• 한국농공학회논문집
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• 제53권3호
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• pp.1-11
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• 2011

The temporal variability of spring (March, April, May) monthly precipitation, precipitation effectiveness, monthly maximum precipitation, monthly precipitation of different durations, and the precipitation days over several threshold (i.e. 0, 10, 20, 30, 40, and 50 mm/day) of 59 weather stations between 1973 and 2009 were analyzed. Also to analyze the regional characteristics of temporal variability, 59 weather stations were classified by elevations, latitudes, longitudes, river basins, inland or shore (east sea, south sea, west sea) area and the level of urbanization. Results demonstrated that trends of variables increase in April and decrease in May except precipitation day. Overall trend of precipitation amount and precipitation effectiveness is same but precipitation effectiveness of several sites decrease despite the trend of precipitation amount increases which may be caused by the air temperature increase. Therefore more effective water supply strategy is essential for Spring season. Regional characteristics of Spring precipitation variability can be summarized that increase trend during May become stronger with the increase of latitude and elevation which is similar to that of Summer season. The temporal variability of variables showed different behaviors according to river basins, inland or shore (east sea, south sea, west sea) area and the level of urbanization.

• 한국농공학회논문집
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• 제54권4호
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• pp.115-125
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• 2012

The comparison between the spatial and temporal variability of aridity index, precipitation effectiveness and runoff during El-Nino and La-Nina periods and that of the normal period was conducted to evaluate the regional impacts of El-Nino, La-Nina in hydrologic variables. Aridity index and precipitation effectiveness were estimated using 59 nationwide weather stations data and runoff data of WAMIS were used. The ratio of the difference between El-Nino, La-Nina year value and that of normal year was analyzed. Temporal variation demonstrated that aridity index, precipitation effectiveness and run-off discharge increase in March, April, August, November, December and decrease in February, June, September, October according to El-Nino effect. Aridity index, precipitation effectiveness and run-off discharge increase in March, May, September and decrease in June, August, November, December according to La-Nina effect. The spatial variation of those variables analyzed for different basins showed that impacts in the Han river basin relatively higher than that of other basins.

• 한국수자원학회논문집
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• 제44권8호
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• pp.683-694
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• 2011

기후변화에 따른 지역적 영향인 기온 상승과 강수량 변화로 인한 수자원 변화 특성을 파악하기 위하여 기상청(KMA)으로부터 전국 59개 관측지점에 대해서 1973년부터 2009년까지 강수량 및 기온자료를 이용하여 산정한 강수효율자료와 국가수자원관리종합시스템(WAMIS)으로부터 1966년부터 2007년까지 PRMS 모의 유출량 자료를 수집, 분석하였다. 분석결과, 전반적으로 강수효율의 거동은 강수량의 변화 특성을 따르나 지역적으로 강수량이 증가함에도 불구하고 기온 상승에 따라 강수효율이 감소하는 거동을 보였으며, 이는 유출량의 변화 특성과 유사하였다. 또한 유출량의 평균대비 변화율은 강수량 변화보다 상당히 크게 나타나, 기후변화의 영향에 민감한 것으로 나타났다. 강수량이 증가하는 5월~9월을 제외한 전체 기간에 대하여 강수효율은 강수량보다 더 유의한 감소 경향을 나타내고 있어 해당기간의 가용 수자원량이 줄어들 것으로 판단되며, 이러한 특성은 봄, 가을 및 겨울철 수자원 관리에 반영되어야 할 것이다.

• 한국물환경학회지
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• 제31권1호
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• pp.19-28
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• 2015

The purpose of this research is reconstruction of annual precipitation based on Tree-ring series at Seorak mountain and examine its effectiveness. To do so we performed nonlinear time series characteristics test of Tree-ring series and reconstructed annual precipitation of Gangneung from 1687 to 1911 using Artificial neural network and Nonlinear autoregressive exogeneous input (NARX) model which reflects stochastic properties. As a result, Tree-ring series at Seorak Mountain shows nonlinear time series property and reconstructed annual precipitation series drawn from NARX is similar in statistical characteristics of observed annual time series.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.148-148
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• 2022

Spatiotemporal precipitation data is one of the primary quantities in hydrological as well as climatological studies. Despite the fact that the estimation of these data has made considerable progress owing to advances in remote sensing, the discrepancy between satellite-derived precipitation product (SPP) data and observed data is still remarkable. This study aims to propose an effective deep learning model (DLM) for bias correction of SPPs. In which TRMM (The Tropical Rainfall Measuring Mission), CMORPH (CPC Morphing technique), and PERSIANN-CDR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks) are three SPPs with a spatial resolution of 0.25o exploited for bias correction, and APHRODITE (Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation) data is used as a benchmark to evaluate the effectiveness of DLM. We selected the Mekong River Basin as a case study area because it is one of the largest watersheds in the world and spans many countries. The adjusted dataset has demonstrated an impressive performance of DLM in bias correction of SPPs in terms of both spatial and temporal evaluation. The findings of this study indicate that DLM can generate reliable estimates for the gridded satellite-based precipitation bias correction.

• 한국소프트웨어감정평가학회 논문지
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• 제15권2호
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• pp.59-66
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• 2019

제주는 농업과 관광이 절대적 비중이므로 강수에 대한 예측/분석은 다른 지역보다 더 중요한 요소로 작용한다. 현재 제주도의 강수 예측은 기상위성을 통해 얻어지는 관측데이터에 수치모델을 이용하나, 다른 지역보다 강수 현상에 대한 변화가 다양하므로 기존의 일반적인 수치모델을 그대로 적용하여 강수 예측/분석을 하기는 쉽지 않고 만족할만한 결과를 얻기가 어렵다. 따라서 제주지역에 맞는 새로운 제주 예측/분석 방법이 연구돼야 할 것이다. 본 논문에서는 합성곱신경망 (Convolution Neural Network, CNN) 기반의 텍스처(Texture) 분석기법을 이용한 제주 강수패턴 분석 방법을 제안한다. 제안하는 방법은 기상위성에서 획득한 제주도 영역에 대한 수증기영상과 지역의 온도정보를 텍스처 영상으로 변환한 후, 변환된 영상들을 합성곱신경망을 이용하여 강수 여부를 분석하는 방법이다. 제안한 방법을 구현하고 실험을 통하여 제안된 방법의 유효성을 보인다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.226-231
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• 2002

The present study discusses the results of the controlled precipitation of HgTe nanocrystals in a PbTe semiconductor matrix and demonstrates its effectiveness in producing well-organized and crystallographically aligned semiconductor nanocrystals. Following the similar procedure used in metallic alloys, the semiconductor alloys are treated at 600$^{\circ}C$ for 48 hours, quenched and aged up to 500 hours at 300$^{\circ}C$ and 450$^{\circ}C$ to induce homogeneous nucleation and growth of HgTe nanocrystalline precipitates. Examination of the resulting precipitates using transmission electron microscopy (TEM) and high resolution TEM (HRTEM) reveals that the coherent HgTe precipitates form as thin discs along the {100} habit planes making a crystallographic relation of {100}$\sub$HgTe///{100}$\sub$PbTe/ and [100]$\sub$HgTe///[100]$\sub$PbTe/. It is also found that the nato-disc undergoes a gradual thickening and a faceting under isothermal aging up to 500 hours without any noticeable coarsening. These results, combined with the extreme dimension of the precipitates (4 nm in length and sub-nanometer in thickness) and the simplicity of the formation process, leads to the conclusion that controlled precipitation is an effective method for the preparation of the desirable quantum-dot nanostructures.

• 대한화학회지
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• 제54권3호
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• pp.338-349
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• 2010

이 연구에서는 중학교 3학년에 가르치는 일정성분비의 법칙과 관련된 앙금생성실험수업과 모형을 이용한 수업의 효과를 비교하였다. 연구 대상은 중학교 3학년 250명이었으며, 각각 앙금생성 실험반과 모형반으로 구분하였다. 연구 결과, 앙금생성 실험반은 수용액 안에 각각의 원소들이 분리되어 있다고 생각하는 비율이 상대적으로 높았으며, 두 용액을 섞으면 새로운 화합물이 만들어진다고 인식하는 비율도 모형반보다 높았다. 앙금생성에 대한 학생들의 인식에는 두 집단이 큰 차이가 없었으며, 오답의 비율이 높아 교수전략이 학생들의 인식을 교정하는데 효율적이지 못함을 확인하였다. 비록 실험 결과로부터 규칙성을 찾는 비율은 모형을 사용하는 집단이 높았지만, 실험 결과로부터 반응물 사이의 일정비 결합을 추론하는 학생들의 비율은 두 집단이 유사하였다. 이러한 연구 결과를 통해 실험과 모형을 통해 일정성분비를 추론하는 것은 중학생의 수준에서 쉽지 않다는 점을 알 수 있다.

• 한국환경과학회지
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• 제19권6호
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• pp.787-797
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• 2010

Nowadays meteorological information is systemized as a useful knowledge which has a significant effect on the overall industrial domains over the simple data. The distribution industry, which has the short life cycle, depends on the meteorological information at the strategic level. However, it is necessary to pay attention to the continuous investment in meteorological information because there is a hostility to paying for a service, particularly it does not provide accurate and reliable information. Therefore, the purpose of this study is to increase the usefulness of meteorological information in the distribution industry for its economic effectiveness from the core meteorological factors. We found significant meteorological factors (temperature, precipitation, disaster) that have a critical influence on the distribution industry through the hierarchical analysis process, and their importance according to the type of distribution channels, such as department store, large-scale discount store, convenience store, and home shopping. We performed the AHP analysis with 103 survey samples by middle managers from the various distribution channels. We found that precipitation is the critical meteorological factor across the distribution industry. Based on this result, we stress the difference in the level of the meteorological information in order for the effectiveness of each type of distribution channels.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.67-71
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• 2009

본 논문에서는 우리나라에서 동일한 환경에 설치되어 있는 247.5kW bulk형 모듈과 a-Si형 모듈의 6월 발전량을 조사 분석하여 기상조건(일조량, 평균기온, 강수량, 운량, 풍속 등)과의 관계를 분석하고 최근 지구온난화 등으로 인한 기후변화에 따라 보다 고효율적인 모듈 산정방안을 제시하였다.