Judul: Characterization and evaluation of doubled haploid upland rice lines obtained from anther culture to shade tolerance
Abstrak: Pengembangan budidaya padi gogo sebagai tanaman tumpangsari atau tanaman sela memerlukan penggunaan varietas unggul toleran naungan. Perakitan padi gogo unggul toleran naungan dalam waktu yang relatif cepat dapat dilakukan melalui teknik kultur antera., The development of upland rice cultivation as multiple cropping plant requires the use of high yielding shading-tolerant rice varieties. The breeding of high yield shading-tolerant rice varieties. The breeding of high yield shading-tolerant upland rice in relatively short time can be done by using another culture technique. The technique has been recognized as rapid and efficient technology at plant improvement.
Keyword: 

Judul: Produksi Tanaman Dihaploid dari Persilangan Padi Sawah dan Padi Gogo melalui Kultur Antera
Abstrak: Anther culture is one of rice breeding method which is efficient in time, cost and labor. Conventional rice breeding usually needs 10 generations to achieve homozigous pure lines. Anther culture can reduce the time to only 1-2 generations. The objective of this research was to obtain doubled haploid or dihaploid plants (DH0) produced from rice anther culture of F1. The materials used in this research were anthers of F1 from some lowland rice and upland rice crosses i.e 1) IR85640-114-2-1-3 x I5-10-1-1, 2) Bio-R81 x I5-10-1-1, 3) Bio-R81 x O18b-1 and 4) Bio-R82-2 x O18b-1. The result from this research were 265 green plants (34% from the total plants) consisted of 34 green plants from (IR85640-114-2-1-3 x I5-10-1-1) , 59 green plants from (Bio-R81 x I5-10-1-1), 77 green plants from (Bio-R81 x O18b-1) , and 95 green plants from (Bio-R82-2 x O18b-1). The green plants were acclimatized, grown in the greenhouse and selected to obtain first generation of dihaploid plants. This research yielded 15, 11, 21, and 26 doubled-haploid (DH0) lines from IR85640-114-2-1-3 x I5-10-1-1, Bio-R81 x I5-10-1-1, Bio-R81 x O18b-1, and Bio-R82-2 x O18b-1 respectively.
Keyword: upland rice, lowland rice, new lines

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: