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: Marketing Analysis of Milk in Cijeruk Area Bogor Regency and Pondok Rangon East Jakarta
Abstrak: Pengembangan subsektor peternakan khususnya ternak perah sangat potensial, salah satu ternak perah yang potensial untuk dikembangkan adalah sapi perah. Pengembangan suatu usaha dipengaruhi salah satunya oleh efisiensi tata niaga produknya. Penelitian ini bertujuan untuk menganalisis sistem tata niaga susu sapi di Cijeruk dan Pondok Rangon yang meliputi saluran tata niaga, fungsi tata niaga, dan struktur pasar . Penentuan sampel peternak dilakukan dengan teknik purposive sampling dengan melibatkan jumlah masing masing 20 peternak sapi perah yang berada di kawasan Cijeruk dan Pondok Rangon. Lembaga-lembaga tata niaga yang terlibat dan berperan dalam saluran pemasaran susu sapi segar yaitu konsumen, loper dan kelompok pengumpulan susu ditentukan berdasarkan informasi dari peternak sampel. Berdasarkan hasil penelitian terdapat 4 saluran tata niaga di Kelompok Ternak Mandiri Sejahtera, dan terdapat 3 saluran tata niaga di Kelompok Tani Swadaya Pondok Rangon. Peternak yang ada di Kelompok Ternak Mandiri Sejahtera dominan memasarkan susu melalui kelompok, sedangkan peternak yang ada di Kelompok Tani Ternak Swadaya Pondok Rangon dominan memasarkan susu melalui loper. Saluran tata niaga paling efesien adalah saluran yang memiliki biaya pemasaran sebesar Rp.0 dengan hasil farmer,’s share 100% yaitu peternak menjual susu segar langsung ke konsumen (jalur tata niaga terpendek)., The development of the livestock sub-sector, especially dairy cattle, is very potential, one of the dairy cattle that has the potential to be developed is dairy cattle. The development of a business is influenced by the efficiency of its product trading system. This study aims to analyze the trading system of cow's milk in Cijeruk and Pondok Rangon which includes the trading system, the function of the trade system, and the market structure. The determination of the farmer sample was carried out by purposive sampling technique involving the number of each of 20 dairy farmers in the Cijeruk and Pondok Rangon areas. The trading institutions that are involved and play a role in the marketing channel of fresh cow's milk, namely consumers, deliverymen and milk collection groups are determined based on information from sample farmers. Based on the results of the study, there are 4 channels of trade in the Independent Prosperous Livestock Group, and there are 3 channels of trade in the Independent Farmer Group of Pondok Rangon. Farmers in the Independent Sejahtera Livestock Group dominantly market milk through groups, while farmers in the Pondok Rangon Self-Help Cattle Farmers Group market milk through deliverymen. The most efficient trading channel is a channel that has a marketing cost of Rp. 0 with a farmer's share of 100%, that is, farmers sell fresh milk directly to consumers (shortest trade route).
Keyword: peternak rakyat, sapi perah, susu segar, tata niaga, commerce, dairy cows, fresh milk, smallholder farmers

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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