Judul: Income Analysis And Efficiency Of Carrot Farming In Pagar Wangi Urban Village, Dempo Utara Sub-District, Pagar Alam City
Abstrak: Kelurahan Pagar Wangi merupakan sentra produksi wortel di Kota Pagar Alam. Kelurahan Pagar Wangi adalah daerah dengan produksi dan luas lahan wortel terbesar. Dalam melakukan usahataninya, alokasi input yang digunakan masih belum sesuai dengan input optimal. Penelitian ini bertujuan untuk (1) menganalisis pendapatan usahatani wortel di Kelurahan Pagar Wangi, (2) menganalisis faktor-faktor yang memengaruhi produktivitas, (3) menganalisis efisiensi ekonomi. Penelitian ini menggunakan R/C ratio untuk mengetahui keuntungan usahatani wortel, fungsi produksi Cobb-Douglass dengan estimasi Ordinary Least Squares (OLS) untuk menganalisis faktor produksi yang memengaruhi produktivitas, dan metode Nilai Produk Marginal (NPM) untuk mengetahui efisiensi ekonomi. Hasil penelitian menunjukkan bahwa nilai R/C ratio usahatani wortel di Kelurahan Pagar Wangi masih menguntungkan walaupun belum optimal. Faktor-faktor yang berpengaruh signifikan terhadap produktivitas usahatani wortel adalah benih, pupuk kandang, dan pupuk NPK. Faktor produksi yang belum efisien pada usahatani wortel yaitu benih sehingga perlu untuk ditambah. Selanjutnya, faktor produksi yang tidak efisien yaitu pupuk kandang dan pupuk NPK sehingga perlu untuk dikurangi., Center of carrot production in Pagar Alam City is Pagar Wangi Urban Village. Pagar Wangi Urban Village is the area with the largest carrot land and amount of production. The allocation of inputs used in farming is still not in line with the most optimal input. The research aim to (1) analyze the income of carrot farming in Pagar Wangi Urban Village, (2) analyze the factors that affect the productivity, (3) analyze the economic efficiency. This research uses the R/C ratio to determine the benefits of carrot farming, the Cobb-Douglass Production function with Ordinary Least Squares (OLS) estimation to analyze the factors that affect the productivity, and the Value Marginal Product (VMP) to determine the economic efficiency. The results showed that the R/C value of the carrot farming in Pagar Wangi Urban Village is still profitable although not optimal. The factors that had a significant effect on the productivity of carrot farming was seeds, animal manure, and NPK fertilizer. Input that are not efficient yet in carrot farming are seeds so they need to be added. Furthermore, the inefficienct input in carrot farming are NPK fertilizer and animal manure so they need to be reduced.
Keyword: income analysis, OLS, productivity, R/C ratio, VMP

Judul: Analisis Efisiensi Ekonomi Usahatani Tumpangsari Wortel di Desa Sukatani, Kecamatan Pacet, Kabupaten Cianjur
Abstrak: The agricultural sector is one sector which is still reliable, because it has an important role for the economic development of a nation. Based on the value of 2007-2010 Indonesian horticulture Gross Domestic Product (GDP), vegetables are the second largest contributor to GDP after fruit with average value of Rp 28,885 billion. One type of vegetable that has the greatest growth rate is carrots, with growth rate 5.05%. Carrot production in Indonesia from 2007-2010 tended to increase. Largest carrot production is from Cianjur with the amount of 34 559 tones, equivalent to 30.43% of the total production in West Java and also become the center of production of carrots. The purpose of this study was to identify the factors that affect the level of production and estimate the production of economic efficiency. The model analysis used in this study was Cobb Douglas function model with Ordinary Least Square method (OLS). Economic efficiency analysis performed using the ratio approach Marginal Product Value (NPM) with Sacrifice Marginal Cost (BKM). The analysis showed that the factors which significantly affect the influence the farm production of intercropping of carrots were seeds, organic fertilizer and urea fertilizer. Results of economic efficiency analysis showed that farming had not reached economic efficiency yet. It was shown from the ratio of the Marginal Product Value (NPM) with sacrifices Marginal Cost (BKM) were not equal with one. Based on the income analysis, intercropping farming of carrots was providing economic benefits for farmers. This was indicated by the value of the cash cost of revenues over one growing season was Rp 10 747 174.00/Ha and revenues over one growing season total cost was Rp 3 592 374.00/Ha.
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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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