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This study aims to determine the effect of the geometry shape of the copper material heat sink fins on the surface temperature distribution of the heat sink. The material used in this research is pure copper, the shape of the heat sink fins is made rippled with the addition of the number of fins 5, 6, and 7 and the input temperature is varied from 40 C to 80 C with airflow variations from 0.2 m/s to 1 m/s. The first step is to create a heat sink design with Autodesk Inventor. Then the plan is simulated with Autodesk CFD to solve the continuity, momentum, turbulence, and energy equations. Based on the method that has been carried out, it is found that the addition of variations in the number of fins affects the decrease in surface temperature. The highest temperature drop on fin 5 ripples is 24.1 C. The heat energy transfer rate increased by 0.4657 W. The convection heat transfer coefficient increased by 3.47 W/m²C. Nusselt number shows an increase of 271. Fin performance has increased efficiency by 63.4 %, and effectiveness by 1.61. The results of this study are expected to provide practical alternatives that can be widely adopted on a heatsink plate that is very promising for future thermal developments.

Electroless plating on Acrylonitrile Butadiene Styrene (ABS) is a metallization process that involves a reduction and oxidation reaction between the nickel source and the substrate material. The purpose of this research is to determine the ability of nickel deposition in the nickel electroless plating process with a specific etching time variation. This nickel electroless procedure begins with a chromic acid etching process that can last anywhere from 15 to 55 minutes and is useful for increasing roughness and creating submicroscopic cavities. After the etching process is finished, the surface roughness test is performed with a Mitutoyo SJ-210. Additionally, the activation step is carried out for 5 minutes in order for the polymer to become a conductor, allowing the plating process to proceed. The electroless plating process was then carried out for 55 and 75 minutes, with the goal of depositing nickel metal on the ABS surface. The coating results were analyzed using Fourier Transform Infrared (FTIR) spectroscopy IRSpirit/ATR-S serial No. A224158/Shimadzu to determine the functional groups formed both before and after the coating process, X-Ray Diffraction (XRD) to determine the character of the crystal structure, and phase analysis of a solid material using PANalytical type E'xpert Pro, To determine the surface morphology, the Zeiss EVO MA 10 was used to perform scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) at 1000x magnification. The test findings demonstrate that, based on a range of investigations, etching variations of 15,25,35,45, and 55 minutes etching time 55 minutes are the best nickel deposited substrates, as evidenced by EDS data, where this treatment has the largest weight fraction of nickel. As a result, the longer the etching period, the rougher the surface becomes, affecting the capacity of nickel deposition to increase. Furthermore, it can be demonstrated in this investigation that the nickel deposited is in an amorphous form.

Biogas adalah salah satu energi alternatif yang mempunyai nilai ekonomisnya besar teruntuk masyarakat pedesaan. Dalam prakteknya kandungan CH4 biogas menjadi bagian terpenting untuk proses konversi energi namun zat pengotor berupa karbondioksida yang menurunkan nilai kalor masih besar. Sehingga diperlukan upaya untuk menurunkan CO2 dengan proses purifikasi. Tujuan penelitian ini untuk mendapatkan cara purifikasi yang meningkatkan kualitas biogas dengan nilai kalor tinggi dan zat pengotor CO2 yang rendah. Penggunaan adsorben serbuk genteng jenis ukuran yaitu fine dan coarse, yang diteliti pada selang waktu 5 dan 20 menit, untuk pengambilan data nilai kalor dan kandungan CO2. Gas Chromatography – Mass Spectrometry (GCMS) digunakan pengujian kandungan gas hasil adsorbsi. Hasil penelitian menunjukkan jenis ukuran serbuk genteng yang lebih halus (fine) memberi hasil purifikasi lebih baik dengan hasil pada menit ke 5 dan 20 masing-masing sebesar 24,1 dan 20,1 % sementara pada jenis ukuran butir coarse pada menit ke-5 dan 20 masing masing menghasilkan kadar CO2 sebesar 23,1 dan 20,8%. Karena terjadi penurunan kadar CO2 maka nilai kalor biogas setelah purifikasi tertinggi bernilai 23893 kJ/m3 setelah proses purifikasi yang telah menghasilkan penurunan kadar CO2 diketahui selama proses purifikasi berlangsung efektivitas penyerapannya terbesar adalah 59,8 % pada jenis ukuran fine pada waktu 20 menit. Semakin halus ukuran serbuk genteng maka nilai kalor semakin meningkat.

Indonesia as an archipelagic country, has ethnic, linguistic, religious, cultural and social statuses. Religious moderation is an essential aspect in managing religious life in a plural and multicultural Indonesian society. In education discourse, religious moderation is an interesting issue, where currently, people in Indonesia have given serious attention to religious moderation. The purpose of this study is to find out what aspects of the Religious Moderation Mainstreaming program for students by examining Permendikbud No. 45 of 2014 concerning school uniforms for students at primary and secondary education levels. The research method is qualitative with a literature study approach. The conclusions in this study are 1) The mainstreaming program of religious moderation in schools. Where educational institutions can play a strategic role in religious moderation. 2) School uniforms as religious moderation, 3) School uniforms and religious rights, Identity in the form of this uniform initiates people's views of the religion adopted by students, and 4) School uniforms and attitudes of nationalism in religious moderation as a culture of tolerance which is described through respecting others, nationalism is related to the student's commitment to prioritizing the national interest.

Biological heat transfer studies the transfer of heat in biological systems from inside the human body or from outside to inside the body. The biological heat transfer equation uses the Pennes equation, which applies to the layers of skin made up of the epidermis, dermis, fat, and muscle. This investigation solves the biological heat transfer equation to obtain a one-dimensional unstable temperature distribution in human skin layers subjected to cryotherapy with cold packs at temperatures of 278 K and 283 K using the finite difference method (FDM). The results show that cold compresses influence the temperature distribution on human skin due to the very significant temperature difference between the heat sink temperature and the core temperature of the human body. The greater the temperature difference, the more significantly the temperature distribution in human skin decreases. This is due to the heat transfer that occurs due to two temperature differences, namely the core temperature of the body and the temperature of the cold substance, and is also favored by differences in thermal conductivity, density, and specific heat. that exist in every layer of the skin.

The low efficiency of liquefied petroleum gas (LPG) stoves, one of which is caused by the loss of environmental heat. In order to increase efficiency, the heat loss will be captured and reflected back using a finned heat reflector. The purpose of this study was to find the effect of the material and diameter of the finned heat reflector on the efficiency and distribution of flame temperature on the LPG stove. The research was conducted on an LPG stove with a finned heat reflector installed. The conical reflector model is truncated facing upwards and made of fins that are directed at the inner side. Efficiency measurement is done by Water Boiling Test (WBT) while temperature distribution by experiment. The reflector material is varied, namely aluminum, stainless steel, and aluminum foil, while the diameter of the reflector is also varied, namely 145 mm–165 mm with a range of 5 mm. The efficiency value obtained is also compared with conventional stoves. Based on the results of the study, it was found that the finned heat reflector with 155 mm diameter stainless steel material produced the highest efficiency of 60%, an increase of 7.9% compared to conventional stoves. It was also found that the material and diameter produced the largest heat area and the highest temperature. This happens because of the complete combustion process and the optimal function of the reflector in reflecting back the radiation heat losses.

The objective in this study was to construct a finned heat radiation reflector using a cut cone-shaped stainless steel plate. In addition, its efficiency was examined by the water boiling test by varying the fin rows and angles. Measurements were performed on reflectors with one, two and three rows of fins, which were compared with conventional stoves with and finless reflectors. Furthermore, fin angles of 5°, 10°, 15°, 20° and 25° were evaluated by the variation in the fin rows, and the most efficient configuration was investigated. Results revealed that finned reflectors increase the efficiency of liquefied petroleum gas stoves. The highest efficiency (60%) was obtained for the reflector with three finned rows and a fin angle of 10°. Compared with those of conventional reflectors and reflectors without fins, 7.87% and 4.47% increase in the efficiency was observed, respectively. Furthermore, the use of finned reflectors enhanced the area of complete combustion.

The purpose of this study was to determine the effect of depth variations of the bowl blade on the performance of kinetic turbines. The test has conducted experimentally on a laboratory scale. In this study three vertical shaft, kinetic turbines were used with blade depth variations of 2 cm, 3 cm, and 4 cm. Each turbine will be tested on different rotation variations and flowrate variations. Parameters such as turbine power and efficiency will be determined based on the results of measurements of water velocity, water level, and braking load. The results showed that the depth of the bowl blade affected the performance of the kinetic turbine. The highest kinetic turbine performance was obtained in the turbine with 4 cm blade depth variation, followed by the turbine with 3 cm blade depth variation and the lowest turbine performance was obtained at 2 cm blade depth variation. The maximum performance of the turbine is obtained at 4 cm blade depth variation at 80 rpm and 65 m3/h water discharge, where the power generated is 13.2 Watts and efficiency is 34.5%.

The CO2 content in biogas is an impurity, so it needs to be reduced. One way to reduce the levels of CO2 in biogas is by purification with tile-zeolite adsorbents. The purpose of this study was to determine the use of tile - zeolite as an adsorbent in the purification process to reduce CO2 levels using a 23 factorial design. The use of tile powder adsorbents (25% and 75%) - Zeolite (75% and 25%), biogas flow rates of 1 and 6 liters/minute, which were investigated at intervals of 5 and 20 minutes, to collect CO2 content data. Gas Chromatography-Mass Spectrometry (GCMS) is used to test the adsorption gas content. The results are shown by the Pareto curve resulting from biogas purification of CO2 levels, each of which has a magnitude of response to CO2 levels. Increased levels of tile-zeolite as an adsorbent and the rate of biogas flow in the purification process had an effect of reducing CO2 levels by 44.214%. Conversely, an increase in tile-zeolite levels as an adsorbent increases CO2 levels in the biogas purification process. Natural tile is a porous material that can adsorb and has ions that can be exchanged with ions from the outside.

Biogas adalah salah satu energi alternatif yang mempunyai nilai ekonomisnya besar teruntuk masyarakat pedesaan. Dalam prakteknya kandungan CH4 biogas menjadi bagian terpenting untuk proses konversi energi namun zat pengotor berupa karbondioksida yang menurunkan nilai kalor masih besar. Sehingga diperlukan upaya untuk menurunkan CO2 dengan proses purifikasi. Tujuan penelitian ini untuk mendapatkan cara purifikasi yang meningkatkan kualitas biogas dengan nilai kalor tinggi dan zat pengotor CO2 yang rendah. Penggunaan adsorben serbuk genteng jenis ukuran yaitu fine dan coarse, yang diteliti pada selang waktu 5 dan 20 menit, untuk pengambilan data nilai kalor dan kandungan CO2. Gas Chromatography – Mass Spectrometry (GCMS) digunakan pengujian kandungan gas hasil adsorbsi. Hasil penelitian menunjukkan jenis ukuran serbuk genteng yang lebih halus (fine) memberi hasil purifikasi lebih baik dengan hasil pada menit ke 5 dan 20 masing-masing sebesar 24,1 dan 20,1 % sementara pada jenis ukuran butir coarse pada menit ke-5 dan 20 masing masing menghasilkan kadar CO2 sebesar 23,1 dan 20,8%. Karena terjadi penurunan kadar CO2 maka nilai kalor biogas setelah purifikasi tertinggi bernilai 23893 kJ/m3 setelah proses purifikasi yang telah menghasilkan penurunan kadar CO2 diketahui selama proses purifikasi berlangsung efektivitas penyerapannya terbesar adalah 59,8 % pada jenis ukuran fine pada waktu 20 menit. Semakin halus ukuran serbuk genteng maka nilai kalor semakin meningkat.

In this research, microstructures, thermal and electric properties of thin-film bismuth vanadium oxide as an anode for water electrolysis were presented. The anodes needed are obtained by centrifuging the indium thin oxides with BiVO4 powder. In order to determine the crystallinity and morphology of BiVO4, the following measurements were made: XRD, SEM, and FTIR. The thermal and electric properties were characterized by a CV meter. The results of XRD and SEM confirmed that the crystal structure of the investigated material is monoclinic and do not change from effect of spinning coating. The optimum production conditions were specify at 800 rpm and 7 s deposition time, with the average particle size is 0.3 μm. FTIR results show that for all samples, the peak received at 530 cm−1 is influenced by the vibrational bond of Bi–O. CV curves indicate increasing concentration of BiVO4 for all samples.

Conventional heat transfer system is unable to absorb heat well. Various methods have been done to enhance heat transfer. One of them is the method by using nanofluid which has been done by many researchers; due to the better thermal performances compared to base fluid. The research aims to observe the enhancement of convective heat transfer and pressure drop in the cooling process by using Al2O3 – Water nanofluid. The volume concentration of the Al2O3 varied from 0.2% and 0.3% with 30 nm diameter nanoparticles flowing in a double pipe with the opposite direction. The result showed that the increase of the particle volume concentration leads to enhance convective heat transfer coefficient and pressure drop. The two variables of measurement showed the average heat transfer coefficient increased about 21% with 0.2% and 0.3% volume concentration compared to base fluid. Pressure drop increased about 22.86% with 0.2% and 0.3% volume concentration. In conclusion, the performance of nanofluid slightly increased together with the increase of volume nanofluid concentration.

It has been known from the previous researchers that the use of the heat radiation reflector can improve the efficiency of the LPG stoves. Based on the radiation theory, the radiation energy is emitted radially in all directions. Therefore, a kind of method to guide the heat radiation is required to minimize the heat losses. One of the method is to add some fins to the reflector in order to capture the potential heat loss from the non-finned reflector. In this work, we use one fin line reflector made from a plate of stainless steel in the shape of cutted-cone. The boiling water test is used to investigate the efficiency of LPG stoves. We find that the efficiency of LPG stoves can be increased by adding one fin line reflector by about 5.21% and 1.75% than that one without reflector and non-finned reflector, respectively. The result of the temperature distribution shows that one fin line reflector enlarges the area of complete combustion.

Alternative energy sources are essentially inexhaustible for the foreseeable future, alternative energy is not only needed but to the energy transform from one form of energy to another form of energy without creating pollution that would damage the nvironment. One of these is the water potential energy, especially from rivers. In Indonesia especially the potential of river water is very much. On the river water, one of the enormous energy potential is the kinetic energy due to the flow speed and the flow rate when it can be utilized optimally then the energy crisis can be overcome. Kinetic turbine is one of the options in harnessing the kinetic energy potential in a form of flow rate. The Response Surface Methodology (RSM) is used in this research as design of experiment to obtain the optimum condition of each parameter. This study uses a kinetic turbine vertical shaft with eight arc blades. The kinetic turbine was made under a laboratory scale. The purpose of this study was to obtain an optimum condition for an arc bladed kinetic turbine performance. The Response Surface Methodology was used to obtain a turbine performance mathematical equation at an optimum condition. In this study, the independent variables used are the flow steering angle variations 30°, 40°and 50°; Flow rates of: 1.7; 2.2; 2.7 m/s; and turbine rotation of: 35, 45, 55 rpm. From the observation and analysis it is obtained a mathematical model with Y as the Turbine Power = 5.97 Watts; water flow steering angle X1 = 35,75º; a water flow rate X2 = 2.78 m/sec; and the turbine rotation X3 = 61.82 rpm. A turbine efficiency Full Quadratic models based on the response surface models analysis obtained a mathematical model too, where Y is the Turbine efficiency as big as 19.74%.

Over fuel consumption and increased exhaust gas due to the A/C system have become a serious problem. On the other hand, the LPG-fueled vehicle provides potential cooling from LPG phase changes in the vaporizer. Therefore, this article presents the potential cooling effect calculation from 1998 cm3 spark ignition (SI) engine. A numerical study is used to calculate the potential heat absorption of latent and sensible heat transfer during LPG is expanded in the vaporizer. Various LPG compositions are also simulated through the engine speed range from 1000 to 6000 rpm. The result shows that the 1998 cm3 engine capable of generating the potential cooling effect of about 1.0 kW at 1000 rpm and a maximum of up to 1.8 kW at 5600 rpm. The potential cooling effects from the LPG vaporizer contributes about 26% to the A/C system works on eco-driving condition.

Briquettes mixture of peat and charcoal leaf midrib palm oil is one of the alternative energy for replacing fossil fuel energy. It is environmentally friendly and abundant in Indonesia, mainly in South Kalimantan. In this study, the percentage of briquettes mixture of peat and charcoal leaf midrib of palm oil were 50%:50%, 60%:40%, 70%:30%, 80%:20% and 90%:10%, respectively. In addition, 1 gram of starch was added as an adhesive for every variation of briquettes mixture. In briquetting process, the pressures were 10 kg/cm2, 20 kg/cm2 and 30 kg/cm2. The combustion characteristics of briquettes was tested, then it was compared by subbituminous coal briquettes. The results show, ignition delay of briquettes decrease by increasing additional percentage of peat, however extend the burning time of briquettes, consequently the burning rate decrease and the briquettes temperature becomes low. Briquetting pressure affects the combustion characteristics of briquettes. Ignition delay of briquettes decrease by the pressure. On the other hand, extend the burning time of briquettes and decrease the burning rate, however combustion temperatures of briquettes increases. The results also show a comparison of mixture briquettes peat and charcoal palm leaf midrib with subbituminus coal briquettes. The subbituminous coal briquettes produces higher combustion temperature, the longer combustion process and the lowest combustion rate.

Some studies have been done on utilizing biomass from agriculture such as the leather and shell of rubber (Hevea brasiliensis) were not used optimally in Indonesia as an alternative energy which developed by making biobriquet to achieved the higher energy that could be used in the combustion process. In this study, the biobriquet was made of the leather and the shell of rubber by comparisson of the leather and shell were: 0%: 91%; 45.5%: 45.5%; 55%: 36%; 64%: 27%; 91%: 0%.Glyserin 9% for each percentage of biobriquet was used as adhesive material and the drying temperature of 110 C. This study aims to investigate the characteristics of biobriquet combustion which made of the leather and shell of rubber. The results shows that the biobriquet combustion process which made of 64% rubber leather and 27% rubber shell has a calorific value of 5313,923 Kal/gr. In 20 seconds of initial ignition, the combustion process shows the improvement such as increased concentrations of the flammable leather, bluish red fire.

The aim of this study is to identify the value of compounds contained in liquid coal by using Fourier Transform Infra-Red (FTIR) and Differential Scanning Calorimeter (DSC). FTIR was used to analyse the components contained in liquid coal, while the DSC is done to observe the heat reaction to the environment. Based on the Fourier Transform Infra-Red (FTIR) test results it is shown that the compound contained in the liquid Coal consisting of alkanes, alkenes and alkyne. These compounds are similar compounds. The alkanes, alkenes and alkynes compounds undergo complete combustion reaction with oxygen and would produce CO2 and water vapour [H2O (g)]. If incomplete combustion occurs, the reaction proceeds in the form of Carbon Monoxide CO gas or solid carbon andH2O. Combustion reaction that occurs in all these three compounds also produces a number of considerable energy. And if it has higher value of Carbon then the boiling point would be higher. From the Differential Scanning Calorimetric (DSC) test results obtained some of the factors that affect the reaction speed, which are the temperature, the reaction mixture composition, and pressure. Temperature has a profound influence in coal liquefaction, because if liquid coal heated with high pressure, the carbon chain would break down into smaller chains consisting of aromatic chain, hydro-aromatic, or aliphatic. This then triggers a reaction between oil formation and polymerization reactions to form solids (char).

Research and development activities on Liquefied Petroleum Gas (LPG) vehicles have increased LPG engine performance to that of gasoline engines. LPG evaporation in the fuel system also has a potential cooling effect that can be taken advantage of. The results from previous studies, however, do not explain the level of fuel in the tank at the time of data collection. LPG is a mixture of several molecules which have different properties. This paper presents an investigation of LPG composition characteristics in the fuel line during the discharging process. Samples were taken periodically on the fuel line by special gas syringes. Afterwards, the samples were injected into the Gas Chromatography-Mass Spectrometry (GC-MS) device. This series of tests, which was conducted on lengthy LPG tanks, showed that the propane and butane 2-methyl molecules are unevenly dispersed during the discharging of the tank. However, this study found that a change in LPG composition during the discharging process does not have significant influence on the energy delivery and the potential cooling effect.

Experimental studies of the Archimedes screw turbine are applied as a micro hydro power plant for low head focused on the fluid flow. Fluid flow on a screw turbine is not completely filled water flow there is still a free surface between the water fluid and atmospheric air. Except the screw geometry, the turbine screw free surface allows the flow phenomena that are important in the process of turbine screw power generation. The Archimedes screw turbine main driving force is the fluid-gravity weight, which is affected by the inflow depth, inflow velocity and the turbine shaft’s slope. The dimensionless parameter Froude number (Fr) is connected to analyze the screw turbine efficiency. The purpose of this study is to figure out the fluid flow role when power generated by a three blades Archimedes screw turbine observed visualized, and also observed the turbine rotation and torque. The observed parameters are varied in inflow depth as the characteristic length (y) of Froude Number, inflow velocity (co), and the turbine shaft slope (α). The screw turbine model, were made under a laboratory scale and made from acrylic material. The geometric form is the three bladed screws which have seven screw respectively, the number of helix turns is 21, the angle of screw blade is 30°, radius ratio of 0.54 with a pitch distance of 2,4 Ro. The result from this study revealed a phenomenon of fluid flow between the screw blades a whirlpool wave occurs or vortex due to the linear momentum in a form of the hydrostatic force against the blade screw which occurs in two opposite directions and the effect of the turbine shaft angular momentum. The vortex would affect the screw turbine power generation process as most of the kinetic energy that goes into the screw turbine sucked into the vortex between the screw blades, but this phenomenon can be reduced by reducing the turbine shaft slope. The highest turbine efficiency of 89% occurred in the turbine shaft’s slope of 25° and a flow rate of 0.5 m/s and a 1Ro characteristic length and a 0,12 Froude number.

This study attempts to reveal how the use of critical pedagogy principles in teaching English as a Foreign Language (EFL) reading facilitates students to think critically. Additionally, it investigates and elaborates the benefits and challenges of using critical pedagogy principles in teaching EFL reading. The three critical pedagogy principles used in this study were dialogic education, democratic classroom, and reading the world and the word. Critical thinking skills and dispositions expected to be performed by the participants were analysis and evaluation skills, open-mindedness, and making reasoned decision. This is a case study design which was conducted in the form of teaching program. The teaching program which consisted of eight meetings was given to 59 EFL sophomores in the Reading in Professional Context class at a private teacher education in Bandung. Data in the form of classroom talks and activities and students‟ responses as well as their critical thinking skills self-assessment were collected by using video recordings, observation notes, interview guideline, students‟ learning journals, and questionnaires. It is revealed that the teaching program has facilitated students to think critically by providing four categories of activity. They are (1) offering problematic topics and reading materials that are linked to the students‟ lives, (2) encouraging students to read between the lines, (3) distributing classroom power, and (4) creating space for students‟ voices to be heard. Meanwhile, there are two benefits of the teaching program, namely (1) language development and (2) new knowledge as well as experience acquisition. However, there are three major challenges in conducting the teaching program that are (1) the lack of classroom-friendly authentic controversial reading materials, (2) the passive culture, and (3) the unpredictable classroom.

Availability of fossil fuels in the world decrease gradually due to excessive fuel exploitation. This situations push researcher to look for alternative fuels as a source of renewable energy, one of them is kapok (ceiba pentandra) seed oil. The aim this study was to know the behavior of laminar burning velocity, secondary Bunsen flame with open tip, cellular and triple flame. Premixed combustion of kapok seed oil was studied experimentally on perforated burner with equivalence ratio (φ) varied from 0.30 until 1.07. The results showed that combustion of glycerol requires a large amount of air so that laminar burning velocity (SL) is the highest at very lean mixture (φ =0.36) in the form of individual Bunsen flame on each of the perforated plate hole. Perforated and secondary Bunsen flame both reached maximum SL similar with that of ethanol and higher than that of hexadecane. Slight increase of φ decreases drastically SL of perforated and secondary Bunsen flame. When the mixture was enriched, secondary Bunsen and perforated flame disappears, and then the flame becomes Bunsen flame with open tip and triple flame (φ = 0.62 to 1.07). Flame was getting stable until the mixture above the stoichiometry. Being isolated from ambient air, the SL of perforated flame, as well as secondary Bunsen flame, becomes equal with non-isolated flame. This shows the decreasing trend of laminar burning velocity while φ is increasing. When the mixture was enriched island (φ = 0.44 to 0.48) and petal (φ = 0.53 to 0.62) cellular flame take place. Flame becomes more unstable when the mixture was changed toward stoichiometry.

This study presents the strategy of controlling the air discharge in the prototype of small scale compressed air energy storage (SS-CAES) to produce a constant voltage according to the user set point. The purpose of this study is to simplify the control of the SS-CAES, so that it can be integrated with a grid based on a constant voltage reference. The control strategy in this study is carried out by controlling the opening of the air valve combined with a servo motor using three intelligence control systems (fuzzy logic, artificial neural network (ANN), and adaptive neuro-fuzzy inference system (ANFIS)). The testing scenario of this system will be carried out using two scenes, including changing the voltage set point and by switching the load. The results that were obtained indicate that ANN has the best results, with an average settling time of 2.05S in the first test scenario and 6.65S in the second test scenario.

Coconut oil premixed combustion behavior has been studied experimentally on perforated burner with equivalence ratio (φ) varied from very lean until very rich. The results showed that burning of glycerol needs large number of air so that the laminar burning velocity (SL) is the highest at very lean mixture and the flame is in the form of individual Bunsen flame on each of the perforated plate hole. As φ is increased the SL decreases and the secondary Bunsen flame with open tip occurs from φ =0.54 at the downstream of perforated flame. The perforated flame disappears at φ = 0.66 while the secondary Bunsen flame still exist with SL increases following that of hexadecane flame trend and then extinct when the equivalence ratio reaches one or more. Surrounding ambient air intervention makes SL decreases, shifts lower flammability limit into richer mixture, and performs triple and cellular flames. The glycerol diffusion flame radiation burned fatty acids that perform cellular islands on perforated hole. Without glycerol, laminar flame velocity becomes higher and more stable as perforated flame at higher φ. At rich mixture the Bunsen flame becomes unstable and performs petal cellular around the cone flame front.

This paper proposes a design and implementation of an axial type magnetic gear (MG) based on the composition of the magnetic arrangement. We report a quantitative comparison of two MG topologies with rectangular magnets arranged in series and parallel. Increased magnetic flux is done through magnetic circuit analysis and electrical circuit approach. Testing is done by using the rotation of a DC motor drive from 300–2600 rpm with a DC generator under load conditions. Measurement of load current and generator output power for both axial MG topologies are taken and analyzed. The results showed that the performance of an axial MG with the rectangular magnetic arrangement in parallel is better than that of a series arrangement. Based on the measured loading current of the two axial MG topologies, at generator rotation between 300–1300 rpm with 100, 200, and 300 Ω resistance loads show the same load current. Conversely, after a DC generator rotation approaches ½ of the maximum rotation (1300–2600 rpm) there is a significant increase in load current fluctuations. That is, with an increase of load currents occurring, the parallel magnetic topology shows an increase in load torque due to an increase of magnetic flux in the gear train magnets of the MG.

There are many small industryy that manufacture parts and accessories two-wheeled. Production process of parts and accessories has been done in the welding process. Welding is a common method used to connect the metal permanently. The results of observation on welding process identify there are many problems faced by operators of welding process. Welding facilities are not ergonomic and resulted in complaints of the welding operator. Results of nbm questionnaire given to operators welding showed that there are many complaints from operators. To solve the problems, this paper propose repairing on a working position and design work facilities that match with the anthropometry operators and then propose the additional aids ( jigs and a fixture ) for operators.

Continous improvements to increase productivity is compulsory for small medium enterprise. The average value of productivity observed with Objective Matrix, in January-September 2014, is 261 . The main factorwhich affect the value of productivity is the number of defective products produced by Automatic Feeding and Sealing Machine.Approximately, 73.7% of total defective products is leak product. Thus, the main effortto increase value of productivity is reduce the amount of leak products produced by those macine. After calculating the average value of productivity, design of experiment were performed using central composite design approach. Then measure optimum value for each independent variables using Response Surface Methodology. The optimal values are : Cup Type A ( supplied by PT.Indopack ) , the heater I’s temperature is 256.9 °C and the heater II’s temperature is 258.48 oC . with predicted number of leaked product is 0.86 . By using this setting , the value of productivity turned to 855, far above the average of the previous months.

Small and middle enterprises have been the important part of the economic of a nation or a local. Karang Write-Batik is one industrial center which is located at Karang Village, Semanding Subdistrict, Tuban District. Early observation shows that various processes within the production of Write-Batik are conducted without considering ergonomic aspects, such as work method and work facility. It may result in complaint and even muscle injury which is called Musculoskeletal Disorders (MSD’s) Many pronlem of pain perceived by workers are caused by less ergonomic work position or work posture. It may also be evident because the less correspondence between work equipment and workers’ anthropometry size. To measure workers’ musculoskeletal injured, the author uses Standard Nordic Questionnaire (SNQ) and to assess work posture, Quick Exposure Check (QEC) is used. The reduction of workers’ musculoskeletal injuredt can be realized by improving work facility based on workers’ anthropometry size. Result of early measurement of exposure level of several parts of body indicates that the exposure level of the back is 26, while that of the arm is 30, that of the hand wrist is 26, and that of the neck is 16. After the improvement of work facility, workers’ complaint is reduced and so is exposure level. The exposure level with the improved work facility is shown as follows: the exposure level of the back is 22, while that of the arm is 22, that of the hand wrist is 22 and that of the neck is 14.

Cedera kepala merupakan suatu pukulan atau benturan pada kulit kepala, tulang kepala, dan otak yaitumulai dari selaput otak, saraf kranial, dan jaringan otak. Kecelakaan lalu lintas yang dapat mengakibatkancedera kepala merupakan salah satu masalah kesehatan masyarakat yang dapat mempengaruhi semuasektor kehidupan. Tujuannya adalah untuk mengetahui faktor risiko yang berhubungan dengan tingkatkeparahan cedera kepala pada korban kecelakaan lalu lintas pengendara sepeda motor di RSUD Karanganyar.Penelitian ini berjenis penelitian epidemiologi observasional yang menggunakan desain penelitiancross sectional, dilaksanakan di RSUD Karanganyar, tanggal 1 Mei-31 Mei 2012. Jumlah sampel sebanyak52 responden, diambil berdasarkan kriteria inklusi dan eksklusi. Analisis data secara univariat dan bivariat(uji chi square atau uji fisher).Berdasarkan hasil analisis, faktor risiko yang berhubungan dengan tingkatkeparahan cedera kepala adalah jenis kelamin (nilai p 0,046 < 0,05), pemakiam helm Standar NasionalIndonesi (SNI) (nilai p 0,000 < 0,05), dan kecepatan kendaraan (nilai p 0,002 < 0,05). Kesimpulan penelitianini, faktor risiko yang berhubungan dengan tingkat keparahan cedera kepala adalah jenis kelamin,pemakiam helm Standar Nasional Indonesia (SNI), dan kecepatan kendaraan; Sebaiknya Dinas Kesehatanlebih meningkatkan fasilitas pelayanan kesehatan; Satlantas Polres Karanganyar, hendaknya meningkatkansosialisasi tentang peraturan undang-undang lalu lintas; Peneliti selanjutnya, hendaknya dapat menjadipembanding, dapat melengkapi kelemahan penelitian ini