Judul: Nusantara Superior Teaks (Jati Unggul Nusantara) Growth through Agroforestry system on the Dry Land in Kupang.
Abstrak: Recently, the cultivation of Nusantara Superior Teak (JUN) is mostly done by agroforestry system through seasonal or annual crops. Sorghum Numbu var. is an alternative variety for sorghum development in East Nusa Tenggara and also to meet the food requirements of this area. Based on the land conditions in East Nusa Tenggara, JUN and sorghum Numbu var. are expected to develop through agroforestry systems considering the spacing, water and land conservation needs and technique. Rorak is an alternative method to conserve soil and water due to its capability in holding harvested rain water and also prevention of erosion. This research aims to rewiewing growth and of JUN and sorghum Numbu var. in dry land through agroforesttry system, analyze the effect of rorak and spacing on the growth and productivity of sorghum Numbu var. in dry land through agroforestry system, analyze the effect of rorak and spacing on the rooting system of JUN and sorghum Numbu var. in dry land through agroforestry system. A Two-Factor Experiment in a Randomized Complete Block Design was used with spacing and rorak as factors in 3 blocks. The treatment combinations were 3 x 4 (spacing of 50 cm and non-rorak, spacing of 50 cm and rorak, spacing of 100 cm and rorak, spacing of 100 cm and non-rorak), with a total of 12 experimental units. The data was analyzed using the Statistical Analysis System (SAS) program version 9.1.3 Service Pack 4 in order to obtain diversity analysis. Significant effect of the treatment with Duncan's Multiple Range test. The result of planting distance showed significant effect on diameter and height of sorghum Numbu var. The result of 100 cm spacing showed significant effect on JUN stem diameter, sorghum Numbu var. productivity, weight of 1000 seeds, panicle weight, and sorghum stem diameter. Rorak shows no significant effect on growth and productivity of sorghum Numbu var. The study revealed that, JUN and sorghum Numbu var. can be grown in drylands through agroforestry system. Rorak and spacing were significant with the roots system of teak and shorgum, it is number of roots, length of roots, diameter, broad-surface of roots, and biomass of roots.
Keyword: Agroforestry, dry land, rorak, tectona grandis L., sorghum Numbu var

Judul: The Growth Of Semgon (Falcataria moluccana) at the age of 25 Months and Upland Rice (Oryza sativa) Productivity in an Agroforestry System
Abstrak: Agroforestri merupakan salah satu sistem pemanfaatan lahan dengan mengombinasikan dua atau lebih tanaman guna meningkatkan produktivitas lahan dan melestarikan lingkungan. Kombinasi jenis tanaman yang sering digunakan dalam sistem agroforestri yaitu tanaman sengon dengan padi gogo. Penelitian ini bertujuan untuk menganalisis pertumbuhan sengon umur 25 bulan dan produktivitas padi gogo varietas Rindang 1 dan Rindang 2 Agritan di bawah cekaman naungan sengon. Rancangan penelitian pertumbuhan padi menggunakan rancangan acak lengkap (RAL) faktorial dengan tiga faktor, yaitu pola tanam (monokultur dan agroforestri di setiap tegakan sengon Solomon F1, sengon Solomon F2, dan sengon lokal), metode tanam padi (lubang tanam dengan bambu dan tanpa bambu), dan varietas padi (Rindang 1 dan Rindang 2). Hasil penelitian menunjukkan bahwa pertumbuhan tinggi sengon terbaik ditunjukkan oleh sengon lokal, sedangkan pertumbuhan diameter dan luas tajuk terbaik ditunjukkan oleh sengon Solomon F2. Padi gogo Rindang 1 yang ditanam pada lubang tanam tanpa bambu pada pola tanam monokultur dan agroforestri sengon lokal memiliki produktivitas terbaik yaitu 0,0420 ton ha-1 dan 0,0402 ton ha-1., Agroforestry is a land use system by combining two or more crops to increase land productivity and preserve the environment. The combination of types of plants that are often used in agroforestry systems is sengon with upland rice. This study aimed to analyze the growth of sengon aged 25 months and the productivity of upland rice varieties of Rindang 1 and Rindang 2 Agritan under the stress of sengon shade. The research design for rice growth used a factorial completely randomized design (CRD) with three factors, namely cropping patterns (monoculture and agroforestry in each stand of sengon Solomon F1, sengon Solomon F2, and local sengon), rice planting method (planting holes with bamboo and without bamboo), and upland rice varieties (Rindang 1 and Rindang 2). The results showed that the best growth in height of sengon was shown by local sengon, while the best growth in diameter and canopy area was shown by Solomon F2. Rindang 1 upland rice planted in planting holes without bamboo in monoculture and local sengon agroforestry cropping patterns had the best productivity, namely 0.0420 tons ha-1 and 0.0402 tons ha-1.
Keyword: agroforestry, growth, productivity, sengon, upland 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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