Judul: Analisis Total Factor Productivity (Tfp) Tanaman Perkebunan Di Indonesia Periode 1990-2010
Abstrak: Tujuan penelitian ini adalah untuk menganalis Total Factor Productivity (TFP) tanaman perkebunan di Indonesia periode 1990-2010 dengan menggunakan Indeks Tornqvist-Theil. Selain itu untuk melihat pengaruh input produksi terhadap output produksi tanaman perkebunan di Indonesia, metode yang digunakan adalah OLS (Ordinary Least Square) dengan model fungsi Cobb-Douglass. Hasil penelitian menunjukan bahwa Indeks TFP pada tanaman perkebunan di Indonesia periode 1990-2010 bernilai positif. Hal ini menandakan bahwa penggunaan input dan output dapat dihasilkan secara maksimal. Hasil estimasi dari fungsi Cobb- Douglass untuk melihat pengaruh input terhadap output produksi menunjukan bahwa seluruh penggunaan input seperti kapital, tenaga kerja, dan luas panen berpengaruh secara positif dan signifikan terhadap output produksi.
Keyword: Indeks Tornqvist-Theil, Tanaman perkebunan Indonesia, Total Factor Productivity.

Judul: Analisis Faktor-Faktor yang Memengaruhi Pertumbuhan Total Factor Productivity (TFP) Sektor Pertanian di Indonesia
Abstrak: The agricultural sector is a sector which is crucial and has an important role for people life. Enhancement in agricultural productivity is the focus of the current Government. Previous research shows that the growth of agricultural output was not only influenced by the capital and labor but there is another factor called Total Factor Productivity (TFP). This research focuses on the factors that affect TFP growth of the agricultural sector in Indonesia in the period 1980-2011. This research using Cobb-Douglas linearization to calculate TFP value. Error Correction Model (ECM) used to analyze factors that affect agricultural TFP. Independent variables used in this model are irrigation, inflation rate, level of education, agricultural credit, and trade openness, while the dependent variable used is agricultural TFP. The results of this research indicate that the variables that affect agricultural TFP in the short-term are education and level of trade openness. Variables that affect agricultural TFP on long term are the level of education, agricultural credit, and trade openness.
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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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