• 제목/요약/키워드: Blood vessel

검색결과 756건 처리시간 0.044초

뉴턴유체와 혈액의 맥동유동시 탄성혈관의 운동이 벽면전단응력분포에 미치는 영향 (Effects of Elastic Blood Vessel Motions on the Wall Shear Stresses for Pulsatile Flow of a Newtonian Fluid and Blood)

  • 노형운;김재수;박길문;서상호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집B
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    • pp.318-323
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    • 2001
  • Characteristics of the pulsatile flow in a 3-dimensional elastic blood vessel are investigated to understand the blood flow phenomena in the human body arteries. In this study, a model for the elastic blood vessel is proposed. The finite volume prediction is used to analyse the pulsatile flow in the elastic blood vessel. Variations of the pressure, velocity and wall shear stress of the pulsatile flow in the elastic blood vessel are obtained. The magnitudes of the velocity waveforms in the elastic blood vessel model are larger than those in the rigid blood vessel model. The wall shear stresses on the elastic vessel vary with the blood vessel motions. Amplitude indices of the wall shear stress for blood in the elastic blood vessel are $4\sim5$ times larger than those of the Newtonian fluid. As the phase angle increased, point of the phase angle is are moved forward and the wall shear stresses are increased for blood and the Newtonian fluid.

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맥상 분류 기준에 대한 방법론적 고찰 - "빈호맥학(瀕湖脈學)"을 중심으로 - (The Methodic Study on a Standard of Classification of Pulse Condition -a Focus of ${\ulcorner}$The Pulse Studies of Bin-Ho(瀕湖脈學)${\lrcorner}$-)

  • 이주호;최환수;김철중
    • 한국한의학연구원논문집
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    • 제10권1호
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    • pp.49-61
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    • 2004
  • The Standardization of terms in The Pulse studies(脈學) is a need for development of learning. This study, for the correction of existing misused terms in The Pulse studies, we study on modernly and objectively the terms in The Pulse studies. By a focus of ${\ulcorner}$The Pulse Studies of Bin-Ho(瀕湖脈學)${\lrcorner}$, we studies on the new classification of pulse condition. The error of a existing technical books on Pulse studies begin that the classification of pulse condition is not establish a Standardization. For the correction of existing misused terms in The Pulse studies, we study on the pulse condition is expressed objectively a blood vessel that it is a subject of pulse condition. The expression of blood vessel contain a depth of blood vessel, a speed of pulsation, a curve of blood vessel, thickness of blood vessel, a diameter of blood vessel in expand and contract of blood vessel, a interval in expand and contract of blood vessel, a distinctness on a boundary of blood vessel, a speed of blood flow in blood vessel, a volume of blood flow in blood vessel, a condition of blood in blood vessel, a propelling power of blood vessel. These is standard of the new classification of pulse condition.

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피부미용과 관련된 한방미용경락의 이론적 배정 연구 (A Study on Theoretical Background Relationship of Blood Vessel Pressure Massage and Skin and Management Method of Blood Vessel Pressure Massage for Skin Care)

  • 최정미;나영순
    • 한국패션뷰티학회지
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    • 제2권1호
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    • pp.5-13
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    • 2004
  • This study was analyzed on relationship of blood vessel pressure massage and skin and management method on blood vessel pressure for skin care with Yin-yang 5 factors theory, Yin-yang 5 factors theory of blood vessel pressure massage with related Korean medicine is essential for descriptions of the physiology of human body and disease. Six elements(wind, heat, fire, dryness, wetness, and cold) and seven emotions(anger, happiness, thought, worry, sadness, surprise, and fear) effected on skin care and the five viscera and the six stomach. Blood vessel pressure massage related with skin consists of the five viscera and the six stomach and is improved blood circulation and is retarded aging of skin by controls of hormone and free nerve system. Blood vessel pressure massage for skin care improved in the intestine system and blood circulation and got healthy. The blood vessel pressure massage treatment of beauty art can aid the function of bio-rhythm of a human body and make our body health by healing the problems of the five viscera organs and the six stomach. It also help circulate of the blood flow and vigor. The study expects the related researches to improve the various treatments through this treatment. The researcher encountered many problems with the lack of concerned materials and former studies but expects this study to be a study to retard aging the skin and prevent the diseases through the study of the blood vessel pressure massage.

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선형 트랜스듀서를 이용한 혈관 변형률 영상법 (Blood Vessel Strain Imaging Using Linear Array Transducer)

  • 안동기;정목근
    • 한국산학기술학회논문지
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    • 제11권3호
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    • pp.880-890
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    • 2010
  • 뇌졸중 등의 혈관 질병을 진단하기 위해서 혈관 내 초음파(Intravascular Ultrasound:IVUS)영상 기법이 사용되고 있다. 최근에는 혈관 내벽에 붙은 혈전을 탄성 영상법을 이용하여 진단하는 방법들이 연구되고 있다. 그러나 혈관 내 초음파는 혈관 내에 트랜스듀서를 삽입하여야 하므로 진단 방법에 위험성이 있다. 본 논문은 선형 트랜스듀서를 이용하여 혈관 외부에서 데이터를 획득하여 혈관 내벽에 붙은 혈전의 변형률 영상을 얻었다. 혈관 벽의 움직임을 정확하게 측정하기 위하여, 혈관 벽과 수직이 되도록 주사선의 방향을 조향하면서 초음파 데이터를 획득하였다. 초음파 데이터는 기저대역의 복소수 신호로 복조한 뒤 자기상관(autocorrelation)을 이용하여 혈관 벽의 움직임을 계산하여 변형률 영상을 얻었다. 제안한 방법을 플라스틱 기반의 혈관 모사 팬텀을 제작하여 검증하였다. 혈관 모사 팬텀은 혈관에 해당하는 직경 6mm의 실린더 공간에 물을 채우고 벽을 따라 2mm 두께의 부드러운 혈전을 혈관 벽의 내부에 배치하였다. RF 데이터는 상용 초음파 진단기에서 7.5MHz 선형 트랜스듀서를 사용하여 -40도부터 40도까지 1도 간격으로 조향시킨 81개의 스캔라인 데이터를 얻었다. 실험 결과 단단한 배경 팬텀에 인접한 혈전 영역이 더 무른 것으로 관찰되었다. 제안한 방법의 탄성 영상법이 비록 주사선이 혈관 벽에 수직으로 입사하는 영역으로 제한되지만 혈관 변형률 영상법의 유용함을 실험으로 입증하였다.

A Numerical Analysis on the Curved Bileaflet Mechanical Heart Valve (MHV): Leaflet Motion and Blood Flow in an Elastic Blood Vessel

  • Bang, Jin-Seok;Choi, Choeng-Ryul;Kim, Chang-Nyung
    • Journal of Mechanical Science and Technology
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    • 제19권9호
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    • pp.1761-1772
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    • 2005
  • In blood flow passing through the mechanical heart valve (MHV) and elastic blood vessel, hemolysis and platelet activation causing thrombus formation can be seen owing to the shear stress in the blood. Also, fracture and deformation of leaflets can be observed depending on the shape and material properties of the leaflets which is opened and closed in a cycle. Hence, comprehensive study is needed on the hemodynamics which is associated with the motion of leaflet and elastic blood vessel in terms of fluid-structure interaction. In this paper, a numerical analysis has been performed for a three-dimensional pulsatile blood flow associated with the elastic blood vessel and curved bileaflet for multiple cycles in light of fluid-structure interaction. From this analysis fluttering phenomenon and rebound of the leaflet have been observed and recirculation and regurgitation have been found in the flow fields of the blood. Also, the pressure distribution and the radial displacement of the elastic blood vessel have been obtained. The motion of the leaflet and flow fields of the blood have shown similar tendency compared with the previous experiments carried out in other studies. The present study can contribute to the design methodology for the curved bileaflet mechanical heart valve. Furthermore, the proposed fluid-structure interaction method will be effectively used in various fields where the interaction between fluid flow and structure are involved.

관상동맥질환 위험정도와 혈관탄성의 관계에서 치료지시이행의 매개효과: 경피적 관상동맥 중재술 환자 대상 (Comparison of Vessel Elasticity according to Risk Factors for Coronary Artery Disease, and the Mediating Effects of Treatment Compliance among Patients with Percutaneous Coronary Intervention)

  • 여가람;성경미
    • 동서간호학연구지
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    • 제22권1호
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    • pp.32-40
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    • 2016
  • Purpose: This study aimed to provide basic data for vascular health of patient who underwent percutaneous coronary intervention (PCI) by verifying the mediating effect of compliance in the relationship between risk level of coronary artery disease (CAD) and blood vessel elasticity. Methods: This is a descriptive study with 115 patients, who underwent the PCI a year ago and visited in the cardiology department from January to March, 2015. The risk level of CAD, blood vessel elasticity and the compliance were measured. For data analysis, SPSS/WIN 21.0 and AMOS (IBM) 21.0 were used. Results: There were a positive correlation with blood vessel elasticity score (i.e. inelasticity of the blood vessel wall) (r=.189) and a negative correlation with compliance (r=-.658) in mediating effect of risk level of CAD. There was a negative correlation between compliance and blood vessel elasticity (r=-.482). The direct effect (${\beta}=-.226$), indirect effect (${\beta}=.415$) and total effect (${\beta}=.186$) of mediating effect of risk level of CAD on blood vessel elasticity were significant. Compliance had a partial mediating effect of risk level of CAD on blood vessel elasticity. Conclusion: The results of this study suggest that managing and preventing moderating effect of risk level of CAD on compliance is helpful in restoring blood vessel elasticity.

맥진기를 이용한 좌우 맥파 및 혈관 특성 연구 (A Research of characteristics of left/right pulse wave and blood vessel using Korean medicine pulse diagnosis)

  • 강진호;이한별;김기왕;권정남;이병렬
    • 대한한의학회지
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    • 제35권3호
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    • pp.155-165
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    • 2014
  • Objectives: The pulse diagnosis to identify the symptoms has been considered important in Korean medicine. The position and character of disease would be confirmed by pulse diagnosis of left and right radial artery. This paper is to analyze the characteristics and differences of left and right blood vessels. Methods: In this study, left and right radial artery and dorsalis pedis artery was measured and analyzed by using condenser typed pulse analyzer. Commercially available pulse analyzer was used to measure the radial artery. The pulse wave was measured in 20 laboratory healthy men and women. The blood vessel aging degree and index of augmentation of blood vessel was obtained from the measured pulse wave graph and the characteristics and differences of the left and right blood vessel was analyzed. Results: The significant difference of pulse transit time between the right handed and non-right handed was not found. The correlation of radial artery and dorsalis pedis artery had no significant difference. By obtaining the blood vessel aging index (AGI) and augmentation index (AI) of blood vessel at the left and right radial artery, the significant difference between right handed and non-right handed was not found. Conclusions: The result of this study would help to explain the characteristic of blood vessel with respect to the left and right handed. We suggest that research of pulse wave of the left and right blood vessel using pulse analyzer should be needed in further study.

탄성혈관 내 기계식 인공심장판막(MHV)의 거동 및 혈액 유동 특성에 관한 수치해석적 연구 (A Numerical Analysis on the Motion of Mechanical Heart Valve(MHV) and Characteristics of Blood Flow in an Elastic Blood Vessel)

  • 방진석;최청렬;김창병
    • 한국정밀공학회지
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    • 제22권3호
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    • pp.154-161
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    • 2005
  • In this study, the leaflet motion of a mechanical heart valve and the characteristics of two-dimensional transient blood flow in an elastic blood vessel have been numerically investigated by using fluid-structure interaction method. Here, blood has been assumed as a Newtonian, incompressible fluid. Pressure profiles have been used as boundary conditions at the ventricle and the aorta. As a result, closing motion of the leaflet is faster than opening one. While opening angles of leaflet grow up, vortex is detected at the sinus and backward of the leaflets. When the leaflet is fully closed, vortex is detected at the ventricle and at that moment maximum displacement of the elastic blood vessel is observed in the vicinity of the sinus region. Maximum displacement is caused in association with the blood flow that is oriented toward the elastic blood vessel.

유산소 운동이 중년흡연남성의 혈관건강에 미치는 영향 (Effects of Aerobic Exercise on Middle-aged Male Smokers' Blood Vessel Health)

  • 김종인;정해천;원준연;가성순;오복실
    • 디지털융복합연구
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    • 제12권4호
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    • pp.349-356
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    • 2014
  • 본 연구는 최근 높아지고 있는 혈관질환의 주요 요인인 흡연의 폐해를 유산소 운동을 통해 개선되는지의 여부를 규명하고, 나아가 유산소 운동을 통해 흡연자들의 혈관건강(혈압, 맥압, 혈관탄성)에 운동이 미치는 긍정적인 영향에 대하여 알리고자 하는데 목적이 있다. 대상자들은 40~55세의 흡연남성 40명을 대상으로, 20명은 유산소 운동그룹(Aerobic Exercise Group: AEG), 20명은 비 운동 그룹(Non Exercise Group: NEG)로 나누어 실행하였으며, 대상자 40명의 혈압과 맥압, 혈관탄성을 측정 후 AEG군은 12주간 1주일에 3회, 1회 50분 동안 유산소운동 프로그램에 따라 운동하였고, NEG군은 12주 동안 특별한 실험 조치 없이 평소와 같이 생활하도록 한 후, 12주 후 혈압과 맥압, 혈관탄성을 실험 전과 같은 방법으로 측정하였다. 실험결과 두 그룹 간 수축기 혈압의 차이는 유의한 수준을 나타내지 않았고 이완기 혈압은 유의한 수준을 나타내었다. 맥압의 측정 결과 두 그룹 간 유의한 차이가 나타났다. 혈관탄성의 결과 왼손, 오른손, 왼발, 오른발의 모든 측정 부위에서 두 그룹 간 유의한 차이가 나타났다. 따라서 유산소 운동이 흡연 중년남성의 혈관건강에 긍정적인 영향을 미치는 것으로 나타났다.