Judul: Karakterisasi Morfologi dan Agronomi Jarak Pagar (Jatropha curcas L.) Beberapa Aksesi Indonesia Bagian Barat
Abstrak: Morfological and agronomical characterization are important in developing superior varieties of jatropha. In this study, characterization was aimed for analyzing qualitative and quantitative character of 15 accessions from 5 regions in western Indonesia, i.e. Medan, Bengkulu, Banten, Bogor, and Sukabumi. Based on 5 variables, i.e. number of branches, number of productive branches, number of fruits per plant,uniformity of fruits ripening, and time of flowering, there were 3 accessions that have best character. They were Banten I, Bengkulu I, and Sukabumi II. The qualitative characteristic identification showed that qualitative characterization was not influenced by accessions. Based on cluster analysis showed that at 80 % similarity level the 15 accessions could be classified into three main groups. Group I consist of Medan I, Bengkulu I, Bengkulu III, Bengkulu IV, Bogor I, Bogor II, Bogor III, Sukabumi I, Sukabumi II, Sukabumi III, and Sukabumi IV. Group II contain Banten I whereas Medan II, Bengkulu II, and Banten II could be grouped into Group III.
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Judul: Pertumbuhan Beberapa Genotipe Jarak Pagar (Jatropha curcas L.) di Tanah Masam
Abstrak: Indonesia have many acid lands, but their usefullness were still a bit because the nutrient content in acid land is low. Meanwhile, Jatropha is a plant which can grow on various types of lands (includes on marginal land) and has used as raw material for biodiesel. Therefore, the growth of Jatropha need to be study on acid land as an effort for developing Jatropha and usefullness of acid land in Indonesia. To initiate that effort, the research about growing various genotypes Jatropha in acid land was done. The objectives of this research was obtained a potential genotype-tolerant for acid land. The research was conducted at UPTD Technology Development Dryland Singabraja Village, Tenjo Subdistrict, Bogor, West Java, from November 2010 - August 2011. This research using Randomized Complete Design Group (RKLT) with one factor, ie genotype. The result showed that there were differences in growth between the genotypes Jatropha. Generally, there are five genotypes of Jatropha with the best growth in acid land (pH 5.0), ie Medan I-5-1, Dompu, IP-2P-3-4-1, Sulawesi, and Bima M.
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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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