Judul: Pengaruh Pohon Penaung Leda (Eucalyptus deglupta Bl.) dan Suren (Toona sureni Merr.) terhadap Pertumbuhan dan Produksi Kopi (Coffea arabica L.)
Abstrak: Agroforestry of coffee in Perum Perhutani BKPH Banjaran, KPH Bandung Selatan was established. Coffee were planted under E. deglupta and T. sureni. The difference of species shade tree may give influence on the growth and production of coffee. The purpose of this research was to compare the influence of shade tree E. deglupta and T. Sureni on the growth and production of coffee (C. arabica). The growth parameters of coffee consisting of diameter and height, while the production parameters of coffee consisting of productive branch, bunches of branch, fruit of bunches, and coffee cherries weight. The result of ttest showed that diameter of coffee was not significantly different. Height of coffee was significantly affected by the species of shade tree. The average height coffee under T. Sureni (170.58 cm) greater than the height coffee under E. deglupta (151.56 cm). However, leda provide better coffee production compared to suren. Based on the result of t-test, the number of productive branches and coffee cherries weight have significantly different values. The number of productive branches and coffee cherries weight under leda bigger than coffee under suren. Production of coffee under leda (3 127.17 kg/ha) greater than suren (1 173.74 kg/ha).
Keyword: Bogor Agricultural University (IPB), shade tree, production, growth, agroforestry of coffee

Judul: Pengaruh Teras Bangku dengan Penguat Teras terhadap Kualitas Lingkungan Tumbuh, Pertumbuhan dan Produktivitas Kopi Arabika
Abstrak: Tujuan penelitian ini adalah untuk (1) mengetahui pengaruh kombinasi terns bangku dan tanaman penguat terns terhadap kualitas air limpasan, dan (2) mengetahui kombinasi pengaruh terns bangku dan tanaman penguat terns terhadap volume air limpasan, erosi, status hara tanah, biologi tanah, status hara tanaman kopi Arabika, pertumbuhan dan produktivitas tanaman kopi Arnbika. Penelitian ini menggunakan petak-petak berukurnn 2 m x 22 m yang disusun berdasarkan Rancangan Acak Kelompok Lengkap, dengan lima perlakuan dan empat ulangan. Perlakuan yang diuji adalah (a) Kontrol, tanpa terns dan tanpa tanaman penguat terns; (b) Terns bangku tanpa tanaman penguat terns; (c) Terns bangku dengan tanaman penguat terns Vetiveria zizanioides; (d) Terns bangku dengan tanaman penguat terns Moghania macrophylla; dan (e) Terns bangku dengan tanaman penguat terns Leucaena leucocephala. Kualitas air limpasan, volume air limpasan, dan erosi diperoleh dengan simulasi hujan yang dilakukan sebelum dan setelah pemupukan dengan intensitas 22 mm selama 30 menit. Rataan dibandingkan dengan uj i kontras ortogonal. dst ...
Keyword: Teras Bangku, Produktivitas, Kopi Arabika

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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