Judul: Simulasi Uji BUSS (Baru, Unik, Seragam, dan Stabil) pada Jambu Biji di Kebun Percobaan PKHT, Pasir Kuda, Bogor
Abstrak: This experiment was conducted to study the Distinctness, Uniformness, and Stability (DUS) of guava varieties, so that the data can be used to verify the Test Implementation Guidelines (PPU) in the DUS test. The experiment was conducted at PKHT experiment station, Pasir Kuda, Bogor. This experiment was conducted using a Complete Randomized Design, one factor with incomplete replications, based on UPOV guidelines. The guava varieties evaluated were Sukun Putih, Variegata, Mutiara, Getas Merah, Kristal, Bangkok, Seedless, Super Red and Sukun Merah. The DUS test simulation results showed that 35 of 40 characteristics were different, it consisting of 3 tree characteristic, 12 leaf characteristic, 3 flower characteristic, 15 fruit characteristic, and 2 recommended characteristic, so can be called as distinctness. The result also showed that no varieties with offtype, so can called as uniform and stabile. We conclude that the verification for the PPU of DUS test is appropriate and can be used for condition in Indonesia, with a few addition of new characters that not written in UPOV guidelines. The results of this research can also be useful to determine the variety of the samples.
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Judul: Simulasi Uji BUSS (Baru, Unik, Seragam, Stabil) Enam Varietas Nenas (Ananas comosus L. Merr.)
Abstrak: The objective of this experiment was to elucidate the characters of the distinctness, uniformity and stability of the six varieties of pineapples, as simulation nDUS test important for the Plant Variety Protection Rights application. The experiment was conducted at Pasir Kuda experimental field, Bogor, West Java. The experimental materials consisted of five candidates varieties are Dole 14, P-1972, Mayan Gold 01, Champaka, Pasir Kuda and Subang as reference variety. The result showed that six varieties can be deemed to be dictinct. The distinctness between candidates varieties with reference variety consist of seven characters on the plant, six characters on the leaves, four characters on the flower, nineteen characters on the peduncle and fruit. Six varieties can be deemed to be uniform and stable. Off-type are found only in one plant with two crown Subang variety. The number of off-types are still under uniformity limits standard.
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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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