Judul: Pengaruh Kombinasi Media Tanam dengan Bobot Umbi Mini terhadap Pertumbuhan Tanaman Taka (Tacca leontopetaloides (Linn.) O. Kuntze)
Abstrak: Tacca (Tacca leontopetaloides (Linn.) O. Kuntze) is an indigenous plant that is widely used for it’s starch. The purpose of this study was to find out the best of combination of planting media with a mini tuber weight for growing tacca. Experiments using Randomized Completely Block Design, two factors and three replications. This research planting media i.e: sand : rice-hull charcoal : cow manure (1:1:1 v/v), soil : sand : cow manure (1:1:1 v/v), soil : rice-hull charcoal : cow manure (1:1:1 v/v), and soil : cow manure (1:1 v/v) with mini-tuber weight of 1-5 and 5.1-20 g. The result showed significant increased vegetative variables i.e: height of plant, number of leaves, leaf area, and widht of canopy and the difference beetwen due to media combination sand : rice-hull charcoal : cow manure (1:1:1 v/v) and soil : rice-hull charcoal : cow manure (1:1:1 v/v). The mini-tuber treatment of 5.1-20 g showed significantly increased vegetative variables i.e: height of plant, leaf area, and widht of canopy, secondary-tuber weight, mother-tuber diameter, secondary-tuber and mother-tuber dense.
Keyword: Tacca leontopetaloides., organic media planting, secondary-tuber, mother-tubeR, mini-tuber

Judul: Pengaruh media, BAP dan pactobutrazol terhadap produksi umbi mini kentang (Solanum tuberosum L.) kultivar red pontiac
Abstrak: Penelitian ini bertujuan untuk menentukan media tumbuh, dosis Benzyl Amin o Purine (BAP) dan Paclobutrazol yang terbaik serta interaksinya terhadap produksi umbi mini kentang kultivar Red Pontiac. Penelitian ini dilakukan di Laboratorium Kultur Jaringan Tanaman PAU Bioteknologi IPB dan kebun percobaan Sub Balai Penelitian Hortikultura Cipanas mulai Februari 1993 sampai Oktober 1993. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok (RAK) faktorial dan non faktorial. Rancangan non faktorial digunakan untuk analisis pengaruh media terhadap persentase hidup (2 MST), tinggi tanaman dan jumlah buku mulai 2 - 4 MST. Sedangkan rancangan faktorial digunakan untuk analisis pengaruh media, Benzyl Amino Purine (BAP) dan Paclobutrazol terhadap: (!.L tinggi tanaman, (2) jumlah buku, (3) jumlah umbi per tanaman, (4) diameter umbi, (5) bobot basah umbi, (6) bobot basah umbi per tanaman, (7) bobot basah umbi per bak, (8) jumlah umbi per bak, (9) Jumlah umbi standar A per tanaman ( :S 1.0 g), (10) jumlah umbi standar B per tanaman (1.0 - 10.0 g), (11) jumlah umbi standar C per tanaman (lebih kurang 10.0 g), (12) bobot kering per umbi dan (13) bobot kering umbi per tanaman mulai 5 - 8 MST. Media pengumbian yang digunakan terdiri dari lima jenis, yaitu: (1) Andisol 100% m,, (2) campuran Andisol dan Margasoil dengan perbandingan 10: 1 (3) campuran Andisol dan Gambut asli dengan perbandingan 5: I = m3, (4) campuran Andisol dan Kompos dengan perbandingan 3 : 1 = m4 dan (5) Kompos l 00 % = ms . Konsentrasi BAP yang diberikan secara eksogen terdiri dari em pat taraf, yaitu : (1) b 1 = 0.0 ppm, (2) b2 = 5.0 ppm, (3) b3 = 10.0 ppm dan (4) b4 = 15.0 ppm. Demikian juga konsentrasi Paclobutrazol terdiri dari empat taraf konsentrasi, yaitu : (!) p1 = 0.0 ppm, (2) p2 = 10.0 ppm, (3) p3 = 20.0 ppm dan (4) p4 = 30.0 ppm. BAP dan Paclobutrazol diberikan hanya satu kali pada saat 4 MST dengan takaran masing-masing 20 ml. Persentase hidup sangat dipengaruhi oleh perlakuan media tumbuh pada 2 MST. Persentase hidup tertinggi diperoleh dari perlakuan media m 1 (Andisol 100%) sejumlah 99.08% dan terendah dari perlakuan media m2 (Andisol : Margasoil = 10 : !) sejumlah 89.54%. Perlakuan media dan paclobutrazol sangat nyata terhadap tinggi tanaman 8 MST. Media kompos 100 % = ms dan p1 = 0.0 ppm paclobutrazol memberikan tinggi tanaman terbaik. Jumlah buku 8 MST sangat dipengaruhi oleh media, paclobutrazol dan interaksi media dengan paclobutrazol. Perlakuam msp3 (Kompos 100 % x 20.0 ppm paclobutrazol) adalah yang terbaik terhadap jumlah buku sebanyak 16.0 buku. ...
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: