Judul: Proses Co-Composting Abu Ketel dengan Bagas menggunakan Kotoran Sapi dengan Perlakuan Laju Aerasi dan Nilai C/N Awal
Abstrak: Boiler ash and bagasse contain high organic carbon and have a good characteristic, so it facilitate the circulation and air flow went into co-composting. The objective of this research were to utilize solid waste of sugar cane industry, in the form of boiler ash and bagasse by composting (co-composting) with addition of cow dung, to understand the influence of aeration rate to the compossing process of bagasse and boiler ash, as well as the cow dung, to understand the influence of first C/N to the compossing process of bagasse and boiler ash from sugarcane industry and also the cow dung. In this research, to increase nitrogen value, it was added with the cow dung. The cow dung contained high N, P, and K as compost. Co-composting was done by aerated pile method and a passive aerated treatment defines as a control. The treatment was done with different composition of bagasse, boiler ash, and cow dung and the different aeration. The aeration was conducted in the rate 0.8 l/minute kg ingredient, 1.2 1/minute kg ingredients, and C/N formulation 30, 40, 50. Composting process was done in 42 days with active aeration in the first week. The analysis showed that aeration technique had no significant effect to change the C/N value. Generally, aeration factor had no different interaction, while the first C/N formulation had different results.
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Judul: Pengomposan Blotong, Bagas dan Abu Ketel dari Industri Gula dengan Perlakuan Aerasi Aktif dan Perbedaan Nilai C/N Awal
Abstrak: Filter Cake, Bagasse and Boiler wastes in the sugarcane industry has not been used optimally. Therefore, it is necessary to studies use of composting. The purposes of study are to optimize the wastes utilization with composting and to know the influence of different active aerationrate and different initial C/N value on composting process and product. The research method using complete randomized design with two treatments, namely active aeration treatment with air drainage and passive aeration (without air drainage). The aeration active composting in the first week, then in the second week until the end of composting by air supply naturally. Composting consists of three composition based on initial C/N value, they are 30, 40 and 50. In term of active aeration rate, composting consists of two aeration rate, they are 0.8 l/kg.minute and 1.2 l/kg.minute. Parameters monitored during composting such as, temperature is done every day, pH and C/N is every week. Upon the completion of composting which is 42 days, compost is characterized to define the quality of compost and compare with SNI 19-7030-2004. The composting with aeration treatment of active and passive aeration does significantly affect the value of C/N and the different initial C/N value composition significantly affect the value of C/N by anova statistic. The compost, in physically, pH value and potassium content does meet the requirements of the compost, but it does not meet the requirements in water content, phosporus content and C/N Value, based on SNI 19-7030-2004.C/N value of the compost is 23.44 and water content is 54.56%
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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