• Title/Summary/Keyword: Cool Water

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Performance Evaluation of Open-Loop Ground Water Heat Pump system (개방형 지열히트펌프 시스템의 성능평가)

  • Kim, Tae-Won
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.11a
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    • pp.9-14
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    • 2006
  • Open loop or ground water heat pump systems are the oldest of ground-source systems. Standing column wells can be used as highly efficient ground heat exchanger in geo-thermal heat pump systems, where hydrological and geological conditions are suitable. These systems require some careful considerations for well design, ground water flow, heat exchanger selection etc This paper describes 9round water temperature variations, performances in heat ins and cool ing mode and the results of ground water analysis.

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Conceptual Development of a Subminiature Cool Pad Applying Sorption Cooling Effect (흡습 냉각 원리를 이용한 소형 냉각 패드에 관한 연구)

  • 황용신;이대영;김우승
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.2
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    • pp.121-127
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    • 2004
  • This paper describes conceptual development and idea-verification of a sub-miniature portable cooler which dose not necessitate any pre-cooling nor any external energy supply. The basic principle of the cooling mechanism is the vaporization of water and sub-sequent cooling due to the evaporative latent heat loss. In this work, the vaporization of the water is stimulated by desiccant material to improve the cooling effect. The evaporative cooling caused by the desiccant is modeled and analyzed considering the sorption characteristics of the desiccant. In addition, the portable cooler is fabricated in the shape of a thin pad, and its cooling characteristics are tested and compared with the analytic results.

Application of District Cooling System for Deep Ocean Water by Case Study (사례 분석을 통한 해양심층수의 지역냉방시스템 적용 방안)

  • Jin, Su-Hwuy;Park, Jin-Young;Kim, Sam-Uel;Kim, Hyeon-Ju
    • 한국태양에너지학회:학술대회논문집
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    • 2011.04a
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    • pp.179-184
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    • 2011
  • The development of new energy has attracted consideration attention due to the high oil price and environmental problems. In advanced country, they have tried to carry out a long range plan for energy. We need to develop new energy for Low Carbon Green Growth in Korea. The building is 30% among ratio of energy consumption in Korea. And in the past, heating energy was high ratio for energy using at home. But recently, the demand for cooling energy keeps growing due to rising average temperature on the earth and improvement of life quality. In this situation, the energy of lake water and ocean water has studied to utilize in advanced country because of low temperature at underwater. But the study for deep water is still a lot left to do. In this study, we analyzed district cooling system and the present condition. Analyzing the deep lake water cooling system in Toronto, we found an application of district cooling system using deep ocean water. Deep lake water uses heat source for district cooling and water source for city in Toronto. So reducing the initial cost, this city had economic effect. When DLWC was applied at existing building, the heat exchanger was installed instead of cooling tower and refrigerator. And the heat exchanger used to connect main pipe with cool water on city. System using deep ocean water can be applied as a similar way to supply cool water from lake to building.

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Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 2: Characteristics of Fog Water Chemistry and Fog Deposition in Northern Japan

  • Yamaguchi, Takashi;Noguchi, Izumi;Watanabe, Yoko;Katata, Genki;Sato, Haruna;Hara, Hiroshi
    • Asian Journal of Atmospheric Environment
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    • v.7 no.1
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    • pp.8-16
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    • 2013
  • The fog water chemistry and deposition in northern Japan were investigated by fog water and throughfall measurements in 2010. Fog water was sampled weekly by an active-string fog sampler at Lake Mashu from May to November. Throughfall measurements were conducted using rain gauges under three deciduous trees along the somma of the lake from August to October. The mean fog deposition rate (flux) was calculated using throughfall data to estimate the total fog water deposition amount for the entire sampling period. $NH_4{^+}$ and $SO{_4}^{2-}$ were the most abundant cation and anion, respectively, in the fog water samples. A mean pH of 5.08 in the fog water, which is higher than those in rural areas in Japan, was observed. The [$NH_4{^+}$]/[$SO{_4}^{2-}$] equivalent ratio in fog water was larger than 1.0 throughout the study period, indicating that $NH_3$ gas was the primary neutralizing agent for fog water acidity. The mean rate and total amount of fog water deposition were estimated as 0.15 mm $h^{-1}$ and 164 mm, respectively. The amounts of nitrogen and sulfate deposition via fog water deposition were corresponded to those reported values of the annual deposition amounts via rainfall.

An Experimental Study on Heat Transfer Characteristics in the LHSS for Cool Thermal Air Conditioning (저온공조용 잠열 축열조의 열전달 특성에 관한 실험적 연구)

  • Seo, I.H.;Koh, J.Y.;Lee, C.M.;Yim, C.S.
    • Solar Energy
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    • v.20 no.3
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    • pp.11-19
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    • 2000
  • In this study, the basic data which were required for development of LHSS(latent heat storage system) were experimentally obtained. Experiments were carried out under the following conditions. The initial temperatures of P.C.M. which were used by parameter is $5^{\circ}C,\;9^{\circ}C$ and $14^{\circ}C$. The conditions of working fluid are $-6^{\circ}C,\;-4^{\circ}C$, and $65{\ell}$/min.. The pure water of which the freezing point is $0^{\circ}C$ was filled in the system, and the Ethylene glycol(brine) was circulated through the 10 vertical tubes as a secondary fluid in order to cool the P.C.M. down. The inlet temperature of the secondary fluid and the initial temperature of the water were varied to investigate the effects of the important design parameters. The phenomenons of temperature conversion of P.C.M. were appeared for the conductive heat transfer and free convective heat transfer by buoyancy force in this storage unit system. In order to find the effective water circulation path, we obtained P.CM. temperature distributions of 5 parts in the storage tank during freezing process.

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A Hydrological Analysis of Current Status of Turbid Water in Soyang River and Its Mitigation (소양강 탁수 현황과 저감에 대한 수리학적 분석)

  • Lee, Jin-Yong
    • Journal of Soil and Groundwater Environment
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    • v.13 no.6
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    • pp.85-92
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    • 2008
  • Water in Soyang River is an essential source for citizens of Chuncheon and Seoul areas. In 2006, turbid water in Soyang River aggravated by the typhoon Ewiniar, sustained for over 280 days unlike conventional years, then which interrupted water supply of Chuncheon and Seoul areas. Soil erosion derived from high cool lands constituting about 55% of Soyang River area is considered one of main causes for the turbid water, including imprudent development of mountainous area, road expansion, and road construction for forestry. According to analysis of turbidity, precipitation and reservoir level in Soyang River region for June 2006${\sim}$August 2008, the turbidity showed a peak correlation (r = 0.28) at a lag time of 49 days and especially did an excellent correlation (r = 0.60) with the reservoir level at a lag of 4 days. In the meantime, a critical turbidity of 31 NTU at Soyanggang Dam was estimated, over which would cause turbid water at Paldang Dam. In addition, a master recession curve was suggested, from which sustaining time of turbid water can be predicted.

A Computational Analysis of Water-Hammer (수격현상에 대한 수치적 고찰)

  • Chun, Kwang-Min
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.11 no.1
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    • pp.1-10
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    • 1982
  • The water-hammer phenomena caused by pump power failure are analysed by digital computer. Asan cool ins water pipe system has been chosen as a model. It is Shown that after power failure the pressure at the pump outlet drops sharply, and to prevent reverse flow, either butterfly valve or check valve can be used. After the valve closure, pressure oscillates behind the valve. To weaken the pressure wave, it is recommended to install a servo-operated valve in a bypass Line around the pamp and the check valve.

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Comparison of Clinical Outcomes Using Various First-Aid Cooling Method for Burn (다양한 화상 응급처치의 치료효과 비교)

  • Lee, Jung Hwan;Song, Woo Jin;Kwon, Min Ju;Park, Yang Seo;Ko, Jang Hyu
    • Journal of the Korean Burn Society
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    • v.24 no.1
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    • pp.7-13
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    • 2021
  • Purpose: Currently, the most recommended method for burn first aid is the cool running water for 20 minutes (CRW20). If CRW20 is not practicable, cooling dressing products with tea tree oil are used as substitutes. In this study, we analyze the effect of various burn first aids, including CRW20, cooling products, on the treatment period. Methods: This study was conducted on patients who suffered burns and visited Hangangsoo Hospital from March 2019 to March 2020. The study conducted in a retrospective method. The duration of treatment was analyzed by dividing the experimental group. Results: The treatment period was shortened when first aid was given (P<0.001). Cold water, ice, and ice packs resulted in reduced treatment periods (P<0.001, P=0.004). The treatment period was reduced when cooling dressing products were used in all groups (P=0.041). The implementation of first aid has reduced the duration of burn treatment. This means that cooling helps burn treatment. CRW20 did not show statistically meaningful results. This is the result of a failure to fully control the temperature and time of tap water. In addition, the change in temperature of tap water according to season, the use of water is higher than that of animal testing, and the general lack of information on proper burn first aid may have affected. Conclusion: The treatment period was statistically significantly reduced in the group that performed first aid. Among the various first aid methods, cold water and ice reduced the treatment period.

Effects of Capillary Water Interruption Layer on the Growth of Zoysiagrasses and Cool-season Turfgrasses in Reclaimed Land (염해지에서 모세관수 차단층 설치 유무에 따른 한국잔디 및 한지형 잔디류의 생육)

  • Kim, Jun-Beom;Yang, Geun-Mo;Choi, Joon-Soo
    • Asian Journal of Turfgrass Science
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    • v.23 no.1
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    • pp.35-44
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    • 2009
  • This study was carried out to examine the growth performance of 4 species of cool-season grasses and 4 species of zoysiagrasses under salt injury in Seo-san reclaimed area. Grasses were grown on the plots with capillary water interruption layer (WCWIL) and without capillary water interruption layer (WOCWIL) soil systems. Cool-season grass and seeding-type zoysiagrass plots were seeded on 6 Jun, 2006. Vegetative zoysiagrass 'Junggi' was established by sprigging and 'Senock' and 'Millock' were plugged. Electric conductivities of irrigation water (ECw) ranged from 0.28 to $3.3\;dS{\cdot}m^{-1}$. Electric conductivities (ECe) of the soil with capillary water interruption layer and without capillary water interruption layer ranged from 0.55 to $9.4\;dS{\cdot}m^{-1}$ and from 1.84 to $9.4\;dS{\cdot}m^{-1}$ respectively. Leaf color, turf quality, coverage rates, and growth rates were rated visually for 2 years. Zoysiagrass 'Junggi', creeping bentgrass, zoysiagrass 'Senock' and 'Millock' showed acceptable growth at salty fairway condition, while Kentucky bluegrass, perennial ryegrass, Kentucky bluegrass mixed with perennial ryegrass, and seeded zoysiagrass 'Zenith' showed establishment rates below 70%. These results will be useful when choosing turf grass species and cultivars for the golf courses in reclaimed land area.