Judul: Daya Cerna Protein serta Kandungan Mineral (Kalsium dan Fosfor) pada Snack Bar Substitusi Tepung Pisang (Musa paradisiaca) dengan Tepung Pury Ulat Sutera (Bombyx mori) dan Tepung Lele (Clarias gariepinus).
Abstrak: Snack bar merupakan salah satu jenis makanan selingan yang dapat dibuat dari tepung pisang, tepung pury, dan tepung lele. Penggunaan berbagai tepung ini untuk meningkatkan kandungan gizi. Tujuan penelitian ini menganalisis daya cerna protein serta kandungan kalsium dan fosfor pada snack bar tepung pisang dengan substitusi tepung pupae-mulberry (pury) ulat sutera (Bombyx mori) dan tepung lele (Clarias gariepinus). Tahapan penelitian, yaitu analisis sifat kimia tepung pury, formulasi dan pembuatan snack bar, analisis daya cerna protein secara in vitro, analisisi kandungan kalsium dan fosfor, penentuan formula terpilih dan takaran saji snack bar, serta harga ekonomis snack bar. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap dengan perlakuan tingkat substitusi tepung pury sebesar 25%, 30%, dan 35%. Hasil uji statistik menunjukkan perlakuan berbagai perbandingan tepung pisang dan tepung pury tidak berpengaruh nyata terhadap daya cerna protein serta kandungan kalsium dan fosfor (p˃0.05). Formula terpilih berdasarkan pertimbangan hasil uji hedonik, daya cerna protein, dan kandungan kalsium serta fosfor adalah formula 3 (F3). Snack bar F3 memiliki daya cerna protein sebesar 97.44%, kandungan kalsium sebesar 257.66 mg/100 g, dan kandungan fosfor 312.99 mg/100 g. Snack bar formula terpilih per takaran saji (53 gram) memenuhi 10.8% protein, 11.13% kalsium dan 21.26% fosfor terhadapa AKG.
Keyword: Daya cerna, protein, kalsium, fosfor, tepung pury

Judul: Pemanfaatan tepung jewawut (Pennisetum glaucum) dan tepung ampas tahu dalam formulasi snack bar
Abstrak: Snack is food which is consumed between main meals. That is why the demand for snack foods is increasing. Many of these snack found nowadays in Indonesia are lacking of bioactive components such as antioxidant and dietary fiber. One of famous snack types nowadays is snack bar. Not so many commercial snack bars are found in Indonesia. Most of them are imported product and expensive in price. In this research, snack bar made of local ingredients which contained bioactive compounds and dietary fiber was trying to be made. The local ingredients were from millet flour and okara flour. Millet is one type of cereals. Its common name is Pearl Millet (Pennisetum glaucum). Okara flour is one of the wastes from tofu production. Millet is the source of antioxidant and okara flour is source of fiber. Both of these ingredient are not used by people to be food raw materials. The other ingredients in this research were hunkue flour, sugar, skim milk, nutmeg fruit, and water. The aim of this research was to get the best formulation of snack bar based on organoleptic, antioxidant, and fiber analysis. The variables that were differentiated among formulas were ratio of millet and okara flour (1:1, 1:2, and 2:1) and fat source. Fat sources of these bars were palm oil and avocado. Six formulas were obtained from these two variables. Based on hedonic rating test, formula with palm oil obtained the highest score and the difference between flour ratios was not significant. The higher the percentage of additional flour okara, the level of total dietary fiber in product would be higher. Formula 1:2 using avocado had the highest fiber content (17,21%). However, formula 2:1 using palm oil had the highest antioxidant capacity (4,98 mg vitamin C equivalent per 100 gram product). The antioxidant activity was higher if the proportion of millet flour were higher in product. Based on the results, formula with the ratio of millet and okara flour= 1:2 was the best formula. The antioxidant capacity of that formula was 3,76 mg vitamin C equivalent per 100 gram product and the total fiber was 13,13%. This product contained water (12,5%), ash (1,7%), protein (12,65%), fat (22,8%), carbohydrate (62,86%), iron (64 ppm), zinc (16 ppm), and calcium (2308 ppm). The color of formula M1:2 were L= 61,12, a= +5,89, b= +2,86, and 0Hue= 77,23. The hardness level of the chosen snack bar millet-okara formula was 852 gram force.
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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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