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: Dimensions and Rooting System of Sentang (Melia excelsa Jack.) in Agroforestry Area.
Abstrak: Agroforestri mempunyai dua komponen penyusun utama, yaitu tanaman kehutanan dan tanaman pertanian. Jenis yang dikembangkan di lahan agroforestri diharapkan dapat memberikan manfaat bagi masyarakat yaitu bersifat multifungsi serta memiliki nilai komersial tinggi. Salah satu jenis tanaman yang potensial dikembangkan di lahan agroforestri adalah sentang. Tujuan dari penelitian ini adalah mengetahui pengaruh agroforestri terhadap dimensi dan sistem perakaran tanaman sentang. Penelitian ini menggunakan rancangan acak kelompok lengkap (RAKL) dua faktor dengan enam perlakuan, yaitu sweet sorghum pada jarak tanam 2,5 x 2,5 m; sweet sorghum pada jarak tanam 2,5 x 5 m; grain sorghum pada jarak tanam 2,5 x 2,5 m; grain sorghum pada jarak tanam 2,5 x 5 m; no sorghum pada jarak tanam 2,5 x 2,5 m; no sorghum pada jarak tanam 2,5 x 5 m. Ke enam perlakuan diletakkan dalam tiga blok/ kelompok, yaitu blok 1, 2 dan 3. Dimensi tanaman (diameter pangkal, diameter setinggi dada, tinggi total, tinggi bebas cabang, tinggi tajuk, panjang tajuk, lebar tajuk) memiliki hasil yang hampir sama untuk setiap variabel. Hasil penelitian menunjukkan bahwa, dimensi tanaman terbaik ditemukan pada perlakuan sweet sorghum dan grain sorghum pada ke dua jarak tanam. Sistem perakaran memiliki hasil berbeda untuk setiap variabel. Panjang akar horisontal searah larikan terpendek ditemukan pada perlakuan no sorghum pada jarak tanam 2,5 x 2,5 m, sedangkan untuk kedalamannya yang paling dalam ditemukan pada perlakuan sweet sorghum pada jarak tanam 2,5 x 2,5 m. Panjang akar horisontal tegak lurus larikan terpendek ditemukan pada perlakuan no sorghum pada jarak tanam 2,5 x 5 m, sedangkan untuk kedalamannya yang paling dalam ditemukan pada perlakuan grain sorghum yang ditanam pada jarak tanam 2,5 x 5 m.
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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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