대체 비상탈출 조건을 고려한 초음속 전투기용 캐노피 작동부 구조해석

김동현,김동만,김영우,양건명,Kim, Dong-Hyun,Kim, Dong-Man,Kim, Young-Woo,Yang, Jian-Ming 한국군사과학기술학회 2007 한국군사과학기술학회지 Vol.10 No.4

In this study, analysis of structural design criteria for the canopy actuating device has been conducted considering the aerodynamic breakaway capabilities of jettisonable canopy system. Unsteady aerodynamic loads for the opened canopy configuration at passively controlled jettision mode were computed using CFD method. The general purpose multi-body finite element code, SAMCEF Mecano, is used in the implemented analyses for the passive jettision condition. The recommended altitude and speed of aircraft was suggested as design criteria of aerodynamic breakaway capability of jettisonable canopy system as a bakup egress method when normal canopy jettison sequence malfunctioned. Aerodynamic breakaway condition of jettisonable canopy was also simulated and the fracture load conditions of canopy actuator were investigated.

하지길이 차이가 요통과 관절경직에 미치는 영향

김동현,김석범,백수정,남태호,김진상,Kim Dong-Hyun,Kim Suk-Bum,Baek Su-Jeong,Nam Tae-Ho,Kim Jin-Sang 대한물리치료학회 2002 대한물리치료학회지 Vol.14 No.4

Human body balances right and left leg centering around pelvis and spine. Therefore, imbalance of lower extremity means disequilibrium of the body. The difference of lower extremity length can cause a number of clinic symptoms including scoliosis, low back pain, sacroiliac pain, and sports injury. In this study, we tried to analyze low back pain and joint stiffness resulting from the difference of lower extremity length. The subjects were 80 male students who are 20-25 years old. The results of this study were as following: 1. Low back pain depending on the difference of lower extremity length One group which the difference of lower extremity length is above 12mm showed average different length as 18.0mm, the other group which one is below 12mm showed as 6.3mm. A group of above 12mm had more severe low back pain than a group of below 12mm. 2. Joint stiffness depending on the difference of lower extremity length A group of above 12mm had more severe joint stiffness than a group of below 12mm.

초등 과학영재 수업에서의 언어적 상호작용 사례 분석

김동현 ( Dong Hyun Kim ),김효남 ( Hyo Nam Kim ) 한국과학교육학회 2011 한국과학교육학회지 Vol.31 No.8

The purpose of this study was to analyze and extract the features of verbal interactions between teacher and science-gifted students in their classes. For the purpose of this study, authors observed 27 elementary science classes for the science gifted of three elementary teachers. To analyze the verbal interactions in the classes, the authors have adopted the theoretical background, which was based on Sinclair & Coulthard`s Initiative-Response- Feedback pattern. Verbal interactions in the classes were analyzed by Kim`s framework, which modified Jeong`s framework. IRF patterns were derived from the verbal interactions of science classes for the science gifted. As a result, authors obtained some important features in IRF pattern. The most commonly used IRF pattern was the teacher`s managerial question-student`s short answer pattern, which was due to the regional policy for the science gifted. The teacher`s delayed feedback as well as the teacher`s question was meaningful for student`s thinking ability. If elementary teachers consider the pattern, the strategy should be applied, which is depending on student levels and levels of contents. But three teachers did not show the characteristic verbal interaction regarded as a pattern strategy. In the future, inservice programs about verbal interaction are needed for the science gifted classes.

기업조직 내 소셜 미디어 서비스 활용의 가치 제고 및 활성화 방안

김동현,서현식,김형준,이봉규,Kim, Dong-Hyun,Seo, Hyun-Shik,Kim, Hyung-Joon,Lee, Bong-Gyou 한국정보처리학회 2011 정보처리학회논문지D Vol.18 No.4

본 연구의 목적은 조직 내 소셜 미디어를 활용하여 기업의 성과에 도움이 되는 방안을 찾고자 함에 있다. 최근 들어 기업들도 소셜 미디어를 다양한 분야에 활용하는 방안을 모색하고 있음에도 이에 대한 연구는 극히 미흡한 실정이다. 이에 본 연구는 소셜 미디어 서비스 사용자 간의 커뮤니케이션이 증가하게 되면 다양한 인간관계 형성 및 확장이 발생되고, 이것은 다시 정보공유, 자아추구, 사회참여, 유희(오락) 등의 성과로 이어지는 연구모형을 설정하였다. 연구의 효과를 극대화하기위해 연구대상을 소셜 미디어 서비스를 이용하는 직장인과 비직장인들로 분류하여 조사 및 분석하였다. 연구 결과, 직장인들은 모르는 사람들과 지식을 공유한 후, 습득된 지식을 바탕으로 자신의 이미지를 지인들에게 어필하는 것으로 나타났다. 또한, 소셜 미디어 기능에 유희(오락)성을 포함시키면 조직 내 소셜 미디어의 사용이 활성화되어 경영참여로 이어질 수 있는 것으로 분석되었다. 본 연구는 향후 조직 내 소셜 미디어 서비스를 활용할 경우 유용한 가이드라인으로 사용될 수 있을 것이다. The purpose of this study is to find the beneficial plan for business success by the advantage of social media service in the business organization. There is few research for applying social media on a variety of fields in business organization although many companies are trying to find the way for its application. Hence, this study identifies the possibility for the utilization of social media services, and it also finds the plan for their effective application. The social relationship is created by increasing communications between users of social media service. The research model is established on the basis of the hypothesis that the social relationship affects knowledge share, pursuit of ego, social participation, amusement. To maximize the impact of results, the research was conducted on the basis of the target on two groups including the business men and non-business men who use social media services. As results of the research, the business men tend to appeal their impression based on sharing knowledge with anonymous people. Also, it is necessary to make a social participation to a management participation, and to utilize the social media in the organization by including amusement to its function. This research is expected to have significant implication to companies which wants to apply social media services in the future.

느타리 버섯류 ( Pleurotus spp. ) 의 생화학적 방법에 의한 품종구분

김동현,공원식,김경수,김영호,유창현,김영배 ( Dong Hyun Kim,Won Sik Kong,Kyung Soo Kim,Young Ho Kim,Chang Hyun You,Young Bae Kim ) 한국균학회 1998 韓國菌學會誌 Vol.26 No.2

김연아 선수의 ``값진 준우승``: 2011세계피겨선수권대회 관련 보도의 서사구조와 이데올로기

김동현 ( Dong Hyun Kim ) 한국스포츠정책과학원(구 한국스포츠개발원) 2012 체육과학연구 Vol.23 No.1

This study looks into the narrative structure of newspaper media on ``precious winning of the second prize`` of Yuna Kim in the World Figure Championships 2011 and analyzes the socio-cultural ideology representation in it. Also, from the way how the media describe the sports celebrity, the study attempted to read the unique cultural pattern of medias to conserve the fame and marketability of sports celebrity, For the analysis, this study selected 82 news articles from 5 different newspapers right before and after the world Figure championships 2011, and derived the conclusion by using narrative analysis method. The narrative structure is divided into four states: ``waiting for return of queen``, ``the figure queen returns``, ``precious winning of the second prize`` and ``retake of crown through figure`` In each state, medias, in accordance with the narration through a reflection of her successful discourse on national identity, through the identification with the nation, through the nationalism sentiment, through her unconditional patriotism, actively gave an effort to maintain the fame and marketability of Yuna Kim. The chief topic of this research, Korean Figure Skater Kim Yuna`s ``precious winning of the second prize``, is resulted from the integration of her unconditional patriotism grounded on nationalism having an inseparable relationship with sports. 이 연구에서는 2011세계피겨선수권대회 김연아 선수의 ``값진 준우승``을 둘러싼 신문기사의 서사구조와 그 안에서 재현되는 사회적 가치체계 분석을 통해 미디어가 스포츠 명사를 묘사하는 방식을 살펴보고, 필요에 따라 스포츠 명사들의 유명세 및 상품성을 보존하고자 하는 미디어의 전개방식과 특징적인 문화적 패턴을 읽어 내고자 하였다. 이를 위해 5개의 신문사 가운데, 2011세계피겨선수권대회 전과 후에 김연아 선수와 관련된 82개의 신문기사를 분석대상으로 사용하였으며, 서사분석법을 이용하여 결론을 도출하였다. 서사구조는 ``여왕의 귀환을 기다림``, ``돌아온 피겨여왕``, ``값진 준우승``, ``피겨를 통한 여왕으로 재등극``의 네 가지 국면으로 분석하였으며, 각 국면에서의 미디어는 서사의 흐름에 따라, 때로는 그녀의 성공적 담론에 국가정체성을 중첩시키려는 시도를 통해, 때로는 국가와의 동일시를 통해, 때로는 민족주의적 정서를 통해, 때로는 그녀의 맹목적 애국심을 통해 그녀의 유명세 및 상품성을 유지하는데 적극적으로 작용하고 있음을 보여준다. 마지막으로 이 연구의 주요논제인 김연아 선수의 ``값진 준우승``은 스포츠와 불가분의 관계를 유지하고 있는 민족주의를 기반으로 한 그녀의 맹목적 애국심이 융합되어 나타난 결과라고 할 수 있다.

식용 식물자원으로부터 활성물질의 탐색 -XIII. 개망초(Erigeron annuus L.) 꽃으로부터 triterpenoid의 분리-

김동현,정성제,방명호,정인식,김성훈,권병목,김대근,박미현,백남인,Kim, Dong-Hyun,Jung, Sung-Je,Bang, Myun-Ho,Chung, In-Sik,Kim, Sung-Hoon,Kwon, Byoung-Mog,Kim, Dae-Keun,Park, Mi-Hyun,Baek, Nam-In 한국응용생명화학회 2004 Applied Biological Chemistry (Appl Biol Chem) Vol.47 No.4

개망초의 꽃을 80% MeOH 용액으로 추출하고, 추출물을 EtOAc, n-BuOH 및 물로 분배, 추출하였다. 이 중 EtOAc 분획을 silica gel, octadecylsilica gel(ODS) column chromatography 및 high performance liquid chromatography(HPLC)로 정제하여 3종의 화합물을 분리하였다. 각 화합물의 화학구조는 NMR, MS 및 IR 등의 스펙트럼 데이터를 해석하여, ${\alpha}-amyrenone(1),\;{\alpha}-amyrin(2)$ 및 ${\beta}-amyrin(3)$으로 동정하였다. 이들 3종의 triterpenoid는 개망초에서는 처음 분리되었다. The flower of Erigeron annuus L. was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, three compounds were isolated through the repeated silica gel, ODS column and high performance liquid chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\alpha}-amyrenone,\;{\alpha}-amyrin\;and\;{\beta}-amyrin$. These three compounds were isolated for the first time from the flower of Erigeron annuus L.

ICT 기반의 인삼 공정 육묘 시 질소 형태와 게르마늄(Ge) 유무가 생장에 미치는 영향

김동현,김연복,구현정,백현진,이수빈,최지혜,홍의기,장광진,Dong Hyun, Kim,Yeon Bok, Kim,Hyun Jung, Koo,Hyun Jin, Baek,Su Bin, Lee,Jeei Hye, Choi,Eui Gi, Hong,Kwang Jin, Chang 국립한국농수산대학교 교육개발센터 2022 현장농업연구지 = Journal of practical agricultural resear Vol.24 No.4

Ginseng hydroponic cultivation was cultivated as a nutrient solution and the growth was investigated 60 days later. The length(cm) increased from EC1.0 and EC2.0 concentrations to 5.47cm before, followed by EC0.5, 2.5, 1.5, and 0.0. The weight(g) increased from EC1.0 concentration to 2.39g before, followed by EC1.5, 2.5, 0.5, 0.0 and 2.0. The width(mm) increased from EC1.0 concentration to 1.9mm than before, followed by EC2.5, 0.5, 1.5, 2.0, and 0.0. In the ginseng growth experiment according to nutritional components, the average length of NO₃-N mixed experiment increased to 0.33cm, the average weight of 0.04g, and the average width of 0.35mm. In the experiment in which NH₄-N was mixed without NO₃-N, the growth was reduced to 0.37cm in average length, 0.03g in average weight, and 0.22mm in average width. In an experiment in which germanium(Ge) is mixed with a nutrient component, the average length is increased to 0.33cm, the average weight is increased to 0.04g, and the average width is increased to 0.35mm, but in an experiment excluding germanium(Ge), the growth is reduced to 0.11cm, the average weight is 0.04g, and the average width is 0.03mm.

슬러지 폐기물을 활용한 반도체급 균일한 콜로이달 실리카 나노입자의 제조 및 CMP 응용

김동현,김지원,제갈석,김민정,김하영,김민상,김상춘,박선영,윤창민,Kim, Dong Hyun,Kim, Jiwon,Jekal, Suk,Kim, Min Jeong,Kim, Ha-Yeong,Kim, Min Sang,Kim, Sang-Chun,Park, Seon-Young,Yoon, Chang-Min 유기성자원학회 2022 유기물자원화 Vol.30 No.3

This study suggests the effective recycling method of sludge waste from various industrial fields to synthesize uniform colloidal silica nanoparticles. In detail, polymers are removed from the sludge waste to attain sludge-extracted silica (s-SiO₂) micron-sized particles, and ammonia assisted sonication is applied to s-SiO₂, which has effectively extracted the silanol precursor. The nano-sized silica (n-SiO₂) particles are successfully synthesized by a typical sol-gel method using silanol precursor. Also, the yield amounts of n-SiO₂ are determined by the function of s-SiO₂ etching time. Finally, n-SiO₂-based slurry is synthesized for the practical CMP application. As a result, rough-surfaced semiconductor chip is successfully polished by the n-SiO₂-based slurry to exhibit the mirror-like clean surface. In this regard, sludge wastes are successfully prepared as valuable semicondutor grade materials.

간 질환력과 원발성 간암에 관한 환자-대조군 연구

김동현,박병주,유근영,안윤옥,이효석,김정룡,이상일,이무송,안형식,김헌,박태수,Kim, Dong-Hyun,Park, Byung-Joo,Yoo, Keun-Young,Ahn, Yoon-Ok,Lee, Hyo-Suk,Kim, Chung-Yong,Lee, Sang-Il,Lee, Moo-Song,Ahn, Hyung-Sik,Kim, Heon,Park, Tae-Soo 대한예방의학회 1994 Journal of Preventive Medicine and Public Health Vol.27 No.2

The relationship between past liver disease history and the risk of primary liver cancer was analyzed in a hospital-based case-control study conducted in Seoul on 165 patients with histologically or serologically confirmed hepatocellular carcinoma and individually age- and sex-matched 165 controls in hospital for ophthalmologic, otologic, or nasopharyngeal problems. Significant association were observed for liver deseases occurring 5 or more years before liver cancer diagnosis [OR,4.9;95% confidence interval (CI), $1.6{\sim}14.0$) and family history of liver disease(OR, 9.0;95% CI, $2.1{\sim}38.8$). These associations were not appreciably modified by allowance for major identified potential confounding factors. From these results, it is possible to speculate that liver cell injuries caused by various factors might be a common pathway to developing primary liver carcinoma. Considering the significant effect of family history of liver diseases on PLCA risk after adjusting past liver disease history, there might be genetic susceptibility in the carcinogenic mechanism of liver cancer. Further investigations are needed to clarify the effect of family history of liver disease on PLCA risk.