Judul: The Effect of the Application of Good Agricultural Practices on the Income of White Pepper Farmers with Geographical Indications of Muntok White Pepper
Abstrak: Muntok White Pepper adalah nama Indikasi Geografis bagi lada putih komoditi ekspor unggulan Indonesia yang berasal dari Provinsi Kepulauan Bangka Belitung. Penerapan Indikasi Geografis tersebut dapat diwujudkan apabila lada putih yang dihasilkan petani memenuhi persyaratan standar mutu IG antara lain ukuran, warna, kebersihan, dan kandungan atsiri. Beberapa syarat mutu tersebut hanya terwujud apabila petani menerapkan Good Agricultural Practices. Namun sampai saat ini ternyata hanya sebagian kecil petani yang sudah menerapkan GAP tersebut. Untuk itu maka penelitian ini bertujuan : (1) mendeskripsikan penerapan GAP dan penerapan IG, (2) menganalisis faktor-faktor yang mempengaruhi petani dalam penerapan GAP, (3) menganalisis tingkat penerapan GAP serta faktor-faktor yang mempengaruhi tingkat penerapan GAP dan (4) menganalisis pengaruh penerapan Good Agricultural Practices terhadap pendapatan serta menghitung nilai ekonomi yang dapat dicapai petani di Provinsi Kepulauan Bangka Belitung Penelitian ini menggunakan Data primer cross section yang berasal dari 224 responden, yaitu terdiri dari 142 petani yang menerapkan GAP dan 82 petani non GAP. Penerapan GAP dan IG dianalisis secara deskriptif tabulasi dan Faktorfaktor yang mempengaruhi petani menerapkan GAP Lada dianalisis dengan model regresi logit, faktor-faktor yang mempengaruhi tingkat penerapan GAP Lada dianalisis dengan model tobit, dan pengaruh penerapan GAP terhadap pendapatan petani dianalisis melalui pendekatan propensity score matching (PSM) selanjutnya dihitung potensi nilai ekonomi penerapan GAP di Provinsi Kepulauan Bangka Belitung. Penerapan GAP oleh petani dipengaruhi oleh umur petani, pendidikan petani, pengalaman berusahatani, luas areal panen lada, dan keaktifan petani mengikuti kegiatan sosialisasi. Tingkat Penerapan GAP oleh petani lada putih di Provinsi Kepulauan Bangka Belitung termasuk kategori tinggi. Tingkat penerapan GAP dipengaruhi oleh ketersediaan bibit, luas areal panen lada, umur petani dan pengalaman berusahatani yang dimiliki petani. Penerapan GAP oleh petani lada putih berdampak secara signifikan meningkatkan produktivitas, harga jual dan pendapatan usahatani lada putih. Peningkatan pendapatan didorong oleh meningkatnya produksi dan meningkatnya kualitas lada putih. Keberlanjutan penerapan GAP sangat perlu untuk dilaksanakan dan untuk meningkatkan penerapannya oleh petani lada melalui peningkatan sosialisasi berupa penyuluhan GAP terutama pada kelompok tani yang belum menerapkan. Jika ada keterikatan secara langsung dalam bentuk kontrak kerjasama antara eksportir dengan petani lada putih tentu tingkat penerapan GAP lada putih di tingkat petani dapat terlaksana dengan lebih baik
Keyword: farmer income, propensity score matching, white pepper

Judul: The Impact of Government Policies on Profitability and Competitiveness of White Pepper (Muntok White Pepper) in the Province of Bangka Belitung
Abstrak: Indonesia is well known as the world producer and exporter of white pepper. In the year 2000, Indonesia was able to meet 90 percent of the world demand for white pepper. But during the past 10 years, Indonesia’s white pepper exports have declined, even in 2009 and 2010 export of white pepper contributed only as much as 26.8 percent and 28 percent of the world white pepper demand. At present, the problem becomes a serious threat to the sustainability of white pepper exports as there is a decreasing in crop area thus decline the productivity and a stronger competition with other exporter countries such as Vietnam. This study was conducted in the province of Bangka Belitung. Aims of this study were : (1) to analyze the profitability of white pepper commodity financially and economically, (2) to analyze the comparative and competitive advantages of white pepper, and (3) to analyze the impact of government policy on profitability and competitiveness of white pepper. Policy Analysis Matrix (PAM) was used to calculate the private and social profits and to measure the level of comparative advantage and competitive advantage of white pepper. Sensitivity analysis was also conducted in order to analyze the impact of policy change on white pepper commodity. The results showed that : (1) white pepper farm in the province of Bangka Belitung is profitable (both private and social profitable), (2) it had a competitive advantage (PCR<1) and comparative advantages (DRCR<1 ), and (3) government policies do not provide effective protection for farmers to produce white pepper.
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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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