Judul: Pengaruh Pupuk FMP dan OST terhadap Pertumbuhan dan Produksi Tanaman Semangka (Citrullus vulgaris Schard.)
Abstrak: Latar belakang penelitian yaitu FMP (Fused Magnesium Phosphate) dan OST (Organic Soil Treatment) merupakan pupuk dan bahan organik baru yang belum umum digunakan oleh petani. Pupuk FMP mengandung 20% P2O5 dan 15% MgO. Menurut brosur OST dari penyalurnya, bahan organik tersebut lebih baik dibandingkan pupuk kandang karena mempercepat pelepasan mineral tanah dan penggunaannya lebih sedikit.
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Judul: Pengaruh Taraf Pupuk Organik Yang Diperkaya Terhadap Pertumbuhan Jagung Manis (Zea Mays Saccharata Sturt) Dan Sifat Kimia Tanah Pada Latosol Di Darmaga
Abstrak: The negative impact caused by the use of inorganic fertilizers pushes fanner to return to organic fanning system. However, because the decomposition process of organic fertilizers is slow and its amount is limited, the nutrition which can be absorbed by crop for its h'fO,,,,th is a little. Therefore, it is needed to combine organic fertilizers with inorganic fertilizers. The objective of this research was to evaluate the effectiveness at 6 levels of enriched organic fertilizer levels on the yield and the chemical of soil properties. This research was carried out in the experimental field of Cikabayan, Bogor. The plant analysis was done in the Laboratory of Chemistry and Soil Fertility, Soil Sciences Department, Faculty of Agriculture, Bogor Agricultural University. The study was conducted from March until September 2003. The treatnients consisted of 6 levels of enriched organic fertilizers: PO (dosage: 0 ton/hal; PI (dosage: 10 ton/hal; P2 (dosage: 20 ton/hal; P3 (dosage: 30 ton/hal; P4 (dosage: 40 ton/hal; and P5 (dosage: 50 ton/hal, with 4 replications. So, there were 24 treatments unit in this research. These fertilizers were consisted of organic fertilizers - 60 % of compost and 25 % of cow dung - combined with these inorganic fertilizers - 7 % of dolomite, 2 % of urea, 4 % of SP-36, and 2 % ofKe! The result of this research indicated that the enriched organic fertilizers treatments have an effect to improvement of measured parameters value. The best of yield, high of plant, and the chemical of soil properties were obtained at treatment of P5 with dosage 50 tonlha of enriched organic fertilizers. The worst of yield, high of plant, and the chemical of soil properties were occurred at treatment of PO (without enriched organic fertilizers).
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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