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Vocational graduates' readiness for selecting careers is an important topic for vocational education research. Although there have been many studies on vocational student career selection readiness, there are only few studies on the roles of teaching quality, social capital, and psychological capital in shaping vocational students' readiness for selecting careers. This study aims to examine the antecedent factors of high school students' readiness for career selection which involve teaching quality, psychological capital, and social capital factors. This study employed the quantitative approach with ex-post facto design. The data were randomly collected from 279 vocational high school students in North Lampung-Indonesia by means of online questionnaires. SEM analysis was carried out in this study to see the effects among variables. The results show that readiness for selecting careers is influenced by teaching quality and psychological capital, as social capital does not directly influence student readiness. Besides, psychological capital is influenced by teaching quality and social capital. Then, social capital is influenced by teaching quality. Social and psychological capitals together mediate the effect of teaching quality on the readiness for selecting careers. The research findings present some implications for vocational education practitioners wishing to make further improvements.

Utilization of durian shell waste as feed biomass in the pyrolysis process has been carried out. The results of the pyrolysis process produce bio-oil, gas, and biochar. Pyrolysis biochar can be used as a potential source of energy by converting it into biochar briquettes. This research is making biochar briquettes using a mixture of water and starch. The ratio between biochar and starch is 9: 1. The mixed material is then made biochar briquettes using a briquette printer with a pressure of 0.5 MPa. The results showed that biochar briquettes had better performance than durian shell biomass.

Wind turbines are devices that convert wind kinetic power into electrical energy through generators. Currently there has been a lot of research on horizontal shaft type wind turbines to improve systems that work optimally. This study uses a 3 blade horizontal winglet wing turbine wind turbine with variations in pitch angle to increase the cut in speed value. The pitch angles used are 0°, 2°, 4°, 6°, 8°, and 10°. This study uses an NACA 4412 aerofoil with winglets added to the blade tip. The research method used in this study is the experimental method. The results showed that the highest cut-in speed values of three, four and five blades were obtained at a pitch angle of 10° at wind speeds of 2.3 m/s, 1.8 m/s and 1.8 m/s.

The characteristics of B20 biodiesel droplet combustion on flame propagation rate at microgravity conditions are fascinating to study. The observation of Biodiesel B20 fuel was chosen because it supports the Indonesian government policy on the use of alternative energy. This research is an initial stage to determine the effect of variations in the speed of motion of biodiesel B20 droplets on the flame propagation distance. At this initial stage, the droplet velocity is set at 5 mm / s. There are three droplets used, namely droplet A (igniter droplet), droplet B (flame source droplet), and droplet C (observation droplet). Each droplet has a diameter of 1 mm. Data was collected directly through video analysis to determine the propagation distance of SBC/d0. The results showed that the investigative droplet (C), which was 3 mm from droplet B, had a maximum burnt distance of SBC/d0 = 4 - 4.2.

This research was aimed to analyze the effect of adding pitch angle to the performance of a Savonius Hybrid Type S-Darrieus Type H-Rotor wind turbine with variations in wind speed. This research used an experimental method with variations in pitch angle and wind speed. Variables taken in this study are wind speed, pitch angle addition, and wind turbine cutting speed. Variations in the addition of pitch angles are 0°, 5°, 10°, 15 °, 20°, 25°, 30°. The results showed that the addition of pitch angles to the blade influenced the cut in speed. The highest cut in speed is 4.2 m/s at the addition of pitch 0° while the lowest cut in speed is at 3.8 m/s at the addition of a 30° pitch angle.

The coastline of Demak city shows an increase in the need for electrical energy every year, in line with an increase in pond production. Currently, electricity needs are supplied from diesel generators. However, the use of diesel generators as electricity generators causes pond production costs to increase. On the other hand, the coastal location of Demak has wind potential, which can be used as a power plant. In this study, a numerical study was carried out using the savonius wind turbine as a power plant in the coastal area of Demak city. This research’s initial stage was to collect data on wind characteristics during the day and night conditions. Wind speed data are then used as input parameters in the numerical simulation using the ANSYS R.15 software. This study compares simulations between Savonius wind turbines without using fins and using fins for placement on the coast of Demak. The simulation results show that the wind speed on the coast of Demak ranges from 2 to 3.5 m / s. In these wind conditions, the savonius wind turbine with one fin has a power coefficient (Cp) better than without the fin. The relationship between wind speed and the electric power produced has been simulated and discussed in depth in this paper.

Energy demand in the form of portable devices to supply electronic equipment increases every year. Micropower Generator is an alternative solution for portable energy generation. The most crucial component in micropower generation is micro-combustion. The problem faced in micro-combustion is the presence of a stable flame in the combustor. This study aims to produce flame stability on the combustor by using several fuels such as acetylene gas and propane gas. The micro combustor used in this study is a cylinder type with an inlet diameter of 3.5 mm, an outlet diameter of 4.5 mm, and a wall thickness of 0.5 mm. The micro-combustor is made of stainless steel with a burned region of 10 mm and an unburned region of 40 mm. The results showed that the combustor wall’s temperature with propane fuel reached the highest average temperature at 182.45°C, while 113.20 °C for acetylene fuel.

The effect of global warming has raised public awareness to seek energy sources that do not damage the environment and can be renewed, such as renewable energy. Renewable energy that is practically applied in people’s homes, namely sun and wind. This research studies about solar panels to determine the highest electrical power produced. Measurements are made by measuring the voltage and electric current generated by solar panels and measuring wind speed to determine the electrical power generated by wind turbines. This research was conducted in the Campus area of Universitas Sebelas Maret Surakarta. Solar panels produce the highest electric power of 26.42 Watts. This study states that solar panels produce electric power that is more effective and optimal than wind turbines. The power produced by the solar panels is 26.42 Watt, while the wind turbine produces electric power of 6.46 Watt.

The binary power plant is a geothermal power generation system used at low to medium temperature levels and used indirect system. In this system, the heat generated from the reservoir is channelled to the secondary working fluid which has a lower boiling point than water using a heat exchanger. In this case, the Organic Rankine Cycle (ORC) is a suitable system for use. This improves the performance and efficiency of the plants. However, in this system, the installation configuration of the ORC model is an important factor that can affect its performance. The selection of an improper ORC design reduces the thermal efficiency of the system. Therefore, it cannot utilize heat optimally. In this study, Engineering Equation Solution (EES) simulation program is used to run the system as in operation conditions. A comparative analysis is conducted using ORC, Regenerative ORC (RORC), and RORC with Internal Heat Exchanger (IHE). The results indicate that RORC with IHE has the greatest value for both energy (21.74%) and exergy efficiency (25.26%) while net power produced 5479 kW. This shows the addition of OFOH and IHE can increase these factors, improve performance and reduce energy degradation from the cycle.

T his research a imed to: (1) determine the daily water needs of Belang population, (2) designing hydram pump installation based on water needs and geographical conditions of Belang village, (3) study the performance and efficiency of the hydram pump, (4) study the role of the hydram pump to fulfill the daily water needs of Belang population. This study was based on Research and Development (R & D). It developed hydram pump installation to fit the topography of Belang village so it can work optimally. The pump was tested by varying waste valve length at 20 mm, 25 mm, 30 mm and 35 mm; and waste valve ballast at 0 grams, 250 grams, 500 grams and 750 grams. Data collection was performed three times for each variation. Hidram pump performance was determined by the efficiency and the volumetric discharge of water produced during the pump operation. Hydram pump was designed based on standard of the daily water needs which reach s 13650 liters/ day for 195 Belang’s people . In this study, h ydram pump has some parameters . They are 4,5 meters of supply height , 80 meters of delivery height, 4 inches of pump body diameter and 1 inch of delivery pipe. Based on the tests that have been conducted , the highest efficiency of the hydram pump shown at 30 mm of waste valve length and 250 grams of waste valve ballast ( η = 0.486652 , q = 6.746969 L / min) . T he maximum volumetric discharge was presented at 35 mm of waste valve length and 750 grams of waste valve ballast (q = 7.522211 L / min , η = 0.380989). Hydram pump performance c ould fulfill the water need eed in Belang Village until medium term maintenance level . They could use the water for drinking, cooking, bathing, washing, until cleaning home by 9750 liters/ day. Keywords: hydram pump, pump designing, pump performance, pump ef f i c iency, Tlogolele Selo Boyolali

Organic Rankine Cycle is a technology that convert low-temperature heat sources into a mechanical energy, and it can be used to produce electrical energy in a closed system. The heat sources can be received from renewable energy such as geothermal, solar, and biomass. Furthermore, the ORC system can also be used to increase energy efficiency in the industry by utilizing the waste heat produced. Therefore, there are two classification of the ORC system, namely a heat recovery system and binary power plant. Recently, the ORC system has made a thrive in the geothermal power plant. The ORC system can be applied to resources with low to medium temperature characteristics (

Currently, optimizations of biomass pyrolysis processes become an exciting topic. This is due to the increasing requirement of energy. This study focuses on the optimization pyrolysis process of solid waste of palm starch that became an environmental problem. The objectives of this study are to optimize the pyrolysis process of palm starch waste, especially liquid smoke product. The optimization of the liquid smoke product had conducted through the modification of connecting-tube between pyrolysis reactor and condenser. The connecting tube has differences in diameter, length, and material. The results of the study show variations in size and type of tube affect the product yield of the pyrolysis process. Stainless-steel pipes have better performance to produce liquid-smoke. The shorter the length of the pipe increases the quantity of liquid-smoke, but the smaller the diameter of the pipe decreases the quantity of liquid-smoke. This paper discusses in more detail the comparison of the performance of connecting tube by modifying the type of material, the length, and the diameter of the pipe.

The research aims to investigate the condition of Basuki boiler based on the ratio between fuel consumption and steam production. The research used quantitative-descriptive method. The population of this research was daily record of Basuki boiler. The sample was daily record of Basuki boiler performance for 1 year (February 2015 to January 2016). The sample was taken using purposive sampling method. The research analyzed the ability of fuel to produce a ton (1000 kilograms) of steam. The ability of fuel was depended on the highest heating value (HHV) and water contain in the coal. Based on the result of the research, it can be concluded that Basuki boiler condition based on its ratio between fuel consumption and steam production was good, because the ratio that shown (144.09) was less than the company’s target (150), it meant that the boiler only used 144.09 kilograms of coal to produce a ton of steam. The average of fuel consumption for 1 year was 1,484.99 kg/h and the average of steam production was 10,305.76 kg/h.