Judul: Pengaruh Jarak Tanam dan Pemupukan Terhadap Pertumbuhan dan Produktivitas Tanaman Torbangun (Coleus amboinicus Lour)
Abstrak: This research was conducted to study the effects of plant spacing and fertilizer on the growth and productivity of Torbangun plant (Coleus amboinicus Lour). The experimental design used in this research was t-test for fertilizer manure: poultry (PA) and cattle (PS). This research was done based on completely randomized design (CRD) with 4 plant spacing treatments 0.5 x 0.5 m (J1), 0.5 x 1 m (J2), 1 x 1 m (J3), 1.5 x 1 m (J4). It is shown that poultry manure significantly resulted in better on the growth and productivity compared to that of cattle manure. Plant spacing significantly affected the variables rate of the increasing number of leaves with poultry manure, production number of leaves with poultry manure in the second period, dry weight of Torbangun leaves with cattle manure in the second period. Plant spacing of 1 x 1 m (J3) and 1 x 1.5 m (J4) was the highest on the growth and productivity of Torbangun plant with the application of either 1 kg poultry manure or cattle manure
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Judul: Pengaruh Pupuk dan Interval Defoliasi terhadap Pertumbuhan dan Produksi Tanaman Torbangun (Coleus amboinicus Lour)
Abstrak: This research was conducted to measure the growth and the production of torbangun. The factors are defoliation rate and organic fertilizer . Defoliation was treated in two levels : once per 6 weeks (D1) and once per 9 weeks (D2). Fertilizer treatments were 100% broiler manure fertilizer (PK 3), 75% broiler manure fertilizer with PSB (Phosphate Solubilizing Bacteria) & AMF (Arbuscula Mycorrhizal Fungi) (PK 2), and 50% broiler manure fertilizer with PSB & AMF (PK 1). Each treatment was replicated for 6 times in 18 weeks. The first defoliation was conducted three times while the second defoliation was conducted twice. The measured variables are leaves amount, canopy height, leaf width, fresh weight of leaves, dried weight of leaves. The results showed that the interaction between PK 3 and D1 had the best effect in the increase of leaves amount. PK 3 and PK 2, individually, gave a good impact to the increase of canopy height. The other results showed that PK 2 gave the best impact to dried leaves weight (p<0.05)
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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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