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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."

"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"

"Proyeksi kebutuhan energi untuk sector transportasi di Indonesia sampai pada tahun 2025 mencapai 30% dari total energi nasional dan Sebagian besar, asal energi tersebut dari energi fosil. Untuk mengurangi ketergantungan energi fosil tersebut, maka pemerintah Indonesia membuat target penggunaan bioethanol sebagai campuran bahan bakar sebesar 20% pada tahun 2025. Selain itu penggunaan methanol juga sudah banyak diteliti dan memberikan dampak positif. Salah satunya adalah pembuatan methanol dari methana yang berasal dari proses carboncapture. Disisi lain, percampuran gasoline dengan alcohol satu macam memberikan efek COV (Coefficient of Variation) meningkat, sehingga ada kemungkinan penambahan ethanol dalam bahan bakar campuran gasoline-ethanol memberikan dampak pengurangan nilai COV, terutama pada kondisi Lean Combustion, sehingga penelitian ini ingin mengetahui efek penggunaan Gasoline Ethanol Methanol (GEM) dengan variasi campuran bahan bakar dengan udara, ditinjau dari Power, Torsi, SFC, Emisi, Serta COV. Hasilnya, nilai power dan torsi tertinggi berada di variasi λ= 1,1 pada semua GEM, selain itu, SFC terendah diperoleh pada titik E10M10 di putaran mesin 6000 RPM, dilihat dari Emisi menjadi lebih baik saat λ nilainya semakin meningkat, serta nilai COV menjadi Turun dengan penambahan methanol.

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The projected energy demand for the transportation sector in Indonesia until 2025 reaches 30% of the total national energy and most of this energy comes from fossil energy. To reduce dependence on fossil energy, the Indonesian government has made a target of using bioethanol as a fuel mixture by 20% by 2025. In addition, the use of methanol has also been widely studied and has had a positive impact. One of them is the manufacture of methanol from methane which comes from the carbon capture process. On the other hand, mixing gasoline with one type of alcohol has an increased COV (Coefficient of Variation) effect, so there is a possibility that the addition of ethanol in a gasoline-ethanol fuel mixture will reduce the COV value, especially in Lean Combustion conditions, so this study wants to know the effect of using Gasoline Ethanol Methanol (GEM) with variations in the mixture of fuel and air, in terms of Power, Torque, SFC, Emissions, and COV. As a result, the highest power and torque values are at a variation of λ = 1.1 for all GEMs, in addition, the lowest SFC is obtained at point E10M10 at 6000 RPM engine speed, seen from Emissions that get better when λ increase, and COV values decrease with the addition of methanol."