Judul: Analisis Efisiensi Produksi dan Tingkat Pendapatan Peternak Sapi Perah di Desa Cibodas, Kecamatan Cikajang, Kabupaten Garut
Abstrak: There are two dairy farmer groups in Cibodas area which are also joined theKoperasiPeternakGarut Selatan (KPGS) Cikajang. The dairy farmers are mostly smallholders, thus the dairy farms are still being maintained traditionally. Therefore, to achieve the maximum profit, the farmers should arrange the production factor allocation efficiently. Therefore, it is interesting to see as also analyzed by the writer, the farmers’ characteristics, production efficiency analysis, and the degree of income analysis. This study uses the descriptive analysis to identify the farmers’ characteristics, the double linier regression which further is being transformed into the natural logarithm form, the farmers’ degree of income analysis, and the optimum input usage analysis. The study is resulting evidences that the dairy farmers in KPGS are dominated by men, with the average age is 41-50 years old, farmers are typically finished their elementary school, with the dairy farming experiences are 11-20 on average, and the owned dairy cows are 1,8 ST. The degree of income analysis shows that with 1,8 ST owned cows per farmer, the dairy business has already profitable. The regression analysis shows that the usage of feed, concentrate, and water are significantly influenced the model with 5 percent alpha, while the worker factor is not significantly proven to influence the model. The optimum input usage analysis shows that input usage has not been optimally used in Cibodas Area, it is showed by the NPM/BKM ratio of each input is not equal with one.
Keyword: Bogor Agricultural University (IPB), optimum input, production factor, milk production, cooperative

Judul: Production efficiency analysis of dairy farm in pondok ranggon cipayung sub-district east jakarta
Abstrak: Permintaan susu sapi perah di Indonesia meningkat setiap tahunnya, namun produksinya belum memenuhi kebutuhan nasional. Peternakan sapi perah Pondok Ranggon merupakan tempat penyedia susu sapi untuk warga DKI Jakarta. Peternakan sapi perah Pondok Ranggon memiliki peranan penting dalam peningkatan produksi susu di Indonesia. Tujuan penelitian ini adalah untuk: (1) menganalisis faktor-faktor yang mempengaruhi produksi susu sapi perah, (2) menganalisis efisiensi produksi susu sapi perah, (3) menganalisis pendapatan usaha peternakan sapi perah di Pondok Ranggon. Faktor produksi susu sapi perah dianalisis menggunakan fungsi produksi Cobb-Douglas dan parameter diestimasi dengan metode Ordinary Least Squares (OLS), analisis efisiensi produksi dilakukan dengan menggunakan Nilai Produk Marginal (NPM) sama dengan harga faktor produksi, dan pendapatan usaha peternakan dilakukan dengan analisis pendapatan. Faktor-faktor yang mempengaruhi produksi susu sapi perah adalah pakan hijauan, ampas tahu, dan tenaga kerja. Nilai efisiensi masing-masing faktor produksi tidak sama dengan satu, berarti bahwa penggunanaan faktor produksi belum efisien. Nilai R/C ratio yang lebih besar dari satu, sehingga analisis pendapatan menunjukkan bahwa usaha peternakan sapi perah menguntungkan., The demand for milk of dairy cattle in Indonesia increasing every year, but the production has not fulfill the national needs. Pondok Ranggon dairy farm is a supplier milk to DKI Jakarta people. Pondok Ranggon dairy farm has an important role in improvement milk production in Indonesia. The purposes of the study were to: (1) analyze the affecting factors for the production milk of dairy cattle, (2) analyze the production efficiency of milk of dairy cattle, (3) analyze the income of Pondok Ranggon dairy farm. The production factor of milk of dairy cattle was using the production function of Cobb-Douglas analysis and estimated parameter was using Ordinary Least Squares (OLS) method, analysis production efficiency was using Value of Marginal Product (VMP) equal to production factor prices, and income of dairy farm analyze using income analysis. The affecting factors of production milk of dairy cattle is grass, tofu waste, and labors. The value of efficiency of each production factor is not equal to one, means that the use of production function have not been efficient. The value of R/C ratio is greater than one, so that the income analysis shows for dairy farm is profitable.
Keyword: analisis pendapatan, efisiensi produksi, Pondok Ranggon, susu sapi, usaha peternakan

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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