Judul: Faktor-Faktor yang Mempengaruhi Praktik Manajemen Pemeliharaan Sapi Perah pada Peternak Pemasok Susu Segar Industri Keju di Kabupaten Sukabumi.
Abstrak: This research was aimed to determine the factors that influence the maintenance management practices in farms which supply fresh milk for cheese industry. This research was conducted from June 2011 to January 2012. The respondents were ten fresh milk suppliers. The data was collected by interviewing using questionnaires. The questionnaires contained some question’s about farmer’s characteristic, the maintenance management practices, and farmer’s knowledge about subclinical mastitis and how to control it. The result showed that profile of dairy cattle farmers which most age were between 30 until 50 years old, had educated from elementary school and junior high school, and had farming experience from 1-5 years and >10 years. Half of them had attending the extention program. All of dairy cattle (100%) showed positive reaction of subclinical mastitis with IPB-1 mastitis test. The result of observation showed that respondents with good maintenance management practice were 10%, while respondents with enough and poor maintenance management practices respectively by 30%, and 60%. The significant positive correlation with maintenance management practice (p<0.05) was found between farming experience, and attending the extention program.
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Judul: Hubungan antara Produksi dan Kualitas Susu Sapi Perah dengan Faktor yang Mempengaruhi (Studi Kasus di Pondok Ranggon, Jakarta Timur)
Abstrak: Dairy cows are the large ruminants that mostly kept by Indonesian dairy farmers. The dairy farms of Indonesia located not only in the villages, but also in the urban areas, such as Pondok Ranggon in East Jakarta. Recent study was done to observe effect of technical factors on milk production and quality of dairy farms in Pondok Ranggon in East Jakarta. The parameters were environmental conditions, feeding patterns, animal conditions, lactation performance, and milk quality. The data were analyzed using multiple regression analysis. To overcome less of roughage supply, farmers used agro-industry by products such as tofu waste, soybean waste, and rice bran. The averages of roughage, concentrate, tofu waste, soybean waste and rice bran that offered to the animals were 20,85±4,27; 0,67±0,73; 28,94±7,62; 2,26±4,51; and 0,01±0,09 kg/h/d, respectively. Under this feeding regime, the average milk produced was 9,28±3,22 kg/h/d. The averages of fat, lactose, protein, solid non fat, density of milk quality were 4,44%; 4,20%; 3,91%; 8,83%; and 1,032 g/ml. The relationship of milk production(Y) on roughage (X1), concentrate (X2), tofu waste (X3), soybean waste (X4) and rice bran (X5) was Y1=2,672X10,256 X20,014 X30,018 X4-0,008 X5-0,055. The influenced of age, number of lactation, lactation days, pregnancy and body weight on milk production and quality were also confirmed. It was concluded that maximum milk production in Pondok Ranggon was produced by the cows at 2,5 years age, in the first lactation, at the second months of lactation, from heavier cows, or in the non pregnant cows.
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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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