• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.236-236
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• 2017

본 연구에서는 강우의 시공간성을 파악할 수 있는 격자기반의 Average-point Tracking 프로그램을 이용하여 호우의 DAD(Depth-Area-Duration)를 분석하였다. IPCC 5차보고서에 따르면 1950년 이래로 다수의 극한 기상 및 기후 변화가 관측되었다. 그 중 일부는 인간의 활동과 관련된 것으로 많은 지역에서의 극한 호우 현상의 증가가 손꼽힌다. 이러한 극한 호우 현상 증가와 일부 저수지의 유출 증가 경향은 지역적 규모에서 홍수의 위험이 더 커졌음을 의미한다(Kim et al., 2016). 최근 이상기후 현상의 증가에 따른 강우양상의 변화로 게릴라성 집중 호우와 태풍의 빈도가 증가하고 있지만, 우리나라의 호우의 특성은 방위 및 진행방향에 따른 해석이 매우 복잡하여 강우를 정형화하기에 어려운 특징을 보인다. 또한 지속시간이 긴 호우의 경우에는 호우의 범위가 한반도 전체가 되는 특성 때문에 강우의 시 공간성과 관련된 관측 자료는 부족하며, 이러한 특성을 고려한 연구 또한 미진한 실정이다. 만약, 태풍과 같이 호우이동이 뚜렷한 경우, 기존의 적용되고 있는 유역중심의 DAD 분석 방법으로는 DAD 관계를 명확히 표현하기 어려우며 유역면적이 증가할수록 유역의 면적평균강우량의 오차도 증가하기 때문에 DAD 분석의 정확도는 낮아지게 된다. 따라서 본 연구에서는 호우의 형태와 이동을 고려하기 위해 시간에 따른 호우를 격자로 나누어 격자를 증가시키면서 면적평균최대강우량을 산정할 수 있는 Average-point Tracking 방법을 이용하여 DAD 분석을 실시하였다.

• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.199-204
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• 2013

Despite the suzerain of Korea Taekwondo physical activity and a corresponding lack of basic research on energy consumption and the status of this research is urgent. In this study, the sensor (SenseWear (R) PRO2 Armband), using physical activity were obtained in Taekwondo, and body composition data were obtained by Inbody 520, We were thigh scan using CT scanner and thigh muscle area by CT scan data were acquired. Result of analysis, average thigh muscle area of experimenter 8 people was 132.79 $cm^2$, Of 20 cm above the patella thigh was a 178.79 $cm^2$. Thigh circumference and muscle area showed that the correlation. The average energy consumption per minute was 6.94 calories, and thigh muscle area and average energy consumption per minute also showed that correlation.

• Journal of Korean Society of Disaster and Security
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• v.15 no.3
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• pp.15-21
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• 2022

The purpose of this study is to investigate the sedimentation area and runout distance in the downstream when debris flow occurred on a mountain slope through an experimental performance. Super typhoons and torrential rains caused by climate change cause large-scale debris flow disasters in the downstream areas of mountainous areas, mainly where sediments are deposited and flowed downstream. To analyze the characteristics of the sediment deposited downstream, the disposition area and runout distance were investigated through experiments in the case of a straight channel and channel with berm, respectively. As experimental conditions, changes in sediment volume concentration and channel slope, and channel with or without berm, reduction rates in sedimentation area and runout distance were investigated. In the straight channel, the steeper the channel slope and the lower the sedimentation concentration, the sedimentation area and runout distnace were increased. In a channel with berm, the runout distance and sediment area increased as the slope became steeper and the sediment area decreased.

• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.339-349
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• 2018

The massive green tide occurred every summer in the Yellow Sea since 2008, and many studies are being actively conducted to estimate the coverage of green tide through analysis of satellite imagery. However, there is no satellite images selection criterion for accurate coverage calculation of green tide. Therefore, this study aimed to find a suitable satellite image from for the comparison of the green tide coverage according to the spatial resolution of satellite image. In this study, Landsat ETM+, MODIS and GOCI images were used to coverage estimation and its spatial resolution is 30, 250 and 500 m, respectively. Green tide pixels were classified based on the NDVI algorithm, the difference of the green tide coverage was compared with threshold value. In addition, we estimate the proportion of the green tide in one pixel through the Linear Spectral Unmixing (LSU) method, and the effect of the difference of green tide ratio on the coverage calculation were evaluated. The result of green tide coverage from the calculation of the NDVI value, coverage of green tide usually overestimate with decreasing spatial resolution, maximum difference shows 1.5 times. In addition, most of the pixels were included in the group with less than 0.1 (10%) LSU value, and above 0.5 (50%) LSU value accounted for about 2% in all of three images. Even though classified as green tide from the NDVI result, it is considered to be overestimated because it is regarded as the same coverage even if green tide is not 100% filled in one pixel. Mixed-pixel problem seems to be more severe with spatial resolution decreases.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.207-218
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• 2017

In this study, pitch-based activated carbon fibers (ACFs) were modified with pyrolysis fuel oil (PFO). Carbonized ACF samples were activated at $850^{\circ}C$, $880^{\circ}C$ and $900^{\circ}C$. A scanning electron microscope (SEM) and a BET surface area apparatus were employed to evaluate the indoor radon removal of each sample. Among three samples, the BET surface area and micropore area of ACF880 recorded the highest value with $1,420m^2{\cdot}g^{-1}$ and $1,270m^2{\cdot}g^{-1}$. Moreover, ACF880 had the lowest external surface area and BJH adsorption cumulative surface area of pores with $151m^2{\cdot}g^{-1}$ and $35.5m^2{\cdot}g^{-1}$. This indicates that satisfactory surface area depends on the appropriate temperature. With the above scope, ACF880 also achieved the highest radon absorption rate and speed in comparison to other samples. Therefore, we suggest that the optimum activation temperature for PFO containing ACFs is $880^{\circ}C$ for effective indoor radon adsorption.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1B
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• pp.69-78
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• 2006

The rainfall depth-area-duration analysis which is used to characterize precipitation extremes for specification of so-called design storms, provides a basis for evaluation of drought severity when storm depth is replaced by an appropriate measure of drought severity. So we propose a method for constructing drought severity-area-duration curves in this study. Monthly precipitation data over the whole Korea are used to compute SPI. Such SPIs are abstracted to several independent spatial components from EOF analysis. Using Kriging method, these spatial components are used to constitute grid-based SPI data set over the whole Korea including Jeju island with $6km{\times}6km$ resolution. After identifying main drought events, the drought severity-area-duration curves for these events over 32-year period of record are finally constructed. As a result, such curves show the similar shape with storm-based curves in the sense that the drought severity (or rainfall depth) is inversely proportional to drought area from the curves, but drought-based curves are different from storm-based curves in the sense that the drought severity decreasing rate with respect to drought area is much less than depth decreasing rate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.602-606
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• 1994

The study was conducted to investigate the relationships between the value of fresh leaf lengh ${\times}$ width and actual fresh or cured leaf area, Cured leaf weight of cutter and leaf in Burley tobacco plants. In all tested varieties, Actual fresh leaf area or cured leaf area, cured leaf weight was high significantly correlated with the value of fresh leaf length ${\times}$ width. The linear regression equation between them could be exploited for rapid and easy estimation of either fresh or cured leaf area, cured leaf weight. Highly significant correlation between fresh leaf area and cured leaf area or cured leaf weight was confirmed and a linear regression equation was also obtained for easy estimation of cured leaf area or cured leaf weight.

• Korean Journal of Construction Engineering and Management
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• v.11 no.5
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• pp.41-52
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• 2010

Even though REITs (Real Estate Investment Trusts) are listed on the stock market, REITs have characteristics that allow them to invest in real estate and financing for real estate development. Therefore REITs is related with stock market and construction business and real estate business. Using time-series analysis, this study analyzed REITs in relation to construction businesses, real estate businesses, and the stock market, and derived influence factor of REITs. We used the VAR (vector auto-regression) and the VECM (vector error correction model) for the time-series analysis. This study classified three steps in the analysis. First, we performed the time-series analysis between REITs and construction KOSPI(The Korea composite stock price index) and the result showed that construction KOSPI influenced REITs. Second, we analyzed the relationship between REITs and construction commencement area of the coincident construction composite index, office index and housing price index in real estate business indexes. REITs and the housing price index influence each other, although there is no causal relationship between them. Third, we analyzed the relationship between REITs and the construction permit area of the leading construction composite index. The construction permit area is influenced by REITs, although there is no causal relationship between these two indexes, REITs influenced the stock market and housing price indexes and the construction permit area of the leading composite index in construction businesses, but exerted a relatively small influence in construction starts coincident with the composite office indexes in this study.

• Journal of Navigation and Port Research
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• v.41 no.1
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• pp.17-24
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• 2017

This study uses Conjoint Analysis to study optimal port operations at the newly built International P assenger Terminal (IPT) at Inchon Port, Korea. The perceptions of users, operators, and the Incheon Port Authority are compared and analyzed. The results of user Conjoint Analysis showed that rent calculation method was the most important factor in the NIPT operation plan, followed by establishing automation and the size of the site area. For the Incheon Port Authority and operators, the rent calculation method turned out to be the most important factor for NIPT operation plans. It was followed by establishing automation and the site area. Utility results showed the "investment cost preservation method" to have the highest rent calculation utility, "yard automation" as the priority, and "43,000 pyeong-48,000 pyeong" as the optimal site area.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.184-184
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• 2015

수공구조물의 설계 시 확률강우량의 산정은 매우 중요하다. 따라서 확률강우량 산정을 위한 강우지점의 선정 및 산정방법의 표준화는 매우 중요하다고 할 수 있다. 현재 확률강우량 산정시 대부분은 기상청의 지상기상관측지점과 국토교통부의 산하 지점의 시 단위 또는 일 단위의 강우자료를 활용하여 확률강우량을 산정하고 있다. 또한 면적확률강우량의 산정시에는 원칙적으로 해당 유역내 외에 다수의 관측소 존재 시 Thiessen 가중평균을 이용하여 동시간 임의시간 연최대치 면적강우량자료 계열을 작성하고 빈도해석을 실시해야하지만, 동시간 강우량자료의 수집의 어려움으로 지점 확률강우량을 산정하고 Thiessen 가중평균을 적용 후, 면적우량환산계수를 곱하는 방법을 사용하고 있다. 본 연구에서는 서울의 도림천 유역을 중심으로 기상청의 지상기상관측지점(SSS, Surface Synoptic Stations)과 품질관리를 실시한 방재기상관측지점(AWS, Automatic Weather Stations)의 분 단위 강우자료를 활용하여 강우관측지점 선정과 자료기간에 따른 동시간의 면적확률강우량을산정하고 비교분석하였다. 이는 향후 면적확률강우량 산정방안의 개선 및 보완에 큰 도움이 될 것으로 판단된다.