• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.252-252
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• 2017

Nowadays water shortage is becoming one of the biggest problems in the Korea. Many different methods are developed for conservation of water. Soil water management has become the most indispensable factor for augmenting the crop productivity especially on soybean (Glycine max L.) because of their high susceptibility to both water stress and water logging at various growth stages. The farmers have been using irrigation techniques through manual control which farmers irrigate lands at regular intervals. Automatic irrigation systems are convenient, especially for those who need to travel. If automatic irrigation systems are installed and programmed properly, they can even save you money and help in water conservation. Automatic irrigation systems can be programmed to provide automatic irrigation to the plants which helps in saving money and water and to discharge more precise amounts of water in a targeted area, which promotes water conservation. The objective of this study was to determine the possible effect of automatic irrigation systems based on soil moisture on soybean growth. This experiment was conducted on an upland field with sandy loam soils in Department of Southern Area Crop, NICS, RDA. The study had three different irrigation methods; sprinkle irrigation (SI), surface drip irrigation (SDI) and fountain irrigation (FI). SI was installed at spacing of $7{\times}7m$ and $1.8m^3/hr$ as square for per irrigation plot, a lateral pipe of SDI was laid down to 1.2 m row spacing with $2.3L\;h^{-1}$ discharge rate, the distance between laterals was 20 cm spacing between drippers and FI was laid down in 3m interval as square for per irrigation plot. Soybean (Daewon) cultivar was sown in the June $20^{th}$, 2016, planted in 2 rows of apart in 1.2 m wide rows and distance between hills was 20 cm. All agronomic practices were done as the recommended cultivation. This automatic irrigation system had valves to turn irrigation on/off easily by automated controller, solenoids and moisture sensor which were set the reference level as available soil moisture levels of 30% at 10cm depth. The efficiency of applied irrigation was obtained by dividing the total water stored in the effective root zone to the applied irrigation water. Results showed that seasonal applied irrigation water amounts were $60.4ton\;10a^{-1}$ (SI), $47.3ton\;10a^{-1}$ (SDI) and $92.6 ton\;10a^{-1}$ (FI), respectively. The most significant advantage of SDI system was that water was supplied near the root zone of plants drip by drip. This system saved a large quantity of water by 27.5% and 95.6% compared to SI, FI system. The average soybean yield was significantly affected by different irrigation methods. The soybean yield by different irrigation methods were $309.7kg\;10a^{-1}$ from SDI $282.2kg\;10a^{-1}$ from SI, $289.4kg\;10a^{-1}$ from FI, and $206.3kg\;10a^{-1}$ from control, respectively. SDI resulted in increase of soybean yield by 50.1%, 7.0% 9.8% compared to non-irrigation (control), FI and SI, respectively. Therefore, the automatic irrigation system supplied water only when the soil moisture in the soil went below the reference. Due to the direct transfer of water to the roots water conservation took place and also helped to maintain the moisture to soil ratio at the root zone constant. Thus the system is efficient and compatible to changing environment. The automatic irrigation system provides with several benefits and can operate with less manpower. In conclusion, improving automatic irrigation system can contribute greatly to reducing production costs of crops and making the industry more competitive and sustainable.

• 핵의학기술
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• 제14권1호
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• pp.61-66
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• 2010

VDT는 Video Display Terminals의 약어로 시각 표시 단말기를 뜻한다. 최근 핵의학과에 VDT가 대량 보급되면서 점차적으로 사용자들이 늘어남과 동시에 사용 기간이 급증함에 따라 VDT 증후군에 관심이 높아지고 있다. 본 연구는 서울대학교병원 핵의학과를 대상으로 VDT 유해 요인 평가 도구를 적용하여 그 실태를 조사하고 문제점을 발견하여 향후 개선에 관한 방안을 도출함으로써 VDT 증후군에 관한 의식을 정립하고 궁극적으로 예방하는 데 목적이 있다. 서울대학교병원 핵의학과를 본원 핵의학과, 소아 핵의학과, PET 센터의 3개 파트로 분류하고, 2009년 4월 한 달 동안 현재 근무 중인 방사선사 23명을 대상으로 근무 부서를 직접 방문하여 유해 요인을 평가하였다. 평가에 사용한 도구는 원진 노동환경건강연구소의 "VDT작업에 관한 체크리스트"를 적용하였고 VDT 작업 조건, 업무 책상의 조건, 의자의 조건, 키보드의 조건, 모니터의 조건, 작업 자세, 보건 관리 특성, 기타 작업 환경의 8개 부문, 총 55개 항목을 통하여 현장 조사 및 평가하였으며 이에 대한 분석 결과는 한림대학교 성심병원 산업의학과에서 검증하였다. 서울대학교병원 핵의학과의 VDT 작업 조건은 비교적 양호한 수준이었다. 책상의 경우 최근 도입한 경우에는 인체공학적 설계로 사용자에게 적합하였으나 기존 책상의 15%는 기준치에 미달하였다. 의자의 경우는 기준에 적합하였지만 노후화로 인하여 적정 기능을 상실한 것이 5%였다. 키보드는 98%가 기준에 적합하였고 모니터는 화면의 각도 조절은 모두 가능하였지만 위치 조절이 불가능한 것이 38%로 조사되었다. 작업 자세의 경우 부적절한 자세로 장시간 노출되는 경우가 10%였으며 일부 항목에서 기준에 적합하지 않은 것으로 조사되었다. 보건 관리 측면에서도 개선의 여지가 있는 것으로 나타났다. 또한 조명과 온도, 소음, 환기 등 기타 작업 환경은 일부 항목에서 문제점이 발견되었지만 권고치를 충족하였다. 핵의학과 업무는 과거에 비하여 육체적인 업무는 줄었으나, 장시간 정적인 자세로 고도의 정밀도와 집중력을 요구하게 되었으며 이는 필연적으로 VDT 증후군을 유발하는 계기가 되었다. VDT 증후군은 앞으로도 지속적으로 발생할 가능성이 높으며 개선에 대한 경제적 비용이 상당하다는 점과 다양한 발병 요인을 내재하며 본인도 모르는 사이에 발생한다는 점에서 보다 구체적이며 효율적인 관리 체계가 필요할 것으로 판단된다. 핵의학과의 VDT 증후군은 인체공학적 사무 환경의 개선, 업무 절차(procedure)의 개선과 업무의 효율화, 직원간의 협동작업(teamwork) 그리고 규칙적인 운동, 꾸준한 스트레칭 체조와 같은 사용자 스스로의 노력, 지속적인 관심과 작은 노력으로 충분히 개선될 수 있으며 적극적으로 예방할 수 있을 것으로 사료된다. 이것은 쾌적한 업무 환경속에서 사용자의 육체적, 정신적 상태를 최상으로 이끌고 업무 효율성의 증대와 함께 내부 고객 만족도 상승으로 이어질수 있을 것으로 판단된다.

• 수산해양기술연구
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• 제20권1호
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• pp.49-59
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• 1984

선박용 강판(KR Grade A-1, SWS41A, SWS41B)의 수중용접 최적화에 관한 연구결과를 요약하면 다음과 같다. 1. 국산 라임티타니아계 용접봉 피복제의 흡수속도는 약 60분에서 일정하게 되고, 침수시간 8분까지의 흡수속도는 약 0.15%/min 였으므로 40cm 용접기간중의 정미 흡수량은 약 0.22%미만에 불과하였다. 2. 위의 이유와 건조, 직접, 침수용접봉에 의한 대기중, 수상, 수중용접과 모재의 인장강도 및 미시조직 비교실험결과에 의하면, 수중용접시간이 8분이내의 충분히 짧은 때에는 강도상 건조된 직접용접봉의 사용이 가능할 것이다. 3. 용접조건이 수중용접비이드에 미치는 영향을 KR Grade A-1강판에 대하여 조사한 결과, 용접각도는 60$^{\circ}$, 용접전류는 160A정도, 용접봉지름은 4mm인 경우가 적합하며, 또한 비이드외관과 X-선검사에 의하면 일미나이트, 라임티타니아, 고산화티탄계 용접봉이 가장 적합하였다. 4. 위의 용접봉 종류와 각 지름에 대해 비이드외 관검사에 의한 적정 수중용접전류의 범위는 어느 일정 범위내에 제한되며, 용접봉지름의 증가에 따라 전류는 증가하는 경향이다. 5. 수중용접부의 용착금속부에 관한 기계적특성조사에 의하면, 인장강도와 항복강도는 입열량과 이차함수적 관계가 성립되고, 이음효율이 100% 이상의 범위가 존재하며, 충격치와 스트레인은 모재의 경우보다 낮으나 그 증가현상이 고입열량 범위에서 존재하므로, SWS41A에 대한 수중용접 최적입열량범위는 약 13~15KJ/cm이다. 한편, 인장-인장 편진 피로한도가 모재의 경우보다 높고, 충격치와 연신율을 고려하여 구한 최적입열량의 범위는 약 16~19KJ/cm로서, 피로강도를 높이기 위한 입열량은 정적 인장강도때보다 고입열량으로 수중용접해야 한다. 이때 모든 실험식의 신뢰성은 95%수준이다. 6. 수중용접부에 대한 X-선검사와 미시조직검사 및 경도분포조사에 의하면 용접결함은 발견되지 않았으며, 특히, 깊이 1mm 표층부의 모재측 열영향부와 본드(bond)와의 경계부근에 경도 Hv400 max으로서 미세 마르텐사이트, 베이나이트, 퍼얼라이트와 소량의 조대한 입계페라이트 조직이며 그 외의 부위는 퍼얼라이트와 페라이트 조직으로서, 수소취성영향의 극심한 경도증가 및 조직은 발견되지 않았다. 7. 위에서 구한 입열량의 최적범위 내에서의 제어에 의하여 수중용접 할 경우, 신뢰성 있는 용접품질의 최적화가 가능할 것이다.

• 대한정형외과스포츠의학회지
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• 제10권1호
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• pp.27-34
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• 2011

목적: 자가 슬괵건을 이용한 전방 십자 인대 재건술에서 Cross pin 및 Graft Tensioner를 이용한 수술의 단기 추시 결과를 보고하고 조기 경험에서 발견된 수술 술기상의 문제점과 그 해결방안을 모색하고자 한다. 대상 및 방법: 2008년 1월부터 2009년 3월까지 자가 슬괵건을 이용한 전방 십자인대 재건술 후 최소 18개월이상 추시가 가능하였던 35예를 대상으로 하였다. 이식건의 대퇴골측 고정을 위해 Cross pin을, 경골측의 고정을 위해 Intrafix와 Post-tie를 사용하였다. 이식건은 Graft Tensioner을 이용하여 80N의 힘으로 고정하였다. 결과는 임상적, 방사선학적 결과와 합병증으로 평가하였다. 결과: IKDC 주관적 점수 및 Lysholm 점수는 술 후 89.1점 및 91.4점로 호전되었으며 축이동 검사 및 One-leg hop 검사도 술후 양호한 소견을 보였다. KT-1000 관절계 검사 및 Telos 부하 방사선 검사상 최종 추시시 건측에 비해 평균 $2.8{\pm}1.6$ mm, $2.6{\pm}1.3$ mm로 호전을 보였으며 대퇴골 터널은 평균 $2.3{\pm}1.1$ mm로 확장되었다. 수술 술기상 문제점으로 대퇴골 터널과 횡고정 터널의 불일치, 대퇴골 터널과 Graft Harness의 길이 불일치 그리고 연부 조직 자극이 관찰되었다. 결론: Cross pin 및 Graft Tensioner를 이용한 전방 십자인대 재건술은 단기 추시 상 좋은 안정성을 보여주는 수술 방법 중의 하나로 사료된다. 그러나 술기상 문제로 대퇴 터널-cross pin 불일치를 줄이기 위해 대퇴 터널을 짧게 만들거나 cross pin 터널을 피질골에 가능한 수직으로 만들어야 하며 대퇴 터널 형성시 위치 막대를 3 mm가량 더 진행시켜야 대퇴 터널-graft harness 불일치를 줄일 수 있을 것으로 생각된다.

• 한국수산과학회지
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• 제34권6호
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• pp.643-651
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• 2001

축제식 양식장에서 수차에 의한 순환효과를 재현하기 위해 수치모형을 개발하였다. 수치모형의 지배방정식으로는 2차원 수심적분 Reynolds 방정식을 사용하였고, 수차에 의한 가속도는 축력을 수차날개에 의해 밀려가는 유체의 질량으로 나눈 값으로 산정하였다. 수치모형을 적용하여 1대의 수차를 작동하고서 수차로부터 직선방향 loin 간격으로 관측된 유속자료와 비교하였다. 모형의 보정을 위해 유량보정계수와 무차원 와점성계수의 민감도를 실험하였다. 유량보정계수는 본 연구에서 처음 제시된 항으로 실험결과 15와 20에서 모형의 결과가 관측값과 가장 유사하였다. 유량보정 계수는 관측자료가 없거나 관측이 용이하지 않을 경우 효과적으로 사용할 수 있으며, 특히 수치실험에서 수차에 의해 발생하는 복잡한 수리특성을 비교적 단순하게 처리할 수 있다는 장점이 있다. Reynolds 응력을 Boussinesq 근사로 표현하는 녈 연구에 서 무차원 와점성계수는 6이 가장 적당한 것으로 계산되었다. 바람에 의한 전단효과를 파악하기 위해 유향 $0^{\circ}C,\;90^{\circ}C,\;180^{\circ}C$ 그리고 풍속 0, 2.5, 5와 7.5m/s 조건의 경우를 비교하였다. 풍향이 수차에 의한 제트류 방향과 평행하거나 정반대일 경우 유속변화는$1\%$ 이하이나, 제트류에 직각으로 향할 경우 제트류 좌우의 와류는 풍향에 따라 위치가 뚜렷이 바뀌며, 유속은 약 $4\%$까지 감소하는 것으로 나타났다. 유속변화 $4\%$는 바람응력 외에 호지의 기하학적 평면구조 혹은 변장비 등에 따른 효과도 포함하는 것으로 생각되었다. 호지에 미치는 바람에 의한 유속변화가 $4\%$ 이하인 것으로 보아, 바람웅력의 영향은 매우 미약한 것으로 나타났다. 그러나 호지의 기하학적 특성과 관련한 와류형성 기구에 대해서 바람이 미치는 효과는 무시할 수 없는 것으로 생각되었다. 모형은 또한 축제식 양식장 2곳에 적용하였다. 양식장 호지 A와B는 각기 변장비 1.05와 0.68, 면적 1.02ha와 0.66ha 그리고 평균수심 1.2m를 갖는다. 각각의 호지에 수차 4대를 작동하고서 관측된 유속과 수치모형을 적용한 계산결과를 회귀 해석하였다. 호지A에서 유향 및 유속의 상관계수는 각기 0.8928, 0.6782이며 호지 B의 경우 각기 0.8539, 0.7071인 것으로 나타났다 따라서 본 연구에서 사용된 모형은 호지의 순환특성을 비교적 잘 재현하였으며, 향후 수차운영과 양식호지의 수질관리에 관한 유용한 도구로 사용될 수 있을 것으로 생각하였다.

• Journal of the Korean Wood Science and Technology
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• 제2권2호
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• pp.8-12
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• 1974

한국의 목재 인공 건조법을 개발하기 위하여 필자의 전직 대학인 전북대학교 전 김두헌 총장님, 동농대전 백남혁학장 및 동농대교수 제위의 각별한 협조를 얻어 1956년 고액을 지불하고 미국 More Dry Kiln Co.에서 최신의 목재 인공 건조 장치를 도입하여 전북 농대 임학과에 설치하게된 것이다. 그러나 이 건조 시설을 활용하는데는 많은 지장이 있었으므로 1959년 전기 More Dry Kiln의 온, 습도 조절장치만을 이용한 소형 Dry kiln을 제작하여 본 시험을 실시한 것이다. 공시수종은 소나무, 낙엽송, 은행나무, 전나무, 밤나무 및 감나무등이며, 공시목의 크기는 것이 60cm, 넓이 10cm 및 두께 15-35mm이다. 실험한 건조 조건은 건조 온도를 일정히 ($170^{\circ}F$)하고, 관계습도를 각종으로 변화할때 얻어지는 건조 속도를 측정하는 동시에 각 건조조건에 의하여 유발되는 건조결함을 조사하여 공시목의 초기 함수율과 건조 최경함수율 특히 shell의 함수율과의 비가 이들의 결함 형성 특히 표면경화(casehardening) 형성에 미치는 영향을 구명하였으며 또한 casehardening 계산식을 유도하였다. 1. 목재내부에 형성된 응력 즉 prong이 개주할 때의 응력은 prong이 서로 접합할 때의 응력을 100으로 하는 백분율에 의하여 다음식으로 표시할 수 있다. 단, 응력 측정에 사용한 prong은 그림 1과 같이 작성하여야 한다. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ 상식은 다음과 같은 간이식을 사용할 수 있다. $CH=\frac{A-B'}{A}{\times}200%$ 2. 일정 한 건조 조건하에 건조하여 항중에 달하고, 또한 normal casehardening을 형성하는 경우에 는, 그 sample board의 shell 의 함수율은 특히 얇은 sample board에 있어서 US Dep. Agr., Forest Products Laboratory에서 발표한 EMC 보다 낮다. 3. 본 실험에서 측정한 1시간당 목재 건조 표면적 $1cm^2$ 당 증발하는 증발량 즉 건조속도를 비교 검토한 결과 다음과 같은 순위로 되었으며, 비교 검토한 5수 종중 최대치를 유하는 은행나무 MC 20% 에 있어서 최저치를 표시한 밤나무의 3.8배가 된다. (표 1 참조) (1) 은행나무 (2) 감나무 (3) 소나무 (4) 낙엽송 (5) 밤나무 특히 함수율 26% 이하에 있어서 각 함수율에 대한 증발속도치는 다음과 같은 일차식으로 표시 할 수 있으며, 그 회귀계수 유의성 검정에 있어서의 T치는 다음과 같이 각각 고율의 유의성을 표시하였다. (표2 참조) 상기중 Y는 증발속도($g/cm^2hr$.), X는 함수율을 각각표시한다. 이들 회귀직선을 도시하면 그림 2와 같다. 4. 초기함수율과 건조 최종기에 있어서의 목재의 표층 함수율 즉 shell의 함수율과의 비(SR)가 casehar dening 형성에 미치는 영향은 다음과 같다. 어떤 SR 값에 관하여 그 SR 값 이하를 유하는 총개제수(N) 중 CH 제4급이 출현하는 수(D)의 확율 즉 N에 대한 D의 출현확율 P%는 표 3과 같다. (D의 출현확율 P%를 위험확율이라고 가칭한다.) 표 4에 있어서 종란의 1,2,3의 숫자는 각각 다음과 같은 사항을 표시한다. (1) CH 값 제 4급이 출현하지 아니 하는 안전한 최소 SF 값 (2) 위험을 30%를 허용하는 경우에 있어서의 SF 값의 한계 (3) CH 값 제 4급 이하가 발생하지 아니하는 위험율 100%의 값의 범위 상기한 실측 결과에 의하여 밤나무, 낙엽송등은 내부응력 형성이 용이한데 비하여 감나무, 소나무등은 내부응력 형성이 용이하지 아니하여, 특히 전나무, 은행나무등은 타수종과 동일한 건조조건에 있어서 reverse casehardening을 초래함에 비추워 타수종에 비하여 현저히 내부응력 특히 normal casehardening이 잘 형성되지 아니한다는 것을 알 수 있다. 5. casehardening을 제외한 각종의 drying defects는 long time loading에 있어서 그 내부응력이 ultimate stress를 초과할 때 나타나는 것인데 건조조건 온도 $170^{\circ}F$에 대하여 습도를 낮게하여도 그렇게 심하지 아니하나, 온도 $200^{\circ}CF$의 저습에 있어서 end coating을 하지 아니하는 경우에는 용이하게 발생한다. 특히 밤나무는 실험한 타수종에 비하여 casehardening 및 활열성 defects가 강한 것을 지적할 수 있다.

• 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.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2001년도 제17차 공동학술강연회 및 춘계학술답사
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• pp.42-63
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• 2001

무령왕릉의 보존대책을 수립하기 위하여 누수 현상, 고분구조 벽체거동 상황 및 구조안전점검, 고분 내에 서식하는 조류의 제거, 고분내 습기 및 결로현상 제거를 위한 공기조화시설 등을 포함하는 종합 정밀저사를 1996년 5월 1일 부터 1997년 4월 30일 까지 1년간 수행하였다. 이러한 연구를 수행하기 위하여 기초 지반에 대한 정밀측량, 고분 내외부의 년중 온습도 모니터링, 지반의 내부물성 파악을 위한 지구물리 탐사, 시추 자료에 대한 각종 물성실험, 지반의 투수계수 측정 및 지구화학적 분석을 실시하였다. 고분 내외부에 대한 정밀측량 결과 봉분 중심의 현실 중심보다 북동쪽으로 5m 이격되어 있다. 무령왕릉의 경우는 발굴 당시에도 유사한 분포를 하였으나, 이로 인하여 불균형적인 토압을 발생시키는 원인이 되고 있다. 벽돌깨짐 상황 조사결과 무령왕릉의 조사 대상 벽돌 6025장중 1972년에는 435장 파손되었던 것이 1996년 조사결과 1072장이 파손된 것으로 밝혀져 파손율이 2.5배로 증가하였다. 6호분의 경우는 이보다 더 심하여 벽돌 파손율이 2.9배로 증가하고 있다. 1972년 상황은 약 1450년간 진행된 것이고 1996년의 상황은 불과 24년간 진행된 것임을 감안할 고분이 발굴된 이후 벽돌의 균열은 상당한 가속도로 진행되어 온것이 사실이며 이대로 진행된다면 더욱 더 가속화될 것으로 판단된다. 고분벽체의 거동상태를 계측한 결과 무령왕릉 동측벽의 경우 우기와 건기에 각각 2.95 mm/myr및 1.52 mm/myr의 거동을 보여 우기에 지하수 유입에 의한 지반의 약화로 인하여 건기보다 2배정도 거동하는 양상을 보인다. 한편, 연도 입구의 호벽은 건기에 전실쪽으로 0.43 mm/myr, 연도쪽으로 2.05 mm/myr의 거동을 보여 무령왕릉에서는 가장 심한 거동을 보이고 있다. 6호분의 거동현황은 건기에만 측정된 바, 현실의 동측벽과 서측벽이 각각 벽체 뒤쪽으로 7.44 mm/myr, 현실안쪽으로 3.61 mm/myr의 거동을 보여 조사대상 5호분, 6호분, 7호분, 중 가장 심한 거동을 보이고 있다. 이는 고분 벽돌의 깨짐이 6호분이 가장 심하다는 사실과 무관하지 않은 것으로 판단된다. 봉분내부의 토양층구조에 대한 지오레이다 영상단면을 분석한 결과 무령왕릉 연도상부의 누수지방지층이 심하게 균열되어 있음을 발견하였다. 이 곳은 고분내부로 직접누수가 발생하는 곳이다. 직접누수와 지하수 형태로 유입된 침투수는 고분군 주위의 지반의 함수비를 증가시켜 지반의 지지력을 약화시키고 또한 고분내로 서서히 유입되어 고분내부의 습도를 100%로 유지시키는 주된 원인이다. 이러한 높은 습도는 고분내의 남조류의 번식을 가져왔으며 남조류의 번식은 현재 6호분이 가장 심각하고 7호분이 우려되는 수준이며 5호분은 문제가 없는 것으로 판단된다. 이와 같이 고분군의 발굴후 인위적인 환경변화와 지속적인 강우침투 및 배수 불량의 영향은 고분군의 안정성에 상당한 위험을 초래하였으며, 현 상태는 각 고분에 대한 보강이 불가피한 것으로 판단된다. 고분 벽돌의 깨짐, 고분 벽체의 거동, 조류의 서식등을 포함하여 송산리 고분군에서 발생되고 있는 보존상의 제반 문제점들을 일차적으로 누수 및 침투수에 의한 결과이다. 그러므로 무엇보다도 고분군 내부 및 고분 주변으로의 강우 및 지하수 침투를 막는 차수 대책이 시급한 것으로 판단된다. 또한 이미 발생한 변위가 더 이상 진행되지 않도록 하중을 경감하고 토압의 균형을 이루는 보강대책이 시급한 실정이다. 고분군의 보존대책으로는 고분의 구조안전에 관하여 근본적인 구조변경이 불가피한 직접 보강대책보다 간접적인 보강대책이 바람직한 것으로 판단된다. 간접적 보강대책으로서는 현 봉분규모의 축소, 불균등토압의 조정, 강우침투 방지를 위한 최종복토시스템, 유도배수구의 설치 및 능선 상부로부터의 지하수 차단시설을 포함한다. 이러한 차수대책은 고분군의 제문제를 해결하는 가장 근본적인 대책이라 할 수 있다. 고분내 결로현상 및 습기 제거를 위하여 항온항습장치를 전실에 설치하고 덕트를 통하여 고분내 현실로 순환시키는 방법을 제안하며 외부 온도의 영향을 덜 받게 하기 위하여 전실상부 토양을 현재보다 두껍게 하고 전실의 천정마감재를 열전도도가 낮은 목재로 교체하며 출입문의 이동등을 제안하였다. 금번 조사 연구를 통하여 얻어진 각종 보수 및 보존대책은 고분구조 자체에 가능한 한 최소의 변화를 주면서 가장 시급한 문제점부터 해결하도록 제시되었다. 설계 및 시공단계에서는 보수의 경중을 가려 순서에 입각하여 이루어져야만 하며 설계 및 시공단계에서 고분의 구조안전에 영향을 주지 않도록 각별한 주의가 요망된다. 끝으로, 상기의 보수대책이 실시된 후 이에 대한 평가 및 향후의 영구 보존을 위한 벽체경사 계측, 함수비 및 지하수위 계측, 온습도 측정 등을 포함하는 사후계측시스템은 필수적이라 할 수 있다. 각종 계측자료를 이용한 장기적이고도 세심한 분석을 통하여 완벽한 보존 관리가 이루어져야할 것으로 사료된다.로 사료된다.

• 사상체질의학회지
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• 제11권2호
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• pp.119-150
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• 1999

동(東) 서양의학(西洋醫學)이 여러 방면(方面)으로 눈부시게 발전(發展)해 왔음에도 불구(不拘)하고 동일질병(同一疾病)에 대한 약(藥) 효과(效果)의 개인별(個人別) 차이(差異)나 질병(疾病)에 대한 개인별(個人別) 감수성(感受性)의 차이(差異)에 따른 여러 가지 면역관계(免疫關係) 질환(疾患)의 다양성(多樣性)이나 난치병(難治病)의 다양(多樣)한 예후(豫後) 등(等)의 이유(理由)를 정확(正確)히 이해(理解)하지 못하고 따라서 적절(適切)한 대처(對處)를 하지 못하고 있는 것이 현실(現實)이다. 그런데 사상의학(四象醫學)의 네 체질(體質)에 따른 질병(疾病) 관리(管理), 치료(治療) 및 예방법(豫防法)은 현대(現代)의 난치병(難治病)이라고 할 수 있는 성인병(成人病), 면역계(免疫係) 질환(疾患), 스트레스성(性) 질환(疾患)의 관리(管理)에 효과적(效果的)으로 적용(適用)할 수 있으므로 현재(現在) 한방임상의학(韓方臨床醫學)에서 많이 응용(應用)되고 있다. 이러한 사상의학(四象醫學)을 세계(世界)에 폭넓게 적용하기 위해서는 국제적(國際的)으로 응용(應用)할 수 있는 체질진단(體質診斷)의 기준(基準)이 마련되어야 한다. 우선(于先) 본(本) 연구(硏究)는 외국인(外國人)에게도 과연(果然) 체질(體質)이 존재(存在)할까 하는 의문점(疑問点)을 해결(解決)하기 위(爲)하여 미국인(美國人)을 대상(對象)으로 체질(體質) 분류(分類)를 시도하여 체질(體質) 존재(存在) 여부(與否)를 확인(確認)하는 작업(作業)부터 시작(始作)하였다. 또 체질(體質)이 존재(存在)한다면 체질(體質) 진단(診斷) 도구(道具)로는 어떤 것이 좋을까를 알아보기 위(爲)한 연구(硏究)를 병행(竝行)하였다. 선택(選擇)된 체질(體質) 진단(診斷) 도구(道具)로는 경희대학교(慶熙大學校) 사상의학(四象醫學) 교실(敎室)에서 개발(開發)되어 학회(學會)에서 공인후(公認後) 임상(臨床)에서 널리 사용(使用)되는 체질(體質) 진단(診斷) 도구(道具)인 QSCCII를 바탕으로 이를 영문(英文)으로 번역(飜譯)하고 채점(採點) 방법(方法)을 보완(補完)하여 새롭게 제작(製作)된 new QSCCII + 사용(使用)하였다. 본(本) 연구(硏究)는 국내(國內)에서 표준화(標準化)되어 사용(使用)하고 있는 체질진단진단도구(體質診斷診斷道具)인 QSCCII를 보완하여 미국(美國)에서 응용(應用)할 수 있는 새로운 진단(診斷) 도구(道具)를 마련하고자 처음으로 시도(試圖)된 연구(硏究)이다. 조사(調査) 대상(對象)은 University of Bridgeport. Connecticut. U.S.A의 학생(學生), 교직원(敎職員)그리고 Health Science Center의 Clinic을 방문(訪問)한 사람중(中) 본(本) 조사(調査)에 협력(協力)한 사람이 주(主)로 그 대상(對象)이 되었으며 기타(其他) 주변(周邊)의 현지인(現地人)들이 대상(對象)이 되었다. 년(年) 조사대상인원(調査對象人員) 344명(名)이었고 전체(全體) 조사(調査) 대상(對象)에서 재검사(再檢査)를 할 수 있었던 인원(人員)은 240명(名)이었다. 연구기간(硏究期間)은 1998년(年) 9월(月)부터 1999년(年) 8월(月)까지 약(約) 1년(年) 여(餘)에 걸쳐 실시(實施)되었다. 이러한 연구결과(硏究結果)를 고찰(考察)해 볼 때 아래와 같은 결론(結論)을 얻었다. 1. 미국(美國) 사람에게도 사상체질(四象體質)은 존재(存在)한다. 추론(推論)컨데 미국(美國)에는 다양(多樣)한 인종(人種)이 섞여 살고 있으므로 외국인(外國人) 모두에게 역시(亦是) 체질(體質)이 존재(存在)한다고 볼 수 있다. 2. 미국인(美國人)에게 특(特)히 백인(白人)에게선 소양인(少陽人)으로 진단(診斷)되는 경향(傾向)이 높았다. 이 결과(結果)는 미국(美國)사람에게도 사상체질(四象體質)은 존재(存在)한다는 가설(假說)과 다소(多少) 부합(附合)된다 사료(思料)된다. 3. 검사재검사(檢査再檢査)를 통하여 분석(分析)된 결과(結果)를 볼 때 그 결과(結果)가 일관(一貫)되게 나오는 것으로 보아 new QSCCII +가 외국인(外國人)의 체질(體質)을 진단(診斷)할 때 일관(一貫)된 결과(結果)를 얻을 수 있는 진단방법(診斷方法)일 가능성(可能性)을 시사(示唆)한다. 4. 표준(標準) 집단(集團)의 체질(體質) 분류(分類)에서는 인종(人種)에 관계(關係)없이 체질(體質)이 존재(存在)하고 있었다. 5. 반응(反應) 빈도(頻度)가 낮은 문항(問項)은 미국인(美國人)을 위(爲)한 표준화(標準化) 연구(硏究)를 할 때 미국인(美國人)에게 이해(理解)가 될 수 있는 또다른 표현(表現)으로 바꾸어 적용(適用)해 볼 필요(必要)가 있을 것으로 추정(推定)된다. 6. 미국인(美國人)의 체질(體質)을 정확(正確)하게 하기 위(爲)해서는 표준화(標準化) 작업(作業)을 함으로써 QSCCII라는 진단도구(診斷道具)를 이용(利用)하여 측정(測定) 진단(診斷) 데이터를 평가(評價)할 수 있는 진단(診斷) 기준(基準)이 만들어져야 한다. 7. 체질(體質)이 불투명(不透明)하다고 나온 71명(名) 중(中)에는 잠재적(潛在的) 태양인체질(太陽人體質)이 포함(包含)되어 있을 것으로 추정(推程)되나 태양인(太陽人)의 희소성(稀少性)에서 기인(起因)하는 new QSCCII+의 변별력저하(辨別力低下)에 대한 해결방안(解決方案)에 대(對)한 연구(硏究)가 추후(追後)에 진행(進行)되어야 할 것으로 사료(思料)된다. 8. 연구결과(硏究結果) 북미지역(北美地域)의 체질분포(體質分布)는 다음과 같다. 연인원(年人員)을 대상(對象)으로한 분포(分布)에서는 소양인(少陽人) 36.25 %(87명), 태음인(太陰人) 13.75 %(33명(名)), 소음인(少陰人) 20.41%(49 명(名)), 분류(分類)가 안되거나 태양인(太陽人)인 경우(境遇)가 29.58%(71 명(名))이었다.