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ABSTRACT:In this study, a thermoelectric generation (TEG) unit was designed and constructed to evaluate the technical potential of exhaust heat recovery system for automobile applications. The TEG system was made up of a commercial thermoelectric module of TEC1 12706 model, an aluminum duct, an aluminum fin heat sink, an electric heater, a cooling fan, AC and DC power supply, an external resistive load and data collection devices. The heater was used as an exhaust heat source simulator to supply heat energy to the hot side of the TEG module. The cooling fan was used for simulating airflow and maintaining uniform heat rejection from the heat sink to the ambient. The experimental investigation had been conducted to characterize the TEG's performance. The tests were undertaken based on the measurements of temperature at both hot and cold sides of the TEG module, open circuit voltage, and output voltage and current under various external resistive loads. The test results showed that the highest temperature difference was 40.1 o C. This revealed a peak output power of 178.2 mW, a load voltage of 1156.3 mV, a load current of 220 mA and a conversion efficiency of 0.204%. The thermoelectric generation from waste heat energy of a simulated automobile exhaust is technically feasible, though the output power and the conversion efficiency of the TEG unit seem low. In general, it is found that the temperature difference between the hot and cold sides of the thermoelectric module has the most significant impact on the TEG's performance.

Cooling machines have a direct contribution to environmental damage including depletion of ozone layer and global warming caused by the leakage and discharge of synthetic refrigerants (HCFC and HFC) into environment. The discharge of refrigerant into the environment is 60 percent of service sector. Some obstacles found when making a model of a refrigerant waste treatment system since it could only be used for CFC (R-12)/R-134a refrigerants. This research aims at redesigning a machine made beforehand thus it can process various refrigerant wastes used in hospitality industries which involved several components such as compressors, oil separators, filters and distillers for recycling R410A refrigerants. By having this ability, all refrigerant waste can be recycled. Result shows that the redesigned machine can recycle refrigerant waste and the signal can be reused. Calculation results on COP cooling system using pure R 410A showed 4.5, whereas by using recycled R 410A refrigerant 4.3 was obtained. COP using recycled refrigerants was lower than the one using pure refrigerants due to contamination of dirt, oil and other elements. However, with COP value of 4.3 the system performance is still good, therefore the recycled R410A refrigerant can be reused.

This progress report contains about the achievement of the implementation of the program of research in the development of teaching materials in the form of an integrated jobsheet. The second stage of the development will be done in 2018 with the goal to find: 1) the evaluation result from the expert, lectures, and students, 2) the obstacles during the try out, and 3) the feasibility of the jobsheet draft as a lab teaching material. Research using Dick & Carey development model, in review and test the research involving 2 experts, 7 course lectureres,and 24 students in mechanical engineering department. Data obtained using questionnaire enclosed and open questionnaire. Data were collected in the form of comments and suggestions as well as the evaluation result toward the integrated jobsheet were analyzed by descriptive qualitative and quantitative improvement. The test results stated: 1) the content expert test is very decent; design / media expert is very decent; individual very decent; small group is very decent; and field testing of students and lecturer decent and very decent. 2) components that need to be revised from the entire contents of the test results and instructional design experts to field test were: The contents of the summary should be more material-oriented than the summary of jobsheet parts, in addition to trouble shooting ignition problems, it is necessary to add maintenance material that is preventive maintenance, assessment rubrics for evaluation /practical tasks need to be made in more detail from simple to complex practices. Summary and evaluation analysis tools must be clear, the amount of test practice material so that there is a balance of theory and practice, the size of the book should be chosen for an elegant appearance, especially if proposed to ISBN. Based on test data and analysis of the abovementioned, teaching material draft can be declared eligible as the practical of teaching jobsheet. This research only reached the stage of formative evaluation on Jobsheet, it is expected in the future to do more research to determine its effectiveness in an effort to increase the competence of students.

The Balinese people cannot be separated from their cultural and religious customs. The religious procession for Balinese people is conducted to express our gratitude to Ida S ang Hyang Widi Wasa (The Almighty God) for the gift he has given. One of the ceremonial facilities used is tumpeng, and in aseries of ceremony, a lot of tumpeng is usually needed. As the result, many people turn this opportunity into a business. One of the villages in Gianyar regency, namely the Buruan village, Blahbatuh subdistrict, the community has a lot to do with the ir tumpeng penet business. In this village, the craftsmen still encounter many obstacles in the drying process of the cone. Nowadays, the drying process is still using the manual method by drying it under the direct sunlight. The disadvantage of this process is that this process takes long enough time and can only be done in the season. For this reason, some efforts are required to make in order to help the craftsmen of tumpeng increase their productivity, in which the distribution of air in the drying process of tumpeng will be tested in this research by using a multilevel rack type drying machine. The purpose of this research is to get the design of an air circulation system which is evenly distributed in the drying chamber of the tumpeng drying machine with multilevel rack type. The method used in this study is to make a multilevel rack type drying machine with 6 levels with an LPG gas source as a test tool. By using the existing test equipment several types of air distribution will be tried to be created to get an even air distribution system in the drying chamber. Each thermocouple will be installed on a rack to find out the temperature that occurs on each rack. From the results of the research, it turns out that the rack temperature in the lowest rack position (near the heat source) produces the highest temperature, and the rack above it has a lower temperature with an average of ∆T 35 o C this data is obtained on the system without the circulation of hot air in the drying chamber. After the process of air distribution in the drying chamber, even though the lowest rack has the highest temperature, yet the differrence of temperature between the shelves is not too large; the average between shelves reaches 10 ° C.