Judul: Biogas as Fermentation Product of Baggase Hydrolysate Using Consortium Thermopilic Bacteria of Manure.
Abstrak: Growth of society and development of technology cause the world especially Indonesia require energy very much. Over exploitation of energy from unrenewable resource cause environmental damage and crisis of energy in the world. The purpose of this research was to produce biogas using baggase as substrate by thermophilic bacteria consortium of manure with fermentation. This research was begun by seed sludge preparation with heating 102 °C. A number of 75 ml of medium were mixed by substrate of glucose and baggase hydrolysate with different glucose concentration, that is 0.5, 1.5, and 2.5 g/L then were shaked for five days in normal temperature. The product of biogas was analyzed by gas chromatography with temperature of injector, detector, and column were 150, 250, dan 80 ºC. The result of this research shows the growing of bacteria was in accordance with decreasing of sugar concentration implying that the bacteria consume sugar to produce biogas. A mount of biogas produced in glucose fermentation 0.5 g/L, 1.5 g/L, and 2.5 g/L were 2.5, 13, and 38 ml respectively in the other hand baggase fermentation 0.5 g/L, 1.5 g/L, and 2.5 g/L were 0, 13, and 2 ml respectively. glucose fermentation produced hydrogen 0,6 % in the other hand baggase fermentation 0,9 %. So that baggase can produce biogas as alternative energy resource by using thermophilic bacteria of manure.
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Judul: Pembuatan Biogas Dari Sampah Buah-Buahan Melalui Fermentasi Aerobik Dan Anaerobik
Abstrak: Solid wastes and energy crisis are created by high growing rate of people. An alternative solving for both problems is biogas technology. Municipal waste can be proceed into biogas and fertilizer by biogas technology. In general, the process of conventional biogas technology has long time about 40 days (in tropical countries) and 100 days (in subtropical countries). The main goal of the research was to shorten the retention time of biogas production by combining its aerobic and anaerobic processes with optimized environmental condition (temperature) and substrate composition (C:N ratio) in anaerobic phase. Hydrolysis and acidogenesis were set in aerobic phase, while asetogenesis was set in anaerobic phase. Fruits waste were set into pre-treatment, minimized waste size between 1-2 cm2 and water addition (1: 1). The mixed ingredients was added by E~ microorganism culture and took into digester to start aerobic process. After 5 days, the process was stopped then substrate took to anaerobic digester to produced biogas (methano~enesis). Anaerobic process was set at different temperatures (30,35 and 40 C) and C:N ratios (20,25 and 30). The beginning of water content and C:N ratio of substrate were 86,24 % and 70,32: 1. Respectively, in aerobic process substrate was degraded by microorganism into simple compound. This process can be analyzed by C:N ratio change of total solid (TS), total volatile solid (TVS), chemical oxygen demand (COD), volatile fatty acid (VF A) and acidity degree (pH). Methanogenesis (anaerobic process) was monitored by the volume of biogas produced and analyzed COD, VF A and pH. The optimum of production rate and volume ofbiogas produced was achieved by treatment in 35°C temperature and 30: 1 C:N ratio, which biogas has produced 26,5 ml in the ftrst day and 42,5 ml biogas in the end of biogas production with the highest production rate was 9,6 mVday. It showed that activity of methanogenic microbe was optimum in that treatment condition.
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Judul: Pricing of Lookback Options with Floating Strike Price Using The Monte Carlo Method
Abstrak: Opsi lookback adalah opsi yang payoff-nya bergantung pada harga saham terbesar atau harga saham terkecil yang dicapai selama masa berlaku opsi. Opsi lookback dikatakan dengan floating strike price jika nilai dari strike price sebesar harga saham pada saat jatuh tempo. Nilai hampiran opsi lookback ditentukan dengan metode Monte Carlo, sedangkan nilai eksak didapat dari nilai simulasi terbesar yang mampu dihitung oleh komputer. Berdasarkan hasil penghitungan, nilai galat relatif yang dihasilkan semakin kecil dengan semakin bertambah banyaknya simulasi yang dilakukan, sehingga metode Monte Carlo untuk menghitung harga opsi lookback dengan floating strike price konvergen ke nilai eksaknya., Lookback option is an option whose payoff depends on the maximum or minimum of the asset price reached during the option period. The lookback option is said to be a floating strike price if the value of the strike price is equal to the stock price at maturity. The value of the lookback option is determined by the Monte Carlo method, while the exact value is obtained from the largest simulation value that the computer can compute. Based on the calculation results, the resulting relative error value get smaller with the increasing number of simulations performed. Therefore, the Monte Carlo method to calculate the price of the lookback option with the floating strike price converges to the exact value.
Keyword: lookback option, floating strike price, Monte Carlo method, convergent