Judul: Development of Organic Rice Farming Villages: Consumer and Farmer Perspectives in West Sumatera
Abstrak: Program revolusi hijau berhasil meningkatkan produksi beras Indonesia dan mencapai puncaknya pada tahun 1984 ketika Indonesia mampu mencapai swasembada beras nasional. Namun saat ini kondisi pertanian nasional dihadapkan pada masalah yaitu terjadinya proses degradasi lahan pertanian. Solusi yang ditawarkan permasalahan tersebut, pemerintah membentuk program Pengembangan Desa Pertanian Padi Organik. Meskipun perkembangan pertanian organik di Indonesia masih sangat lambat, namun minat bertani dengan sistem pertanian organik sudah mulai tumbuh. Adanya tantangan dalam pertanian organik di Indonesia menjadi salah satu penyebab masih banyak petani padi konvensional yang enggan beralih ke pertanian organik. Petani cenderung mempertimbangkan apakah usahatani organik lebih menguntungkan dibandingkan usahatani padi konvensional. Tujuan penelitian ini adalah menganalisis willingness to pay konsumen beras organik, membandingkan usahatani padi organik dan konvensional, beras organik dan faktor yang memengaruhi petani mengusahakan padi organik. Penelitian ini menggunakan data primer dari survei 100 konsumen dan 70 petani di Sumatera Barat. Data dianalisis menggunakan Contingent Valuation Method untuk menganalisis willingness to pay. Metode analisis keuntungan usahatani dan Propensity Score Matching digunakan untuk menganalisis perbandingan keuntungan usahatani organik dan konvensional dan metode Regresi Linear Logistic Binary untuk menganalisis faktor yang memengaruhi petani memilih pertanian organik padi. Hasil penelitian menunjukkan bahwa sebanyak 61% responden beras merah ingin membayar beras merah organik dengan harga lebih dibandingkan harga aktual di pasar. Di lain pihak, ada 49% responden beras putih ingin membayar lebih beras putih organik dibandingkan dengan harga aktual beras putih organik di pasar. Rata-rata maksimum willingness to pay konsumen beras organik untuk beras merah sebesar Rp. 36.677 per kg dan beras putih sebesar Rp 20.401 per kg. Hasil penelitian juga menunjukkan bahwa keuntungan rata-rata per hektar per musim tanam usahatani padi organik sebesar Rp. 13.483.586 dan konvensional sebesar Rp. 8.793.891, sedangkan nilai R/C Ratio pertanian organik dan konvensional masing-masing 1,90 dan 1,84. Produksi, keuntungan dan willingness to pay merupakan faktor-faktor memengaruhi keputusan petani dalam memilih usahatani organik. Temuan ini memberikan informasi yang berguna bagi pemerintah dan petani untuk mempertahankan dan melanjutkan usahatani padi organik di Sumatera Barat., The Green Revolution program succeeded in increasing domestic rice production. Indonesia and reached its peak in 1984, when Indonesia was able to achieve national rice self-sufficiency. However, currently, the condition of national agriculture is faced with a problem, namely the process of agricultural land degradation. The solution offered to this problem was that the government form an organic rice farming village development program. Even though the development of organic farming in Indonesia is still very slow, interest in farming using organic farming systems has begun to grow. The challenges of organic farming in Indonesia are one of the reasons why many conventional rice farmers are reluctant to switch to organic farming. Farmers tend to consider whether organic farming is more profitable than conventional rice farming. The aim of this research is to analyze the willingness to pay of organic rice consumers, compare organic and conventional rice farming, and examine the factors that influence farmers to cultivate organic rice. This research uses primary data from a survey of 100 consumers and 70 farmers in West Sumatra. Data analysis uses the Contingent Valuation Method (CVM) analysis method
Keyword: willingness to pay, Beras Organik, Keuntungan, Usahatani

Judul: Income Analysis and Factors Affecting Willingnes to Adopt for SRI Organic Method in Rice Farming (Case Study: Bumi Harapan Village, Wita Ponda Subdistrict, Morowali District, Provinsi Sulawesi Tengah)
Abstrak: Analisis Pendapatan dan Faktor-Faktor yang Memengaruhi Willingnes to Adopt Metode SRI Organik Pada Usahatani Padi (Studi Kasus : Desa Bumi Harapan, Kecamatan Wita Ponda, Kabupaten Morowali, Provinsi Sulawesi Tengah). Dibimbing oleh HASTUTI dan DEA AMANDA. Indonesia mencapai swasembada beras nasional tahun 1984 dengan sistem pertanian konvensional, prestasi tersebut tidak berkelanjutan karena dihadapkan berbagai masalah. Menyikapi permasalahan tersebut, inovasi pertanian padi organik dapat diterapkan. Pertanian Organik berbasis kearifan lokal diperkenalkan untuk pengembangan pertanian organik adalah System of Rice Intensification (SRI) Organik. Tujuan penelitian (1) menganalisis persepsi petani terhadap penggunaan metode SRI Organik, (2) menganalisis perbandingan pendapatan padi Organik dan padi konvensional, (3) menganalisis faktor yang memengaruhi kesediaan adopsi metode SRI Organik. Penelitian ini menggunakan analisis skala Likert untuk mengetahui persepsi petani, analisis pendapatan untuk mengetahui perbandingan pendapatan, dan analisis regresi logistik untuk mengetahui faktor yang memengaruhi kesediaan adopsi. Hasil persepsi penggunaan metode SRI Organik pada petani yang mengadopsi metode SRI Organik yang tertinggi yaitu produksi padi SRI Organik yang lebih tinggi dan sehat, persepsi terendah teknis budidaya SRI organik yang rumit. Persepsi terhadap penggunaan metode SRI Organik pada petani yang belum mengadopsi metode SRI Organik tertinggi yaitu SRI Organik menggunakan pupuk dan pestisida ramah lingkungan, persepsi terendah yaitu ketersediaan tenaga kerja pertanian produktif dan terampil terbatas. Analisis pendapatan menunjukan R/C ratio lebih dari satu artinya usahatani menguntungkan. Faktor yang signifikan memengaruhi petani mengadopsi padi metode SRI Organik yaitu pengalaman, pernah mendapat pelatihan dan status kepemilikan lahan. Kata kunci: pertanian konvensional, regresi logistik, skala likert, usahatani padi, Income Analysis and Factors Affecting Willingnes to Adopt for SRI Organic Method in Rice Farming. (Case Study: Bumi Harapan Village, Wita Ponda Subdistrict, Morowali District, Provinsi Sulawesi Tengah). Supervized by HASTUTI and DEA AMANDA. Indonesia achieving national rice self-sufficiency in 1984 with a conventional farming system, this achievement is not sustainable because it is faced with various problems. In response to these problems, organic rice farming innovations can be applied. Organic agriculture based on local wisdom introduced for the development of organic agriculture is the Organic System of Rice Intensification (SRI). The objectives of the study (1) were to analyze farmers' perceptions of the use of the Organic SRI method, (2) to analyze the income comparison between Organic and conventional rice, (3) to analyze the factors that influenced the willingness to adopt the Organic SRI method. This study uses a Likert scale analysis to determine farmer perceptions, income analysis to determine income comparisons, and logistic regression analysis to determine factors that influence adoption willingness. The results of the perception of the use of the Organic SRI method on farmers who adopt the Organic SRI method are the highest, namely the production of organic SRI rice which is higher and healthier, the lowest perception of complicated organic SRI cultivation techniques. The highest perception of the use of the Organic SRI method in farmers who have not adopted the Organic SRI method is Organic SRI using environmentally friendly fertilizers and pesticides, the lowest perception is that the availability of productive and skilled agricultural labor is limited. Income analysis shows that the R/C ratio is more than one, meaning that
Keyword: Conventional Farming, Logistic Regression, Likert Scale, Lowland Rice

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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