• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.55-60
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• 2014

In general, A synchronous generator is higher than the voltage stability of the induction generator. However, induction generator has many advantages rather than a synchronous generator in terms of price and maintenance. So, coverage rate of the induction generator is gradually increasing in small hydroelectric power station rather than 1000kW recently. In order to increase the penetration of induction generator, pre-analysis of the operation of the generator is needed. In this study, we analyzed for the problems that occur when synchronous generator and induction generator of 1500kW is connected to the distribution system.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.16 no.2
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• pp.176-184
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• 1987

The purpose of this research is to study the characteristics of the coefficient of perform-ance (COP) of the small absorption refrigeration system. This experimental study is performed with two selected variables, the temperature of the generator and the input temperature of the cooling water. In order to determine the input temperature of the generator which gives maximum COP, the experimental data are obtained with controlling the temperature of the generator in the range of $20-32^{\circ}C$ of the temperature of the cooling water. The range of the generator heat suppling temperature which gives maximum efficiency is about $90-95^{\circ}C.$ The temperature range depends on the characteristics of the equipment unit. The most important result in this experiment is the trends of the COP in accordance with the variation of these temperatures. This trend will furnish the informations and knowledges for designing and operating the absorption refrigerator.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1997.06c
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• pp.141-149
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• 1997

Structural characteristic of a rice polisher of small size was analyzed to improve its performance and to utilize such data in developing a rice polisher of large size. Spraying characteristic of nozzles which were used for rice polishing was evaluated by a machine vision system. Internal pressure of the polishing chamber was also measured according to outlet resistance, water spraying, and roller shaft speed. In addition, the performance of the polisher was analyzed based on whiteness and broken ratio according to operating conditions.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.79-84
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• 2011

Air pollutants from a small marine diesel engine are increasing and the IMO(International Marine Organization) regulation asked for its reduction. In this study, NOx reduction technologies such as improvement of various cooling systems are applied to the small marine diesel engine. The various cooling systems are a intercooler, a heat exchanger for engine coolant, and an exhaust manifold by water cooling. These systems are tested on an engine dynamometer and a exhaust gas analyzer by a marine diesel engine test regulation. Test results are shows that the small marine engine are satisfied the IMO NOx regulations; Tire II.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.3
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• pp.305-314
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• 2014

A pilot plant (Q=5 $m^3/d$) study was implemented for small and medium sized personal wastewater treatment plant effluent to evaluate MBR and A/O processes utilizing self-sufficient energy composed of wind and solar energy. The removal efficiencies of BOD, SS, turbidity and color were sufficient for legal water quality standards for gray water. However, those of nitrogen and phosphorus could not meet legal regulations which suggested that further removal of those contaminants were needed for reuse of the treated water. Self-sufficient energy rate was 100 % for the pilot plant due to excessive design capacity. In this research, wind and solar energy system was applied considering geological characteristics, which significantly improved energy self-sufficiency. Substantial improvement on energy self-sufficiency can be obtained by optimized investment and operation at a full scale wastewater treatment plant.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.260-264
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• 2003

The application of solar energy, in the field of alternative energy, was on the increase tendency. In the case of advanced nations, through continuous R&D, solar-heat hot-water-boiler with high efficiency has been used for the house and the industrial process on business, advanced nations on reached up the experimental stage of solar generation system. But the actual circumstance of the domestic has been not accomplished the popularization of solar-heat hot-water-boiler and the settlement of it which is the fundamental stage of the solar energy usage. This trouble, the domestic was flooded with small enterprise for producing solar-heat hot-water-boiler, was caused by the popularization and the production without verification of performance. To supply the monitoring program for evaluating solar-heat hot-water-boiler, this research was purpose to improve the technical development of the enterprise for producing solar-heat hot-water-boiler and served as an aid f3r the enlargement and the popularization on solar energy.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.80-93
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• 1995

Membrane Technology, which has been in use for over twenty five years, has established itself as one of the principle separation methods. With improved technology, Reverse Osmosis ("RO") has been applied to large volume water treatment facilities. UF and MF Membrane Technology has, up until recently, been applied to small scale water treatment facilities. The fouling of membrane has restricted the growth of Membrane Technology in Water Treatment. Membrane fouling compound found in water causes the loss of flux across the membrane by absorbing to membrane and plugging their pores. Various methods have been used in the reduction and prevention of membrane fouling. For RO, a conventional pre-treatment system removes the pollutants, preventing the function decline of RO membrane by keeping SDI < 4 as the standard condition of feed water. UF and MF Membrane Technology that must have pre-treatment function within itself, are required to keep its ability not to be influenced by fouling.y fouling.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.312-320
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• 2015

The 1/5 scale-down model of the Bycatch Reduction Device (BRD) from an Argentinean demersal trawl was tested in a circulating water channel. The BRD is designed to help small Hake (merluza, merluccius hubbsi) to escape from a trawl. It is settled in front of a trawl codend, and is equipped with selection grids that help small fish to escape from the gear and guiding panels that help fish to meet with the grids. Bars of the grids are wires covered by the PVC and other parts of the BRD are made of net. When the velocity was less than 0.65 m/sec (2.81 Kont when translated to real towing speed) which is slow speed compared with real towing speed, position between an upper guiding panel and an upper selection grid were good to help small fish to escape. When the velocity was more than 0.8 m/sec (3.41 Knot when translated to real towing speed) which is similar to and faster than real towing speed, it was considered that small fish may have difficulties in escaping because the gap was not enough between an upper guiding panel and an upper selection grid. The lower selection grid was sat on the bottom of the tank without an angle due to the weight that it carries. Improvements were proposed to position the panels and the grids better.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.17-34
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• 1992

A novel drug delivery system, detergent-phospholipid mixed micelles as proliposomes, for water-insoluble compounds was developed by investigating (i) spontaneous formation of small unilamellar vesicles (SUV) from bile salt-egg phosphatidylcholine mixed micelles, (ii) the molecular mechanism of micelle-to-vesicle transition in aqueous mixtures of detergent-phospholipid, (iii) preparation and screening of a suitable liposomal formulation for a lipophilic drug: solubilization of the drug within the lipid bilayer, evaluation of the solubility limit, and characterization of the resulting product with respect to the physical properties and stability of the drug in the system, and (iv) testing antitumor activity in vitro. The results showed that the new carrier had a strong possibility to be a biocompatible universal formulation for water-insoluble drugs.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.604-609
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• 2005

Runoff characteristics of organic matters and nutrients from greenhouse site in paddy field area were investigated during the irrigation period in 2004. The greenhouse selected which situated near the Nam river, Jinju, Korea used the ground water as the irrigation purpose. And, the rotating system of paddy field to upland was adapted as a cropping system which is a typical practice in this area. Various items such as total phosphorus(T-P), total nitrogen(T-N), dissolved oxygen(DO), BOD, etc. were observed to figure out the seasonal and spatial variation in the study sites. it was found that the risk of water pollution due to the contamination of nutrients in canals in green house sites, and their neighbouring small sized streams are much higher than those in ordinary paddy field areas. Further surveys and investigations are required to find out the counter measures to reduce water pollution occurred in greenhouse sites.