Judul: Analisis keragaman morfologi tanaman manggis (Garcinia Mangostana L.) dari empat sentra produksi di Bali
Abstrak: Mangosteen population has been reported performed apomixis reproduction, lead to assumption genetically homogen. Early studies showed that there were variation among mangosteen population. However the variation could be originated from environment variation. To elucidate genetic variability among mongosteen population in more detail seedling from Purworejo, Purwakarta, Leuwiliang and Trenggalek where grew at same environment in Bogor. The objective of this study is to analysis variability among mangosteen population from Purworejo, Purwakarta, Leuwiliang and Trenggalek. The studies was carried out in the origin of population for morphological character and at Bogor for seedling performance since February 2003 to July 2003. The plant material for this study were ten parent trees from each production centre and ten fruits from each trees, subsequently their seed used for seedling at Bogor. Obtained data analyzed by using homogenity of variance test (Bartlet test) and was continued with Tukey's Studentized Range Test. The plants in seedling were arranged in Completely Randomized Design consisted of four treatment with 10 replications. The result of this study was showed the homogenity variance in leaf weight, leaf area indeks, leaf length, leaf width, fruit weight, seed weight, number of seed. In seedling all character that observed had homogen variance. The analysis of mean morphological character showed that Trenggalek might had the best condition for mangosteen growth. Plant from Trenggalek showed the highest mean in leaf length, leaf width, plant height and number of leaf. All character that observed in seedling had high heritability. Comparison with other study in 2002 and 2001 showed that population had the same result in homogenity variance, was performed that leaf area index, leaf length, leaf width, plant height and number of leaf had homogen variance. It showed that mangosteen population probably had a stable response to enviromental influence
Keyword: apomixis reproduction, Completely Randomized Design, mangosteen population

Judul: Studi keragaman morfologi buah manggis (Garcinia mangostana L.) dari lima lokasi sentra produksi di Pulau Jawa
Abstrak: Mangosteen (Garcinia mangostana L.) is originated from Malaysia which was spread to the South East Asia region including Indonesia. Mangosteen has been reported perform apomixis reproduction, and it is due to mangosteen population in Indonesia presumably genetically homogen. The objective of the study is to evaluate variability pattern on fruit morphologies of mangosteen population from five locations of production center in Java Island, those are Leuwiliang (Bogor), Cantayan (Sukabumi), Wanayasa (Purwakarta), these are on West Java, Kaligesing (Purworejo) on Central Java, and Watulimo (Trenggalek) on East Java. Plant sample was taken 10 trees randomly from each location, subsequently 10 fruit samples taken randomly from each tree. Homogeneity of variance analysis was conducted with Bartlett test and followed with analysis of variance that employed to locul number, fruit weight, fruit length, peduncle length, fruit diameter, fruit length-diameter ratio, rind thickness, Total Soluable Solid (TSS), seed number, and fruit sap. Bartlett test analysis showed that for all of location, no variation was found on fruit weight, fruit length, fruit diameter, fruit length-diameter ratio, rind thickness, Total Soluable Solid (TSS), locul number and seed number, except peduncle length that has variation. Various variance pattern for population on all of location was arised on Total Soluable Solid (TSS), but on fruit diameter, locul number, and seed number the variance pattern were homogenous. Those result tends to assumption that the apomixis reproduction was happening on mangosteen, and if there were variation of fruits performance, its due to variation on environment conditions. These showed by means value of each of character.
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: