Judul: Perbanyakan dengan Stek dan Produksi Tanaman Dandang Gendis ( Clinachantus nutans ) dengan Penggunaan Pupuk Organik.
Abstrak: This research consisted of two experiments. The first experiment aimed to find the number of nodes of stem cutting and organic media to produced plants to be planted in the field. This research used Randomized Complete Block Factorial Design. The second experiment objective was to find the highest shoot production using organic fertilizer. This research used Randomized Complite Block Design. The first experiment used cuttings 2, 3, and 4 nodes and manure treatment i.e : soil mixed with chicken manure, cow manure, chicken manure and rice-hull charcoal, cow manure and rice-hull charcoal 1:1:1 (v/v). The second experiment used chicken manure (10 tons ha -1), cow manure (10 tons ha -1),chicken manure (10 tons ha -1) and rice-hull charcoal (2 tons ha -1), cows manure (10 tons ha -1) and rice-hull charcoal (2 tons ha -1). The results of the first experiment showed that 3 node cuttings is the best treatment for producing plant in the nursery, while in the second experiment cow manure 10 tons ha-1 with rice-hull charcoal 2 tons ha-1 or 10 ton ha-1 chicken manure with rice-hull 2 ton ha-1 produced the highest shoot weight 10 weeks after planting.
Keyword: production, organic fertilizer, nursery, cuttings, Clinacanthus nutans

Judul: Peningkatan Pertumbuhan dan Hasil Tanaman Gedi (Abelmoschus manihot (L.) Medik.) dengan Aplikasi Pupuk Organik dan Pupuk Anorganik
Abstrak: The objective of this research was to study the effect of organic fertilizer and anorganic fertilizer rate to the growth and yield of gedi (Abelmoschus manihot (L.) Medik.). This research was conducted at Cikabayan Farm, Institut Pertanian Bogor, Indonesia from February to August 2011. The material plant was collected from Sorong, West Papua. The experiment was arranged in Completely Randomized Block Design with fertilizer rate as a single factor treatment. There were eight fertilizer rate treatments such as 0, 20, 40, 60 ton.ha−1 organic fertilizer and 0, 20, 40, 60 ton.ha−1 organic fertilizer + NPK. The organic fertilizer was used chicken manure and anorganic fertilizer NPK 15-15-15. The result of this research showed that using 30.39-34.04 ton.ha-1 of organic fertilizer rate will reached the optimum yield. The optimum rate of organic fertilizer + NPK fertilizer was not determined yet. But, by using of NPK fertilizer could increase the harvest.
Keyword: fertilizer dose, gedi, growth, production

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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