Judul: Evaluasi Kualitas Fisik Tepung Inti Sawit dengan Bahan Pengisi Onggok dan Gaplek selama Penyimpanan
Abstrak: Tingginya harga bahan pakan impor menyebabkan harga ransum menjadi tinggi, sehingga perlu dilakukan peningkatan efisiensi penggunaan bahan pakan lokal untuk mengurangi ketergantungan terhadap bahan pakan impor. Meningkatnya kebutuhan ternak terhadap pakan mendorong terciptanya bahan pakan yang berkualitas. Kualitas bahan pakan dapat diuji dengan menggunakan beberapa metode salah satunya adalah uji fisik. Tujuan penelitian ini adalah untuk mengukur perubahan sifat fisik tepung inti sawit selama penyimpanan dengan bahan pengisi onggok dan gaplek. Taraf perlakuan yang diberikan adalah P1 (100% inti sawit), P2 (15% onggok + 85% inti sawit), P3 (30% onggok + 70% inti sawit), P4 (45% onggok + 55% inti sawit), P5 (15% gaplek + 85% inti sawit), P6 (30% gaplek + 70% inti sawit), dan P7 (45% gaplek + 55% inti sawit). Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) pola Faktorial (7x3) dengan 3 ulangan. Faktor pertama adalah jenis bahan perlakuan (P1, P2, P3, P4, P5, P6, dan P7) dan faktor kedua adalah lamanya penyimpanan (0, 4, dan 8 minggu). Peubah yang diamati adalah perubahan berat jenis (kg/m3), kerapatan tumpukan (kg/m3), kerapatan pemadatan tumpukan (kg/m3), sudut tumpukan (°), ukuran partikel (mm), dan pH bahan. Jika terdapat hasil yang berbeda nyata diuji lanjut dengan menggunakan uji kontras ortogonal.
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Judul: Evaluasi Kualitas Fisik dan Bilangan Asam Pakan Mengandung Tepung Inti Sawit yang Ditambah Pollard atau Dedak selama Penyimpanan
Abstrak: High production in palm kernel oil industry may open opportunities in the utilization of palm kernel into feed ingredients. The study was aimed to determine physical properties and acid value of diets containing palm kernel powder in room temperature. The analysis of experiment which have been used is CRD Factorial (2 x 3) with factor A were (feed containing palm kernel powder + pollard) and R2 (feed containing palm kernel + rice bran), factor B was storage time (0, 3, 6 weeks) with three repetition. The physical properties evaluated were density, bulk density, compacted bulk density, angle of respose, particle size, pellet durability, treshold energy, organoleptic, and water content. The results showed that R1 had a higher compacted bulk density than R2. The diet treatments did not significantly affect the density, bulk density, angle of respose, particle size, and treshold energy. An increase of acid value and decrease of pellet durability was occurred at the 3rd week of storage. In concluded that both of diets could not be stored for more than three weeks at room temperature.
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Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model