Judul: Keanekaragaman Tumbuhan Berguna di Hutan Lindung Gunung Slamet RPH Baturraden, BKPH Gunung Slamet Barat, KPH Banyumas Timur
Abstrak: Protected forest was a forest that had main function as a protective life support system, to managed hydrology system, prevent flooding and erosion, reduce sea water intrusion, and maintained soil fertility. This study aimed to determined the diversity of usefulness plants in protected forests of Slamet Mount RPH Baturraden, BKPH Gunung Slamet Barat, KPH Banyumas Timur. The results of the analysis of vegetation found as many as 130 plant species belonging to 63 families. The most families that found were Euphorbiaceae and habitus were mostly the tree. There were 97% of plants that have the potential for useful plants or as many as 126 species. Potential uses include as food-producing plants, medicinal plants, plants producing construction materials, plants producing rope, webbing, and handicrafts, ornamental plants, plants producing animal feed, plants producer of color, wood-producing plants, plants producing beverages, pesticide-producing plant, plants for traditional rituals and religious purposes, and producing aromatic plants, as well as other uses.
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Judul: Keanekaragaman Tumbuhan Berguna di Taman Hutan Raya KGPAA Mangkunagoro I Jawa Tengah
Abstrak: The Grand Forest Park of KGPAA Mangkunagoro I (TAHURA KGPAA Mangkunagoro I) is an area located in Central Java. This area conserves plant diversity which is potential to be utilized. Research on diversity of useful plants was done because the information about it was not yet available. This research aims to identify the diversity of useful plants at KGPAA Mangkunagoro I Grand Forest Park. The research was conducted by method of vegetation analysis and study of literature. The result of this study shows that 51 species (80,95%) from 63 species was identified as useful plants. Medicinal plant is the group of plants that has the highest number, which is 30 species from 24 families. The most widely used parts of plant were wood (23 species) and leaves (22 species).
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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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