesel may contribute to accelerating deterioration of O-rings. The boiler fuel system was duplicated in this test, where the biodiesel used was palm oil based. The O-rings tested are made of materials of Fluorocarbon elastomer (FKM), Nitrile Rubber (NR) and Silicone Rubber (SR). The effects on O-rings were observed on changes in mass, volume, and thickness. The material compatibility is indicated by elongation, swelling and chemical resistance of elastomers with various fuel flow rates. The fuel flow with high volumetric rate tends to damage the O-rings faster as effected on the immersion test. FKM-Viton performed as materials with the best physical and chemical resistance. Dynamic fuel flow in the engine system showed that SR is deteriorated faster than NBR and FKM. The resistance of O-ring material to fuel in the system is not linearly influenced by the amount of biodiesel in the fuel.

Biodiesel derived from microalgae has been considered as one of the substitutes for fossil fuels. There are many microalgae with hight lipid content that can use for the raw material of biodiesel. Microalgae Spirulina plantesis in the fast few years has been developed to become biodiesel feedstock, previously this microalga was widely used in food supplements. The purpose of this research is to study the growth of microalgae in lab scale cultivation, to extract lipids by maceration, soxlet, and osmotic methods and analyze the biodiesel obtained from the transesterification process. Cultivation was carried out in laboratorium scale with bright dark lighting conditions (12:12 hours), using Walne medium, pH of 7-10 and salinity of 25-30 ppt. Cell density was observed using a microscope and was calculated using a hemasitometer. From the results of the study at the cultivation stage, it was found that the optimum pH for the growth of microalgae Spirulina Platensis was at pH of 9 and lipids obtained from maceration, osmotic and soclet extraction methods are 5.5%, 0.6%, and 9%. Biodiesel which had the highest calorific value was obtained through extraction using the maceration method with a caloric value of 11200 cal/gram and density 0,875 gram/cc.

The bark of Acacia mangium is lignocellulosic biomass from waste pulp which can be recovered by means of hydrolyse to produce simple sugar called glucose. To produce glucose, there are two stages of the process performed is process using solvent delignification NaOH and KOH. The parameters analyzed were the biomass with a solvent ratio (1:6, 1:8, 1:10, 1:12). The second stage cellulose is then hydrolyzed to see the influence of sulfuric acid concentration of the resulting glucose content (0.1; 0.25; 0.40; 0.55% (v/v)).Lignin removal efficiency using NaOH and KOH solvent that is almost equal to 62.39%. Decrease hemicellulose using KOH solvent (36%) are more efficient than solvent only 29.3% NaOH. Efficiency increased levels of cellulose using NaOH or KOH solvent almost equal approximately 85.5%, but with KOH the lower alkaline properties provide a more stable rise. Solvent delignification process with NaOH provide large enough glucose content at a ratio of 1: 6 and 1: 8 with sulfuric acid concentration in the range of 0.1 to 0.4 and 0.5% v/v. Increased glucose content in the solvent of NaOH at a ratio of 1:6 reached 69.88 ppm for sulfuric acid concentration of 0.55% v/v, whereas the content of glucose degradation products of cellulose with delignification process using KOH solvent is in the range of 3.25 ppm to 77.67 ppm. The highest value is produced by the hydrolysis of cellulose to the sulfuric acid concentration of 0.4% v/v, and the KOH solvent ratio is 1:10. The higher the ratio, the lower the KOH solvent content of glucose produced.

The purpose of this study was to determine the optimal operating conditions in the process of making oxidized starch. Tapioca oxidizing reaction is using sodium hypochlorite compound. The fixed variable is the weight of cassava starch as much as 20 gr, 50 ml of 0.01 N sodium hypochlorite and condition of reaction is at room temperature. Variable changes are pH 6, 7, 8, 9 and reaction time 30, 60, 90, 120 minutes. Characteristics of oxidized starch were a carboxyl group, swelling power, and solubility analysis. The application of oxidized sago starch is as an adhesive in the pulping process. From the results of the study it can be seen that as the reaction time increases, carboxyl groups increase, decrease in swelling power and increase in solubility. Whereas along with the increase in pH of the solution there was an increase to pH 8 but then decreased at pH 9 and reaction time 90 minutes.

Leachate water is a very dangerous liquid due to its organic and inorganic content that can pollute water body around the landfill, hence treatment is needed. Electrocoagulation is one of the methods that can be used. The research aims to determine a characteristic of leachate water at TPA Sukawinatan (COD, pH, BOD₅, TSS, and Cd content), the effect to electrodes distance (aluminium anode and iron cathode) and optimum time of treatment Leachate Water using electrocoagulation type MP-P (MonoPolar-Parallel) method. The electrical potential was set at 12 volts and time variations of 30,60,75, 90 and 120 minutes and electrodes distances of 6, 7 and 8 cm. The result obtained shown that COD decreased to 529.20 mg/L, pH became 8.34, BOD₅ decreased to 17.6 mg/L, TSS became 108 mg/L and <0.0015 mg/L of Cd content. The optimum electrodes distance to treat leachate water was found 8 cm in 120 minutes fo electrocoagulation type MP-P.

Air is one of the essential needs that used by living things either directly or indirectly. The demand for nitrogen in the chemical industry in the world continues to increase every year, especially in the fertilizer industry. In the industry, nitrogen can be used to manufacture ammonia or start tipping on an ammonia plant, also to protect materials from bacterial and fungal disorders. In addition, in the field of nitrogen transport is often to add to vehicle restrictions Pump the wheels using nitrogen will make the wheels more durable and the wheel rim is not easily damaged. Based on the amount of demand for nitrogen gas, the nitrogen production process is conducted by Pressure Swing Adsorption (PSA) method. The adsorption capacity of the adsorbent depends on the temperature, pressure, type of adsorbent and characteristic of the adsorbent. In this case, the temperature at the process is one of the most important parameters, the temperature, in this case, is the temperature of the adsorbate. When a gas or adsorbate molecule is attached to the surface of the adsorbent, there will be an energy release called an exothermic event. The reduced temperature will increase the amount of adsorbate adsorbed and also for the opposite event. Because of that, it is needed an air conditioner in the form of a cooler that serves to maintain and reduce the air temperature of the feed (adsorbate) does not experience an increase when operating conditions take place. The highest nitrogen purity was 95.7%, at 7 bar PSA, cooling fluid flow rate 35.4 m/s, daily cooling 41.58%, and air feed temperature 30.7°C.

The depletion of petroleum reserves, the price of fuel oil (BBM) which tends to increase, and environmental safety reasons encourage the search for other materials to be made as raw materials for making bioethanol. One of the most potent ingredients as raw material for making bioethanol is lignocellulosic biomass. Lignocellulosic biomass consists of three main components, namely: lignin, cellulose, and hemicellulose. Cellulose and hemicellulose are sugar polymers which can be broken down / hydrolyzed to produce sugar and then fermented into bioethanol. One of the lignocellulosic biomass that can be used as a substrate for bioethanol production is peat. This study will review the effect of the delignification process and hydrolysis of the yield percent of ethanol produced in bioethanol production from peat soil.

Short cooking time produces a small amount of cellulose in the pulp production, while a long cooking time causes the cellulose content in the pulp to become damaged. Cooking temperature that is too low produces a small amount of cellulose in the pulp, while the cooking temperature that is too high will damage the cellulose content in the pulp. The faster the stirring the more lignin apart from cellulose, the lower the cellulose content due to weakening of the saccharide bond in cellulose, the lower the yield produced because the product dissolves more and more. In this study, the parameters chosen were cooking time diversity (40, 50, 60, 70, and 80 minutes), cooking temperature (80, 90, 100, 110 and 120 °C), and stirring speed (20, 40, 60, 80 and 100 rpm). Analysis of water, ash, cellulose, lignin content and tensile strength was carried out as pulp quality testing in this study. It turns out that from the results of the study, the optimum value was obtained at 90 °C cooking temperature with pulp yield of 64.09%, water content of 16%, ash content of 2.5%, cellulose content of 73%, lignin content of 8.5%, and tensile strength 1.96 kN/m².

Empty Palm bunches is the raw materials in the making of particle board with the adhesive of Liquid Guava Rod Bark, The Hot Pressing process at 16 Mpa and temperature 150oC. The particle board was created with a size of 20 x 15 x 2 cm with a target density of 0.7 g/cm³. This research aims to know the characteristics of particle board using adhesive liquida guava rod bark on the empty Palm bunches and performed tests to find out the quality of particle board with reference to standard JIS A 5908-2003. The result showed an adhesive has a real effect on fiber moisture content particle board and influential real pressure against temperature MOR (Modulus of Rupture). From the testing that was performed the particle board have 0,837 gr/cm3 density, moisture content, and strong 8,67% hold screws 18.25 kg at the rate of 20% of the adhesive that has been standard JIS A 5908-2003 while the absorption of water, development of thick, elastic modulus, modulus of a broken and sticky firmness has not met internal standards.

Automatic seeder based android in laboratory scale aims to helping the farmers in the seeding process before planting in field. This machine also automatically treats the seeds regularly by ordering the program through android to simplify the use of the tool. So ease farmers in terms of energy and time spent. This tool has an electric motor using a microcontroller. System as a driver with the help of android that will run the program. The seeding process is carried out in 2 stages: first spreading the rice seeds and second watering the rice seeds, then regularly will take care of the rice seeds to develop. The process of designing machine applying CAD software while for fabrication use of drilling machine soldering machine, 3D printing and hand tools. After making the prototype of this tool is tested in laboratory and the result of this tool can spread rice seeds as much as 12 grams with time of 1 second.

This study aims to produce a valid and effective mathematics instructional package use creative problem solving (CPS) models for improving adaptive reasoning ability and the creative thinking ability in mathematics. The instructional package development model used was to modify the Borg and Gall model, and refer to the Dick and Carrey instructional design model. The sample in this research was Chemical Engineering students at State Polytechnic of Sriwijaya. Data collection instruments used were expert validation sheets and tests of adaptive reasoning ability and tests of creative thinking ability in mathematics. The data collected is in the form of data about the quality of the product being developed, namely validity and effectiveness, as well as potential effects of the use of learning packages that have been produced. The instructional package framework developed consists of an introduction, problem exploration, concept strengthening, information extraction, problem solving, concept development, summary, and evaluation, emphasizing freedom of opinion and material developed based on CPS learning. The results showed that the instructional package developed had met the criteria of expected validity and effectiveness. The results of the study using the instructional package showed an increase in creative thinking abilities and adaptive reasoning abilities.

The main goal of this research is to determine the effect of banana peels pectin on the characteristics of biodegradable film plastic, especially thickness, water resistance, tensile strength, and elongation. With the addition of citric acid, extract of banana peel starch as filler, and glycerol as plasticizer. The results showed that the use of citric acid could reduce the browning effect of pectin with the characteristics of water content of 11.56%, ash content of 3.060%, low methoxyl content of 3.906% (<7%), characteristics of the best biodegradable plastic film on the addition of pectin 5 grams with thickness characteristics 0.00387 cm, water resistance 63.63%, tensile strength of 10.5620 MPa, and elongation of 58.33%.

The world has seen in recent years a somewhat social communication among people in the virtual space. In addition, it has had a great influence on political and social conditions, especially in the Middle East and North Africa. It was necessary to take advantage of the potential of these technologies in the development of the services provided by the government to its citizen. The governments in the region began to adopt the use of social networking tools, concepts of community participation and collective solutions with the aim to support the countries' development sustainability. As many countries have adopted the concepts of citizen involvement as a key element in the provision of government services, this paper presents a framework on how to use the social network to upgrade and optimize the government services. Sudan is selected as a case study as one of the least developed countries in the region where E-Government application is just beginning.

The results of testing the system when the active sensor detects 0 ppm CO₂ gaseous gas, 440 ppm CO₂ and 0 ppm CH₄ air condition "safe" with a not rotate exhaust fan output. In the active sensor, it detects CO 500 ppm gas, 410 ppm CO₂ and 0 ppm CH₄ "Danger" air condition with speed rotating exhaust fan output. While the active sensor detects CO 0 ppm gas, 308 ppm CO₂ and 540 ppm CH₄ "Very Danger" air condition with high exhaust fan spinning output. In conclusion, this study shows that the results of testing the system when the active sensor detects 0 ppm CO₂ gaseous gas, 440 ppm CO₂ and 0 ppm CH₄ air condition "safe" with a not rotate exhaust fan output. In the active sensor, it detects CO 500 ppm gas, 410 ppm CO₂ and 0 ppm CH₄ "Danger" air condition with speed rotating exhaust fan output. While the active sensor detects CO 0 ppm gas, 308 ppm CO₂ and 540 ppm CH₄ "Very Danger" air condition with high exhaust fan spinning output.

Changes in weather and climate conditions have consequences on various sectors of life and greatly affect the activities of human life. Therefore we need a system that can detect weather conditions based on cloud imagery. Finding methods to detect weather conditions at one time with image processing is a new innovation that appears in current weather modeling. This is driven by the high need of various parties to conduct research in detecting a condition carefully and without having to observe it directly. In this study a climate condition classification system will be designed based on cloud imagery using the Hybrid method, namely PCA + LDA. All cloud imagery will be grayscale then feature extraction and cloud classification process using Euclidean Distance. Based on the tests carried out, the system produces an accuracy rate of 96%. The predicted weather conditions are bright, cloudy, and rainy conditions.

Health service place in Palembang consists of puskesmas, hospitals, health clinics, and pharmacies. People in Palembang get information about health service place through information about the surrounding community, health service institutions and websites that are displayed separately. Geographic Information System (GIS) is used to provide complete information about health service place in Palembang. GIS technology can display spatial data such as a digital map of health service location consisting of puskesmas, hospitals, pharmacies, and health clinics. GIS produces web based system that can be accessed online and quickly. GIS applies google map API technology with prototype method as a system development technique.

The utilization of the internet in education world is able to facilitate the increased intensity of educational activities. The lecture process that was previously only in a classroom, is currently undergoing a transition. A mix of teaching methods and materials of direct learning or face-to-face in class and e-learning by online methodologies in formal education as called blended Learning has been popular in educational practice. Regarding to the adequacy of mixed learning have prompted an expanding number of concentrates on this theme. The objective of this paper are to review about characteristics in Blended Learning and evaluation about the issues and challenges in it. There are three databases found for this studies which are Science Direct, IEEExplore and Google Scholar. After the databases filtered, there are 19 papers selected for this review as there are appropriate to the criteria needed. This studies aims to bring the knowledge for developer or research groups about Blended Learning and as intructional media in Learning for manage, create, and deliver courses.

Ant Colony is a methodology produced by observing ants. In this algorithm, ants as agents assigned to find solutions to an optimization problem, like to find the optimal solution on Traveling Salesman Problem (TSP). Therefore, the research will apply ant colony algorithm to search the shortest path of tourism in Palembang City, covering tourist destinations, culinary, hotels and handicrafts. The results of this study, will provide ease of tourists in accessing tourist destination information and information about travel routes easily via mobile applications with android operating system and use of Google Maps API.

The tourism industry potentially produces enormous economic benefits for not only the local area but also the country. In this case, South Sumatra Province is one of the tourist destinations in Indonesia which has plentiful tourism site to be developed. Therefore, an application is needed to support and develop local tourist site. E-Tourism is a solution in providing information for tourist, and its implementation of E-tourism in South Sumatra province is implemented through website and smartphone with Android and iOS operating systems.

The purpose of this research was to design a database system scheme for the "Waterfall Tour South Sumatra" website service guide. The database design method on this Website used Database Life Cycle (DBLC). The variable in this research was the database design service guide "Waterfall Tour South Sumatra" with a relational data model consisting of 4 (four) tables namely admin table, waterfall table, news table, testimony tables using conceptual schemes, logical schemes, and physical schemes.

Expert systems are a branch of artificial intelligence, namely by storing expertise from human experts into computers and storing knowledge in computers so that users can consult like human experts. Expert systems are now being applied to diagnosing diseases in humans, animals, and plants. With this system users becoming more practical and knowledgeable in diagnosing natural diseases. a good expert system must provide a good and accurate result so that it can be use. Factors that influence system accuracies such as classification methods, input analysis, and technology are considered for the development of a good expert system to serve it functions as an expert. The purpose of this paper is to analyze these factors for the development of a better system.

Pedado Village has several SMEs that are not yet well known by the wider community. These SMEs produce various products such as flannel handicrafts, Palembang mattress, and oyster mushrooms. Even the marketing of this product is still done manually, that is, the buyer comes directly to the seller to buy the product. This study aimed to build a website that can promote Pedado Village in general and the products produced by SMEs in particular. The website could also be used for online buying and selling transactions. The method used in website development is the Spiral method. The research results were a website that could be used to display information in the form of Pedado Village profile, SMEs and activities in Pedado Village, products produced by these SMEs, and the purchase of these products online. The use of the Spiral method was limited to the initial evaluation stage, which was testing the system using the blackbox method, with the results of the website could be used according to its function.

The purpose of this study is to provide information about areas that get raskin aid according to the variables specified. The variables consist of income, housing, clothing, food and education. The supporting variables are indicators in determining the decision making received, considered or rejected. The Decision Making uses the FUZZY-AHP method which is implemented using Geographic Information System based applications. The map used is Maps Android API. The output produced is the mapping of the raskin aid area.

This research is entitled Application Design for Lecturer Advancement in Sriwijaya State Polytechnic Palembang. The purpose of this study was to design an application for promotion of lecturers at Sriwijaya State Polytechnic so that data processing can run faster and more dynamically and design employee applications that are based on PHP and use MySql databases. Data collected by interview, observation and literature study.

Each regency/city in South Sumatra Province would be synergized to advance the tourism sector in accordance with the South Sumatra Tourism Development Master Plan for 2016-2025. The problems that exist in the tourism industry in South Sumatra province, especially Palembang City was the difficulty in quality control (Quality Control) because the available performance data and information was incomplete and integrated. The purpose of this study was to produce Quality Control System (QCS) Website of Tourism Industry Sector in Palembang City. This study used the Extreme Programming method. The result of this study was the website http://www.qcs-pariwisata.com, which provided four types of access rights, namely, super admin (overall website manager) or in this case the tourism agency, tourism business owner (this access is obtained if the user has registered and paid the registration fee to be able to post tourist data that is owned), registered visitors, and unregistered visitors.

Parking is becoming a problem, especially during rush hour. This is an effect of increasing number of private cars that demand of parking space to follow increase. In order to anticipate this key issue of parking, then the smart parking system has been developed. Advancement of smart parking has been a key concern to produce an application system with high performance, flexibility, and scalability in emerging technologies that can provide information about parking in real-time. The empirical study in this area has conducted various parking system reservations, monitoring, and guidance systems that can make parking process easier. This review emphasizes the aim to give a narrative review of the papers in our pool of papers to prove the evidence and provide an application technology advancement to produce a real-time parking system. The review has included 22 papers from our pool of papers which has examined, which are analyzed from used system technology to build the smart parking application. The narrative review was carried out to exposes the existing application parking and compared to parking application that have implemented a MEAN stack. Search terms used in the literature review are applications that have been elaborate a study of smart parking application as a key concern of this study. Synthesis of the papers on the pool has suggested that there is an optimistic reason that a MEAN stack approach might be effective to produce a real-time application high performance, flexibility, and scalability technologies from a smart parking application.