• Tuberculosis and Respiratory Diseases
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• 제53권4호
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• pp.409-419
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• 2002

연구배경 : 급성폐손상에서 표면활성물질의 치료효과는 허탈된 폐포를 재환기시키는 작용 외에 표면활성물질이 지닌 항염증효과도 기여하는 것으로 알려져있다. 표면활성물질의 항염증효과의 기전에 호중구의 아포토시스를 촉진하는 작용이 관련되어 있을 가능성이 있다. 본 연구에서는 사람의 말초혈액 호중구와 LPS로 급성폐손상을 유발한 흰쥐의 폐포내 호중구의 아포토시스에 대하여 표면활성물질이 미치는 영향을 평가하고자 하였다. 방 법 : 생체외 실험에서는 자원자의 혈액에서 호중구를 분리하여 같은 수의 호중구 ($1{\times}10^6$)에 LPS(10, 100, 1000ng/ml), surfactant(10, 100, 1000${\mu}g$/ml), 그리고 LPS(1000ng/ml)와 표면활성물질(10, 100, 1000${\mu}g$/ml)을 혼합하여 투여하였다. 24 시간 배양한 후에 호중구의 아포토시스를 Annexin V 방법을 이용하여 분석하였다. 생체내 실험에서는 백서의 기관 내로 LPS(5mg/kg)를 투여하여 급성폐손상을 유발한 후에, 한 군은 표면활성물질(30mg/kg)을 다른 군은 생리식염수(5ml/kg)를 30 분 후에 기관 내로 투여하였다. LPS 투여 24 시간 후에 기관지폐포세척술을 시행하여 기관지폐포세척액을 얻었으며, 여기에서 호중구를 분리하여 Annexin V 방법으로 아포토시스를 측정하였다. 또한 LPS 투여 전과 23 시간 후에 one chamber body plethy smography를 이용하여 호흡역학(일호흡량, 호흡수, Penh)의 변화를 측정하였다. 결 과 : 생체외 실험에서 LPS 투여는 사람 말초혈액 호중구의 아포토시스를 억제하였다(대조군; $47.4{\pm}5.0%$, LPS 10ng/ml; $30{\pm}10.9%$, LPS 100ng/ml; $27.5{\pm}9.5%$, LPS 1000ng/ml; $24.4{\pm}7.7%$). 낮은 농도의 표면활성물질 투여는 LPS 투여에 의해 억제 되었던 호중구의 아포토시스를 촉진시켰다(LPS 1000ng/ml=Surf 10${\mu}g$/ml 1; $36.6{\pm}11.3%$, LPS 1000ng/ml+Surf 100${\mu}g$/ml 1; $41.3{\pm}11.2%$). 높은 농도의 표면활성물질($1,000{\mu}g/ml$) 투여는 그 자체도 호중구의 아포토시스를 억제할 뿐만 아니라($24.4{\pm}7.7%$) LPS의 항아포토시스 작용을 촉진하였다(LPS 1000ng/ml+Surf $1000{\mu}g/ml$; $19.8{\pm}5.4%$). 생체내 실혐에서 표면활성물질 투여는 생리식염수 투여에 비해서 급성폐손상을 받은 쥐에서 기관지 폐포세척액의 호중구의 아포토시스를 촉진하였다($6.03{\pm}3.36%$ vs $2.95{\pm}0.58%$). 표면활성물질을 투여한 백서는 생리식염수를 투여한 백서에 비해 LPS 자극 후 23 시간에 측정한 기도저항(Penh) 이 낮았다($2.64{\pm}0.69$ vs $4.51{\pm}2.24$, p<0.05). 결 론 : 이상의 결과로 표면활성은 사람의 말초혈액 호중구와 급성폐손상을 받은 백서의 기관지폐포세척액 내의 호중구의 아포토시스를 촉진하며, 이런 효과가 표면활성불질의 항염증효과의 기전 중 하나일 것으로 추측된다.

• 한국의학물리학회지:의학물리
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• 제18권2호
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• pp.81-86
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• 2007

영상유도 방사선치료의 대표적 방법의 하나로 선형가속기에 부착된 on-board imager (OBI) 영상장치를 사용하여 획득한 cone-beam CT (CBCT) 영상이 정밀 방사선치료 시 환자 정렬 오류를 보정하는데 활용되고 있다. 본 연구에서는 CBCT 영상 획득 시 환자 호흡에 의한 영상 품질과 정보의 변화를 분석하고자 호흡 움직임을 모사할 수 있는 팬텀과 CBCT 영상획득용 팬텀을 제작하고, 여러 움직임 조건에서 획득한 CBCT 영상들과 정지상태에서 얻은 CBCT 영상과의 비교, 분석을 수행하였다. 분석대상 움직임 조건을 구성하는 요소로서 움직임 주기는 5가지(2초, 3초, 4초, 5초, 6초)를 선정하였고, 움직임 변위 크기는 4가지(0.7 cm, 1.6 cm, 2.4 cm, 3.1 cm)를 선정하여 총 20가지의 움직임 조건에서 CBCT 영상을 획득하였다. CBCT 영상의 CT값의 상대적 크기로 비교한 영상 화소 값 강도의 평균 변화는 정지 상태의 영상과 비교하여 변위가 0.7 cm의 경우 71.07%, 1.6 cm의 경우 48.88%, 2.4 cm의 경우 30.60%, 3.1 cm의 경우 17.38% 값을 보였고, 팬텀 움직임 방향의 영상 길이는 정지상태에서 2.1 cm, 움직임 변위가 0.7 cm의 경우 2.66 cm, 1.6 cm의 경우 3.06 cm, 2.4 cm의 경우 3.62 cm, 3.1 cm의 경우 4.04 cm 값을 보여 움직임 변위 크기가 클수록 영상 품질 저하와 형태적 정보의 왜곡정도도 증가하였다. 움직임 주기에 의한 영상품질의 변화는 움직임 변위 크기가 작은 경우를 제외하고는 특별한 영향이 없었다. 본 연구를 통해 환자 호흡에 의한 움직임 변위가 큰 부위의 CBCT 영상을 획득할 때, 영상 품질과 정보에 변화가 발생할 수 있어 이 점을 고려하여 임상에 사용해야 하며, 궁극적으로 호흡 신호와 연동된 CBCT 영상이 필요함을 확인할 수 있었다.로버 + 혼파초지에 비하여 낮은 결과를 보였다(p<0.05). 2년 평균 CPDM 수량은 레드 클로버 + 혼파초지가 2,832kg으로 관행 혼파초지(2,372kg)나 잔디형 초종 + 혼파초지(2,266kg)에 비하여 높은 결과를 나타내었다(p<0.05). 2년 평균 DDM 수량은 레드 클로버 + 혼파초지가 8,881kg으로 관행 혼파초지(8,255kg)나 잔디형 초종 + 혼파초지(7,314kg)에 비하여 높은 결과를 얻었다(p<0.05). 2005년 5회 예취시의 식생비율은 관행 혼파초지는 orchardgrass는 45%, tall fescue 22%, Kentucky bluegrass 5% 및 white clover 24%이었으며, 레드 클로버 + 혼파초지는 orchardgrass 40%, tall fescue 22%, Kentucky bluegrass 4% 및 red clover 31%이었고, 잔디형 초종 + 혼파 초지는 orchardgrass 37%, 잔디형 초종 37%(tall fescue 23%, Kentucky bluegrass 6%, perennial ryegrass 8%) 및 white clover 23%를 유지하였다. 이상의 결과를 종합할 때, 초종과 파종비율에 따른 혼파초지의 건물수량과 사료가치의 차이를 확인할 수 있었으며, 레드 클로버 + 혼파 초지가 건물수량과 사료가치를 높이는데 효과적이었다.\ell}$ 이었으며 , yeast extract 첨가(添加)하여 배양시(培養時)는 yeast extract 농도(濃度)가 증가(增加)함에 따라 단백질(蛋白質) 함량(含量)도 증가(增加)하였다. 7. CHS-13 균주(菌株)의 RNA 함량(含量)은 $4.92{\times}10^{-2 }\;mg/m{\ell}$이었으며 yeast extract 농도(濃度)가 증가(增加)함에 따라 증가(增加)하다가 농도(濃度) 0.2%에서 최대함량(最大含量)을 나타내고

• Strategy21
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• 통권46호
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• pp.239-276
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• 2020

유엔 안전보장이사회(UNSC, United Nations Security Council) 주도의 경제제재는 초창기 '포괄적 경제제재(comprehensive sanctions)' 모델에서 '스마트 경제제재(smart sanctions)' 모델로 발전하고 있다. 유엔 안보리는 직접적인 무력개입(military intervention)보다 규범적 비용(normative costs)과 부담이 덜한 경제제재를 통해 대상 국가의 손익계산법(cost-benefit calculation)을 바꿔 행동변화를 이끌어내려고 했으나, '포괄적 경제제재'에 따른 비용 대부분이 일반 대중에게 전가되면서, 인도적 위기(humanitarian crisis) 사태를 초래하고, 대상 국가의 내부 결속력을 강화하는 역설적인 상황을 만들었다. 이에 따라 정책 결정 과정에 직접적으로 관여하는 지도자와 정치 엘리트를 대상으로 자산을 동결(asset freeze)하거나 여행금지(travel ban) 조치 등을 집중적으로 하는 '스마트 제재'가 탄생하였다. 대북한 경제제재 또한 '스마트 경제제재' 모델로 점차 발전하여 그 효과성을 나타내고 있다. 특히 최근의 결의안(resolutions)을 통해 석탄 수출을 전면 금지하고, 원유 수입을 제한함에 따라 지표상 가시적인 성과가 나타나고 있고, 2018년부터 한국, 미국과 평화협상에 나서면서 제재완화를 촉구하는 등, 위와 같은 '스마트' 대북제재가 북한의 행동변화를 이끌어내고 있음을 알 수 있다. 대북제재의 효과성은 북한의 대외무역규모(total trade volume) 변화량을 통해 측정할 수 있는데, '포괄적 경제제재'의 성격에 가까운 초기의 대북제재 결의안 채택 이후에는 북한 대외무역규모가 감소한 경우도 있지만 도리어 증대된 경우도 있었다. 그러나 석탄 수출 금지 및 원유 수입 제한 조치를 담은 2016, 2017년의 결의안 이후에는 북한 대외무역규모가 2016년 약 65억 달러에서 2017년 약 55억 달러로, 2018년에는 약 28억 달러로 대폭 감소한 사실을 발견할 수 있다. 북한의 대외무역은 정권의 자금줄과 같기 때문에 대외무역규모의 감소는 곧 '스마트 제재'의 효과와 같다. 대북경제제재의 효과성에 영향을 미치는 두 번째 조건은 중국의 대북제재 레짐(sanctions regime)에의 참여 여부다. 북한은 경제적으로 중국에 상당히 의존하고 있고, 이는 지표상으로도 명백히 나타나고 있다. 중국은 그 동안 북한의 지정학적인 가치 및 급변 사태 시 북-중 국경에서의 대규모 난민 발생 우려 등에 따라 직간접적으로 북한을 지지해왔지만, 북한 핵능력의 고도화에 따른 동북아시아 지역에서의 핵확산(nuclear proliferation) 우려, 미-중 무역분쟁에 따른 여파 등으로 대북제재 레짐에 성실히 참여할 것을 밝혔다. 실제로 중국의 대북한 석유 수출량이 감소하고, 북-중간 대외무역 총량 또한 2016년부터 지속적으로 감소하며, 대북경제제재에 중국의 참여가 제재 성공의 중요한 변수임을 증명했다. 효과적인 대북제재를 위한 마지막 요건은 북한의 경제제재 회피 노력 방지(prevention of North Korea's economic sanctions evasion efforts)다. 앞서 밝힌 바와 같이 석탄 수출과 원유 수입은 북한 정권의 자금줄이자 핵무력 고도화를 위한 필수 에너지원이다. 중국이 대북제재 레짐에의 참여를 선언한 상태에서 중국으로부터의 원유 수입량이 급감함에 따라 중동지역 등지로부터 바닷길을 통해 원유를 수입해야 하는데, 원유 수입량 제한에 따라 동중국해(East China Sea) 및 공해(high seas)상에서 선박 대 선박간 불법 환적(ship-to-ship illegal transshipment)을 실시하면서 대북제재를 무력화하고 있다. 유엔 대북제재위 산하 전문가 패널(Panel of Experts), 미 국무부(U.S. Department of State), 미 재무부 외부자산통제국(U.S. Department of the Treasury's Office of Foreign Assets Control, OFAC) 등은 보고서를 통해 북한의 해상 불법 환적 실태를 상세히 밝히고 있는데, 자동 선박 식별 장치(AIS, Automatic Identification System)의 허위 신호 송출(false signaling), 선박 등록 문서 위조(false certificate of registry)와 같은 방식으로 감시 및 단속을 회피하고 있는 실정이다. '스마트'한 대북제재 설계 및 중국의 참여로 대북제재가 북한의 행동 변화를 이끌어낼 수 있음이 확인되었지만, 국제사회의 눈을 피해 해상에서 만연하고 있는 불법 환적과 같은 행위는 효과적인 대북제재 실행의 마지막 퍼즐이라고 할 수 있다. 앞으로 해상에서의 불법 환적 행위를 막기 위해 다음 세 가지 정책적 함의를 도출해낼 수 있다. 첫 번째는 가장 강력한 조치라고 할 수 있는 해상봉쇄(maritime blockade)에 대한 고려다. 전세계 물동량의 40%가 지나가는 말라카 해협(Malacca Strait)은 북한에게도 중요한 해상 교통로이다. 북한이 계속해서 결의안을 위반하고 공해상에서 불법 환적 행위를 자행할 경우, 말라카 해협에서 북한과 연계된 의심 선박을 검문 검색하고 차단(interdiction)하여 강제적인 방식으로 북한의 제재 회피 노력을 근절할 수 있다. 남중국해(South China Sea)에서 중국과 미국 간, 중국과 주변국 간 갈등이 격화됨에 따라 다국적군의 말라카 해협 봉쇄는 중국에게 달갑지 않겠지만, 유엔 대북제재 결의안에 명시되어 있는 의심 선박에 대한 검문 검색 행위임을 명백히 함과 동시에 다자간의 협조를 바탕으로 하여 규범적 정당성(normative justification)을 높인다면 충분히 실현 가능한 방안이다. 두 번째는 공해상에서의 불법 해상 환적에 대한 감시 강화와 증거 수집이다. 마지막 세번째는 대한민국의 다국적 해상 감시 활동에의 참여다. 북한의 대북제재 이행 여부는 한국의 안보와 직결되는 사안이다. 대북제재의 최종 목표는 북한 비핵화에 있고, 협상 테이블에 북한을 이끌어내는 데 제재가 효과적이라는 것이 드러났기 때문에 핵 위협의 당사자인 대한민국 또한 효과적인 제재 이행 여부 감시에 책임감을 가져야 한다.

• 지능정보연구
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• 제20권3호
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• pp.93-108
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• 2014

기업 의사 결정 지원을 위하여 거래 데이터를 다양한 관점에서 분석하고 활용하려는 노력과 관심들이 증가하고 있다. 이러한 노력들은 고객 관리나 마케팅에만 국한되는 것이 아니라 부정행위에 대한 감시와 탐지를 목적으로도 다양한 분석 방안들이 연구되고 있다. 부정행위는 기술의 발전을 악용하여 다양한 형태로 진화하고 있으며, 이에 따라 목적에 맞는 부정탐지 방안 연구와 적용을 통하여 탐지 효용의 극대화를 위한 노력의 필요성이 증가하고 있다. 이러한 연구 동향의 일환으로 본 연구에서는 대용량 거래 데이터가 저장 관리되고 있는 국내 최대 농수산물 유통 시장의 2008년부터 2010년까지 상장예외품목의 거래 가격을 분석하여 부정 탐지 규칙을 도출하였으며, 전문가 검증을 통하여 도출 된 규칙의 신뢰성을 확보하였다. 본 연구의 주요 부정거래 분석 방안으로는 정상적인 데이터들은 발생 확률이 높은 반면에 특이한 데이터들의 발생 확률은 낮다고 가정하는 통계적 접근을 통한 이상치 식별 방안을 활용하였다. 이에 따라 부정거래 분석 별로 정의 된 Z-Score 값보다 클 경우 부정거래 탐지 대상이 된다. 다만 상장예외품목 거래의 경우 취급 가능한 중도매인의 수가 제한되어 있으며, 일반적인 상장품목의 거래보다 거래량이 적기 때문에 소수의 이상치가 품목의 평균에 미치는 영향이 크다. 그 예로 다른 소수의 중도매인들이 해당 품목을 정상적인 가격에 거래하였더라도, 특정한 중도매인 한 명이 지나치게 비정상적인 가격에 거래할 경우 모든 거래들이 부정거래로 탐지 될 가능성도 있다. 이러한 문제를 해결하기 위하여 기존의 Z-Score의 개념을 활용하여 수정된 Z-Score(Self-Eliminated Z-Score)를 사용하였다. 또한 부정 유형별 탐지 규칙 관리와 활용을 위한 시스템 프로토타입(prototype) 개발을 수행하였다. 이를 통하여 실제 부정거래 탐지 업무에 적용할 수 있는 효과적인 방안을 제시하였고, 농수산 유통시장의 공정성 및 투명성 확보를 위한 관리 감독의 기능 강화가 가능할 것이다.

• Radiation Oncology Journal
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• 제19권3호
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• pp.275-286
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• 2001

목적 : 세기조절방사선치료의 임상적용을 위한 정도보증 절차를 확립하고, 실제 치료환자 1례에 대한 적용 과정을 보고하고자 한다. 대상 및 방법 : 본원에서는 세기조절방사선치료를 시행하기 위해 역방향 치료계획(inverse planning) 시스템으로 $P^3IMRT$ (ADAC, 미국)와 다엽콜리메이터(Multileaf collimator, MLC)가 부착된 방사선치료용 선형가속기 Primus (Siemens, 미국)를 사용하였다. 먼저 다엽콜리메이터에 대한 위치의 정확성, 재현성, leaf transmission factor를 측정하였다. 또한 소조사면에 대한 치료계획시스템의 commissioning을 실시하였다. 이를 이용하여 C자 형태의 가상 PTV (Planning Target Volume)에 대해 9개의 빔을 사용하여 세기변조 조사빔을 설계하여, 이를 팬톰 내에서 절대선량 및 상대선량을 측정하여 비교, 분석하였다. 실제 6개의 세기변조 조사빔을 사용하여 치료를 시행한 전립선암 환자를 대상으로, 팬톰내에서 재 계산된 선량계산 결과를 0.015 cc 미소전리함, 다이오드선량계(Scanditronix, 스웨덴), 필름 선량계, 그리고 선형배열다중검출기(array detector) 등을 사용하여 절대선량 및 상대선량을 평가하였다. 결과 : MLC 위치 정확도는 1 mm 이내이었으며, 재현성은 0.5 mm 내외로 평가되었고, leaf transmission 인자는 10MV 광자선에 대해서 interleaf leakage의 경우, $1.9\%$, midleaf leakage의 경우, $0.9\%$로 측정되었다. 필름, 다이오드선량계, 미소전리함, 물팬톰용 전리함(0.125 cc) 등의 반음영을 측정해 본 결과, 물팬톰용 전리함으로 측정된 반음영 영역$(80\~20\%)$은 필름에 비해 2 mm 가량 크며, 최소 beamlet 크기가 5 mm 임을 감안할 때 부적합한 것으로 판명되었다. RTP commissioning 후 계산 선량은 $1\times1\;cm^2$ 크기 소조사면에서의 측정치와 $2\%$ 범위 내에서 일치하였다. C자 형태의 PTV에 대한 9개의 세기변조된 조사빔에 대한 2회에 걸친 치료중심점에서의 절대선량 측정결과 개별 조사빔에 대하여는 $10\%$ 이상 차이를 보였으나 총 선량은 $2\%$ 이내에서 일치하였다. 필름을 이용한 선량분포도도 계산치와 비교적 잘 일치하였다. 실제 치료환자의 팬톰 내에서의 절대선량 측정 결과 총 선량은 $1.5\%$ 차이를 보였다. 각 조사빔에 대해 중심 leaf의 측방선량분포도를 필름 및 선형배열다중검출기를 사용하여 측정하였으며, 조사면 밖에서 계산선량이 $2\%$ 내외로 작게 나타났으나, 특정 위치를 제외하고는 $3\%$ 이내로 잘 일치함을 확인하였다. 결론 : 세기조절방사선치료를 위해서는 다엽콜리메이터의 위치에 대한 보다 정밀한 정도관리 절차가 개발되어야 될 것으로 판단되며, 조사빔내 세기패턴을 효율적으로 확인할 수 있는 정도보증 절차가 필요할 것으로 사료된다. 본원에서는 팬톰 내에서의 치료중심점과 같이 특정 지점에서의 절대선량 확인 및 필름 혹은 선형배열다중검출기를 사용한 세기분포 패턴의 확인 과정을 통하여, 이를 적절히 병행하여 사용함으로써 세기조절방사선치료에 적합한 정도관리를 시행할 수 있었다.

• 중소기업연구
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• 제31권4호
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• pp.67-93
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• 2009

본 연구는 1999년 1월 1일부터 2007년 12월 31일까지 한국거래소의 유가증권시장과 코스닥시장에 상장된 혁신형 중소기업을 대상으로 재무적 제약과 배당스무딩간의 관계를 실증분석 하였으며, 주요한 분석결과는 다음과 같다. 기업들은 목표 배당성향을 가지고 있으며, 실제 배당성향이 목표 배당성향에서 이탈하면 다시 배당지급을 부분적으로 조정한다. 배당조정속도는 Lintner(1956)의 배당조정모형의 핵심변수인 전기 주당배당과 당기 주당이익을 사용하여 거의 대부분 측정할 수 있으며, 잔여배당이론과 그 이후에 등장한 배당신호이론, 대리인이론, 케이터링 이론 및 거래비용이론에 관한 대용변수들은 배당조정속도에 부분적으로 영향을 미친다. 그리고 전기 주당배당은 당기 주당이익보다 배당조정속도에 더 큰 영향을 미치는데, 이는 기업들이 특별한 이유가 없는 한 전기 주당배당 수준을 장기적으로 유지하는 안정적인 배당정책을 선호한다는 증거가 된다. 혁신형 중소기업은 비혁신형 중소기업보다 배당조정속도가 더 빠르다. 혁신형 중소기업은 R&D 투자에 따른 미래의 성장성과 수익성을 담보로 하여 장기적으로 안정적인 배당정책을 유지할 수 있다. 다시 말해, 혁신형 중소기업은 배당지급이 목표 배당성향에서 이탈하더라도, R&D 투자에 따른 미래의 성장성과 수익성을 담보로 하여 목표 배당성향을 향하여 배당지급을 신속하게 조정하여 배당스무딩을 효과적으로 달성할 수 있다. 그리고 혁신형 중소기업 중에서도 재무적 비제약 기업은 재무적 제약 기업보다 배당조정속도가 더 빠르다. 이는 재무적 비제약 기업일수록 자본시장을 통한 외부 자금조달이 용이하기 때문에 주당배당을 신속하게 조정한다는 증거가 된다. 따라서 자본시장 접근성이 용이하여 재무적 제약을 적게 받는 기업일수록 외부 자금조달이 용이하기 때문에 배당지급을 더 신속하게 조정함으로써 배당스무딩을 더 효과적으로 달성할 수 있다. 그리고 중소기업청이 정책적 목적으로 분류한 혁신형 중소기업(벤처기업, 이노비즈기업, 경영혁신형기업)은 비혁신형 중소기업보다 배당조정속도가 더 빠르다. 중소기업청에서 정책적 목적으로 분류한 혁신형 중소기업은 신용보증지원, 정책자금지원, 조세혜택, 공공입찰 우선권 부여 등과 같은 다양한 정책적 혜택으로 인해 재무적 제약을 적게 받기 때문에 배당지급을 더 신속하게 조정할 수 있다. 결론적으로, 한국거래소의 유가증권시장과 코스닥시장에 상장된 혁신형 중소기업은 비혁신형 중소기업보다 배당조정속도가 더 빠르고, 혁신형 중소기업 중에서도 재무적 비제약 기업은 재무적 제약 기업보다 배당조정 속도가 더 빠르다. 다시 말해, 중소기업 중에서도 R&D 집중도가 높은 혁신형 중소기업은 R&D 투자에 따른 미래의 성장성과 수익성을 담보로 하여 배당스무딩을 신속하게 할 수 있고, 혁신형 중소기업 중에서도 자본시장 접근성이 좋은 기업은 재무적 제약을 적게 받기 때문에 배당스무딩을 더 신속하게 할 수 있다. 따라서 중소기업 경영자는 R&D 집중도를 증가시키고 자본시장 접근성을 높여 재무적 제약을 회피함으로써 신속한 배당스무딩을 통해 장기적으로 안정적인 배당정책을 유지할 수 있다고 생각한다. 그리고 중소기업청이 정책적 목적으로 분류한 혁신형 중소기업(벤처기업, 이노비즈기업, 경영혁신형기업)의 경우에도 배당조정속도가 비혁신형 중소기업보다 더 빠르게 나왔다. 이러한 결과는 배당정책의 측면에서 중소기업청의 혁신형 중소기업 정책을 지지하는 실증적인 증거가 된다.

• 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.

• 한국산림과학회지
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• 제22권1호
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• pp.19-48
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• 1974

토지국유원칙(土地國有原則)을 표방(標榜)하고 "공사(公私) 공리(共利)"를 기본원칙(基本原則)으로 하고 있었던 고려조(高麗朝)의 시전과제도(柴田科制度)도 집권력(執權力)의 약화(弱化)로 인(因)하여 조만간(早晩間), 붕괴(崩壞)되고 말았던 것이나 임지제도(林地制度)에 있어서는 분묘설정(墳墓設定)의 자유(自由)와 개간장려(開墾奬勵)를 이용(利用)한 삼림(森林)의 광점(廣占) 및 전시과제도(田柴科制度)로 인(因)한 시지(柴地)의 수조권위양(收租權委讓)으로 유래(由來)된 사적수조권(私的洙組權)이 결부(結付)된 삼림(森林)의 사점현상등(私占現象等)이 점차(漸次) 발전(發展)하여 고려중기(高麗中期)의 국정해지기이후(國政解地期以後)에는 대부분(大部分)의 삼림(森林)이 권력층(權力層)의 사점지(私占地)로 화(化)하여 왔었다. 고려조(高麗朝)의 모든 제도(制度)를 그대로 계승(繼承)한 이조(李朝)는 건국후(建國後) 국가소용(國家所用)의 삼림확보(森林確保)를 위(爲)한 삼림수용(森林收用)의 제도확립(制度確立)이 긴요(緊要)하였음으로 전국(全國)의 삼림(森林)을 국가권력(國家權力)에 의(依)하여 공수(公收)하고 국가(國家)와 궁실소용이외(宮室所用以外)의 모든 삼림(森林)은 사점(私占)을 금(禁)한다는 "시장사점금지(柴場私占禁止)"의 제도(制度)를 법제화(法制化)하였고 도성주변(都城周邊)의 사산(四山)을 금산(禁山)으로 함과 아울러 우량(優良)한 임상(林相)의 천연림(天然林)을 택(擇)하여 전조선용재(戰漕船用材)와 궁실용재(宮室用材)의 확보(確保)를 위(爲)한 외방금산(外方禁山)으로 정(定)하고 그 금양(禁養)을 위(爲)하여 산직(山直)을 배치(配置)하였다. 그리고 연병(練兵)과 국왕(國王)의 수렵(狩獵)을 위(爲)한 강무장(講武場)과 관용시장(官用柴場), 능원부속림(陵園附屬林)의 금벌(禁伐), 금화(禁火)를 제정(制定) 등(等) 필요(必要)에 따라 수시(隨時)로 삼림(森林)을 수용(收用)하였으나 고려조이래(高麗朝以來)로 권력층(權力層)에 의(依)하여 사점(私占)되어온 삼림(森林)을 왕권(王權)으로 모두 공수(公收)하지는 못하였던 것이다. 이조초기(李朝初期)에 있어서의 집권층(執權層)은 그 대부분(大部分)이 고려조(高麗朝)에서의 권력층(權力層)이었던것 임으로 그들은 이미 전조시대(前朝時代)로부터 많은 사점림(私占林)을 보유(保有)하고 있었던 것이고 따라서 그들이 권력(權力)을 장악(掌握)하고 있는 한(限) 사점림(私占林)을 공수(公收)한다는 것은 어려운 일이었으며 그들은 오히려 권력(權力)을 이용(利用)하여 사점림(私占林)을 확대(擴大)하고 있었던 것이다. 또 왕자(王子)들도 묘지(墓地)를 빙자(憑藉)하여 주(主)로 도성주변(都城周邊)의 삼림(森林)을 광점(廣占)하고 있던 터에 성종(成宗)의 대(代) 이후(以後)로는 왕자신(王自身)이 금령(禁令)을 어기면서 왕자(王子)에게 삼림(森林)을 사급(賜給)하였음으로 16세기말(世紀末)에는 원도지방(遠道地方)에 까지 왕자(王子)들의 삼림사점(森林私占)이 확대(擴大)되었고 이에 편승(便乘)한 권신(權臣)들의 삼림사점(森林私占)도 전국(全國)으로 파급(波及)하였다. 임진왜란후(壬辰倭亂後)에 시작(始作)된 왕자(王子)에 대(對)한 시장절급(柴場折給)은 삼림(森林)의 상속(相續)과 매매(賣買)를 합법화(合法化)시켰고 이로 인(因)하여 봉건제하(封建制下)에서의 사유림(私有林)을 발생(發生)시키게 된 것이다. 그리하여 권신(權臣)들도 합법적(合法的)으로 삼림(森林)을 사점(私占)하게 되었고 따라서 이조시대(李朝時代) 임지제도(林地制度)의 기본(基本)이었던 시장사점금지(柴場私占禁止)의 제도(制度)는 건국초(建國初)로부터 실행(實行)된 일이 없었으며 오로지 국가(國家)의 삼림수용(森林收用)을 합법화(合法化)시키는 의제(擬制)에 불과(不過)하였던 것이다. 금산(禁山)은 그 이용(利用)과 관리제도(管理制度)의 불비(不備)로 인(因)하여 산하주민(山下住民)들의 염오(厭惡)의 대상(對象)이 되었음으로 주민(住民)들의 고의적(故意的)인 금산(禁山)의 파괴(破壞)는 처음부터 심(甚)하였고 이로 인(因)하여 국가(國家)에서는 용재림확보(用材林確保)를 위(爲)한 금산(禁山)의 증설(增設)을 거듭하였으나 관리제도(管理制度)의 개선(改善)이 수반(隨伴)되지 않았음으로 금산(禁山)의 황폐(荒廢)는 더욱 증대(增大)되었다. 영조(英祖)는 정국(政局)을 안정(安定)시키기 위(爲)하여 경국대전이후(經國大典以後) 남발(濫發)된 교령(敎令)과 법령(法令)을 정비(整備)하여 속대전(續大典)을 편찬(編纂)하고 삼림법령(森林法令)을 정비(整備)하여 도성주변(都城周邊)의 금산(禁山)과 각도(各道) 금산(禁山)의 명칭대신(名稱代身) 서기(西紀) 1699년(年) 이후(以後) 개칭(改稱)하여온 봉산(封山)의 금양(禁養)을 강화(强化)시키는 한편 사양산(私養山)의 권한(權限)을 인정(認定)하는 등(等) 적극적(積極的)인 육림정책(育林政策)을 퍼려하였으나 계속적(繼續的)인 권력층(權力層)의 삼림사점광대(森林私占廣大)는 농민(農民)들로부터 삼림(森林)을 탈취(奪取)하였고 농민(農民)들 이 삼림(森林)을 상실(喪失)함으로써 국가(國家)의 육림장려등(育林奬勵策)은 효과(効果)를 나타내지 못하였던 것이다. 임진왜란후(壬辰倭亂後)의 국정해이(國定解弛)로 인(因)한 묘지광점(墓地廣占), 왕자(王子)에 대(對)한 삼림(森林)의 절급(折給) 권세층(權勢層)에 대(對)한 산림사점(森林私占)은 인허(認許)하는 입안문서(立案文書)의 발행등(發行等)으로 법전상(法典上)의 삼임사점금지조항(森林私占禁止條項)은 사문화(死文化)되었고 이조말기(李朝末期)에 있어서는 사양산(私養山)의 강탈(强奪)도 빈발(頻發)하고 있음을 볼수 있다. 이와 같이 이조시대(李朝時代)의 시장사점금지조항(柴場私占禁止條項)은 오로지 농민(農民)에게만 적용(適用)되는 규정(規定)에 불과(不過)하였고 이로 인(因)하여 농민(農民)들의 육림의욕(育林意慾)은 상실(喪失)되었으며 약탈적(掠奪的)인 삼림(森林)의 채취이용(採取利用)은은 금산(禁山), 봉산(封山) 및 사양산(私養山)을 막론(莫論)하고 황폐(荒廢)시키는 결과(結果)를 자아냈으며 권력층(權力層)의 삼림점탈(森林占奪)에 대항(對抗)한 송계(松契)의 활동(活動)으로 일부(一部) 공산(公山)이 농민(農民)의 입회지(入會地)로서 보존(保存)되어왔다. 그럼에도 불구(不拘)하고 일제(日帝)는 이조말기(李朝末期)의 삼림(森林) 거의 무주공산(無主公山)이 었던것처럼, 이미 사문화(死文化)된 삼림사점금지조항(森林私占禁止條項)을 활용(活用)함으로써, 국가림(國有林)으로 수탈(收奪)한후(後) 식민정책(植民政策)에 이용(利用)하였던 것이나, 실제(實際)에 있어서 이조시대(李朝時代)의 삼림(森林)은 금산(禁山), 봉산(封山), 능원부속림등(陸園附屬林等)의 관금지(官禁地)와 오지름(奧地林)을 제외(除外)하고는 대부분(大部分)의 임지(林地)가 권세층(權勢層)의 사유(私有) 내지(乃至)는 사점하(私占下)에 있었던 것이다.