• 한국토양비료학회지
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• 제48권5호
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• pp.379-383
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• 2015

Indicators of environmental conditions describe the state of the environment and the quantity and quality of natural resources. This study deduced the evaluation items to assess each sub-indicator for agricultural water quality and conducted the surveying using the Delphi method based on agricultural water quality experts. Considering its importance, environmental, state, and management indicators showed that state indicator such as COD concentration for surface water and $NO_3-N$ concentration for groundwater was ranked as first and followed by amount of fertilizer. Its indicators were correlated with state and environmental indicators in surface water and groundwater. The best management indicators were calculated to assess the agricultural surface water and ground water quality. The indicator could be used in established policies for management and conservation of water resources.

• 한국과학교육학회지
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• 제22권2호
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• pp.215-229
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• 2002

이 연구에서는 물의 상태와 상태 변화 및 상태변화의 조건을 중심으로 유치원, 초등, 중등 과학 교재의 내용을 분석하고자 하였다. 이를 위하여 유치원 제 5차 교육과정 교재들과 제 6차 교육과정에 근거한 초등학교 자연 교과서와 중학교 과학 교과서를 분석하였다. 개념의 학년별 전개를 주제형 계열화와 나선형 계열화에 비추어 분석한 결과, 일부 내용은 적절하게 구성되었으나, 일부 내용은 부적절한 것으로 나타났다. 그리고 학년이 증가함에 따라 개념은 지각적 인식 수준, 거시적 현상 이해 수준과 용어 인식 수준, 리고 미시적 개념 이해 수준으로 전개되었음을 알 수 있었다. 그러나 응고와 융해 등 상태변화 중 일부개념과 열, 온도, 바람, 습도, 기압 등 상태변화의 조건에서는 미시적 개념 이해 수준의 전개가 이루어지지 않았다. 그리고 상태변화 개념과 열, 바람 등 일부상태변화의 조건 개념에서는 용어 인식 수준의 내용도 전개되지 않았다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.203-203
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• 2016

The linkage between climate change and water security, i.e., the response of water resource to the future climate change, have been of great concern to both scientific community and policy makers. In this study, the impact of future climate on water resources in Yellow River Basin in North of China has been investigated using the Coupled Land surface and Hydrology Model System (CLHMS) and IPCC AR5 projected future climate change in the basin. Firstly, the performances of 14 IPCC AR5 models in reproducing the observed precipitation and temperature in China, especially in North of China, have been evaluated, and it's suggested most climate models do show systematic bias compared with the observation, however, CNRM-CM5、HadCM5 and IPSL-CM5 model are generally the best models among those 14 models. Taking the daily projection results from the CNRM-CM5, along with the bias-correction technique, the response of water resources in Yellow river basin to the future climate change in different emission scenarios have been investigated. All the simulation results indicate a reduction in water resources. The current situation of water shortage since 1980s will keep continue, the water resources reduction varies between 28 and 23% for RCP 2.6 and 4.5 scenarios. RCP 8.5 scenario simulation shows a decrease of water resources in the early and mid 21th century, but after 2080, with the increase of rainfall, the extreme flood events tends to increase.

• 환경정책연구
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• 제5권4호
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• pp.19-49
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• 2006

기후변화가 지역의 수자원에 영향을 미칠 것으로 예상됨에 따라 수자원 관리자들은 이에 대응한 적응전략을 수립하는 것이 필요하다. 이에 본고에서는 미국, 영국, 캐나다, 오스트렐리아, 네덜란드의 적응관리의 실태를 검토하였다. 이들 나라들은 현재의 수자원 관리관행, 제도적 장치, 기후변화의 잠재적 수자원 영향에 따라 매우 상이한 적응관리를 하고 있다. 이들 나라들의 비교연구를 통하여 기후변화에 따른 한국에서의 지속 가능한 수자원 관리를 위한 정책적 관련성을 도출하였다.

• 대한치과보철학회지
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• 제37권2호
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• pp.256-268
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• 1999

Submerged implants require secondary surgical uncovering of implants after healing period of 3-6 months. In surgical methods, there are surgical scalpel, tissue punch, electro-surgical, and laser-used uncovering, and so forth The objectives of this study are investigation and assessment of 1) thermal change in clinical application for uncovering of HA-coated implant and pure titanium implant irradiated by pulsed Nd-YAG, $CO_2$, and Er-YAG laser. 2) surface change of cover screws aaer irradiation using laser energy. The temperature of apex & side wall of implants were recorded at 10sec, 20sec, 30sec after 30sec irradiation to implant healing screw; 1) pulsed Nd-YAG laser; 2W, 20pps, contact mode 2) $CO_2$ laser; water-infused & non-water infused state, 2.5-3.5W, contibuous mode, noncontact mode 3) $CO_2$ laser ; non-water infused state, 3W, superpulse, noncontact. mode 4) Er-YAG laser; (1) non-water infused state, 10pps, 60mj, contact mode (2) water-infused state, 10pps, 60mj, 80mj, 101mj, contact mode. According to the results of this study, pulsed Nd-YAG laser is not indicated because of increased thermal change and pitting of metal surface of implant cover screw. By contrast, $CO_2$ laser & Er-YAG laser are presumed to indicate because of narrow range of thermal change & near abscence of thermal damage of metal surface. Dental laser is thought to be much helpful to surgical procedure when it is used as optimal power and time condition considering characteristics and indications of each laser. Further research is needed to verify that these techniques are safe and beneficial to implant success.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1419-1419
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• 2005

• 대한가정학회지
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• 제19권1호
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• pp.39-45
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• 1981

The fishes that are mostly used in our homes such as Pacific Mackeral, hair Tail and Alaska Pollack were devided into Freezing group, Refrigerating group and Room temperature group according to storage temperature. TVB-N, TMA-N, TMA-O and pp.H. were measured in natural state, after water washing and 3% NaCl-water washing. The results are as follows: 1. Regardless of the kinds of fishes, TVB-N in room temperature showed that rottenness first appeared after 5~8 hours in raw state, 6~12 hours in water washing, and 8~12 hours in 3% NaCl-water washing. 2. Regardless of freezing and refrigeration, Pacific Mackeral became rotten after 14 days in raw state, 14~17 days in water washing and 17 days in 3% NaCl water washing. Alaska Pollack and Hair Tail showed rottenness after 8 days in raw state, 11 days in water and 3% NaCl water washing. 3. Even in hot summer days, freshness could be preserved for 10 days if fishes were freezed ($-20^{\circ}C$) or refrigerated (4~$8^{\circ}C$) after bowel excluded, washed in NaCl water and enveloped in poly-ethylene bag.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.15-21
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• 2007

Due to a decreasing tendency of river runoff in the Laohahe River basin in North China, quantitative analysis was made with the aid of the conceptual Xinanjiang model under the background of nature climate variability as well as human-induced climate change according to the long-term observational hydrometeorological data. In the past, the human effect on surface water resources was estimated by investigating the impact of human activities on each item in the equation of water balance, so as to calculate water quantity of each item in the original natural status. It seems to be clear conceptually. It is appropriate just for the case of direct impact, such as water transfer from one basin to another, water storage by various scales of hydraulic projects, besides a huge amount of investigation and indeterminate statistics data when applied in practice. It is difficult for us to compute directly water consumption due to the implementation of measures for soil conservation, the improvement of farming techniques in agriculture, the growth of population in towns and villages, and the change of socioeconomic structure. In view of such situation, the Xinanjiang model was used to separate human impact from the climatic impact on water resources. Quantitatively human activity made river runoff decrease by 1.02, 50.67, 58.06 mm in 1960's, 1970's, 1980's, respectively, while by 97.2 mm in 1990's in the sense of annual average in the Laohahe River basin.

• Water Engineering Research
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• 제4권1호
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• pp.31-43
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• 2003

The impacts of climate change on soil moisture in sub - Arctic watershed simulated by using the hydrologic model. A range of arbitrary changes in temperature and precipitation are applied to the runoff model to study the sensitivity of soil moisture due to potential changes in precipitation and temperature. The sensitivity analysis indicates that changes in precipitation are always amplified in soil moisture with the amplification factor for flow. The change in precipitation has effect on the soil moisture in the catchment. The percentage change in soil moisture levels can be greater than the percentage change in precipitation. Compared to precipitation, temperature increases or decreases alone have impacts on the soil moisture. These results show the potential for climate change to bring about soil moisture that may require a significant planning response. They are also indicative of the fact that hydrological impacts affecting water supply may be important in consider-ing the cost and benefits of potential climate change.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1418-1419
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• 2007

In order to check the electric field distribution of polymer line post insulator, we performed electric field simulation according to state of water drops. Sea water is used to the contaminant. Electric field analysis is performed with change of contact angle, number and distance of water drops.