Judul: Kajian teknis dan eknomis pemakaian head-feed combing harvester (CA 385 EG) di daerah Sukamandi, Kabupaten Subang, Jawa Barat
Abstrak: Kemajuan sektor industri yang semakin pesat saat ini merupakan faktor yang mempengaruhi terjadinya pergeseran tenaga kerja dari sektor pertanian ke sektor industri. Pergeseran tenaga kerja ini memberikan konsekuensi bahwa efisiensi dan efektifitas dalam sistem usaha tani harus ditingkatkan, yaitu dengan menerapkan mekanisasi pertanian. Salah satu mesin pertanian adalah combine harvester. Penggunaannya akan mengurangi tenaga kerja dalam jumlah yang besar. Pemakaian combine harvester untuk pemanenan padi telah dilakukan di lahan sawah milik Perum Sang Hyang Seri di Sukamandi, Jawa Barat. Oleh sebab itu perlu dilakukan penelitian untuk menganalisa aspek-aspek teknis pemakaian, kapasitas kerja, susut panen dan aspek ekonomis yang mencakup biaya pemakaian alat. Penelitian ini bertujuan untuk melakukan kajian teknis dan ekonomis aktivitas pemanenan padi secara mekanis dan manual serta melakukan analisis kelayakan usaha pelayanan jasa pemanenan secara mekanis dengan menggunakan head-feed combine harvester tipe CA 385 EG. Pada pemanenan dengan combine harvester dilakukan pengamatan terhadap kondisi tanaman, kondisi lahan dan waktu yang digunakan untuk pemanenan. Untuk analisa biaya digunakan data sekunder berupa data bunga modal, umur ekonomis alat, biaya perbaikan dan pemeliharaan combine harvester, serta data primer antara lain data biaya operator, biaya bahan bakar dan performansi teknis. ...
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Judul: Studi Kapasitas Kerja dan Susut Pemanenan Rice Combine Harvester di Desa Sukamandi, Subang, Jawa Barat
Abstrak: Methode of paddy wet field harvesting could be done manually utilized sickle or mechanically utilized combine harvester. The objectives of the research was analyzing working capacity and harvesting losses of rice combine harvester A, rice combine harvester B, harvesting and thresher use sickle and power thresher and compare the result of analysis. Results of research showed that effective field capacity, and harvesting losses of rice combine harvester A were 0.486 ha/hour, and 2.013% respectively. Results of rice combine harvester B were 0.422 ha/hour, and 3.028% whereas effective field capacity of harvesting and threshing, yield capacity of threshing, and losses of harvesting and threshing were 0.006 ha/person.hour, 0.287 ha/jam, 1.550 ton/jam, and 17.087% respectively. Percentage level of cleanliness and intact unhulled rice use rice combine harvester A, rice combine harvester B, and power thresher were 98.3% and 97.6%, 98.3% and 97.3%, 97.7% dan 96.2% respectively, so that paddy wet field harvesting utilized rice combine harvester was more effective and efficient.
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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