Judul: Desain Konstruksi Jalan Usahatani di Petakan Tersier Lahan Sawah (Kasus di Cikarawang Bogor)
Abstrak: Hasil pertanian yang mempunyai sifat mudah rusak harus ditangani secara baik dan benar, sehingga penurunan mutu dan kehilangan hasil pertanian dapat dihindari. Oleh karena itu pada daerah sentra produksi pertanian diperlukan adanya prasarana jalan usahatani yang memadai. Tujuan penelitian ini adalah (1) mendesain konstruksi jalan usahatani di petakan tersier dan membuat prototipe subgrade jalan usahatani, (2) menguji kekuatan dari prototipe subgrade jalan usahatani. Kriteria desain konstruksi jalan usahatani di petakan tersier lahan sawah mencakup : (1) spesifikasi kendaraan / alat angkut yang direncanakan, (2) kriteria jalan usahatani, (3) kriteria saluran tersier, (4) karakteristik tanah dasar (subgrade) jalan usahatani. Pengujian dilakukan dengan Calfornia Bearing Ratio (CBR) rendaman untuk bahan tanah timbunan, dan dengan Dynamic Cone Penetrometer (DCP) untuk prototipe subgrade jalan usahatani. Nilai CBR akan berbeda-beda sesuai dengan kedalaman lapisan yang diuji. Pada kedalaman 0-340 mm, 340-590 mm dan kedalaman 590-950 mm berturut-turut diperoleh nilai CBR rata-rata sebesar 7.62%, 19.67% dan 21.90%, lebih besar dari nilai CBR rencana yaitu 5.7%. Hal ini berarti subgrade memenuhi syarat kekuatan. Hasil desain konstruksi jalan usahatani di petakan tersier adalah (1) lebar atas subgrade jalan usahatani 2 m termasuk perkerasan jalan, (2) tinggi subgrade jalan usahatani 0.90 m, (3) kemiringan subgrade jalan usahatani 1:1.2, (4) tebal perkerasan jalan usahatani 7 cm dan tidak dibuat prototipenya, (5) pada kedalaman tanah subgrade 0.50 m dipasang saluran tersier dari pipa berdiameter 6 inci.
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Judul: Desain Konstruksi Jalan Usahatani di Petakan Tersier Lahan Sawah (Kasus di Cikarawang Bogor)
Abstrak: Perishable nature of agricultural product must be handled properly, to avoid deterioration and loss of product. Therefore, the centre area of agricultural production requires adequate farm road. The objectives of this research were: (1) to design the construction of farm road at tertiary plot and make the subgrade prototype of farm road, and (2) to analyze the strength of subgrade prototype. The design criteria of farm road construction were identified based on : (1) specification of vehicle, (2) the criteria of farm road, (3) the criteria of tertiary canal, (4) the characteristics of subgrade. The strength of subgrade prototype was analyzed by California Bearing Ratio (CBR) and Dynamic Cone Penetrometer (DCP). The result showed that on the depth of 0 – 340 mm, 340 mm – 540 mm and a depth 590 mm – 950 mm consecutively CBR had an average value of 7.62%, 19.67% and 21.91%. These value were bigger than CBR plan 5.7 %. It indicated that the subgrade strength was eligible. Design result of farm road construction at tertiary plots of paddy field were: (1) width of subgrade of farm road 2 m, (2) height subgrade of farm road 0.90 m, (3) slope of subgrade farm road 1:1.2, (4) thickness of farm road pavement 7 cm and nor prototype, (5) the tertiary channel using 6 inch diameter pipe was installed at the depth of 0.5 m of subgrade soil.
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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