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.
Keyword: 

Judul: Diversity of Useful Plants Species in Protected Areas of PT. Bukit Batu Hutani Alam (PT. BBHA).
Abstrak: Kawasan lindung PT. Bukit Batu Hutani Alam (BBHA) berperan penting bagi kelestarian plasma nutfah tumbuhan, sebagai habitat berbagai spesies satwa dan mempertahankan fungsi-fungsi ekologis kawasan. Informasi mengenai keberadaan flora sangat diperlukan untuk memastikan kelestarian fungsi ekologis kawasan tersebut. Berkaitan dengan hal tersebut maka dilakukan penelitian di kawasan lindung PT. BBHA untuk mengidentifikasi keanekaragaman spesies tumbuhan yang ada dan berguna untuk kehidupan masyarakat. Penelitian dilakukan pada bulan Oktober sampai November 2010. Teknik pengumpulan data yang dilakukan yaitu pengumpulan data sekunder berupa studi literatur dan data primer melalui analisis vegetasi. Metode analisis vegetasi menggunakan kombinasi jalur dan garis berpetak. Pengambilan plot-plot contoh dilakukan pada tiga lokasi yang berbeda, hal ini diharapkan agar data yang didapatkan dapat mewakili kondisi di kawasan lindung tersebut. Hasil penelitian teridentifikasi 38 spesies dari 17 famili yang ditemukan di lokasi penelitian. Dari hasil analisis vegetasi tersebut terdapat beberapa spesies kunci ekosistem gambut seperti Meranti bunga (Shorea teysmanniana Dyer), Meranti batu (Shorea parvifolia Dyer), Mersawa (Anishoptera marginata Korth), Durian burung (Durio carinatus Mast), Dara-dara (Myristica iners Bl), Ramin (Gonystylus bancanus Baill), Kempas (Koompassia malaccensis Maing), Punak (Tetramerista glabra Miq), Resak (Vatica rassak Bl) dan Suntai (Palaquium burckii H.J.L.A.M). Dari 38 spesies tumbuhan tersebut, teridentifikasi 32 spesies tumbuhan berguna (84%) yang dikelompakkan kedalam 10 kelompok kegunaan yaitu tumbuhan obat, hias, aromatik, sumber pangan, sumber pakan ternak, sumber pestisida nabati, sumber pewarna dan tanin, sumber kayu bakar, sumber bahan bangunan dan sumber tali dan kerajinan. Kegunaan tertinggi yaitu untuk sumber bahan bangunan sebanyak 11 spesies dan kemudian diikuti sumber pangan sebanyak 8 spesies.
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: