Judul: Rancangan Produksi Pati Umbi Talas (Colocasia esculenta L.)
Abstrak: Talas adalah umbi lokal yang mudah dibudidayakan dengan potensi produksi hingga 40 ton per hektar. Pati talas dapat berpeluang sebagai pati substitusi untuk memenuhi permintaan pati dalam negeri karena kandungan pati umbi talas yang tinggi. Tujuan dari penelitian ini adalah mendapatkan rancangan proses produksi pati talas serta mendapatkan tingkat kelayakan proyek produksi pati talas. Penelitian diawali dengan mengumpulkan data dan memilih metode yang tepat dengan mempertimbangkan beberapa parameter. Kemudian dilakukan perancangan proses dan perhitungan neraca massa. Berikutnya adalah analisis produksi secara rinci meliputi penentuan mesin dan peralatan, perhitungan energi, penjadwalan sederhana, dan perancangan tata letak. Serta diakhiri dengan analisis kelayakan rancangan produksi secara finansial. Produksi pati talas dirancang dengan bahan baku 30,000 ton umbi talas setiap tahunnya dengan hasil pati sebanyak 6,258 ton. Proses produksi meliputi pengupasan, pencucian, perendaman, pembilasan, penghancuran, pemerasan, penyaringan, pengeringan, serta pengemasan. Kebutuhan biaya investasi sebesar Rp2,461,387,500 dan biaya produksi Rp158,703,449,352 per tahun. Industri pati talas layak secara finansial dan memiliki nilai NPV Rp85,662,370,592; IRR 23.93%; B/C ratio 1.53; dan Payback Period 5.17 tahun., Taro is a local tuber that is easy to cultivate with potential production up to 40 tonnes per hectare. Taro starch has an opportunity as a substitute starch to meet domestic demand for starch due to the high starch content of taro tubers. The purpose of this research is to get the design of the taro starch production process and to get the feasibility level of the taro starch production project. The research begins with collecting data and selecting the appropriate method by considering several parameters. Then do the process design and mass balance calculations. Next is a detailed production analysis covering the determination of machines and equipment, energy calculations, simple scheduling, and layout design. And ended with a financial feasibility analysis of the production design. The production of taro starch is designed with a raw material of 30,000 tons of taro tubers each year with a starch yield of 6,258 tons. The production process includes stripping, washing, soaking, rinsing, crushing, squeezing, filtering, drying, and packaging. The investment cost required is IDR 2,461,387,500 and the production cost is IDR 158,703,449,352 per year. The taro starch industry is financially viable and has an NPV value of IDR 85,662,370,592; IRR 23.93%; B/C ratio 1.53; and Payback Period 5.17 years.
Keyword: financial analysis, production design, taro starch

Judul: Desain Proses Produksi Maltodekstrin Menggunakan Pati Talas Dengan Enzim α-amilase.
Abstrak: Pati talas sangat potensial dijadikan sebagai pati industri karena memiliki swelling power dan peak viscosity yang tinggi, serta membentuk struktur gel yang halus. Penelitian ini bertujuan untuk mendesain proses produksi maltodekstrin dari pati talas menggunakan enzim α-amilase. Tahapan dalam penelitian ini terdiri dari pemilihan alternatif proses, penentuan alur proses, perhitungan neraca massa, pemilihan mesin dan peralatan, penentuan tata letak pabrik, dan analisis finansial. Produksi maltodekstrin diawali dengan mereaksikan 600 kg pati talas yang disuspensikan dalam larutan CaCl2 dan enzim α-amilase sebagai katalisator dalam reaktor berpengaduk. Hasil pencampuran tersebut akan dimurnikan melalui proses ultrafiltrasi dan nanofiltrasi, kemudian dikeringkan dalam spray dryer. Produk yang diperoleh adalah 314,56 kg maltodekstrin dengan kadar air 3%. Kebutuhan energi listrik adalah 321,5 kWh/batch-nya. Tata letak bangunan ditentukan dengan metode Activity Relationship Chart (ARC) dan Total Closeness Rating (TCR). Luas bangunan produksi sebesar 211 m2, dengan luas tanah 300 m2. Desain proses produksi maltodekstrin dari pati talas layak secara ekonomi, dengan NPV sebesar Rp 7 016 913 045, Net B/C sebesar 4,61, IRR sebesar 47,43%, dan PP 3,12 tahun., Taro starch has potential to be used an industrial starch because it has high swelling power dan peak viscosity, and form a smooth gel structure. This study aims to design a production process of maltodextrin from taro starch. The stage of this study consist of selecting alternative processes, determining process flow, calculating mass balance, selecting machinery and equipments, determining plant layout, and economic analysis. Maltodextrin production begins by reacting 600 kg of taro starch in CaCl2 solution and α-amylase enzyme using a stirred tank reactor. The reaction result will purified by ultrafiltration dan nanofiltration methods, then dried by spray dryer. The yield of this process is 314,56 kg of maltodextrin with 3% of moisture content. The electrical energy required by production machinery dan equipments is 321,5 kWh/batch. Production building layout is determined by Activity Relationship Chart (ARC) dan Total Closeness Rating (TCR).. Production building area is 194 m2, with land area is 300 m2. Maltodextrin process design is economically feasible, with Rp 7 016 913 045 of NPV, 4,61 of Net B/C, 47,43% of IRR, and 3,12 years of payback period.
Keyword: Design process, feasibility, maltodextrin, taro starch

Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
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