Judul: Analysis and Development Strategy of Pineapple Horticultural Agriculture Based on Rural Youth Empowerment
Abstrak: Pineapple (Ananas comosus (L.) Merr.) Is one of Indonesia's leading agricultural commodities. West Java ranks the third largest pineapple producer in Indonesia, where 92% or approximately 130,956 tonnes of its production comes from Subang Regency. Pineapple production in Subang Regency in 2019 reached 187,448.2 tons. The largest pineapple centers in Subang Regency are concentrated in Jalancagak, Ciater and Cijambe Districts where the total production reaches 98% of the total pineapple production in Subang Regency. Besides having great potential, it turns out that pineapple corm farming still faces many problems. Among the issues that are considered very important are related to the decline in production and productivity of pineapple corms. In 2017 pineapple production in Subang Regency reached 238,647.9 tons but in 2018 the production decreased to only 187,448.2 tons or decreased by 23%. This study aims to formulate a pineapple fruit horticultural development strategy based on empowering village youth. The research location is in Cirangkong Village, Subang Regency. This research was conducted in October 2019-September 2020. The subjects of this study consisted of respondents and informants. Data collection for program evaluation determined 30 pineapple farmer respondents participating in the Dompet Dhuafa program. Collecting data for a survey of rural youth perceptions of agriculture took a sample of 50 village youths. The informants used in this study consisted of pineapple farmer / farmer figures, community leaders, village youth leaders, village officials and assistants of Dompet Dhuafa. The data used in this study are primary data and secondary data. Primary data were collected through surveys, observations, in-depth interviews and group discussions. Meanwhile, secondary data were collected from documents relevant to this research. Techniques in the formulation of strategies and action programs in this study use the Logical Framework Approach (LFA) method, which is an analytical process as well as a set of tools to assist in planning and project management oriented towards goals. The results of the program performance index assessment in the case of the pineapple farmer mentoring program carried out by Dompet Dhuafa received a score of 63.26 or an achievement level of 63.29%, this index value is included in the "Developing Program" category. Based on the survey results, the involvement of rural youth in the development of pineapple agriculture is still weak, this is indicated by the data that 78% of rural youth do not work in the agricultural sector, especially pineapple. What is quite interesting about this research is, although most of the rural youth do not work in agriculture, 90% of them still want to live in the village and 72% have a strong desire to be able to work in pineapple farming. Based on the results of stakeholder identification analysis, actors included in the main stakeholder category are Pineapple Farmers, Bandar Nanas, Association of Farmers Groups (Gapoktan), Bandar Nanas, Pineapple Farmer Association and Young Pineapple Farmers. Meanwhile, actors included in the category of supporting stakeholders are the Cijambe District Government, the Cijambe Agriculture Service / PPL, the Cirangkong Village Government, LPMD, BPD, Dompet Dhuafa, Bumdes Aulia Jaya, PT Morelli Makmur and PT Pachira. Results Identification of pineapple farming
Keyword: action strategy, evaluation, pineapple, youth empowerment

Judul: The Development Prospect of Pineapple (Ananas comosus L. Merr.) Based On Land Potency and Financial Feasibility. (case study in Subang, West Java)
Abstrak: Pineapple is a pre-eminent comodity of Subang. Pineapples in SubProvince of Subang are spread in several districts, one of the development center is District of Jalancagak which productivity is 25-35 ton/ha. Such productivity is less than expectation which is 50-60 ton/ha (Official of Agriculture Subang District, 2004). Nevertheless, development of pineapple is one of the alternative way of land exploiting which is more effective and also economically rewarding. The aims of this research are to know the proper areas for pineapple, the economical land use (land rent), and financial feasibility so that the farm activity of pineapple could be developed in Sub-Province of Subang. Land Feasibility Analysis is conducted by using overlay method of secondary datas (land map, solum depth, texture, drainage, and bevel slope), while Financial Feasibility Analysis is obtained by interviewing the farmers on each class of land feasibility.
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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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