Judul: Analisis Ekonomi Pengembangan Usaha Ternak Sapi Potong di Kabupaten Garut
Abstrak: Kabupaten Garut merupakan salah satu sentra daerah pengembangan sapi potong peternakan rakyat di Provinsi Jawa Barat. Kabupaten ini memiliki populasi sapi potong yang besar dan lahan yang luas untuk ketersedian pakan hijauan. Penelitian ini bertujuan : (1) menganalisis wilayah kecamatan mana saja yang dapat dikembangkan menjadi sentra peternakan sapi potong, (2) menganalisis tingkat pendapatan dan kontribusi sektor peternakan sapi potong terhadap tingkat pendapatan petani, (3) mengevaluasi penggunaan input optimal yang akan memaksimalkan pendapatan petani dan (4) implikasi kebijakan pengembangan sapi potong di Kabupaten Garut. Metode analisis yang digunakan meliputi: Analisis Location Quotient (LQ), Analisis daya dukung lingkungan yang dihitung berdasarkan kesanggupan lingkungan memproduksi pakan hijauan untuk ternak, Analisis pendapatan dan share pendapatan usaha ternak dan Analisis efisiensi produksi secara ekonomi. Hasil penelitian menunjukkan terdapat 15 Kecamatan di Kabupaten Garut yang dapat dikembangkan untuk menjadi sentra ternak. Lima kecamatan yang potensial dikembangkan terletak di daerah Kabupaten Garut bagian selatan yaitu Kecamatan Bungbulang, Cikelet, Cisompet, Pamulihan dan Cibalong. Pendapatan peternak berada diatas Upah Minimum Kabupaten (UMK) Kabupaten Garut 2014 sebesar Rp. 1.085.000 jika minimal pemeliharaan untuk satu orang peternak sebanyak 5-6 ekor sapi potong dengan pendapatan per bulan sebesar Rp 1.687.085. Share pendapatan usaha ternak sapi potong memberikan kontribusi sebesar 49,90 persen terhadap pendapatan keluarga peternak. Optimalisasi penggunaan input produksi sapi potong agar mendapatkan keuntungan maksimum jika berat optimal sapi bakalan sebesar 185 kg, lama penggemukan selama 225 hari dengan asumsi penambahan berat sapi optimal sebesar 1,2 kg/hari maka dibutuhkan pakan bahan konsentrat secara optimal sebanyak 9 kg/ekor/hari dan input pakan hijauan sebanyak 24 kg/ekor/hari.
Keyword: usaha sapi potong, pendapatan, efisiensi produksi, optimalisasi produksi

Judul: Analisis Potensi Pengembangan Peternakan Rakyat Sapi Potong di Kabupaten Garut (Studi Kasus: Peternakan Kecamatan Malangbong)
Abstrak: Development of beef cattle breeding need to be conducted in order to fulfill the public demand of beef. The necessary informations to conduct the development of beef cattle breeding are the breeding's potential in every region and economic activities of the farmers in the region. The results of this research declare that farming activities in Kecamatan Malangbong with LQ analysis amounted 6.34 which means it is the highest breeding activities in Kabupaten Garut. The total cost of a private enclosure with a farmers amounting to IDR 30 313 639 and communal cages of IDR 29 710 747. Private cage breeders net income amounting to IDR 6 436 361 with R/C ratio of 1.21 and earning ratios of 21 percent. While the profits communal cages breeders amounted to IDR 7 039 253 with R/C ratio of 1.24 and earning ratios of 24 percent. Calculation of effective KPPTR in Kecamatan Malangbong produce a negative value of -3 150.99. Calculations obtained from the difference between the Maximum KPPTR Livestock Population Unit in Kecamatan Malangbong. Negative result means Kecamatan Malangbong is not able to accommodate the number of ruminant livestock, especially cattle. Then the development of should be implemented in other regions that have a positive KPPTR.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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