• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.533-534
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• 2012

전 세계적으로 지구 온난화 문제가 빠른 속도로 확산되고 있는 가운데 태양전지 또는 풍력발전기를 이용한 발전 시스템이 심화 되어 지구환경 문제와 에너지 문제를 해결하는 수단으로 큰 기대를 받고 있다. 본 논문에서는 Zigbee와 Bluetooth 기반의 센서 네트워크 기술을 복합 발전기 모니터링 분야에 적용하여 무선 통신 네트워크를 구성하는 것을 목표로 한다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.55-61
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• 1999

최근 국내외적으로 지구온난화, 산성비, 오존층파괴 등의 환경문제가 심각하게 대두되기 시작하면서 화석연료 사용에 대한 규제가 점차적으로 강화되고 있다. 이와같은 상황에서 기존의 미분탄 화력발전시스템에 비해서 NOx, SOx, $CO_2$, 분진 등의 대기오염물질을 현저히 줄일 수 있으며 발전효율도 높아서 석탄 사용에 따른 지구의 환경오염 저감과 에너지의 효율적인 이용 측면에서 석탄가스화 복합발전 시스템은 청정석탄 이용기술로 크게 관심을 모으고 있어서 국내외적으로 관련연구가 활발히 진행중이다.(중략)

• 한국지구물리탐사학회:학술대회논문집
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• 2010.10a
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• pp.133-134
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• 2010

• The Journal of Engineering Geology
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• v.33 no.2
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• pp.307-322
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• 2023

Rock-mass grouting plays a crucial role in the construction of dams and deep caverns, effectively preventing seepage in the foundations, enhancing stability, and mitigating hazards. Most rock grouting is affected by hydrogeological and rock engineering indices such as rock quality designation (RQD), rock mass quality (Q-value), geological strength index (GSI), joint spacing (Js), joint aperture (Ap), lugeon value (Lu), secondary permeability index (SPI), and coefficient of permeability (K). Therefore, accurate geological analysis of basic rock properties and guidelines for grouting construction are essential for ensuring safe and effective grouting design and construction. Such analysis has been applied in dam construction sites, with a particular focus on the geological characteristics of bedrock and the development of prediction methods for grout take. In South Korea, many studies have focused on grout injection materials and construction management techniques. However, there is a notable lack of research on the analysis of hydrogeological and rock engineering information for rock masses, which are essential for the development of appropriate rock grouting plans. This paper reviews the current state of research into the correlation between the grout take with important hydrogeological and rock engineering indices. Based on these findings, future directions for the development of rock grouting research in South Korea are discussed.

• The Journal of Engineering Geology
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• v.33 no.4
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• pp.701-716
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• 2023

Microplastics (<5 mm diameter) in aquatic environments adsorb heavy metals, potentially exposing humans to their toxic effects via food chains. We investigated factors influencing the adsorption of heavy metals on microplastics in aquatic environments, examining their adsorption processes and mechanisms. Adsorption characteristics vary with polymer type, crystallinity, particle size, and environmental conditions (pH, temperature, weathering), and the adsorption capacity for heavy metals increases with weathering and reduction in polymer particle size. However, correlations between environment temperature, polymer crystallinity, and adsorption capacity for heavy metals could not be confirmed. The adsorption behavior of heavy metals can be explained in terms of physicochemical adsorption processes and evaluated through adsorption kinetics and isothermal studies, with multiple mechanisms usually being involved. An understanding of the adsorption of heavy metals by microplastics should aid evaluation of the potential risks of microplastics in aquatic environments.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.05a
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• pp.15-20
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• 2005

기존의 GIS와 지구통계기법을 결합한 연구들은 GIS 데이터베이스로 구축될 자료를 생성하기 위해 2차원 접근방식을 이용해왔다. 그러나 실제 현장 샘플 자료들은 대부분 3차원 공간에 분포하기 때문에 2차원 지구통계기법을 적용하는 것은 실제 자료가 가지고 있는 3차원 위치정보를 정확히 반영할 수 없는 한계가 있다. 본 연구에서는 GIS 기반 자료에 3차원 지구통계기법을 적용하여 공간변수를 예측하고, 생성된 공간변수를 다시 GIS로 반환하여 데이터베이스로 구축하는 결합 모델을 개발하였다. 3차원 지구통계기법을 결합한 결과 보다 정확한 공간변수 예측을 확인할 수 있었고, 그 결과를 GIS에서 다시 활용할 수 있었다.

• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.26.2-26.2
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• 2010

이 연구는 Ashen light 측정을 통해 전 지구 반사율을 구하는 통합적 광선 추적 모델을 구성하고 그 수치모사 성능을 검증하는데 목적을 두고 있다. 통합적 광선 추적 모델은 태양-지구-달 시스템에 대하여 태양 복사에너지의 광경로를 추적함으로써 최종적으로 저궤도 상에 존재하는 광학계에 도달하는 Ashen light과 moonshine의 조도를 수치 모사하는 기법이다. Ashen light은 구형의 태양에서 출발한 $1.626\times10^{26}W$의 에너지를 가지는 400nm에서 700nm 파장대역의 빛이 램버시안 특성을 지니는 구형의 지구에서 반사된 후 램버시안 특성을 가지는 구형의 달에서 재 반사되어 저궤도상의 광학계로 입사하는 빛이고, moonshine은 달에서 직접 반사되어 저궤도상의 광학계로 입사하는 빛이다. 통합적 광선 추적 수치 모사를 이용하여 구한 Ashen light과 moonshine의 조도는 1차 근사 해석적 방법을 이용한 계산 결과와 측정 오차 범위 이내의 오차를 보였다. 최종 연구 결과 Ashen light과 moonshine의 조도를 이용하여 구한 지구 반사율과 1차 근사 해석적 방법을 이용한 지구 반사율 계산의 결과가 유사함을 증명하였다.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.379-394
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• 2021

Air pollution data in South Korea is provided on a real-time basis by Air Korea stations since 2005. Previous studies have shown the feasibility of gridding air pollution data, but they were confined to a few cities. This paper examines the creation of nationwide gridded maps for PM10 concentration using 333 Air Korea stations with variogram optimization and ordinary kriging. The accuracy of the spatial interpolation was evaluated by various sampling schemes to avoid a too dense or too sparse distribution of the validation points. Using the 114,745 matchups, a four-round blind test was conducted by extracting random validation points for every 365 days in 2019. The overall accuracy was stably high with the MAE of 5.697 ㎍/m³ and the CC of 0.947. Approximately 1,500 cases for high PM10 concentration also showed a result with the MAE of about 12 ㎍/m³ and the CC over 0.87, which means that the proposed method was effective and applicable to various situations. The gridded maps for daily PM10 concentration at the resolution of 0.05° also showed a reasonable spatial distribution, which can be used as an input variable for a gridded prediction of tomorrow's PM10 concentration.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.543-557
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• 2021

Because aerosols have different spectral characteristics according to the size and composition of the particle and to the satellite sensors, a comparative analysis of aerosol products from various satellite sensors is required. In South Korea, however, a comprehensive study for the comparison of various official satellite AOD (Aerosol Optical Depth) products for a long period is not easily found. In this paper, we aimed to assess the performance of the AOD products from MODIS (Moderate Resolution Imaging Spectroradiometer), VIIRS (Visible Infrared Imaging Radiometer Suite), Himawari-8, and Sentinel-3 by referring to the AERONET (Aerosol Robotic Network) sun photometer observations for the period between January 2015 and December 2019. Seasonal and geographical characteristics of the accuracy of satellite AOD were also analyzed. The MODIS products, which were accumulated for a long time and optimized by the new MAIAC (Multiangle Implementation of Atmospheric Correction) algorithm, showed the best accuracy (CC=0.836) and were followed by the products from VIIRS and Himawari-8. On the other hand, Sentinel-3 AOD did not appear to have a good quality because it was recently launched and not sufficiently optimized yet, according to ESA (European Space Agency). The AOD of MODIS, VIIRS, and Himawari-8 did not show a significant difference in accuracy according to season and to urban vs. non-urban regions, but the mixed pixel problem was partly found in a few coastal regions. Because AOD is an essential component for atmospheric correction, the result of this study can be a reference to the future work for the atmospheric correction for the Korean CAS (Compact Advanced Satellite) series.

• The Bulletin of The Korean Astronomical Society
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• v.25 no.1
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• pp.52-52
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• 2000