• 자원환경지질
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• 제22권2호
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• pp.91-102
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• 1989

The gravity measurement has been conducted at 61 stations with an interval of about 500 to 1,000 m along two survey lines of about 47 Km between $Chungju-Jech{\check{o}}n$ and $Salmi-D{\check{o}}cksanmy{\check{o}}n$ in order to study on the subsurface geologic structure and structural relation between $Okch{\check{o}}n$ Group and Great Limestone Group of $Chos{\check{o}}n$ Supergroup. The Bouger gravity anomalies were obtained from the reduction of the field observations, and the distribution patterns of the basement and subsurface geologic structure were interpreted by means of the Fourier-Series and Talwani method for two-dimensional body. The depth of Conrad discontinuity varies from 12.7 Km to 15.7 Km, and vertical displacements along the Osanri and Bonghwajae faults are 1.0 Km and 1.5 Km, respectively between Chungju and $Jech{\check{o}}n$. The depth of Conrad discontinuity varies from 13.8 Km to 15.4 Km, and vertical displacement along the Bonghwajae fault is 0.5 Km between Salmi and $D{\check{o}}cksanmyon$. The basement is widely exposed at several places between Chungju and $Jech{\check{o}}n$. In the unexposed area between Osanri and $W{\check{o}}lgulri$, its depth is from 1.5 Km to 2.1 Km. It is displaced downward along the Osanri and Bonghwajae faults by 0.8 Km and 0.6 Km, respectively, and is displaced upward along the Dangdusan fault by 1.6 Km. On the other hand, the depth of the basement varies abruptly by the Sindangri, Jungwon, Kounri, and Bonghwajae faults between Salmi and $D{\check{o}}cksanmy{\check{o}}n$, and it is from 2.8 Km to 3.2 Km around $Salmimy{\check{o}}n$, from 1.6 Km to 2.5 Km between the Sindangri and Bonghwajae faults, 3.0 Km near Koburangjae, and 2.5 Km at $Doj{\check{o}}nri$. The high Bouguer gravity anomalies are due to the accumulation of $Okch{\check{o}}n$ Group and $Jangs{\check{o}}nri$ Metamorphic Complex whose density is higher than the basement exposed between Sondong and Osanri, and imply the existance of Bonghwajae Metabasite or hornblende gabbro of high density distributed along the Bonghwajae fault in the vicinity of Koburangjae. The low Bouguer gravity anomalies resulted form the fracture zone associated with fault or rock of low density imply the existance of the Osanri, Bonghwajae, Dangdusan faults and $Daed{\check{o}}cksan$ thrust between Chungju and $Jech{\check{o}}n$, the uplift of the basement by the Sindangri, Jungwon, Kounri, and Bonghwajae faults, and extensive distribution of Cretaceous biotite granites between Salmi and $Docksanmy{\check{o}}n$. The thickness of $Okch{\check{o}}n$ metasediments varies from 1.5 Km to 3.2 Km, and that of Great Limestone Group of $Chos{\check{o}}n$ Supergroup from 200 m to 700 m. It is interpreted that $Okch{\check{o}}n$ Group is in contact with Great Limestone Group of $Chos{\check{o}}n$ Supergroup by the fault zones of the Bonghwajae and $Daed{\check{o}}cksan$ faults, and the Bongwhajae fault is a thrust of high angle, by which the east of the basement is displaced downward 0.5 Km between Chungju and lechon, and 1.0 Km between Salmi and $D{\check{o}}cksanmy{\check{o}}n$.

• 대한치과교정학회지
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• 제34권1호
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• pp.93-107
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• 2004

Enlow의 구조적 대응체 분석법은 다수의 평균에 의한 정상치와 비교하는 분석법과는 달리 개개인에서 두 개안면의 구성양상이 발달되어온 해부학적, 발육학적 특징의 복합체를 설명하는 방법이다. 본 연구에서는 악교정 수술을 시행한 골격성 III급 부정교합 환자 80명(남자 40명, 여자 40명)을 대상으로 구조적 대응체 분석법을 이용하여 수술 전후를 비교하고, 정상교합자와 비교하여 다음과 같은 결과를 얻었다. 1. 수술에 의해서 주로 하악지 전후방 길이(B3)가 감소되어 상하악의 전후방적 부조화가 해소되었다. 2. 수술에 의해서 하악지의 배열(R3, R4)이 후방으로 재배열되었으며 교합평면(R5)은 후하방으로 회전되었다. 3. 수술후와 정상교합자의 비교결과 수술후에 골격성 III급 양상은 해소되었으나 두개저수준(R1, R2)에서는 차이를 보이고 있다. 4. 수술방법에 따른 비교결과 양악수술은 상악골의 길이(A4), 하악지의 배열(R3, R4), 교합평면의 각도(R5)에서 하악수술과 차이를 보였으나 두 그룹간의 차이는 크지 않았다. 한국인 골격성 III급 부정교합자의 특징을 살펴본 지난 연구에서 골격적 원인은 두개저의 후상방회전, 상악골의 후방위치, 하악지의 전방경사, 하악골체부의 길이증가였는데 본 연구 결과 실제 수술에서 개선되는 요소는 주로 하악지의 전후방 길이 감소, 상악골의 전진이기 때문에 상대적인 개선으로 골격성 III급 양상이 해소되었다고 볼 수 있다. 이러한 결과는 실제적인 수술부위가 상악골과 하악골의 일부에 국한되기 때문이다.

• 대한방사선치료학회지
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• 제21권2호
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• pp.83-88
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• 2009

목 적: 온 보드영상(OBI)장치를 이용한 콘빔CT는 환자 치료 중 실시간으로 전산화모의치료 영상과 비교하여 환자의 자세 및 표적용적의 움직임과 셋업오차를 확인 할 수 있다. IMRT 시 콘빔CT를 이용해 환자의 자세 및 표적용적의 변화와 움직임을 확인하여 치료계획과의 오차정도를 산출하고, Automatic Match System을 이용하여 위치 보정을 한 후 전자포털영상 장치를 통하여 위치보정의 정확성을 검증하고, IMRT에서 콘빔CT의 유용성과 Automatic Match System의 정확성에 대하여 알아보고 자 한다. 대상 및 방법: 본원에서 치료받은 IMRT 환자 중 두 경부 치료환자 3명, 골반부 치료환자 1명을 대상으로 치료 자세의 변동과 그에 따른 조사용적의 위치변동을 알아보기 위해 선형가속기에 장착된 온 보드 영상 장치를 이용해 콘빔 CT를 촬영하였다. IMRT 전 매 치료 시 마다 콘빔CT를 촬영하여 전산화단층모의치료 영상과 비교하여 좌표별로 치료계획과의 오차값을 확인하고 3D/3D Match의 Automatic Match System을 통하여 치료계획과 일치하도록 이동 보정한 후 전자포털영상 장치를 이용하여 검증, 평가하였다. 결 과: 치료 전 콘빔 CT와 전산화단층모의치료 영상 비교 시 두 경부에서 좌표별 평균오차는 Vertical 0.99 mm, Longitudinal 1.14 mm, Lateral 0.84 mm, Rotation $0.49^o$이고, 골반부의 평균오차는 Vertical 2.78 mm, Longitudinal 2.04 mm, Lateral 4.91 mm, Rotation $1.07^o$로 부위별로 다소 근소한 차이를 보였다. 보정 후 검증에서는 전자포털영상 장치에 의한 영상과 DRR 영상 비교 결과 0.5 mm 이내의 오차로 정확한 보정이 이루어졌음을 알 수 있었다. 결 론: 치료 전 콘빔CT 영상은 환자의 셋업오차와 장기 및 표적의 위치변화를 2차원적 영상의 비교와 달리 하나의 체적으로 재구성된 3차원적 영상으로 비교함으로써 보다 정확하게 위치변화와 표적용적의 변동 등을 측정, 보정하여 정확한 치료를 할 수 있으며, 그 오차 값을 산출하여 비교할 수 있다. 이상의 연구로 보아 콘빔CT는 치료계획과 일치하는 정확한 치료전달과 반복적인 치료재현성에 유용하였으며, 만족스러운 결과를 얻을 수 있었다. 콘빔CT에 의해 향상된 정확도는 복잡한 모양의 표적용적과 급격한 선량분포의 변화가 나타나는 IMRT에서 더욱 필요하며 각 치료 부위별, 치료 목적별로 Match focus에 대한 기준을 연구해야 될 것으로 사료된다.

• 구강회복응용과학지
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• 제24권2호
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• pp.213-230
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• 2008

최근 치료기간의 단축과 심미성을 동시에 충족시키는 6전치를 설측에서 견인하는 레버암을 이용한 견인방법이 사용되고 있다. 본 연구에서는 상악골의 고전적인 2가지 물성으로 구성된 유한 요소 모델 (단순모델)과 새로이 개발된 24가지 물성으로 구성된 모델 (복합모델)을 생성하여 상악 6전치를 후방 견인 시, 각 치아와 치주인대에 나타나는 초기 이동량과 응력분포를 분석하였다. 23세 성인 남자의 CT 촬영으로 얻은 DICOM 영상정보를 3차원 리버스 엔지니어링 컴퓨터영상프로그램 Mimics를 이용하여 상악골 및 상악 전치부의 3차원 입체영상모델로 재구성하여 finite element analysis (FEA) 모델을 완성하였다. 모델은 상악골, 상악 전치부 각 치아의 치주인대, lingual traction arm의 부분으로 구성되었다. 상악 6전치의 저항중심 부위를 지나도록 교합면에 대하여 평행하게 200g의 후방견인력을 적용한 후 나타나는 초기 이동량 및 응력 분포를 3차원 유한 요소법을 이용한 해석을 통해 비교하였다. 실험 결과 24가지 물성으로 구성된 복합모델이 2가지 물성으로 구성된 단순 모델에 비해 상악 중절치에서 보다 후방 이동되는 양상이 크게 나타났으며 수직적인 회전 양상 역시 크게 나타났다. 두 모델 모두 중절치와 측절치는 조절성 경사이동의 형태로 후방이동양이 견치보다 크게 나타났으나 견치는 이동량이 적은 대신 치근의 이동이 더 크게 나타났다. 수직적 이동양상에 있어 두 모델 모두 측절치와 견치의 접촉점을 중심으로 절치는 하방으로 견치는 상방으로 움직이는 회전양상을 나타났다. 응력의 비교에서는 단순 모델과 복합 모델에서 유사한 결과를 보였다. 비록 각기 다른 물성으로 인해 후방 이동량에서는 차이가 나타났으나 기본적인 치아의 이동양상은 두 모델에서 모두 같게 나타났다.

• 대한치과교정학회지
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• 제26권1호
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• pp.17-32
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• 1996

여러가지 교정장치 중에서 고정성 장치는 개개치아의 이동에 있어 가장 효과적으로 사용되는 장치이므로 그 작용기전과 역학적 관계를 이해하는 것이 중요하다. 고정성 장치의 탄선형태는 크게 continuous arch, segmented arch, sectional arch로 나누어 볼수있는데, segmented arch나 sectional arch는 힘의 작용점이 단순하고 interbracket distance도 길어 술자 임의대로 force system 조절이 가능한 반면 continuous arch에 서는 bracket geometry가 다양하고, interbracket distance가 좁아 force system의 조절이나 그 역학적 분석이 어려운게 사실이다. 저자는 공학에서의 3 dimensional elastic beam이 continuous arch의 형태와 유사한 점에 착안하여 continuous arch 의 force system을 분석하고자 하였으며, 이를 위해 다양한 형상을 갖는 3개의 bracket geometry를 표본형상으로 설정하고 기울기, 변위 및 interbracket distance에 따른 힘과 moment의 변화양상을 분석하고, 저자가 임의로 제작한 불규칙한 치아배열을 갖는 3차원 모형을 일례로하여 0.016 NiTi archwire를 bracket내에 삽입했을 때 발생되는 초기 힘과 moment를 분석 비교해본 결과 다음과 같은 결론을 얻었다. 1. Bracket의 변위 또는 기울기에 따라 나타나는 힘의 양상이 선형 대칭적인 비례관계를 보였다. 2. Interbracket distance에 따라 나타나는 힘의 양상은 비선형 대칭적인 반비례관계를 보였다. 3. 3차원 모형에서 bracket 형상이 비교적 단순한 부위에서는 표본형상과 비교분석이 가능했지만 인접치의 형상이 복잡한 부위에서는 표본형상의 예측량보다 힘이 크게 발생 되었다.나타나지 않았다. 하악의 arch length discrepancy는 하악 절치의 MD/FL index와, 상악의 arch length discrepancy는 측절치의 MD/FL index에서 상관관계를 나타내었다. 4. 정상군과 밀집군의 각 계측항목의 t-검정 결과 하악의 arch length discrepancy, overbite에서만 유의차를 나타내었다. 검사에서 Plaque Index(p<0.01)와 Gingival Index(p<0.001)가 상당히 낮은것으로 나타났다. 겔형 불화주석군에서 한 증례는 미미한 치관착색을, 두 증례는 보통정도의 치관착색을 보였다. 치아탈회 연구에서는 겔형 불화주석군과 불화나트륨 양치액군이 치료후 치아탈회값에서 치료전 치아탈회값을 뺀 치아탈회값이 대조군에 비해 구강전체및 제1대구치에서 현저하게 낮은 값(p<0.05)을 보였다. 비록 겔형 불화주석군이 불화나트륨 양치액군보다 일관되게 낮은 치아탈회값을 보였을지라도 통계적으로 그 차이는 단지 유의성을 보이는 정도였다.는 골기질의 주성분인 type I 교원질의 합성을 선택적으로 억제하는 기능과 alkaline phosphatase의 활성을 크게 증가시키지 못한 점 등으로 미루어 볼 때, 골개조를 억제하는 방향으로 작용한다고 볼 수 있으며, 교정치료 과정중 골개조를 억제하는 부위에서 사용을 시도해 볼 수 있겠다.>신뢰구간은 상악에서 정상교합군은 $79.5-81.0\%$, 비발치군은 $81.6-84.9\%$, 발치군은 $70.1-72.2\%$로 나타났으며, 하악에서 정상교합군은 $79.8-82.2\%$, 비발치군은 $82.1-85.5\%$, 발치군은 $73.1-75.1\%$로 나타났다. 7. 최대치아근원심폭경합, 기저악궁폭경, 기저악궁장경, 최대치아근원심폭경 합에 대한

• 구강회복응용과학지
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• 제28권2호
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• pp.147-161
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• 2012

본 연구에서는 유한요소해석 방법을 사용하여 임플란트 지지 3본 고정성 가공 의치에 수평적인 부적합이 존재할 때 그 정도가 임플란트 인접골 응력 발생에 미치는 영향에 대해 조사하였다. 3본 고정성 가공의치, 임플란트/악골 복합체로 구성된 해석 모델은 3차원으로 연구되었다. 3본 고정성 가공의치의 체결 간격은 하악 제2 소구치와 제2 대구치에 17.9mm 거리로 식립된 임플란트 간격에 비해 0.1mm 짧거나(17.8mm), 0.1mm 길게(18.0mm) 모델링하였다. 3본 고정성 가공의치와 임플란트 지대주 간의 체결은 총 6단계로 모사되었고 각 단계별로 가공의치가 하방으로 0.1mm 씩 변위되었다. 유한요소해석에는 PC용으로 출시된 DEFORM$^{TM}$ 3D 프로그램(ver 6.1, SFTC, Columbus, OH, USA)을 사용하였다. 3본 고정성 가공의치와 임플란트 사이의 응력은 von-Mises 응력, 최대 압축 응력, 필요한 경우 방사상 응력을 평가하였다. d=18.0mm인 모델에서는 가공의치와 지대주간의 체결이 이루어지지 않은 반면, d=17.8mm 인 모델에서는 성공적으로 체결이 가능했다. 체결 여부를 떠나 과도하게 높은 응력이 체결과정과 그 이후에 발생되었는데, 17.8mm 모델의 경우 체결완료 후에도 임플란트 주위 변연골에서 잔류하는 인장 및 압축 응력이 각각 최대 186.9MPa과 114.1MPa이었다. 이 경우 임플란트로부터 2mm 떨어진 부분까지 압축 응력이 골개조 장애 임계 응력인 55MPa($4,000{\mu}{\varepsilon}$과 같은 크기)보다 크게 측정되었다. 3본 고정성 가공의치의 0.1mm 크기의 수평적 부적합은 체결 과정뿐만 아니라 완료 후에도 인접 변연골에 높은 응력을 발생시킬 수 있다.

• 한국터널지하공간학회 논문집
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• 제24권6호
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• pp.451-464
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• 2022

고준위방사성폐기물 처분장은 심지층 처분시스템으로 사용후핵연료를 취급하는 특성상 고온, 방사선 및 지하수 등의 복합적인 환경조건에 노출되어 있다. 지속적인 노출에 의해 시간이 지남에 따라 구조물의 균열 및 열화가 발생할 수 있다. 한편 고준위방사성폐기물 처분장은 초장기 기대수명이 요구되며 이에 따른 장기적인 구조물 건전성 모니터링이 필수적이다. 구조물 건전성 모니터링에는 가속도계, 토압계, 변위계 등 다양한 센서들이 활용될 수 있으며, 이 중 일반적으로 피에조센서가 사용된다. 따라서 피에조센서의 내구성 평가를 바탕으로 고내구성 센서를 개발할 필요가 있다. 본 연구에서는 피에조센서의 내구성 평가 및 수명예측을 위한 가속수명시험을 설계하였다. 문헌연구를 바탕으로 단일 스트레스 인자에 대한 가속 스트레스 수준 수 및 각 수준 별 시료 수를 선정하였다. 또한 고준위방사성폐기물 처분장 환경조건에서 발생할 수 있는 피에조센서의 고장모드 및 고장메커니즘을 분석하였다. 온도 스트레스 인자에 대한 최대 가혹조건 탐색 실험을 두 가지 방법으로 제안하였으며 피에조센서의 신뢰도 높은 동작한계를 도출하였다. 이를 이용하여 가속수명시험의 합리적인 가속 스트레스 수준을 설정하였다. 본 연구에서 제시된 최대 가혹조건 탐색 실험방법은 경제적이며 실용적인 아이디어를 담고 있으며, 추후 피에조센서의 가속수명시험 설계에 널리 활용될 수 있을 것으로 판단된다.

• 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.

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