Judul: Pengaruh Pemberian Pupuk N Dengan Berbagai Dosis Terhadap Pertumbuhan Awal Bibit Sagu (Metroxylon spp.) di Persemaian Dengan Sistem Polibag
Abstrak: Percobaan ini dilakukan untuk mengetahui pengaruh berbagai dosis pupuk N terhadap pertumbuhan awal bibit sagu di persemaian dengan sistem polibag. Percobaan dilaksanakan di PT. National Sago Prima, Selat Panjang Kabupaten Kepulauan Meranti Provinsi Riau pada bulan Februari sampai Juni 2012. Percobaan menggunakan rancangan acak kelompok dengan satu faktor yaitu dosis N. Terdapat enam taraf perlakuan dosis N, yaitu 0, 3, 6, 9, 12 dan 15 g N/polibag. Setiap perlakuan diulang sebanyak empat kali, sehingga terdapat 24 satuan percobaan. Masing-masing satuan percobaan menggunakan 50 bibit, sehingga total bibit yang ditanam sebanyak 1200. Setiap satuan percobaan terdapat 24 bibit yang diamati, sehingga total yang diamati adalah 756 bibit. Bibit yang digunakan memiliki bobot 0.5-1.0 kg. Sebelum ditanam, bibit dipangkas 20 cm dari pangkal banir dan dibersihkan, kemudian direndam dengan larutan Dithane M-45 selama 10 menit. Bibit yang sudah direndam di tanam ke polibag dengan media tanah gambut. Saat penanaman diberikan furadan dengan dosis 3-5 g/polibag.
Keyword: 

Judul: Pengaruh Pemberian Pupuk P dengan Berbagai Dosis terhadap Pertumbuhan Awal Bibit Sagu di Persemaian dengan Sistem Polibag
Abstrak: Experiment was conducted at PT. National Sago Prima, Selat Panjang, Riau. It was conducted during five months from February to June 2012. The purpose of this experiment was to study the effect of P fertilizer and look for a doses of P fertilizer that give the best results of early growth of sago sucker in nursery by polybag system. The experiment used Complete Randomized Block Design with a single factor consisted of 6 treatment and 4 replications. Treatment given the level of P fertilizer with 0, 3, 6, 9, 12, and 15 g TSP/polybag (equivalent to 0, 1.82, 3.64, 5.46, 7.28, 9.10 g P2O5/polibag). N and K Fertilizer use as basal fertilizer dose of 6 g each Urea/polybag and 2.5 g KCl/polybag. The experiment results show that P fertilization with different doses are not significantly affect for all vegetative variables (early growth) observed sago seeds which includes survival persentage, percentage of leaf expansion, leaf length pruning, length and width of the leaf pruning, leaf length 1, length and width of the leaf 1, leaf length of petiol 1, the number of child leaf 1, leaf leaves live span 1, the total number of leaves, dry weight of roots, petiol and rachis. Luxury consumption occurs due to the addition of P fertilizer caused the P nutrient medium prior to fertilization considered very high. Early growth of sago sucker are still influenced by the nutrition in the basal of sucker and environment.
Keyword: 

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.
Keyword: