• 콘크리트학회논문집
• /
• 제27권2호
• /
• pp.185-193
• /
• 2015

인장강도 및 휨강도가 낮고 취성파괴의 특성을 가지는 일반적인 콘크리트의 단점을 극복하기 위하여 최근에는 압축강도가 180 MPa이상인 고성능 콘크리트에 강섬유를 혼입한 강섬유 보강 초고성능 콘크리트(UHPC)에 대한 연구가 활발히 진행되고 있다. UHPC 바닥판과 강재 거더를 이용하여 합성보를 구성할 때, UHPC 바닥판의 높은 강도와 강성으로 인하여 강재거더 상부 플랜지의 역할이 거의 불필요할 것으로 예상된다. 이러한 점을 착안하여 본 논문에서는 합성보 구성 시에 강재 거더의 상부플랜지를 없앤 역T형 거더를 적용하였다. 역T형 거더에 UHPC바닥판을 합성하여 합성보를 구성할 경우, 상부플랜지가 없는 이유로 전단연결재의 설치 위치가 상부플랜지 대신에 강재 거더 복부에 설치해야하는 문제점이 발생되며, 강재 복부에 설치되는 전단연결재에 대한 거동, 역T형 강거더 합성보의 휨거동 특성 등은 현재까지 실험 및 이론적으로 평가된 적이 거의 없는 실정인 이유로 이에 대한 연구가 절실하다. 이를 위하여 본 논문에서는 전단연결재 간격, 바닥판 두께 등을 변수로 하여 역T형 거더와 UHPC바닥판을 합성한 합성보를 8개 제작하여 전단연결재의 거동, 휨거동 특성 등을 파악하고자 하였다. 또한, 강섬유 보강 초고성능 콘크리트의 인장연화거동을 고려한 재료모델링 및 이를 적용한 보 부재 단면의 변형률 적합조건을 이용한 해석모델을 제안하였다. 실험결과 및 해석결과를 기준으로 볼 때, UHPC 콘크리트의 경우 전단연결재의 간격은 100 mm에서 바닥판 두께의 2~3배 사이로 규정함이 적절한 것으로 나타났다. 실험결과와 해석결과를 종합적으로 비교하면, 강섬유 보강 초고성능 콘크리트 합성보의 실험결과와 해석결과는 비교적 잘 일치하고 있으므로 재료 실험으로부터 산정된 인장연화곡선은 강섬유 보강 초고성능 콘크리트의 실제 거동을 합리적으로 반영한다고 판단된다. 따라서, 본 연구에서 제시한 인장연화거동 특성을 반영한 강섬유 보강 초고성능 콘크리트의 재료모델링 및 휨거동 해석기법은 적절하며, 제시기법에 의해 강섬유보강 초고성능 콘크리트 합성 부재의 휨 내력을 합리적으로 예측할 수 있을 것으로 예상된다.

• 콘크리트학회논문집
• /
• 제26권6호
• /
• pp.761-769
• /
• 2014

인장강도 및 휨강도가 낮고 취성파괴의 특성을 가지는 일반적인 콘크리트의 단점을 극복하기 위하여 최근에는 압축강도가 180 MPa이상인 고성능 콘크리트에 강섬유를 혼입한 강섬유 보강 초고성능 콘크리트(UHPC)에 대한 연구가 활발히 진행되고 있다. UHPC 바닥판과 강재 거더를 이용하여 합성보를 구성할 때, UHPC 바닥판의 높은 강도와 강성으로 인하여 강재거더 상부 플랜지의 역할이 거의 불필요할 것으로 예상된다. 이러한 점을 착안하여 본 논문에서는 합성보 구성 시에 강재 거더의 상부플랜지를 없앤 역T형 거더를 적용하였다. 역T형 거더에 UHPC바닥판을 합성하여 합성보를 구성할 경우, 상부플랜지가 없는 이유로 전단연결재의 설치 위치가 상부플랜지 대신에 강재 거더 복부에 설치해야하는 문제점이 발생되며, 강재 복부에 설치되는 전단연결재에 대한 거동, 역T형 강거더 합성보의 휨거동 특성 등은 현재까지 실험 및 이론적으로 평가된 적이 거의 없는 실정인 이유로 이에 대한 연구가 절실하다. 이를 위하여 본 논문에서는 전단연결재 간격, 바닥판 두께 등을 변수로 하여 역T형 거더와 UHPC바닥판을 합성한 합성보를 8개 제작하여 전단연결재의 거동, 휨거동 특성 등을 파악하고자 하였다. 실험결과를 기준으로 볼 때, 향후 UHPC의 경우 스터의 간격은 100 mm에서 바닥판 두께의 2~3 배 사이로 규정함이 적절할 것으로 예상된다. 또한 실험 부재의 특성 상대변위는 Eurocode-4의 연성거동 기준에 의하면 충분한 연성 거동을 하는 것으로 판정되었으며, 바닥판이 지나치게 얇고 전단연결재의 간격이 지나치게 넓은 경우를 제외한 대부분의 부재들은 일반 콘크리트보다 UHPC의 성능이 우수하여 기존의 AASHTO LRFD 및 Eurocode-4의 식과 실험결과간의 차이가 있음을 알 수 있다.

• 디자인학연구
• /
• 제17권1호
• /
• pp.211-220
• /
• 2004

새로운 자연과학의 패러다임으로 대두되고 있는 복잡성의 과학인 카오스(Chaos), 프랙탈(Fractal) 이론은 자연을 몇 개의 단순한 요소로 분해 이해하는 것이 아니라 전체적인 관계 속에서 이해하는 것이다. 인간과 자연을 포함한 모든 세계를 바라보는 우리의 시각을 비선형성, 다양성, 시간성, 복잡성으로 향하게 하며 비정수 차원의 자연과 복잡성을 표현하기에 적합한 적용 방법이다. 비선형적 프랙탈 기하학과 카오스 이론을 예술방면으로 응용하는 것은 과학과 예술이 만나는 상상의 영역이며 아직까지 많은 연구가 이루어지지 않은 분야이다. 이러한 프랙탈 형태의 기하학적 특성과 조형 원리를 파악하기 위해 객관적인 자료를 분석해 조형 언어를 추출한 연구이다. 형식에 있어서 수학적인 방법에 의한 프랙탈적 분석이라기보다는 프랙탈의 여러 개념 가운데 특히 자기 유사성(Self-similarity)과 반복성(Recursiveness) 그리고 무작위성(Randomness), 불가능한 공간에 의해 표현되어진 도형과 그래픽디자인과의 조형적인 유사성을 밝혀 보았다. 즉 프랙탈 도형은 부분의 부분, 또 그 부분을 반복해서 확대해 가도 도형의 본직적인 구조가 변하지 않는 특성을 가지고 있다. 이와 같이 무한소까지 확대해도 전체와 일치하는 자기 닮음 구조로 되어있다. 이것은 어느 부분이나 전체를 재구성할 수 있는 정보를 모두 가지고 있음을 뜻한다. 본 연구에서는 이러한 배경을 바탕으로 그래픽디자인에서 나타난 기하학적 조형성에 대한 프랙탈적 분석 가능성을 주로 검토하는 데 목적을 두고 있다. 그리고 연구의 결과 그래픽디자인은 이미 수학적인 계산 속에서 아름다운 비례를 찾고 있었다는 것을 발견할 수 있었다. 자연을 표현하는 가장 적합한 공식인 프랙탈 기하학은 앞으로 과학과 그래픽디자인의 복합체로서 고유성과 특수성의 고부가가치를 창출해야 한다. 이런 요구를 수용하고 변화에 적응 발전해야 하는 필요성이 대두되는 단계에서 본 연구의 의의가 크다고 하겠다.

• 전기화학회지
• /
• 제26권1호
• /
• pp.1-10
• /
• 2023

리튬 이차전지의 4 대 구성요소에 포함되는 양극은 배터리의 에너지 밀도를 담당하는 중요한 구성요소에 속하며, 보편적으로 제작되는 양극의 습식 제작 공정에는 활물질, 도전재, 고분자 바인더의 혼합 과정이 필수적으로 이루어지게 된다. 하지만, 양극의 혼합 조건의 경우 체계적인 방법이 갖추어져 있지 않기 때문에 제조사에 따라 성능의 차이가 발생하는 경우가 대다수이다. 따라서, 양극의 슬러리 제작 단계에서 정돈되지 않은 혼합 방법의 최적화를 진행을 위해 보편적으로 사용되는 THINKY mixer와 homogenizer를 이용한 LiMn₂O₄ (LMO) 양극을 제조해 각각의 특성을 비교하였다. 각 혼합 조건은 2000 RPM, 7 min으로 동일하게 진행하였으며, 양극의 제조 동안 혼합 방법의 차이만을 판단하기 위해 다른 변수 조건들은 차단한 후, 실험을 진행하였다(혼합 시간, 재료 투입 순서 등). 제작된 THINKY mixer LMO (TLMO), homogenizer LMO (HLMO) 중 HLMO는 TLMO보다 더 고른 입자 분산 특성을 가지며, 그로 인한 더 높은 접착 강도를 나타낸다. 또한, 전기화학적 평가 결과, HLMO는 TLMO와 비교하여 개선된 성능과 안정적인 수명 주기를 보였다. 결과적으로 수명특성평가에서 초기 방전 용량 유지율은 HLMO가 69 사이클에서 TLMO와 비교하여 약 4.4 배 높은 88%의 유지율을 보였으며, 속도성능평가의 경우 10, 15, 20 C의 높은 전류밀도에서 HLMO가 더 우수한 용량 유지율과 1C에서의 용량 회복률 역시 우수한 특성을 나타냈다. 이는 활물질과 도전재 및 고분자 바인더가 포함된 슬러리 특성이 homogenizer를 사용할 때, 정전기적 특성이 강한 도전재가 뭉치지 않고 균일하게 분산되어 형성된 전기 전도성 네트워크를 생성할 수 있기 때문으로 간주된다. 이로 인해 활물질과 도전재의 표면 접촉이 증가하고, 전자를 보다 원활하게 전달하여 충전 및 방전 과정에서 나타나는 격자의 부피변화, 활물질과 도전재 사이의 접촉저항의 증가 등을 억제하는 것에 기인한다.

• 한국식품저장유통학회지
• /
• 제31권4호
• /
• pp.660-672
• /
• 2024

본 연구에서는 와송 분말을 첨가한 머핀의 건강식으로서 기능성을 확인하고 첨가량을 0%(Con), 3%(O3), 5%(O5), 7%(O7), 9%(O9)로 달리하여 머핀의 품질 특성과 항산화 활성 및 기호도를 측정함으로써 최적의 첨가량을 제시하고 와송 첨가식품에 대한 기초자료를 제공하고자 하였다. 와송 쌀 머핀의 수분함량은 와송 분말의 첨가량이 증가함에 따라 머핀의 수분함량이 감소하였으나, O3은 대조군과 유의적인 차이를 보이지 않았으며, O5, O7 및 O7은 시료 간 유의적인 차이가 나타나지 않았다. pH는 첨가량이 증가함에 따라 유의적으로 감소하였으며, 무게는 와송 분말 첨가량이 증가함에 따라 유의적으로 증가하였지만, O7과 O9 시료 간 유의적인 차이는 없었다. 부피는 와송 분말 첨가량이 증가함에 따라 유의적으로 감소하는 경향이 나타났고, 비체적과 굽기손실률은 와송 분말 첨가량이 증가할수록 유의적으로 감소하였다. 머핀의 색도는 첨가량이 증가할수록 L값이 유의적으로 감소하였고(p<0.001), a값(+red/-green)은 유의적으로 증가하는 경향을 보였으며, b값(+yellow/-blue)은 와송 분말 첨가량이 증가함에 따라 감소하였지만, 와송 분말 첨가군 사이에서 유의적인 차이가 나타나지 않았다. 조직감을 측정한 결과, 경도, 검성, 씹힘성은 유의적으로 증가하였고, 부착성, 탄력성, 응집성은 유의적으로 감소하였다. 폴리페놀, 플라보이드, DPPH 및 ABTS⁺ radical 소거활성, 환원력은 와송 분말 첨가량이 증가함에 따라 유의적으로 증가하였다. 관능검사는 외관, 색, 향, 맛, 조직감, 전체적인 기호도에서 5-7% 첨가군에서 높은 점수가 나타났으며, 9% 첨가군에서 가장 낮게 측정되었다. 특성강도 평가 항목인 와송의 향과 쓴맛의 정도에서는 와송 분말의 첨가량이 증가함에 따라 증가하였으며, 촉촉함 정도에서 감소하였다. 따라서 와송 분말을 5-7% 첨가하는 것이 머핀의 품질 특성과 기호도에 긍정적인 영향을 주고, 항산화활성을 증가시킬 수 있어 바람직한 것으로 생각된다. 또한, 본 연구를 통해 와송 분말의 활용 가능성과 쌀 가공제품의 개발 가능성을 확인하였다.

• 한국전통조경학회지
• /
• 제32권3호
• /
• pp.32-45
• /
• 2014

본 연구는 편액과 시문이 과거 누정원림의 고유한 입지 및 조영 특성 추론의 중요한 준거(準據)가 된다는 전제 하에, 요월정원림(邀月亭園林)을 대상으로 과거 시점의 입지 및 조영 해석을 고구(考究)하기 위해 시도되었다. 요월정원림이 갖는 의미와 문화재적 위상과 가치의 진정성 제고 및 보존의 당위성을 논의할 목적으로 시도된 연구결과는 다음과 같다. 첫째, 요월정원림은 정원주 김경우(金景遇)를 비롯한 당대 거유들이 교유한 시율풍류의 현장이었다. "조선환여승람 호남읍지(湖南邑誌) 장성읍지(長城邑誌)" 등 고문헌을 통해 사화(士禍)를 피해 머문 은신처로서의 성격과 함께 지역정체성을 형성한 교두보로서의 장소성이 확인되었다. 또한 "요월정원운(邀月亭原韻)"을 통해 누정원림 작정(作庭) 의도 및 조영 동기를 확인한 바, 요월정원림은 세속과 탈속 그리고 현실과 이상이 뒤섞여 길항(拮抗)한 공간으로 해석된다. 둘째, 당호 요월(邀月)은 누정에서 조망했을 때의 승경적 요인 및 자연현상과 관련된 명칭으로, 마주한 '월봉산에 뜨는 달을 맞이함'을 함의하는 어휘로, 이는 자연의 섭리이자 풍류로서 탈속의 이미지와 맞닿아 있다. 즉 요월정은 세속의 희비를 벗어나 자연의 섭리를 따르려한 조영 의도를 반영한 당호로 해석된다. 셋째, 요월정원림의 입지는 "영광속수여지승람(靈光續修輿地勝覽)"을 통해 조영자가 퇴관 후 휴식을 위해 마련한 처소였으며, 월봉산을 마주하여 황룡강(黃龍江)이 굽이쳐 흐르던 승경지였음을 고문헌과 다수의 시문을 통해 확인하였다. 특히, 수호인 인터뷰에 따르면 요월정원림에서 야경의 시지각 빈도(頻度)는 수호인 거처인 고직사에서 요월정을 향해 황룡강 방향인 동쪽을 숙시각(熟視角)으로 조망했을 때가 가장 높다고 한다. 또한 시지각 강도(强度)가 가장 높고 아름다운 풍경은 요월정 좌측 배후면에서 달이 부상하여 요월정 전면(前面)의 배롱나무동산을 가로질러 요월정과 마주한 월봉산 사이에 남중한 때로 증언한 바 있다. 현재 요월정원림의 좌향은 $SE\;141.2^{\circ}$로서 거의 남동향 하고 있는데, 이와 같은 요월정 좌향 설정은 지형조건뿐 아니라 달의 궤적을 유상(遊賞)하기에 최적화된 방향과 시계(視界)를 확보하기 위한 기도(企圖)가 담겼다고 판단된다. 나아가 전면의 황룡강 수면 위로 남중한 달빛이 투영됨으로써, 하늘의 달과 황룡강 강물에 투영된 달이 동시에 감지되게끔 고려된 것으로 추론된다. 넷째, 현재 요월정원림은 요월정과 광산김씨문숙공파종회각(光山金氏文肅公派宗會閣) 및 고직사(庫直舍)로 구성된 '내원 권역'과 진입부를 아우른 배롱나무동산 및 소나무 배후림이 포함된 '외원 권역'으로 구분된다. 나아가 '용소 및 수생식물원 권역' 및 최근 조성된 '황룡정과 공원 권역'으로 외연(外緣)이 확산되면서 교란되고 변용되었다. 다섯째, 조영 당시 요월정원림은 누정에서 조망한 풍경을 안아 들여 누정을 중심으로 지근거리의 일정한 자연을 점유한 방식인 '경계 없는 산수원림'이었으나, 현재 복합경관은 과거 원형경관과는 괴리된 '이질화 분절화 파편화된' 경관으로 파악된다. 마지막으로, 요월정원림이 문화재지정보호구역임을 감안할 때, 편액과 기문에 묘사된 완전한 원형경관으로의 복원은 아니더라도 최소한 원림권역에서의 경관적 악영향과 시각적 훼손을 최소화하기 위한 대책수립이 요망된다.

• 한국전통조경학회지
• /
• 제32권1호
• /
• pp.93-106
• /
• 2014

본 연구는 천연기념물 제374호 제주 평대리 비자나무 숲의 입지환경, 식생자원과 이용 및 관리현황을 조사하고, 현재 적용되는 관리구역에 대한 등급을 설정한 것으로써 다음과 같은 결과를 도출하였다. 첫째, 제주 평대리 비자나무 숲은 토지이용형태가 농업지역으로 변화하면서 대상지 주변지역으로의 개발압력에 의한 영향이 우려되며, 비자나무 숲 내 곶자왈지대는 종 다양성을 확보할 수 있는 기반요소로 원형보존의 관리계획 설정 및 지형의 변화를 야기하는 개발행위는 배제되어야 한다. 둘째, 제주 평대리 비자나무 숲의 소산식물상은 총 91과 263속 353종 41변종 8품종의 402분류군이 조사되었다. 이 중 환경부 지정 법정 멸종위기식물종 중 멸종위기식물 I II급에 해당하는 식물의 분포가 확인되었으나 현재의 서식처 변화 및 종의 병해, 불법 남획 등에 따른 개체 소실에 의해 비자나무 숲 내 종의 절멸 위험도 존재하므로 제주 평대리 비자나무 숲의 관리방안 설정 시 우선적으로 보호되어야 할 대상으로 고려되어야 한다. 셋째, 비자나무가 상관을 대표하는 식생구조를 나타내고 있으나, 노거수 위주의 영속적 관리와 보존전략은 빈약한 연령구조를 야기하였으며, 일부 구역의 인위적 관리에 의한 숲의 건조화, 자연적 천이에 의한 비자나무의 입지 감소 등의 문제점이 발생하는 바, 수목밀도의 조절 및 후계목 증식 등 제주 평대리 비자나무 숲의 특성을 유지할 수 있는 방안의 마련이 필요하다. 넷째, 이용에 따른 탐방로의 훼손이 발견되었으며, 특히 화산송이길의 훼손 및 분담율이 높게 나타났다. 따라서 화산송이의 단순한 보충보다는 현행 탐방로 외에 추가적인 관광루트 개발을 통한 분담율 완화 방안이 고려되어야 한다. 섯째, 제주 평대리 비자나무 숲의 관광요소 중 높은 선호도를 나타내는 식물적 요소는 이용에 관한 압력이 민감하게 작용하고, 비영속적인 특성상 지속적 모니터링이 필요하며, 추가적 관광요소 개발과 동시에 현재 높은 선호도를 나타내는 요소를 적극 활용하는 등의 방안이 마련되어야 한다. 여섯째, 보호강도별 중요도에 따라 I등급 지역은 존속개체군의 유지와 서식처의 훼손을 방지하고, II등급 지역은 연차별 숲의 재생을 위주로 관리방향을 설정하며, III등급 지역은 비자나무 시범림이나 후계목 증식을 위한 지역으로 설정되어야 한다. IV등급 지역은 고유 식생의 교란이 많이 발생하는 곳으로 부분별 휴식년제의 도입이 필요하다. V등급 지역은 비자나무 숲의 관광활용을 위한 서비스 공간 적지에 속한다. 상이한 등급의 지역 인접에 따른 가장자리효과에 대한 방안으로는 상대적으로 등급이 낮은 곳에 환경간섭을 피하기 위한 버퍼존의 설치와 주기적 모니터링이 요구된다.

• Asia pacific journal of information systems
• /
• 제20권3호
• /
• pp.139-166
• /
• 2010

The supply chain management (SCM) systems have emerged as strong managerial tools for manufacturing firms in enhancing competitive strength. Despite of large investments in the SCM systems, many companies are not fully realizing the promised benefits from the systems. A review of literature on adoption, implementation and success factor of IOS (inter-organization systems), EDI (electronic data interchange) systems, shows that this issue has been examined from multiple theoretic perspectives. And many researchers have attempted to identify the factors which influence the success of system implementation. However, the existing studies have two drawbacks in revealing the determinants of systems implementation success. First, previous researches raise questions as to the appropriateness of research subjects selected. Most SCM systems are operating in the form of private industrial networks, where the participants of the systems consist of two distinct groups: focus companies and vendors. The focus companies are the primary actors in developing and operating the systems, while vendors are passive participants which are connected to the system in order to supply raw materials and parts to the focus companies. Under the circumstance, there are three ways in selecting the research subjects; focus companies only, vendors only, or two parties grouped together. It is hard to find researches that use the focus companies exclusively as the subjects probably due to the insufficient sample size for statistic analysis. Most researches have been conducted using the data collected from both groups. We argue that the SCM success factors cannot be correctly indentified in this case. The focus companies and the vendors are in different positions in many areas regarding the system implementation: firm size, managerial resources, bargaining power, organizational maturity, and etc. There are no obvious reasons to believe that the success factors of the two groups are identical. Grouping the two groups also raises questions on measuring the system success. The benefits from utilizing the systems may not be commonly distributed to the two groups. One group's benefits might be realized at the expenses of the other group considering the situation where vendors participating in SCM systems are under continuous pressures from the focus companies with respect to prices, quality, and delivery time. Therefore, by combining the system outcomes of both groups we cannot measure the system benefits obtained by each group correctly. Second, the measures of system success adopted in the previous researches have shortcoming in measuring the SCM success. User satisfaction, system utilization, and user attitudes toward the systems are most commonly used success measures in the existing studies. These measures have been developed as proxy variables in the studies of decision support systems (DSS) where the contribution of the systems to the organization performance is very difficult to measure. Unlike the DSS, the SCM systems have more specific goals, such as cost saving, inventory reduction, quality improvement, rapid time, and higher customer service. We maintain that more specific measures can be developed instead of proxy variables in order to measure the system benefits correctly. The purpose of this study is to find the determinants of SCM systems success in the perspective of vendor companies. In developing the research model, we have focused on selecting the success factors appropriate for the vendors through reviewing past researches and on developing more accurate success measures. The variables can be classified into following: technological, organizational, and environmental factors on the basis of TOE (Technology-Organization-Environment) framework. The model consists of three independent variables (competition intensity, top management support, and information system maturity), one mediating variable (collaboration), one moderating variable (government support), and a dependent variable (system success). The systems success measures have been developed to reflect the operational benefits of the SCM systems; improvement in planning and analysis capabilities, faster throughput, cost reduction, task integration, and improved product and customer service. The model has been validated using the survey data collected from 122 vendors participating in the SCM systems in Korea. To test for mediation, one should estimate the hierarchical regression analysis on the collaboration. And moderating effect analysis should estimate the moderated multiple regression, examines the effect of the government support. The result shows that information system maturity and top management support are the most important determinants of SCM system success. Supply chain technologies that standardize data formats and enhance information sharing may be adopted by supply chain leader organization because of the influence of focal company in the private industrial networks in order to streamline transactions and improve inter-organization communication. Specially, the need to develop and sustain an information system maturity will provide the focus and purpose to successfully overcome information system obstacles and resistance to innovation diffusion within the supply chain network organization. The support of top management will help focus efforts toward the realization of inter-organizational benefits and lend credibility to functional managers responsible for its implementation. The active involvement, vision, and direction of high level executives provide the impetus needed to sustain the implementation of SCM. The quality of collaboration relationships also is positively related to outcome variable. Collaboration variable is found to have a mediation effect between on influencing factors and implementation success. Higher levels of inter-organizational collaboration behaviors such as shared planning and flexibility in coordinating activities were found to be strongly linked to the vendors trust in the supply chain network. Government support moderates the effect of the IS maturity, competitive intensity, top management support on collaboration and implementation success of SCM. In general, the vendor companies face substantially greater risks in SCM implementation than the larger companies do because of severe constraints on financial and human resources and limited education on SCM systems. Besides resources, Vendors generally lack computer experience and do not have sufficient internal SCM expertise. For these reasons, government supports may establish requirements for firms doing business with the government or provide incentives to adopt, implementation SCM or practices. Government support provides significant improvements in implementation success of SCM when IS maturity, competitive intensity, top management support and collaboration are low. The environmental characteristic of competition intensity has no direct effect on vendor perspective of SCM system success. But, vendors facing above average competition intensity will have a greater need for changing technology. This suggests that companies trying to implement SCM systems should set up compatible supply chain networks and a high-quality collaboration relationship for implementation and performance.

• 대한의용생체공학회:의공학회지
• /
• 제6권2호
• /
• pp.1-8
• /
• 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.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 1993년도 한국우주과학회보 제2권2호
• /
• pp.17-17
• /
• 1993

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.