Judul: Analisis Produksi dan Pemasaran Kakao di Kabupaten Padang Pariaman Propinsi Sumatera Barat
Abstrak: The aim of this research is to analyze factors that influence cocoa production, identified marketing chanel of cocoa, estimated marketing margin and determined farmer share. This research used survey method to cocoa farmer and wholeseller. Production analysis using Cobb-Douglas fuction and to analyze marketing structure, conduct and performent analysis is used. The result of this research show that cocoa production influenced by labour, manure, chemical fertilizer, land area, number of plants produced dan farmer education. Performance marketing of cocoa in Kabupaten Padang Pariaman is inefficient. It is based on margin indicators and farmer share. According to result number of fertilizer and plants produced need to optimalize in order to increased cocoa production. Bargaining power of cocoa farmers need to increased by optimalize farmer association.
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Judul: Analysis and development direction of smallholder cocoa plantation in Padang Pariaman Regency, West Sumatra Province
Abstrak: Cocoa demand as industrial raw materials continues to increase, both in domestic and overseas markets. This causes the cocoa price is quite high and relatively stable. Due to the role and its potential, a cocoa as one of promising plantation commodities which can be developed to support regional development in Padang Pariaman Regency. Padang Pariaman Regency is the second largest producer of cocoa in West Sumatra with a total area of 13,312 ha plantation in 2011 with a production of 15,540 tons. Seen from productivity, Padang Pariaman Regency has the highest cocoa productivity compare with other cities in West Sumatra, which is 1.17 tons/ha. Considering the potential development of cocoa in Padang Pariaman Regency, research and analysis needs to be done so that people do not plant cocoa in locations that do not comply with the criteria for crops growth (biophysical), spatial and economic aspects. It required guidance for people in choosing the right location in order to obtain maximum yields. In addition, feasibility factor, market aspect and factors that influence development of cocoa plantations according to stakeholders are also need to be considered. The objectives of this reseach are: (1) to analyze potential location for development of cocoa plantations based on biophysical aspects, environment and availability of land, (2) to analyze financial feasibility of cocoa plantation on each of the land suitability classes, (3) to analyze the chain, margin trading system and market integration of cocoa commodity in Padang Pariaman regency, (4) to analyze factors that influence development of cocoa plantations in Padang Pariaman regency according to stakeholders, (5) to arrange development direction of smallholder cocoa plantation in Padang Pariaman Regency. The experiment was conducted for 6 (six) months, from April to September 2013 in the Padang Pariaman Regency. Research activities consist of: preparation, field data collection, processing and analysis of data and writing of the thesis. This study uses primary and secondary data. Primary data were obtained through direct observation in the field by using questionnaires and interviews. Secondary data and maps obtained from the relevant agencies. The analysis methods used in this study are analysis of Geographic Information Systems (GIS), financial analysis, margin analysis, marketing chains and market integration, and Analytical Hierarchy Process (AHP). The results show that potential area for development of smallholder cocoa plantations based on biophysical aspects and land availability area in Padang Pariaman Regency is 51,342 ha, while not potential/suitable land is 2,754 ha. Locations of potential area presented in the map form. The results of financial analysis show that cocoa plantations in the Padang Pariaman Regency feasible to be developed, seen from values of Net Present Value (NPV), Net Benefit Cost Ratio (Net BCR), and Internal Rate of Return (IRR). NPV value is positive of Rp 45,094,495 in S2 land suitability class and Rp 35,985,486 in S3 land suitability class. Meanwhile, BCR values obtained are 7.23 and 5.07, respectively. IRR exceeds the existing interest rate (12%), which illustrates that the interest rate up to 40.45% for S2 class and 33.39% for S3 class smallholder cocoa plantation in Padang Pariaman Regency still provide benefits to
Keyword: cocoa, development direction, financial feasibility, land suitability

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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