• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.521-521
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• 2012

우리나라는 산악지역이 국토의 대부분을 차지하고 있어 전체유역을 놓고 볼 때 대하천이 차지하는 부분보다는 중소하천이 차지하는 부분이 상대적으로 크고, 교량의 길이가 짧은 소교량이 수적으로 많은 부분을 차지하고 있다. 그중에서도 특히 중소하천의 유량은 시간적으로 매우 빠르게 변화하며 유속 또한 급속히 빨라져 하상의 변형이 순식간에 일어나고 있다. 이와 같은 시간적, 공간적인 호우특성과 지형특성으로 인하여 중소하천에 위치한 교량은 특히 세굴에 매우 취약함을 보여주고 있다. 하천에 건설되는 교량의 수명이나 안정성에 세굴이 미치는 영향은 매우 크며, 특히 우리나라와 같이 홍수 시 단기간에 걸쳐 유량이 급증하는 경우 유속에 의한 교량 기초의 급격한 세굴은 예상치 못한 교량 붕괴 사고를 초래할 수 있다. 현재 국내 소하천에 설치된 교량은 약 3,470개소(지방도 기준)로 다양한 하부구조로 설계되어 있다. 이렇게 하천 내에 세워진 교량과 같은 횡단 구조물들은 그 크기에 상관없이 하천의 형태에 영향을 미치게 된다. 그중에서 교량 세굴은 하천 횡단구조물로 인하여 발생되는 가장 중요한 문제 중의 하나로써 교량 건설 시 교각에 영향을 주는 세굴을 예측하고 방어하기 위하여 다양한 방정식을 통하여 신설교량의 교각세굴을 예측한다. 하지만 대부분의 교량 세굴 공식들은 실험실에서의 실험 결과를 토대로 개발되었기 때문에 이들 공식들이 산정한 국소 세굴량이 얼마나 정확한지는 실제 현장 관측 자료와의 비교를 통해서만 검증할 수 있다. 세굴 공식들의 산정 결과를 현장 실측자료와 비교하는 연구는 그 동안 다양하게 시도되었으나, 통일된 결론에는 도달하지 못하고 있다. 본 연구에서는 기존의 세굴깊이 산정 시 일반적으로 사용되어지고 있는 세굴공식들 중 소하천 교량 규모에 적용 가능한 공식들을 선별하고, 각 세굴심 추정공식에 속한 변수별 특성분석을 위하여, 5가지의 독립변수를 설정하여 국부세굴의 현장 측정값과 예측공식의 비교결과에 대하여 불일치율을 비교분석하였다. 그 결과, 모든 공식들의 불일치율의 기하 평균이 1보다 큰 것을 보여주고 있다. 즉, 모든 공식들이 과대 추정의 의미로 정확성면에서 우수한 공식들은 불일치율의 기하 평균이 1에 가깝고 기하 표준편차가 작은 공식들이 나타났으며, 이런 점에서 Froehlich 공식, Inglis-Poona II, Blench-Inglis I, Breusers 공식 등의 기하평균이 1에 가장 근접한 결과를 나타내었다. 각 세굴공식 세굴심 산정결과의 불일치율을 각각 5가지의 변수별로 도시하여 분석하였으며, 그 결과로 소하천에 대하여 적용 가능한 공식과 소하천에 적용 시에는 과다추정의 우려가 있는 공식으로 분류되어 면밀한 검토가 필요할 것으로 판단된다.

• Journal of Korean Society of Disaster and Security
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• v.15 no.3
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• pp.41-46
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• 2022

Recently, the scale of flood damage occurring in urban areas is increasing due to climate change and urbanization, so various flooding analysis techniques are needed. In the Sadangcheon Stream basin, which has been continuously flooded since 2010, a basic plan for improving drainage was established using XP-SWMM and measures to prevent flooding were proposed. However, in the process of inundation analysis, the analysis considering the city's buildings was not conducted, resulting in a problem that the degree of flooding damage tends to be overestimated. Therefore, in this study, XP-SWMM was used to compare and analyze cases where buildings were not considered and designated as inactive areas. As a result of the study, it was analyzed if the building was not considered, the flood damaged area was 271,100 m² and the depth of submersion was 0.15 m, and if the building was considered inactive area, the flood damaged area was 172,900 m² and the depth of submersion was 0.32 m that it is under-estimated about 36% and an flow velocity around the building increased from 1.62 m/s to 1.83 m/s about 1.12 times.

• The Journal of the Korea Contents Association
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• v.8 no.12
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• pp.375-385
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• 2008

As hotel industry lately recognize that food and drink industry produces more profits than hotel rooms, multi-various and scientific management policies are required along with the management of profitability. Particularly, as hotel services have become more alike due to the development of technology and sharing information, opportunities for differentiation have decreased. Human resource is a significant key for the hotel business as it could lead to a success or failure. It would be overwhelming for employees if they carry all the burdens on their shoulders to impress the customers and improve the service culture in this fast-changing society with different colors of human desire. Therefore, it is essential to focus on developing strategies of efficient organizational as well as human resource management, and the managerial leadership with capability of understanding the organizational structure should play the leading role, considering the specific characteristics of hotel business. The purposes of the study are transformational leadership and transactional leadership comparison analysis of hotel F&B to management strategy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.13-22
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• 1985

A study was undertaken to evaluate the nutritional quallity of protein from precooked seafoods. Procedures for evaluation included protein efficiency ratio(PER) using the rat, computed PER(C-PER) and discriminant computed PER(DC-PER) techniques. These procedures involve the determination of in vitro digestibility and amino acid composition of the sample prior to computation of C-PER and CD-PER value in laver was higher. For the oyster, the C-PER value was very close to the PER value obtained from the rat assay. The difference between DC-PER value and rat-PER or NPR was slightly lower than that between C-PER and rat-PER except oyster and laver. Seafood samples which posses a high in vitro protein digestibility may need the DC-PER procedure could offer more advantages in predicting the protein quality of seafood samples than the DC-PER procedure which showed poor in vitro digestibility.

• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.771-786
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• 2006

Imha lake has a high turbid water which keeps up during a few months, as comparing to other dams. Origins of the high turbid water derive from suspended materials which compose of micro particles of clay and rock-forming minerals. They are the weathered products from surface rocks that relate with particular geology in drainage field of the Imha dim. Accordingly we have fundamentally surveyed the kinds, properties, distribution and structures of general geology, found a few particular geology that source clay materials, and traced the passage that their weathered products enter the dam. We have suggested the basic origins of increase in turbid degree from detecting kinds and behavior of the suspended materials cause high turbid water in the Imha lake.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1489-1493
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• 2008

신규 수자원개발을 위해서는 사회적으로 공감대를 형성해야 하며, 사업을 평가할 수 있는 기준과 방법이 객관성과 타당성을 가져야 한다. 이를 위해 수자원개발 사업시 대상이 되는 편익과 비용을 제시하여 계량화하는 것이 필요하다. 수자원사업에 따른 편익 및 비용의 대상 항목과 그 필요성은 기존에 이미 정립되어 있으나 용수공급과 홍수조절, 수력발전 등 일부 항목에 대한 계량화만이 비교적 실체적으로 연구되었을 뿐이다. 그러나 최근의 사회적 여건변화에 따라 환경개선, 관광 및 레크리에이션, 주운 등 다양한 편익항목의 계량화 방안 개발이 요구되고 있다. 본 연구에서는 댐에 의한 환경개선용수공급에 따른 하천수질개선 편익의 계량화 방안을 제시하고자 한다. 댐에 의한 하천의 수질개선은 크게 두 가지 측면에서 바라볼 수 있는데 하천유량 증대에 따른 희석효과와 수처리 시설에 의한 정수효과가 그것이다. 본 연구는 댐으로부터 공급되는 풍부한 유량을 바탕으로 희석효과에 의한 하류 수질개선 편익을 계량화하기 위한 것이다. 즉, 풍부한 유량으로 유량감소에 따른 수질악화를 막고, 희석작용에 의한 자정작용의 향상 및 이에 따른 수질개선 효과에 대한 편익이다. 본 연구는 이를 위하여 낙동강수계 내에 신규댐 건설에 의한 하류 수질개선 편익을 산정하고자 한다. 기존에는 환경개선용수 공급을 위한 댐의 편익산정에 대체댐에 의한 대체시설비용법을 적용하였으나, '댐을 대체하는 또 다른 댐'에 의한 편익산정이 갖는 이론적 모순이 제기될 수 있어 설득력을 갖기 힘든 면이 있었다. 따라서 본 연구에서는 댐의 환경개선용수 공급을 통한 수질개선 효과를 산정한 후, 이에 상당하는 효과를 환경기초시설에 의해 구현하였을 때의 비용을 계산하여 환경개선용수 공급의 편익으로 가정하는 대체시설비용법을 제시하였다.

• Journal of the Korean earth science society
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• v.26 no.7
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• pp.661-667
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• 2005

It was preliminarily considered that Jangdo wetland was a concave landform formed by the weathering of granite intruding Precambrian silicified metasedimentary rocks. Various granite-weathered topography was observed. The formation scenario of Jangdo wetland is as follows. By flood or slope mass movement of regolith, rock fragments were moved to form a low-relief slope landform. As a result, wetland was formed. By analyzing the slope soil and wetland sediment, we conjectured that Jangdo wetland depended on the influence of peripheral slope soil. In these concavelandform environment, the supply of water and organic materials was sustained for a long time to form a organicnondegradable wetland environment. In addition, the plants appropriate to this wetland environment were settled to thicken the wetland. This is how the present Jangdo wetland was thought to be formed.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.27-32
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• 2005

DEM is needed for urban modeling, forecasting of floods and the analysis of slope and aspect. It has been generated using digital maps, aerial photos or satellite imageries. Recently, however, many studies on DEM generation from LiDAR data has been conducted because of its efficiency and accuracy. Filtering is said to be the process of making DEM by eliminating non-ground points from LiDAR data. In most researches, some input parameters such as the size of filter are required. The purpose of this investigation is to automatically obtain DEM by eliminating objects of various sizes without the knowledge of the objects' sizes. The experimental results show that most of objects on steep terrain are eliminated by the proposed method.

• Journal of Korean society of Dental Hygiene
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• v.15 no.5
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• pp.841-847
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• 2015

Objectives: The purpose of the study was to investigate the satisfaction with instruction medium according to learner attitude and lecture mode in the dental hygiene students. Methods: A web-based self-reported questionnaire was complected by 155 dental hygiene students in Cheonan from May 26 to June 5, 2015. The questionnaire consisted of general characteristics of the subjects, school adaptation, interest to learn, effort to learn, faculty centered lecture, learner centered lecture, self-directed learning, motivation to learn, characteristics of each subject, and satisfaction with lecture mode. The study was approved by institutional review board (IRB) by Baekseok University. Chi-square test and multivariate logistic regression were used to evaluate the satisfaction to medium of instruction according to explanation factors. Results: The lecture mode, opportunity and motivation to learn, interest to learn and effort to learn were the significant factors to satisfaction with instruction medium. In multivariate logistic regression model, the adjusted odds ratio was 6.28 for the opportunity to learn and 4.87 for the interesting to learn. Conclusions: The satisfaction with instruction medium is the most important factor that decides the lecture mode and learner attitude including opportunity to learn and concern to learn.

• Journal of Korea Water Resources Association
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• v.42 no.9
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• pp.703-713
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• 2009

Dam has very important roles in both water use and flood control. Dam release and runoff from rainfall affect directly to the flood control at the downstream of dam during heavy storm especially. This study evaluates the applicability of a distributed model by applying the GRM (Grid based Rainfall-runoff Model) based on HyGIS (Hydro Geographic Information System) environment to runoff modeling at the downstream of dam where the discharge from dam and rainfall affect simultaneously. In order to do this, Yeoju watershed in Han River basin is selected. Rainfall data and discharge from Chungju regulation dam and Hoengseong dam are applied to runoff simulation. The modeling results are verified with Yeoju water level station, and they show good agreement with observed hydrographs. And this study shows that GRM is able to simulate appropriately the effect of dam discharge and rainfall on watershed runoff.