Judul: Pengaruh Jenis Inokulum dan Waktu Inkubasi Terhadap Sifat Fisiko-Kimia Tempe Kacang Merah (Phaseolus vulgaris L.)
Abstrak: Tempeh is one of Indonesian’s favourite food and it is known as source of protein. Red bean or red kidney bean contains protein in high amount so that it has big potency to be utilized as raw material of tempeh. Mold mycellium that growth covering the beans will form the compact texture and also being the source of protein. This research uses factorial experiment design with two factors: inoculum type and incubation time. The production of red bean tempeh in this reasearch is using four types of inoculum which are Laru A (R.oligosporus), Laru B (R.oryzae), Laru C (R.oligosporus+R.oryzae 1:1), and Laru D (Laru A+Laru B 1:1) On the other hand, the incubation times used for this research are 24, 36, and 48 hours. Parameter which are measured to determine the optimum inoculum type and incubation time for red bean tempeh is protein content, especially soluble protein content. The other parameters are yield, the slicing force, and color. The red bean tempeh production steps are similar with soybean tempeh. Every type of inoculum and incubation time produced red bean tempeh with different physicochemical characteristics. Samples which have similar high protein content with 5% significancy are A48 (40.12%db), C48 (41.15%db), A36 (43.81%db), and B36 (46.05%db). Samples whose similar high soluble protein content are C36 (2.63%db), A36 (2.67%db), A48 (2.94%db), dan C48 (3.00%db) with 5% significancy. Samples with the highest yield are A36 (95.10%), D36 (95.15%), and C36 (97.21%), similiar with yield of 24 hours tempeh. The highest slicing force 198.1 N.mm (A48) while slicing force of soybean temoeh as control is 140.1 N.mm. Samples with similar brightness value with control (78.833%) are A24 (80.575%), A36 (76.740%), B48 (74.110%), and C36 (79.425%). The whole red bean tempeh samples show yellow as their dominant chromatic colour (a value = +0.230 to +6.150 and b value = +5.840 to +19.025).
Keyword: Bogor Agricultural University (IPB), R.oryzae, R.oligosporus, red bean tempeh, protein, incubation time

Judul: Pengaruh ketebalan dan persen aerasi terhadap karakteristik tempe grits kacang merah (Phaseolus vulgaris L.) ukuran 8 mesh
Abstrak: One of the commodities that can be used to make tempe is red beans (Phasolus vulgaris L.). Red beans are rich in carbohydrate complex and fiber, but the protein content is lower than soybean. Therefore, process engineering is required to increase protein content and yield of red beans tempe. The raw material used in this research is grits of red beans and starter (mixture of R. oligosporus and R. oryzae (1:1)). Two process parameters studied in this research are aeration area (1%, 2.5%, 4%) and thickness of tempe (1cm, 2cm, 3cm). The result showed that the force to slice tempe decreases as the thickness of tempe increases. The brigthness of red bean tempe is lower than soybean tempe and showing cromatic colors of red and yellow. The yield of red beans grits tempe ranges between 92.11%-96.79 %. Tempe with aeration treatment 4% and thickness 1 cm having the highest protein content (41.13 % db), soluble protein 23.31 g/100 g, and higest protein digestibility 91.26 %. Process engineering (size reduction and aeration level) applied in this research increases protein content and its digestibility because of the increased surface area which eventually maximize the gowth of fungi and hidrolize protein more effectively.
Keyword: yield, tempe, protein, red beans grits, Bogor Agricultural University (IPB)

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.
Keyword: