• 제목/요약/키워드: water temperature increase

검색결과 2,317건 처리시간 0.034초

원자력 발전소의 온배수를 이용한 해양온도차 발전의 타당성 검토 (OTEC System using the Condenser Effluent from Nuclear Power Plant a feasibility study)

  • 신상웅;천원기
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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    • pp.238.2-238.2
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    • 2010
  • Recently, environmental pollution and energy depletion problems have been issued over the world. For this reason, many renewable systems have been developing. Of these, the Ocean Thermal Energy Conservation(OTEC) is drawing attention as the upcoming alternative energy source. In this paper, the efficiency of each of OTEC which harness the effluent from nuclear power plant was analyzed by using computer calculation. The result, shows that Ul-jin Nuclear Power Plant is the best place geographically and the regenerative cycle is most outstanding performance cycle for OTEC. The difference of temperature between surface water and deep water temperature should be greater than $20^{\circ}C$ in order to increase the efficiency.

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다시마 열수 추출물의 한외 여과에 의한 분리 (Studies on the Separation of Hot Water Extract Seasoning Components from Sea Tangle by Using Ultrafiltration)

  • 강희호;이성갑
    • 기술사
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    • 제32권2호
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    • pp.99-109
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    • 1999
  • The dried sea tangle added for soup prepatation to improved the taste in Korean and Japaness for long time. Attempts were made to develop the best procedures for extraction and removal of alginate by ultrafiltration and diafiltration. The summerized results of this study are as follows: 1) For hot water extraction in temperature range of 60~100$^{\circ}C$ for 4 hours, the higher temperature resulted higher yields in solids and protein. 2) Optimum sea tangle hot water extraction condition were 60~65$^{\circ}C$ for 1 hour which was cheap operating cost and high yield of good taste components. 3) The membrane flux was more higher GR 51 PP. and increase of flow rate permeate flow rate was accordingly increased. but limiting flow volume was 3.7 l/min. 4) It was found that ultration was relatively of higher recovery rate, solid and taste components, and low rejection coefficient rate than diafiltration.

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한국 사람의 생리적 변화에 미치는 운동의 영향 (Effect of Exercise on the Physiological Changes of Korean Cyclists)

  • 김종국;이범진
    • Journal of Pharmaceutical Investigation
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    • 제25권2호
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    • pp.95-100
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    • 1995
  • Serum electrolyte concentration and body weight were determined before and after exercise for 2h in Korean cyclists. The serum concentration of electrolytes (Na, Ca, Zn, K, P and Cl) was increased but that of Mg was decreased as a result of exercise. The increase of serum K and P concentration was statistically significant after exercise. As the exercise time increased, the loss of body weight also increased due to dehydration and sweat. The loss of body weight ranged 1.0 to 2.3 Kg as a function of exercise time but cyclists showed the exhaustion and muscle fatigue 2h after exercise. As the ambient temperature increased, the loss of body weight was slightly increased. However, frequent drinking water was required because of dehydration and thirst. Although frequent drinking water may reduce weight loss and thirst during exercise, sports drinking beverages simultaneously containing electrolytes and nutrients are more useful to replenish loss of water and electrolytes in an exhausted condition, resulting in the improvement of physical performance.

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열처리에 따른 고려홍삼의 수용성 갈변물질의 특성 (Characteristics of the Water Soluble Browning Reaction of Korean Red Ginseng as Affected by Heating Treatment)

  • 이종원;이성계
    • Journal of Ginseng Research
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    • 제22권3호
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    • pp.193-199
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    • 1998
  • The purpose of this study was to Investigate characteristics of the water soluble browning reaction products (WS-BRPs) from Korean red ginseng by heat treatment. Absorbance of WS- BRPs was increased with increases of heating temperature and time, but pH value were decreased In Muter color value L and b value were decreased, while a value was increased. and absorbance at 280 nm in spectrum of the WS-BRPs was increased according to the increase of heating temperature. When the WS-BRPs were applied on Bio-Gel P-30 column after heating and pH treatment, two majors browning products increased according to the progress on time. And pH 3.0 increased in quantity of high molecular fractions and pH 8.0 increased in quantity of low molecular fractions.

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혼화제를 이용한 조강콘크리트 배합설계에 관한 연구 (A Study on the Mix Design of Early Strength Concrete using Admixture)

  • 박영신;남성우;박재명
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.69-72
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    • 2005
  • In this study, it is contents to application on AE water reducing admixture for high early strength, which reduce to construction period for cost down in construction. In experiment result on the kinds of AE water reducing admixture for concrete strength promotion, when passed 60 minutes, while it was happened on lignin and naphthalene system about $30\∼35\%$ that loss related to slump, slump flow and air, but happened about $8\∼10\%$ on polycarboxylic system. And the result of compressive strength tests, when 32 hours passed in polycarboxylic system than lignin and naphthalene system, was showing an increase of 10$\%$. Accordingly, concrete properties was measured to condition change by the addition amount and curing temperature of polycarboxylic system. The required curing temperature to gain 5MPa of compressive strength, which is capable of side form stripping, must keep more than smallest 12. 5$^{circ}C$ when polycarboxylic system is used. As a result, AE water reducing admixture of polycarboxylic system may apply effectively to high early strength concrete

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마늘의 저장온도에 따른 이화학적 품질변화 (Change of Physicochemical Quality According to Its Storage Temperature in Garlic (Allium sativum L.))

  • 장현세;홍경훈
    • 한국식품저장유통학회지
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    • 제5권2호
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    • pp.119-122
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    • 1998
  • This study was conducted to blow the effect of postharvest physiological changes on garlic quality according to its ecotypes and storage temperatures. The changes of water, total soluble solids, crude stein, md total fructans were measured and the rates of respiration and sprouting were analyzed during storage at 20$^{\circ}C$ and 30$^{\circ}C$. The decrease of water content and the increase of total soluble solids were reversely appeared during garlic storage. The crude protein content was gradually increased during storage but total fructan content was decrased. The respiration late was maximized at 60days after storage and the spouting rate was gradually increased. In the aspect of ecotypic characteristics, the water content, fructan content and sprouting rate were higher in 'Namdo' cultivar than those of southern type. The high storage temperature (30$^{\circ}C$) controlled spouting and loss of fructan, and it was effective to maintain the garlic quality.

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CFD모사를 이용한 저수지 물순환장치 유동 설계 (Design of convection current circulation system in reservoir using CFD simulation)

  • 이요상
    • 환경영향평가
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    • 제21권1호
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    • pp.133-142
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    • 2012
  • Convection Current Circulation System(CCCS) in stratified reservoir controls development of anaerobic condition and algal bloom during summer. In order to increase the CCCS effectiveness, we analyze diverse design parameters to make optimize the flow pattern in reservoir. In this study, we interpret the internal flow with installation and operation condition of CCCS based on CFD in reservoir. Design variables of CCCS is reservoir depth, stratification strength, distance of between CCCS and so on. Since reservoir depth and stratification strength in variables is depending on natural phenomenon, we evaluated current circulation effect by distance of CCCS and proposed the optimal design condition using CFD simulation. Flow and diffusion changes in water body was assessed by temperature and dye test. Changes in water floor temperature at 40m intervals was slowly descending over 37 hours. Dye diffusion simulation at 60m intervals, the radius of the spread between two devices were overlapped after 12 hours.

사용 환경조건에 따른 Epoxy/Glass Fiber 복합재료의 표면특성 (Surface properties of epoxy/glass Eber composites by environmental conditions)

  • 임경범;이백수;황명환;김윤선;유도현;이덕출
    • 한국진공학회지
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    • 제9권3호
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    • pp.279-284
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    • 2000
  • 본 연구는 옥외용 epoxy/glass fiber의 열화과정을 분석하기 위하여 FRP 적층판을 고온과 수에 노출시켰다. 열화과정은 접촉각, 표면전위감쇠, 표면저항률의 비교에 의해 평가하였다. 젖음성의 변화는 열처리 시료에서 $200^{\circ}C$까지 접촉각이 증가하였지만 수분처리 시료는 감소하였다. 표면전위감쇠 특성은 수분처리 시료에서는 감소하지만, 열처리 시료는 미 처리와 비교해서 증가하였다. 또한, 표면저항률은 접촉각의 변화와 같은 경향을 보이고 있다.

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Assessing the Impact of Climate Change on Water Resources: Waimea Plains, New Zealand Case Example

  • Zemansky, Gil;Hong, Yoon-Seeok Timothy;Rose, Jennifer;Song, Sung-Ho;Thomas, Joseph
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.18-18
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    • 2011
  • Climate change is impacting and will increasingly impact both the quantity and quality of the world's water resources in a variety of ways. In some areas warming climate results in increased rainfall, surface runoff, and groundwater recharge while in others there may be declines in all of these. Water quality is described by a number of variables. Some are directly impacted by climate change. Temperature is an obvious example. Notably, increased atmospheric concentrations of $CO_2$ triggering climate change increase the $CO_2$ dissolving into water. This has manifold consequences including decreased pH and increased alkalinity, with resultant increases in dissolved concentrations of the minerals in geologic materials contacted by such water. Climate change is also expected to increase the number and intensity of extreme climate events, with related hydrologic changes. A simple framework has been developed in New Zealand for assessing and predicting climate change impacts on water resources. Assessment is largely based on trend analysis of historic data using the non-parametric Mann-Kendall method. Trend analysis requires long-term, regular monitoring data for both climate and hydrologic variables. Data quality is of primary importance and data gaps must be avoided. Quantitative prediction of climate change impacts on the quantity of water resources can be accomplished by computer modelling. This requires the serial coupling of various models. For example, regional downscaling of results from a world-wide general circulation model (GCM) can be used to forecast temperatures and precipitation for various emissions scenarios in specific catchments. Mechanistic or artificial intelligence modelling can then be used with these inputs to simulate climate change impacts over time, such as changes in streamflow, groundwater-surface water interactions, and changes in groundwater levels. The Waimea Plains catchment in New Zealand was selected for a test application of these assessment and prediction methods. This catchment is predicted to undergo relatively minor impacts due to climate change. All available climate and hydrologic databases were obtained and analyzed. These included climate (temperature, precipitation, solar radiation and sunshine hours, evapotranspiration, humidity, and cloud cover) and hydrologic (streamflow and quality and groundwater levels and quality) records. Results varied but there were indications of atmospheric temperature increasing, rainfall decreasing, streamflow decreasing, and groundwater level decreasing trends. Artificial intelligence modelling was applied to predict water usage, rainfall recharge of groundwater, and upstream flow for two regionally downscaled climate change scenarios (A1B and A2). The AI methods used were multi-layer perceptron (MLP) with extended Kalman filtering (EKF), genetic programming (GP), and a dynamic neuro-fuzzy local modelling system (DNFLMS), respectively. These were then used as inputs to a mechanistic groundwater flow-surface water interaction model (MODFLOW). A DNFLMS was also used to simulate downstream flow and groundwater levels for comparison with MODFLOW outputs. MODFLOW and DNFLMS outputs were consistent. They indicated declines in streamflow on the order of 21 to 23% for MODFLOW and DNFLMS (A1B scenario), respectively, and 27% in both cases for the A2 scenario under severe drought conditions by 2058-2059, with little if any change in groundwater levels.

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벼 수잉기내냉성의 전역조건에 따른 변동과 기구 (Changes of Cold Tolerance and it Mechanisms at Young Microspore Stage caused by Different Pre-growing Conditions in Rice)

  • 이선용;박석홍
    • 한국작물학회지
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    • 제36권5호
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    • pp.394-406
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    • 1991
  • 소포자초기의 내냉성이 전역물관리와 시비방법에 따라 변동됨을 실증하고 내냉성의 변동기구를 화분발육생리로 부터 검토한 결과를 요약하면 다음과 같다. 1. 소포자초기의 벼의 내냉성은 유화분화기로부터 소포자초기까지의 수온(전역수온) 및 질소(전역질소)에 의하여 현저하게 변동하였고 유화분화기이전과 소포자초기이후의 수온 및 질소에 따른 변동은 거의 없거나 근소하였다. 영화분화기로부터 소포자초기까지는 10일여에 불과하나 벼의 내냉성소질을 경정하는 중요한 시기였다. 2. 전역물관리에 있어 수온은 $25^{\circ}C$까지 될 수 있는 한 높게. 수심은 10cm까지 될 수 있는 한 깊게 할수록 내냉성이 향상되었으며 이 이상으로 수온상승 및 수심을 깊게하여도 내냉성은 변하지 많았다. 전역수온상승에 따른 내냉성의 향상은 유수가 물로 보호되기 때문이었다. 전역 10cm의 심수관개의 단독효과는 위험기 20cm의 단독효과보다 켰으며 양시기의 심수관개에 따른 냉해방지효과는 상승적이었다. 3. 전역질소의 다량시용에 따른 내냉성의 저하는 엽신의 질소함유율이 어느 한계치를 넘으면 급격히 커졌는데 이 내냉성저하의 변환점에 있어서의 엽신질소 함유율은 일본형에서는 약3.5%, 통일형에서는 약2.5%로 추정되었다. 이 한계엽신질소함유율은 냉해상습지 또는 저온년에 있어서 안전한계시비량을 결정하는 한 지표로 활용될수 있을 것으로 본다. 4. 전역수온상승에 따른 약당충실화분수의 증가는 소포자분화수의 증가에 의한 것이었고 전역질소의 감소에 따른 약당충실화분수의 증가는 소비자의 퇴화에 기인된 것이었으며 충실화분수가 많을수록 임실비율이 높았다.+석회구에서 낮았다 6. 이상과 같은 결과로 미루어 본 실험에 시용된 절대질소량은 많지 않음에도 불구하고 3요소+유기물구는 유기물 분해에 따른 질소의 추비적 효과가 나타나서 무비, 무질소구에 비해 동할미, 심복백미 등 미립의 외관적 특성을 저하시키고, 단백질함량은 높이고 Mg/K\ulcornerNㆍAmylose를 낮추어 식미를 저하시키는 것으로 해석된다 7. 취급특성으로서의 흡수율, 취급액요드정색도, 취급용액출고형물은 처리간 명백한 경향을 발견할 수 없었다. 품종마다 달랐다.분얼'은 출수기가 빨랐으며, 이들은 3일 내에 모두 출수되어 짧은 기간 내에 균일한 출수와 등숙이 이루어짐으로서 미질 향상에 유리할 것으로 해석된다. 변이의 전분산에 대한 기여율은 각각 16.7%와 56.4%로 산지간 변이가 품종간 변이보다 약 4배 가까이 컸다.종과 이앙기를 조절하여 풍해를 회피하거나 방풍림이나 방풍강을 설치하여 풍해를 경감시키는 것이 수량 생산의 안전성을 향상시킬 수 있을 것으로 생각된다.종 육성 보급이 이루어져야 하고, \circled3 품수해 발생상습지에서는 벼 피해를 보상할 수 있는 타작물과의 함리적 작부체계 개선 연구가 이루어져야 하고, \circled4 피해도체의 활용도 증진 연구가 이루어져야 할 것이다. 수 있고 수확량도 크게 증가할 수 있을 것으로 생각된다.들은 진흥과 IR36품종의 중간 영역에 머물고 있었다.mite처리구가 8.6%, 유황첨가구가 5.7~7.4% 증수되었음을 보이었다. 7. 식물체중의 조단백질 함량은 대조구, 5%, 10% 유황첨가구가 3.31~3.50%로서 비슷하였고 15% 유황첨가구는 3.94%,

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