• Journal of the Korean Magnetics Society
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• v.22 no.1
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• pp.27-31
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• 2012

Two radially arterial pulses of both hands using the prototype of a clamping clip pulsimeter equipped with permanent magnet and Hall device are compared and analyzed. The phase difference of two pulse wave signals is dominantly presented from the simultaneous measuring clinical pulse wave signals for twenty two male participants at their 20's. It is possible to analyze that the fast and slow pulse wave for right hand and left hand depend on the muscle property of arms rather than the total length of blood vessel due to cardiovascular circulatory system.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.204-209
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• 2014

The purpose of this study is to produce a simulator that can control a pulse pressure keeping the pulse wave transfer phenomenon. For this, the elastic tube is combined with a compliance chamber for the vessel part. The simulator is comprised of four parts; a pressure generation part with slider-crank mechanism, a vessel part with resistance controller, water reservoirs and a measurement part. The changes of waveform depending on the location of a chamber is examined to determine the position of a chamber. The effects of a chamber on the pulse pressure and the pulse wave transfer phenomenon were investigated. It showed that the simulator which had the chamber in upstream of tube produces pressure wave, being more similar to the clinical waveform than in downstream of tube. Furthermore, with the chamber, the simulator generates a pulse pressure, being more similar to the normal physiological values than without one. The chamber had little effect on the pulse wave velocity.

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.224-225
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• 2015

Ultrasonic velocity method is applied to measure and correlate the strength of concrete to the velocity of the ultrasonic wave. With voids inside, mortar specimens may show the lower strength and it is intended to detect such change using the ultrasonic velocity method in this study. The amount of voids was varied and the measured data represented the condition of the mortar with voids. The test results can be used to predict the strength of concrete with voids using ultrasonic velocity method.

• Proceedings of the Korean Magnestics Society Conference
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• 2012.11a
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• pp.140-142
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• 2012

• Smart Structures and Systems
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• v.7 no.4
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• pp.241-262
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• 2011

Cast iron pipe has been used as a water distribution technology in North America since the early nineteenth century. The first cast iron pipes were made of grey cast iron which was succeeded by ductile iron as a pipe material in the 1940s. These different iron alloys have significantly different microstructures which give rise to distinct mechanical properties. Insight into the non-destructive structural condition assessment of aging pipes can be advantageous in developing mitigation strategies for pipe failures. This paper examines the relationship between the small-strain and large-strain properties of exhumed cast iron water pipes. Nondestructive and destructive testing programs were performed on eight pipes varying in age from 40 to 130 years. The experimental program included microstructure evaluation and ultrasonic, tensile, and flexural testing. New applications of frequency domain analysis techniques including Fourier and wavelet transforms of ultrasonic pulse velocity measurements are presented. A low correlation between wave propagation and large-strain measurements was observed. However, the wave velocities were consistently different between ductile and grey cast iron pipes (14% to 18% difference); the ductile iron pipes showed the smaller variation in wave velocities. Thus, the variation of elastic properties for ductile iron was not enough to define a linear correlation because all the measurements were practically concentrated in single cluster of points. The cross-sectional areas of the specimens tested varied as a result of minor manufacturing defects and levels of corrosion. These variations affect the large strain testing results; but, surface defects have limited effect on wave velocities and may also contribute to the low correlations observed. Lamb waves are typically not considered in the evaluation of ultrasonic pulse velocity. However, Lamb waves were found to contribute significantly to the frequency content of the ultrasonic signals possibly resulting in the poor correlations observed. Therefore, correlations between wave velocities and large strain properties obtained using specimens manufactured in the laboratory must be used with caution in the condition assessment of aged water pipes especially for grey cast iron pipes.

• 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.

• Journal of Korean Academy of Nursing
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• v.40 no.5
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• pp.705-713
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• 2010

Purpose: To investigate the effectiveness of aromatherapy on blood pressure, heart rate variability, aortic pulse wave velocity and the aortic augmentation index of essential hypertensive patients. Methods: Using a coin toss, 22 participants were assigned to the experimental group and 20 to the control. The experimental group was given a blend of oils of lemon (Citrus limonum), lavender (Lavandula angustifolia), and ylang ylang (Cananga odorata) which were prepared in the ratio of 2:2:1, respectively. The control group was given an artificial lemon fragrance of Limonene (35 cc) and Citral (15 cc) mixture. The experiment, inhalation, was conducted for 3 weeks (2 min per inhalation, 2 times per day) to both groups. Results: There was a noticeable difference in systolic blood pressure between the groups (p=.001), however the difference in diastolic blood pressure between the two groups was not significant. There was a notable difference in sympathetic nerve system activity of heart rate variability (p=.047). However, the differences in aortic pulse wave velocity or the aortic augmentation index were not significant. Conclusion: Aromatherapy is effective in lowering systolic blood pressure and sympathetic nerve system activity.

• Biomedical Science Letters
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• v.15 no.1
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• pp.9-15
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• 2009

Early age at menarche, which is indicator of early biological maturity, has been shown to be associated with increased adult body mass index. Early menarche has also been associated with many cardiovascular disease risk factors and metabolic syndrome. To evaluate the impact of menarche to cardiovascular risk factor, we assessed by age at menarche, brachial-ankle pulse wave velocity (baPWV), which represents arterial stiffness, in women with or without metabolic syndrome. The subjects recruited for this study were three hundred one women. Relatively early menarche and relatively late menarche were classified according to less than $50^{th}$ percentile for relatively early menarche, and great than the $50^{th}$ percentile for relatively late menarche. Subject were divided four group, 1) women who had not adulthood metabolic syndrome and relatively early menarche, 2) women who had not adulthood metabolic syndrome and relatively late menarche, 3) women who had adulthood metabolic syndrome and relatively early menarche, 4) women who had adulthood metabolic syndrome and relatively late menarche. Women who had a relatively early menarche with adulthood metabolic syndrome had significantly high levels of blood pressure, triglyceride, fasting insulin and homeostatic model assessment of insulin resistance (HOMA-IR) levels than women with late menarche with adulthood metabolic syndrome, and had significantly lower HDL-cholesterol levels. And also, women who underwent a relatively early menarche with metabolic syndrome had highest level of baPWV in adult. In this study we found effect of age at menarche on adulthood metabolic risk factors for cardiovascular disease (e.g., baPWV, insulin resistance, hyperlipidemia) in Korean women.

• Journal of the Korean Institute of Navigation
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• v.20 no.3
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• pp.85-95
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• 1996

In the velocimeter, the ultrasonic pulse signal is used for measuring the profile velocity of moving targets distributed in space because of the merits of its high distance resolution and harmless affect to the human body. The velocity reading in conventional ultrasonic pulsed velocimeter depends on the wave pattern reflecting the spatial distribution of scatters and includes observational error due to the signal processing of analyzing pulse signal. In this paper, we evaluate an influence of the received waveform of pulsed signal on the velocity information by setting a model. Subsequently, in order to improve the distance resolution and to obtain precise velocity information without the influence of the spatial distribution of scatterers, we propose a new method for the analysis of Doppler pulsed signal, in which the pulsed signal is transformed into a phase function with local data. Finally, it is confirmed that the performance of the velocimeter is more improved in the proposed method than in the conventional one.