• 제목/요약/키워드: Boundary representation

검색결과 211건 처리시간 0.028초

Stability of suspension bridge catwalks under a wind load

  • Zheng, Shixiong;Liao, Haili;Li, Yongle
    • Wind and Structures
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    • 제10권4호
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    • pp.367-382
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    • 2007
  • A nonlinear numerical method was developed to assess the stability of suspension bridge catwalks under a wind load. A section model wind tunnel test was used to obtain a catwalk's aerostatic coefficients, from which the displacement-dependent wind loads were subsequently derived. The stability of a suspension bridge catwalk was analyzed on the basis of the geometric nonlinear behavior of the structure. In addition, a full model test was conducted on the catwalk, which spanned 960 m. A comparison of the displacement values between the test and the numerical simulation shows that a numerical method based on a section model test can be used to effectively and accurately evaluate the stability of a catwalk. A case study features the stability of the catwalk of the Runyang Yangtze suspension bridge, the main span of which is 1490 m. Wind can generally attack the structure from any direction. Whenever the wind comes at a yaw angle, there are six wind load components that act on the catwalk. If the yaw angle is equal to zero, the wind is normal to the catwalk (called normal wind) and the six load components are reduced to three components. Three aerostatic coefficients of the catwalk can be obtained through a section model test with traditional test equipment. However, six aerostatic coefficients of the catwalk must be acquired with the aid of special section model test equipment. A nonlinear numerical method was used study the stability of a catwalk under a yaw wind, while taking into account the six components of the displacement-dependent wind load and the geometric nonlinearity of the catwalk. The results show that when wind attacks with a slight yaw angle, the critical velocity that induces static instability of the catwalk may be lower than the critical velocity of normal wind. However, as the yaw angle of the wind becomes larger, the critical velocity increases. In the atmospheric boundary layer, the wind is turbulent and the velocity history is a random time history. The effects of turbulent wind on the stability of a catwalk are also assessed. The wind velocity fields are regarded as stationary Gaussian stochastic processes, which can be simulated by a spectral representation method. A nonlinear finite-element model set forepart and the Newmark integration method was used to calculate the wind-induced buffeting responses. The results confirm that the turbulent character of wind has little influence on the stability of the catwalk.

조르주 슈비츠게벨의 "회화의 주체" 작품연구 - 들뢰즈의 감각이론과 프레임이론을 중심으로 - (Research on Georges Schwizgebel's "The Subject of Picture" - Focus on Deleuze's Frame Theory and Sensibility Theory -)

  • 정동희;김재웅
    • 한국콘텐츠학회논문지
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    • 제7권5호
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    • pp.102-109
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    • 2007
  • 회화에서 프레임의 미학을 연구하는 것보다 애니메이션 화면구성에 대한 프레임을 분석하는 것은 더욱 더 중요한 의미를 지니고 있다. 단편 애니메이션작가 조르주 슈피츠게벨의 이미지 형상은 캐릭터를 지우는 흔적을 통하여 작가 신체의 촉각적 감각으로 형상화된 구체적인 표현이라고 말할 수 있다. 이는 들뢰즈가 언급한 형상지우기에 의한 흔적의 변형(메타모포시스 Metamorphosis)과 비유된다. 애니메이션에서 살아 숨쉬는 캐릭터는 들뢰즈가 기술한 형상과 같이 실사영상과는 구별된다. 애니메이션은 프레임 안에서 움직이는 캐릭터의 형상과 큰 움직임이 없는 배경으로 나눠질 수 있는데, 움직이지 않는 배경의 구성은 들뢰즈가 언급한 아플라와 유사한 성격을 갖는다. 이는 실사영상을 프레임 단위로 기록하는 영화와는 다르게 애니메이션은 실제와는 다른 경계인 아플라를 배경으로 표현하고 있으며, 캐릭터는 최소한의 구상성을 갖고 대상에 대한 형상의 일그러짐을 통하여 새로운 형상으로 재탄생되고 있다. 다음은 프레임의 시간지속에 대한 문제이다. 슈피츠게벨의 작품은 프레임과 프레임사이의 상관관계에 의하여 의미가 생성된다. 그의 작품에서는 프레임과 프레임 간의 구성에 따른 형상 묘사 자체가 프레임으로 구성된다. 이러한 과정을 통하여 슈비츠게벨의 작품은 각 프레임 사이에 연결되어 있는 개별 프레임이 새롭게 생성되는 대상의 형상을 묘사하고 있다. 이는 대상에 대한 지시체의 근본이 적용되지 않는 현대영화에서 극히 적게 찾아 볼 수 있다고 들뢰즈는 언급한다. 바꿔 말하면 슈비츠게벨의 작품은 현대영화의 특징을 갖춘 애니메이션으로 프레임과 프레임 사이의 형상을 묘사하고 있다. 이는 들뢰즈가 언급한 대상세계의 법칙과 논리에서 벗어나 이루어지는 크리스털적 묘사임을 알 수 있다.

분할격자체계를 이용한 천수흐름 수치모형의 개발 (Development of a Numerical Model of Shallow-Water Flow using Cut-cell System)

  • 김형준;이승오;조용식
    • 한국방재학회 논문집
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    • 제8권4호
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    • pp.91-100
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    • 2008
  • 본 연구는 Cartesian 격자망을 기본으로 하여 복잡한 지형을 위한 격자를 간편하고 효율적으로 생성할 수 있는 기법인 분할격자체계를 제안하고자 한다. 분할격자기법은 전반적인 흐름영역의 격자는 균일한 크기의 Cartesian 격자로 표현하지만 수치모형의 정확성, 적용성 및 효율성을 증대시키기 위하여 흐름의 특성이 변하는 격자를 분할하여 처리하는 기법이다. 분할격자체계에 의한 격자망은 다양한 크기 및 형상을 지니게 되므로, 유한체적기법을 적용하여 복잡한 흐름영역을 위한 수치모형을 구성한다. HLLC Riemann 근사해법을 이용하여 지배방정식을 이산화하였으며, 수치해의 안정성을 기하기 위하여 TVD-WAF기법을 적용하였다. 분할격자체계를 이용한 수치모형을 검증하기 위하여 해석해가 존재하는 사각형수조의 자유진동흐름을 모의하였다. 해석해와 수치모의 결과를 비교하여 본 연구에서 제안된 기법이 균일격자 및 분할격자체계에서 자유수면변위 및 x-축 및 y-축 방향의 유속을 정확히 모의함을 확인하였다.

Web GIS를 이용한 수요자 중심의 하천수질 정보시스템 구현 (Development of a user-friendly information system for river water quality using Web GIS)

  • 엄정섭;신소은
    • Spatial Information Research
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    • 제10권1호
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    • pp.45-59
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    • 2002
  • 정부에서 국민에게 공개하는 하천수질정보가 비환경전문가인 일반 수요자의 지식 수준을 고려한 서비스를 제공하지 못하는 한계가 있다. 이와 간은 문제에 대해 대안 을 제시하고자, 본 연구에서는 수직오염 측정결과와 지역주인이 일상생활에서 접하고 있는 지역의 지도(행정경계, 수계, 도로망등)를 결합하여 2차일 수질오염지도를 제작 하였다. 다양한 수질폭정항목에 대해 다년간 축척된 방대한 자료를 간단하게 검색하 고 컴퓨터 지도에 출력할 수 있는 인터페이스가 설계되었다. 아울러 수질측정결과를 그래픽정보로 가공하여 광역적인 수직오염변화 추이를 풍부한 시각 정보로 지도상에 디스플레이 할 수 있는 기법이 구현되었다. 본 연구를 통하여 구축된 시스템은 인터 넷의 편리한 인터페이스, 자로 공유의 편리성을 이용하여 전 세계 어디에서나 서비스 에 대한 접근이 가능하다. 본 수요자 중심의 대민수질환경 인터넷GIS가 정부차원에서 도입되어 실무에 이용될 경우, 일반인이 수질환경에 내한 전문지식을 습득할 필요없 이, 검색하고자 하는 지역과 각종 수질측정 데이타를 선택하여 실생활과 관련된 수질 정보에 접근할 수 있어, 대민 환경정보 서비스 질의 개선측면에서 획기적인 계기를 마련할 것으로 사료된다.

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종단 간 심층 신경망을 이용한 한국어 문장 자동 띄어쓰기 (Automatic Word Spacing of the Korean Sentences by Using End-to-End Deep Neural Network)

  • 이현영;강승식
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제8권11호
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    • pp.441-448
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    • 2019
  • 기존의 자동 띄어쓰기 연구는 n-gram 기반의 통계적인 기법을 이용하거나 형태소 분석기를 이용하여 어절 경계면에 공백을 삽입하는 방법으로 띄어쓰기 오류를 수정한다. 본 논문에서는 심층 신경망을 이용한 종단 간(end-to-end) 한국어 문장 자동 띄어쓰기 시스템을 제안한다. 자동 띄어쓰기 문제를 어절 단위가 아닌 음절 단위 태그 분류 문제로 정의하고 음절 unigram 임베딩과 양방향 LSTM Encoder로 문장 음절간의 양방향 의존 관계 정보를 고정된 길이의 문맥 자질 벡터로 연속적인 벡터 공간에 표현한다. 그리고 새로이 표현한 문맥 자질 벡터를 자동 띄어쓰기 태그(B 또는 I)로 분류한 후 B 태그 앞에 공백을 삽입하는 방법으로 한국어 문장의 자동 띄어쓰기를 수행하였다. 자동 띄어쓰기 태그 분류를 위해 전방향 신경망, 신경망 언어 모델, 그리고 선형 체인 CRF의 세 가지 방법의 분류 망에 따라 세 가지 심층 신경망 모델을 구성하고 종단 간 한국어 자동 띄어쓰기 시스템의 성능을 비교하였다. 세 가지 심층 신경망 모델에서 분류 망으로 선형체인 CRF를 이용한 심층 신경망 모델이 더 우수함을 보였다. 학습 및 테스트 말뭉치로는 최근에 구축된 대용량 한국어 원시 말뭉치로 KCC150을 사용하였다.

스웨덴의 시간제근로: 유연성과 성평등의 긴장 속 공존 (Part-time Work in Sweden: The Coexistence in Tension of Flexibility and Gender Equality)

  • 김영미
    • 산업노동연구
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    • 제17권1호
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    • pp.297-323
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    • 2011
  • 스웨덴 시간제근로가 주로 여성들의 일자리로 자리잡고 있음에도 불구하고 주변화되지 않고 좋은 일자리로 자리잡게 된 데에는 다음 세가지 조건이 가장 중요하였다고 판단된다. 첫째, 스웨덴에서 시간제근로는 고용유연화를 목적으로 한 것이라기 보다는 생계부양자 모형의 전환을 목적으로 한 포괄적인 일-생활 양립 프로젝트의 일환으로 확산되었으며 보육정책, 육아휴직정책과 긴밀하게 연계되어 시행되고 있다는 점이다. 둘째, 단시간근로 청구권을 바탕으로 한 전환형 시간제가 많아 종사상 지위의 측면에서 볼 때 전일제와 시간제의 지위 상 경계의 구분이 쉽지 않고 부가급여, 사회급여에서 차별적 대우의 근거가 없다는 점이다. 세째 EU근로시간 지침과 노동법, 단체협약에 의해 전일제근로의 노동시간에 대한 규제가 엄격하게 이루어지고 있어 시간제근로에 대한 수요가 크고 그와 함께 시간제근로의 초과근무를 엄격하게 통제하고 있어 시간제근로가 실질적으로 안착될 수 있었다는 점이다. 시간제근로가 스웨덴 여성들의 경제활동 및 생애과정에 미친 영향과 관련해서는 시간제근로가 여성 고용률을 증가시키는 데 기여했다는 데는 연구자들 간에 큰 이견이 없다. 1970년대 이후 시간제근로의 확산 과정을 보면 시간제근로는 기존에 경제활동을 하고 있던 전일제 여성근로자들을 시간제로 전환시킨 것보다는 경제적으로 비활동적이었던 여성들을 노동시장으로 끌어들인 효과가 훨씬 컸다. 시간제근로 확산 이후 스웨덴 여성들의 생애과정의 지배적인 패턴은 양육기 이전 전일제-양육기 시간제-양육기 이후 전일제로 양육기의 경력단절이 최소화된 패턴으로 대체된 것으로 평가된다. 성평등의 관점에서 볼 때 스웨덴의 시간제근로는 여성화의 문제, 여전히 온존하고 있는 성별직종분리의 문제 등 분리된 일자리라는 한계를 안고 있음에도 불구하고 여성들의 노동시장 통합도를 높이고 전일제로의 징검다리 역할을 하는 긍정성을 보여주고 있다.

전통공간 재현을 위한 광한루원의 수목정비방안 연구 (A Study on the Maintenance Plan of Trees in Gwanghalluwon Garden for Representing Traditional Space)

  • 이원호;김동현;김재웅;안혜인;김대열;조운연
    • 한국전통조경학회지
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    • 제32권3호
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    • pp.82-95
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    • 2014
  • 본 연구는 전통공간의 수목정비방안 마련을 위해 광한루원을 사례로 진행되었다. 이를 위해 전통공간의 수종 선정과 수목정비 동향에 대한 이론적 고찰이 선행되었으며, 광한루원의 현장조사를 통한 식재현황을 분석하고, 과거 문헌 및 기록 등에 나타나는 수종 및 식재경관을 토대로 광한루원의 수목정비방안을 도출한 결과는 다음과 같다. 첫째, 전통공간의 수종 선정과 수목정비에 관한 동향을 살펴본 결과, 전통공간 내에 식재된 외래수종에 대하여 맹목적인 지양은 한계가 있으며 전통공간의 수종 선정에 대한 논의는 오늘날까지 이어져오고 있는 시점에서 수목정비에 대한 외래수종의 무분별한 제거 및 향토식물의 맹목적 식재 등의 이분법적 정비방안 및 비검증된 사료의 맹신은 배제되어야 한다. 둘째, 광한루원 내에 식재된 수종을 조사한 결과 소나무, 느티나무, 은행나무, 배롱나무 등 전통공간에서 애용되었던 수종들이 주로 식재되어 있으나 각 공간의 성격을 고려할 때, 광한루 일대를 제외한 광한루원 경내의 수목 식재는 전통공간의 성격과는 무관한 것으로 판단된다. 셋째, 문헌이나 문학작품 등에서 나타나는 광한루원의 수목식재 관련 기록을 살펴본 결과, 현재 광한루원 내에 식재된 수종 중 버드나무류, 배롱나무, 대나무(이대), 연꽃만이 나타나고 있어 고증을 통한 수목정비에는 무리가 따른다. 넷째, 광한루원의 각 권역별 수목정비방안을 모색한 결과, 광한루 권역은 역사적 시대성과 장소성을 지니고 있으며 오늘날 그 모습을 복원해나가고 있어 현재의 상태를 유지하는 방향으로 설정되어야 한다. 완월정 권역은 광한루의 건조물군과 유사한 형태로서 자칫 원형으로 오인될 수 있으므로 완충식재를 통한 전이 공간 조성 등 광한루 권역과는 다른 별도의 장소성 확보가 필요하다. 월매집 권역과 잔디광장 권역은 과거 성외 장시이자 대규모의 숲으로서 율림의 상징적 복원과 동시에 경내의 편의시설 및 관리시설의 집적을 통해 성외 장시의 모습을 재현하도록 하며, 완월정 동측 잔디광장은 완월정 권역과 연계하여 활용적 측면에서 현재와 같이 개방된 형태를 유지하는 방안을 제언하고자 한다. 광한루원 경계 권역은 고증의 측면과 현존요소의 진정성 여부를 살펴보았을 때 전통공간의 장소성과는 연관 짓기 어려운 장소로서 과거 문학작품에서 나타나는 문화경관을 반영하는 것 또한 하나의 정비방안으로 고려할 만하다 판단된다.

멜로드라마 속의 사로잡힌 정동(Captive Affects), 탄력적 고통(Elastic Sufferings), 대리적 대상(Vicarious Objects) -어구스틴 잘조사의 멜로드라마 재고 (Captive Affects, Elastic Sufferings, Vicarious Objects in Melodrama -Refiguring Melodrama by Agustin Zarzosa)

  • 안민화
    • 대중서사연구
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    • 제25권1호
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    • pp.429-462
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    • 2019
  • 본고는 어구스틴 잘조사(Agustin Zarosa)의 2013년 저작, 『영화와 텔레비전 멜로드라마 재고하기: 사로잡힌 정동, 탄력적 고통, 대리적 대상』(Refiguring Melodrama in Film and Television: Captive Affects, Elastic Sufferings, Vicarious Objects)을 통해, 기존의 멜로드라마의 핵심 개념들로 다루어져 왔던 모드, 정동, 고통(히스테리아), 과잉에 대한 논의들을 계보학적으로 다시 논의하며, 동시대 새로운 화두로 떠오른, 정동이론과 환경, 동물등과 포스트 휴머니즘 담론이 어떻게 멜로드라마 개념에 접목될 수 있는 지 논한다. 1장에서는, 모드를, 선과 악이 한 쌍이 되는 매커니즘 안에서, 사회 전체를 가로지르는 고통의 시각성을 재분배하는 장치로서의 멜로드라마의 개념으로 넓히며, 선과 악의 구별을 증명하기 위한 수단으로써 고통을 드러내는 멜로드라마의 모드에 대한 브룩스의 논의를 반박한다. 2장은 들뢰즈식 형이상학의 관점으로부터 멜로드라마가 의미의 체계라기보다는 '특정화'(sepcification)의 탄력적 시스템임을 논한다. <언덕위의 집>(빈센트 미넬리)의 분석을 통해, 신체들간의 조우를 통해 생성된 정동과 -의미가 아닌-정동이 흐르는 장소로써의 미장센에 주목한다. 3장은 브룩스의 붕괴된 도덕적 질서를 회복시키는 멜로드라마의 역할에 대한 논의에 반대하며, 멜로드라마는 미해결로 남아 있는 (여성) 고통에 대한 인지 혹은 시각화를 위해 존재한다고 강조한다. <세이프>(토드 헤인즈)는 환경으로 인한 여성 고통을 다루면서 기존의 여성 히스테리와 멜로드라마라는 논의에 생태비평주의적 관점을 더한다. 나머지 두 챕터들은 동물과 포스트휴먼 멜로드라마를 논의함으로써, 인간의 명제를 제한하고 확장하는 데 있어서의 멜로드라마의 역할을 연구한다. 희생과 과잉이라는 멜로드라마의 명제가 어떻게 -인간중심적인-인간과 비인간의 경계를 흐리게 하는 지 분석한다. 잘조사는 피터 브룩스의 논의에서 도출된 모드, 정동, 고통의 개념들을 일부분 받아들이면서도, 각각 들뢰즈주의, 페미니즘, 포스트휴머니즘(캐리 울프, 아키라 리핏)의 논의들을 부가하며, 브룩스의 정전화된 멜로드라마의 개념에 도전하고 있다.

1970년대 한국 영화와 타자들의 풍경 -'가족'과 '죽음' 모티프를 중심으로 (1970s Korean film and landscape of Others -with 'family community' and 'death' motif)

  • 한영현
    • 대중서사연구
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    • 제25권4호
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    • pp.429-465
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    • 2019
  • 이 글은 1970년대 한국 영화에 재현된 타자들의 존재 방식에 대해 분석했다. 당대의 사회 변화들, 가령 급속한 산업 근대화로 인한 도시화 속에서 수많은 사람들이 근대화의 열매를 얻기 위해 산업 역군으로서의 주체 구성을 해 나갔지만, 이러한 주체 구성의 과정에서 필연적으로 양산되었던 타자들의 풍경은 그동안 젠더 및 청년 담론 속에서 제한적으로 분석되어 왔다. 이러한 점에 착안하여 이 글은 시각을 달리하여 1970년대적 타자들의 풍경을 추출해내는 데 목적을 두었다. 타자들의 존재 방식은 다음의 두 가지 구분 속에서 발견할 수 있다. 첫째, 1970년대 영화에서 가족 공동체는 1960년대의 그것과는 달리 해체되고 균열된 상태로 존재하는데, 이는 타자들이 그 공동체에 진입할 수 없거나 이탈함으로써 발생한다. 가족 공동체는 더 이상 주체 구성의 안정된 토대 혹은 구심점으로 작용하지 못하는데, 안정감과 소속감을 가질 수 없다는 공동체에 대한 절망적 인식은 공동체 안팎을 배회하는 타자들의 존재 방식을 통해 잘 드러난다. 둘째, '죽음'은 1970년대 국가 이데올로기의 폭력과 일상화된 예외 상태 속에서 사회적 삶의 한 양태를 보여 주는 요소이다. 국가가 요청한 정상적 주체성에서 완벽하게 배제되고 추방된 타자들이 영화 안에서 죽는 방식은 일상화된 죽음 혹은 잠재적 죽음의 상태가 1970년대의 삶이라는 점을 보여 준다. 급격한 도시화와 산업화를 통해 추구된 정상적 삶은 타자화된 존재들을 죽음에 이르도록 하지만, 실제 타자들의 존재 방식은 안정감과 소속감을 부여하는 국가의 경계를 무너뜨리고 삶과 죽음의 경계가 무색해진 1970년대 절망적 현실을 고발하는 것이다. 결과적으로 1970년대 타자들의 풍경은 1970년대 산업 근대화가 그토록 지향했던 완벽한 중산층 가족 담론을 파괴하고 그것이 오히려 수많은 죽음을 초래하는 타자들을 양산하는 폭력적 현실을 드러낸다. 한국영화는 정권의 검열에도 불구하고, 재현의 우회로를 따라 1970년대가 가져온 삶의 폭력성을 대중적으로 폭로하고 있었던 것이다.

Sensory Information Processing

  • Yoshimoto, Chiyoshi
    • 대한의용생체공학회:의공학회지
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    • 제6권2호
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    • pp.1-8
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    • 1985
  • The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70$\pm$1.32mmHg/min)compared to CF dialyzers(4.32$\pm$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers. 30527 T00401030527 ^x For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500, 550, 570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500, 550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm. 30535 T00401030535 ^x Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided into two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weight). The other group received no Photofrin II. Mice from both groups were irradialed for approximately 15 minutes at 100, 300, or 500 mW/cm2 with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photolfrin II increased surface temperature by at least 40% and the temperature rise due to 300 mW/cm2 irradiation exceeded values for hyperthermia. Light and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise. 30536 T00401030536 ^x We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies. 30537 T00401030537 ^x It is well known that nonlinear propagation characteristics of the wave in the tissue may give very useful information for the medical diagnoisis. In this paper, a new method to detect nonlinear propagation characteristics of the internal vibration in the tissue for the low frequency mechanical vibration by using bispectral analysis is proposed. In the method, low frequency vibration of f0( = 100Hz) is applied on the surface of the object, and the waveform of the internal vibration x (t) is measured from Doppler frequency modulation of silmultaneously transmitted probing ultrasonic waves. Then, the bispectra of the signal x (t) at the frequencies (f0, f0) and (f0, 2f0) are calculated to estimate the nonlinear propagation characteristics as their magnitude ratio, w here since bispectrum is free from the gaussian additive noise we can get the value with high S/N. Basic experimental system is constructed by using 3.0 MHz probing ultrasonic waves and the several experiments are carried out for some phantoms. Results show the superiority of the proposed method to the conventional method using power spectrum and also its usefulness for the tissue characterization. 30541 T00401030541 ^x This paper describes the implementation of a computerized radial pulse diagnosis by aids of a clinical expert. On this base, we composed of the radial pulse diagnosis system in korean traditional medicine. The system composed of a radial pulse wave detection system and a radial pulse diagnosis system. With a detection system, we detected Inyoung and Cheongu radial pulse wave and processed it. Then, we have got the characteristic parameters of radial pulse wave and also quantified that according to the method of Inyoung-Cheongu Comparison Radial Pulse Diagnosis. We defined the jugement standard of radial pulse diagnosis system and then we confirmed the possibility for realization of automatic radial pulse diagnosis in korean traditional medicine. 30545 T00401030545 ^x Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined. 30575 T00401030575 ^x A medical image workstation was developed using multimedia technique. The system based on PC-486DX was designed to acquire medical images produced by medical imaging instruments and related audio information, that is, doctors' reporting results. Input information was processed and analyzed, then the results were presented in the form of graph and animation. All the informations of the system were hierarchically related with the image as the apex. Processing and analysis algorithms were implemented so that the diagnostic accuracy could be improved. The diagnosed information can be transferred for patient diagnosis through LAN(local area network). 30592 T00401030592 ^x In the conventional infrared imaging system, complex infrared lens systems are usually used for directing collimated narrow infrared beams into the high speed 2-dimensional optic scanner. In this paper, a simple reflective infrared optic system with a 2-dimensional optic scanner is proposed for the realization of medical infrared thermography system. It has been experimentally proven that the intfrared thermography system composed of the proposed optic system has the temperature resolution of 0.1˚c under the spatial resolution of lmrad, the image matrix size of 256 X 240, and tile imaging time of 4 seconds. 30593 T00401030593 ^x In this paper, MIIS (Medical Image Information System) has been designed and implemented using INGRES RDBMS, which is based on a client/server architecture. The implemented system allows users to register and retrieve patient information, medical images and diagnostic reports. It also provides the function to display these information on workstation windows simultaneously by using the designed menu-driven graphic user interface. The medical image compression/decompression techniques are implemented and integrated into the medical image database system for the efficient data storage and the fast access through the network. 30594 T00401030594 ^x In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality. 30608 T00401030608 ^x Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology. 30609 T00401030609 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that is consisted of calcium phosphate and collagen. To use as the structural matrix of the composite, collagen was purified from human umbilical cord. The obtained collagen was treated by pepsin to remove telopeptides, and finally, the immune-free atelocollagen was produced: The cross linked atelocollagen was highly resistant to the collagenase induced collagenolysis. The cross linked collagen demonstrated an improved tensile strength. 30618 T00401030618 ^x This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively. 30619 T00401030619 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased. 30620 T00401030620 ^x We have developed a monoleaflet polymer valve as an inexpensive and viable alternative, especially for short-term use in the ventricular assist device or total artificial heart. The frame and leaflet of the polymer valve were made from polyurethane, To evaluate the hemodynamic performance of the polymer valve a comparative study of flow dynamics past a polymer valve and a St. Jude Medical prosthetic valve under physiological pulsatile flow conditions in vitro was made. Comparisons between the valves were made on the transvalvular pressure drop, regurgitation volume and maximum valve opening area. The polymer valve showed smaller regurgitation volume and transvalvular pressure drop compared to the mechanical valve at higher heart rate. The results showed that the functional characteristics of the polymer valve compared favorably with those of the mechanical valve at higher heart rate. 30621 T00401030621 ^x Explosive evaporative removal process of biological tissue by absorption of a CW laser has been simulated by using gelatin and a multimode Nd:YAG laser. Because the point of maximun temperature of laser-irradiated gelatin exists below the surface due to surface cooling, evaporation at the boiling temperature is made explosively from below the surface. The important parameters of this process are the conduction loss to laser power absorption (defined as the conduction-to-laser power parameter, Nk), the convection heat transfer at the surface to conduction loss (defined as Bi), dimensionless extinction coefficient (defined as Br.), and dimensionless irradiation time (defined as Fo). Dependence of Fo on Nk and Bi has been observed by experiment, and the results have been compared with the numerical results obtained by solving a 2-dimensional conduction equation. Fo and explosion depth (from the surface to the point of maximun temperature) are increased when Nk and Bi are increased.To find out the minimum laser power for explosive evaporative removal process, steady state analysis has been also made. The limit of Nk to induce evaporative removal, which is proportional to the inverse of the laser power, has been obtained. 30622 T00401030622 ^x N1 and N2 gross neural action potentials were measured from the round window of the guinea pig cochlea at the onset of the acoustic stimuli. N1-N2 audiograms were made by means of regulating stimulant intensities in order to produce constant N1-N2 potentials as criteria for different input tone pip frequencies. The lowest threshold was measured with an input tone pip I5 dB SPL in intensity and 12 KHz in frequency when the animal was in normal physiological condition. The procedure of experimental measurements is explained in detail. This experimental approach is very useful for the investigation of the Cochlear function. Both noN1inear and active functions of the Cochlea can be monitored by N1-N2 audiograms. 30623 T00401030623 ^x In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research. 30624 T00401030624 ^x A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells. 30625 T00401030625 ^x An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients. 30626 T00401030626 ^x Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult. 30627 T00401030627 ^x A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator. 30628 T00401030628 ^x The intelligent trajectory control method that controls moving direction and average velocity for a prosthetic arm is proposed by pattern recognition and force estimations using EMG signals. Also, we propose the real time trajectory planning method which generates continuous accelleration paths using 3 stage linear filters to minimize the impact to human body induced by arm motions and to reduce the muscle fatigue. We use combination of MLP and fuzzy filter for pattern recognition to estimate the direction of a muscle and Hogan's method for the force estimation. EMG signals are acquired by using a amputation simulator and 2 dimensional joystick motion. The simulation results of proposed prosthetic arm control system using the EMf signals show that the arm is effectively followed the desired trajectory depended on estimated force and direction of muscle movements. 30638 T00401030638 ^x A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network. 30659 T00401030659 ^x An implementation scheme of the magnetic nerve stimulator using a switching mode power supply is proposed. By using a switching mode power supply rather than a conventional linear power supply for charging high voltage capacitors, the weight and size of the magnetic nerve stimulator can be considerably reduced. Maximum output voltage of the developed magnetic nerve stimulator using the switching mode power supply is 3, 000 volts and switching time is about 100 msec. Experimental results or human nerve stimulations using the developed stimulator are presented. 30768 T00401030768 ^x In this paper, we describe the design methodology and specifications of the developed module-based bedside monitors for patient monitoring. The bedside monitor consists of a main unit and module cases with various parameter modules. The main unit includes a 12.1" TFT color LCD, a main CPU board, and peripherals such as a module controller, Ethernet LAN card, video card, rotate/push button controller, etc. The main unit can connect at maximum three module cases each of which can accommodate up to 7 parameter modules. They include the modules for electrocardiograph, respiration, invasive blood pressure, noninvasive blood pressure, temperature, and SpO2 with Plethysmograph.SpO2 with Plethysmograph.

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