Transformers play a big role in the distribution of electrical energy. One of the factors that determines the reliability level of the transformer is the life of the transformer. If the transformer is used longer, the...
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Transformers play a big role in the distribution of electrical energy. One of the factors that determines the reliability level of the transformer is the life of the transformer. If the transformer is used longer, the level reliability of its transformer will be decrease. The purpose of this research was to predict the life of a transformer based on the health index transformer calculation, then the value of health index transformer will be modeled by using artificial neural network. The results of this research were the values used as the parameters in transformer testing, which were insulating oil, furan, and dissolved gas. One of the advantages of artificial neural network methods in predicting the life of the transformer is a calculation error that can be minimized. From the result of this research, the transformer's life prediction system can be used directly to determine the lives of other transformers, both new and operating ones, with a low percentage of errors. Furthermore, this method can be used as an option in maintaining power transformers.
Biofuel has been considered as an option to substitute petroleum fuels and reduce dependence of fossil fuel importation and greenhouse gasess emissions. Current Indonesia's biofuel blending mandates are cannot ach...
Biofuel has been considered as an option to substitute petroleum fuels and reduce dependence of fossil fuel importation and greenhouse gasess emissions. Current Indonesia's biofuel blending mandates are cannot achieved due to technical, price and financial aspects. The objectives of the study are to obtain the optimum fuel supply mix by considering the fuel quality standard, production capacity and resource availability. Long-term fuel system optimization by minimum total system cost up to 2050 is carried out using TIMES-VEDA. The results showed that if goverment does not upgrade the quality of diesel up to EURO 4 and adapted EURO fuel specification with adjustment, the optimal fuel supply mix are FAME 50%-Diesel 50% in 2020-2030 and mix of FAME 47%-HVOSMR 53% in 2035-2050. For adapted EURO specification with adjustment except the sulphur content has fuel supply mix of HVOSMR 30%-Diesel 70% in 2020, FAME 20%-Diesel 80% for 2025-2030 and FAME 47%-HVOSMR 53% for 2035-2050. For gasoline, the optimum supply mix is Ethanol 5%-Gasoline 95% in 2020 and Ethanol-Ethanol2G 20%-Gasoline 80% in the 2025-2050. The utilization of biofuels can reduce the diesel and gasoline consumption for about 67-79% and 19% and reduce carbon intensity by 65-78% and 27%, respectively.
Conversion of fossil fuels as an energy source can be achieved by optimizing the use of renewable energy. One of the most used renewable energy is solar photovoltaics (PV). At present, solar power plant is an electrif...
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Conversion of fossil fuels as an energy source can be achieved by optimizing the use of renewable energy. One of the most used renewable energy is solar photovoltaics (PV). At present, solar power plant is an electrification support system for certain buildings because the abundant availability of solar radiation. On this research, Power and energy observations are carried out to determine measure the load power trend, the amount of energy flow from PV to the load, as well as import or export power from or to utility grid by direct measurement on Mosque of Faculty of engineering, Universitas Indonesia. According to the study, the highest power generated by solar power plant mostly occurs at 12:00 - 13:00 with the highest power generated by PV is 2,344 W and the exported power is 939 W, and 32.19% - 55.67% electricity energy savings consumption from utility grid.
In this study, the lateral force acting on an acoustically levitated plate in a near-field acoustic levitation setup is numerically analyzed to understand the in-plane behavior of the levitated plate. A vibrating surf...
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Indonesia had been suffered by earthquake and tsunami for many centuries. Since many lives have taken by tsunami strikes, alert and response system are very important as important part of Disaster Risk Reduction, espe...
Indonesia had been suffered by earthquake and tsunami for many centuries. Since many lives have taken by tsunami strikes, alert and response system are very important as important part of Disaster Risk Reduction, especially in area with high population density. This research conducted in Kangkung fishing village in Bandar Lampung coastal area which is an earthquake and tsunami prone area. The aim of the research is to study alert and response of Community Based Disaster Risk Reduction. The research conducted by qualitative method and purposive-descriptive approach. There were 53 respondents which participated in the survey and interview. It is reported that 'Smart Resilient City' model suitable for community needs of alert and response of earthquake and tsunami disaster. This research meets conclusion that 'Smart Resilient City' model may become a great solution in Community Based Disaster Risk Reduction to cope with the hazard of earthquake and tsunami comprehensively and sustainably.
The coatings on fruits after harvested was applied to maintain the appearance and quality up to the consumer's hands. This study aimed to maintain color and reduce the level of decay of salak madu during storage. ...
The coatings on fruits after harvested was applied to maintain the appearance and quality up to the consumer's hands. This study aimed to maintain color and reduce the level of decay of salak madu during storage. Salak madu was obtained from Madding Fresh, trader and supplier salak from Sleman, Yogyakarta. The salak was coated with Aloe vera gel (20% and 50%) and beeswax (3, 6, and 10%). All samples were stored at 25–28 °C. The parameters used to measure the effect of treatment are skin color, percentage of decay, and weight loss. Observations were carried out for 12 days. The results of this study were found that dyeing on a coating made from Aloe vera 50% was able to slow down weight loss and percentage of decay until the 6 days, while Aloe vera 30% was better at maintaining color changes during storage. Beeswax 3% coating can slow down discoloration and percentage of decay until 6 days of storage. Long-term storage (12 days) with beeswax 10% was better in maintaining changes in the quality of salak madu, while for short-term storage (6 days), beeswax 3% gives better results.
During the production, palm oil industry generated around 4 ton of dry biomass waste such empty fruit bunch (EFB), palm kernel shell (PKS), and palm oil fiber (PF) for each 1 ton of palm oil extracted. As main industr...
During the production, palm oil industry generated around 4 ton of dry biomass waste such empty fruit bunch (EFB), palm kernel shell (PKS), and palm oil fiber (PF) for each 1 ton of palm oil extracted. As main industry in Indonesia, palm oil industry offered not only the oil product but also biomass waste which was potential for clean energy sources. The utilization of those biomass residue is still limited due to lack of information related to conversion method as well as characteristic of various product. This research focuses on the product distribution and characterization of biomass pyrolysis especially PKS and PF. Pyrolysis experiments were conducted using both thermogravity (TG) method and stainless steel reactor at temperature range of 450–550°C. Based on the TG method that biomass was heated up until 1000°C in nitrogen atmosphere, PKS exhibited slower decomposition process rather than PF because of high value of hardness and fixed carbon. Two strong peaks were seen clearly which the first peak correspond to hemicellulose and lignin decomposition that proceed in the temperature range of 200 – 300°C. While, the second peak represented to cellulose and lignin decomposition that occurred in the temperature range of 300 – 500°C. Pyrolysis at higher temperature initiated smaller amount of solid product due to volatilization and higher ash content. The ash composed of several chemical such as Si, Al, Ca, Mn etc which would still remain in the solid product when temperature was increased. However, the fixed carbon and heating value enhanced significantly as increasing temperature. Clearly, based on the SEM images, the biochar hold better pore structure compared to raw material. In the pyrolysis process, the volatile matter moved to gas phases and create abundant vacant as pore structure in the solid product. These results offers opportunities of better utilization of palm oil residues not only energy conversion but also other area such as adsorbent, bio-fertilizer/
Induction motor slip ring-type technology has been widely used in industrial as one of the crucial electrical components to convert energy mechanically. The construction of this motor is more complex than other standa...
Induction motor slip ring-type technology has been widely used in industrial as one of the crucial electrical components to convert energy mechanically. The construction of this motor is more complex than other standardized induction motors such as squirrel cage. The complexity lies in the connection between the rings and brushes which requires more maintenance. Meanwhile, Squirrel cage motor that is supported by a Variable Speed Drive allows its user to start motor smoothly and adjusts the speed more efficiently. In this study, we exclusively investigate the possibility of the outdated technology replacement by using squirrel cage standardized induction motor based on its compatibility and the financial perspective as well. To prevent any coming up problems, the selections of new motor and VSD must fulfil the requirement of the existing system. Technical data were collected from customer's SCADA and nameplates. While the financial calculation was made based on the payback period. In this case, the payback period is projected within two years and the energy saving could reach 69% that basically depends on operation patterns. According to our perspective, standard squirrel cage motor potentially replaces the slip ring motor in which it is not only having a simple operation but also less maintenance and energy cost.
Gejlek or Galah is a conventional wood-made seed planting tools aid common used by corn farmers. The limited functions and heavy weight of the existing seed planting caused low productivity and long duration in planti...
Gejlek or Galah is a conventional wood-made seed planting tools aid common used by corn farmers. The limited functions and heavy weight of the existing seed planting caused low productivity and long duration in planting activity. The aim of the research is to design and to develop seed planting tools which able to accommodate user needs. User-Centered Design (UCD) methods used to design product focused on customer satisfaction. 15 respondents involved in this research to measure productivity, practicality, reliability and ergonomic. Validity test represent by F-value produce result test in between 0.354 to 0.625 where Ftest > Ftab means reject H0 or seed planting tools design able to fulfil user needs and different from previous design. User test show how work load against pulse measurement improve 26.44% and Nordic Body Map decrease by average 25% which mean there are significant improvement in terms of work load and ergonomics. It helps increase work productivity.
This paper presents the design and analysis of welding fixtures based on transient thermal analysis. Welding fixtures is designed to hold and support the workpiece securely during the welding process. The heat transfo...
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