Judul: Pengaruh Jenis Media Tanam terhadap Pertumbuhan Bibit Pepaya (Carica papaya L.) Genotipe IPB 3, IPB 4, dan IPB 9.
Abstrak: The research aims to study the influence of growing media types on seed germination and seedlings growth of papaya IPB 3, IPB 4 and IPB 9 genotypes and know growing medium suitable for growth of papaya seedlings is good and has a light weight to facilitate the transportation of seedlings. The research was conducted in March until September 2011 in the greenhouse FATETA IPB, Leuwikopo Bogor and The Experimental Garden of PKBT IPB, Tajur Bogor. The design used was Randomized Complete Design Group two factors. The first factor is the growing media with 5 kinds with the same ratio (2:1:1), namely M1 = soil: sand: manure, M2 = soil: sand: rice husk charcoal, M3 = soil: sand: cocopeat, M4 = soil: manure: cocopeat, and M5 = soil: manure: rice husk charcoal. The experiment consisted of 15 combinations with 3 replicates then there were 45 experimental units . The results showed that papaya seeds germinate is the highest of the growing media mix of soil, manure, and rice husk charcoal (M5) is 70% and IPB 3 genotype (G1) is 70.91%. The composition of media soil, manure, and rice husk charcoal (M5) with a ratio of 2:1:1 is the best medium for papaya seedlings at 6 MST and has a weight of seedlings per polybag is the lightest compared with other growing media to facilitate the transportation of seedlings.
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Judul: Pengaruh Komposisi Media Tanam Terhadap Bibit dan Pertumbuhan Awal Pepaya (Carica papaya L.) Tipe Bangkok dan California.
Abstrak: The objective of the research was to observed growing media with a light weight but still could support the seedling and initial growth of two types of papaya. The research was conducted at Cikabayan Experimental Field, Darmaga, Bogor, from May to October 2013. The experiments used two papaya types which were Bangkok and California and was arranged in Factorial Randomized Complete Block Design with one factor and three replications. The treatment was growing media composition which were a mix of soil, cattle manure, and rice husk charcoal with different ratio (ratio based on volume); M1 (2 :1:1) as a control, M2 (1:1:1), M3 (1:1:2), M4 (1:2:1), M5 (1:2:2), M6 (2:1:2), and M7 (2:2:1). The result showed that the growing media affected the weight of seedling and diameter of stem by the polybag of both types in the seedling phase at 5 Weeks After Planting (WAP), and also affected the height of plant at 1 and 2 WAP of Bangkok type. Growing media thas has light weight and was able to support the seedling’s growth was media M3, M4, and M5 for both Bangkok and California types, while the most economical was media M3. The composition of soil in the growing media can be reduced to only 1/5 part from the total volume of the media without inhibit the growth of the seedling. Growing media composition did not affected the height, number of leaf, diameter of stem, time of first flowering and height of the first flower bud in both Bangkok and California types in the field.
Keyword: cattle manure, economical, lighter media, rice husk charcoal

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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