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: Pengaruh Dosis Pupuk Kandang dan Arang Sekam Terhadap Pertumbuhan Tanaman Garut (Maranta arundinacea L.) Di Bawah Naungan Tegakan Sengon [Paraserianthes falcataria (L.) Nielsen]
Abstrak: Garut (Maranta arundinacea L.) was proposed by government as one of food comodities which take priority to be developed and cultivated because it potential as a wheat flour substitute, which is containing alternative sources of carbohydrate. Garut not only used for food, but also for industrial raw materials. Therefor, research about growth of garut plant with different manure doses under shade of P. falcataria stands has been done with the measured parameters are high stems, plant height, diameter, and number of leaves of garut. The design of this experiment using Completely Random Design (CRD) with two factorials. Doses of manure used are 0 gram, 200 gram, 400 gram and 600 gram, and also with the addition of charcoal husk with a 1:1 ratio with the soil. From the results indicate that interaction between manure doses and charcoal husk didn’t give real effect for high stem, diameter, and number of leaves of garut plant, and only gives real impact for plant height. On the parameter number of leaves, although the interaction between manure doses and charcoal husk doesn’t give real effect, but manure doses gives real effect for the number of leaves. Duncan test result showed that 600 gram dose of manure gave a significantly different effect for the number of garut leaves.
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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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