Judul: Pengaruh Naungan Sengon (Falcataria moluccana L.) dan Pemupukan terhadap Pertumbuhan Ganyong Putih (Canna edulis Ker.)
Abstrak: Sengon (Falcataria moluccana L.) public forests still becoming custom by Monoculture system. Alternative solution to optimalize the use of land is by agroforestry system. Agroforestry system give income benefits that non timber product. This research is shading influence of sengon and fertilization against white ganyong growth (Canna edulis Ker.). The shading treatments consist of the open area (shade intensity 0%) and sengon shaded area (shade intensity 42%). The fertilizer treatments consist O0 (no fertilizer as control), O1 (POC 350 mL/ha, 450 mL/ha), O2 (POC 700 mL/ha, 900 mL/ha), O3 (POC 1400 mL/ha, 1800 mL/ha) and NPK. The experiment by nested design. The results showed that growth of white ganyong on sengon shaded area is higher than open area to parameters hight of plant, length of leaves, width of leaves and plant biomass. Treatments of shading and fertilization did not significantly effect to tuber wights of white ganyong.
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Judul: Pengaruh Dosis Pupuk NPK dan Kompos terhadap Pertumbuhan Ganyong Merah (Canna edulis Ker.) di bawah Tegakan Sengon (Falcataria moluccana Miq.)
Abstrak: In Indonesia, natural resources have not been maximally utilized yet, so it brought some problems such as food crisis and restricting the conversion of forest-land into agricultural-land. The presence of agroforestry that developing right now could be one of the solution in order to fix the restricting of forest-land conversion problem. Agroforestry of red canna and sengon could be one of the solution. The aim of this study is to determines the influence of NPK and compost fertilizer dose on the growth of canna under sengon stand. NPK fertilizer dose used in this study are 0 g, 1.5 g, 3 g, and 6 g, while the compost fertilizer dose used are 0 g, 50 g, 100 g, 200 g. Experimental design used in this study are complete random sampling (RAL). The result of this study shows that NPK fertilizer dose affected toward the parameter of height, while the dose of compost did not affected the parameters.
Keyword: compost, NPK, Falcataria moluccana, Canna edulis, agroforestry

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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