• 제목/요약/키워드: Blood Characteristics

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협착부가 존재하는 혈관의 유동 특성에 관한 수치 해석적 연구 (A Numerical Analysis on the Hemodynamic Characteristics in the blood vessel with Stenosis)

  • 정훈;박찬국
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1987-1992
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    • 2004
  • Hemodynamics behavior of the blood flow is influenced by the presence of the arterial stenosis. If stenosis is present in an artery, normal blood flow is disturbed. In the present study, characteristics of steady and pulsatile flow of non-Newtonian fluid, the effects of stenosised geometry are analyzed by numerical simulation. One interesting point is that non-symmetric solutions were obtained at severity stenosis, although the stenosis and the boundary condition were all axisymmetric.

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내부직경 변화를 고려한 혈관의 유체-구조 상호작용 해석 (Fluid-Structure Interaction Analysis of Blood Vessel Considering Internal Diameter Variation)

  • 레사 옥타비안티;김동현;김수현;보이케 나바반;변준호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.959-963
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    • 2006
  • A three-dimensional elastic blood vessel model with internal diameter variation is considered to investigate internal flow characteristics and effects of structural deformation. Also, computational analyses for both the rigid model and the fully-coupled FSI model have been conducted in order to compare the shear stress, pressure distribution, and flow velocity in detail. A 70% narrowing area of asymmetric blood vessel model was especially investigated to show the versatility of fluid-structure interaction phenomenon. The results reveal that effect of fluid-structure interaction is very important to accurately investigate the flow characteristics of the blood vessel.

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자기혼합형 LDF 프로브와 혈류 시뮬레이터의 구현 (Implementation of a self-mixing type LDF probe and blood flow simulator)

  • 고한우;김종원
    • 센서학회지
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    • 제8권2호
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    • pp.133-138
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    • 1999
  • In this pager, the authors have implemented a blood flow simulator and a LDF(laser Doppler flowmeter) probe using self-mixing effect of the laser diode. The purpose of the blood flow simulator is to simulate microvascular blood flow in tissue. It consists of melinex film (thickness = $123\;{\mu}m$) which has similar optical characteristics to epidermis and porous polyethylene filter (Vyon, porosity 35%, mean pore size $50\;{\mu}m$, thickness=1 mm) which has similar optical characteristics to dermis. The blood flowmeter probe consists of laser diode(5 mW, 780 nm wavelength), CD lens(focal length 12 mm). current-to-voltage converter, highpass filter, and premplifier. It doesn't need optical fiber, therefore, implementation of the probe is simpler than conventional probe using optical fiber.

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Examination of the Impact of Blood Groups on Group Participation

  • Asgari, Omid
    • 산경연구논집
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    • 제6권2호
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    • pp.25-30
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    • 2015
  • Purpose - Could blood type provide the key to wellness and affect our personality? The theory that blood type is linked to personality (and other mental and physical qualities) is popular mostly in Japan, although it has carried over to Taiwan and South Korea. Research Design, Data, and Methodology - Questionnaires were distributed to 380 production line company employees. The reliability and validity of the questionnaires were examined through independence testing and the average ratio comparison of the two populations. Additionally, using Pearson's chi-square formula, the relationship between the blood group (independent variable) and general group participation (dependent variable) was tested along with the Schuprow coefficient. Result - The prioritization of blood groups over the general group participation was identified and the following results were obtained: Individual group participation is affected by personality features derived from temperament, mood, and other characteristics. Conclusion - The study showed that individual blood groups have an effect on their group cooperation, and among blood groups, blood group A had the greatest tendency to group participation, followed by blood groups O, AB, B, respectively.

대학생 체질량지수와 혈액검사결과 상 비만 분류군간 특성 및 비만 연관 요인 분석에 대한 연구 (The Characteristics in Obesity Classification Group of College Student by Analyzing Their BMI and Blood Test and the Association between Factors Contributing to Obesity and Obesity according to BMI)

  • 박정식;이중재;오현숙;임형호
    • 한방재활의학과학회지
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    • 제24권4호
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    • pp.61-70
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    • 2014
  • Objectives The purpose of this study was to investigate the characteristics in obesity classification group of college students having health checkup by analyzing their BMI and blood test and determine the association between factors contributing to obesity and obesity according to BMI. Methods A group of 2992 test subjects took their medical examination and their body composition, height, weight, blood pressure were measured and blood test was done. With these results we diagnosed obesity, and analysed relationship between obesity and cholesterol, triglyceride, LDL (low density lipoprotein)-cholesterol, HDL (high density lipoprotein)-cholesterol, liver function, renal function and blood pressure. Results 1. Overweight individuals showed high total cholesterol, LDL-cholesterol, triglyceride, GOT (glutamic oxalacetic transaminase), GPT (glutamic pyruvate transaminase), Urea-nitrogen, Creatinine and low HDL-cholesterol. 2. BMI showed a significant association with other factors. BMI has a negative correlation with sex and HDL-cholesterol. BMI had positive correlations with other factors. 3. There was no relation between BMI and sex. Those six factors, liver function, cholesterol, blood pressure, kidney function, neutral fat, and blood sugar were related to BMI. Conclusions There was a significant relation between college students' BMI and their liver function, cholesterol, blood pressure, kidney function, neutral fat, and blood sugar. The diseases related to liver function, cholesterol, blood pressure, kidney function, neutral fat, and blood sugar were clearly associated with obesity.

좌관상동맥 분지부내의 정상혈류와 박동성혈류의 유동특성비교 (Comparison of Steady and Physiological Blood Flow Characteristics in the Left Coronary Artery Bifurcation)

  • 서상호;유상신;권혁문;노형운
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1995년도 추계학술대회
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    • pp.57-60
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    • 1995
  • The objective of this investigation is to understand the role of hemodynamics in the formation and development of atherosclerosis lesions in the human left coronary artery This study also aims to compare the blood flow characteristics of steady and physiological flows. Three dimensional, steady and physiological flows of blood in the left coronary artery are simulated using the Finite Volume Method. Apparent viscosity of blood is represented as a function of shear rate by the Carreau model. Distributions of velocity, pressure and shear stress in tile left coronary artery bifurcation are presented to compare tile steady and physiological flow characteristics.

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혈관내 맥동유동의 FSI 모사 (FSI simulation of pulsatile flow in the blood vessel)

  • 김윤기;김경천
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1484-1486
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    • 2008
  • Characteristics of pulsatile flow in 3-dimensional elastic vessel wall should be investigated in order to understand the physiological blood flow in human body. In this study, the modelling of the physiological blood flow in the elastic blood vessel is proposed. Variation of the pressure and the velocity wavefroms are obtained using the FSI method

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혈액 첨가 수준에 따른 혈액소시지의 품질 특성 (Quality Characteristics on Adding Blood Levels to Blood Sausage)

  • 최윤상;성정민;전기홍;최현욱;서동호;김천제;김현욱;황고은;김영붕
    • 한국식품조리과학회지
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    • 제31권6호
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    • pp.741-748
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    • 2015
  • 본 연구는 영양학적으로 우수한 혈액을 활용한 식육제품의 품질 특성에 미치는 영향을 규명하여 혈액 소시지를 개발하고자 실시하였다. 수분함량, 명도, 적색도, 황색도, 지질 산패도, 응집성, 검성 및 씹음성은 혈액 첨가량이 증가함에 따라 감소하는 경향을 보였으나, 단백질 함량, 지방 함량, 회분 함량, 휘발성 염기태질소 함량은 혈액 첨가량에 따라서 유의적인 차이를 보이지 않았다. 경도 및 탄력성은 혈액을 20% 첨가한 처리구가 다른 처리구들에 비하여 높은 수치를 나타내었다. 또한 혈액을 20% 첨가한 처리구가 전체적인 기호도에서 가장 높은 점수를 받았으며, 색, 풍미, 연도 및 다즙성에서도 혈액을 20%첨가한 처리구가 우수한 평가를 받은 것으로 보여진다. 따라서, 활용도가 낮은 돈육 부산물 중 혈액을 활용하여 혈액 소시지를 제조할 시 혈액의 첨가량이 20%로 하는 것이 혈액 소시지의 품질 및 관능적으로 우수한 혈액 소시지를 제조할 수 있을 것으로 보여진다.

Micro-PIV Measurements of In Vitro Blood Flow in a Micro-Channel

  • Park, Cheol-Woo;Lee, Sang-Joon;Shin, Se-Hyun
    • International Journal of Vascular Biomedical Engineering
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    • 제1권2호
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    • pp.30-35
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    • 2003
  • Flow characteristics of blood flow in a micro channel were investigated experimentally using a micro-PIV (Particle Image Velocimetry) velocity field measurement technique. The main objective of this study was to understand the real blood flow in micron-sized blood vessels. The Reynolds number based on the hydraulic diameter of micro-channel for deionized (DI) water was about Re=0.34. For each experimental condition, 100 instantaneous velocity fields were captured and ensemble-averaged to get the spatial distributions of mean velocity. In addition, the motion of RBC (Red Blood Cell) was visualized with a high-speed CCD camera. The captured flow images of nano-scale fluorescent tracer particles in DI water were clear and gave good velocity tracking-ability. However, there were substantial velocity variations in the central region of real blood flow in a micro-channel due to the presence of red blood cells.

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수술중 및 수술후 혈액보존법 (Intraoperative and Postoperative Blood Conservation in Cardiac Surgery)

  • 이재원
    • Journal of Chest Surgery
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    • 제27권6호
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    • pp.451-454
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    • 1994
  • In February 1991 I initiated a blood conservation program that included hemodilution, use of a cell conservation device to concentrate diluted blood from operative field and from mediastinal shed blood, acceptance of a minimal hematocrit level of 25% in stable patients, and strict avoidance of use of blood products without definitive indication. A retrospective study to evaluate the effects of blood conservation program was designed to compare the amount of homologous transfusion, hematologic data, and postoperative outcome in patients operated on before and after initiation of blood conservation program. Patient characteristics were not different between two groups, before[n = 18] and after[n = 42] initiation of the program. The significant decrease of homologous transfusion[5.2 vs 1.4 units] and the marked increase of nontransfused patients[none vs 57%] in experimental group were due to marked decrease in homologous transfusion during the operation[4.6 vs 0.7 unit]. I conclude that with strict intraoperative blood conservation program, cardiac patients can be operated on with minimal homologous transfusion.

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