Graphite-Sulfur Composite에서 관측된 저자기장 마이크로파 흡수

이창훈 조선대학교 생산기술연구소 2007 生産技術硏究 Vol.29 No.2

Graphite-sulfur conposite에 대한 전자상자성 공명 연구 결과 일반적인 전자상자성공명신호와 더불어 매우 분명한 마이크로파 흡수 저자기장에서 관측되었다. 이에 저자기장 마이크로파 흡수는 시료 내에 미시적으로 존재하는 초전도 특성에 의한 약한 조셉슨 효과에 의한 것으로 설명하였고, g-인자 2 근처에서 관측된 전자상자성공명 신호는 황의 표면 흡착과정에서 발생한 sp_(2) 결함에 의한 것으로 해석하였다. 미시적으로 존재하는 초전도 특성은 특히 Cu_(n)C_(60)에서 이미 보고된 결과와 매우 유사함을 알 수 있었다. Low-field microwave absorptions and their hysteresis behavior as well as an normal electron paramagnetic resonance (EPR) transition are reported for graphite-sulfur composite. The microwave absorption is considered as a consequence of a microscopic disthbution of Josephson weak-links in graphite-sulfur composite, and the EPR transition is explained by the localized spin defects induced by sulfur treatment on graphite. A very close phenomenological resemblance between graphite-sulfur composite and Cu_(n)C_(60) with weak superconductivity was also discussed.

수중 통신에 관한 연구

이강훈(Kang-Hoon Lee),백명숙(Myeong-Sook Back),장남주(Jang-Nam Ju),이창의(Chang-Ui Lee),김미경(Mi-Kyung Kim),박철수(Chul-Soo Park),윤경환(Gyeong-Hwan Yoon) 제어로봇시스템학회 2010 제어로봇시스템학회 각 지부별 자료집 Vol.2010 No.12

Underwater acoustic communication is a technique of sending and receiving messages below water. Currently, several kinds of communication methods have been developed for terrestrial environments. Especially, Dramatic advances in system designs of RF(Radio Frequency) communication have made possible the use of wireless modems for a variety of new monitoring and control applications. But, underwater communication is difficult due to factors like multi-path propagation, time variations of the channel, small available bandwidth and strong signal attenuation. Because of those reasons, RF signal is not suitable for underwater usages. And so underwater communication systems should be constituted with acoustic modems. This study aims to develop underwater communication systems using commercial acoustic module for lightweight Autonomous Underwater Vehicles(AUV), robot fishes and buoy platforms and so on. The structure of this study is as follows. First, we analyze the characteristics of the implementing underwater environments where basic specifications are presented. And then, selection process of the commercial acoustic communication module is presented. Finally, this paper evaluates the characteristics of selected modules in the coastal waters.

조발성 알쯔하이머병 환자에서 3년간 인지기능 및 행동 변화

오병훈(Byoung Hoon Oh),이창일(Chang Il Lee),남윤영(Yoon Young Nam) 대한노인정신의학회 2000 노인정신의학 Vol.4 No.1

Alzheimer's disease (AD) is the most typical progressive and irreversible dementia characterized by loss of intellectual capacity in many domains, altered behavior, inability to care for oneself, and ultimately neurologic abnormalities. In the treatment of AD, the focus is limited to relief of cognitive and behavioral symptoms. But the choice of adequate treatment according to severity level is difficult task for maintaining patient's quality of life. We experienced a case of typical presenile Alzheimer's disease who progressed severe dementia while being treated with cognitive enhancers and psychosocial intervention for three years. In review of this case, we conclude that early detection and active treatment of presenile dementia is most important factor for delaying of progress and decreasing of family burden.

논토양에서 자운영 환원이 인 유효도에 미치는 영향

박기도 ( Ki Do Park ),이창도 ( Chang Hoon Lee ),손일수 ( Il Soo Son ),박선태 ( Sun Tae Park ),안종웅 ( Jong Woong Ahn ),강위금 ( Ui Gum Kang ),박성태 ( Sung Tae Park ) 한국토양비료학회 2008 한국토양비료학회 학술발표회 Vol.2008 No.-

긍정적, 부정적 정서 자극에 의해 유발된 P3

안석균,이수정,남궁기,이창일,이은,김태훈,노규식,최혜원,박준모,An, Suk-Kyoon,Lee, Soo-Jung,NamKoong, Kee,Lee, Chang-Il,Lee, Eun,Kim, The-Hoon,Roh, Kyo-Sik,Choi, Hye-Won,Park, Jun-Mo 한국정신신체의학회 2001 정신신체의학 Vol.9 No.2

연구목적: 정상인에서 표정 자극에 의해 유발된 P3가 긍정적, 부정적 정서 범주에 따라 서로 다른지 여부를 알아보고자 하였다. 대상 및 방법: 정상인 12명을 대상으로 표정 사진에 의해 유발된 사건 관련 전위인 P3를 측정하였다. 모든 연구 대상에게 고빈도로 제시되는 비표적 바둑판 모양의 체크보드 자극으로부터 저빈도로 제시되는 표적 정서 자극에 대해 느끼고, 반응하도록 지시하였다. 결과: 정상인에서 부정적 정서 자극에 의해 유발된 P3의 진폭이 긍정적 자극에 의한 경우 보다 유의하게 더 컸다. 결론: 표정 자극에 의해 유발된 P3는 긍정적, 부정적 정서 처리의 정신생리적 지표로서 활용될 가능성이 시사된다. Objects : The aim of this study was to determine whether the P3 elicited by the negative emotional stimuli is different to that by positive stimuli. Methods : We measured the event-related potentials, especially P3 elicited by the facial photographs in 12 healthy subjects. Subjects were instructed to feel and respond to the rare target facial photographs imbedded in frequent non-target checkerboards. Results : We found that amplitude of P3 elicited by negative emotional photographs was significantly larger than that by the positive stimuli in healthy subjects. Conclusion : These findings suggest that P3 elicited by facial stimuli may be used as a psychophy-siological variable of the emotional processing.

환엽해당계 실생 검정법을 이용한 사과원 토양의 개식장해 발생가능성 진단

변재균(Byun Jae Kyun),이동훈(Lee Dong Hoon),권혜정(Kwon Hye Jung),이창은(Lee Chang Un) 한국원예학회 1999 Horticulture, Environment, and Biotechnology Vol.40 No.3

Geometry 정보와 오차 공분산을 이용한 협업 측위 오차 모델링

임정민(Jeong-Min Lim),오정훈(Jeong-Hun Oh),유상훈(Sang-Hoon Yoo),이창은(Chang-Eun Lee),성태경(Tae-Kyung Sung) 대한전기학회 2013 정보 및 제어 심포지엄 논문집 Vol.2013 No.10

Geometry 정보와 오차 공분산을 이용한 협업 측위 오차 모델링

임정민(Jeong-Min Lim),오정훈(Jeong-Hun Oh),유상훈(Sang-Hoon Yoo),이창은(Chang-Eun Lee),성태경(Tae-Kyung Sung) 대한전기학회 2013 대한전기학회 학술대회 논문집 Vol.2013 No.10

서울시 지하철 역사 출입구의 보행환경 개선방안

이창(Yi, Chang),이동훈(Lee, Dong-Hoon),이주아(Lee, Joo-Ah) 한국생태환경건축학회 2015 한국생태환경건축학회 논문집 Vol.15 No.4

보행환경 개선을 위한 지하철 역사 진,출입 시설 개편방향 연구

이창 ( Chang Yi ),이동훈 ( Dong Hoon Lee ),여혜진 ( Hae Jin Yeo ),이주아 ( Joo Ah Lee ) 서울시정개발연구원 2009 연구보고서 Vol.2009 No.57

Seoul`s subway is an important urban mass transportation system as it carries more than 4 million people for a day. It occupies 30% of transport modal share of Seoul citizens. To support this important mission, the outside entrance system of the subway was designed to maximize accessibility from the outside to the station buildings. However, the number and the layout of entrances were planned based on a uniform plan that the national government prepared for the entrance system of urban railways. Therefore, the entrances of the subway system of Seoul were planned without considering the unique characteristics of each station area. Applying the uniform national plan to all the subway stations raises problems as follow. First, some entrances can be inefficient in connecting the places where there are heavy volumes of potential subway users to the stations. Second, it is also possible that more than one entrances may be unnecessarily placed where accessibility is already sufficient. As a result, the entrances could encroach on limited space of sidewalk. Therefore, this study examines the current subway entrance system to identify its problems and attempts to propose a scheme for reorganizing entrances befitted with attributes of each station area and eventually improve pedestrian environment. . This study focuses on the No.2 subway line that passes the major centers of the city, and since a long time has passed after the completion of the subway system, buildings in the station areas adjacent to the subway entracnes are getting redevelopment pressure. Thus, when these areas are redeveloped, the proposals made in this study could be most useful. By conducting a field study and data analysis, this study identifies the following as the problems of the current entrance system of the subway in Seoul. First, the entrances encroach on pedestrian space that is already limited, and the stations on elevated highway create unpleasant pedestrian space; Second, some entrances could be inefficiently used and create monotonous cityscape; Third, a structure that connects the stations on elevated highway and the sidewalk has negative influence on walking environment such as creating dark space; Fourth, it is often the case that public establishments and residential districts located close to a station are not fully accessible from the subway through entrances. To provide solutions to the problems above, this study investigates all the entrances of the No.2 line and grouped them into certain types, intending to propose the reorganization scheme for each pattern. This study established three standards for the classification, which are the form of the station and the location of the entrances, and the width of adjacent roadways. These are important characteristics of the entrance itself and the areas surrounding the entrance that affect the reorganization schemes. Then, the authors, based on the analysis of the uses of buildings surrounding each entrance, proposed entrance reorganization plans for each type. This study finds that the entrances of underground stations located on 4 way intersections, that are formed by roadways more than 6 lanes, are adjacent to sizable commercial facilities and large office buildings. Also, high density residential districts are present near the entrance of this kind. For this type, we suggest installing the subway entrances inside the contiguous building. This proposal is most possible for this type since the buildings in such areas have relatively large floor space. As the road width becomes narrower, overall density decreased. For the type of the entrances that are located on the intersection formed by narrower roadways, we propose that two entrances could be combined into one so that removed entrance could free up large space for pedestrians. For the entrances located on mid-blocks, the study suggests that the entrances could be installed inside the adjacent building when large commercial or office buildings are nearby. When overall area is developed with low density, the city government is recommended to purchase a lot near the current entrance to install one vertical to the sidewalk so that sidewalk could be preserved for pedestrians. For the elevated stations, the authors propose installing a bridge connecting the stations and adjacent buildings, but this would be only possible when there are commercial or office facilities nearby with enough floor space. The study summarizes the pros and cons of each solution. Lastly, the study applied the proposed improvements on the Kyodae subway station entrances as a case study. It demonstrates how the proposed entrance reorganization schemes can be applied. In conclusion, we suggest the direction of the future study that can contribute to policymaking. First, to translate the proposal installing the entrance inside buildings into a reality, an incentive should be given to building or land owners. The future study should investigate which kinds of incentives exist and be effective in various situations. There are needs for research to examine potential problems that might arise during a negotiation process between the public and private sectors, assignment of cost for installing entrances, how and who to maintain entrances. Also, research studies should examine proper number of subway entrances for each station. It is important to draw up an accurate, but flexible standard for determining the number of entrances for the subway stations. This study is limited in that it only examines the entrances of the No.2 line subway stations. In the future, a research study investigating the whole line of the Seoul subway will be able to draw more persuasive policy recommendations.