Judul: Evaluasi Kemitraan antara PG Pagottan dengan Petani Tebu di Kabupaten Madiun
Abstrak: Sugar necessary will be increased every year for industry or household necessary. But, the increasing of sugar necessary is not balanced with national production of sugar. One of the alternative to full fill the national sugar needs is business partner. One of the business partner that tied in between Pagottan sugar factory with sugar cane farmer in Madiun regency, East Java. A method of analysis data on this research using farm income analysis, R/C analysis and t-test analysis. Sugar cane farm income analysis showed that revenue over total cost partner farmers more than non-partner farmers. According to R/C ratio showed that with business partner, sugar cane farmer can get profits than farmer non business partner. Whereas, based on the result of t-test show that revenue over total costs per hectare have a significant difference between farmer in business partner and non business partner.
Keyword: t-test, sugarcane, R/C ratio, farm income analysis, business partner

Judul: The Effect of Partnership on Production and Income of Sugarcane Farmers in Malang Regency
Abstrak: Krebet Baru Sugar Factory has entered into a partnership with sugar cane farmers in Malang Regency. Partnerships have a role in technical services and a separate sugarcane purchasing process which causes differences in the production and income of sugarcane farmers. Therefore, this research aims to analyze the effect of partnerships on the production and income of sugar cane farmers in Malang Regency. Respondents in this study were 70 sugar cane farmers consisting of 45 partner sugar cane farmers and 25 non-partner sugar cane farmers with a sampling method, namely random sampling for partner farmers and snowball sampling method for non-partner farmers. The analytical methods used are Income Analysis and Multiple Linear Regression Analysis. The research results show that partnerships do not have a significant effect on the production and income of sugar cane farmers in Malang Regency. However, farmers who enter into partnerships have higher average values for sugarcane production per hectare and income per hectare than farmers who do not enter into partnerships., Pabrik Gula Krebet Baru telah melakukan kemitraan dengan petani tebu di Kabupaten Malang. Kemitraan memiliki peran pada pelayanan teknis dan proses pembelian tebu tersendiri yang menyebabkan perbedaan pada produksi dan pendapatan petani tebu. Oleh karena itu, penelitian ini bertujuan untuk menganalisis pengaruh kemitraan terhadap produksi dan pendapatan petani tebu di Kabupaten Malang. Responden dalam penelitian ini berjumlah 70 petani tebu yang terdiri dari 45 petani tebu mitra dan 25 petani tebu non-mitra dengan metode penentuan sampel yaitu random sampling untuk petani mitra dan metode snowball sampling untuk petani non-mitra. Metode analisis yang digunakan yaitu Analisis Pendapatan dan Analisis Regresi Linier Berganda. Hasil penelitian menunjukkan bahwa kemitraan tidak berpengaruh secara signifikan terhadap produksi dan pendapatan petani tebu di Kabupaten Malang. Selain itu, petani yang melakukan kemitraan memiliki nilai rata-rata yang lebih tinggi pada produksi tebu per hektare dan pendapatan per hektare dibandingkan petani yang tidak melakukan kemitraan.
Keyword: kemitraan, tebu, produksi, pendapatan, regresi linier berganda, partnership, sugar cane, production, income, multiple linier regression

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.
Keyword: