Judul: Efisiensi dan Pendapatan Usahatanai Cabai Keriting di Desa Perbawati Kecamatan Sukabumi Kabupaten Sukabumi Jawa Barat
Abstrak: The purposes of this research are to analyze the efficiency of production factors usage and income of curly chili farming. Production function by Cobb- Douglas is used to find out the influence of production factors usage, whereas to find out the income level of red chili farmer in the area of research using scales of income and profit. Result of analysis shows that the land and fungicide labor have significant effect toward curly chili production. Production factors used are not yet achieved to the optimal value so economically curly chili farming at Desa Perbawati is not yet efficient. The result of income calculation and R/C ratio show that curly chili farming at Desa Perbawati is profitable and worth to be cultivated.
Keyword: Bogor Agricultural University (IPB), production factors, curly chili, income, efficiency,

Judul: Analisis pendapatan usahatani cabai merah keriting studi kasus Kelompok Tani Sukatani di Desa Sukamanah Kecamatan Megamendung Kabupaten Bogor
Abstrak: Cabai merah keriting merupakan salah satu komoditi yang memiliki harga yang berfluktuasi. Fluktuasi harga tersebut akan mempengaruhi besarnya pendapatan petani. Penelitian ini dilakukan untuk melihat pendapatan petani cabai merah keriting pada saat harga jual terendah. Metode yang dilakukan pada penelitian ini adalah analisis struktur biaya, analisis pendapatan dan analisis R/C rasio. Dalam analisis pendapatan dilakukan juga analisis balas jasa terhadap seluruh modal, balas jasa terhadap modal petani, dan balas jasa terhadap tenaga kerja keluarga. Hasil penelitian menunjukan bahwa usahatani cabai merah keriting dengan teknologi yang tepat, tetap mendapatkan keuntungan sekalipun dijual dengan harga terendah. Nilai R/C rasio usahatani cabai merah keriting memiliki nilai lebih dari satu, sehingga usahatani ini masih dapat dijalankan oleh petani. tetapi, petani perlu melakukan evaluasi dan perbaikan untuk dapat menggunakan input usahatani secara tepat sehingga usahatani cabai merah keriting ini dapat berjalan secara efektif dan efisien
Keyword: Merah keriting chilli, Income, R/C ratio

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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