Judul: Pengaruh Pupuk Organik Guano dan Chitosan terhadap Pertumbuhan dan Perkembangan Anggrek Phalaenopsis spp.
Abstrak: This research was conducted to determine the effect of organic fertilizer guano and chitosan on the growth and development of phalaenopsis orchid conducted in the Gunung Batu nursery, Bogor in March until August 2011. This research used a completely randomized block design with 4 treatments and 4 replications. Fertilizer treatments consisted of Thaichung fertilizer 1 g /l, Thaichung fertilizer 1 g/l + chitosan 10 ppm, Thaichung fertilizer 1 g/l + guano 10 ml / l, and Thaichung fertilizer 1 g/l + chitosan 10 ppm + guano 10 ml / l. Thaichung fertilizer 1 g/l were needed for P. bellina and P. modesta, and guano 10 ml/l were needed for P. amabilis in compot in the hot and dry conditions.
Keyword: 

Judul: Pertumbuhan Anggrek Phalaenopsis amabilis pada Perlakuan Chitosan dan Asam Salisila
Abstrak: Phalaenopsis orchid plant vegetative growth is influenced by environmental condition such as light, temperature, and humidity. Certain organic material affected on the growth, development and plant resistance to pests and diseases, including chitosan and salicylic acid. The objective of this research was to test the application of organic compound chitosan and salicylic acid on the growth of Phalaenopsis amabilis. This research was arranged in a randomized completely design with organic compound as a single factor. There were six treatment, 3 ppm chitosan, chitosan 6 ppm, 5 ppm salicylic acid, salicylic acid 10 ppm and 3 ppm chitosan + 5 ppm salicylic acid. Each treatment was repeated five times with 3 plantlets per bottle. Organic compound were mixed in ½ MS in vitro medium and planlets were transfered to the treatment medium and cultured in the tissue culture laboratory for four weeks. Planlets subsequently were acclimatizated to spaghnum ii moss medium in greenhouse. Treatment were continued by spraying of organic compound to planlets every two weeks. The results of the experiment showed that the best treatment of organic compound, was chitosan 3 ppm. This is showed by length of youngest leaf and percentage growth of plant on treatment of chitosan 3 ppm.
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: