무구속 전극을 이용한 의자형 심전도 모니터링 시스템의 구현 및 평가

노윤홍,정도운,Noh, Yun-Hong,Jeong, Do-Un 한국융합신호처리학회 2015 융합신호처리학회 논문지 (JISPS) Vol.16 No.2

본 연구에서는 현대인들의 일상생활 중 대부분의 시간을 보내는 좌식생활 중에 무구속적으로 장시간 심장활동상태를 모니터링하기 위한 의자형 무구속 심전도 모니터링 시스템을 설계 및 구현하였다. 구현된 시스템은 옷을 입은 상태에서도 측정이 가능하며, 동잡음에도 비교적 강한 장점을 가진다. 이를 위하여 의자의 등받이 부분에 무구속 전극을 배치하였으며, 미세한 생체신호를 증폭하고, 측정 시 발생 할 수 있는 동잡음 및 기저선의 변화, 상용전원에 의한 전원잡음을 제거하기 위하여 증폭기 및 필터를 설계하였다. 또한 제어부와 무선전송부를 구현하여 아날로그 신호를 디지털 신호로 변환하고 생체신호를 PC와 스마트폰으로 전송함으로써 일상생활 중 지속적인 심장활동 상태의 모니터링이 가능하다. 구현된 시스템의 성능을 평가하기 위하여 Ag/AgCl 전극을 사용한 시스템과 비교 실험을 수행하였으며, 실험 결과 구현된 시스템의 무구속적으로 심장활동 상태 모니터링이 가능함을 확인하였다. In this study, we implemented an unconstraint ECG monitoring system on a chair. Nowadays, modern people spend most of their time sitting on the chair. Therefore, it is necessary to have an unconstraint ECG monitoring system that can be used for a long time. The implemented system can perform measurement even with clothes on and it has great advantage on motion artifacts. A pair of unconstraint electrodes are placed on the back of the chair. Amplifier and filters are designed to remove motion artifacts, The baseline noise and power line noise are filtered and very low level of bio-signal is amplified to give a final measurement. Control unit and wireless transmission unit are implemented. Analog signal is converted into digital signal and transmits biological signal to the PC and the smart phone. Therefore continuous ECG monitoring in daily life is made possible. A comparison experiment between Ag / AgCl electrode and unconstraint electrode is conducted to evaluate the performance of the implemented system. As a result, we confirm our unconstraint system can be used for daily life ECG monitoring.

3축 가속도를 이용한 활동상태 분류 시스템 구현 및 알고리즘 개발

노윤홍,예수영,정도운,Noh, Yun-Hong,Ye, Soo-Young,Jeong, Do-Un 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.1

A real time monitoring system from a PC has been developed which can be accessed through transmitted data, which incorporates an established low powered transport system equipped with a single chip combined with wireless sensor network technology from a three-axis acceleration sensor. In order to distinguish between static posture and dynamic posture, the extracted parameter from the rapidly transmitted data needs differentiation of movement and activity structures and status for an accurate measurement. When results interpret a static formation, statistics referring to each respective formation, known as the K-mean algorithm is utilized to carry out a determination of detailed positioning, and when results alter towards dynamic activity, fuzzy algorithm (fuzzy categorizer), which is the relationship between speed and ISVM, is used to categorize activity levels into 4 stages. Also, the ISVM is calculated with the instrumented acceleration speed on the running machine according to various speeds and its relationship with kinetic energy goes through correlation analysis. With the evaluation of the proposed system, the accuracy level stands at 100% at a static formation and also a 96.79% accuracy with kinetic energy and we can easily determine the energy consumption through the relationship between ISVM and kinetic energy.

유비쿼터스 헬스케어를 위한 착용형 심전도 모니터링 시스템 구현

노윤홍,김세진,정완영,정도운 제어로봇시스템학회 2007 제어로봇시스템학회 국내학술대회 논문집 Vol.2007 No.5

일상생활 중 건강모니터링을 위한 착용형 심전도계측 시스템 개발

노윤홍 ( Yun Hong Noh ),정도운 ( Do Un Jeong ) 한국센서학회 2010 센서학회지 Vol.19 No.1

In this study, wearable ECG measurement system was implemented for health monitoring during daily life. A wearable belt-type ECG electrode worn around the chest by measuring the real-time ECG is produced in order to minimize the inconvenience in wearing. The measured ECG signal is transmitted via an ultra low power consumption wireless data communications unit to personal computer using Zigbee-compatible wireless sensor node. The ECG monitoring program is developed at end user which is personal computer. The measured ECG contains many noises mainly due to motion artifacts. For ECG signal processing, adaptive filtering process is proposed which can reduce motion artifacts efficiently and accurately than digital filter. The experimental results show that a reliable performance with high quality ECG signal can be achieved using this wearable ECG monitoring system.

DTW 최소누적거리를 이용한 심전도 이상 검출 알고리즘 구현 및 평가

노윤홍 ( Yun Hong Noh ),이영동 ( Young Dong Lee ),정도운 ( Do Un Jeong ) 한국센서학회 2012 센서학회지 Vol.21 No.1

Recently the convergence of healthcare technology is used for daily life healthcare monitoring. Cardiac arrhythmia is presented by the state of the heart irregularity. Abnormal heart`s electrical signal pathway or heart`s tissue disorder could be the cause of cardiac arrhythmia. Fatal arrhythmia could put patient`s life at risk. Therefore arrhythmia detection is very important. Previous studies on the detection of arrhythmia in various ECG analysis and classification methods had been carried out. In this paper, an ECG signal processing techniques to detect abnormal ECG based on DTW minimum accumulation distance through the template matching for normalized data and variable threshold method for ECG R-peak detection. Signal processing techniques able to determine the occurrence of normal ECG and abnormal ECG. Abnormal ECG detection algorithm using DTW minimum accumulation distance method is performed using MITBIH database for performance evaluation. Experiment result shows the average percentage accuracy of using the propose method for Rpeak detection is 99.63 % and abnormal detection is 99.60 %.

무구속 심탄도 모니터링 시스템을 이용한 스트레스 분석 기초연구

노윤홍 ( Yun Hong Noh ),정도운 ( Do Un Jeong ) 한국센서학회 2011 센서학회지 Vol.20 No.2

Heart related diseases mainly caused by heavy work load and increasing stress in human daily life. Therefore, researches on mobile healthcare monitoring for daily life has been carried out. Notably, wearable healthcare monitoring system which has least restriction has been tried to provide an emergency alert of abnormal heart rate. In this study, we developed chair type unconstrained BCG measurement system which able to perform continuous heart status monitoring at the office and daily life in the unconstrained way. Furthermore, adaptive threshold is used to detect the heart rate from BCG signals. The HRV(heart rate variability) is calculated from heart rate interval. ECG signal measured using conventional method and BCG signal measured using unconstraint system are carried out simultaneously for the purpose of performance evaluation. From the comparison result, BCG signal shows a similar heart beat characteristic as ECG signal. This proves the possibility of practical implementation of unconstraint healthcare monitoring system. In addition, medical examination like valsalva maneuver is performed to observe the changes in HRV due to stress. By performing valsalva maneuver, heart is said to be placed under an artificial physical stress condition. Under this artificial physical stress condition, the time and frequency domain of HRV parameters are evaluated.

무구속 건강모니터링을 위한 심탄도 계측 시스템 구현 및 평가

노윤홍 ( Yun Hong Noh ),정도운 ( Do Un Jeong ) 한국센서학회 2010 센서학회지 Vol.19 No.1

This research proposes measuring of BCG(ballistocardiogram) to monitor heart activities in a non-constrained environment, at home or work. Unlike with ECG, measuring BCG does not require the attachment of leads on the subject`s body and allows signal measuring in a non-constrained state. It enables effective long-term monitoring of cardiac conditions. In this study a chair type BCG measurement system to continuous monitor the activity of the heart is implemented. The instrument consists of upper petal and ready for press of chair load cell sensor is attached to measure the change of the object`s weight. In order to extract the output ballistic signal from the weight and force sensor signals. Beside the signal processing circuit for the digital conversion, the ballistic signal is detected using DAQ equipment. Signal processing algorithm including wavelet transforms for noise cancellation, template matching for normalization and peak detection in BCG is developed. ECG and BCG were concurrently measured to evaluate the performance of the system, and comparing the characteristics of the two signals verified the possibility of the system in non-constrained and non-conscious health monitoring.

다중 압력분포 기반의 착석 자세 분류를 위한 CNN 모델 구현

서지윤,노윤홍,정도운,Seo, Ji-Yun,Noh, Yun-Hong,Jeong, Do-Un 한국융합신호처리학회 2020 융합신호처리학회 논문지 (JISPS) Vol.21 No.2

근골격 질환은 착석 자세로 업무 및 학업을 장시간 진행하거나 잘못된 자세 습관으로 발생하는 경우가 많다. 일상생활에서 근골격 질환을 예방하기 위해서는 실시간 착석자세 모니터링을 통해 잘못된 자세를 바른 자세로 유도하는 것이 가장 중요하다. 본 논문에서는 의자에 밀착된 착석 정보를 무 구속적으로 검출하기 위하여 다채널 압력센서 기반의 자세 측정 시스템과 사용자의 착석 자세 분류를 위한 CNN 모델을 제안한다. 제안된 CNN 모델은 착석 자세 정보를 기반으로 압력분포에 따른 사용자의 5가지 자세 분석이 가능하다. 필드테스트를 통한 자세 분류 신경망의 성능평가를 위하여 10명의 피실험자를 대상으로 분류결과에 대한 정확도, 재현율, 정밀도 및 조화 평균을 확인하였다. 실험 결과, 99.84%의 accuracy, 99.6%의 recall, 99.6%의 precision, 99.6%의 F1을 확인하였다. Musculoskeletal disease is often caused by sitting down for long period's time or by bad posture habits. In order to prevent musculoskeletal disease in daily life, it is the most important to correct the bad sitting posture to the right one through real-time monitoring. In this study, to detect the sitting information of user's without any constraints, we propose posture measurement system based on multi-channel pressure sensor and CNN model for classifying sitting posture types. The proposed CNN model can analyze 5 types of sitting postures based on sitting posture information. For the performance assessment of posture classification CNN model through field test, the accuracy, recall, precision, and F1 of the classification results were checked with 10 subjects. As the experiment results, 99.84% of accuracy, 99.6% of recall, 99.6% of precision, and 99.6% of F1 were verified.

IMU 및 가속도 센서를 이용한 안내견 하네스 행동 알림 시스템 구현

안병구,노윤홍,정도운,Ahn, Byeong-Gu,Noh, Yun-Hong,Jeong, Do-Un 한국융합신호처리학회 2015 융합신호처리학회 논문지 (JISPS) Vol.16 No.1

In this paper, a behavior notification system of the harness of a guide dog is implemented for a blind person to get helps for environmental and situational awareness while walking with the guide dog. IMU modules is attached on the guide dog's harness saddle and the acceleration sensor belt is mounted on its thigh. Gait estimation and behavior judgement are performed by recording and analyzing the outputs of the sensors. Performance analysis for seven different kinds of behaviors has been done. The seven different behaviors, which the guide dog recognizes, are descending stairs, climbing stairs, uphill, downhill, stop, flat road, and selective disobedience. Results for the performance analysis show that the average success rate of the behavior rule estimation of harness of the guide dog is 92.78% and the behavior notification system can be effectively used in real situations. 본 논문에서는 시각장애인이 안내견과 함께 보행 중 환경적 요소와 상황에 따른 인지를 도와주기 위한 안내견 하네스 행동 알림 시스템을 구현하였다. 이를 위하여 안내견의 하네스 안장에 IMU(inertial measurement unit)모듈 및 가속도센서 다리벨트를 장착하였으며, 이로부터 출력되는 정보를 이용하여 안내견의 보폭추정과 자세판단을 수행하였다. 구현된 시스템의 성능을 평가하기 위하여 안내견이 인지하고 있는 자세를 오르막 계단 자세, 내리막 계단 자세, 오르막길, 내리막길 및 평지와 정지 상태로 나누웠으며 시각장애인의 안전을 위한 행동인 불복종명령 상태을 포함한 7가지의 행동에 대한 판별 실험을 수행하였다. 그 결과 안내견 행동 규칙 인식 성공률은 평균 92.78%로 나타났으며, 안내견 하네스 행동알림 시스템의 실제 적용 시 유용성을 확인하였다.

심음을 이용한 실시간 심장 활동 상태 모니터링 시스템 구현

김진환,노윤홍,정도운 한국융합신호처리학회 2018 융합신호처리학회 논문지 (JISPS) Vol.19 No.1

최근 건강에 대한 관심과 욕구가 크게 증가하고 있으며, 이에 따라 스마트 헬스케어 산업이 크게 주목받고 있다. 이로 인해 일상생활 중 자신의 건강 상태를 지속적으로 확인하기 위한 원격의료시스템뿐만 아니라, 최근에는 국내외 기업에서 언제 어디서나 신체의 활동 정보를 계측 할 수 있는 웨어러블 디바이스들을 지속적 으로 연구개발 및 시장에 선보이고 있다. 특히, 맥파와 심전도는 일상생활 중 자신의 건강상태를 지속적으로 모니터링하기 위한 생체신호로 가장 많이 활용되고 있다. 본 연구에서는 마이크 센서를 활용한 심장의 소리 즉, 심음의 계측을 통해 심장 활동 상태 모니터링이 가능한 시스템을 구현하고자 하며, 상용 전자 청진기과 비교평가를 통해 일상생활 중 지속적인 모니터링이 가능함을 확인 하였다. Recently, the smart health care industry has been rising rapidly and interest and efforts for public health have been greatly increased. As a result, the public does not visit medical specialists and medical facilities, but the desire to check their health condition in everyday life is increased. Therefore, many domestic and foreign companies continuously research and develop wearable devices that can measure body activity information anytime and anywhere And the market. Especially, it is used for heart activity measurement device using pulse wave sensor and electrocardiogram sensor. However, in this study, a monitoring system that can detect cardiac activity using cardiac sounds, heart sound measurement rather than pulse wave measurement and electrocardiogram measurement, was performed and its performance was evaluated. Experimental results confirmed the predictability of cardiac heart rate and heart valve disease during daily living.