Judul: Daily Activities and Welfare Rate Agile Gibbon (Hylobates agilis) at Schmutzer Primates Center, Ragunan Zoo
Abstrak: Keberadaan ungko sebagai salah satu jenis satwa yang dilindungi semakin menurun populasinya akibat perburuan dan hilangnya habitat. Salah satu upaya konservasi ungko dilakukan secara ex-situ di kebun binatang. Penelitian ini bertujuan untuk mengidentifikasi aktivitas harian, mengidentifikasi manajemen pemeliharaan dan mengukur tingkat kesejahteraan ungko. Metode yang digunakan meliputi observasi langsung dan wawancara kepada pengelola serta studi literatur. Hasil penelitian menunjukkan aktivitas yang paling banyak dilakukan oleh ungko jantan yaitu istirahat sebesar 29,33%, bergerak 25,33%, menelisik 20%, makan 14% dan main 11,33%. Sedangkan ungko betina lebih banyak melakukan aktivitas istirahat dengan persentase sebesar 31,69% yang diikuti dengan aktivitas menelisik 29,23%, bergerak 21,31%, makan 11,20% dan bermain 6,56%. Ukuran kandang ungko yang ada di PPS telah memenuhi standar NSW Agriculture sehingga ungko dapat bebas bergerak. Pakan yang diberikan telah memenuhi kebutuhan ungko. Pengelolaan kesejahteraan ungko di PPS dilakukan dengan sangat baik. Pencapaian implementasi kesejahteraan ungko di PPS memiliki nilai sebesar 81,50 yang termasuk dalam kategori sangat baik.
Keyword: agile gibbon, daily activities, maintenance management, welfare rate

Judul: Aktivitas Makan dan Status Gizi Owa Jawa (Hylobates moloch) di Pusat Primata Schmutzer Taman Margasatwa Ragunan Jakarta
Abstrak: Hylobates moloch is endemic Indonesian primate which live in Java. The population of javan gibbon is declining because of the loss of feeds due to the degradation of habitats. This research aims to identify feeding activities, type of feeds, and nutrient status of javan gibbon (Hylobates moloch) in Schmutzer Primate Centre Ragunan Zoo Jakarta. Feeding activities observation was performed using focal animal sampling method which done in the same time with feed palatability. Feeds were given once a day which consist of fruits, vegetables, eggs, and bread. Highest feeding activities was recorded in the feeding given by zoo keeper. Biting and swallowing are the highest was shown Kecil (juvenile) feeding activities of first cage (22.00%). Highest feeding activity in second cage made by Rano (male) was chewing (21.43%) and in the third cage was carried out by Eneng (female) which were biting, chewing, and swallowing each 23.31%. Based on the palatability rank in the three cages, kumak (Lactuca indica) and banana (Musa paradisiaca) was categorized as the most favored feed. Based on the nutrient status, it was obtained that dry materials were consumed 683,83 to 1099,03 g/cage/day, protein consumption 13,13 to 19,37 g/cage/day, fat consumption 4,58 to 8,51 g/cage/day, and energy consumption from 594,64 to 1154,50 kal/cage/day.
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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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