Judul: Mempelajari Cara Pembuatan Biogas Melalui Proses "Rumen Derived Anaerobic Digestion" (Rudad)
Abstrak: Bahan-bahan organik alami seperti kotoran , limbah perkebunan, limbah pertanian, limbah industri dan bahan pertanian lainnya mengandung senyawa yang sukar atau tidak terde- - gradasi. Dalam biogas cara konvensional ha1 ini menjadi kendala yang belum terpecahkan sehingga efisiensi perombakan (degradability) terhadap bahan-bahan tersebut masih rendah. Cara yang dilakukan dalam penelitian ini adalah sistem pembuatan biogas melalui proses "Rumen Derived Anaerobic Digestion" atau disebut dengan proses "RUDAD". Kelebihan dari cara ini adalah penggunaan mikroba rumen ruminansia yang lebih beragam dibandingkan dengan mikroba yang terdapat dalam kotoran hewan. Mikroba yang terlibat dalam proses perombakan meliputi berbagai jenis bakteri, protozoa siliata (tak ditemukan secara alami di tempat lain) dan kapang fikomisetes.
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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: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite