• Journal of the Korean Institute of Gas
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• v.18 no.1
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• pp.17-24
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• 2014

LNG storage tank is a facility to store liquefied natural gas (LNG) and its safety and stability to be greatly needed. When there is a LNG leakage in case of primary container problem, a special facility such as a bund wall should be constructed to store the leaked LNG. But this method makes the land usage inefficient and construction price high. So nowadays the full containment type LNG storage tank is selected instead of constructing a bund wall. In the full containment type tank, the concrete sidewall has the ability to store LNG temporarily. There are largely two methods to give the concrete sidewall the ability. In a method, rebar should be used when constructing the side wall of the LNG storage tank. In the other method, the protecting material such as sprayed polyurethane foam should be applied on the inner surface of the concrete sidewall. Sprayed PUF keeps the temperature of the sidewall above the specified temperature during the specified periods. Recently the thermal stability reinforcing method using sprayed polyurethane foam has been applied to all LNG storage tank built in Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.58-69
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• 2007

The vegetation area that occupies 76% in land surface of the earth can give a considerable impact on water resources, environment and ecological system by future climate change. The purpose of this study is to predict future vegetation cover information from NDVI (Normalized Difference Vegetation Index) extracted from satellite images. Current vegetation information was prepared from monthly NDVI (March to November) extracted from NOAA AVHRR (1994 - 2004) and Terra MODIS (2000 - 2004) satellite images. The NDVI values of MODIS for 5 years were 20% higher than those of NOAA. The interrelation between NDVIs and monthly averaged climate factors (daily mean, maximum and minimum temperature, rainfall, sunshine hour, wind velocity, and relative humidity) for 5 river basins of South Korea showed that the monthly NDVIs had high relationship with monthly averaged temperature. By linear regression, the future NDVIs were estimated using the future mean temperature of CCCma CGCM2 A2 and B2 climate change scenario. The future vegetation information by NOAA NDVI showed little difference in peak value of NDVI, but the peak time was shifted from July to August and maintained high NDVIs to October while the present NDVI decrease from September. The future MODIS NDVIs showed about 5% increase comparing with the present NDVIs from July to August.

• Journal of Conservation Science
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• v.34 no.5
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• pp.397-405
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• 2018

Currently, there are very few studies on Korean wall paintings. Therefore, this study discusses the current conditions of wooden paintings and the characteristics of the adhesive agent in the painting layer separation. Korean land pine was chosen as the support, while white oysters shells, orpiment, red ocher, Noerok, and azurite were used as pigments. With four adhesive agents, including animal glue, Gelidium, methyl cellulose, and PVAc (caparol binder), a comparative experiment was conducted, by dividing them into two concentrations, of 0.5% and 1.5%. The temperature, humidity, and ultraviolet rays, which are contributing environmental factors in cultural assets after fixing, were artificially investigated. After deterioration, observed color difference, fixing, and the surface. Results showed that the animal glue strongly fixing all the colored layers compared to the other adhesives; however, azurite had a partial change when used outdoors. With Gelidium, which functioned similar to animal glue, the azurite was affected by the ultraviolet rays; nevertheless, despite the variations in temperature and humidity, it had the best gripping force compared to the other adhesive agents. Methyl cellulose was glossy at a high concentration, and was relatively strong against rapid changes in temperature and humidity. PVAc significantly reduced the binding force, compared to other adhesive agents.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.3
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• pp.51-61
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• 2020

Drought events are not clear when those start and end compared with other natural disasters. Because drought events have different timing and severity of damage depending on the region, various studies are being conducted using satellite images to identify regional drought occurrence differences. In this study, we investigated the applicability of drought assessment using the Evaporative Stress Index (ESI) based on Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images. The ESI is an indicator of agricultural drought that describes anomalies in actual and reference evapotranspiration (ET) ratios that are retrieved using remotely sensed inputs of Land Surface Temperature (LST) and Leaf Area Index (LAI). However, these approaches have a limited spatial resolution when mapping detailed vegetation stress caused by drought, and drought hazard in the actual crop cultivation areas due to the small crop cultivation in South Korea. For these reasons, the development of a drought index that provides detailed higher resolution ESI, a 500 m resolution image is essential to improve the country's drought monitoring capabilities. The newly calculated ESI was verified through the existing 5 km resolution ESI and historical records for drought impacts. This study evaluates the performance of the recently developed 500 m resolution ESI for severe and extreme drought events that occurred in South Korea in 2001, 2009, 2014, and 2017. As a result, the two ES Is showed high correlation and tendency using Receiver Operating Characteristics (ROC) analysis. In addition, it will provide the necessary information on the spatial resolution to evaluate regional drought hazard assessment and and the small-scale cultivation area across South Korea.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.219-219
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• 2011

순 장파복사량은 지표면으로 입사되는 하강 장파복사량(Downward Longwave Radiation, $R_{ld}$)과 지표면에서 반사되는 상승 장파복사량(Upward Longwave Radiation, $R_{lu}$)의 차이로 정의되는데 이는 에너지 수지 및 농업기상 연구의 중요한 주제 중 하나로서 다루어져 온 순복사량의 중요한 요소이다. 일반적으로 $R_{lu}$의 경우 지표면 온도와 방사율(emissivity)를 이용하여 산출되므로 정확히 추정이 가능하나, $R_{ld}$의 경우 대기 최상층에서 관측되는 방사량과 지표면 근처의 방사량을 함께 고려해야 하므로 실측이 어렵다. $R_{ld}$는 야간 복사계(pyrgeometer)를 이용하여 직접적으로 측정할 수 있지만 관측기기 자체가 구비되어있는 관측소가 적어 매우 드물게 이용된다. 또한 단파 복사 에너지 측정 기기에 비해 비용이 많이들고 종종 관측값이 큰 오차를 가지고 있기 때문에 실무에 적용하기 힘든 단점이 있다. 따라서 기상 관측소에서 얻어지는 증기압과 온도 관측치를 물리식, 경험식 등에 적용하여 산정하게 된다. 현재는 $R_{ld}$의 추정은 관측된 방사량간의 관계를 나타내는 경험식을 기반으로 지표면 근처의 대기 온도와 습도를 이용하여 산출하는 방법이 널리 사용되고 있다. 본 연구에서는 증발산 산정 알고리즘 개발의 시발점으로써 $R_{ld}$를 먼저 구하고 $R_{lu}$를 구하였다. 신뢰성 높은 방법을 이용하여 $R_{ld}$를 구하게 되면 정확도 높은 $R_N$을 구하는 데 기여할 수 있으며, 궁극적으로 보다 정확한 증발산을 산정할 수 있게 된다. $R_{ld}$는 일반적으로 clear sky 조건 하에서의 복사 에너지 플럭스($R_{ldc}$)를 구한 후 구름의 양에 따라 보정한다. 하강 장파복사량의 경우 널리 사용되는 공식 중 하나인 Brutsaert의 공식을 사용하였다. 광릉, 해남에 위치한 플럭스 타워지점에서 실측된 기온과 실제 수증기압을 입력인자로 사용하여 지점별 $R_{ldc}$를 먼저 구하고 Moderate Resolution Imaging Spectroradiometer(MODIS) 영상자료를 이용하여 검증한 뒤 최종적으로 남한지역을 대상으로 순 장파복사량 지도를 작성하였다. 이를 위해 MODIS 07 대기 프로파일 산출물(Atmospheric Profile Product)중 기온 및 이슬점온도를 추출하여 산정식의 입력자료로서 사용하였다. 상승 장파복사량의 경우 MODIS 11 지표면 온도 산출물(Land Surface Temperature product)를 이용하여 산정하였다. 이는 남한 지역의 증발산량 추정 및 에너지 수지 연구를 위한 중요한 기본 자료로서 유용하게 사용될 수 있으리라 사료된다.

• Journal of Satellite, Information and Communications
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• v.11 no.4
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• pp.94-101
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• 2016

Satellite data for remote sensing technology has limitations, especially with visible range sensor, cloud and/or other environmental factors cause missing data. In this study, using land surface temperature data from the MODerate resolution Imaging Spectro-radiometer(MODIS), we developed retrieving methods for satellite missing data and developed three methods; mean bias, regression analysis and local variation method. These methods used the previous day data as reference data. In order to validate these methods, we selected a specific measurement ratio using artificial missing data from 2014 to 2015. The local variation method showed low accuracy with root mean square error(RMSE) more than 2 K in some cases, and the regression analysis method showed reliable results in most cases with small RMSE values, 1.13 K, approximately. RMSE with the mean bias method was similar to RMSE with the regression analysis method, 1.32 K, approximately.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.57-60
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• 2008

According to the recent tendency that the buildings in the downtown concerning rising land prices and efficient use of building are gradually Manhattanized mainly the grand scaled residential buildings, structure of the buildings relates to safety and so the very thick mat concrete is selected as the foundation of architectures. Because mat concretes can not be simultaneously pour in a great quantity due to the circumstance at the field, not only the questions on the unification between the concretes pour on the upper layer and the lower layer are presented but also the cracks by the internal force from the difference of hydration exothermic period are occurred because of the time lag. Thus, this study checked the efficiency to apply "The hydration heat controlling method of mass concrete for horizontal partition pouring construction" to the skyscraper sites under construction at Haiundai in Busan. After applying this method, the result of observation that the cracks by hydration heat in all over the placement surface did never be founded. Also, in case of the economic analysis that the hydration heat reduction method using super retarding agent by difference of setting time is approximately 80% cheaper than the hydration heat reduction method by pipe cooling in the construction expenses.

• Ocean and Polar Research
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• v.34 no.2
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• pp.197-199
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• 2012

According to the IPCC climate change scenario (A1B scenario), the surface seawater temperature of the South Sea of Korea by 2100 may be $2-3.5^{\circ}C$ higher than at present, and seawater pH may decrease from 8.1 to 7.8, due to the increase in atmospheric $CO_2$, which is predicted to increase in concentration from 380 to 750 ppm. These changes may not only intensify the strength of typhoons/storm surges but also affect the function and structure the marine ecosystem. In order to assess the impact of climate change on the marine ecosystem in Korean waters, the project named the 'Assessment of the impact of climate change on marine ecosystem in the South Sea of Korea' has been supported by the Ministry of Land, Transport and Maritime Affairs, from 2008. The goal of this project is to enhance our ability to adapt and prepare for the future environmental changes through the reliable predictions based on the knowledge obtained from projects like this. In this respect, this project is being conducted to investigate the effects of climate/marine environment changes (ocean warming and acidification), and to predict future changes of the structure and function of the ecosystem in the South Sea of Korea. This special issue contains 6 research articles, which are the highlights of the studies carried out through this project.

• Journal of Wetlands Research
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• v.8 no.1
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• pp.49-58
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• 2006

Drought is an natural phenomenon which effects greatly on our society. It has various time scale and it is difficult to define the beginning and the end. So we can't aware it quickly and the damage of drought become severe. To cope with these problems, it needs to construct drought monitoring system. And it is required that the definition of drought which is objective and can be applied widely and proper drought index for drought monitoring. Meteorology and hydrology have developed drought index for drought monitoring. There are many attempt to interpret the drought using NDVI(Normalized Difference Vegetation Index) or LST(Land Surface Temperature) in remote sensing. In this study, drought index and precipitation is used to find drought severity of last ten years in South Korea. NDVI and VCI is applied to perceive the state of drought. Finally, the possibility of drought monitoring and evaluating drought depth is estimated by analyzing the correlation between vegetation Index and drought index.

• Journal of the Korean Geographical Society
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• v.45 no.5
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• pp.573-591
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• 2010

In this study, trends of heat waves in the populous Seoul metropolitan area over the last 100 years (1908-2007) and spatio-temporal patterns of extreme heat waves and excessive human mortality are examined. In spite of recent global warming, there is no observable increasing or decreasing pattern in the frequency and intensity of heat waves in Seoul due to increases of summer precipitation. Among numerous episodes over the last 100 years in Seoul, 1994 summer is recognized as the unprecedented, most extreme hot episode with long-lasting, intense heat waves Meteorological data observed at the Automatic Weather Stations (AWS) and land surface temperature data derived from Landsat TM satellite imagery in July 1994 reveal that extreme heat waves cause more abnormal increase of elderly mortality in the urbanized areas than in the surroundings covered with more vegetation. This study provides bioclimatological evidences of why urban thermal environments should be seriously considered in the future urban revitalization planning.