Judul: Pengaruh Jarak Tanam dan Konsentrasi Rootone-F terhadap Kecepatan Penutupan Arachis pintoi Krap. & Greg. pada Pertanaman Cabai (Capsicum annuum L.) Keriting Hibrida
Abstrak: This research was conducted on January until Agustus 2012 at Kebun Percobaan Cikabayan, Darmaga Bogor. Aim of this research is study about plant spacing on A. pintoi, dosage of Rootone - F, and interaction between both treatment to coverage of A. pintoi . Design of this research is Randomized Completely Block Design with 2 factors, plant spacing of A. pintoi (A1: 10 cm x 10 cm dan A2: 15 cm x 15 cm) and dosage of Rootone - F (B1: 0 ppm, B2: 200 ppm, B3: 400 ppm, B4: 600 ppm, dan B5: 800 ppm). Plant spacing A. pintoi in 10 cm x 10 cm has faster coverage than 15 cm x 15 cm. Until 45 days after plant A. pintoi, treatment with higher dosage of Rootone - F has higher coverage percentage. At 600 and 800 ppm dosage of Rootone - F give the best coverage percentage. A. pintoi can compete with weeds effectively at 90 days after plant when percentage of A. pintoi’s coverage higher than 80%. In this research, coverage of A. pintoi in 60 days after planting was critical periode when weeds compete with chilli in vegetative and generative phase. Plant spacing has influence to chili production. At A. pintoi 60 days after planting, plant spacing treatment 15 cm x 15 cm was better in compete and has higher chili production than 10 cm x 10 cm. Dosage of Rootone - F not influencing chili production. Dosage of Rootone - F has not influence to chili production. A. pintoi with higher coverage can compete with weeds especially broad leaf weeds and Cyperus sp.
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Judul: Pengaruh Jarak Tanam dan Jenis Stek Terhadap Kecepatan Penutupan Arachis pintoi Krap. & Greg. Sebagai Biomulsa pada Pertanaman Tomat (Licopersicon esculentum M.)
Abstrak: This research was conducted in Cikabayan Experimental Field, Bogor from December 2011 to May 2012. The objective of this research was to study the effect of different types of cuttings and planting density of Arachis pintoi speed coverage and to find out the effect of the growth and the yield of tomato. The factorial experiment was arrangement in Randomized Completely Block Design with three replication. First factor was the types of cutting (bottom, middle, top) and the second factor was the density of planting (K1: 20 cm x 20 cm; K2:20 cm x 15 cm; K3: 20 cm x 10 cm; K4: 20 cm x 5 cm). The result of this research is that the density of planting and the cuttings factors were significant for increasing the coverage, but the interaction was not significant. K4 and K3 treatment are faster than K2 and K1 treatment on coverage speed. First and second factors were not significant for the growth effect and the yield of tomato. The coverage of Arachis pintoi can reduce the dry weight of weeds and able to increase the fruit weight per plant.
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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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