• Journal of Computing Science and Engineering
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• v.5 no.3
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• pp.246-256
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• 2011

Due to the increasingly aging population, there is a rising demand for assistive living technologies for the elderly to ensure their health and well-being. The elderly are mostly chronic patients who require frequent check-ups of multiple vital signs, some of which (e.g., blood pressure and blood glucose) vary greatly according to the daily activities that the elderly are involved in. Therefore, the development of novel wearable intelligent systems to effectively monitor the vital signs continuously over a 24 hour period is in some cases crucial for understanding the progression of chronic symptoms in the elderly. In this paper, recent development of Wearable Intelligent Systems for e-Health (WISEs) is reviewed, including breakthrough technologies and technical challenges that remain to be solved. A novel application of wearable technologies for transient cardiovascular monitoring during water drinking is also reported. In particular, our latest results found that heart rate increased by 9 bpm (P < 0.001) and pulse transit time was reduced by 5 ms (P < 0.001), indicating a possible rise in blood pressure, during swallowing. In addition to monitoring physiological conditions during daily activities, it is anticipated that WISEs will have a number of other potentially viable applications, including the real-time risk prediction of sudden cardiovascular events and deaths.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1339-1342
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• 2007

In this study, we determined the optimum electrode pair for measuring the abdominal pressure using bio-impedance method and compared with conventional methods. Because impedance changes differ from a weight, a height, contractile force, volume of muscle and blood other or whatever of individuals, it was quantified using values of impedance change, correlation coefficient and SNR. Our results showed the optimum electrode pair (1, 9) which could detect impedance changes due to an increase of the intensity of the abdominal pressure. The correlation coefficient and quadratic function between the RMS values of EMG and the impedance changes were 0.87 and $y=0.0014x^2+0.0620x+0.6958$, respectively. It demonstrated that the abdominal pressure could be measured noninvasively and simply using bio-impedance method. We propose that this optimum electrode configuration would be useful for future studies involving the convenient measurement of abdominal pressure by ambulatory urodynamics monitoring study.

• Journal of Biomedical Engineering Research
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• v.27 no.6
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• pp.370-375
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• 2006

The purpose of this work is to predict the systolic blood pressure (BP) during exercise from pulse transit time (PTT) for warning of possible danger. PTT was calculated as the time between R-peak of ECG and the peak of differential photoplethysmograph (PPG). For the PTT-BP model, we used regress equations from previous studies and 3 kinds of new models combining linear and nonlinear regress equation. The model parameters were estimated with the data measured under low to middle intensity exercise, and then was tested with the data measured under high intensity exercise. Predicted BP values after high intensity exercise were compared with those measured by cuff-type sphygmomanometer. The results showed that the error between measured and predicted values were acceptable for the monitoring BP. We tested PTT-BP models 1 month after the identification without further calibration. Models could predict the BP and the errors between measured and predicted BP were about 5mmHg. The suggested system is expected to be helpful in recognizing any danger during exercise.

• Journal of Sensor Science and Technology
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• v.26 no.4
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• pp.239-244
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• 2017

Noninvasive, cuffless, and continuous blood pressure (BP) monitoring is essential to prevent and control hypertension. A well-known existing method for this measurement is pulse transit time (PTT), which has been investigated by many researchers as a promising approach. However, the fundamental principle of the PTT method is based on the time interval taken by a pulse wave to propagate between the proximal and distal arterial sites. Consequently, this method needs an independent system with two devices placed at two different sites, which is a problem. Even though some studies attempted to synchronize the system, it is bulky and inconvenient by contemporary standards. To find a more sensitive method to be used in a BP measurement device, this study used radial electrical bioimpedance (REB) as a potential indicator for BP determination. Only one impedance plethysmography channel at the wrist is performed for demonstrating a ubiquitous BP wearable device. The experiment was evaluated on eight healthy subjects with the ambulatory BP monitor on the upper arm as a reference. The results demonstrated the potential of the proposed method by the correlation of estimated systolic (SBP) and diastolic (DBP) BP against the reference at $0.84{\pm}0.05$ and $0.83{\pm}0.05$, respectively. REB also tracked the DBP well with a root-mean-squared-error of $7.5{\pm}1.35mmHg$.

• The Journal of Korean Academic Society of Nursing Education
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• v.13 no.1
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• pp.95-104
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• 2007

연구목적: 고혈압환자의 효과적인 자가관리 간호중재를 개발하는데 필요한 기초자료로 혈압자가측정(self-monitoring of blood pressure)에 대한 특성, 장점, 범위 및 제한점을 파악한다. 연구방법: 1996년부터 2005년까지 PubMed에 수록된 고혈압환자의 자가관리 방법중 혈압자가측정방법이 포함된 외국의 연구를 중심으로 체계적인 고찰을 실시하였다. 전체 69개 자가관리방법을 적용한 논문 중에서 혈압자가측정이나 가정에서의 혈압측정(home monitoring)에 대한 45개 논문을 선정하여 분석하였다. 연구결과 전반적으로 혈압자가측정 방법은 고혈압환자의 혈압조절을 향상시키는 효과가 유의한 것으로 나타났다. 환자가 혈압을 자가측정한 방법에서 평균 혈압, 수축기 혈압, 맥압이 유의하게 감소한 것으로 보고되었다. 장기적 프로그램에서 혈압조절율이 향상되거나, 이완기혈압의 감소효과도 보고되었다. 혈압자가측정의 기준치는 연구마다 일치하지는 않았지만 135/85mmHg 수준이 정상혈압의 상한수준으로 제시되었다. 일부 연구에서는 가정 내 혈압측정이 24시간혈압측정을 대체하는 방법으로 추천되었다. 보다 정확한 혈압자가측정을 위해서 신뢰성 있는 혈압측정기구의 사용과 정확한 측정방법이 환자들에게 교육될 필요가 있다. 결론: 혈압자가측정은 고혈압환자의 혈압조절에 유용한 방법으로 고찰되었다. 또한 고혈압의 진단, 혈압치료와 고혈압 약물복용 행위를 향상시키는 교육적 효과도 긍정적으로 나타났다. 따라서 고혈압환자를 위한 효과적인 자기조절프로그램에 혈압자가측정법을 포함하는 것이 추천되며, 추후 한국에서 시도된 관련 연구에 관한 문헌고찰의 비교연구가 필요하다.

• Journal of Biomedical Engineering Research
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• v.27 no.1
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• pp.1-5
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• 2006

In this paper, we propose a subject-independent regression model to estimate systolic blood pressures (SBP) conveniently and continuously. There have been several researches on estimating SBP with pulse transit time (PTT) and they showed promising results. However, previous studies used only PTT as the estimation parameter, and their models were generated with just one person's PTT data which is not applicable to estimating other person's SBP. Therefore, we collected several additional biometric parameters with 202 healthy subjects. After statistical analysis of measured biometric parameters with SBP, we chose final estimating parameters including PTT to generate a multiple linear regression model for estimating SBP. Comparing the results of our study with approvable standards of automated sphygmomanometers developed by Association for the Advancement of Medical Instrumentation and approved by American National Standards Institute (ANSI/AAMI) indicates that our proposed method for continuously blood pressures monitoring gives an acceptable error.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2434-2441
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• 2015

This paper proposes an exercise recommendation system for treating obesity that provides systematic recommendations for exercise and diet. Five body indices are considered as indicators for recommend exercise and diet. The system also informs users of prohibited foods using health data including blood pressure, blood sugar, and total cholesterol. To maximize the utility of the system, it displays recommendations for both indoor and outdoor activities. The system is equipped with multimode sensors, including a three-axis accelerometer, a laser, a pressure sensor, and a wrist-mounted sensor. To demonstrate the effectiveness of the system, field tests are carried out with three participants over 20 days, which show that the proposed system is effective in treating obesity.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.501-504
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• 2006

The estimation of the work of heart can be treated as one of the most important parameters for determining the amount of circulating blood needed for harmonious metabolism in the human body. By monitoring the work of heart, one can detect increased work load of heart and start the treatment at the early stage of CHF. Thus it is necessary to estimate the work of heart. The contractility of the left ventricle, the second important parameter for representing the motion of heart, can be estimated through information on the work of heart. In this study, the modified Windkessel model, which has been used for a measure of vascular hemodynamic impedance parameters, was adapted to estimate the work of heart.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.315-318
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• 1997

The ECG-NIBP patient monitor consist of Noninvasive Blood Pressure(NIBP) module that have micro controller inside. This module transfer data by serial communication to the main processor. This system apply the fuzzy inflating method to reduce the blood pressure measuring time, and moving artifact removing algorithm, several parameters used or more accurate measurement. The ECG monitor use the Digital Signal Processor(DSP) or digital filtering, peak detection, heart rate calculation. This system also offer convenient user interface by rotary key, menu bar. With 7" CRT display, auxiliary TFT LCD display adapted to display information on wide screen.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.12
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• pp.1186-1191
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• 2007

Human driver monitoring system is one of the most important systems for the safety in driving vehicles, and therefore driver assistance system has gained much attention during the last decade. This paper proposed an intelligent driver assistance system which monitors human driver's states from bio-signals such as ECG and Blood Pressure. The proposed system used mamdani fuzzy inference to evaluate the driver's mental strain and generated warning signals to the driver. The approach using bio-signals in driver assistance system is the main issue of the related systems and the preliminary results showed the possibility of further research topics in developing more intelligent embedded systems with bio-signal feedback.