Judul: Pengelolaan perkebunan sagu (Metroxylon spp) di PT. National Sago Prima, Selat Panjang, Riau: seleksi bibit sagu berdasarkan jenis, tinggi pohon induk dan bobot bibit sagu terhadap pertumbuhan bibit sagu di persemaian
Abstrak: Sago nursery is a special factor that performed during the internship activities at PT. National Sago Prima, Selat Panjang, Riau. The experiment was conducted to obtain information in a nursery on the effects of this type of sago, height of mother plant sago and weight of sucker. The type of sago used was spiny sago (S1) and sago without spiny (S2). Height of mother plant used was 3.3 m - 4.6 m (T1), 4.6 m - 6.6 m (T2), more than 6.6 m (T3) and mother plant that have been harvested (T4). Sucker Weight used was 0,5 kg – 1,5 kg (B1), 2 kg – 3 kg (B2) dan 3,5 kg – 4,5 kg (B3). The results shown sago without spiny is better than spiny sago, height of mother plant is not effect significantly and sucker weight 3,5 kg – 4,5 kg is better than two other sucker weight. During the internship activities, sago cultivation activities conducted to obtain primary data. Secondary data were obtained by conducting interviews, discussions and reading of literature contained in the company.
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Judul: Pengelolaan sagu (Metroxylon spp.) Di PT. National Sago Prima, Selat Panjang, Riau dengan aspek khusus pengaruh bobot bibit dan penggunaan pupuk organik cair terhadap pertumbuhan bibit sistem polibag di pembibitan
Abstrak: The objective of this study was to obtain some informations about sago palm cultivation especially in nursery and know the effect of sucker weight and liquid manure application to the vegetative growth of sago sucker at polybag nursery system. This experiment held in PT. National Sago Prima, Selat Panjang, Riau from February to June 2011. The primary data were found by direct methods, it included the following activities in cultivation of sago palm, and did experiment in the field. The secondary data were found by indirect method, interviewed and discussed with the company staff and study literature to get more informations. The special aspect was find by arranged in split plot design, where the main plot was sucker weight with three levels (50-200 g, 200-500 g, and 500-800 g) and the subplot was four levels of liquid manure application (0, 2, 5, and 8 ml/l) with three replications. The results showed that there was no significantly different in the vegetative growth of sucker by liquid manure application. The sucker weight treatment showed significantly different to survival rate, leaf length, number of leaves, and percentage of expanded leaves. The larger suckers produced higher of leaf length. However, larger suckers didn’t always produce higher percentage of expanded leaves and higher survival rate of suckers in comparison to smaller ones. The sucker weight 200-500 g was the best sucker size to the vegetative growth of suckers
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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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