Judul: Analisis Risiko Produksi Ikan Black Ghost di Unit Pendederan I Arifin Fish Farm Kota Bogor, Jawa Barat
Abstrak: Apteronotus albifrons known as the black ghost fish are fish that originated from South America. One of the fish farmers who produce fish black ghost in the city of Bogor is Mr. Arifin. Each production cycle fluctuations fish survival rate, this indicated the existence of risk. The purpose of this study is (1). identify risks faced by Mr. Arifin production in units of fish nursery I blackghost (2). analyzing the probability and impact of risk sources encountered Mr. Arifin in unit nursery I fish black ghost. (3). determine appropriate strategies to address the risks faced by Mr. Arifin production in the nursery unit I fish black ghost. Data obtained from field observation and interviews with business owners. Then the data were analyzed with descriptive methods and risk analysis. Results obtained by analysis of sources of risk in Arifin fish farm is changes in water quality, and fish disease attacking each other. Value of the probability and impact of each risk is 43,3% change in water quality and Rp 1,060,436, the disease was 48,0% and Rp 1,848,419, fish attacked each other at 34,5% and Rp 248,781. Sources of risk management strategies fish use to attack each other preventive strategies. Sources of risk management strategies and changes in water quality by using preventive and mitigation strategies.
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Judul: Risiko Produksi Pendederan Ikan Hias Black Ghost pada Anggota Kelompok Tani Batara Mina Sejahtera di Kecamatan Bogor Utara
Abstrak: Ornamental fish is one of the potential fishery commodities which has some advantages than other fish. Black Ghost is one of the export ornamental fish commodities and has a potential business opportunity. One of the farmer groups in Bogor city is Batara Mina Sejahtera (BMS). The problem faced by BMS is different fish survival rate from the Black Ghost fish mortality. This research objectives are to identify production risk sources, to analyze the production status of risk, and to determine handling alternative to reduce the Black Ghost nursery production risk. This research use several method such as descriptive analyze, z-score, and Value at Risk. Sources of production risk in Black Ghost nursery of BMS members at North Bogor is different survival rate between farmer because mortality from water quality, seed quality, diseases, and human resources. The highest status risk production is water quality and the lowest risk sourcers is human resources. The handling alternative which can reduce of risk production are preventive and mitigation.
Keyword: production risks, ornamental fish, Black Ghost

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology