Judul: Efisiensi penggunaan input produksi pada pembesaran ikan gurame Osphronemus gouramy di Kecamatan Dramaga Kabupaten Bogor
Abstrak: Bogor Regency especially Dramaga Disrict has a big potencial in gouramy rearing. Unfortunatilly, production factor sach as seed density, feed, sente leaves, manure, and labor were used in no oftimal pattern. Purposive sampling was used in this research which was analized by Cobb Douglas production function method and financial feasibility in gouramy rearing activity. The showed that optimal input were 7 fish/m2 to stock, 2,2851 kg/m2 for pellets, 37,2989 kg/ m2 for sente, 6,6470 kg/ m2 fertilizer, 4,1502 hours/ m2 poud preparation, 8,2186 hours/m2 for maintenance. Analisis gouramy rearing business at optimal conditions reach R/C 1,20, Payback Period 3,2 years, and Break Even Point of 820 kg. Invesment criteria analysis with best scenario is owning land with value a NPV of Rp 517.669.132, Net B/C 3,48 and IRR of 56%. analysis Sensitivity with change Nprice of feed at 16 % indicating that effort still be competent to be run.
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Judul: Optimalisasi input produksi budidaya dalam pendederan ikan gurame Osphronemus gouramy di Desa Petir Kecamatan Dramaga Kabupaten Bogor
Abstrak: Increased production of gurame, especially in the area the Petir Village every year have ups and downs. The purpose of this study to apply the technical production of gurame to optimalization nursery and financial analysis to generate optimal profits. Method used is a case study with intake sample method in the form of purposive sampling. Data Analyse use Cobb-Douglas method and finansial analysys. Estimation of efficiency of input use the optimal input obtained is 42 ekor/m2 for fish seed, 0,525 kg/m2 for urea, 0,021 kg/m2 for lime, 0,915 for postal and 0,329 kg/m2 for flour pellets. Analyse the production of gurame at optimal condition is R/C 1,78, Pay Back Period 0,58 year and break Even Point to Rp 16.605.224 and 11.319 fish seed. Investment analysis criteria with third scenario represent best scenario with value NPV equal to 175.102.279, Net B/C 6,81 and IRR equal to 144 %. Sensitivity analysis by changing the fish seed gurame price by 20% shows that the business is still viable to run.
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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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