• Title/Summary/Keyword: Pulse wave analysis

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Reproducibility of Regional Pulse Wave Velocity in Healthy Subjects

  • Im Jae-Joong;Lee, Nak-Bum;Rhee Moo-Yong;Na Sang-Hun;Kim, Young-Kwon;Lee, Myoung-Mook;Cockcroft John R.
    • International Journal of Vascular Biomedical Engineering
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    • v.4 no.2
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    • pp.19-24
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    • 2006
  • Background: Pulse wave velocity (PWV), which is inversely related to the distensibility of an arterial wall, offers a simple and potentially useful approach for an evaluation of cardiovascular diseases. In spite of the clinical importance and widespread use of PWV, there exist no standard either for pulse sensors or for system requirements for accurate pulse wave measurement. Objective of this study was to assess the reproducibility of PWV values using a newly developed PWV measurement system in healthy subjects prior to a large-scale clinical study. Methods: System used for the study was the PP-1000 (Hanbyul Meditech Co., Korea), which provides regional PWV values based on the measurements of electrocardiography (ECG), phonocardiography (PCG), and pulse waves from four different sites of arteries (carotid, femoral, radial, and dorsalis pedis) simultaneously. Seventeen healthy male subjects with a mean age of 33 years (ranges 22 to 52 years) without any cardiovascular disease were participated for the experiment. Two observers (observer A and B) performed two consecutive measurements from the same subject in a random order. For an evaluation of system reproducibility, two analyses (within-observer and between-observer) were performed, and expressed in terms of mean difference ${\pm}2SD$, as described by Bland and Altman plots. Results: Mean and SD of PWVs for aorta, arm, and leg were $7.07{\pm}1.48m/sec,\;8.43{\pm}1.14m/sec,\;and\;8.09{\pm}0.98m/sec$ measured from observer A and $6.76{\pm}1.00m/sec,\;7.97{\pm}0.80m/sec,\;and\;\7.97{\pm}0.72m/sec$ from observer B, respectively. Between-observer differences ($mean{\pm}2SD$) for aorta, arm, and leg were $0.14{\pm\}0.62m/sec,\;0.18{\pm\}0.84m/sec,\;and\;0.07{\pm}0.86m/sec$, and the correlation coefficients were high especially 0.93 for aortic PWV. Within-observer differences ($mean{\pm}2SD$) for aorta, arm, and leg were $0.01{\pm}0.26m/sec,\;0.02{\pm}0.26m/sec,\;and\;0.08{\pm}0.32m/sec$ from observer A and $0.01{\pm}0.24m/sec,\;0.04{\pm}0.28m/sec,\;and\;0.01{\pm}0.20m/sec$ from observer B, respectively. All the measurements showed significantly high correlation coefficients ranges from 0.94 to 0.99. Conclusion: PWV measurement system used for the study offers comfortable and simple operation and provides accurate analysis results with high reproducibility. Since the reproducibility of the measurement is critical for the diagnosis in clinical use, it is necessary to provide an accurate algorithm for the detection of additional features such as flow wave, reflection wave, and dicrotic notch from a pulse waveform. This study will be extended for the comparison of PWV values from patients with various vascular risks for clinical application. Data acquired from the study could be used for the determination of the appropriate sample size for further studies relating various types of arteriosclerosis-related vascular disease.

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A Study of Mili-wave Pulse Accelerating For High Power Electron Beam (대 전력 전자빔 가속용 밀리파 펄스 연구)

  • Kim, Won-Sop;Kim, Jeong-Man;Kim, Yeong-Min
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1554-1555
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    • 2006
  • We have studied the backward wave oscillator, a power pulsed generator oscillator at 20 GHz has higher frequency then current one. An absolute instability linear analysis was used for the purpose of designing the slow wave structure. A large diameter of the slow wave structure was adopted to prevent the breakdown brought about by the increase of power density.

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An analysis of new driving wave form Using Sine Wave on AC-PDP (Sine파를 이용한 새로운 AC-PDP 구동 파형 해석)

  • Choi, Won-Young;Ok, Jung-Woo;Choi, Joon-Young;Yoo, Su-Bok;Lee, Hae-Jun
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1521-1522
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    • 2006
  • Cathode ray tube(CRT)를 대체 할 수 있는 차세대 display 중 plasma display panels(PDPs)가 각광받고 있지만, 여전히 효율 개선은 중요한 과제이다. 본 연구에서는 기존의 PDP driving 중 발광영역에 sine wave를 접목시켜 수치해석하였다. 수치 해석은 2차원 fluid-code simulator를 사용하였고, 여러가지 sine wave형태와 세폭 pulse를 조합하여, 30%이상의 효율 향상을 얻을 수 있었다.

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Shear Wave Velocity in Unconsolidated Marine Sediments of the Western Continental Margin, the East Sea

  • Kim, Gil-Young;Kim, Dae-Choul
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.4E
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    • pp.167-175
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    • 2003
  • Shear wave velocity was measured and grain size analysis was conducted on two core samples obtained in unconsolidated marine sediments of the western continental margin, the East Sea. A pulse transmission technique based on the Hamilton frame was used to measure shear wave velocity. Duomorph ceramic bender transducer-receiver elements were used to generate and detect shear waves in sediment samples. Time delay was calculated by changing the sample length from the transducer-receiver element. Time delay is 43.18 μs and shear wave velocity (22.49 m/s) is calculated from the slope of regression line. Shear wave velocities of station 1 and 2 range from 8.9 to 19.0 m/s and from 8.8 to 22 mis, respectively. Shear wave velocities with depth in both cores are qualitatively in agreement with the compared model〔1〕, although the absolute value is different. The sediment type of two core samples is mud (mean grain size, 8-9Φ). Shear wave velocity generally increases with sediment depth, which is suggesting normally consolidated sediments. The complicated variation of velocity anisotropy with depth at station 2 is probably responsible for sediment disturbance by possible gas effect.

The Relationship between Pulse Wave Velocity (PWV) and Risk Factors of Cardiovascular Disease including Serum Lipid Values (Pulse Wave Velocity(PWV)와 혈청지질수치를 포함한 심혈관 질환 위험 요인들과의 상관관계 연구)

  • Jeong, Seung-Hwan;Um, Eun-Jin;Park, Woo-Rham;Lee, Beom-Jun;Na, Byung-Jo
    • The Journal of Internal Korean Medicine
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    • v.30 no.3
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    • pp.525-533
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    • 2009
  • Objectives : There are lots of reports that cardiovascular disease, including hypertension, cerebro-vascular accident, and coronary heart disease, is related to atherosclerotic changes. Increased serum levels of lipids could play a role in these changes. This study aimed to investigate the relationship between PWV and risk factors of cardiovascular disease, including serum lipid values. Methods : This study included 261 subjects ($49.32{\pm}11.79$ years, 112 male) who underwent PWV and serum lipid evaluation. We investigated the correlation between serum lipid values, blood pressure, body mass index (EMI) and PWV. Pearson's correlation and partial correlation analysis were applied to examine the relationship between PWV and risk factors of cardiovascular disease. Results : Serum triglyceride, total cholesterol, systolic blood pressure, and diastolic blood pressure were significantly correlated with PWV. Partial correlation coefficient adjusted by age yielded significant correlation between serum triglyceride, systolic blood pressure, diastolic blood pressure and PWV. Conclusion : In this study, it seems that there are significant relationships between PWV, triglyceride and blood pressure. We could suggest that PWV might have some relationships with Dam-eum and blood stasis in oriental theory.

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Measurement of a Blood Velocity by using Photoplethysmograph and Radial Artery Pulse Wave Equipped with Magnetic Hall Device (자성 홀소자 맥진기와 용적맥파계의 맥진파형을 이용한 혈류속도 측정 연구)

  • Jang, Deok-Hyeong;Kim, Dam-Bee;Choi, Suel-Gi;Lee, Sang-Suk
    • Journal of the Korean Magnetics Society
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    • v.22 no.4
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    • pp.130-135
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    • 2012
  • One prototype product of clip-type pulsimeter equipped with magnetic field sensing semiconductor Hall device after one permanent magnet attached "Chwan" position in center of a radial artery was developed. The clip-pulsimeter was composed of the hard ware system measuring to voltage signals. To measure the blood velocity, the radial artery pulsimeter is simultaneously connected the PPG (photoplethysmograph). Analysis and comparison of two pulse waves data has done obtained from a clinical test of forty subjects of 20 ages. The value of a blood velocity simultaneously measured from a radial artery puls wave and PPG is an average value of 0.8m/s. The usage of this research results is possible to store the biomedical signals for health care.

Analysis of multi-channel photoplethysmograph parameter by the changes of arterial characteries (동맥계 다채널 용적맥파 특징 파라미터 분석에 관한 연구)

  • Han, Soon-Chen;Kim, Hyoung-Jo;Kim, Hyoung-Tae;Kim, Jung-Kuk;Huh, Woong
    • Proceedings of the IEEK Conference
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    • 2003.07c
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    • pp.2745-2748
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    • 2003
  • In this paper, we implement the photoplethysmo-graphy system that have three channel pulse wave detects and one channel ECG amplifier. In order to detect the artery state, we measured the pulse waves at different positions, simultaneously. In general, arterial vascular system suffers the decrease of compliance, increase of resistance, and decrease of distensibility through aging. Therefore, we compared and analyzed variation of tile Pulse waves parameter both in time and frequency domains that is concerned with the changes of arterial characteries. And then evaluated the correlation coefficients between the parameters variation and the age group. As the result of experiment, we found that the Parameters have a significant correlation about aging.

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Analysis of Effects of Phase Noise in Radar System (위상잡음이 레이더 시스템에 미치는 영향 분석)

  • Park, Jinsung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.3
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    • pp.373-381
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    • 2013
  • In this paper, the effects of phase noise on the radar system were analyzed in terms of 3 point of view. The impact(s) on the compressed pulse waveform, the FMICW(Frequency Modulated Interrupted Continuous Wave) radar performance and the receiver sensitivity were investigated. From the investigation, it was indicated that the phase noise over 10 kHz offset frequency makes the side lobe level of compressed pulse worse. Also it was founded that the FMICW radar performance, especially at the noise level of range profile, is related to the phase noise. Finally, the investigation showed that the phase noise at local oscillator affects the receiver sensitivity.

MM PWM Scheme for High Performance and Harmonic Effects Minimization of VSI-IM Drive System (VSI-IM 구동시스템의 고동작 및 고주파영향 최소화를 위한 MM PWM 방식)

  • Min Soo Kim
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.1
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    • pp.42-48
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    • 1988
  • MM(multimode) PWM(pulse width modulation) Suitable for high performance and harmonic effects minimization of VSI (voltabge source invertetr)-IM (induction motor)drive system is proposed. The approximated optimal, suboptimal and optimal PWM are implemented in the low frequency range, while square wave operation is realized in the hibh frequency range. The pulse width Modulator is capable of generating control signals to a transistorized inverter operating at about 1KHz. All functions except digital comparison have been implemented in softyware making the scheme economical, flexible and reliable. Pulse width modulator is built and tested experimentally. In order to confirm the effectiveness and the reliability of the theoretical proposition, this scheme is applied to 1Hp, Three phase IM. As results, it is concluded that the scheme of MM PWM is superior to other conventional switching scheme through the discussions or analysis carried out on the items such as line-to-line voltage, current and spectrum of current harmonic components observed at the output terminal of inverter, noise level of motor.

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Analysis of the Pulse Distortion on Tapered Microstrip Lines (테이퍼형 마이크로스트립 선로에서 펄스의 왜곡 특성 분석)

  • Kim, Gi-Rae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.8
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    • pp.45-51
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    • 2000
  • The distortion of an electrical pulse, which has a rise/fall time due to the dispersion and the reflection, on tapered microstrip lines has investigated In time domain. The voltage and current transfer functions are shown for the tapered line. The dispersion distortion obtained by using these trans(or functions are represented for the nonideal square pulse along the triangular, Tchebycheff and exponential tapered lines, and analyzed the influence of the reflection and the frequency dispersion on the distorted voltage wave in the tapered lines. The observed overshoot in front of the distorted wane is caused due to the frequency dispersion and the sustained tail of that comes from the reflection in the tapered line.

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