Judul: Use of space in the sexual behavior of timor deer (Cervus timorensis) in deer captive breeding of the IPB Darmaga
Abstrak: Pengembangbiakan rusa timor banyak mengalami kendala diakibatkan masih kurangnya pengetahuan mengenai faktor pendukung dalam keberlangsungan pengembangbiakan. Keberlangsungan pengembangbiakan rusa timor berkaitan erat dengan perilaku seksual rusa timor jantan terhadap rusa timor betina. Penangkaran rusa kampus IPB Darmaga merupakan salah satu contoh usaha pengembangbiakan rusa timor. Penelitian ini bertujuan mengidentifikasi perilaku seksual rusa timor dan penggunaan ruang dalam perilaku seksual rusa timor di penangkaran rusa kampus IPB Darmaga. Pengumpulan data dilakukan pada bulan Agustus-September 2020 melalui telaah pustaka, observasi lapang, dan wawancara. Analisis data dilakukan secara deskritif dan kuantitatif. Perilaku seksual rusa timor di penangkaran rusa kampus IPB Darmaga terdiri dari perilaku rusa jantan mendekati rusa betina, rusa jantan mencium alat kelamin rusa betina, rusa jantan mengendus urin rusa betina dan rusa jantan menaiki punggung rusa betina. Perilaku kopulasi tidak ditemukan selama pengamatan. Penggunaan ruang terhadap perilaku seksual rusa paling dominan merupakan tempat rusa menghabiskan waktu dan tempat pemberian pakan.
Keyword: IPB Darmaga, penangkaran, perilaku seksual, rusa timor

Judul: Perencanaan Penangkaran Rusa Timor (Cervus timorensis de Blainville) dengan Sistem Farming : Studi Kasus di Penangkaran Rusa Kampus IPB Darmaga
Abstrak: Timor deer (Cervus timorensis de Blainville) is one of Indonesia wildlife species which population growth on natural habitat facing many threats as impact of human activities, like wild hunting and habitat destinction and fragmentation. Timor deer can be developed as livestock in the future its ability in difference geographic area of Indonesia. Farming system is appropriate model to be developed, because majority of Indonesian farmers ha ve about less than 1 hectares of farm area. The objectives of this research are: to analyse suitable location, to analyse breeding plan and economical aspect. The research was caried out in captive breeding field labratory of IPB Darmaga Campus. Equipments which have been used are: digital camera, rool meter, weighing-machine and a set of computer with design program. Materials which used are: map, timor deers and plastic bags. This research used field observation method, literature study and interview method. Pursuant to this research with based on bioecological condition, IPB captive breeding is suitable for timor deer captive location. Farm location was devideed into: headquarter zone 0,10 hectare (2,35%) and captive breeding zone 4,15 hectare (97,65%). Captive breeding management to be executed is farming system. Based on economic analysis, until 21,35% interest, captive breeding with farming system still give advantage if population size of parent stock in first year are 105, and 210 in second year and to be taken care until ninth year, with payback period 4,53 years.
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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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