Judul: Ketahan Pangan Rumah Tangga Petani Penghasil Beras Organik
Abstrak: Penelitian ini menggunakan desain Cross Sectional. Populasi dalam penelitian ini adalah rumah tangga peserta Program Pemberdayaan Petani Sehat yang diselenggarakan oleh Lembaga Pertanian Sehat bekerjasama dengan Gabungan Kelompok Tani Silih Asih di Desa Ciburuy, Kecamatan Cigombong, Kabupaten Bogor. Sampel dipilih secara acak dengan ukuran sebesar 61 rumah tangga. Pengumpulan data primer diperoleh melalui wawancara langsung dengan responden yang berpedoman pada kuesioner yang telah dipersiapkan sebelumnya dan telah diujicobakan. Data konsumsi pangan dilakukan dengan cara recall konsumsi pangan 1 X 24 jam, dan food frequency (seminggu, sebulan, dan setahun). Indikator yang digunakan untuk mengukur ketahanan pangan rumah tangga adalah tingkat kecukupan konsumsi energi (TKE). Suatu rumah tangga disebut tahan pangan jika tingkat kecukupan energi = 70%, dan jika < 70% disebut tidak tahan pangan. Untuk melihat hubungan antar peubah digunakan analisis korelasi dan untuk menentukan faktor-faktor determinan dari peubahpeubah bebas yang mempengaruhi ketahanan pangan digunakan analisis regresi lenear berganda.
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Judul: Ketahanan Pangan Rumah Tangga Petani Penghasil Beras Organik
Abstrak: Organic farming is very emphasized in using local input and decreasing external input. Therefore, farmers, who applied organic farming, were expected having a chance to increase their access of food. The study was designed to analyze level of household food security of farmers who yielding organic rice and identify landholding that supporting household food security. For that purposes, 61 samples of household were selected from farming households whose practicing organic farming in Ciburuy Village, Bogor Regency. The gathered data are including data on landholding, working capital, cooperation, education, purposes of practicing on organic farming, wasted management, knowledge of organic farming, organic rice productivity, income, food consumption and level of household food security. Food consumption is recalled in 1 X 24 hours and food frequency (weekly, monthly, and yearly) is used to obtain food consumption data. Household food security was determined based on level of energy consumption. Landholding that supporting household food security is determined based on rice consumption and household productivity. The analyses result of household food security showed that 85.2% of households were secure and 14.8% were insecure. Variables that significantly influenced household food security were income, knowledge of organic farming, organic rice productivity, purposes of practicing on organic farming, landholding, and waste management. Pearson correlation analyses showed that income, knowledge of organic farming, organic rice productivity, and landholding had significant effect toward household food security. Spearman correlation analyses showed that purposes of practicing on organic farming and waste management had significant association with household food security too. Based on daily average of energy sufficiency, land-man ratio should be 318 m2/person.
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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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