• Smart Structures and Systems
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• 제29권2호
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• pp.301-309
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• 2022

Protective coatings are most widely used anticorrosive structures for steel structures. The corrosion under the coating damages the host material, but this damage is completely hidden. Therefore, a field-applicable under-coating-corrosion visualization method has been desired for a long time. Laser ultrasonic technology has been studied in various fields as an in situ nondestructive inspection method. In this study, a comparative analysis was carried out between a guided-wave ultrasonic propagation imager (UPI) and pulse-echo UPI, which have the potential to be used in the field of under-coating-corrosion management. Both guided-wave UPI and pulse-echo UPI were able to successfully visualize the corrosion. Regarding the field application, the guided-wave UPI performing Q-switch laser scanning and piezoelectric sensing by magnetic attachment exhibited advantages owing to the larger distance and incident angle in the laser measurement than those of the pulse-echo UPI. Regarding the corrosion visualization methods, the combination of adjacent wave subtraction and variable time window amplitude mapping (VTWAM) provided acceptable results for the guided-wave UPI, while VTWAM was sufficient for the pule-echo UPI. In addition, the capability of multiple sensing in a single channel of the guided-wave UPI could improve the field applicability as well as the relatively smaller size of the system. Thus, we propose a guided-wave UPI as a tool for under-coating-corrosion management.

• 동의생리병리학회지
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• 제35권6호
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• pp.274-279
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• 2021

This study was conducted to find objective diagnostic indicators for the Eight Principle Pattern Identification using a pulse wave analyzer. Typology Complexion Pulse and Symptom data from 500 women over the age of 18 were used. Five experts made a diagnosis of Eight Principle Pattern Identification and divided the subjects into 'Yin-Yang', 'Exterior-Interior', 'Cold-Heat', 'Deficiency-Excess' groups. Their pulse waves were measured in the left and right radial arteries, and it was investigated whether there was a significant difference between groups in the pulse wave parameter values. 'Yin' group showed a significantly lower value in the left radial artery for Ener, Emin, EIX, T4T, T4TT parameters and in the Right for T2, T2T, T5. The Vmag, As and Ad parameters were significantly different between the 'Exterior' and 'Interior' groups. 'Heat' group showed a significantly higher value in the right radial artery for RAI/t parameter. 'Deficiency' group showed a significantly higher value in the right radial artery for W, Angl parameters. Through this study, significant pulse wave parameters were found, and they can be used as objective diagnostic indicators for Eight Principle Pattern Identification.

• 조명전기설비학회논문지
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• 제26권1호
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• pp.82-86
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• 2012

High-capacity high-voltage pulse generator that can be used for environmental clean-up was developed using transformers. High-voltage pulse is consists of the primary wave and the harmonic wave which are increased as a series circuit using transformers to make pulses. Each transformer has a band-pass characteristics. The output voltage of the pulse width 50[%] was decided. The output voltage of high-voltage pulse generator device was measured as 1.4[kV] (Peak-to-Peak).

• 대한의용생체공학회:의공학회지
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• 제37권4호
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• pp.134-139
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• 2016

US Food and Drug Administration (FDA) approved as a innovative cure for cancer, 1996. The effect is death of cancer cells through necrosis, apoptosis. Mainly the Continuous Wave mode (CW) use for PDT Laser. It sting, the question including itch, and etc. Reportedly, the increase of temperature with the perforated edema, ulcer, necrosis. The Thermal relaxation time and Oxygen recovery time is necessary. To give a normal oxygen recovery time of the cell, used Pulse mode. Progress, it was Burst Pulse mode when easing the thermal wake, the simplicity was secured, the PDT effect is good. Excepted in control group CW, Pulse, Burst pulse mode were incubated with various concentrations of 5-aminolevulinic acid hydrochloride (ALA-5). The tumor size reduction CW mode (44%), Pulse mode (48%), Burst pulse mode (53%) at 4 week after PDT with 0.3, 0.3, 0.3 mg/ml of ALA-5. After 4 hours, investigation of 100, 100, $100J/cm^2$ laser irradiation. The pulse mode was superior in expirimental data analysis. And it was the Burst pulse mode edge head of a family effect.

• 대한융합한의학회지
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• 제6권1호
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• pp.5-20
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• 2024

Objectives: This study was aimed to evaluate the hemodynamic feasibility using pulse parameters as a way to establish safe dose guidelines for Chunwangbosim-dan, and to provide a foundation for developing evidence-based guidelines for clinical use. Methods: Forty-one volunteers were recruited to participate in a study examining the changes in pulse wave characteristics following the ingestion of Chunwangbosim-dan, over a period of 2 weeks, and pulse wave measurements were taken before and after the administration. Pulse wave parameters were measured in this study using a 3-dimensional radial pulse tonometry device(DMP-Lifeplus). In addition, questionnaire, blood pressure, temperature, and body composition were also measured as secondary measures. Results: Fifteen minutes after administration of Chunwangbosim-dan, the non-adverse event group(non-AE) exhibited a statistically significant increase in several power and pressure-related parameters, including h1, h3, h4, h5, SA, PA and PW, while the adverse event group(AE) showed a trend of decreasing stroke volume and increasing Systemic Vascular Resistance Index(SVRI) and applied pressure. After 2 weeks of administration, non-adverse event group(non-AE) exhibited significant changes in standard deviation of pulse rate and HRV_LH ratio. Notably, there are significant differences between AE group and non-AE group in h4/h1, w/t, applied pressure, SV and pulse rate. Conclusion: These findings suggest that pulse parameters may be a useful way to establish safe dosing guidelines for Chunwangbosim-dan. Further research is needed to confirm these results and to develop evidence-based guidelines for clinical use.

• Journal of Power Electronics
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• 제8권2호
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• pp.109-120
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• 2008

In this paper, a novel delta/double-fork transformer based 18-pulse full-wave AC-DC converter is designed, modeled, simulated and developed to feed isolated DC varying loads. The proposed AC-DC converter is used for low voltage and large current DC loads in applications such as electrowinning, where isolation is required mainly for stepping down the supply voltage. The proposed converter improves power quality at AC mains and meets IEEE-519 standard requirements at varying loads.

• 한국한의학연구원논문집
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• 제12권2호통권17호
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• pp.93-101
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• 2006

Pulse feeling is one of the most important diagnosis method in Oriental medicine. But it is not easy to make an objective and standardized diagnosis. In this study, we found how to quantify diagnosis. Specially dally the high practicality in clinic, we search some parameters especially well-related to floating and sinking pulse by statistic analysis. By extension, we find the pulse patterns of the floating and sinking pulse. We choose 15 subjects diagnosed as floating pulse and 15 subjects diagnosed as sinking pulse by oriental doctors. And their pulse signals were acquired by Pulse analyzer which has piezoresistive pressure sensor. For the quantification of the floating and sinking pulse, at first, we examined the parameters which were highly correlated with oriental doctor's diagnosis. And then we derived pulse patterns of the floating-sinking pulse from preprocessed signal and its ensemble average. We also looked trend variation (PH-Curve) between contact and pulse pressure. As a result, statistically there is the biggest difference between contact pressure, the maximum pulse pressure, diastolic area (Ad) and floating and sinking data. Through the PH-Curve, which represented the relationship between contact and pulse pressure, we could divide the floating and sinking pulse clearly. As a basic research of pulse diagnosis algorithm, we can contribute to select essential parameters in diagnosis algorithm And using these diagnosis method, we expect to find typical pulse patterns and some useful parameters about other pulses like slow/rapid, large/fine pulse and so on. We hope that this study will contribute pulse objectification.

• 대한한의학회지
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• 제32권1호
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• pp.1-11
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• 2011

Objectives: The aim of this study was to examine the controversial issues about objective structured clinical examination (OSCE) of pulse diagnosis and investigate the objectification of traditional Korean medicine and technical feasibility of pulse simulation through the suggestion of a pulse simulator. Methods: The concept, validity and reliability of OSCE and the current situation of medical simulation was described. The actual level and problems on the simulator development was presented through haptics and tactile technology in order to compose a pulse simulator for OSCE. Results: The pulse wave system of a pulse simulator should materialize through haptic technology and the classification of the differences between tactile sensation and tactile quality is essential for the development of the relevant pulse simulator for OSCE in traditional Korean medicine. Conclusions: The introduction and controversial issues of OSCE and methodology of pulse wave reappearance system are proposed for the objectification of Traditional Korean Medicine and the development of clinical technology.

• 전력전자학회논문지
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• 제11권3호
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• pp.239-246
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• 2006

본 논문에서는 스텝 펄스형의 멀티레벨 인버터에 적용하기 위한 새로운 사인파 변조기법을 제안하고자 한다. 제안된 변조기법은 레벨수의 증가에 무관하게 스위칭 각의 계산이 쉽고, 각각의 스텝에서 이상적인 정현파와 수학적으로 동일한 실효치를 출력하도록 설계되었으며, 높은 출력레벨의 스텝펄스형 멀티레벨 인버터에서 정현파를 근사적으로 추종하는 파형을 생성할 수 있다. 본 논문에서는 셀 전압비를 이용하여 출력 레벨을 확장한 3셀 구조의 13레벨 케스케이드 H-브리지형 멀티레벨 인버터에 대하여 제안된 변조기법을 적용하였으며 시뮬레이션 및 실험을 통하여 확인하였다.

• 대한임상검사과학회지
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• 제47권1호
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• pp.28-34
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• 2015

Pulse wave velocity (PWV) is used to non-invasively estimate the severity of arteriosclerosis by measuring arterial stiffness. Increased arterial stiffness measured by PWV stands for progressive arteriosclerosis and is caused by atherosclerotic risk factors. This study is focused on how brachial-ankle pulse wave velocity (baPWV) is related to the leading risk factors for arteriosclerosis or atherosclerosis. Subjects were 114, 69 males and 45 females who are in 60's and had baPWV test for acute stroke. The results are as follows: the group with increased arterial stiffness showed significant increase in HbA1c, total cholesterol, BSBP (brachial artery systolic blood pressure), BDBP (brachial artery diastolic blood pressure), CSBP (central artery systolic blood pressure), CDBP (central artery diastolic blood pressure), augmentation index (AIx) and diabetes mellitus. Correlation analysis between baPWV and atherosclerotic risk factor showed significant relationship in age, HbA1c, LDL cholesterol, BSBP, BDBP, CSBP, CDBP and augmentation index. baPWV was independently related to age and BSBP in multiple linear regression analysis. The group with increased arterial stiffness was independently related to BDBP in multiple logistic regression analysis. This study might be meaningful in evaluating the relationship between arterial stiffness and atherosclerotic risk factor in a new way, and be helped to make various studies for cardiovascular disease.