Judul: Analysis on sustainability of organic farming in rice intensification
Abstrak: Indonesia and some other countries in Asia are still striving for food security. This is due to the fact that the world food supply has indicated a critical condition where rice, as the staple food of the majority of Asian population, is one of the critical foods. System of Rice Intensification (SRI) claimed with high productivity and less water requirement might be one of the possible solutions to overcome the world food as well a water crisis. This method has been developed in some Asian countries including Indonesia although some researches still have to be conducted concerning the sustainability of this farming method in increasing rice production. A study was conducted in the District of Sukabumi as a case study with the objective to analyze the potential sustainability of organic rice farming using the SRI method in that area. Study on agricultural sustainability usually concerns with at least three components such as social, economic and environmental aspects. In this study, the three components were stressed on willingness of farmer to adopt new method as social factor, productivity as economic factor and utilization of agricultural wastes for fertilizer as the component that indirectly related to environmental factor. The analyses on the potential agricultural sustainability were conducted based on modeling approach. Several models were developed for uses in the calculation and prediction of the factors considered, which basically were based on Cobb-Douglas production function and Verhulst growth model. The result of this study indicated that the District of Sukabumi had the potential to develop a sustainable organic rice farming using SRI method. However, some factors involving the sustainability still had to be improved for better result of development.
Keyword: Rice production

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: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf