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 Role of Farmer Group and Participation of Members  in Hortikultural Farming Development in Pacet District Cianjur Regency
Abstrak: One of the agricultural sub-sectors that has grown a strategic commodity is horticulture. Horticultural Gross Domestic Product (GDP) has an average increase of 4.8% among the highest increases occurring in 2018 which is 7% (BPS, 2018). The increase of horticulture GDP shows horticultural products are a prospective product to be developed and well-received in the market. The development of horticultural farming requires the role of farmer groups as a learning class, a vehicle for cooperation, and a production unit. The development of horticulture farming requires the active participation of members of farmer groups. This study aims to: 1) analyze the perceptions of farmer group members regarding the role of farmer groups toward the horticultural farming development and the factors that influence it; 2) analyze the participation of farmer group members toward horticultural farming development and the factors that influence it; and 3) formulate a strategy to increase the participation of group members toward horticultural farming development. This study used a survey method among two ways of analysis, specifically descriptive and inferential statistics with the path analysis method supported by data in the form of qualitative data. The population was 130 members, with major and intermediate ability classes who attended at least 3 meetings. The number of respondents determination was obtained using the Slovin formula based on the level 95 percent of confidence with a total number of samples was 100 respondents. The determination of respondents in six farmer groups in six villages was carried out using the proportional simple random sampling technique. The results of this study showed that the perception of farmer group members regarding the group's role toward horticultural farming development was quite good, which means that the farmer group was quite capable of carrying out its role properly. The perception of the members in this group was influenced by the outreach activities. The participation of group members was quite good, which means that the farmer groups were quite capable of planning, organizing, implementing, evaluating, and developing group programs. The participation of group members was influenced by the perception of the role of farmer groups, access to information, and length of formal education, while extension activities affected indirectly them. These results were different on the factor of farmer groups involvement which had a negative effect on the member participation. This phenomenon occurred due to the presence of some members in regular farmer group meetings that did not aim to participate in farmer group activities. Hence, there were several efforts to increase farmer participation that required appropriate approaches and strategies in aspects of the role of farmer groups, the utilization of information access, increasing the role of agents of change, and improving the organizing counseling quality.
Keyword: horticultural farming, strategy to increase the participation, the role of farmer groups

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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