Judul: Keragaman morfologi dan pertumbuhan populasi tanaman Phalaenopsis hasil persilangan pada beberapa perlakuan pemupukan dan pemberian Chitosan
Abstrak: Pertumbuhan vegetatif dan generatif tanaman anggrek Phalaenopsis dipengaruhi oleh kondisi lingkungan dan cara budidaya diantaranya dosis pupuk. Penelitian ini bertujuan untuk mengetahui analisis keragaman morfologi dan pengaruh pemupukan dan aplikasi chitosan terhadap pertumbuhan dua populasi anggrek Phalaenopsis hasil persilangan. Penelitian dilaksanakan di Cipanas, kabupaten Cianjur pada bulan Februari hingga Juni 2015. Percobaan ini menggunakan Rancangan Kelompok Lengkap Teracak (RKLT) dengan faktor tunggal yaitu perlakuan pemupukan. Terdapat empat perlakuan yaitu NPK 20:20:20 2 g l-1, NPK 6:20:20 2 g l-1, NPK 20:20:20 2 g l-1 + chitosan 1.5 ppm, dan NPK 6:20:20 2 g l-1 + chitosan 1.5 ppm. Setiap perlakuan terdiri tiga ulangan. Setiap ulangan terdiri dari 5 tanaman. Hasil penelitian menunjukkan bahwa keragaman morfologi pada populasi 1102 dan 1103 membentuk beberapa klaster dengan agglomerative coefficient pada populasi 1102 berada pada jarak euclidius sebesar 0.37 sedangkan populasi 1103 berada pada jarak euclidius sebesar 0.39. Pupuk NPK 20:20:20 2 g l-1 berpengaruh nyata pada panjang daun tanaman anggrek populasi 1102. Perlakuan empat jenis pemupukan termasuk dengan kombinasi chitosan memberikan pengaruh yang sama pada lebar, tebal, dan jumlah daun. Perlakuan NPK 20:20:20 2 g l-1 dan 6:20:20 2 g l-1 pada populasi 1103 menunjukkan presentase tanaman berbunga paling tinggi.
Keyword: Phalaenopsis, fertilization, Chitosan, characterization, flowering

Judul: Karakterisasi Morfologi dan Pertumbuhan Populasi Planlet Anggrek Phalaenopsis Hasil Persilangan Selama Tahap Aklimatisasi
Abstrak: This research was conducted at the Orchids House, KP. Leuwikopo, Bogor from December 2013 until May 2014. This research was conducted to study the morphological character and the effect of leaf fertilizer on growth of hybrid population of Phalaenopsis plantlets. This research consisted of 2 experiments, the first one was morphological characterization and the second was population growth of orchid plantlets. Morphological characterization was conducted according to Balithi guidance for Phalaenopsis characteristic (Balithi 2007). The morphological data was analysed by using NTSYSpc 2.02 version the results were be presented in dendogram. The population growth use a Completely Randomized Factorial Design consisting of two treatments, namely population and leaf fertilizers. The data was analyzed by variance analysis and further testing by DMRT (Duncan Multiple Range Test). The results of data analysis in morphological characterization showed that individuals in the each population has a high of similarity coefficient, which is in population P4 (76-100%), D015 (59- 100%), D022 (78-100%), TSW-1103 (63-100%), and A001 (80-100%). High level of similarity indicates that individuals in the population is relatively uniform for the characters observed. The second experiment showed that fertilizer treatment Supertonik 3 ml l-1 and a combination of fertilizer Supertonik 3 ml l-1 + 3 ppm chitosan increase the number of leaves in the population TSW-1111 (Phal. ‘Timothy Christopher’ x Phal. ‘Leopard Prince’) of 4.60 leaves at 12 weeks after treatment (WAT). Treatment of four types foliar fertilizer composition gives the same number of leaves in the population TSW-1107 (Phal. ‘Taipei Gold’ x Phal. venosa) and populasi TSW-1113 (Phal. Shin Spotted deer siblings cross).
Keyword: foliar fertilizer, growth of planlet, Bogor Agricultural University (IPB), similarity, morphological characterization, acclimatization

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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