Judul: Evaluasi Kandungan Nutrien Daun Torbangun (Coleus amboinicus Lour.) Secara in Vitro Terhadap Pengaruh Interval Defoliasi dan Pupuk
Abstrak: Penelitian ini bertujuan untuk mengevaluasi kandungan nutrien daun torbangun secara in vitro terhadap pengaruh interval defoliasi dan penambahan pupuk ayam broiler yang berbeda level. Rancangan percobaan yang digunakan adalah rancangan acak kelompok pola faktorial 3x3 dengan 3 ulangan. Faktor perlakuan meliputi interval defoliasi (6 minggu, 9 minggu dan 12 minggu) dan penambahan level pupuk kandang ayam broiler 100%, 75% dengan FMA+MPF, 50% dengan FMA&MPF. Data dianalisis dengan analisis sidik ragam, perbedaan yang signifikan diuji menggunakan uji lanjut Duncan dengan SPSS. Parameter yang diamati kandungan mineral (P, Fe dan Ca), konsentrasi N-Protein, kecernaan bahan kering dan organik, konsentrasi amonia serta VFA total. Perlakuan interval defoliasi dan pemupukan berpengaruh nyata (P<0.05) terhadap nilai mineral (Fe, Ca dan P) serta kecernaan bahan kering. Perlakuan umur panen 12 minggu berpengaruh nyata (P<0.05) terhadap N-Protein, kecernaan bahan organik dan konsentrasi amonia. Interaksi antar perlakuan berpengaruh terhadap nilai mineral besi, kalsium dan kecernaan bahan kering.
Keyword: Coleus amboinicus L., kecernaan, mineral, pupuk, interval defoliasi

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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