Judul: Comparative Analysis of Marketing Channels of Cayenne Pepper through Auction Market and Other Channels in Turi District Sleman Regency
Abstrak: Turi District is one of cayenne pepper production areas in Sleman Regency. The marketing of Cayyene Pepper is interesting to study especially after the chili auction market was established in Sleman Regency in 2018. Therefore, this study aims to compare the marketing of cayenne pepper through the auction market marketing channel with other marketing channels in Sleman Regency based on marketing margin, farmer’s share, and profit ratio to marketing cost. The data collection methods were purposive sampling method applied on farmers and snowball sampling method applied on marketing organization. The results showed that were five kinds of Cayenne Pepper marketing channels in Turi District with two marketing channels through the auction market. The channel through the auction market has a larger sales volume and facilities that make it easier for farmers, such as providing close gathering points and providing production facilities for farmers. Marketing channel through the wholesaler has a higher purchase price at the farmer level than the auction market.
Keyword: Auction Market, Cayenne pepper, Marketing Channels

Judul: Structure of Costs and Income of  Cayenne Pepper Farming in Indonesian
Abstrak: Cabai rawit merupakan salah satu komoditas hortikultura dengan tingkat permintaan yang terus meningkat setiap tahunnya. Perbedaan wilayah, perbedaan dalam pengalokasian penggunaan input, dan perkembangan harga yang memengaruhi pendapatan usahatani cabai rawit. Penelitian ini bertujuan untuk menganalisis keragaan usahatani cabai rawit, struktur biaya, penerimaan hingga pendapatan usahatani cabai rawit. Data yang digunakan yaitu data sekunder yang bersumber Sensus Pertanian 2013: Survei Rumah Tangga Usaha Tanaman Hortikultura Tahun 2014. Jumlah sampel petani cabai rawit sebanyak 4818 petani responden. Metode analisis yang digunakan yaitu analisis struktur biaya, penerimaan, pendapatan, dan R/C ratio usahatani cabai rawit di kedua sentra cabai rawit. Hasil penelitian menunjukkan bahwa biaya tunai dan biaya total serta penerimaan total usahatani di Sumatra Utara lebih besar dibandingkan di Jawa Timur. Usahatani cabai rawit dikedua sentra menguntungkan dengan nilai pendapatan atas biaya tunai, pendapatan atas biaya total, dan nilai R/C ratio., Cayenne pepper is one of the garden crops whose demand is increasing year by year. Regional differences, differences in input use allocation, and price trends affecting income from cayenne pepper cultivation. This study aims to analyze the performance, cost structure, acceptance, and income of cayenne pepper cultivation. The data used is secondary data from the 2013 Agricultural Census: Horticultural Crops Household Survey 2014. The number of samples of cayenne pepper farmers was 4818 respondents. The analytical method used is the analysis of the cost structure, revenue, income, and R/C ratio of cayenne pepper farming in both centers of cayenne pepper. The results showed that the cash costs, total costs, and total income of farming in North Sumatra were greater than those in East Java. Cayenne pepper farming in both centers is profitable with the value of income on cash costs, income on total costs, and the value of the R/C ratio.
Keyword: cayenne pepper, cost structure, 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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