Judul: Analisis Risiko Produksi Ikan Cupang (Betta splendens) di KPC Lebak Oca Mandiri Semplak Bogor
Abstrak: Ikan hias merupakan salah satu komoditi perikanan yang membantu menggerakan perekonomian nasional melalui perolehan devisa. KPC Lebak Oca Mandiri merupakan kelompok pembudidaya cupang yang terbentuk pada tahun 2014. Usaha pembenihan ikan cupang memiliki prospek yang tinggi karena menawarkan peluang memperoleh profit yang cukup besar, namun kemungkinan untuk mengalami risiko usaha sewaktu-waktu dapat terjadi. Penelitian ini bertujuan mengidentifikasi sumber-sumber risiko produksi dan menganalisis probabilitas serta dampak risiko yang disebabkan oleh sumber-sumber risiko produksi pada usaha pembenihan ikan cupang di KPC Lebak Oca Mandiri. Data diperoleh dari observasi dan wawancara dengan pemilik usaha, kemudian dianalisis menggunakan metode Z-score dan Value at Risk (VaR). Hasil penelitian diperoleh sumber risiko yang terdapat pada KPC Lebak Oca Mandiri meliputi perubahan suhu, kualitas induk, dan penyakit. Nilai probabilitas dan dampak pada masing-masing risiko, di antaranya perubahan suhu 32,3% dan Rp2.002.110,00; kualitas induk 22,1% dan Rp141.330,00; penyakit 57,5% dan Rp2.233.000,00., Ornamental is one of the fishery commodities that help move national economy through foreign exchange earnings. KPC Lebak Oca Mandiri is a group of betta cultivators that was formed in 2014. Betta fish hatchery business has high prospects because it offers the opportunity to earn a large enough profit, but the possibility of experiencing business risks can occur at any time. This study aims to identify sources of production risk and analyze the probability and impact of risks caused by sources of production risk in betta fish hatchery business at KPC Lebak Oca Mandiri. The data were obtained from observations and interviews with business owner, then analyzed using the Z-score and Value at Risk (VaR) methods. The results obtained that the sources of risk contained in KPC Lebak Oca Mandiri include changes in water temperature and water quality, broodstock quality, and disease. The probability and impact values for each risk are changes in water temperature and water quality 32,3% and Rp2.002.110,00; broodstock quality 22,1% and Rp141.330,00; disease 57,5% and Rp2.233.000,00.
Keyword: Betta Fish Hatchery, Cultivation, Probability, Production Risk

Judul: Supply Chain Analysis of Betta sp. At Betta Aquaculture Group (KPC) Lebak Oca Mandiri Semplak Bogor
Abstrak: Rata-rata produksi ikan cupang di KPC Lebak Oca Mandiri akibat adanya pandemi mencapai 1000 ekor ikan cupang perbulan pada tahun 2019 sampai saat ini, sedangkan sebelumnya pada tahun 2018 hanya 500 ekor ikan cupang perbulan yang diproduksi. Pemenuhan permintaan terhadap ikan cupang tidak lepas dari sistem rantai pasok. Penelitian ini bertujuan menganalisis proses, jejaring, pelaku, efisiensi dan peluang risiko yang terdapat pada rantai pasok ikan cupang. Data diperoleh dengan metode studi kasus. Analisis data menggunakan margin pemasaran, farmer’s share, dan metode failure mode and effect analysis (FMEA). Hasil penelitian menunjukkan bahwa proses produksi ikan cupang terdiri dari pemijahan induk, pemeliharaan larva, pembesaran, dan pemasaran. Aliran informasi yang mengalir pada rantai pasok yaitu mengalir secara dua arah, aliran barang yang mengalir dari hulu ke hilir, dan aliran harga yang mengalir dari hulu ke hilir. Pelaku rantai pasok ikan cupang di KPC Lebak Oca Mandiri terdiri dari pembudidaya, pedagang kecil 1, pedagang kecil 2, pedagang besar 1, pedagang besar 2, eksportir, dan konsumen akhir. Rantai pasok ikan cupang yang terjadi dari pembudidaya menuju ke pedagang kecil 1 merupakan rantai pasok yang paling efisien. Penyakit pada kegiatan budidaya ikan cupang merupakan peluang risiko yang memberikan dampak tertinggi., The average production of betta fish at KPC Lebak Oca Mandiri due to the pandemic has reached 1,000 betta fish per month in 2019 until now, whereas previously in 2018 only 500 betta fish were produced per month. Meeting the demand for betta fish cannot be separated from the supply chain system. This study aims to analyze the processes, networks, actors, efficiency and risks contained in the betta fish supply chain. Data obtained by case study method. Data analysis uses marketing margins, farmer's share, and the failure mode and effect analysis (FMEA) method. The results showed that the betta fish production process consisted of brood spawning, larval rearing, rearing, and marketing. The flow of information that flows in the supply chain is flowing in two directions, the flow of goods that flows from upstream to downstream, and the flow of prices that flows from upstream to downstream. Betta fish supply chain actors at KPC Lebak Oca Mandiri consist of cultivators, small traders 1, small traders 2, wholesalers 1, wholesalers 2, traders and end consumers. The supply chain for betta fish that occurs from cultivators to small traders 1 is the most efficient supply chain. Disease in betta fish cultivation is a risk opportunity that has the highest impact at KPC Lebak Oca Mandiri.
Keyword: aquaculture, betta fish, marketing margin, supply chain

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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