• Journal of Biomedical Engineering Research
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• v.21 no.4
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• pp.411-417
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• 2000

This paper describes the analysis of the oscillometric method based on the shape of arterial pressure and proposal of a new algorithm for estimating the blood pressure by computer simulation. In the first step, the arterial pressure model which is able to control the shape of arterial pressure was designed and then we simulated the oscillometric model using both the existing exponential model showing the static arterial pressure-volume relation and the designed arterial pressure model. By analyzing the correlation of characteristic ratio based on the shape of arterial pressure, we could find that the characteristic ratio was not the only standard parameter for estimating systolic and diastolic pressure. We were able to estimate the shape of arterial pressure by computing the correlation of arterial pressure shape with oscillation shape. Finally, we proposed an algorithm which is able to estimate systolic and diastolic pressure according to pressure(Pp) table constructed from the relation of maximum amplitude of oscillation and arterial pressure shape. We tested 60 arterial pressure waveforms having various arterial pressure shape and pulse. As a results, the absolute deviation average values of the estimation of systolic, diastolic and mean pressure were 1.62%, 2.40% and 2.20%, respectively. In conclusions, the proposed algorithm showed the possibility of usefullness in estimating the blood pressure.

• Journal of IKEEE
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• v.28 no.2
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• pp.221-227
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• 2024

This paper presents a smartphone-attachable vascular compliance monitoring module. The proposed sensor module measures photoplethysmogram (PPG) and reconstructs an accelerated PPG waveform. The feature points are extracted from the accelerated PPG waves, and vascular compliance is estimated using these extracted features. The module is powered via the smartphone's USB terminal and transmits the acquired waveforms along with vascular compliance values through Bluetooth. The transmitted waveforms and vascular compliance value are displayed through the smartphone application. This work proposes an assessment method for consistency of PPG instrumentation, and it was implemented in a processor of sensor module. The proposed sensor module can be easily attached to smartphone that does not support PPG instrumentation, providing simple measurment and numerical analysis of vascular compliance. To verify the performance of the implemented sensor module, we acquired vascular compliance and pulse pressure data from 29 subjects. Pulse pressure, which serves as a representative indicator of vascular compliance, was obtained using a commercial blood pressure monitor. The analysis results showed that the Pearson coefficient between vascular compliance and pulse pressure was 0.778, confirming a relatively high correlation between two metrics.

• 순환기질환의공학회:학술대회논문집
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• 2001.11a
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• pp.21-21
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• 2001

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.9-9
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• 1998

다목적 실용위성의 궤도전이 및 위성체 자세제어를 위한 추진시스템의 설계요소에는 구조적 안전성, 우주환경에서의 열제어를 위한 회로 및 구성하드웨어 설계, 연료계통 맥압강하를 위한 장치설계 및 추력기 배기가스 영향을 고려한 형상설계 등이 있으며, 설계검증을 위해 부분해석이 수행된다. 또한 발사환경과 우주 궤도환경에서의 추진시스템 성능평가를 위한 연제어계 기능시험, 압력인증시험, 청정도시험 및 내부/외부 누설시험이 수행된다. 본 논문에서는 추진시스템 설계 및 조립공정에 대해 기술하였고, 시험분석을 통해 시스템의 설계 및 조립공정상의 신뢰성을 검증 분석하였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.11a
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• pp.36-38
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• 1993

내피세포 (endothelial cells, EC)는 amine, peptide, 단백, arachidonic acid 및 그 대사물 등의 여러 화학물질에 의하여 내피세포 의전성 이완물질 endothelium-derived relaxing factor, EDRF)을 유리할 뿐만 아니라 맥압(脈壓)과 같은 물리적 변동에 의하여서도 EDRF가 유리된다. EDRF는 처음에 Furchgott와 Zawadzki (1980)에 의하여 보고되었고, EDRF의 실질적인 성분이 무엇인가에 대하여는 그동안 많이 검토되어 왔다(Marshall 와 Kontos, Hong 등, 1990).Ignarro 등 (1987)과 Palmer등 (1987)은 EDRF에 의한 생물학적 반응이 NO (nitric oxide)와 유사하거나 같은 물질이라고 보고하였고,Furchgott 등 (1986)과 Ignarro등 (1988)도 EDRF가 NO와 유사하거나 같은 물질일 것이라고 단정하였다.

• 대한예방의학회:학술대회논문집
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• 2000.10a
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• pp.130-130
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• 2000

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.183-187
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• 2016

The aim of this study was to assess the association between microalbumin and pulse pressure (PP) in Korean adults. The study subjects were Korean adults 20 years or older (n=4,948) who participated in the Korea National Health and Nutrition Examination Survey 2012. The urine microalbumin level ($M{\pm}SE$) was significantly higher (p=0.047) in the high PP group (PP>60.0 mmHg) [$33.02{\pm}4.93{\mu}g/mL$ (95% confidence interval (CI), 23.37~42.68)] than the normal PP group ($PP{\leq}60.0mmHg$) [$22.57{\pm}1.63{\mu}g/mL$ (95% CI, 19.36~25.77)], after adjusting for age, gender, smoking, drinking, regular exercising, WM, BMI, TC, TG, HDL-C, FBG, BUN, creatinine, and urine creatinine. In conclusion, pulse pressure was associated with the microalbumin level in Korean adults.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.197-198
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• 2008

본 논문은 Impedance plethysmography를 이용하여 당뇨병 및 동맥경화의 비침습적이고 고통없는 조기 진단을 위한 시스템 구성의 초기 단계로, 하지 동맥의 기계적 특징인 혈량 변화를 비침습적으로 측정하였다. 혈량과 혈압의 변화는 각각 Impedance plethysmograph와 mercury spbygmomanometer를 이용하여 측정되는데 탄성도는 혈량 변화값을 맥압(수축기압)의 변화량으로 나누어 계산한다. 이 논문에서는 하지 동맥의 탄성도를 비침습적으로 측정하기 위한 전초 단계로서 하지 동맥에서의 임피던스 변화만을 측정하였다. 회로는 50kHz Wien bridge 발진 회로, demodulation, 50kHz band past filter, 0.1Hz high pass filter, 20Hz low pass filter와 증폭기로 구성하였고, 생체 신호 획득 및 처리 과정을 거쳐 임피던스 변화량을 관찰하였다.

• 전기의세계
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• v.28 no.12
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• pp.27-32
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• 1979

13명의 환자에 있어서 새로운 비관혈적 방법에 의한 심박출량을 계산하고, 열희석에 의한 방법으로 측정한 심박출량과 비교하였다. 본 논문에서 사용한 비관혈적 펄스 전달 방법은 대동맥 모델에서의 최적 매개변수 방법을 사용하였다. 모델의 최적 매개변수는 맥압의 첫번째 고주파 전달함수에서 측정치와 계산치의 차이를 최소화하는 조건에 의하여 계산하였다. 전달함수의 2개의 펄스는 각각 경동맥동과 대퇴동맥에서 Piezo-resistive Pulse Microphone을 사용하여 측정하였고, 대동맥의 직경은 초음파 방법을 사용하여 측정하였다. 13명의 환자에게서 16가지 측정을 해서 열희석과 비관혈적 방법은 0.89의 상관계수를 보여주었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2735-2742
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• 2013

The purpose of this study is to assess the association of vitamin D and pulse pressure in Korean adults. The data for analysis were obtained from Korea National Health and Nutrition Examination Survey 2010. PP showed a significant positive correlation with Age(p<0.01), TG(p<0.01), TC(p<0.01), FBS (p<0.01), BMI(p<0.01) and Waist measurement(p<0.01). PP showed a significant negative correlation with HDL-C(p<0.01), Height(p<0.01), Weight(p<0.01) and 25(OH)D(p<0.01). When a multiple linear regression analysis was performed, PP was considered as the dependent variable, Age, Height, Weight, Waist measurement, BMI, TC, TG, HDL-C, FBS and 25(OH)D as independent parameters, PP maintained a significant association only with Age(p<0.001), Waist measurement(p<0.001), FBS(p<0.001), 25(OH)D(p<0.001), TC(p<0.001), Weight(p<0.001), HDL-C(p<0.001). In conclusion, Our results suggest that vitamin D decrease may contribute to higher PP. To maintain standard level of vitamin D may be expected that decrease in incidence of coronary arterial disease.