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

Judul: Habitat characteristics and population size of black crested macaque (Macaca nigra Desmarest, 1822) in several habitat types in Tangkoko Nature Reserve, North Sulawesi
Abstrak: This study was conducted in Tangkoko Nature Reserve Bitung-North Sulawesi from July to August 2009. The objectives of this study were to identify habitat characteristics of Macaca nigra including physical component, vegetation structure, canopy cover, water availability, food availability, and to assess the population size in Tangkoko Nature Reserve. Vegetation analysis were made in five habitat types including beach forest, primary lowland forest, secondary lowland forest, transitional (ecotone) forest and burned forest. Fifty seven plant species from 29 families including seedling, sapling, pole, and tree were identified during this study. Population size was determined by direct encounter. Trees from family Anacardiaceae, Moraceae, Myrtaceae, Verbenaceae, and Clusiaceae were dominant in study area. The highest Diversity Index was found in lowland transitional forest. Similarity Index shown that every habitat types had little similarity, the biggest similarity index was found between primary forest and transitional (43.10 %). Canopy stratum C (4 - 20 m) was dominant in the study area. The most complex canopy strata were found in primary forest which had canopy stratum A, B, and C. Canopy cover density in the study area was relatively high with more than 85 % except in burned forest with a canopy cover density of 40.73 %. Macaca nigra more active in location with higher canopy cover density than in areas that have less canopy cover density. The cover was used by Macaca nigra for concealment, sleeping, eating, and resting. Five water resources were recorded in Tangkoko Nature Reserve during this study. Macaca nigra used these water resources as drink water sources, bathing places, reducing heat, and as playground areas. Nineteenth plant species were recorded eaten by Macaca nigra and fruit was their primary diet. During the study, nine groups of Macaca nigra were found. Four group (Rambo I, Rambo II, Rambo III, and Pantai Batu) intensively observed to know its population structure, sex ratio, and population size. Population size of these groups was 221 individuals. Based on the analysis with ArcView 3.3, the study site covering an area of 686.456 ha. Group size was 14 – 72 individuals/group. The group density was 0.58 groups/km2 and population density was 32.2 ind/km2. Ecotourism activities, hunting and habitat pressure (forest fire and Ilegal logging) are the main threats for Macaca nigra sustainability.
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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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