Judul: Persamaan Korteweg-de Vries Orde Tinggi untuk Menggambarkan Gerak Gelombang Internal
Abstrak: The ocean can be considered of layers of fluid that each layer has a constant density. Internal waves are waves occur in the interface of every'two layers with different density. Because it occures underneath the surface of the ocean, it is invisible. One of internal waves is internal solitary waves. One of formulation that can describe intemal waves movement is KdV equation. KdV equation is derived from governing equations of ideal fluid in Lagrange formulation using asymptotic method. On this thesis, KdV equation is derived in higher order and then its solution is derived by using internal solitary waves assumption. An example of a two-layer fluid is a case will be used. By using Mathematica6 software, for this case will be obtained the coefficients in lower and higher order explicitly and the corresponding between coefficients and relative lower layer depths and fluid depths, the corresponding between coefficients and relative densities, and also observed the different between solitary waves in lower and higher order.
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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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Judul: Karakteristik Habitat dan Populasi Monyet Butung (Macaca ochreata) di Suaka Margasatwa Tanjung Peropa, Sulawesi Tenggara.
Abstrak: Macaca ochreata merupakan salah satu primata endemik Sulawesi, yang penyebarannya terdapat di Sulawesi Tenggara. Saat ini penelitian mengenai Macaca ochreata masih sangat sedikit, tercatat hanya ada satu penelitian mengenai habitat dan populasi Macaca ochreata di Suaka Margasatwa Tanjung Peropa (SMTP) yang dilakukan 35 tahun yang lalu oleh Bismark (1982) sehingga diperlukan data terbaru mengenai habitat dan populasi Macaca ochreata di SMTP. Karakteristik habitat di identifikasi dengan analisis vegetasi dan dugaan populasi dilakukan menggunakan metode concentration count. Penelitian ini dilakukan pada bulan Februari-Maret 2017 di Blok Hutan Kalobo dengan tujuan untuk mengidentifikasi karakteristik habitat dan menduga populasi Macaca ochreata. Indeks Nilai Penting (INP) tertinggi tingkat pohon yaitu Pangium edule, Artocarpus elastica dan Meliostoma nitida yang merupakan sumber pakan. Terdapat 33 spesies dari 17 famili tumbuhan pakan Macaca ochreata di lokasi penelitian. Macaca ochreata memanfaatkan pohon dengan stratum B dan stratum C. Sebanyak 4 kelompok Macaca ochreata yang ditemui terdiri dari 56 individu dan nilai kepadatan populasi Macaca ochreata sebesar 22,4 ind /km2.
Keyword: Habitat, Macaca ochreata, Populasi, Sulawesi Tenggara