Judul: Carob as Alternatif Energy Source Dairy Concentrates on Fermentability and Digestibility In Vitro
Abstrak: Tujuan penelitian ini untuk mengevaluasi penggunaan carob sebagai sumber energi alternatif menggantikan molases dan onggok terhadap fermentabilitas dan kecernaan konsentrat sapi perah. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) yang terdiri atas lima perlakuan yang terdiri dari konsentrat dengan onggok 10% (K1), konsentrat dengan molases 10% (K2), konsentrat dengan onggok 5% + carob 5% (K3), konsentrat dengan molases 5% + carob 5% (K4), serta konsentrat dengan carob 10% (K5) dengan empat kelompok berdasarkan pengambilan cairan rumen. Analisis data menggunakan metode ANOVA dengan SAS ODA dan jika berpengaruh nyata diuji lanjut Tukey. Hasil analisis menunjukan substitusi carob tidak berpengaruh nyata (P>0,05) terhadap pH rumen, populasi bakteri, populasi protozoa, kecernaan bahan kering dan bahan organik, namun berpengaruh nyata (P<0,05) terhadap konsentrasi NH3 dan VFA. Penggunaan carob sebagai kombinasi sumber energi sebanyak 10% dapat meningkatkan konsentrasi VFA yang dihasilkan serta mempertahankan pH, konsentrasi NH3, populasi mikroba, dan kecernaan., The objective of this study was to evaluate the use of carob as an alternative energy source replacing molasses and tapioca waste on the fermentability and digestibility of dairy cattle concentrate. This study used a Randomized Block Design (RDB) consist of five treatments including concentrate with 10% tapioca waste (K1), concentrate with 10% molasses (K2), concentrate with 5% tapioca waste + 5% carob (K3), concentrate with 5% molasses + 5% carob (K4), and concentrate with 10% carob (K5) with four groups based on rumen fluid sampling. Data analysis was performed using ANOVA method with SAS ODA and if significant effect, further tested with tukey. The results of the analysis showed that substitution of carob did not significantly affect (P>0.05) rumen pH, bacterial population, protozoal population, dry matter digestibility and organic matter digestibility, however, substitution significantly affected (P<0.05) NH3 concentration and VFA. The use of 10% carob as combination of energy sources can increase VFA produced also maintain pH, NH3, microbial population and digestibility.
Keyword: carob, Energi, molases, onggok

Judul: Utilization of Carob Powder with Different Levels in the Ration on Rumen Fermentability and In Vitro Digestibility of Heifers
Abstrak: Penelitian ini bertujuan mengevaluasi formulasi ransum sapi perah fase dara dengan penggunaan bubuk carob terhadap fermentabilitas dan kecernaan ransum in vitro. Penelitian menggunakan Rancangan Acak Kelompok dengan total 4 kelompok pengambilan cairan rumen dengan 4 perlakuan berdasarkan level penggunaan carob sebesar 0% (P1), 5% (P2), 7% (P3), dan 10% (P4). Parameter yang diuji meliputi pH, kadar NH3, kadar VFA total, populasi bakteri total, populasi protozoa, serta KcBK dan KcBO. Data dianalisis dengan metode ANOVA, apabila berbeda nyata diuji lanjut Duncan dan polinomial SPSS versi 25. Hasil penelitian menunjukkan penggunaan bubuk carob berpengaruh nyata terhadap kadar NH3, VFA total, KcBK, dan KcBO, sedangkan level penggunaan bubuk carob tidak berpengaruh nyata terhadap pH, populasi protozoa dan bakteri. Dapat disimpulkan bahwa penggunaan bubuk carob 5% pada ransum dara termasuk optimal, dapat ditoleransi, tidak mengganggu fermentabilitas serta menghasilkan kecernaan pada taraf normal.
Keyword: bubuk carob, fermentabilitas, in vitro, kecernaan, penggunaan, carob powder, fermentability, carob, utilization, caroube, ceratonia siliqua

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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