Judul: Modifikasi dan Uji Fungsional Mesin Pemanen Udang Tipe Vakum
Abstrak: In Indonesia, the fishery commodities that can be developed are fish and shrimp. Fish and shrimp commodities is not only marketed in Indonesia but has been marketed overseas. So, the whole of the production process must be considered, one of them is harvesting that produced high-quality products. So far the harvesting process of fishery commoditiesin in Indonesia is still using the traditional method. The object of this research is to modify fish and shrimp harvester to produce an efficiency and effectiveness of harvesting machinery so that can be maintained the quality of fish and shrimp. Stages of this research are started from problems identification, analysis of the design, modification, and functional testing. Fish and shrimp harvester consist of vacuum pump and water pump. The functional aim of water pump is to suck commodities from the pond, where as and the vacuum pump is to maintain the vaccum condition inside the system. The results of this research obtained flow rate and suction velocity average are 1.84 l/s and 0.23 m/s in the tank 1. While in the tank 2, flow rate and suction velocity average are 1.63 l/s and 0.52 m/s respectively. At the end of this research, this modified fish and shrimp harvester is still not able to show good performance, and still need to conduct further research.
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Judul: Rancang Bangun Mesin Pemanen Udang Tipe Vakum
Abstrak: Shrimp is an important commodity for Indonesia, both in domestic and international markets. That quality is influenced by several factors including the harvesting process. So far, the harvesting process for fishery commodities in Indonesia is still using the traditional way. This research aims to design a vacuum-type shrimp harvester to improve the efficiency and effectiveness of farming productivity. So that the quality of shrimp harvested can be maintained high. Stages of this research starts from the problems identification, functional analysis, structural analysis, prototyping, and functional test. This design uses a vacuum system that is applied starting from the inlet channel, tanks, to the outlet channel. By using centrifugal water pump power, commodities in pond are inhaled and trapped in the tank without passing through the impeller. In addition, this design also uses a vacuum pump to maintain pressure in the system. It aims to solve the undetected leaks on the system. From the data obtained, the highest flow rate could reach 5.27 l/s with suction speed of 0.65 m/s, while the lowest flow rate is 4.75 l/s with suction speed of 0.59 m/s. Commodity that can be inhaled by this prototype is shrimp that has burst speed ranging in average of its suction speed, ie 0.61 m/s. It needs the next research to make the other harvesting mechanism to avoid the undetected leaks on the system
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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