Judul: Efektivitas Pupuk Organik terhadap Pertumbuhan, Produksi, dan Kadar Hara NPK Daun Jagung Manis di Latosol Darmaga
Abstrak: Sweet corn is seed plant which is commonly planted in Indonesia because of it's sweet taste and contain high carbohydrate. One of the problems in cultivation of sweet corn is low soil fertility, due to the lack of soil nutrient availability and organic matter. To solve that problem can be done by applying organic and anorganic fertilizers. Organic fertilizer is able to increase chemical fertilizer efficiency through improving of physical, chemical and biological of soil. So it is expected to increase the production of plant significantly. The objective of this research is to study the effectiveness of organic fertilizers that was combined with inorganic fertilizer on the growth, production, and N, P, K content of sweet corn leaf in Latosol Darmaga. The field experiment was conducted at the University Farm IPB and plant analisis in the laboratory of soil chemistry and fertility, Department of soil science and Land Resources Faculty of Agriculture IPB. The materials used were organic fertilizers, inorganic fertilizers, seeds of sweet corn (Seleksi Darmaga III), furadan, and agricultural lime. The design of the experiment was a randomized complete block design (RCBD) with a single treatment consisted of 7 treatments which was repeated 3 times each, so there were 21 experimental units. Those seven treatments were: (1) control, (2) Standard (S), (3) 0.5 S + 1.5 PO, (4) 0.5 S + 1 PO, (5) 0.75 S + 1 PO, (6) 1 S + 1 PO and (7) 0.75 S + 1.5 PO. The parameters measured were plant height, production (corn cobs weight including the cornhusk and stover weight), and N-, P-, K-content of corn leaf. The results of this research showed that additional of organic fertilizer with inorganic fertilizer was effective in improving the growth, production, and N, P, K content of sweet corn leaf. The production for treatment 1 S + 1 PO was 14.31 t/ha greater (2.37 t/ha) than standard treatment, and 11.81 t/ha greater than control treatment (no fertilizer application).
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Judul: Efektivitas Pupuk Organik Granul terhadap Pertumbuhan, Produksi dan Kadar Hara NPK Daun Jagung Manis pada Latosol Dramaga
Abstrak: Latosol fertility is generally low due to low nutrient availability and organic matter content, so addition of anorganic fertilizer only will not provide optimal production of plants. Therefore, additional of organic fertilizer must be done. The objective of this research is to study the effectiveness of granulated organic fertilizer which was combined with standard fertilizer on the growth, production, and NPK contents of sweat corn leaves in Latosol Dramaga. The field experiment was conducted in the University Farm IPB, from Februari to August 2012. The nutrient content was analyzed in the Laboratory of Soil chemistry and Fertility, Faculty of Agriculture, IPB. The design of research was completely randomized block design with single factor, that was combination of anorganic fertilizer (standard) with organic fertilizer, which consisted of 7 treatments: control, standard, 50% standard + 100% organic (0,5S+1PO), 50% standard + 150% organic (0,5S+1,5PO), 75% standard + 100% organic (0,75S+1PO), 75% standard + 150% organic (0,75S+1,5PO), and 100% standard + 100% organic (1S+1PO). The result of the research showed that the granulated organic fertilizer increased of growth, production of corn, and nutrient content of corn leaves effectively. The two treatment combinations (1S+1PO) and (0,75S+1PO) showed the best performance, which was indicated by the weight of corn with huskcover and value of RAE i.e. 15,58 t/ha and 162,07% (1S+1PO), and 13,97 t/ha and 128% (0,75S+1PO), respectively. The effect of both treatment combinations above were higher than standard treatment (12,58 t/ha and 100%).
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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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