Preliminary Study on Nonintrusive Measurement of ECG and Respiration while Sitting on a Chair for Human States Estimation

Mieko Ohsuga,Hidenori Boutani 대한인간공학회 2014 대한인간공학회 학술대회논문집 Vol.2014 No.5

The adaptive control of robot’s behaviors depending on human states is important to an affective human-robot interaction. We are trying to detect a decrease in concentration of human who is working or doing something not to make an alarm but to capture opportunity to interrupt without giving nuisance. We conducted an experiment with tasks simulating computer work and confirmed that the measures derived from ECG and respiration change significantly by the degraded concentration. In the present study, we introduced the non-intrusive measurement and conducted similar experiments. For ECG we used the capacity coupled electrodes instead of the electrodes attached on the skin. Chips of conductive tape were attached on the back of the seating face of the chair. The pair of them was used as the electrodes for the differential input of the amplifier. The earth electrode was placed on the seat. Respiration was measured detecting the variations of back pressure by pressure sensors attached to the air bags on the back of chair. Five healthy adults who gave written informed consent participated in the experiment. As a result, respiration was measured successfully for most of the time during computer work for three of five participants. ECG measurement was failed during most periods for one participant who moved or changed postures frequently. R-waves were found during 60-90% period for others. The frequency of body movements or changes of postures caused the differences in the performance of measurement.

플라스틱 광섬유를 이용한 호흡센서의 개발

유욱재,백지윤,조동현,장경원,서정기,허지연,이봉수,조영호,박병기,문주현,Yoo, Wook-Jae,Baek, Ji-Yun,Cho, Dong-Hyun,Jang, Kyoung-Won,Seo, Jeong-Ki,Heo, Ji-Yeon,Lee, Bong-Soo,Cho, Young-Ho,Park, Byung-Gi,Moon, Joo-Hyun 대한의용생체공학회 2009 의공학회지 Vol.30 No.6

In this study, we fabricated a plastic optical fiber based sensor which can monitor the respiration of a patient. The circumference changes of the abdomen were measured using a mirror, a light source and optical detectors because the circumferences of the abdomen could be varied with respiration. The intensity of the reflected lights were measured according to the changes of distance between mirror and plastic optical fiber connected to a light source and a photodiode-amplifier system using a Y-coupler. The respiration signals of fiber-optic sensor system were compared with those of the respiratory and temperature transducers of the $BIOPAC^{(R)}$ system. It is expected that a fiber-optic respiration sensor could be developed for real time respiration monitoring during MRI procedure based on this study.

복부 움직임에 따른 초음파 근접센서를 이용한 호흡측정에 관한 연구

민세동(Se Dong Min),김진권(Jinkwon Kim),신항식(Hang-Sik Shin),윤용현(Young Hyun Yun),이충근(Chungkeun Lee),이정환(JeongWhan Lee),이명호(Myoungho Lee) 대한전기학회 2009 전기학회논문지 Vol.58 No.10

In this paper, we proposed a non-contact respiration measurement system with ultrasonic proximity sensor. Ultrasonic proximity sensor approach of respiration measurement which respiration signatures and rates can be derived in real-time for long-term monitoring is presented. 240 ㎑ ultrasonic sensor has been applied for the proposed measurement system. The time of flight of sound wave between the transmitted signal and received signal have been used for a respiration measurement from abdominal area. Respiration rates measured with the ultrasonic proximity sensor were compared with those measured with standard techniques on 5 human subjects. Accurate measurement of respiration rate is shown from the 50 ㎝ measurement distance. The data from the method comparison study is used to confirm the performance of the proposed measurement system. The current version of respiratory rate detection system using ultrasonic can successfully measure respiration rate. The proposed measurement method could be used for monitoring unconscious persons from a relatively close range, avoiding the need to apply electrodes or other sensors in the correct position and to wire the subject to the monitor. Monitoring respiration using ultrasonic sensor offers a promising possibility of non-contact measurement of respiration rates. Especially, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range of the measurement and quality of the rate-finding for broadening the potential application areas of this technology.

광용적맥파의 신호 패턴을 이용한 호흡 검출 기법

박문수,김정구 한국멀티미디어학회 2016 멀티미디어학회논문지 Vol.19 No.11

A respiration is one of the most useful techniques for vital checking and an abnormal respiration is often the earliest sign of critical illness. Detection of respiration is based on the photo-plethysmography (PPG) with photodiode technique. Because PPG sensor using photodiode can be easily miniaturized, it is suitable for wearable devices. A system to measure respiration rate based on PPG signal is implemented and for a reliable measurement an improved algorithm in accuracy using PPG signal pattern is proposed in this paper. As results regarding to three types of respirations (regular interval, free interval, and weak respiration) the proposed algorithm showed error rate of 0.047, 0.067, and 0.122 respectively.

전기용량성 섬유 압력센서를 이용한 호흡측정 시스템

민세동(Se-Dong Min),윤용현(Young-Hyun Yun),이충근(Chung-Keun Lee),신항식(Hang-Sik Shin),조하경(Ha-Kyung Cho),황선철(Seon-Cheol Hwang),이명호(Myoung-Ho Lee) 대한전기학회 2010 전기학회논문지 P Vol.59 No.1

In this paper, we proposed a wearable respiration measurement system with textile capacitive pressure sensor. Belt typed textile capacitive pressure sensor approach of respiration measurement, from which respiration signatures and rates can be derived in real-time for long-term monitoring, are presented. Belt typed textile capacitive pressure sensor has been developed for this measurement system. the distance change of two plates by the pressure of motion has been used for the respiration measurement in chest area. Respiration rates measured with the textile capacitive pressure sensor was compared with standard techniques on 8 human subjects. Accurate measurement of respiration rate with developed sensor system is shown. The data from the method comparison study is used to confirm theoretical estimates of change in capacitance by the distance change. The current version of respiratory rate detection system using textile capacitive pressure sensor can successfully measure respiration rate. It showed upper limit agreement of 3.7997*10?? RPM, and lower limit of agreement of -3.8428*10?? RPM in Bland-Altman plot. From all subject, high correlation were shown(p<0.0001). The proposed measurement method could be used to monitor unconscious persons, avoiding the need to apply electrodes to the directly skin or other sensors in the correct position and to wire the subject to the monitor. Monitoring respiration using textile capacitive pressure sensor offers a promising possibility of convenient measurement of respiration rates. Especially, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range and quality of the rate-finding, broadening the potential application areas of this technology.

Simplified Structural Textile Respiration Sensor Based on Capacitive Pressure Sensing Method

Se Dong Min,Yonghyeon Yun,Hangsik Shin IEEE 2014 IEEE SENSORS JOURNAL Vol.14 No.9

<P>We propose a simplified structural textile capacitive respiration sensor (TCRS) for respiration monitoring system. The TCRS is fabricated with conductive textile and Polyester, and it has a simple layered architecture. We derive the respiration by the distance changes between two textile plates in the TCRS, which measures the force from the abdominal diameter changes with the respiratory movement. To evaluate the reliability of TCRS, both linearity test and comparison test were carried out. Three times of tensile experiment were performed to confirm the linearity of change in capacitance by the distance change. The result shows that the coefficient of determination (R<SUP>2</SUP>) of proposed TCRS is 0.9933. For comparative study, 16 subjects were participating in the experiment. As a result, the proposed respiratory rate detection system using TCRS successfully measures respiration compared with nasal airflow detection (R = 0.9846, p <; 0.001). In Bland-Altman analysis, the upper limit agreement is 0.5018 respirations per minute and lower limit of the agreement is -0.5049 respirations per minute. From these results, we confirmed that the TCRS could be used for monitoring of unconscious persons, avoiding the uncomfortness of subjects. Monitoring respiration using TCRS offers a promising possibility of convenient measurement of respiration rates. In particular, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products.</P>

Modeling Fresh Produce Respiration and Designing Modified Atmosphere Package

Dong Sun Lee 한국포장학회 2007 한국포장학회지 Vol.13 No.3·4

The method to characterize the fresh produce respiration was presented with possible application of modified atmosphere package design. Particularly the respiration model based on enzyme kinetics was introduced as function of oxygen and carbon dioxide concentrations. The method to estimate the equilibrated package atmosphere for any package conditions was presented by incorporation of O2 and CO2 permeabilities of the packaging film. Temperature dependences for fresh produce respiration and gas permeation were given by Arrhenius equation and then used to analyze the effect of temperature on the package atmosphere. An example analysis was presented for better understanding of the concept.

Long-term characteristics of soil respiration in a Korean cool-temperate deciduous forest in a monsoon climate

엄지영,정석희,천정화,이재호,이재석 한국통합생물학회 2018 Animal cells and systems Vol.22 No.2

Analysis of relationship between soil respiration and environmental factors has become essential for understanding changes in ecosystem carbon cycles under global warming. However, rough predictions have been made that soil respiration will increase with increasing temperature, but long-term data to support this theory were scarce. We measured soil respiration and environmental factors continuously using an automatic open-closed chamber system in a Korean cool-temperate forest from 2004 to 2016 to ascertain the reliability of this prediction and to more accurately predict changes in carbon cycle. Average air and soil temperatures were 11.0°C and 10.2°C. The increase in temperature was greater in winter (the inactive period for soil respiration) than in summer (the active period). Additionally, precipitation decreased sharply because of patter changes in 2012, and through 2016, it was approximately 69% of the previous period. Effect of precipitation on soil respiration was expected to be larger than temperature because the change in precipitation appeared in summer. Soil respiration exhibited a significant decline in 2012 because of precipitation. From 2004 to 2011, it averaged 344.4 mgCO2m−2 h−1 and from 2012 to 2016 the average was 205.3 mgCO2m−2 h−1. This phenomenon hasn’t been detected in short-term studies, suggesting that the prediction of previous studies is inaccurate. Additionally, to predict future ecosystem carbon cycle changes in a cool-temperate monsoon climate, changes in precipitation pattern should be regarded as equally important to temperature, and the prediction cannot be based solely on temperature. Therefore, long-term and continuous measurements are needed with consideration of the effects of both precipitation and temperature.

Development of a Chest‑Belt‑Type Biosignal‑Monitoring Wearable Platform System

Joo‑Hyeon Lee,Hyun‑Seung Cho,Jin‑Hee Yang,Sang‑Min Kim,Jeong‑Whan Lee,Hwi‑Kuen Kwak,Je‑Wook Chae 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

The purpose of this study was to develop a wearable platform system that can detect and acquire a soldier’s biosignals (i.e., heart activity signal, respiration rate, etc.) in a nonrestrained, unconscious manner. These detected biosignals are transmitted to a processing device to analyze and monitor the soldier’s physical status. To achieve this, textile-based heart activity electrodes and a strain gauge sensor for the respiration signal measurement were developed, and their performances in detecting each signal were verifed. These sensors were embedded in a chest belt to design a wearable platform that can simultaneously measure heart activity and respiration signals. The sensor part of the chest belt has a dual layer structure to detect high-quality signals. Stretch fabric was used on the outer layer and a respiration sensor was attached to the belt. On the inside layer, a non-stretch fabric was used as the base fabric and a heart activity-sensing electrode, that is capable of taking measurements using a modifed lead-II heart activity signal induction method, was embroidered onto the fabric. Subjects were asked to wear the chest belt, and a biosignal processor module was attached to verify the system’s performance while simultaneously acquiring the heart activity and respiration signals. More specifcally, it was confrmed that the two signals were detected in a stable. It is expected that the biosignal-monitoring wearable platform system developed in this study will be able to efectively analyze and monitor soldiers’ biosignals.

Development of Clothing-type Wearable Platform System for Biosignal-Monitoring

( Hyun-seung Cho ),( Jin-hee Yang ),( Joo-hyeon Lee ) 한국감성과학회 2022 춘계학술대회 Vol.2022 No.-

The purpose of this study was to develop a wearable platform system that can detect and acquire human’s biosignals (i.e., heart activity signal, respiration rate, etc.) in a non-restrained, unconscious manner. These detected biosignals are transmitted to a processing device to analyze and monitor the physical status. To achieve this, textile-based heart activity electrodes and a strain gauge sensor for the respiration signal measurement were developed, and their performances in detecting each signal were verified. These sensors were embedded in a chest belt to design a wearable platform that can simultaneously measure heart activity and respiration signals. The sensor part of the chest belt has a dual layer structure to detect high-quality signals. Stretch fabric was used on the outer layer and a respiration sensor was attached to the belt. On the inside layer, a non-stretch fabric was used as the base fabric and a heart activity-sensing electrode, that is capable of taking measurements using a modified lead-II heart activity signal induction method, was embroidered onto the fabric. Subjects were asked to wear the chest belt, and a biosignal processor module was attached to verify the system’s performance while simultaneously acquiring the heart activity and respiration signals. As a result, it was confirmed that the two signals were detected in a stable. It is expected that the biosignal-monitoring wearable platform system developed in this study will be able to effectively analyze and monitor biosignals.