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: Desain proses produksi biogas dari jerami padi dan sampah pasar dengan sistem fermentasi media padat
Abstrak: The purpose of this research were to design of fermentation process for converting rice straw and organic waste from traditional market to produce biogas, to know influence of aeration, to obtain the best feed addition in fermentation, and to obtain characteristic of product (digestate and leachate) from fermentation process. Beef cattle manure as substrate was inoculated to anaerobic digestion. Laboratory experiments using 10 l digester were performed in batch mode. The operating temperature was mesophilic condition (35-40oC). Fermentation rice straw with feed addition 75% new feeds and 25% digestate could produce 42.2 l gas/kg VS higher than fermentation rice straw from all new feeds (28.1 l gas/kg VS) and fermentation from 50% new feeds and 50% digestate (15.8 l gas/kg VS). While fermentation waste market from all new feeds could produce 51.8 l gas/kg VS higher than fermentation with feed addition 75% new feeds and 25% digestate (39.7 l gas/kg VS) and fermentation from 50% new feeds and 50% digestate (31.1 l gas/kg VS). The cumulative volume of biogas produced was used to measure the biodigester performance. The research gave the kinetic parameters of biogas production for rice straw i.e. biogas production rate constants (Rmax), maximum biogas production (A), and minimum time to produce biogas (λ) were 1.37-2.07 (l/kg VS.day), 15.82-42.25 (l/kgVS), and 0.4-2.0 days, respectively. While the organic waste from market gave the kinetic parameters U, A, and λ of 1.58-3.55 (l/kgVS.day), 31.09-51.84 (l/kgVS), and 0.2-1.2 days, respectively.
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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