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"Implan biodegradable memiliki nilai lebih karena tidak memiliki efek jangka panjang pasca pemasangan dan tidak memerlukan operasi pengangkatan implan. Kandidat yang cocok untuk implan jenis ini adalah Magnesium (Mg). Dalam aplikasi implan biomedis diperlukan permukaan bahan yang bersifat bioaktif di dalam tubuh, oleh sebab itu biasanya implan berbasis Mg dilapisi permukaannya dengan mineral tulang hidroksiapatit (HA). Dalam penelitian ini, HA tidak digunakan sebagai bahan pelapis melainkan digabungkan dengan Mg dalam bentuk komposit. Metode yang digunakan untuk fabrikasi komposit Mg-HA adalah metalurgi serbuk dan pemadatan dengan Spark Plasma Sintering (SPS). SPS dipilih karena metode ini memiliki kemampuan densifikasi yang tinggi. Penelitian ini dilakukan untuk mengidentifikasi pengaruh waktu milling yaitu 3, 4 dan 5 jam terhadap ukuran partikel dan menganalisa pengaruh komposisi HA yaitu 0, 10, 20, 30 wt% pada sifat korosi dan bioaktivitas komposit yang dihasilkan. Hasil optimasi dengan nilai densitas komposit menunjukkan waktu milling optimum adalah 4 jam dan variasi komposisi HA pada Mg-30HA. Sampel Mg, Mg-10HA, Mg-20HA, dan Mg-30HA dengan waktu milling 4 jam memiliki densitas berturut-turut 1,766; 1,872; 1,832 dan 1.877 g/cm3. Uji XRD menunjukkan kehadiran kedua fasa yaitu Mg dan HA secara terpisah.

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Biodegradable implants are beneficial because they do not have long term effects after installation and do not require post-surgery to remove the implant. Magnesium (Mg) is a suitable candidate for this type of implant. In biomedical implants application, a bioactive surface is required. Therefore, Mg-based implants are usually coated with the bone mineral hydroxyapatite (HA). In this study, HA is not used as coating but mixed with Mg to form composite. The fabrication method used powder metallurgy and compaction method of Spark Plasma Sintering (SPS). SPS was chosen because this method has a high densification capability. This research was conducted to identify the effect of milling time (3, 4, and 5 hours) which resulted in variations in particle size and to analyze the effect of HA composition that is 0, 10, 20, 30 wt% on the resulting composite characteristics. Optimization results with composite density values indicate the optimum milling time is 4 hours and the variation of HA composition in Mg-30HA. Mg sample; Mg-10HA; Mg-20HA and Mg-30HA with a 4-hour milling time have a density of 1.766, respectively; 1,872; 1,832 and 1,877 g/cm3. The results of the XRD showed the presence of the two phases Mg and HA separately."

"PLTBm merupakan salah satu alternatif untuk menyediakan kelistrikan di daerah 3T (Terdepan, Terluar, dan Tertinggal). Dalam hal ini feedstock yang digunakan adalah sekam padi. Sejalan dengan pengembangan syngas sekam padi sebagai bahan bakar alternatif, maka dalam penelitian ini difokuskan untuk mengevaluasi unjuk kerja dan mendapatkan pemanfaatan syngas yang ideal dan optimal untuk mesin spark ignition. Syngas berasal dari proses gasifikasi downdraft gasifier dengan bahan bakar sekam padi. Dilakukan pengujian dengan memberikan putaran konstan 1500 rpm pada generator listrik dengan mengevaluasi perbandingan antara penggunaan bahan bakar bensin beroktan 98 dan bahan bakar syngas. Pembebanan dimulai dari 1 kW sampai dengan 4 kW dengan interval 1 kW. Metode pemasukan syngas dengan T junction yang diletakan sebelum intake manifold untuk mencampur udara dan syngas. Pengukuran dilakukan terhadap laju massa alir udara, laju massa alir bensin, dan laju massa alir syngas. Temperatur kerja mesin, dan mengukur tegangan serta arus yang dihasilkan. Hasil penelitian menunjukan bahwa unjuk kerja mesin spark ignition mengalami perubahan efisiensi termal serta SFC yang lumayan besar antara bahan bakar bensin dengan bahan bakar syngas. Sedangkan,, untuk daya efektif, torsi dan juga BMEP tidak mengalami perubahan yang signifikan. Serta juga menghasilkan AFR untuk bahan bakar bensin cukup kaya bahan bakar sedangkan untuk bahan bakar syngas sudah mendekati 1:1 dengan udara luar.

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PLTBm is an alternative to provide electricity Front, Outermost, and Disadvantaged areas. In this case, the feedstock used was rice husk. In line with the development of rice husk syngas as an alternative fuel, this research is focused on evaluating the performance and obtaining the ideal and optimal use of syngas for spark ignition engines. Syngas comes from the downdraft gasifier gasification process with rice husk as fuel. Tested by providing a constant rotation of 1500 rpm on an electric generator by evaluating the comparison between the use of 98 octane gasoline and syngas fuel. Loading starts from 1 kW up to 4 kW with 1 kW intervals. Syngas intake method with a T junction placed before the intake manifold to mix air and syngas. Measurements were made on the mass flow rate of air, the mass flow rate of gasoline, and the mass flow rate of syngas, and then measure engine temperature, the voltage and the current generated. The results showed that the performance of the spark ignition engine change in thermal efficiency and a fairly large SFC between gasoline fuel and syngas fuel. However, the effective power, torque and also BMEP did not experience significant changes. Morever, produces AFR for gasoline fuel is quite rich in fuel while for syngas fuel it is close to 1:1 with outside air."

"Pada abad ke-21 ini, tantangan utama yang dihadapi dunia adalah bagaimana mengelola konsumsi energi secara berkelanjutan tanpa mengorbankan keberlanjutan lingkungan dan sumber daya alam. Kebutuhan energi Indonesia dari tahun ke tahun mengalami peningkatan seiring dengan meningkatnya pertumbuhan ekonomi dan jumlah penduduk Indonesia. Bahan bakar minyak telah menjadi tulang punggung utama dalam pemenuhan kebutuhan energi global selama puluhan tahun. Berdasarkan Energi Outlook Indonesia yang dikeluarkan oleh BPPT pada tahun 2022, Konsumsi BBM di sektor transportasi pangsanya mencapai 73,5% pada tahun 2012 dan terus meningkat menjadi 90,3% pada tahun 2021. Oleh karena itu, inisiatif pengembangan bahan bakar alternatif harus mulai dilakukan yang nantinya dapat digunakan oleh masyarakat. Pemerintah melalui Peraturan Presiden Nomor 22 Tahun 2017 tentang Rencana Umum Energi Nasional menyatakan bahwa bioetanol yang diproyeksikan sebagai substitusi dari bensin (gasoline) ditargetkan pada tahun 2025 hingga seterusnya ditargetkan sebesar 20%. Akan tetapi penambahan kandungan etanol dalam bahan bakar memiliki kekurangan dimana sifat dari bahan bakar tersebut akan menjadi lebih korosif dari sebelumnya. Sifat korosif ini dapat menyebabkan kerusakan pada bagian mesin yang mengalami kontak langsung dengan bahan bakar tersebut. Maka dari itu perlu adanya penambahan zat aditif sebagai inhibitor sifat korosi dari bahan bakar campuran etanol. Penelitian ini dilakukan dengan menggunakan mesin Honda Supra 125 FI dan dihubungkan dengan dynamometer serta alat gas analyzer untuk menganalisis hasil tenaga dan emisi yang dihasilkan oleh mesin. Sebagai variasi untuk mendapatkan data yang lebih banyak dan melihat pengaruh dari campuran aditif dalam bahan bakar, penelitian ini akan menggunakan variasi konsentrasi aditif dan dua tipe aditif yaitu

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Tert-Butylamine dan Lemongrass Oil. In the 21st century, the main challenge faced by the world is how to manage energy consumption sustainability without compromising environmental sustainability and natural resources. Indonesia's energy demand increases year by year in line with the country's economic growth and population increase. Oil fuel has been the backbone of fulfilling global energy needs for decades. According to the 2022 Indonesia Energy Outlook issued by BPPT, fuel consumption in the transportation sector reached a share of 73.5% in 2012 and continued to increase to 90.3% in 2021. Therefore, initiatives to develop alternative fuels must be started, which can later be used by the public. The government, through Presidential Regulation No. 22 of 2017 concerning the General Plan for National Energy, states that bioethanol, projected as a substitute for gasoline, is targeted to reach 20% by 2025 onwards. However, the addition of ethanol content in fuel has a disadvantage in that the fuel becomes more corrosive than before. This corrosive property can cause damage to parts of the engine that come into direct contact with the fuel. Therefore, it is necessary to add additives as inhibitors of the corrosive properties of ethanol-blended fuels. This research was conducted using a Honda Supra 125 FI engine connected to a dynamometer and a gas analyzer to analyze the power and emissions produced by the engine. To obtain more data and observe the influence of additive mixtures in the fuel, this research will use variations in additive concentrations and two types of additives, namely Tert-Butylamine and Lemongrass Oil."

"The success of his titles Digital Fortress, Deception Point, Angels and Demons, The Da Vinci Code, and The Lost Symbol has made Dan Brown a household name - but how did he achieve this? This book includes a look at his early years as a musician, teacher, and humorist, and it examines the crucial role that his wife, Blythe Brown, plays in his life and work. It examines his skillful storytelling and extraordinary attention to detail, and reveals how important research is to his books, and how through careful study, he brings to light ancient rites and rituals that are buried deep within the collective subconscious. This combination of Brown's imagination with the secret truths, myths, and legends from a variety of ancient institutions - including the Freemasons and the Catholic Church - are perhaps why his novels are so successful, and, at times, controversial. This insightful look into the world of Dan Brown will enthrall, entertain, and unlock the secrets of one of the world's most exciting and enigmatic writers."

"Machine learning focuses on predition-- using what you know to predict what you would like to know based on historical relationships between the two. At its core, it's a mathematical/algorithm-based technology that, until recently, required a deep understanding of math and statistical concepts, and fluency in R and other specialized languages. "Machine learning with Spark and Python" simplifies machine learning for a broader audience and wider application by focusing on two algorithm families that effectively predict outcomes, and by showing you how to apply them using the popular and accessible Python programming language. This edition shows how pyspark extends these two algorithms to extremely large data sets requiring multiple distributed processors. The same basic concepts apply. Author Michael Bowles draws from years of machine learning expertise to walk you through the design, construction, and implementation of your own machine learning solutions. The algorithms are explained in simple terms with no complex math, and sample code is provided to help you get started right away. You'll delve deep into the mechanisms behind the constructs, and learn how to select and apply the algorithm that will best solve the problem at hand, whether simple or complex. Detailed examples illustrate the machinery with specific, hackable code, and descriptive coverage of penalized linear regression and ensemble methods helps you understand the fundamental processes at work in machine learning. The methods are effective and well tested, and the results speak for themselves"