Judul: Analisis Nilai Tambah Serbuk Gergaji dan Internalisasi Eksternalitas Pengolahan Limbah Bag Log Jamur Tiram (Di Kelompok Tani Cijulang Asri, Kecamatan Cisarua, Kabupaten Bogor)
Abstrak: Oyster mushroom is a type of fungi that has a growth in demand because of its high nutrition. The increasing growth in demand makes oyster mushroom very potential to be cultivated. The increasing demand also causing the increase in oyster mushroom production as well as the usage of bag log as oyster’s growth media. Bag log is made from sawdust which is a waste. The increasing production also effect the waste which produced after the harvest of the oyster mushroom. The waste in form of used bag log need to be recycled so it can be reused and not polluting the environment. The characteristic of oyster mushroom home industry dan the compost making from bag log waste are categorized as small time industry with few workers and low in capital. The marketing of oyster mushrooms is by the help of a middleman. Compost from bag log waste is shipped to the city and to the country. Shipping in the city by the help of agents. Shipping to the country by the help of the government especially the ministry of agriculture and forestry. The added value of sawdust recycled by home industry Cijulang Asri into bag log is Rp 283.94 for a kg sawdust. The external cost internalized by the making of compost from the bag log waste is Rp 70,485,014 each year.
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Judul: Kelayakan Usaha dan Nilai Tambah Olahan Jamur Tiram Putih (Pleurotus ostreatus) Di Bekasi
Abstrak: Bekasi is one of the area in West Java which has the lowest producing mushroom. The weather and the temperatures factor in Bekasi did not support the mushroom production. Nevertheles, it did not discourage the mushroom preneur to passion the oyster mushroom cultivation in Bekasi. One of them is CV. Megah Makmur Sentosa. Therefore, CV. Megah Makmur Sentosa has a plan to develop the oyster mushroom bussines through build a newlarge capasity kumbung to maximazing production capacity in a area in Bekasi. Feasibility study needs to analize a oyster mushroom bussiness. The main aspects in feasibility are non-financial aspect and financial aspect. Non-financial aspect are market, technical, management, legal, social, economy and enviromental. It’s also analyze many changes around bussiness using switching value. Switching value was used to analyze maximum changes in cost and benefit. More over, value added was another analysis tool that calculated the oyster mushroom product. The results will show feasible of investment to implement the oyster mushroom business. The results of the financial analysis showed, the NPV value is Rp 170.590.527, IRR value is 59,60 percent, Net B/C value is 2,50 and discounted payback periodfor 4,44 years. While the analysis of the sensitivity with using switching value method obtained the maximum limit of output reduction is 15,85 percent, maximum limit of oyster mushrooms price reduction is 18, 28 percent, and the increase ofgas LPG cost is 589, 66 percent. Results of analysis showed that business of white oyster mushrooms are sensitive in changes of output and price of white oyster mushroom but is not sensitive in changes of LPG gas cost. Value-added analysis on these two products of process white oyster mushroom as nugget and crispy mushroom showed that the value addedof nugget is Rp 54.295 per kilogram while value added of crispy mushroom is Rp 25.545 per kilogram. This was showed that nugget product has a value added larger than crispy mushroom products.
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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