Judul: Analisis Keunggulan Komparatif dan Kompetitif Usahatani Padi Semiorganik di Desa Ciburuy, Kecamatan Cigombong,Kabupaten Bogor
Abstrak: If the views of potential resources and condition of agricultural markets organic products is increasing, then Indonesia has a great opportunity to be producers of organic food. It was realized by the government to make the program “Go Organic 2010”, where one of the purpose is to encourage the development of organic farming who have the competitiveness and sustainability. This research wanted to see rice farming semiorganic run by farmers in the village Ciburuy have comparative and competitive advantages or not. The results of this research are: 1). Semiorganic rice farming run by each farmer characteristics have comparative and competitive advantages, as indicated by PCR and DRC values smaller than one. The land sharecroppers farmers value is 0.851 and 0.826. The land tenant farmers value is 0.532 and 0.632. The farmers owner land value is 0.608 and 0.616; 2). Based on the sensitivity analysis, the most sensitive indicator of the decline occurred in the conditions of the selling price of output, and decrease the amount of output. For indicators the increase of anorganic fertilizer price is not overly sensitive, due to the use of anorganic fertilizers is not too much in rice farming semiorganic.
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Judul: Comparative Analysis of Techincal Efficiency of Semi Organic and Conventional Rice Farming in Bogor [Case in Situ Gede and Sindang Barang Villages].
Abstrak: Rice is a sub sector of agriculture and economic that very important and strategics. The needed for food is increasing from year to year. This is because increasing of population. An increasing number of needs caused the government to implement the green revolution program to increase rice productivity. However, the application of green revolution give impact to environmental pollution due to the use of chemical fertilizers and pesticides. Impact of pollution caused by use of chemicals for agriculture cause people aware with environment and health. West Java is one of Indonesia's rice-producing areas. However, rice cultivation in West Java still use chemical fertilizers and pesticides and several new areas to develop organic farming. Areas that have started organic farming one of them in the city of Bogor, which is in Situ Gede Village, Sindang Barang Village, and Mulyaharja Village.Because there are still many problems to become the organic rice so that only Situ Gede village that is still developing semi organic rice until now. Nevertheless, Bogor city government is developing organic rice farming program again. However, because there are some provisions that must be fulfilled to be organic rice so few producers called the organic rice with semi organic or healthy rice. Production and income of semi organic rice farmers organic not fully in line with expectations. Semi organic rice production is still low (about 5-6 tonnes/ha) so that farmers incomes were low. Besides that, sometimes semi organic rice prices are still the same as conventional rice prices because of marketing uncertain. Indicated that a narrow planting area causing less efficient farmers in cultivation. Organic rice cultivation by semi-organic rice farmers indicated was not efficient due to the high cost of producing organic rice, farmers' income levels are still low, rice production is still below potential output and the price of organic rice that is not much different even with rice conventional. To reach organic rice farming takes time, long proces and sustainable process. This study aims: (1) to analyze the factors that influence semi organic and conventional rice farming, (2) to analyze technical efficiency semi organic and conventional rice farming and (3) to analyze rice farming income between semi organic and conventional rice farming. To answer these research purposes the data were analyzed qualitatively and quantitatively with stochastic frontier Cobb Douglas production function. The estimation results of stochastic frontier production function semi organic rice farming, the production function models considered fit for fulfilling the assumption of Cobb-Douglas. Estimation results of the production function with the MLE method shows that there are three variables with a positive and significant coefficient on rice production is semi organic land area, elements of K and organic pesticides. Land use positively and significantly with the elasticity of 0.994 indicates that the addition of 1% land area will increase rice production amounted to 0.994% with other factors held constant. The elasticity of the element K to the production of 0.005 showed that the addition of elements of K by 1% would increase rice yield by 0.005% with other factors held constant. Botanical pesticides variable positive and significant
Keyword: stochastic frontier, organic farming, production, inefficiency

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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