• Journal of Advanced Marine Engineering and Technology
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• 제18권4호
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• pp.1-12
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• 1994

Most merchant ships are supplied with the only essential fresh water from a port for economical cargo transportation and the reduction of a nevigation expense. And the deficient fresh water for a voyage is produced by fresh water generator with the various exhaust energy generated in the engine room on a voyage. At present, an evaporation type fresh water generator are extensively used on ship because the operating cost of it is lower than that of a reverse osmosis pressure type. This study introduce a development results on the large evaporation type fresh water generator enable to be used for large merchant ships. It is accomplished the performance test using the developed large fresh water generator.

• 한국태양에너지학회 논문집
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• 제27권4호
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• pp.35-41
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• 2007

To demonstrate the desalination system, the demo-plant was scheduled to be installed. The system was planned to use solar thermal collector as heat source and PV as electricity source. For the design of the desalination demonstration system, firstly the solar thermal system would be well designed from the result between the supplied heat into the fresh water generator and the fresh water yield. The generator for demonstration system was chosen as the fresh water generator of the single stage and effect with plate-type heat exchanger using low pressure evaporation method. The test facility for the tests to reveal the relationship between the fresh water yield and the supplied heat flow rate was designed and manufactured. The maximum fresh water yield of two fresh water generators applied in this study was designed as 1.5 Ton/day. The parameters relating with the performance of fresh water generator are known as sea water inlet temperature, hot water inlet temperature, and hot water flow rate. Through the experiments, this study firstly showed detail operation characteristics of the generator and designed the solar thermal system for the demonstration system.

• Asian-Australasian Journal of Animal Sciences
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• 제1권3호
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• pp.163-166
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• 1988

Water turnover and consumption of steers fed either fresh cut grass or hay and water turnover of steers grazed in summer or in fall were determined using 18 Holstein steers weighing 226 to 382 kg. Steers consumed 7.0 or 7.5 kg of dry-matter from hay or fresh cut grass. Animals fed hay drank significantly more water than those given fresh cut grass (P<0.01). Total water consumption, however, was greater in steers fed fresh cut grass than those given hay (P<0.05). Water turnover was about the same as total water consumption with a tendency for slightly higher values in water turnover irrespective of feeding regimes. Steers grazed in summer had greater water turnover than those grazed in fall. Water turnover was about the same in steers fed fresh cut grass and grazed in summer but decreased in steers on the dry ration or grazing in a cool season of the year.

• 동력기계공학회지
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• 제15권2호
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• pp.25-30
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• 2011

A fresh water generation system is designed for converting brackish water or seawater into fresh water. In this paper fresh water generation by distillation process that evaporates feed water and subsequently condenses vapor as evaporation product to get fresh water was studied and city water was employed as feed water. The system uses the ejector to create a vacuum, under which liquid can be evaporated at lower temperature than it at normal or atmospheric condition, hence less energy consumption. The effect of various operating conditions i.e. temperature of feed water and different orifice diameters were studied experimentally to investigate the characteristic of the system. It was found that these parameters have significant effect in the performance of fresh water generation system with low pressure evaporation.

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.311-319
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• 1999

In Korea accelerated industry development and urbanization during the last three decades have led serious water pollution problems in many parts of the nation. Especially in the regions of west and south coast have low fresh water in the dry season of spring and summer. In the place isolated from land it is important to secure the fresh water for drinking and general service. This study is concerned on the thermal system design to develop low-pressure evaporation type fresh water gen-erator of capacity 1 ton/day using the heat source of non-operating boiler in the season of spring and summer. The results obtained from this study are as follows. the water quantitieds generated from experi-mental evaporator showed good coincidence with the calculated values. The maximum production quantity was 1.38ton/day at pressure 40mmHg abs. and temperature $80^{\circ}C$.

• 한국수자원학회논문집
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• 제48권1호
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• pp.23-35
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• 2015

본 연구에서는 3차원 수치모형을 이용하여 염수 대수층 내 담수 주입량에 따른 주입정과 양수정 사이의 담수체의 거동을 수치적으로 분석하였다. 대수층 내에 8개의 주입정이 동심원 상에 등간격으로 배열되어 있으며, 동심원 중심에 한 개의 양수정이 위치해 있다. 주입량이 상대적으로 작은 경우 주입정 주변의 담수체는 인근의 주입정에서의 담수체와 서로 혼합되지 않고 독립적으로 분포한다. 그러나 주입량이 증가함에 따라 담수체의 크기는 점차적으로 증가하며, 주입정과 주입정 사이에 염수와 담수가 혼합되어 있는 영역이 나타난다. 혼합되는 정도는 주입량이 증가함에 따라 증가되며, 이러한 현상은 양수정 주변에서도 동일하게 나타난다. 또한주입량이 증가할수록 양수정 주변 및 내에서의 염수비율이 점차적으로 감소하는 경향을 나타내었다.

• 한국식품영양과학회지
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• 제28권2호
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• pp.292-298
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• 1999

Myofibril and actomyosin were prepared from red muscle and white muscle of fresh water fish and sea water fish, and their biochemical characteristics and SDS PAGE patterns of myofibril were compared. SDS PAGE analysis showed that electrophoretic patterns of myofibril were similar be tween white muscle and red muscle, while difference of 30kDa component of myofibril was detected between fresh water fish and sea water fish. When myofibril were treated with trypsin, difference in hydrolysis of heavy chain was observed between white muscle and red muscle. In activities of Ca ATPase, Mg ATPase, EDTA ATPase and ATPase activity pH curve, myofibrillar protein from fresh water fish showed higher specific activity than those from sea water fish.

• Corrosion Science and Technology
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• 제10권6호
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• pp.218-224
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• 2011

The fresh water and sea water in present ships is used as cooling water for marine engine. Therefore, corrosion damage in seawater system is frequently occurred. In particular, in the impeller of pump, the performance and material span due to the corrosion and cavitation erosion has adverse effects. Most of the pump impellers in vessels are used Cu-Al alloy. Cu-Al alloy which having the excellent mechanical properties and corrosion resistance is widely used in marine environments. However, despite the excellent characteristics, the periodic replacement parts due to the cavitation damage in seawater is vulnerable to economic viewpoint. In this study, Cu-Al alloy used with impeller for centrifugal pump were conducted various experiments to evaluate its characteristics in seawater and fresh water solutions. As an electrochemical result, the dynamic conditions that exposed to the cavitation environment presented high corrosion current density with collapse of the cavity compared with the static conditions. Cavitation test results, the weightloss and weightloss rate in fresh water are observed more than those of seawater.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.727-733
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• 1999

In general ,wastes of livestock are covered 1% in the total wastes in Korea. But, actual pollutant loading rates by an organic material are 18% which will be serious problem in fresh water lake. An aim of this study is analyzing water quality in Bo-Ryeoung fresh water lake which are arounded by a lot of small livestock area, so that look for how to manage water quality of fresh waterlake.

• 한국태양에너지학회 논문집
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• 제27권4호
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• pp.27-33
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• 2007

In this research, to develop the practical application system of fresh water generation system with plate-type fresh water generator using low pressure evaporation method is the main object, and to do that, this study used the evacuated solar collector with operating range of about $50-85^{\circ}C$ as thermal energy source and solar photovoltaic as electric energy source. To achieve that object, this study set up the demo-plant, then estimated and analyzed the usefulness, the safety, and the reliability through pre-tests during short time ahead of the long-time operation. This study showed that the pumps, which are including sea water supply, ejector, hot water supply, and fresh water pumps, were operated one after another. And, the fresh water yield was closely related with the solar irradiance and lower supply temperature of hot water was revealed more reasonable for the solar energy desalination system. That is due to the insufficient area than the solar collector area being required that was estimated through the performance tests of the fresh water generator.