Synthesis and characterization of a triple cross-linked PVA/methacrylate kappa-carrageenan hydrogel encapsulated with a chitoologosaccharide: Potential wound-healing characteristics

Tae-Hee Kim,Pathum Chandika,Min-Sung Kim,Fazlurrahman Khan,Young-Mog Kim,Seong-Yeong Heo,Gun-Woo Oh,NamGyun Kim,Won-Kyo Jung 한국수산과학회 양식분과 2021 한국수산과학회 양식분과 학술대회 Vol.2021 No.4

Numerical study on debris flow behavior at a series of check dams

( Namgyun Kim ) 대한지질공학회 2016 대한지질공학회 학술발표회논문집 Vol.2016 No.0

Selection of Reinforcement Method in the Region of Seismic Land Creep by Analysis of Slope Stability

( Namgyun Kim ),( Jaehwan Kwak ),( Man-il Kim ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

On November 15, 2017, land creep and slope failure occurred in slope of Yongheung-dong, Pohang, Korea due to the earthquake of magnitude 5.4. As the possibility of further damages of study area is expected, the geological characteristics were analyzed and proper countermeasure was selected through analysis of slope stability. To investigate the characteristic of geology and topography, various survey techniques such as surface geological survey, drilling survey, groundwater level measurement, electrical resistivity survey, and field penetration test were applied. Also, the limit equilibrium analysis was performed on the four representative sections using the surveyed data. The minimum safety factor was applied based on the conditions of dry season, wet season, and earthquake, according to the slope design criterion of construction slope announced by Korea’s Ministry of Land, Infrastructure and Transport, Korea. All four sections were analyzed to have a slope failure risk in case of earthquake and one section were analyzed to have a slope failure risk in case of wet season. The shape of the slope failure was thin and long. Therefore, it was suggested that it is appropriate to establish a countermeasure for preventing collapse due to slipping of slope. Acknowledgement This research was supported by the Korea Agency for Infrastructure Technology Advancement under the Ministry of Land, Infrastructure and Transport of the Korean government. (Project Number: 19SCIP-C151408-01)

CAE 기법을 활용한 EPS의 EMC CE 해석과 표준화 방법

김남균(Namgyun Kim),이두진(Doojin Lee),Neeraj Tripathi,Sushrut Kelkar,황재신,진종학 한국자동차공학회 2023 한국자동차공학회 학술대회 및 전시회 Vol.2023 No.11

CAE 기법을 통해 EPS의 EMC CE 해석을 하는 방법을 소개하고 시제품 제작 전 실제 제품과의 Correlation 할 수 없는 경우 해석의 유효성 확보를 위해 해석 모델 표준화 방법에 대해서 소개한다. It introduces how to perform EMC CE analysis of EPS through CAE techniques and how to standardize the analysis model to ensure the validity of the analysis when it cannot be correlated with the actual product before prototyping.

벨리 스팅 모형 지지부의 간섭 효과 보정기법 연구

김남균(Namgyun Kim),안승기(Seung-Ki Ahn) 한국항공우주학회 2002 韓國航空宇宙學會誌 Vol.30 No.8

토석류 수치해석에서 지형자료와 유출량 적용에 관한 연구

김남균(Namgyun Kim),전병희(Byonghee Jun) 한국방재학회 2023 한국방재학회논문집 Vol.23 No.6

This study used an unmanned aerial vehicle (UAV) for aerial photogrammetry at the Seonseri debris flow site in Gokseong-gun, triggered by heavy rainfall in August 2020. Survey data facilitated the generation of orthographic images and high-resolution digital surface mode (DSM). Finite difference method (FDM) numerical analysis simulated debris flow, exploring the impact of discharge rate and topographic data among input variables. Applying the rational formula for determining debris flow discharge rate emphasized the significance of maximum rainfall intensity just before the event, with high estimated values for runoff coefficient and soil concentration. The study highlighted significant variations in debris flow simulation results based on topographical data accuracy, emphasizing the crucial role of precise site-specific topographical data. 본 연구에서는 2020년 8월 집중호우로 인하여 곡성군 선세리 일대에서 발생한 토석류 현장을 무인항공기(Unmanned Aerial Vehicle, UAV)를 이용하여 항공사진측량을 실시하였다. 측량자료를 이용하여 정사영상과 고해상도 DSM (Digital Surface Mode)을 생성하였다. 현장조사를 통하여 토석류로 인한 침식과 퇴적상황을 확인하고, 토석류 범람범위를 정확하게 실측하였다. 토석류 시뮬레이션을 위해 유한차분 수치해석을 실시하였으며, 입력자료 중 토석류 유량과 지형자료의 영향을 검토하였다. 토석류 발생유량 결정에 합리식 적용시 토석류 발생직전 최대 강우강도가 중요하며, 적용되는 유출계수, 토사농도도 높은 값으로 추정되었다. 지형자료에 따라 토석류 시뮬레이션 결과가 크게 달라지는 것을 보였으며, 정확한 현장의 지형자료를 이용하는 것이 매우 중요함을 보였다.

양간지풍 특성을 고려한 동해안 대형 산불의 수치시뮬레이션

김남균(Kim, Namgyun),곽재환(Kwak, Jawhwan),김만일(Kim, Man-Il) 한국방재학회 2021 한국방재학회논문집 Vol.21 No.4

강원도 동해안 지역은 양간지풍의 특성으로 인해 봄철 산불 발생시 대형 산불로 확산될 가능성이 높다. 2000년 동해안 산불, 2005년 양양산불, 2019년 고성 산불이 이러한 양간지풍의 영향을 받아 대형 산불로 기록된 사례이다. 양간지풍은 3월~4월 봄철 한반도 남쪽에서의 저기압과 북쪽에서의 고기압이 배치가 되어 발생한 서풍이 발생한다. 발생된 서풍은 태백산맥을 넘어 고온 건조하고 강한 풍속을 지닌다. 정부에서는 동해안 지역의 대형 산불 위험성이 높아짐에 따라 산불방지센터를 설치하여 적극적인 대응을 수행하고 있다. 하지만, 자연 환경을 제어하고 제한된 장비와 인력을 투입하는 것은 한계가 있다. 따라서 본 연구에서는 과거 동해안 산불의 사례조사를 통해 특징을 분석하고, 2019년 고성에서 발생한 산불의 사례에 대하여 2차원 수치모델을 이용해 확산을 예측하였다. 예측된 산불 확산은 실제 산불 확산 범위와 방향을 비슷하게 예측하였으며, 지형정보의 구체화와 연료 정보의 구체화를 통해 모델을 개선하면 보다 정확한 산불의 확산을 예측할 수 있다고 판단된다. 이러한 수치해석 정보를 구축하면, 산불 발생시, 지역주민의 대피나 자원의 배치 등 효율적인 대응을 할 수 있을 것으로 예상된다. The east coastal region in Gangwon-do, Korea, has a high risk of large forest fires in the spring owing to the local wind called Yangganjipung. The East Coast forest fire of April 2000, the Yangyang forest fire of April 2005, and the Goseong forest fire of April 2019 are examples of large-scale forest fires caused by Yangganjipung. In the spring, the low pressure in the south and the high pressure in the north in Korea result in a western wind. This western wind is called Yangganjipung, and it exhibits characteristics of high temperatures, dryness, and high wind speeds over the Taebaek Mountains. Given that the risk of large forest fires is high in the east coastal region, the local government has established a forest fire prevention center to respond efficiently to such events. However, limitations pertaining to controlling the natural environment and limited equipment and workforce exist. In this study, the characteristics of previous forest fires in the east coastal region were analyzed through case studies, and two-dimensional numerical simulations of the Goseong forest fire of April 2019 were performed. The spreads of the predicted and actual forest fires were similar. In addition, forest fire spreading can be predicted more accurately if the model is improved by clarifying the terrain and fuel details. An effective plan for providing evacuation routes and resource allocation to mitigate large forest fires can thus be achieved using numerical simulation results.

무인 항공 사진측량을 이용한 절토사면의 땅밀림 시계열 분석

김남균 ( Namgyun Kim ),최봉진 ( Bongjin Choi ),최재희 ( Jaehee Choi ),전병희 ( Byonghee Jun ) 대한지질공학회 2020 지질공학 Vol.30 No.4

연구지역인 강원도 삼척시 도계읍의 사면은 지형변화가 발생하는 지역으로 2009년 사면 절취공사를 수행하여 사면경사완화공법이 적용되었다. 하지만 사면의 상부에 위치한 폐석적치장의 영향으로 2개월뒤 절취사면의 상부를 확장하여 안정성을 도모하였다. 최근 사면 하부에 위치한 옹벽의 배부름 현상이 발견되고 절취사면의 균열이 나타나 지형변화가 다시 발생하고 있는 것으로 보이고 있다. 이러한 문제를 파악하기 위하여 본 연구에서는 UAV를 이용하여 사진측량을 수행해 지형변화가 발생하는지 확인하고자 하였다. 2019년 4월과 10월 각각 정사영상을 추출하고 Digital Surface Model(DSM)를 추출하여 고해상도의 지형변화를 비교 분석하였다. 10월의 지형은 4월의 지형형상을 그대로 유지한채 앞으로 밀려 나간 모습을 보여 이러한 지형변화는 땅밀림인 것으로 분석하였다. The study area is a slope in Dogye-eup, Samcheok-si, Gangwon-do. The cutting method was applied to this slope for stabilization in 2009 due to the influence of the waste-rock dump located at the top of slope. Recently, soil cracks and creep have occurred on this slope, and the drainage channel was damaged. Therefore, it was analyzed the topography change through photogrammetry using a UAV. Orthophotos were taken in April and October 2019 respectively. From the Orthophots, Digital Surface Model (DSM) was extracted. Time series analysis was performed by comparing each DSM. The topography of October was pushed forward while maintaining the topography of April. Through these features, it is judged that the soil creep is occurring in this study area.

초등 수학 개방형 과제의 해법 공간 분석 연구

김남균 ( Kim NamGyun ),김수지 ( Kim Su Ji ),송동현 ( Song Dong Hyun ),오민영 ( Oh Min Young ),이현정 ( Lee Hyun Jung ) 한국수학교육학회 2022 初等 數學敎育 Vol.25 No.1

The purpose of this study is to develop a framework for analyzing the solution spaces of open-ended task and to explore their usefulness and applicability based on the analysis of solution spaces constructed by students. Based on literature reviews and previous studies, researchers developed a framework for analyzing solution spaces (OMR-framework) organized into subspaces of outcome spaces, method spaces, representation spaces which could be used in structurally analyzing students’ solutions of open-ended tasks. In our research, we developed open-ended tasks which had various outcomes and methods that could be solved by using the concepts of factors and multiples and assigned the tasks to 181 elementary school fifth and sixth graders. As a result of analyzing the student's solution spaces by applying the OMR-framework, it was possible to systematically analyze the characteristics of students' understanding of the concept of factors and multiples and their approach to reversible and constructive thinking. In addition to formal mathematical representations, various informal representations constructed by students were also analyzed. It was revealed that each space(outcome, method, and representation) had a unique set of characteristics, but were closely interconnected to each other in the process. In conclusion, it can be said that method of analyzing solution spaces of open-ended tasks of this study are useful for systemizing and analyzing the solution spaces and are applicable to the analysis of the solutions of open-ended tasks.

SCFQ 스케쥴링 알고리즘의 구현 및 성능 분석

김남균(Namgyun Kim),김영한(영역),신명기(Myung-Ki Shin),함진호(Jin-Ho Hahm) 한국통신학회 1998 한국통신학회 학술대회논문집 Vol.1998 No.7