Judul: Analisis Efisiensi Produksi Tebu Rakyat di Wilayah Kerja PTPN VII Unit Usaha Bungamayang Kabupaten Lampung Utara Propinsi Lampung
Abstrak: The objectives of this study are: (1) to analyze smallholder sugarcane farm system (plant-cane and ratoon cropping patterns) in partnerships that Tebu Rakyat Kredit (TRK-Credit Sugarcane Smallholder partnership) and Tebu Rakyat Bebas (TRB-Independent Sugarcane Smallholder partnership) in the working area of PTPN VII Bungamayang Business Unit and influence partnerships on sugarcane farmers' income levels of sugarcane smallholder, (2) to analyze production efficiency rate on sugarcane smallholders in the working area of PTPN VII Bungamayang Business Unit and influence of partnership on production efficiency on sugarcane smallholders. The results of farm income analysis indicate that smallholder sugarcane farm in the study area on plant-cane and ratoon cropping pattern financially feasible. Farmers' income on ratoon greater than plant-cane cropping pattern and farmers' income on TRK partnership greater than TRB. The estimation results of smallholder sugarcane farms using a frontier production function shows that land, fertilizer (Urea, TSP, KCL), pesticide (solid and liquid) and labour variable have positive significant effect in plant-cane cropping pattern. While land, fertilizer (Urea, TSP, KCL), pesticide (liquid) and labour variable have positive significant effect on ratoon cropping patterns. The technical inefficiency of farmers on plant-cane and ratoon cropping pattern is influenced by education, experience and farm size. Farm size has greatest influence to reducing technical inefficiencies. The partnership has positive influence because it makes farmers efficient technically on plant-cane and ratoon cropping patterns. The farmers have been able to reach allocative and economic efficiency on ratoon but have not on plant-cane cropping patterns. Based on partnership TRB farmers more efficient in technical, allocative and economic efficiency than TRK.
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Judul: The Influence of Land Size and Performance of Partnership Assistance on Sugarcane Farming Income (Case Study of PG Jatitujuh Partner Farmers).
Abstrak: Pabrik Gula Jatitujuh menjalin kemitraan dengan petani di Desa Sumber Kulon. Petani mengelola lahan dengan berbagai luasan. Adanya ketentuan dan pendampingan kemitraan menyebabkan perbedaan pendapatan pada pendapatan petani tebu. Oleh karena itu, penelitian ini bertujuan untuk menganalisis pengaruh luas lahan dan kinerja pendampingan kemitraan terhadap pendapatan. Data yang digunakan adalah data sekunder tahun 2022. Metode analisis yang digunakan yaitu analisis pendapatan, uji anova, analisis regresi linear berganda, analisis standar deviasi, dan koefisien variasi. Hasil penelitian menunjukan bahwa terdapat perbedaan pendapatan pada kelompok luas lahan. Selain itu, kemitraan yang dijalankan oleh PG belum sesuai dengan SOP (Standard Operating Procedure) dari kementrian pertanian., Jatitujuh Sugar Factory has established partnerships with farmers in Sumber Kulon Village. Farmers manage lands of various sizes. The existence of partnership provisions and assistance results in differences in income for sugarcane farmers. Therefore, this study aims to analyze the effect of land area and partnership assistance performance on income. The data used are secondary data from 2022. The analysis methods used are income analysis, ANOVA test, multiple linear regression analysis, standard deviation, and coefficient of variation. The results of the study show that there are differences in income among different land area groups. In addition, the partnerships run by the sugar factory are not in accordance with the Standard Operating Procedure (SOP) of the Ministry of Agriculture.
Keyword: anova, Kinerja, pendapatan, regresi berganda, tebu

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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