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Instrument with a Tele-Reporting Device for Telemedicine and Telecare. Jae Min Kang, Student Member, IEEE, Taiwoo Yoo, and Hee Chan Kim, Member, IEEE.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 55, NO. 5, OCTOBER 2006

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A Wrist-Worn Integrated Health Monitoring Instrument with a Tele-Reporting Device for Telemedicine and Telecare Jae Min Kang, Student Member, IEEE, Taiwoo Yoo, and Hee Chan Kim, Member, IEEE

Abstract—In this paper, the prototype development of a wrist-worn integrated health monitoring device (WIHMD) with tele-reporting function for emergency telemedicine and home telecare for the elderly is reported. The WIHMD consists of six vital biosignal measuring modules, which include a fall detector, a single-channel electrocardiogram, noninvasive blood pressure, pulse oximetry (SpO2 ), respiration rate, and body surface temperature measuring units. The size of the WIHMD is 60 × 50 × 20 mm, except the wrist cuff, and the total system weighs 200 g, including two 1.5-V AAA-sized batteries. The functional objective of the WIHMD is to provide information concerning current condition, such as vital biosignals and locational information, with compromised fidelity to experts at a distance through the commercial cellular phone network. The developed system will provide the facility for rapid and appropriate directions to be given by experts in emergency situations and will enable the user or caregiver to manage changes in health condition with helpful treatment. Index Terms—Biosignal measurement, cellular phone network, emergency telemedicine, health monitoring device, home telecare, ubiquitous healthcare.

I. I NTRODUCTION

T

HE PROVISION of healthcare in most countries is facing common problems, namely an aging population, the burden of chronic conditions, the increase of emergency occurrence frequencies, an increase in the associated medical costs, and the lack of efficient health models to provide a satisfactory solution [1]. Of these, the main topic requiring solution is the provision of an effective medical service to the elderly and emergency patients. Due to the aging population in the present era, the requirements for efficient healthcare for the elderly and the associated healthcare cost burden are increasing. In fact, the cost of care for those aged over 65 at present is more than ten times that for individuals aged between 16 and 64 years. Moreover, elderly

Manuscript received October 6, 2004; revised May 5, 2006. This work was supported in part by the Korea Science and Engineering Foundation through the Bioelectronics Program of the Specified R&D Grants from the Ministry of Science and Technology. This paper was presented in part at the 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, San Francisco, CA, September 1–4, 2004. J. M. Kang and H. C. Kim are with the Department of Biomedical Engineering, College of Medicine, Seoul National University, Seoul 110-744, Korea (e-mail: [email protected]). T. Yoo is with the Department of Family Medicine, College of Medicine, Seoul National University, Seoul 110-744, Korea. Digital Object Identifier 10.1109/TIM.2006.881035

people consume a high proportion of healthcare services, and in the future, this proportion is likely to rise considerably [2]. In addition, emergency occurrence frequency related to the elderly or patients at risk of potentially critical events is also increasing. In emergency situations, it has always been recognized that promptness and the appropriateness of treatment are the most critical factors. Recent studies have shown that early and specialized prehospital management contributes to emergency case survival. The prehospital phase of management—in particular, accurate triage to direct the patient to the closest most appropriate facility—is of critical importance [3]. One possible solution to the problem of delivering efficient care to an aging population and patients in potential emergency environments is to introduce telemedicine and telecare by combining health state monitoring devices with tele-reporting functionality. To provide an effective care service, it is necessary to develop a mobile patient monitor with a tele-reporting function. Existing patient monitoring devices have been used extensively in many areas of healthcare, from the hospital intensive care unit (ICU) to care at home [4]. Although commercialized patient monitors provide high fidelity data, and many facilities are using them, they are limited from the user’s perspective. 1) They are inconvenient, that is, they are bulky and need to be connected to several electrodes to measure various vital biosignals. 2) They have poor mobility and restrict usage in hospitals or indoors. 3) They are relatively expensive to be used all the time and by people who cannot afford them. Due to these limitations, existing patient monitoring systems are unsuitable when monitoring has to be accomplished over periods of several weeks or months, as is the case for the elderly and patients at risk of potentially critical events. An integrated portable telemedicine system would benefit the elderly and patients in critical life conditions by providing a periodic health condition monitoring and a rapid response capability in emergency situations based on information exchange between a patient and a professional. This type of system will undoubtedly result in reduced mortality and dramatically improve patient outcomes. It will benefit not only individual users but also eventually the whole community by reducing total healthcare costs. In this paper, we describe a wrist-worn integrated health monitoring device (WIHMD) with tele-reporting function for emergency telemedicine and home telecare. Our strategy is that every possible vital biosignal instrument is built into a wristworn unit, and a central processor supervises the operation of

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Fig. 1. Functional block diagram of the WIHMD system.

Fig. 3.

Fig. 2. Schematic drawing of the prototype WIHMD.

each component, analyzes the measured data, and then rapidly communicates with the patient’s caregivers, such as doctors or relatives, through a connected telecommunication device. Thus, it is possible to get rapid and appropriate directions made to handle emergency situations and to enable the user or caregiver to detect and manage changes in the user’s health. The technical challenge in the development of such a device is not only to integrate several health monitoring devices into a small wrist-wearable unit but also to make the system practical for healthcare service that is reliable under various operating conditions, easy to operate and manage, and affordable for most possible users. Ultimately, the WIHMD will enhance the quality of life for the elderly and patients in potential emergency environments. II. M ATERIALS AND M ETHODS A. System Description The WIHMD consists of six vital biosignal measuring modules, which include a fall detector, single-channel electrocardiogram (ECG), noninvasive blood pressure (NIBP), pulse oximetry (SpO2 ), respiration rate, and body surface temperature (BST) measuring units. As shown in Fig. 1, the central unit of a microcontroller (ATmega103L, Atmel, USA) with 128 KB of in-system programmable flash, 4 KB SRAM, and programmable serial universal asynchronous receiver transmitter (UART) manages the operation of each measurement module and evaluates the patient state by collecting and analyzing the measured data. As shown in Fig. 2, the hardware of the actual device is made of a wrist cuff for the NIBP measurement and a main unit mounted on the cuff. Two textile electrodes for ECG and a semiconductor temperature sensor are

Photograph of the developed WIHMD worn on the wrist.

attached to the inner surfaces of the cuff, and a finger cliptype SpO2 sensor is connected to the main unit. Fig. 3 shows a picture of the developed system worn on the wrist. It also contains two printed circuit boards, which include analog and digital circuitry and other onboard sensors. The size of the WIHMD is 60 × 50 × 20 mm, excepting the wrist cuff, and the total system weighs 200 g, including two 1.5-V AAA-sized batteries. The total power consumption is about 150 mA with 3-V supply voltage in active mode, where all measuring modules are in operation and about 5 mA in idle mode with only the fall detector in operation. The software of WIHMD was developed for operational simplicity and efficiency. Considering the fact that the possible users are relatively old and infirm, any complicated user interface would be counterproductive in daily life or in emergency situations. The WIHMD provides relatively large graphic icons on a 128 × 64 pixel graphic LCD and three input buttons as user interface and connects with public telecommunication devices, like cellular phones, in a wireless manner. When it is ordered to do so, the microcontroller wakes up from a power-saving mode and digitizes the analog output of each measurement module through its imbedded A/D converter with 10-bit resolution and 100-Hz sampling rate. In emergency telemedicine mode, the WIHMD starts to operate either if it automatically detects the emergency occurrence, mainly based on the fall detector output, or if the wearer presses any button for longer than 5 s when he/she feels something is wrong. In this mode, the WIHMD performs all measurements and sends the measured data to preassigned caregivers as quickly as possible. The characteristics of each measurement module and telecommunication device are given below. B. Measurement Module and Telecommunication Device Description 1) Fall Detector: Falls are one of the greatest obstacles to independent living for frail and elderly people. People of all

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ages fall, but these accidents rarely cause injury for the younger members of society; however, among the elderly population, they are often much more serious. Perhaps half of all falls in older people result in minor soft-tissue damage, but 10%–15% cause serious physical injury [5]. So, early detection is an important step in providing elderly people with the reassurance and confidence necessary to maintain an active lifestyle. It is known that a combination of an accelerometer and a gyroscope must be used to accurately detect the different kinds of falls [6]. We developed a simple fall detector using a two-axis accelerometer (MMA3201, Motorola, USA) and a in-house-made posture sensor that is basically composed of a photo-interrupter with a pendulum. As a result of a pendulum swing, a photo-interrupter acts as an ON–OFF switch to indicate the wearer’s wrist orientation with respect to gravity. The fall detection scheme is as follows. First, the system is in idle mode to minimize power consumption. If peak acceleration exceeds a predetermined threshold, the comparator output wakes up the system into active mode. Then, after 1 s, the central processor unit turns on the posture sensor and reads its output for the next 1 s. If the output of the posture sensor indicates that the subject’s lower arm is laid on the ground, the central processor unit determines an occurrence of fall; otherwise, it just returns to idle mode. Using this relatively simple operational scheme, we achieved a remarkable reduction in the number of false positive alarms caused by vehicle (elevator, car, etc.) riding or brisk motions of arm and so on. Since almost all emergency situations are accompanied by a fall, the fall detector remains active all the time and is crucially used to detect emergency onset. When the WIHMD detects a fall event, it confirms whether the wearer is conscious or not by raising a sound alarm. Then, if there is no response from the wearer in a given time (10 s), the WIHMD starts the vital biosignal measurements and provides the emergency occurrence to preassigned caregivers with the appropriate information. 2) Single-Channel ECG: ECG is widely used as one of the most simple and effective methods of continuously monitoring the heart for tele-healthcare and conventional medical care. For ECG measurement on the wrist, we used only two textile electrodes for a single channel (Lead I), which record the ECG between each arm. The textile electrodes are made of a conductive sheet, which has a surface resistance of 0.05–0.1 Ω/cm2 . One textile ECG electrode for the left arm is attached to the inner surface of the wrist cuff, and the right hand must touch the other electrode at the outer layer of the cuff. The analog circuitry of the ECG module consists of an instrumentation amplifier, a notch filter, and a noninverting amplifier with a total gain and bandwidth of 80 dB and 40 Hz, respectively. The ECG signal is converted into a digital signal with sampling rate of 100 Hz for heart rate (HR) estimations. 3) NIBP: Abnormal blood pressure is the most powerful cardiovascular risk factor. Regular blood pressure monitoring at home in free living conditions is helpful in the management of cardiovascular diseases [7]. The accumulated NIBP data over an extended period can be used to evaluate a patient’s health and indicate the time for medical treatment. In this study, a conventional digital wrist sphygmomanometer was developed.

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The NIBP module was constructed using a motor, pump, solenoid valve, and wrist cuff from a commercialized product (SE-309, Sein Inc., Korea) and a small semiconductor pressure sensor (MPXM2053, Motorola, USA). All electronic circuitry and the program for oscillometric pressure measurement were developed in this laboratory [8]. 4) SpO2 : Pulse oximetry is a noninvasive method of monitoring the arterial oxygen saturation level based on Beer’s law for the absorption of light by hemoglobin and oxyhemoglobin. The pulse oximeter makes use of the pulsatile components of arterial blood’s absorbance values at two different wavelengths. We used red (660 nm) and infrared (940 nm) light emitting diode (LED) as the incident light source. The reflected light is recorded by a photodetector, and variations in light intensity are caused by changes in flow and pressure pulsations in blood. Then, the SpO2 value is calculated from the level of variations in light intensity in each channel (Red, IR). For this system, a SpO2 module was developed using a commercial finger clip sensor (8000H, NONIN, USA) connected to the main unit, which includes the required electronic circuitry and program. 5) Respiration Rate: In patients with chronic obstructive pulmonary diseases and sleep apnea, it is important to evaluate the extent of obstruction of the respiratory system; regular testing is often useful in this regard [9]. Long-term ambulatory recording of respiration can provide more extensive and specific information about the occurrence of abnormal patterns of breathing. In this study, respiration rate was estimated from the R–R interval variation curve, which is the only possible way under the limitation that the measuring position is restricted to the wrist. First, we calculate the R–R interval between each beat from the ECG waveform using the QRS detection algorithm. After rejecting false detection of the QRS peak using the mean time interval threshold, we acquire the R–R interval variation curve. Then, the respiration rate is calculated using the baseline crossing algorithm [10]. 6) BST: Central body temperature is one of the basic factors that reflect homeostasis, and it can indirectly tell whether a patient’s condition has worsened or whether the temperature of the patient’s environment has changed. BST, as determined from wrist skin, is quite different from the central body temperature but can be used to detect changes in a patient’s environmental or physiological state. In the developed system, the BST module was fabricated using an IC-type temperature sensor (TC1047, Microchips, USA). It is small in size, low cost, consumes little power, and is highly accurate. The sensor is attached to the inner surface of the wrist cuff with its sensing surface contacting the skin. 7) Tele-Reporting Device: The tele-reporting device is an essential part of telemedicine or tele-healthcare systems like WIHMD. In the case of emergency telemedicine, it must rapidly transfer the information acquired by the instrument to caregivers. In home telecare for the elderly, such a rapid transfer is not necessary, but transferring the measured data to a centralized server or doctor’s personal computer is still required for later examination by healthcare services. Nowadays, many kinds of wireless communication devices are available,

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TABLE I SUMMARY OF PERFORMANCE EVALUATION RESULTS

e.g., Bluetooth, wireless local area network (LAN), radio frequency (RF) transceiver, and a cellular phone. In our previous research, we compared the telecommunication methods to be used with a chest strap type of patient monitoring device for emergency telemedicine system (ETS) [11]. Based on the results of the previous study and considering the system complexity, power consumption, and reliability, we chose an RF transceiver and a cellular phone for short- and long-range telecommunications, respectively. In the developed system, tele-reporting was accomplished in two separate ways. The first involved an RF link between the WIHMD and a cellular phone for short-range transmission. The second involved the transmission of information to remote caregivers and/or a server computer through the commercial cellular phone network. We used TXM-LC and RXM-LC (433 MHz, 10 mW, FM, LINX tech, USA) as RF transmission and reception modules, respectively; the latter is connected to a cellular phone (IM-3000, SK Teletech, Korea) via an RS-232 connection with 38400-Bd rate. III. R ESULTS

Fig. 4. Screen display of the data acquisition program for the performance evaluation test.

A. Performance Evaluation Prior to practical application, we evaluated the performance of each measurement module using commercialized simulators and a test setup and by human trial as summarized in Table I. Except the human trial cases, the transducers or electrodes of the WIHMD were directly connected to the simulators or the test setup. Fig. 4 shows a screen display of the data acquisition program used for the performance evaluation test and system debugging. This program consists of one data block in which the measured parameters and patient information are shown and three waveform blocks for SpO2 , ECG, and oscillatory cuff pressure of NIBP measurement. Performance evaluation of the developed ECG module was accomplished using a commercial ECG simulator (PatientSimulator 214B, DNI Nevada Inc., USA) [12]. For various simulated ECG outputs with range of 40–240 bpm, the developed ECG module produced HR outputs for normal waveforms within a mean error of ±1%. The performance of the developed NIBP module was verified using a commercial simulator (BPPump2M, BIO_TEK, USA) [13]. For all simulator outputs

Fig. 5. Respiration rate detection using R–R interval variability. (Above) Real respiration waveform using a spirometer. (Below) Extracted respiration waveform from R–R interval variability.

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TABLE II USER NEEDS ANALYSIS OF THE HEALTH MONITORING DEVICE FOR EMERGENCY TELEMEDICINE AT FOUR DIFFERENT SITUATIONS

for wrist measurement, the developed NIBP module provided outputs within an error range of ±5 mmHg. In the case of the SpO2 module, we used a commercial SpO2 simulator (Oxitest plus7, DNI Nevada Inc., USA) for evaluation [14]. Over various ranges of SpO2 levels, the output showed an accuracy within an error range of ±2%. In a performance evaluation study, the respiration rate was simultaneously measured using a commercial spirometer (WebDoc Spiro, Elbio Company, Korea) as a reference. In Fig. 5, the upper plot shows the respiratory signal of the spirometer, while the bottom plot shows the extracted respiratory signal as the R–R interval variability from the ECG. Extensive comparative tests showed that the respiratory signal by R–R interval variability was highly correlated with the real respiration rate. However, the R–R interval variation is affected by many physiologic or emotional factors other than respiration. In addition, since the respiratory signal is sampled by each heartbeat, the extracted respiratory signal showed a low correlation with the actual over the range of 8–18 breaths/min [10]. For the evaluation of the BST module, the developed module was tested inside a heated chamber at temperatures that were incremented over the range of 25 ◦ C to 40 ◦ C in 1 ◦ C steps. The results showed good linearity and an accuracy within a mean error of ±1.5%. For the evaluation of the fall detector, a total of 150 simulated cases were tested. Five human subjects were asked to try three different types of movements, namely 1) fall while walking, 2) fall while standing, and 3) sit from standing with ten times repetition of each. Our fall detection algorithm based on twostage checking of the posture after the falling acceleration signals provided a good detection rate of over 90%. Table I summarizes the results of the performance evaluation. B. Application to Emergency Telemedicine The functional objective of the WIHMD with respect to emergency telemedicine is to provide patient health information, such as vital biosignals and locational information, to the nearest emergency service center in a form that allows rapid and appropriate expert response. We analyzed four possible emergency scenarios in which the device would be useful; Table II summarizes the results. In the emergency telemedicine mode, the WIHMD starts to operate as soon as it automatically detects an emergency occurrence using its built-in fall detector or when the user

activates the device by pressing the emergency button. Once an emergency has been detected, the main control unit sends an emergency alarm and the patient’s health information through the connected cellular phone using the short messaging service (SMS), which is basically a text transmission service provided by the cellular phone company. In this study, we transferred six parameters, i.e., HR, respiration rate, blood pressure, SpO2 , BST, and the location of the user as represented by the mobile phone service base station ID. The advantages of the peerto-peer SMS model are the rapid and safe transmission of text messages without having to establish a centralized largescale service system. Furthermore, it is possible to assign multiple receivers, including doctors or family members, so that interested parties may receive the message simultaneously. In addition, recently, mobile phones are being equipped with a global positioning system (GPS), which can directly guide the rescue team to the precise emergency location [11]. Due to the difficulty in applying the developed WIHMD to real emergency situations, we attempted to simulate emergency situations and evaluated the performance of the system. Three volunteer subjects were asked to wear the WIHMD for 16 h a day during waking hours and were asked to make three manual emergency alarms and three simulated falls per day. Fig. 6 shows the test result of the emergency telemedicine application. Fig. 6(a) shows typical accelerometer and posture sensor waveforms with parameters and events used in the fall detection algorithm, while Fig. 6(b) shows a screen display of the emergency event-logging program during this testing. This program shows the logged emergency events with records of the patient information (ID, name, and age), the measured physiological values, event type, and position/location ID. In real applications, a cellular phone was wirelessly connected to the WIHMD and sent emergency messages and health information to other designated cellular phones shown on the right-hand side in Fig. 7. All subjects felt comfortable wearing the device for 16 h. All manually activated and simulated events were successfully detected, and the preassigned recipient cellular phone received messages correctly. IV. C ONCLUSION We have developed a WIHMD for use in emergency telemedicine and home telecare for the elderly. The unit was designed to provide tele-healthcare services for high-risk patients

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Fig. 6. Test results for the emergency telemedicine application. (a) Typical waveforms of the accelerometer and the posture sensor for the simulated fall. (b) Screen display of the emergency event-logging program.

Fig. 7. Photograph of the cellular phone connected to the developed WIHMD and SMS display on the receiver’s cellular phone in the emergency telemedicine application.

and the solitary elderly at “any time/any place” in an unconstrained fashion, in other words, ubiquitous healthcare services. The transmitted vital information comprises six physiological parameters and variables, namely 1) fall detection, 2) singlechannel ECG, 3) arterial blood pressure, 4) SpO2 , 5) respiration

rate, and 6) BST. The tele-reporting function of the WIHMD was realized by wireless connection to a cellular phone. All test results confirm the applicability of the WIHMD to both emergency telemedicine and home telecare. A shortcoming of the WIHMD is the limited fidelity of the measured biosignals due to the limited body contact with an area of the wrist. If we could measure biosignals at other sites, such as the chest, waist, and ankle, and connect such distributed measurement modules using a so-called personal area network (PAN), then more and higher fidelity biosignals would be acquired. Bluetooth will be a more promising and stable solution in this case because it has encryption, security, low power consumption, ad hoc networking, and works at short range [11]. Furthermore, a Bluetooth mobile phone is now available, which will be a practical solution for the central unit of a PAN. In this preliminary study, we demonstrate that the developed WIHMD provides convenient and comfortable multiparameter health monitoring for a period of weeks or months or even continuous monitoring in a very cost-effective manner with

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acceptable fidelity and reliability. With some modification and a better fitting for individual applications, the WIHMD will ultimately enhance the quality of life for the elderly and those patients at risk of requiring emergency treatment. R EFERENCES [1] F. Castanie, C. Maihes, and M. Ferhaoui, “The U-R-Safe project: A multidisciplinary approach for a fully ‘nomad’ care of patients,” in “IST Project Report,” IST-2001-33352, 2002. [2] K. Doughty, K. Cameron, and P. Garner, “Three generations of telecare of the elderly,” J. Telemed. Telecare, vol. 2, no. 2, pp. 71–80, Jun. 1996. [3] B. Meade, “Emergency care in a remote area using interactive video technology: A study in prehospital telemedicine,” J. Telemed. Telecare, vol. 8, no. 2, pp. 115–117, Apr. 2002. [4] W. G. Scanlon, N. E. Evans, G. C. Crumley, and Z. M. McCreesh, “Lowpower radio telemetry: The potential for remote patient monitoring,” J. Telemed. Telecare, vol. 2, no. 4, pp. 185–191, Dec. 1996. [5] K. Doughty, R. Lewis, and A. McIntosh, “The design of a practical and reliable fall detector for community and institutional telecare,” J. Telemed. Telecare, vol. 6, suppl. 1, pp. 150–154, Feb. 2000. [6] B. Najafi and K. Aminian, “Measurement of stand-sit and sit-stand transitions using a miniature gyroscope and its application in fall risk evaluation in the elderly,” IEEE Trans. Biomed. Eng., vol. 49, no. 8, pp. 843–851, Aug. 2002. [7] I. B. Aris, A. A. E. Wagie, and N. B. Mariun, “An Internet-based blood pressure monitoring system for patients,” J. Telemed. Telecare, vol. 7, no. 1, pp. 51–53, Feb. 2001. [8] J. H. Park, J. M. Kang, and H. C. Kim, “Development of a digital wrist sphygmomanometer for emergency use,” in Proc. ICBME, 2002, pp. 181–183. [9] C. Ruggiero, R. Sacile, and M. Giacomini, “Home telecare,” J. Telemed. Telecare, vol. 5, no. 1, pp. 11–17, Mar. 1999. [10] P. Z. Zhang, W. N. Tapp, S. S. Reisman, and B. H. Natelson, “Respiration response curve analysis of heart rate variability,” IEEE Trans. Biomed. Eng., vol. 44, no. 4, pp. 321–325, Apr. 1997. [11] D. G. Park and H. C. Kim, “Comparative study of telecommunication methods for emergency telemedicine,” J. Telemed. Telecare, vol. 9, no. 5, pp. 300–303, Sep. 2003. [12] Specification of PS214B. last checked 22 April 2006. [Online]. Available: http://www.mtk-biomed.com/03_produkt/_PDF/englisch/214_e.pdf [13] Specification of BPPUMP2M. last checked 22 April 2006. [Online]. Available: http://us.fluke.com/usen/products/specifications.htm?cs_id= 34927(FlukeProducts)&category=FB-SIMS(FlukeProducts) [14] Specification of Oxitest Plus7. last checked 22 April 2006. [Online]. Available: http://www.demaco-ben.nl/01c2c9944712bfa04/ spo2simulator/specifications/index.html

Jae Min Kang (S’01) received the M.S. degree in biomedical engineering from Seoul National University, Seoul, Korea, in 2000. He is currently working toward the Ph.D. degree at the Medical Electronics Laboratory (MELab), Seoul National University. Since 2001, he has been with the MELab, Seoul National University. He participated in various national fund projects including “Development of a Ubiquitous Biotelemetry System for Emergency Care,” “Development of a Intelligent Robot for Supporting the Human Life,” and “Development of a Core Technology of Silver Medical Instrument for the Elderly.” His interests include patient monitoring technology, emergency telemedicine, and the wireless portable healthcare system. Mr. Kang is a Student Member of the Korea Society of Medical and Biological Engineering and IEEE/EMBS.

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Taiwoo Yoo received the M.D. and Ph.D. degrees from Seoul National University, Seoul, Korea, in 1980 and 1989, respectively. From 1980 to 1984, he completed family practice residency and fellowship with the Department of Family Medicine, Seoul National University Hospital. From 1984 to 1989, he again finished residency and fellowship with the Department of Family Medicine, Case Western Reserve University, Cleveland, OH, and Bowman Gray School of Medicine. Since 1990, he has been a faculty member with the Department of Family Medicine, Seoul National University Hospital, where he is currently a Professor and Chairman. His research interest is mobile telecare and e-health. He has granted with major telemedicine projects from the government several times.

Hee Chan Kim (M’95) received the Ph.D. degree in control and instrumentation engineering (biomedical engineering major) from Seoul National University, Seoul, Korea, in 1989. From 1982 to 1989, he was a Research Member with the Department of Biomedical Engineering, Seoul National University Hospital. From 1989 to 1991, he was a Staff Engineer with the Artificial Heart Research Laboratory, University of Utah, Salt Lake City, working on a National Institute of Healthfunded electrohydraulic total artificial heart project. In 1991, he joined the faculty of the Department of Biomedical Engineering, College of Medicine, Seoul National University, where he is currently a Professor. From 1993 to 1994, he was a Visiting Professor with the Department of Pharmaceutics and the Artificial Heart Research Laboratory, University of Utah. He is currently leading the Medical Electronics Laboratory, Seoul National University, where his major research activities are the development of biomedical systems with special interests in electronic instrumentations, biosensors, and microsystems for the ubiquitous healthcare system. In these areas, he has published over 73 peer-reviewed scientific papers in international journals. Dr. Kim is a member of the Korea Society of Medical and Biological Engineering, IEEE/EMBS, and the American Society of Artificial Internal Organs.