The job satisfaction is reflected by the affective reaction of an individual on to his/her work related factors. This study explores the relationship between individual characteristics, job characteristics, and career development with job satisfaction of teachers in vocational schools at the Province of North Sumatera, Indonesia. The sample size of this study was obtained using the proportional random sampling which further resulting a total number of 166 teachers who were found having the expected qualification in Mechanical Engineering subject. The hypotheses tests based on the path analysis on the research model revealed that individual characteristics, job characteristics, and career development directly influence job satisfaction. Summary of findings and managerial implications in this study are discussed and put forward.

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Biomass has been known as a source of energy with a thermochemical process that produces heat and can be converted further into electricity. However, thermal energy losses are a huge problem during combustion. To overcome this problem, a system based on organic Rankine cycle (ORCs) was developed to recover and utilize them to generate electricity. The proposed ORCs include an evaporator, a turbine, a condenser, and a pump coupled with a biomass carbonizing system to create a promising technology for small-scale electricity generation. In this work, a thermodynamic modelling equation based on energy and exergy balances was briefly expressed for each subcomponent of the system. A case study with R134a as the working fluid is being investigated to validate the system’s performance. In addition to the effects of R134a on temperature at the turbine exit, the suitable operating pressures has been specially adopted from several valid journals that focused on the effects of a wide range of possible operating pressure on the working fluid characteristics, which have a significant effect on the system performance. Finally, the theoretical analysis shows that the turbine work is profitable at an inlet pressure of 5 bar and an outlet pressure of 2 bar. This system is recommended to be integrated into the thermochemical biomass process. Recommendations have been made for the future development of small-scale biomass-fuelled power generation systems. This study shows that the thermal losses of the biomass thermochemical processes can be theoretically recovered in the form of electricity by using ORC efficiently.

This research aimed to enhance the performance of biomass combustion-based stove. Thermal performances were assessed in terms of power output (Pout), specific fuel consumption (SFC), thermal efficiency (ηth), and burning rate (BR). These performances were expected to meet the minimum standards established by the Indonesian biomass stove alliance regarding the use of a healthy and energy-saving of biomass stove in Indonesia. The stove tested was an improved stove with an advantage on the air distributor by adding a component to administrate air combustion needed placed on the centre of the combustion zones. This is a very effective way to distribute air for combustion required where the air could reach all the fuel and the combustion product that occupy entire the combustion zones to ensure high combustion zone temperature. Coconut shell was used as feedstock. This biomass was found abundant in Indonesia and was widely used as heat source by burning it directly. The coconut shell was sized uniformly about 5 cm x 5 cm, dried by utilizing sun energy. To estimate the stove performances, several combustion tests was carried out where the air flow rate into the stove (Qa) and the amount of biomass fuel (mb) referred as the air–fuel ratio (A/F) were considered. The Water Boiling Test (WBT) was performed to assess this improved stove. Parameter required such as initial mass of coconut shell, the mass of residual ash, the initial mass of water, mass of water after boiling, and the time required to boil as well as combustion flame temperature were recorded and used to determine the performance of the improved stove studied.

The main problem related to thermal energy is that the thermal energy must be used directly and immediately as generated. For example, the thermal energy of solid waste combustion can be directly utilized for power generation. However, studied of thermal energy storage technology is still placed on the second opinion on waste to heat energy. The heat can be stored using a simple or mobilized system which can store thermal energy and can be brought to somewhere it is needed, for example on domestic heating or drying usage. This article studied and evaluated a micro thermal energy storage system from household waste combustion into a warm water that is great for washing clothes, dishes, shower, and other purposes of household needs. System considered was a simple manner and water is used as the heat energy storage medium. In this study, the equations for initial parameter calculation were presented theoretically based on thermodynamic principle. This paper is hopefully beneficial to the researchers and engineers for preliminary design and development of a heat storage systems technology.

Tujuan penelitian ini adalah untuk mengetahui kualitas pembimbing skripsi mahasiswa oleh dosen pembimbing di lingkungan Fakultas Teknik Universitas Negeri Medan. Penelitian ini merupakan penelitian survey eksploratif terhadap kinerja dosen pembimbing skripsi, sebagai bahan masukan untuk pengembangan pedoman penulisan skrpsi dan upaya peningkatan kualitan pembimbingan skripsi. Subjek penelitian adalah mahasiswa yang sedang dalam pembimbingan skripsi dan alumi. Alat pengumpul data menggunakan angket penilaian kinerja dosen dalam pembimbingan skripsi. Jumlah sampel yang telibat sebanyak 269 responden. Teknik analisis data digunakan analisis deskriptif. Hasil penelitian menunjukkan bahwa (1) Ketersediaan buka pedoman penulisan skripsi sangat membantu kelancaran pelaksanaan pembimbingan baik bagi dosen maupun mahasiswa, (2) Pola pembimbingan secara umum telah dilaksanakan secara rutin dan terjadwal melalui kegiatan tatap muka, korespondensi, dan melaui email, (3) Hasil analisis data dari tiga aspek penilaian diketahui bahwa aspek kedisiplinan sebesar 74% dalam kategori cukup disiplin, aspek kompetensi profesionalisme dosen sebesar 77% dalam kategori cukup kompeten, dan aspek kompetensi sosial dan kepribadian sebesar 66% dalam kategori cukup kompeten. Rekomendasi yang disampaikan adalah perlunya komitmen jadwal pelaksanaan pembimbingan sehingga masing-masing memiliki tanggung jawab untuk melakukan kegiatan pembimbingan secara terjadwal.

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Government policies in Indonesia have been pushing in the past decade towards 100% electrification target by end of 2020. However, many of the new energy policies are reused from previous policies designed for different objectives causing overlap in policies between the central and local governments. Local distributed generation are not fully controlled by local stakeholders and community, and with the lack of long-term planning, continuous government incentives and support, they are bound to fail due to the lack of maintenance. The use of solid biomass for household has decreased significantly due to the government support for LPG stoves that overtaken other government projects supporting biomass. Small-scale biomass research is showing good progress towards the implementation of novel methods for biomass utilization. However, majority of the medium and large-scale projects are still relying on old technologies such as direct biomass combustion in boilers rather than the more environment friendly gasification technology. Another major biomass contribution to national energy mix is through liquid biofuels. This work summarizes the current and prospective energy mix in Indonesia and the main conventional and non-conventional energy sources and their environmental concerns. This work also gathers the latest local biomass research and biomass power plant projects.