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"This study aimed to analyze the heat release rate from the combustion process of bioethanol from sago waste to determine the viability and feasibility of low-concentration bioethanol as an alternative fuel. The heat release rate, exhaust gas, and flame temperature were measured using a cone calorimeter, and bioethanol combustion was conducted using the pilot ignition method, with an ethanol quality range of 60–70%. The analysis that the heat release rate of 60% bioethanol combustion ranged from 20 to 140 kW/m2, while a lesser range resulted from 70% bioethanol combustion (18–45 kW/m2). The flame temperature for 60% bioethanol was found to be 440°C, while the smoke and orifice temperature was 150°C. The combustion of 70% bioethanol produced a flame temperature of 450°C and a smoke and orifice temperature of 120°C after approximately 6 min of combustion. This study contributes a solution for meeting the energy demand in rural areas, where the access to and availability of major fuel resources are limited. In addition, from the obtained results, this research concluded that bioethanol made from sago waste is suitable as a clean and alternative fuel for household applications in rural areas."

"[Bioethics developed as an academic and clinical discipline during the later part of the 20th century due to a variety of factors. Crucial to this development was the increased secularization of American culture as well as the dissolution of medicine as a quasi-guild with its own professional ethics. In the context of this moral vacuum, bioethics came into existence. Its raison d’être was opposition to the alleged paternalism of the medical community and traditional moral frameworks, yet at the same time it set itself up as a source of moral authority with respect to biomedical decision making. Bioethics serves as biopolitics in so far as it attempts to make determinations about how individuals ought to make medical decisions and then attempts to codify that in law. Progressivism and secularism are ultimately the ideology of bioethics.;Bioethics developed as an academic and clinical discipline during the later part of the 20th century due to a variety of factors. Crucial to this development was the increased secularization of American culture as well as the dissolution of medicine as a quasi-guild with its own professional ethics. In the context of this moral vacuum, bioethics came into existence. Its raison d’être was opposition to the alleged paternalism of the medical community and traditional moral frameworks, yet at the same time it set itself up as a source of moral authority with respect to biomedical decision making. Bioethics serves as biopolitics in so far as it attempts to make determinations about how individuals ought to make medical decisions and then attempts to codify that in law. Progressivism and secularism are ultimately the ideology of bioethics., Bioethics developed as an academic and clinical discipline during the later part of the 20th century due to a variety of factors. Crucial to this development was the increased secularization of American culture as well as the dissolution of medicine as a quasi-guild with its own professional ethics. In the context of this moral vacuum, bioethics came into existence. Its raison d’être was opposition to the alleged paternalism of the medical community and traditional moral frameworks, yet at the same time it set itself up as a source of moral authority with respect to biomedical decision making. Bioethics serves as biopolitics in so far as it attempts to make determinations about how individuals ought to make medical decisions and then attempts to codify that in law. Progressivism and secularism are ultimately the ideology of bioethics.]"

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Pertumbuhan kendaraan bermotor selama lima tahun terakhir mencapai 8.63% per tahun. Peningkatan jumlah kendaraan berdampak pada meningkatnya konsumsi bahan bakar. Kondisi ini menunjukkan bahwa Indonesia masih tergantung pada sumber energi tak terbarukan. Energi biomassa seperti bioetanol merupakan salah satu energi alternatif yang sedang dikembangkan. Penambahan bioetanol dan bensin tentunya akan mengubah properties bahan bakar, bahan bakar akan lebih sulit terbakar dengan sendirinya sehingga tekanan yang dihasilkan dalam ruang bakar akan lebih konsisten. Studi ini dilakukan untuk menganalisis pengaruh sebaran data tekanan terhadap rata – rata nya (COV) pada penambahan 5% (E5), 10% (E10) dan 15% (E15) bioetanol terhadap kinerja mesin seperti BHP, Torsi, SFC dan IMEP dan heat release. Hasil studi menunjukkan bahwa nilai COV terkecil diperoleh sebesar 1.49% yang dihasilkan pada campuran E15 pada putaran 8500 rpm. Penurunan COV memberikan dampak pada proses pembakaran yang lebih konsisten sehingga proses pembakaran lebih baik, hal ini ditunjukkan dengan turunnya nilai SFC, meningkatnya heat release, penurunan emisi gas CO dan HC serta peningkatan emisi gas CO2 dan O2.

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The growth of motor vehicles over the past five years has reached 8.63% per year. Increasing number of vehicles has an impact on increasing fuel consumption. This condition shows that Indonesia is still dependent on non-renewable energy sources. Biomass energy such as bioethanol is one of the alternative energies being developed. The addition of bioethanol and gasoline will certainly change the fuel properties, the fuel will be more difficult to self-ignite so the pressure generated in the combustion chamber will be more consistent. This study was conducted to analyze the effect of the distribution of pressure data on its average (COV) at the addition of 5% (E5), 10% (E10) and 15% (E15) bioethanol to engine performance such as BHP, Torque, SFC and IMEP and heat release. The results of the study show that the smallest COV value is obtained at 1.49% which is produced in the E15 mixture at 8500 rpm. Decreasing COV has a more consistent impact on the combustion process so that the combustion process is better, this is indicated by a decrease in SFC values, increased heat releases, reduced CO and HC gas emissions and increased CO2 and O2 gas emissions.

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"A cement plant that produces 8,300 tons per day releases 265,000 Nm3/h of flue gas at 360°C from its Suspension Preheater (SP) and 400,000 Nm3/h of hot air at 310°C from its air quenching cooler (AQC). It is imperative to recover the waste heat emitted by the plant for power generation, i.e., Waste Heat Recovery Power Generation (WHRPG). This paper aims to optimize waste heat recovery from the cement plant using Response Surface Methodology (RSM), for which an Organic Rankine Cycle (ORC) is applied for electric power generation. The working fluid of an ORC power generation system was selected among candidates of organic working fluids (i.e., isobutane, isopentane, benzene, and toluene) by using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), a Multi-Criteria Decision Analysis (MCDA) method. The ORC power generation system configuration and the corresponding operating conditions employing the selected working fluid (i.e., pressures and temperatures) are optimized by applying RSM. Based on TOPSIS evaluation and considering factors of health, safety, environment impacts, cost, and power generated, isopentane was selected as the working fluid for the ORC WHRPG, which was configured to consist of a boiler, two expansion turbines, a reheater, and a recuperator. Implementation of RSM attained optimum operating conditions of high pressure turbine, low pressure turbine, and condenser at 11.3 bar-a saturated vapor, 4.3 bar-a and 184°C, and 1.8 bar-a, respectively. Finally, the gross electric power generated of 5.7 MW at 12.5 percent of energy conversion efficiency is generated by the pertinent ORC WHRPG."