Judul: Reducing Residual Potassium Hydroxide Levels from Coconut Cooking Oil by Adding Baffles to the Washing Equipment at Koperasi W
Abstrak: Minyak klentik kelapa merupakan minyak kelapa yang diolah secara sederhana, sehingga memiliki kandungan asam lemak bebas tinggi yang dapat merusak kualitas minyak. Terlebih jika terdapat zat yang bersifat katalis terhadap reaksi hidrolisis pada minyak seperti KOH. Efektivitas proses pencucian minyak menjadi faktor penting dalam menurunkan kadar KOH yang dapat menjadi katalisator dalam minyak. Penelitian ini bertujuan mengetahui desain alat pencucian yang dapat meningkatkan efektivitas proses pencucian minyak guna menurunkan kadar KOH dalam minyak. Untuk itu, dilakukan modifikasi alat pencucian dengan penambahan baffle untuk meningkatkan tumbukan antar komponen dalam minyak guna memindahkan komponen KOH ke dalam air. Hasil modifikasi alat pencucian menunjukkan bahwa penambahan baffle dapat menurunkan kadar KOH dalam minyak yang ditunjukkan dengan kadar asam lemak bebas melalui bilangan asam yang lebih rendah dibandingkan dengan tanpa baffle. Selain mempengaruhi kualitas produk yang menjadi lebih baik, modifikasi alat juga mempengaruhi harga pokok produksi serta harga jual produk yang meningkat dan dapat membantu koperasi untuk lebih berkembang., Coconut clectic oil is coconut oil that is processed in a simple way, so it has a high free fatty acid content that could damage the quality of the oil. Especially if there is a substance that is a catalyst for hydrolysis reaction in oil such as KOH. The effectiveness of the oil washing process is an important factor in reducing KOH levels which can be a catalyst in oil. This research aims to determine the design of the washing machine that can increase the effectiveness of the oil washing process to reduce KOH levels in the oil. For this reason, a modification of the washing machine was carried out with the addition of baffle to increase collisions between components in oil to move KOH components into water. The results of the modification of the washing machine show that the addition of baffle can lower the KOH level in the oil shown with the free fatty acid level through a lower number of acids compared to without baffle. In addition to affecting product quality for the better, tool modifications also affect the cost of production and product selling prices which increase and can help cooperative to develop more.
Keyword: baffle, coconut cooking oil, cost of production, free fatty acids

Judul: Cost Change Analysis of Coconut Cooking Oil Quality Improvement in Koperasi W
Abstrak: Koperasi W memurnikan minyak klentik menjadi minyak goreng kelapa melalui serangkaian proses pemanasan, netralisasi, pencucian, pemasakan, penyaringan, dan pengemasan. Perbaikan proses penghilangan warna dan bau telah berhasil melalui proses pemucatan menggunakan arang aktif dan bentonit. Penelitian ini dilakukan untuk menganalisis perubahan biaya dari solusi perbaikan proses pemucatan. Metode yang digunakan dalam penelitian ini adalah pengumpulan data dan analisis perubahan biaya. Analisis perubahan biaya tetap dan variabel dilakukan terhadap perbaikan proses, karena adanya penambahan bahan pemucat. Analisis kelayakan finansial dihitung atas Net Present Value (NPV), rasio pendapatan - biaya (Gross R/C), rasio keuntungan-biaya (Gross B/C), dan analisis sensitivitas. Perbaikan mutu minyak kelapa tersebut meningkatkan harga pokok produksi. Hasil analisis perubahan biaya menunjukkan nilai NPV sebesar Rp822.935.292 (positif), nilai Gross R/C 1,60 (>1), dan Gross B/C 0,60 (<1). Berdasarkan analisis NPV dan Gross R/C tersebut, perbaikan mutu minyak kelapa dinyatakan layak. Hasil analisis sensitivitas menunjukkan bahwa perubahan harga jual produk lebih sensitif daripada perubahan harga bahan baku. Dengan demikian solusi perbaikan proses pemucatan tersebut layak untuk diterapkan dan dioperasikan., Koperasi W refines crude coconut oil into coconut cooking oil through a series of processes, such as heating, neutralization, washing, cooking, filtering, and packaging. The improvement of the color and odor removal process has been successful through a bleaching process using activated carbon and bentonite. This research was conducted to analyze the cost change of the bleaching process improvement solution. The method used in this research were data collection and cost change analysis. Analysis of changes using fixed and variable costs was carried out on process improvements, due to the addition of bleaching agent. Financial feasibility analysis were calculated on Net Present Value (NPV), revenue-cost ratio (Gross R/C), cost-benefit ratio (Gross B/C), and sensitivity analysis. The improvement in the quality of coconut oil increases the cost of production. The results of the analysis of changes in costs show the NPV value of Rp822,935,292 (positive), the value of Gross R/C at 1.60 (> 1) and Gross B/C at 0.60 (<1). Based on the analysis of NPV and Gross R/C values, the improvement in the quality of coconut oil is declared feasible. The results of the sensitivity analysis show that changes in product selling prices are more sensitive than changes in raw material prices. Thus, the bleaching process improvement solution is feasible to be implemented and operated.
Keyword: coconut cooking oil, cost change analysis, process improvement

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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