Judul: Potensi Pengembangan Usaha Ternak Jangkrik di Kelurahan Rangkapanjaya Baru, Kecamatan Pancoran Mas, Kota Depok
Abstrak: Cricket’s farming have potency to be developed as a profitable business. The potency is seen from biological aspects, potency of resources and environmental and also business potency. From the biological point of view, cricket was very efficient, with short live cycle (±70 days) and high egg production (100-250 eggs/cycle). Farmer harvested crickets 6 time every year. Egg’s production of cricket as much as 100-250 eggs with 20% mortality rate. The main component for cricket breeding are breed stock and feed. Breed stock was obtained from breeder and the environment. The parent stock were obtained from the environment has good body resistence. Feed, especially vegetable were obtained from the surrounding environment around the house. Papaya and cassava tree can be found easily in Kelurahan Rangkapanjaya Baru. The cricket’s farming was well accepted by the community. The existence of cricket’s farming can reduce the unemployment in Kelurahan Rangkapanjaya Baru and cricket’s farming doesn’t has any negative impact to the environment. Business potency from cricket’s farming can be seen from the farmer’s income and market potency. The income of farmers received from cricket’s farming were Rp.9.837.705 per year and the economic of scale is 58 box. The biggest cost spent for labor cost as much as 61,09% from total cost. Cricket’s revenue is much to Rp.33.738.435 per year. R/C ratio of cricket’s farming were 1,41. Market potency seen by the trend of cricket’s demand used time series analysis. The result of forecasting of cricket’s demand using equation: Y = 397.646,41 + 15.749,49X – 820,27X2 + 22,04X3 showing cricket’s demand had tendency to increase in the future.
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Judul: Kajian pengembangan usaha budidaya jangkrik sebagai bahan baku industri (studi kasus di Daerah Istimewa Yogyakarta)
Abstrak: Sejak tahun 1998, jangkrik merupakan komoditas pertanian yang semakin diburu setelah diketahui manfaatnya.Budidaya jangkrik menjanjikan pasar yang potensial untuk dibudidayakan. Budidaydbeternak jangkrik memiliki potensi dan peluang pasar yang sangat besar, disamping keuntungan, budidaya jangkrik merupakan usaba mandiri dengan modal yang relatif kecil dan dapat menciptakan lapangan pekejaan. Budidaya jangkrik mudah dikerjakan karena tidak memrlukan keahlian khusus, hanya perlu teIiti dan tekun.
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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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