Judul: Kajian Statistika Terhadap Pertumbuhan dan Kualitas Temulawak
Abstrak: Temulawak (Curcuma xanthorrhiza) is widely used as raw material for traditional medicine regarding the special quality to cure much of disease. The tuber usage has close relationship with contend of active substance. The active substance for every plant is different that is depend on climate, altitude, soil type, treatment, cultivation technique and processing manner. According to the factors, it is necessary to construct an effective and efficiently research design. Factorial experiment with randomized group design was used in this study. The treatment factor are organic fertilizer factor using dosage 0 and 5 ton/ha and inorganic fertilizer factor using dosage 0, 30, 60 and 90 kg/ha. The objectives of the research are to study effect of organic and inorganic fertilizer on growth, production and characteristic compound for temulawak, applying iterated observation method to study growing pattern for temulawak. Statistic study using Manova shows that interaction between organic and inorganic fertilizer is significant for 0.05. The result also indicated that there is an effect of applying organic and without organic fertilizer application on every level inorganic fertilizer. In general, organic and inorganic application will increase the plant high, number of leaf and buds. The average of plant high is 272.667 cm, for leaf number is 36.33 / clump, bud number is 10.67 / clump and production of fresh tuber is 954.7 gr/clump. The result is the highest average that achieved for treatment combination 5 ton/ha of organic fertilizer and 90 kg/ha for inorganic. The iterated observation result shows that both organic and inorganic fertilizer will increasing plant high, leaf and bud number from time to time.
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Judul: Xanthorrhizol Content and Antibacterial Activity of Temulawak (Curcuma xanthorrhiza Roxb.) Cultivated with N, P, and K Fertilizer
Abstrak: Temulawak merupakan tanaman obat yang mengandung senyawa xantorizol yang berkhasiat sebagai antibakteri. Komposisi pupuk yang sesuai meningkatkan produktivitas xantorizol temulawak. Penelitian ini bertujuan menentukan pengaruh pupuk tunggal N, P dan K serta kombinasinya terhadap produktivitas xantorizol dan aktivitas antibakteri dari rimpang temulawak. Terdapat 8 variabel yang diamati; temulawak tanpa pupuk, temulawak dengan pupuk N, P dan K tunggal, kombinasi NP, NK, PK serta NPK. Kandungan xantorizol diukur menggunakan HPLC dan aktivitas antibakteri diuji meggunakan metode difusi cakram. Analisis statistik dilakukan menggunakan uji Anova dan lanjutan dengan uji Duncan pada p < 0,05. Kadar xantorizol tertinggi terkandung pada temulawak dengan kombinasi pupuk PK sebesar 37,56 mg/g DW. Temulawak yang dibudidaya dengan pupuk NPK memiliki kemampuan antibakteri terbaik, dengan zona hambat sebesar 4,65 mm terhadap S. aureus dan 3,64 mm terhadap E. coli. Besarnya zona hambat berbanding lurus dengan kadar xantorizol ekstrak yang diujikan. Hasil penelitian ini dapat dijadikan acuan budidaya temulawak untuk menghasilkan temulawak dengan kadar xantorizol yang tinggi
Keyword: antibakteri, pupuk NPK, temulawak, xantorizol

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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