Judul: Pola Pertumbuhan Tanaman dan Penetapan Masak Fisiologis Benih Cabai Katokkon (Capsicum Chinense Jacq.)
Abstrak: Katokkon chilies have a very distinctive aroma and a spiciness level of around 400,000-691,000 SHU or 7 times more spicy than regular chilies. The availability of quality seeds is still low, so efforts are needed to produce high-quality seeds and produce them in large quantities. This study aims to investigate vegetative and generative growth and determine the physiological maturity of Katokkon chili seeds. The research was carried out in two stages, the first stage was observation of vegetative and generative growth of Katokkon chili plants, using simple random sampling with descriptive analysis. The second stage was the determination of the seed physiological maturity which was arranged in nested with a completely randomized design with two factors. The first factor was the fruit position i.e. the first, second, third, and fourth branches. The second factor was the maturity stages nested into the fruit position, which consists of 30 ± 5, 35 ± 5, and 40 ± 5 days after anthesis with 4 replications. The result showed that Katokkon chili grown at an altitude of 1440 m asl began to flower at 45 ± 5 days after planting. Flowers bloom (anthesis) 10 ± 5 days after the appearance of flower buds and develop into ripe red fruits 40 ± 5 days after anthesis. Fruit harvesting can be done every 3 days up to 20 times picking. The number of flowers was around 4 ± 2 per branch and only 50 - 60% developed into fruits Katokkon chili seeds are physiologically matured at 40 ± 5 days after anthesis when the fruit is completely red.
Keyword: anthesis, fruit position, maturity levels, seed viability, seed vigor

Judul: Viabilitas Benih Cabai (Capsicum annuum L.) pada Beberapa Tingkat Kemasakan Buah dan Genotipe
Abstrak: This research used six open pollinated chilli genotypes, namely Anies 1, Anies 2, Seloka 1, Seloka 2, Seloka 3, and SSP were tested in 5 different fruit maturity levels, namely 32, 35, 38, 41, and 44 days after anthesis (DAA). This research used 3 different group of branches, namely the first branches (branches 2-5), second branches (branches 6-7), and third branches (branches 8-9). Physiological maturity is determined by seed viability, vigor and dry seed weight. This study showed the highest values of viability and vigor occured at the level of maturity 44 DAA. The highest viability had germination (DB) on average 84.17% and the highest vigor had vigor index value (IV) on average 20.83%. Germination value was high, and the value of the vigor index was low. Seeds dry weight had started to increase at 38 DAA for all genotypes and remained stable until 44 DAA. The highest seed dry weight indicated that seeds were physiologically mature. Quantitative characters of fruits and seeds were not significantly correlated to the value of IV and DB. The value of IV and DB in first branches was not different with second branches, but most of the quantitative characters of fruits and seeds at first branches were different with second branches.
Keyword: vigor index, seeds, germination, correlation, Branches

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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