Judul: Resiko pertanian indonesia: persepsi petani terhadap resiko pertanian (studi kasus: petani tanaman pangan di Wilayah Bogor)
Abstrak: Agricultural risks are a serious matter faced by farmers. The objectives of this study were to identify agricultural risks and risks scores at farm households based on the perception of food crop farmers and to develop effective strategies to deal with agricultural risks. The study was conducted from May to September 2011 in Bogor areas. The analysis methods used in this study were qualitative-descriptive, FGD, SWOT, IE and QSPM. The results showed that based on farmers' perceptions, the agricultural risks included production risks, market risks, human risks, institutional risks and financial risks. The highest impact of the risks on farm was the production risk, mainly influenced by pests and diseases. Risk management strategies implemented by farmers were through the use of inputs. Meanwhile, if there was a failure that interfered with family income and the sustainability of farming, farmers would choose to use the income from off-farm work, or to borrow from other parties as a manifestation of risk management strategies. The results of the study also showed that farming activities in Bogor areas were in a stable position. Alternative strategies that need to be considered in coping with agriculture risks were that the government should: (1) be consistent with agricultural policies that had been issued, (2) strengthen the agribusiness development program, (3) encourage investment in agribusiness of food crops subsector, (4) perform the intensification and diversification of agricultural activities, (5) consolidate farmers through institutional development of farmers’ groups and institutional partnership (contract farming), and (6) protect the rights of farmers by legislation and regulation.
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Judul: Manajemen risiko produksi dan penerimaan padi semi organik (Studi : petani gabungan kelompok tani silih asih di Desa Ciburuy, Kec. Cigombong, Kab. Bogor)
Abstrak: Indonesia sebagai negara agraris memiliki potensi pertanian yang mentpakan penyumbang pertumbuhan ekonomi terbesar Indonesia, yaitu sebesar 19,3 persen, terjadi pada triwulan pertama tahun 2009. Preferensi konsumen terhadap pangan yang terbebas dari unsur-unsur kimia yang dapat menyebabkan gangguan kesehatan, menyebabkan pengalihan minat konsumen terhadap produk organik. Petani yang tergabung dalam Gabungan Kelompok Tani Silih Asih memiliki Standar Operasional Prosedur (SOP), dimana input yang digunakan dalam sarana tani mengacu pada pengendalian dan pencegahan hama penyakit melalui pestisida nabati. Proses produksi padi semi organik sangat dipengaruhi iklim kemarau, fluktuasi produktifitas, harga penjualan, dan penerimaan yang mengindikasikan adanya risiko usaha. Penelitian ini bertujuan untuk, (1) mengidentifikasi sumber-sumber risiko produksi dan risiko penerimaan padi semi organik yang terjadi pada petani, (2) menganalisis dampak risiko yang disebabkan oleh sumber-sumber risiko pada kegiatan produksi padi semi organik terhadap petani, dan (3) menganalisis strategi penanganan risiko pada petani yang tergabung dalam Gapoktan Silih Asih.
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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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