Judul: Keragaan Agronomi Varietas Padi di Kabupaten Bogor dan Kabupaten Subang Menggunakan Sistem Tanam Jajar Legowo 4:1
Abstrak: Peningkatan produksi padi dapat dilakukan dengan penggunaan varietas unggul didukung oleh sistem budidaya yang tepat dan lingkungan yang sesuai. Lokasi atau lingkungan tumbuh yang berbeda memiliki perbedaan kondisi agroekosistem sehingga dapat menyebabkan pertumbuhan dan produksi yang berbeda pada varietas yang dibudidayakan. Penelitian ini bertujuan mengetahui pengaruh lokasi terhadap keragaan agronomi dan produktivitas beberapa varietas padi yang ditanam menggunakan sistem tanam jajar legowo 4:1. Varietas yang digunakan yaitu Inpari 32, Inpari 33, Inpari 43, IPB 3S, IPB 9G, dan Batang Piaman. Rancangan yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) dengan satu faktor varietas, kemudian dilakukan analisis gabungan antar lokasi percobaan. Lokasi tanam berpengaruh terhadap jumlah anakan, jumlah malai per rumpun, jumlah gabah total per malai, jumlah gabah bernas total per malai, dan bobot gabah kering giling (GKG). Varietas unggul baru (VUB) yang meliputi Inpari 32, Inpari 33, dan Inpari 43 memiliki ciri-ciri jumlah anakan banyak dengan jumlah gabah per malai kategori sedikit dan sedang, sedangkan padi tipe baru (PTB) memiliki ciri-ciri jumlah anakan sedikit dengan jumlah gabah per malai kategori sedang. Jumlah anakan, jumlah malai per rumpun, dan jumlah gabah per malai akan berpengaruh pada produksi padi., The effort for Increasing rice production could be achieved by planting high yielding varieties supported by implementing an appropriate cultivation system and suitable growing environments. Differetnt location or growing environment have different agroecosystem conditions could be differences growth and production of cultivated varieties. This study aimed to determine the effect of different location on agronomic performance and productivity of several rice varieties grown using “jajar legowo 4:1” system. The varieties used were Inpari 32, Inpari 33, Inpari 43, IPB 3S, IPB 9G, and Batang Piaman. It was arranged in Randomized Complete Block Design (RCBD) of one factor, namely variety, then a combined analysis was carried out between the experimental locations. Planting location affected the total stem, total panicle per clump, total grain per panicle, total pithy grain per panicle, and dry milled grain weight (GKG). The new superior varieties (VUB) which include Inpari 32, Inpari 33, and Inpari 43 have the characteristics of a large number of tillers with the number of grain per panicle in the category of few and medium, while the new type of rice (PTB) has the characteristics of a small number of tillers with the number of grain per panicle medium category. The number of tillers, number of panicles per clump, and number of grain per panicle will affect rice production.
Keyword: Agroecosystem, high yielding varieties, productivity

Judul: Rice Growth and Production of Three Varieties of Inpari with Batang Piaman Variety inserts in Multicanopy
Abstrak: Peningkatan jumlah penduduk menyebabkan permintaan akan beras meningkat. Perlu dilaksanakan upaya peningkatan produksi padi untuk memenuhi kebutuhan padi nasional. Pengembangan inovasi sistem budidaya baru melalui sistem multikanopi merupakan salah satu upaya yang dapat dilakukan untuk meningkatkan produksi padi. Penelitian ini bertujuan mengkaji pertumbuhan dan produktivitas padi varietas Inpari 32, Inpari 33, dan Inpari 43 pada sistem budidaya multikanopi dengan sisipan varietas Batang Piaman. Penelitian dilaksanakan di lahan percobaan Balai Besar Tanaman Padi Sukamandi, Subang, Jawa Barat. Rancangan percobaan yang digunakan adalah Rancangan Lengkap Kelompok Teracak (RKLT) Faktorial dua faktor, yaitu varietas (Inpari 32, Inpari 33, dan Inpari 43) dan sistem budidaya (monokultur, multikanopi sisip 1, dan multikanopi sisip 2). Hasil penelitian menunjukkan varietas Inpari 43 dan sistem budidaya monokultur memiliki respon pertumbuhan dan produksi paling baik. Varietas, sistem budidaya, maupun interaksi keduanya tidak mempengaruhi produksi padi dalam gabah kering giling. Berdasarkan proyeksi hasil (tanpa gangguan hama), varietas Inpari 32 dengan sistem budidaya multikanopi sisip 2 menghasilkan produksi gabah kering giling tertinggi sebesar 8,93 ton ha-1., The increase in population caused increasing in demand for rice. It is necessary to increase rice production to meet national rice needs. The development new cultivation through a multi-canopy system is one of the efforts that can be made to increase rice production. This study aims to examine the growth and productivity of rice varieties Inpari 32, Inpari 33, and Inpari 43 in a multi-canopy cultivation system with the insertion of the Batang Piaman variety. The research was carried out in the experimental land of the Sukamandi Rice Research Center, Subang, West Java. The experimental design used was the Complete Design of the Randomized Group (RKLT) Factorial consisted of two factors, namely varieties (Inpari 32, Inpari 33, and Inpari 43) and cultivation systems (monoculture, multi-canopy insert 1, and multi-canopy insert 2). The results showed that the Inpari 43 variety under monoculture cultivation system had the best growth and production response. The variety, cultivation system, or interaction of them do not affect the production of dry milled grain rice. According to the yield projection (no damage by insect), the Inpari 32 variety with a multi-canopy insert 2 cultivation system resulted in the highest production of a dry milled grain of 8.93 tons of hectare.
Keyword: cultivation systems, inserts, production

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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