Judul: Perilaku Makan Gorila (Gorilla gorilla gorilla ) Di Pusat Primata Schmutzer Taman Margasatwa Ragunan Jakarta
Abstrak: Gorilla merupakan hewan diurnal teresterial. Makanan gorila berupa dedaunan dan buah, serta sedikit makanan berupa serangga. Penelitian ini bertujuan untuk mengidentifikasi perilaku harian dengan penekanan terhadap perilaku makan di dalam penangkaran Pusat Primata Schmutzer Jakarta. Pengamatan perilaku dengan metode focal animal sampling, dan ad libitum sampling. Hasil penelitian ini menunjukan bahwa persentase makan dan istirahat gorila lebih besar dibandingkan dengan perilaku lainya, yaitu 34,06% dan 29,32%. Hal ini dikarenakan gorila memiliki ukuran tubuh yang besar, sehinga waktunya lebih banyak dihabiskan untuk makan dan istirahat. Perilaku makan meningkat pada pukul 09.00, 12.00, dan 15.00. Persentase gorila mengambil pakan cenderung satu persatu 26,37%, pegang dengan satu tangan 17,69%, dan merobek dengan menggunakan gigi 24,19%. Posisi makan gorila lebih besar dengan duduk64, 36%, dan berbaring 27,10%.
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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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