Judul: Kajian teknologi produksi benih kedelai pada berbagai agroekologi lahan di Provinsi Jambi
Abstrak: The national soybean production tend to decline in the last decade. This problem requires attention and research to find some solutions. The aim of this research is to Study the characteristic of seed grower of soybean farmers in the three agro-ecological land; Learning the technology that used by the seed grower of soybean farmers in different agro-ecological; Studying the analysis of farming technology that used and the costs incurred; and Studying the relationship between the technology and financial analysis in several agro-ecological land. This research was conducted from October 2010 through January 2011 in East Tanjung Jabung (Swamp Land), West Tanjung Jabung (Wetland irrigation) and Tebo Regency (Dryland). The method used in this research is secondary data collection on soybean seed production technology, that is the recommendation of Legume and Tuber Crops Research Institute. Furthermore, the survey method to collect primary data that obtained through interviews with seed grower directly. Purposive sampling method by seed grower as respondents, were taken of ten seed grower at each region. The results showed that age characteristics of seed grower more productive, low education levels and experience became a certified seed grower is still under four years; the implementation percentage of seed production technology in three different agroecology in the application of technology; financial analysis in three agro-ecological land is valuable as a profitable farm seed production; and there is a strong relationship between the using of seed production technology and the revenue.
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Judul: Analysis of production function and technical efficiency of soybean farms in Indonesia
Abstrak: Soybean is a main source of protein for Indonesian. Demand for soybean increased rapidly over the years, but the production grow slowly. In such situation, it is not surprising that Indonesia always imports large numbers of soybean in order to meet the national consumption. To overcome these problems, the Indonesian government has targeted to increase soybean production to achieve self-sufficiency in 2014. Increase in soybean production can be performed by increasing the number of factor production used. In soybean farming, the factors of land, seed, fertilizer, pesticides, and labor are considered as factors affecting the soybean production. Soybean production not only determined by factors production used but also by the farmers technical efficiency levels. There are three objectives in this study: (1) to identify factors that influence the production of soybean production in Java and outside Java, (2) to determine the technical efficiency of soybean farmer in Java and outside Java, and (3) to identify the factors affecting technical efficiency in the Java and outside Java. This study uses cross section data obtained from the farmer cost structure survey held by BPS in 2011. The analytical tool used to determine the factors affecting the production and measure farmers' technical efficiency is the stochastic frontier production function. The results of analysis show that soybean production in Java influenced by land, seed, KCl fertilizer, pesticides, and labor. Factors affecting production outside Java are land, seed, urea fertilizer, TSP/SP36 fertilizer, KCl fertilizer, pesticides, and labor. The average value of technical efficiency of soybean farmers in Java is 0.41. Farmer age, education level, seed aid, the use of tractors, and the use of quality seeds proved to have an influence on the technical inefficiency in Java. The average value of technical efficiency of soybean farmers outside Java is 0.6. Factors affecting the level of technical inefficiency outside Java are farmer age, education level, seed aid, fertilizer aid, counseling, and the use of quality seeds. Efforts that can be suggested to increase soybean production in Java are promoting agricultural intensification strategy. This is because the elasticity of seed, KCl fertilizer, and labor in Java is greater than outside Java. Efforts that can be suggested to increase soybean production outside Java are promoting agricultural ekstensification strategy. This is because the elasticity for land outside Java is greater than Java. Technical efficiency of farmers in Java can be improved by reducing the seed aid, introducing land preparation technology using tractors, and also increasing the use of quality seeds. Outside Java, technical efficiency improvement can be reached by reducing the seed aid, increasing fertilizer aid, optimizing counseling, and also increasing the use of quality seeds.
Keyword: soybean, production function, stochastic frontier, technical efficiency

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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