• Title/Summary/Keyword: blood velocity

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Influence of Clothing Pressure on Blood Flow and Subjective Sensibility of Commercial Sports Compression Wear (시판 스포츠 컴프레션 웨어의 의복압이 혈류 및 주관적 감성에 미치는 영향)

  • Kim, Nam Yim;Lee, Hyojeong
    • Fashion & Textile Research Journal
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    • v.21 no.4
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    • pp.459-467
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    • 2019
  • Compression wear provides clothing pressure and affects how blood flows. Facilitating a blood flow is one of the most important functions of compression wear. The wearer's sensibility should be considered when designing compression wear. This study instructed participants to put on 5 types of sport compression wear with different pressure levels (CP-1 to CP-5), measured clothing pressure, blood flow level, blood flow rate, and surface temperature, and examined the pressure level that influenced blood flow through a subjective sensibility assessment. An experiment measured the clothing pressure of compression wear available in the market and found that the pressure ranged 0.6-1.1 kPa for the ankle, 0.7-2.3 kPa for the calf, and 0.9-1.9 kPa for the thigh. Meanwhile, blood flow levels and rates significantly increased when participants wore CP-1, which had the highest clothing pressure level, and CP-2 and CP-4 with middle-level pressure. After exercise, CP-2's surface temperature was the highest and revealed that wearing CP-2 facilitated blood flow. CP-2 was evaluated as most positive in the sensibility assessment and showed a clothing pressure of 0.67-1.82 kPa; its pressure for the calf did not surpass 2.0 kPa. Considering positive physical effect of compression wear on blood flow and subjective psychological effect on participants, CP-2 (0.67-1.82 kPa) would have the most suitable clothing pressure level among other types of the wear in this study.

A Study on the Shear Stress Distribution of the Steady and Physiological Blood Flows (정상 및 박동성 혈류의 전단응력분포에 관한 연구)

  • Suh, S.H.;Yoo, S.S.;Roh, H.W.;Shim, J.W.
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.05
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    • pp.113-116
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    • 1995
  • Steady and physiological flows of a Newtonian fluid and blood in the bifurcated arterial vessel are numerically simulated. Distributions of velocity, pressure and wall shear stress in the bifurcated arterial vessel are calculated to investigate the differences between steady and physiological flows. For the given Reynolds number physiological flow characteristics of a Newtonian fluid and blood in the bifurcated arterial vessel are quite different from those of steady flows. No flow separation or flow reversal in the bifurcated region in the downstream after stenosis appears during the acceleration phase. Also, no recirculation region is seen for steady flows. However, during the deceleration phase the flow began to exhibit flow reversal, which is eventually extended to the entire wall region.

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A Study on the Pulse Doppler System with M-mode Image and Spectrum Analyzer (주파수 해석기와 M-mode 영상을 갖는 펄스 도플러 장치의 개발에 관한 연구)

  • Jeong, Taek-Seob;Park, Sei-Hyun;Kim, Young-Kil
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.1217-1220
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    • 1987
  • We have developed a Ultra Sound Pulsed Doppler System with two-dimensional M-mode image and Spectrum analyzer. The image of the M-mode is composed of time and depth axes. The Spectrum analyzer shows the spectrum of Doppler signal which represents the velocity component of time dependent blood-flow behavior. The spectrogram using Spectrum analyzer is composed of frequency and amplitude axes. The outputs of the system are audio signals, velocity curves, velocity profiles, M-mode images and spectrogram.

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Echo-PIV: in vivo Flow Measurement Technique (에코 PIV: in vivo 유동 측정기법)

  • kim Hyoung-Bum;Hertzberg Jean;Shandas Robin
    • Journal of the Korean Society of Visualization
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    • v.3 no.1
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    • pp.26-35
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    • 2005
  • The combination of ultrasound echo images with digital particle image velocimetry (DPIV) method has resulted in a two-dimensional, two-component velocity field measurement technique appropriate for opaque flow conditions including blood flow in clinical applications. Advanced PIV processing algorithms including an iterative scheme and window of offsetting were used to increase spatial resolution. The optimum concentration of the ultrasound contrast agent used for seeding was explored. Velocity validation tests in fully developed laminar pipe flow and pulsatile flow showed good agreement with both optical PIV measurements and the known analytic solution. These studies indicate that echo PIV is a promising technique for the non-invasive measurement of velocity profiles and shear stress.

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Development of Echo PIV Using Ultrasound Contrast Agent (초음파 조영제를 애용한 Echo PIV 기법의 개발)

  • Kim, Hyoung-Bum
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.12
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    • pp.1528-1534
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    • 2004
  • The combination of ultrasound echo images with digital particle image velocimetry (DPIV) methods has resulted in a two-dimensional, two-component velocity field measurement technique appropriate for opaque flow conditions including blood flow in clinical applications. Advanced PIV processing algorithms including an iterative scheme and window offsetting were used to increase spatial resolution. The optimum concentration of the ultrasound contrast agent used for seeding was explored. Velocity validation tests in fully developed laminar pipe flow result of echo PIV showed good agreement with both optical PIV measurements and the known analytic solution based on a volume flow measurement.

The effects of ultrasound and myofascial release therapy on blood velocity of cranial artery in tension-type headache subjects (초음파와 근막이완술이 긴장형 두통환자의 뇌혈류 속도에 미치는 영향)

  • Han Jong-Man;Kim Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.15 no.1
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    • pp.196-209
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    • 2003
  • The aim of study was compared with the possible role of cranial artery in headache pathogenesis each 2 group (group I : ultrasound therapy alone, group II : myofascial release therapy alone)- divided each 5 tension- type headache patients. Each group were applied ultrasound therapy for 5 minuets and myofascial release therapy for 15 minuets in occipital portion. The study carried out to determine the effects of ultrasound and myofascial release on the cranial arteries velocity from November 11, 2001 to March 29, 2002 the objects were 10 patients who having the tension-type headache at H-hospital. Transcranial doppler ultrasonograpy(TCD) is new non-invasive applicable method to evaluate flow velocities of intrans cranial and extracranial cerebral arteries. TCD was peformed with standard method to measure the Mean Flow Velocity(MFV) of the middle and posterior cerebral arteries, the vertebral arteries.

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Effects of Acupuncture therapy on Cerebral Blood flow in Migraineurs (편두통 환자의 뇌혈류에 대한 침치료의 효과)

  • Kim Dong-Won;Ahn Kyo-Pil;Eom Hoy-Jin;Nam Young;Lee Si-Sup
    • Journal of Acupuncture Research
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    • v.18 no.6
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    • pp.135-140
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    • 2001
  • Objective : To investigate the effects of Acupuncture therapy on the migraineur by way of the change of the Cerebral blood flow. Methods : 6 migraineurs were inserted in acupoints on GV16, G20, S8 during 2 weeks. and, Mean Velocity (MV) and Pulsatility Index (PI) of MCA, PCA, ACA, BA were measured before and after treatments of 2 weeks, respectively. Results : MV of MCA of the migraineurs was decreased very much by 13.3%, and PI was decreased much by 10.4%. However, MV and PI of BA changed little. Conclusion : It is observed that Acupuncture therapy reduces pains of migraineur through decreasing Cerebral blood flow like MCA.

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The Assessment of the Breath Hold and the Free Breath Methods about the Blood Flow Evaluation by Using Phase Contrast MRI (위상대조도 자기공명영상을 이용한 심장 혈류평가에 있어서 호흡정지 기법과 비 호흡정지 기법의 비교평가)

  • Kim, Seong-Ho
    • Journal of radiological science and technology
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    • v.39 no.2
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    • pp.149-156
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    • 2016
  • Measurement of cardiac blood flow using the magnetic resonance imaging has been limited due to breathing and involuntary movements of the heart. The present study attempted to improve the accuracy of cardiac blood flow testing through phase contrast magnetic resonance imaging by presenting the adequate breathing method and imaging variables by comparing the measurement values of cardiac blood flow. Each was evaluated by comparing the breath hold retrospective 1NEX and non breath hold retrospective 1-3NEX in the ascending aorta and descending aorta. As a result, the average blood flow amount/velocity of the breath hold retrosepctive 1NEX method in the ascending aorta were $96.17{\pm}19.12ml/sec$, $17.04{\pm}4.12cm/sec$ respectively, which demonstrates a statistically significant difference(p<0.05) with the non-breath hold retrospective method 1NEX of $72.31{\pm}13.27ml$ and $12.32{\pm}3.85$. On the other hand, the average 2NEX blood flow and mean flow velocity is $101.90{\pm}24.09$, $16.84{\pm}4.32$, 3NEX $103.06{\pm}25.49$, $16.88{\pm}4.19$ did not show statistically significant differences(p>0.05).The average blood flow amount/ velocity of the breath hold retrospective 1NEX method in the descending aorta were $76.68{\pm}19.72ml/s$, and $22.23{\pm}4.8$, which did not demonstrate a significant difference in comparison to non-breath hold retrospective method 1-3 NEX. Therefore, the non breath hold retrospective method does not significantly differ in terms of cardiac blood flow in comparison with the breath hold retrospective method in accordance with the increase of NEX, so pediatric patients or patients who are not able to breathe well must have the diagnostic value of their cardiac blood flow tests improved.

Diabetes affects Peripheral Nerve and Heart Function

  • Ku, Jeong-Min;Choi, Hwa-Sik;Hyun, Kyung-Yae;Moon, Seong-Min;Kim, Dae-Sik;Choi, Seok-Cheol
    • Biomedical Science Letters
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    • v.17 no.4
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    • pp.313-319
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    • 2011
  • Diabetes mellitus (DM) leads to a variety of complications and thus we have retrospectively studied to investigate problems of nerve conduction velocity (NCV) study and the heart in the patients with type-II DM. Blood glucose and blood pressure levels were higher in DM group than in Non-DM group. We found that several latencies were delayed in motor conduction study of upper (median and ulnar nerve) and lower extremities (peroneal and tibial nerve), whereas amplitudes and NCVs were decreased in DM group compared with Non-DM group. Latencies of sensory conduction study in upper and lower extremities (sural nerve) were delayed, while amplitudes and NCVs were lower in DM group than in Non-DM group. Abnormal percent of the electrocardiogram was higher in DM group than in Non-DM group. This retrospective study suggests that type-II DM can cause a damage effect on the peripheral nerve and the heart function.