• 한국환경과학회지
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• 제23권9호
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• pp.1551-1562
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• 2014

To clarify the characteristics of TKE (Turbulence Kinetic Energy) variation for offshore wind power development, several numerical experiments using WRF were carried out in three different coastal area of the Korean Peninsula. Buoyancy, mechanical and shear production term of the TKE budget are fundamental elements in the production or dissipation of turbulence. Turbulent kinetic energy of the south coast region was higher than in other sea areas due to the higher sea surface temperature and strong wind speed. In south coast region, strong wind passing through the Korea Strait is caused by channelling effect of the terrain of the Geoje Island. Although wind speed is weak in east coast, because of large difference in wind speed between the upper and lower layer, the development of mechanical turbulence tend to be predominant. Since lower sea surface temperature and smaller wind shear were detected in west coastal region, the possibility of turbulence production not so great in comparison with other regions. The understanding of the characteristics of turbulence in three different coastal region can be reduced the uncertainty of offshore wind construction.

• 한국대기환경학회지
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• 제33권1호
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• pp.19-30
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• 2017

The altitudinal potential source contribution function (PSCFa) method was developed by considering topography and height of back trajectories. The PSCFa calculated on the contributions of trans-boundary transport to the hourly mean concentrations of aerosol optical depth (AOD) of the Aerosol Robotic Network (AERONET) in the Distributed Regional Aerosol Gridded Observation Networks (DRAGON) KORea-US Air Quality (KORUS-AQ) campaign from March 31 to July 1 in 2016. Eastern China ($33^{\circ}N{\sim}35^{\circ}N$ and $119^{\circ}E{\sim}121^{\circ}E$) can be the major source of trans-boundary pollution to the western area in South Korea resulted from PSCFa (0~700 m). In this study, AOD by Moderate Resolution Imaging Spectroradiometer (MODIS) was compared to verify the source regions. Regionally, the effects of the long-range transport of pollutants from the eastern China on air quality in south Korea have become more significant over this period.

• Earthquakes and Structures
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• 제5권1호
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• pp.67-81
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• 2013

Laterite blocks are used for construction of masonry walls since ages in the South-western coastal areas of India. The south-west coastal areas of India lie in zone III of seismic zonation map of Indian code IS 1893-2002. In spite of the fact that laterite is the most favored masonry material in these regions of India, the structural performance of laterite masonry has not been systematically investigated. Again there are no previous studies addressing, in detail, the seismic performance of laterite masonry buildings. Now that these areas are becoming more and more important from point of view of trade and commerce, there is a need for a detailed research on the seismic response of laterite masonry structures located in these areas. The present paper reports the results of such a study of the seismic response of box-type laterite masonry structures. Time history analysis of these structures under El-Centro acceleration has been performed using commercial finite element software ANSYS. Effect of 'containment reinforcement' on the seismic response of box type laterite masonry structures has been evaluated.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2003년도 정기총회 및 추계학술대회
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• pp.259-264
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• 2003

This study aims to understand the architectural characteristics and living pattern of the Daor and to make a comparative study with the Han race. This research inquired into the background of the Daor and surveyed the present condition of traditional houses. As a result of this study, the features of Daor's traditional house is synthesized as follows. 1) The arrangement of village is in a row facing south. The site plan and exterior shape is like as the Manchurian race. 2) Making west window and creating a bright atmosphere is the unique architectural style. 3) Viewed from spatial layout and function, Daor's has more remarkable difference from Han's. That is to say, the room equipped with Kang is daily space and kitchen is just space for cooking in contrast with the Han.

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.311-319
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• 1999

In Korea accelerated industry development and urbanization during the last three decades have led serious water pollution problems in many parts of the nation. Especially in the regions of west and south coast have low fresh water in the dry season of spring and summer. In the place isolated from land it is important to secure the fresh water for drinking and general service. This study is concerned on the thermal system design to develop low-pressure evaporation type fresh water gen-erator of capacity 1 ton/day using the heat source of non-operating boiler in the season of spring and summer. The results obtained from this study are as follows. the water quantitieds generated from experi-mental evaporator showed good coincidence with the calculated values. The maximum production quantity was 1.38ton/day at pressure 40mmHg abs. and temperature $80^{\circ}C$.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 추계학술발표회
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• pp.191-193
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• 2003

본 연구에서는 인공위성 해색센서 SeaWiFS (Sea-Viewing Wide Field-of-View Sensor)에서 관측한 영상을 이용하여 한반도 주변 식물플랑크톤 색소농도의 시공간적 분포 특성에 대하여 살펴보았다. 동해에서 식물플랑크톤 색소농도는 봄철과 가을철에 공간적으로 높은 농도를 나타내었다. 색소농도는 봄철인 4월에 동해 극전선 남부해역에서 가장 높고, 5월에는 극전선 북쪽해역에서 높은 농도가 나타났다. 하계는 거의 저농도를 나타내고 동계가 하계보다 공간적으로 높은 농도를 나타내었다. 그리고 한국 동해안을 따른 warm streamer주변과 서해와 남해연안의 연안선을 따라서 연중 높은 농도가 존재하였다 특히, 여름철 8월부터 12월까지 중국 양쯔강 주린 높은 색소농도가 남해연안 주변까지 연결된 형태로 나타난 것이 특징적이었다.

• 지질공학
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• 제33권4호
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• pp.689-699
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• 2023

Assessing ground stability is critical to the construction of underground transportation infrastructure. Surface displacement is a key indicator of ground stability, and can be measured using interferometric synthetic aperture radar (InSAR). This study measured time-series surface displacement using permanent scatterer InSAR applied to Sentinel-1 SAR images acquired from January 2017 to June 2023 for the area around a deep underground expressway under construction to connect Mandeok-dong and Centum City in Busan, South Korea. Regions of seasonal subsidence and uplift were identified, as were regions with severe subsidence after summer 2022. To evaluate stability of the ground in the construction area, the mean displacement velocity, final surface displacement, cumulative surface displacement, and difference between minimum and maximum surface displacement were analyzed. Considering the time-series surface displacement characteristics of the study area, the difference between minimum and maximum surface displacement since June 2022 was found to be the most suitable parameter for evaluating ground stability. The results identified highly unstable ground in the construction area as being to the north of the mid-lower reaches of the Oncheon-cheon River and to the west of the Suyeong River at the point where both rivers meet, with the difference between minimum and maximum surface displacement of 40~60 mm.

• 한국환경복원기술학회지
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• 제18권6호
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• pp.61-71
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• 2015

The objectives of this study are to construct an ecoregion map and to extract ecological factors from each ecoregion to adapt FLR (Forest Landscape Restoration) of North Korea. An ecological map was constructed by PCA(Principal Component Analysis) and MGC(Multivatiate Geographical Clustering). An ANOVA test verified the differences among ecoregions, and post-hoc pair wise comparisons were performed to determine similarities between them. Factor analysis was conducted to extract ecoregional characteristics. Ecoregions were distributed into clusters reflecting differences of south and north and of east and west of their ecological factors. About 12% of land area in North Korea shared similar ecological factors with South Korea, but the remaining 88% was found to be ecologically different. The ANOVA test showed a p-value of 0.000, indicating significant differences between the regions. Post-hoc pair wise comparisons indicated statistically significant similarities in annual mean temperature between ecoregion D and G, precipitation seasonality between ecoregion H and O, and precipitation of the warmest quarter between ecoregion K and O. Because ecoregion A and N showed same in their soil water contents, they were assumed that the dense of forest cover in the Southern ecoregion A is similar to that in the Northern ecoregion N of Korean peninsular. Based on the results of this study, it is necessary to accommodate quantitative and spatial based planning, when South Korea aids forest restoration projects in North Korea. In addition, it is recommended for both South and North Korea to share on Forest Landscape Restoration methodologies with each other.

• 한국안전학회지
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• 제32권5호
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• pp.157-167
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• 2017

Millions of People die every year from diseases caused by exposure to outdoor air pollution. Especially, one of the most severe types of air pollution is fine particulate matter (PM10, PM2.5). South Korea also has been suffered from severe PM. This paper analyzes regional risks induced by PM10 and PM2.5 that have affected domestic area of Korea during 2014~2016.3Q. We investigated daily maxima of PM10 and PM2.5 data observed on 284 stations in South Korea, and found extremely high outlier. We employed extreme value distributions to fit the PM10 and PM2.5 data, but a single distribution did not fit the data well. For theses reasons, we implemented extreme mixture models such as the generalized Pareto distribution(GPD) with the normal, the gamma, the Weibull and the log-normal, respectively. Next, we divided the whole area into 16 regions and analyzed characteristics of PM risks by developing the FN-curves. Finally, we estimated 1-month, 1-quater, half year, 1-year and 3-years period return levels, respectively. The severity rankings of PM10 and PM2.5 concentration turned out to be different from region to region. The capital area revealed the worst PM risk in all seasons. The reason for high PM risk even in the yellow dust free season (Jun. ~ Sep.) can be inferred from the concentration of factories in this area. Gwangju showed the highest return level of PM2.5, even if the return level of PM10 was relatively low. This phenomenon implies that we should investigate chemical mechanisms for making PM2.5 in the vicinity of Gwangju area. On the other hand, Gyeongbuk and Ulsan exposed relatively high PM10 risk and low PM2.5 risk. This indicates that the management policy of PM risk in the west side should be different from that in the east side. The results of this research may provide insights for managing regional risks induced by PM10 and PM2.5 in South Korea.

• 한국농림기상학회지
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• 제24권2호
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• pp.83-94
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• 2022

농작물 생육 과정에서 서리에 의한 동상해 피해에 능동적으로 대비하기 위해, 지난 21년간(2000~2020) 20개 지역의 서리관측 자료를 이용하여 한국 서리발생의 시공간적 분포 특성을 살폈다. 지역별 서리분포 특성은 서리일수, 첫 서리일, 끝 서리일로 표현하였다. 그리고 이러한 결과의 기후 경향은 Mann-Kendall trend test와 Sen's slope estimator를 수행하여 확인하였다. 한국에서 대부분의 서리는 태백산맥과 소백산맥 서쪽 내륙지방에서 발생한다. 상대적으로 해안지역에 가까울수록 서리 발생일이 적고 첫서리일이 느리며 끝서리일이 빠르다. 동해안지역은 서해안지역보다 서리일수가 적고 첫서리일이 느리며 끝서리일이 빠르다. 남해, 남동해, 도서지역은 거의 서리가 발생하지 않는다. 연간 시계열 추이 분석결과 한국은 기후온난화가 진행됨에도 불구하고, 서리일수가 줄어들거나 첫서리 일이 늦춰지는 경향은 나타나지 않았으며, 끝서리일은 1년에 0.5일씩 늦춰지는 것으로 나타났다.