• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.242-242
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• 2020

도시화와 산업화에 따른 유출환경의 변화로 인해 도심지에서 발생하는 대부분의 유출은 도로표면을 따라 이동하고 도로변에 설치된 빗물받이에 의해 배수된다. 이 때 빗물이 원활하게 배수되지 않아 노면수가 정체되고, 이 노면수가 인근 주택지로 유입되어 침수 피해가 발생한다. 이러한 현상은 유출량이 집중되는 도심지 저지대에서 주로 발생하며 설계 한도를 초과하지 않는 정상적인 강우 조건에서도 빈번히 나타나고 있다. 이는 최근의 기후 변화로 인한 집중 호우 등을 고려하여 설계 기준이 지속적으로 조정되어야 함과 동시에 도로 노면수의 배수 능력 평가를 위한 실제적인 연구가 이루어져야 한다는 필요성을 나타내고 있다. 특히 도로 빗물받이의 효율은 주로 종경사 및 횡경사 등의 도로 조건, 표면 유출 우수량, 빗물받이의 형상 등에 의존한다. 그러므로 상향된 설계빈도 및 도로 조건을 고려한 도로 표면 유출에 대한 흐름 분석과 빗물받이 특성을 고려한 실증연구의 분석 및 설계 해석 알고리즘의 개발이 시급한 실정이다. 본 연구에서는 도로 노면수의 배수 능력 증대를 위해 연속 설치된 빗물받이 조건 및 도로 경사조건을 고려하여 도로 배수시설의 표면 유출 모델 설계 알고리즘을 개발하였다. 표면 유출 유량은 도로의 차선(2~4차선), 경사(종경사 2~10% 및 횡경사 2~10%) 및 설계빈도(최대 30년)를 고려하였으며 유량이 노면 진행방향을 따라 연속적으로 증가하는 부등류 흐름 해석 방법을 채택하였다. 또한, 빗물받이 설치간격(L)과 도로의 폭(W)의 곱으로 계산되는 단순 직사각형 형태의 노면 형상이 아닌 도로 종경사 및 횡경사에 따른 유달거리를 산정하여 평행사변형 형태의 노면 형상을 계산하고 이에 따른 면적(A), 도달시간(tc) 및 강우강도(I)를 산정하였다. 이와 같은 1차원 흐름분석을 통해 도로 표면흐름 및 빗물받이 설치 간격을 제시하고 기존의 제시된 빗물받이 설치 간격과 비교하여 본 연구에서 제시한 설계 알고리즘을 검증하였다. 또한, 수리 실험을 통해 측정된 빗물받이 차집효율을 이용하여 연속 구간에서의 도로 표면 유출 모델의 적용성을 제시하였다. 이는 빗물받이 유입구를 통해 모든 유량이 유출된다고 가정하고 단독 구간에서의 수리분석 결과만을 고려하여 이를 확장시켜 개발된 기존의 도로 표면 유출 모델을 보완할 수 있을 것으로 기대된다. 본 연구에서 제시하고 있는 설계 알고리즘을 적용한다면 도로 전체 구간에서의 흐름 변화 분석과 배수효율의 정량적인 분석이 가능하므로 향후 도로 표면 침수 피해 저감 및 배수능력 증대를 위한 실증적이고 정량적인 분석 방법이 될 것으로 판단된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.469-478
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• 2017

This study analyzed faculties' perceptions on the importance and performance of effective teaching behaviors. The effective teaching behaviors scale consisted of 40 items belonging to 8 factors. A survey was conducted with 86 faculties from 2 universities. It was found that the differences between the importance and performance levels of all items except for 'applying emphasis on important contents' were statistically significant. The scores of importance were higher than those of performance. The results of the IPA showed that 'keep up the good work' area included 19 items that those were high the scores of importance and performance. The 'concentrate here' area included 5 items that need to be improved for effective teaching. The first priority items needing to be improved were 1) Establishing instructional methods and strategies suitable for the objectives, 2) establishing clear objectives, appropriate examples and systematic classes, 3) providing questions, opportunities and appropriate feedback. We suggested that a faculty development program needs to be developed for effective teaching.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.38-45
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• 2015

The risk analysis phase of construction risk management process is subdivided into the qualitative risk analysis that plays a major role, and the quantitative risk analysis acting as a supportive role. The traditional calculation method for quantifying a risk value that has been applied so far is an equation to multiply a probability by an impact simply, but its result shows the low risk value biased distribution. Although another equation that shows the high risk biased distribution as an alternative of traditional method was proposed, both of the low or high risk biased equations do not match with the statistical general knowledge that most natural phenomenons are close to the normal distribution. This study proposes a new risk value calculation method that is concentrated to the moderate risk value. Because the risk value distribution by a new method shows a normal shape similar to natural phenomenon, it helps to choose a middle level not biased to the low or high levels when choosing the level of risk response. Furthermore, it could contribute to improve the flexibility and rationality of risk analysis method by providing additional options for the risk value calculation.

• KDI Journal of Economic Policy
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• v.33 no.3
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• pp.33-55
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• 2011

Market concentration in the Korean banking industry has markedly increased since the financial crisis of 1997-1998 because of M&As, P&As, and consolidation of banks. With this change, there has been a growing concern over market power in the Korean banking sector. We examine the effects of market concentration on bank efficiency and competition for the period of 1992-2006. Three different indicators of bank inefficiency are used in this study, including X-inefficiency that is derived from the directional technology distance function. The level of competition is measured by both the H-statistic of the Panzar-Rosse model and the level of the net interest margin and its standard deviation. Empirical results indicate that market concentration has not improved bank efficiency through scale economies or scope economies. Instead, recent mergers, acquisitions and consolidation of banks resulted in an increase in inefficiency measured by the three different indicators: X-inefficiency, labor inefficiency and asset inefficiency. While an increase in market share of individual banks improved bank efficiency, an increase in the overall market concentration ratio resulted in lower efficiency. Our study also finds that the Korean banking sector has been monopolistically competitive throughout the sample period except for the crisis period according to the H-statistic. Although an increase in market concentration ratio has not changed the overall level of bank competition, it has a positive significant effect on the level of the average interest margin.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.505-505
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• 2023

지진해일의 발생빈도는 태풍이나 홍수 등의 자연재해와 비교하여 발생빈도가 낮지만 발생 시 큰 피해를 입힐 수 있다. 우리나라 동해안은 일본 서해안에서 발생된 지진해일에 취약하며 특히 강원도 삼척시와 경상북도 울진군 부근은 일본 서해안에서 발생된 지진해일 에너지가 집중되는 위험지역으로 기존 연구에서 확인되었다. 동해를 따라 먼 거리를 전파해오는 지진해일 파의 전파양상은 해저수심의 영향을 받아 변화될 뿐만 아니라 진원지의 발생위치와 각 매개변수의 특성에 따라 대상지역에서의 영향도가 다양하게 나타날 수 있다. 본 연구에서는 일본 서해안에서 과거 발생한 지진원(4건) 및 향후 발생 가능한 가상지진원(71건)을 대상 시나리오로 선정하였으며, 가상지진원자료는 한반도 에너지개발 기구(11건) 및 일본토목학회(60건)에서 제시한 총 71건의 자료를 사용하였다. 동해안 해저수심 영향에 의한 지진해일 파 집중도를 확인할 수 있는 파향선추적 기법 수행을 통해 75건 중 집중도가 높은 41건의 지진원을 선정하였다. 선정된 지진원은 불확실성을 고려하기 위해 많은 연구자들에 의해 사용되고 있는 로직트리기법을 적용하여 총 1,107건으로 생성되었으며, 이에 대해 지진해일 수치해석이 수행되어졌다. 최대 지진해일고 비교 결과, 특정 발생위치에서의 지진원은 타 지진원보다 지진강도가 작음에도 불구하고 울진 원자력발전소에서 최대 지진해일고 결과는 더 크게 나타나는 것으로 확인되었다.

• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.739-745
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• 2018

Recently, the incidence of heavy rainfall is increasing. Therefore, a rainfall analysis should be performed considering increasing frequency. The current rainfall analysis for hydrologic design use the hourly rainfall data of ASOS with a density of 36 km on the Korean Peninsula. Therefore, medium and small scale watershed included Thiessen network at the same rainfall point are analyzed with the same design rainfall and time distribution. This causes problem that the watershed characteristics can not be considered. In addition, there is a problem that the temporal-spatial change of the heavy rainfall occurring in the range of 10~20 km can not be considered. In this study, Author estimated design rainfall considering heavy rainfall using minutely rainfall data of AWS, which are relatively dense than ASOS. Also, author analyzed the time distribution and runoff of each case to estimate the huff's method suitable for the watershed. The research result will contribute to the estimation of the design hydrologic data considering the heavy rainfall and watershed characteristics.

• KAPE Magazine
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• s.163
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• pp.6-7
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• 2010

국제 곡물의 주요수출국은 미국, 브라질, 아르헨티나, 호주이다. 실제로는 유통 및 국제 곡물 물류시설을 장악하고 있는 다국적 곡물메이저(4대 메이저: 카길(Cargill), 에이디엠(ADM), 루이스드레피스(Louis Dreyfus, LDC), 벙기(Bunge)에 의한 집중도가 증가하고 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.372-379
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• 2019

This study analyzed the thoughts of college life of students enrolled in each admission process to determine the level of academic competency. The satisfaction level of university life was analyzed among university students who studied at Dongguk University in 2012-2017 and the results were compared with the difference in importance and concentration of university life. Finally, the differences in scholastic ability around GPA were analyzed and compared. The results showed that students with pre-school grades were more satisfied with their college life than those with regular admissions. Although satisfaction with education is high during college life, it has been shown to be unsatisfactory regarding scholarships that are closely related to life. In terms of the difference between importance and concentration of college life, the greatest concern was with finding employment after graduation, but in reality the students could not focus on the current situation, but focused only on the current situation of grades and teamwork. The final admission GPA also showed that pre-school students were higher than regular students, and were able to adjust quickly to their school life and affect their satisfaction. Overall, education policies and programs are needed to understand the overall thoughts of university life and supplement them.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.2 s.36
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• pp.77-88
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• 2006

Overpopulation has been one of the most serious problem of the Seoul Metropolitan Area (SMA), which consists of the City of Seoul, Incheon, and the whole of Gyeonggi Province. People have been still moving into SMA, especially being concentrated into the fringe of Seoul. This study examines the inner city decline phenomenon of SMA which can be easily found in large cities over the world, based on the demographic data of these area. In addition, this study monitors the imbalance in growing of SMA by analyzing RMI (Rank Mobility Index), and the inverse relation between the self sufficiency of the adjacent area and the commuting rate to Seoul by analyzing commuting data. Even though the total population has been unchanged, the internal change of population was substantial. The growth of Seoul Metro region was placed near the city of Seoul, especially commuter data reassured the population concentrations. The results will be useful in urban planning and growth management.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.330-339
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• 2017

In Korea, metropolitan cities and provinces are responsible for setting up their own Regional Forest Plans to manage the forests at regional scales distinguished by administrative boundaries, and the role of the plans are very crucial by linking the Forest Basic Plan for nationwide forest management policy with Forest Management Plans for local-level forest management practices. Thus, the analysis of forest resources at regional levels is required to make more efficient regional forest plans by properly reflecting regional forest situations. This study aims to present which species are concentrated at each individual metropolitan city or province, contributing to more efficiently establishing its regional forest plan. In order to measure the concentration levels of species for each region, Location Quotient and Relative-Specialization Index are computed using area- and volume-data for the major species selected in the Statistical Yearbook of Forestry. As a result, the ranks among the indices of the major species for each individual municipal city and province are presented. The results from this study can contribute to the selection of regional target species and establishment of regional forest management objectives. Further study regarding the differences between the results from area-based and volume-based indices will be helpful to consider regional level productivity by species into the regional forest plans.