Judul: Perilaku Sosial Macaca tonkeana di Pusat Primata Schmutzer (PPS) Taman Margasatwa Ragunan, Jakarta
Abstrak: Macaca tonkeana or boti is black monkeys inhabit in the central part of the island of Sulawesi, Indonesia, in the districts of Uru, Palopo, Tonkean, Labua Sore, and Parigi. Macaca tonkeana are social animals living in groups. In a group, each individual will interact with others. Social interaction between individuals include grooming, agonistic, playing, and sexual behaviors. Behavioral observation was conducted starting at 08:00 am to 03:30 pm. Ad Libitum sampling and Focal animal sampling were used for daily behavior and social behavior observation respectively. Daily behavior most frequently performed was locomotion and feeding. Agonistic behavior was mostly done by adult females toward people with the percentage 69,2%. Grooming behavior was mostly carried out by adult female toward juvenile female with the percentage 88,9%. On sexual behavior, females are not only accepted but also refused copulation by a percentage 37,5%. Playing behavior was mostly made by juvenile in the form of biting, rolling and wrestling. In the game also found sexual learning.
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Judul: Perilaku seksual monyet ekor panjang (Macaca fascicularis) di Bumi Perkemahan Pramuka Cibubur, Jakarta
Abstrak: Sexual behavior is one of interaction between adult or subadult male and female that has significant role in maintaining group existency. Long-tailed macaques live in multi male multi fe~nale group, polygamous, and has no breeding season. Sosial behavior influenced by sosial hierarchy. Sexual behavior consists of mounting, intromission, thrusting, ejaculation, and dismounting. The objective of this study was to assess sexual behavior of long-tailed macaque (M. fasciszrlaris) in Bumi Perkemahan Pramuka Cihubur, Jakarta. The observation was carried out using ad libitum sampling and focal animal sampling. Daily activities were observed between 06.00 a.m. and 06.00 p.m. for 80 days (329 hour 17 minutes). Sexual activity occured in 2.33 % of total daily activity, and slowed higher frequency in the morning (06.00-10.00 a.m.) than other period of time: afternoon (10.00 a.m.-02.00 p.m.) and evening (02.00-06.00 p.m.). Sexual activity was identified has higher frequency on the ground than other places. The average duration of copulatory was 4.19 second. The high rank male did a lot of copulation, and genital inspect. Mostly, copulation occured without genital inspect. Male and female monkeys are more likely to take a rest after copulation.
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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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