Judul: Proses Adopsi Agroforestri Sengon Petani Teh (Studi Kasus di Desa Sukaresmi, Kecamatan Kadupandak, Kabupaten Cianjur, Provinsi Jawa Barat)
Abstrak: Adoption of sengon agroforestry in tea crops of smallholder will influence private forest development and changeover of tea (Camellia sinensis) commodity in Sukaresmi Village. The research aims to know the characteristics and sengon agroforestry management system in tea crops smallholder Sukaresmi Village and how tea smallholder to adopt it. Data were colected from interview, observation, dan literature. Tea leaf productivity at sengon agroforestry is 2861.25 kg/ha/year and tea crops smallholder is 5133.33 kg/ha/year. It caused tea smallholder applied sengon agroforestry in their low productivity tea crops. Sengon agroforestry management system in tea crops smallholder Sukaresmi Village is similar with common private forest. Sengon agroforestry is innovation which diffused through the timber market channel or interactions between community members. The tea smallholder decision adopts sengon agroforestry is optional and generally based on economic consideration.
Keyword: sengon agroforestry, adoption

Judul: Karakteristik Tegakan Hutan Rakyat Sengon di Desa Tonjongsari, Kecamatan Cikalong, Kabupaten Tasikmalaya, Jawa Barat
Abstrak: The high demand for wood industry encouraged the increasing of private forest, particularly in Java. One of the most popular species to be planted is Sengon (Paraserianthes falcataria). The objectives of this study is to determine how about characteristics of the Sengon growing stock of private forest by agroforestry system land cover. The study was carried out in Tonjongsari Village, Cikalong District, Tasikmalaya Residence, West Java Province. Purposivelly sampling with 64 total sample plots were spread evenly in seven hamlets. The characteristics stand curve determined by De Liocourt’s equation or Poisson curve (Husch 2003) and three physical factors (elevation classes, slope classes, and land ownership classes). The results shows that potential of sengon is 112,88 m3/ha obtained in the interval 92.49 m3/ha to 133.27 m3/ha with the SE of 18.06%. Allometric models are formed to describe the shape of farm forest in the Tonjongsari Village is N = (475.4) e-0, 10d. The curve shape resembling the reverse of letter "J" shows that sengon stands in the Tonjongsari village still exhibit properties normally as the uneven-aged natural forests. Chi-square test and twoway ANOVA test based on the physically factors shows that the characteristics of the farm forest stands in the Tonjongsari village strongly influenced by land ownership classes, wich related to differences in the level of economic conditions of the forest farmers. Forest management systems is still based on traditional or local knowledge, handed down from generation to generation by their ancestors. The sustainable yield of sengon stands in Tonjongsari village visible to be developed for supply the row material of wood industry.
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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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