Judul: Improving putak nutritive quality using mixed culture Trichoderma reesei and Aspergillus niger as ruminant feed
Abstrak: Putak adalah nama pakan lokal di Pulau Timor Provinsi Nusa Tenggara Timur yang diperoleh dari isi (empulur) batang pohon gewang (Corypha elata robx). Kandungan pati dan serat kasar yang tinggi tetapi rendah protein merupakan kendala utama penggunaannya sebagai pakan. Proses pengolahan biologi melalui fermentasi dapat memberi hasil yang positif terhadap kualitas bahan. Kapang Trichoderma reesei dan Aspergillus niger secara kultur tunggal sering digunakan dalam pengolahan pakan karena kemampuannya dalam degradasi selulosa maupun pati menjadi protein.
Keyword: gewang tree (Corypha elata robx), goats diets, inoculum level, rumen fermentability, East Nusa Tenggara

Judul: Pola Fermentabilitas dan Kecernaan In Vitro Ransum Kambing Perah yang Mengandung Ampas Kurma
Abstrak: Date fruit waste (DFW) is a food industrial waste which was considered to be a nutritious feed, especially as an energy source. The use of DFW in the ration was not evaluated in the rumen fermentation and digestion. The general aim of this experiment was to evaluate the advantage of DFW in dairy goat ration by observing its pattern in the rumen in vitro, which consisted of study about the fermentability and digestibility of it and to investigate the effects of DFW on rumen microbial population. The results showed the addition of DFW increased dry matter digestibility and propionate proportion, and it had significantly change of ratio acetate:propionate compared than control. Furthermore, there were no effects to the concentration of N-NH3, proportion of butyrate and acetate, methane production, and organic matter digestibility. There was no effect of DFW on the population of total rumen bacteria and protozoa. As conclusion, addition of DFW can be allowed into dairy goat ration up to 50% of 40% concentrate when containing 30% Elephant grass and Indigofera sp.
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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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