• Journal of Sensor Science and Technology
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• v.20 no.5
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• pp.343-350
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• 2011

The compliance and stiffness of artery are closely related with disease of arteries. Pulse wave velocity(PWV) in the blood vessel is a basic and common parameter in the hemodynamics of blood pressure and blood flow wave traveling in arteries because the PWV is affected directly by the conditions of blood vessels. However, there is no standardized method to measure the PWV and it is difficult to measure. The conventional PWV measurement has being done by manual calculation of the pulse wave transmission time between coronary arterial proximal and distal points on a strip chart on which the pulse wave and ECG signal are recorded. In this study, a pressure sensor consisting of strain gauges is used to measure the blood pressure of arteries in invasive method and regular ECG electrodes are used to record the ECG signal. The R-peak point of ECG is extracted by using a reference level and time windowing technique and the ascending starting point of blood pressure is determined by using differentiation of the blood pressure signal and time windowing technique. The algorithm proposed in this study, which can measure PWV automatically, shows robust and good results in the extraction of feature points and calculation of PWV.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.2
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• pp.131-134
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• 2008

Purpose: The objective of this study was to evaluate the clinical parameters in terms of the midazolam sedation in patients undergoing dental practice. Patients and Methods: Total 28 patients were included in this study. They received the dental practice in the daycare center and sedation was done with midazolam. The recorded variables were blood pressure, pulse rate, $SpO_2$, and patient's response. The differences between observations were analyzed with paired samples t-test. Results: The blood pressure was significantly decreased after the administration of midazolam and the systolic pressure was significantly increased at the start of operation (P<0.05). The pulse rate was significantly increased after lidocaine injection (P<0.001). The amnesic effect was shown 21 cases out of 28 cases (75%). Conclusions: The effect of midazolam on pulse rate was not significant. However, midazolam could decrease the blood pressure significantly. Therefore, the sedation with midazolam could be successfully used in the dental practice, particularly for the patients having the hypertension.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.749-750
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• 2012

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.94-96
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• 2007

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.3
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• pp.485-501
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• 1997

Pressure control is possible driving a simple ON/OFF 3-way valve of hydraulic servo system by pulse width modulation signal. But the pressure varies according to the duty ratio and carrier frequency and repeated on-off action induces pressure fluctuation. So equations for mean pressure and ripple amplitude are theoretically derived as a function of on/off time, the system parameters which decide the pressure characteristics are arranged and they are verified by experimental study. As the result selection criteria for the major design parameters are established and the basic strategy to suppress the unnecessary fluctuation can be provided for a hydraulic pressure control system using these type of valves.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.107-111
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• 1997

Pressure control is possible by pulse width modulation signal driving a simple ON/OFF 2-way valve of hydraulic servo system. But it indices pressure fluctuation due to repeated on-off action and the pressure varies according to the duty ratio and carrier frequency. So mean pressure and ripple amplitude are arranged by experimental study as the driving signal change which decides the pressure characteristics. As the result selection criteria of the major design parameters may be established and the basic strategy to suppress the unnecessary flucturion may be provided for a hydraulic pressure control system.

• Journal of Acupuncture Research
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• v.25 no.4
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• pp.51-58
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• 2008

Objectives : Sypsun-points are located at the tips of all fingers, 0.1 chon(寸) from the finger nails, totaling 10 points on both hands. These points have been used for emergency care, fainting, epilepsy, cerebrovascular accidents, hypertension, unconsciousness, high fever etc. in oriental medicine. The most common technique is bleeding with a needle at these points. We investigated whether Venesection at the Sybsun-points has effects on blood pressure and body temperature and pulse rate in humans aged from 20 to 30 who had no specific past history and whose vital signs are in normal range. Methods : 67 persons were studied from March to June 2008. They were composed of Sample group(n=36) and Normal group(n=31). Both two groups kept a steady state an hour before venesection. In both group, we checked blood pressure and body temperature and pulse rates 6 times( 30min. before and just before treatment, and just after, 30, 60, 90min after treatment). All study environments were same between sample and normal group. But only, normal group didn't carry out venesection at the Sybsun-points. Results : In a comparison of before and after venesection at the Sybsun-points, any Statistical significance was not evaluated. Though pulse rate in sample group was significantly decreased after venesection(p<0.05), it has no statistical significance because normal group's pulse rate was also significantly decreased and between two groups had no statistical difference. Conclusions : Though further study is needed, our findings suggest that venesection at the Sybsun-points has no significant effect on blood pressure and body temperature, and pulse rate in humans who had no specific past history and whose vital signs are in normal range. Also in that case, we may know that pain and tension result from venesection at the Sybsun-points have no significant effect on blood pressure and body temperature and pulse rate.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.606-611
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• 2004

In East-South Asia it has been known that Korean ginseng(Panax ginseng) increases blood pressure, whereas American ginseng(Panax quinquefolius) doesn't. This study was designed to find out if Korean ginseng really could increase blood pressure comparing with American ginseng. Double-blind randomized controlled trials on blood pressure and pulse rate of Korean ginseng and American ginseng in Koreans and Chineses was performed. There was no significant difference on blood pressure and pulse rate between Korean ginseng and American ginseng in both Koreans and Chineses by repeated-measures ANOVA. It was revealed that Korean ginseng does not increase blood pressure. Maybe the concept that Korean ginseng increases blood pressure is concerned with commercial interests dealing with American Ginseng.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.186-191
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• 2009

In the study on the waveform analysis of radial artery pulse diagnosis, we need to establish fundaments of contemporary pulse diagnosis research. As we will to do experimental research on the difference of pulse waveform on the radial artery with applied variations of pressure(5 stage-pressure) and measuring position(CHON, KWAN, CHEOG). First of all, in this research, we did the experiment of the study on the waveform analysis of radial artery(left KWAN) pulse dignosis by using 3 dimension pulse meter and analyzer (3D MAC). As a result. we extracted the seven measurement fluents : energy(E), size of cycle(h1), size of reflection cycle(h2), time of reflection cycle(t2), time of contraction (t4), width of cycle(w), area of waveform(A) by the statistically reasonable differences. We expect that the seven measurement fluents contribute to divide the situation through the results of waveform analysis of radial artery.

• Transactions of Materials Processing
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• v.26 no.5
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• pp.314-322
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• 2017

In the high-speed forming analysis, dynamic material properties considering a high strain rate are required. The split Hopkinson pressure bar (SHPB) experiment was performed for measuring dynamic material properties under high strain rate. The pulse shaping method was used to improve the accuracy of the SHPB experiment. A pulse shaper attached to the front of the incident bar was used for specimen dynamic stress equilibrium through stress wave control. Numerical analysis and SHPB test were performed to verify whether the pulse shaper affects the dynamic stress equilibrium in copper and Al6061 specimens. The results of SHPB test and numerical analysis show that the pulse shaper contributes to the dynamic stress equilibrium. Based on the improved stress equilibrium using a pulse shaper, the flow stress curves for copper and Al6061 materials were obtained at strain rates of 1344.4/sec and 1291.6/sec, respectively.