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This paper is a part of research which is focused on the development of the convenient device for continuous non-invasive monitoring of arterial blood pressure by noninvasive and non-oscillometric way. Potentially useful parameter for continuous monitoring of blood pressure could be the pulse wave velocity between different regions of human body. It has been demonstrated that systolic blood pressure estimation from this parameter is possible with acceptable accuracy by personal calibration of the method for particular patient. However, most of previous studies are focused on utilizing such measurement on patients in critical conditions; the data of experiments with healthy subjects are quite limited. The blood pressure estimation method is based on a presumption that there is a singular relationship between the pulse wave velocity in arterial system and blood pressure. The measurement of pulse wave velocity involves the registration of two time markers, one of which is based on ECG R peak detection and another on the detection of pulse wave in peripheral arteries. As a result of current study it is shown that with the correct personal calibration it is possible to estimate beat-to-beat systolic arterial blood pressure with comparable accuracy to conventional noninvasive methods.

During nearly one hundred years developments, the discharge wave-shapes of the defibrillator was improved from the AC to DC, from monophasic to biphasic. The truncated decaying exponential wave-shape has become the standard for implantable cardiac defibrillators (ICD) now and has been adopted by more and more automatic external defibrillators (AED). The defibrillation energy was decreased distinctly through these improvements. The low energy defibrillation has several superiorities: ➀ alleviating the shock harmfulness to the body, ➁ lighting the mental pressure of the sufferer, ➂ prolonging the battery’s life of ICD. So the investigation on decreasing the defibrillation energy is very important. The mechanism of ventricular defibrillation is the shock electric field interacts with myocardium cells are not in absolute refractory and enforces these cells depolarizing and turning into refractory period. Then this myocardium cannot response the new stimulation from the other myocardium excitation. Lf there are enough myocardium cells being in refractory period, the ventricular fibrillation will stop. The goal of our research is decreasing the defibrillation energy markedly. We started with improving the wave-shapes and the current distribution of the defibrillator discharge. A multifunctional defibrillator for research has been designed and built to realize this goal. Several results have been obtained after a total of seven animal trials. During the animal trials, one of the discharge electrodes was put into the right ventricle transvenous and the other electrode was affixed to the left thorax’s surface. The minimum Vf defibrillation energy threshold is 1.5J, and the average VF defibrillation energy threshold is 7.5±5J. The minimum VF defibrillation voltage threshold is 250V, and the average VF defibrillation voltage threshold is 360±100V. The minimum VF defibrillation threshold of amounts of electric charge is 0.006C, and the average VF defibrillation threshold of muounts of electric charge is 0.03±0.01C.

We propose a technique that integrates pnjunction light emitting diodes and Schottky diode photo detectors operating in the visual spectrum (450 – 750nm) in a CMOS process that will output results to an RFID system. This technique relies on known absorption and scattering functions in the epidermis, dermis and subcutaneous tissues for diabetic diagnoses. The suggested wristwatch-type system consists of an arrays of pn-junction diode for emitting light, CMOS Schottky diodes for detecting light, a signal processing unit, a warning signal generation unit, and an RFID chip with antennae. The main features of this system are monitoring the glucose level by anon-invasive and continuous manner and a wireless communication between the device and an RFID reader, which also has an ability to make a phone call. When the glucose level reaches a critical level, the patient receives a warning signal, and, at the same time, the reader calls an emergency number automatically. Due to the low fabrication cost, the suggested system can be inexpensively manufactured so that it can be used for in-home monitoring of the glucose level of a patient. Additional post-processing may be required to calibrate the device to account for variations in epidermal properties between individual patients. The future extensions of this device can be applied to cardiac and temperature monitoring mechanisms to be used in a portable health monitoring system.

Prophylactic measures are reducing costs of healthcare without lowering its quality. Telemetric Personal Health Monitoring (TPHM) Systems with multi-parametric sensors allow an active integration of a patient into his treatment.

A common problem in such a system is the verification and identification of the user to guarantee the authenticity of the gathered data.

To assign the measured physiological parameters to the legitimate user we included a gait-based identification algorithm into a TPHM System.

The algorithm records two-dimensional acceleration data from a two-axis accelerometer located on the chest belt. In the configuration mode the participant has to walk fast for one minute to allow the algorithm to calculate a reference pattern for the legitimate user of the belt. In the identification mode the algorithm is looking for fast walking sequences and compares the respective pattern with the reference pattern. Test patterns generated by 4 users wearing the belt were compared to find out if the algorithm is able to distinguish between legitimate and illegitimate users.

Analog acceleration data are sampled at 250Hz for 20 seconds and converted into a two dimensional acceleration diagram. The reference pattern is generated from the three most typical patterns out of five runs by the legitimate user. We use histogram statistics as a simple and performance-efficient way to classify the acquired data, as our goal is to implement our algorithm directly on the chest-belt’s microcontroller.

Cardiovascular diseases are the leading cause of death and disability throughout the world and standard treatment in hospitals or rehabilitation centers remains one of the biggest cost-factors in healthcare. Therefore, the prevention and the secondary-prevention of cardiovascular illnesses are of paramount importance for the entire healthcare system. One possible method of prevention is the continuous telemonitoring of cardiovascular patients. Hence, the authors introduce a research project with the aim of developing a context-aware cardiovascular long-term monitoring system. The system should enable continuous patient-friendly measurements of blood-pressure and electrocardiogram (ECG). Furthermore, the system should allow an objective evaluation of the patient’s physiological parameters taking into consideration context information, such as individual activities and stress conditions. This paper places emphasis on the extraction of context-information, whereas for the evaluation of ECG and blood-pressure, the most significant factor is the physical activity. The patient’s activity or movement can be acquired from the three dimensional acceleration of the body caused by each movement. Thus, an inertial micro-sensor system with a triaxial accelerometer is presented. From the acceleration signals, different methods of movement detection and classification such as Nearest Neighbor rule, K-Nearest Neighbor rule and Neuro-fuzzy classification are investigated. Using the adaptive neuro-fuzzy inference method, an online activity recognition system has been implemented and its accuracy is shown.

This paper is a progress report on the development of a communication arbiter for a mobile telemedicine system with multi communication links. Communication arbiter is a functional unit that is placed at a mobile telemedicine unit. The arbiter consists of a medical information concentrator module which is responsible for polling biosignals, and a communication manager module to manage data interchange within a mobile telemedicine system. The research is imperative in order to develop a simple, compact and low cost functional unit to be used in a mobile telemedicine system that can implement data interchange through an alternative of communication links, such as GSM, CDMA, radio, fixed phones, and internet. Basically, the concentrators is a collection of interfaces to be connected to medical devices, namely BP monitor, ECG, and FHR monitor. The function is to record vital parameters measured by the medical devices and transmit them to a laptop or PC. In the laptop / PC the biosignals will be processed and then sent out to the base unit via multi communication links. Selection of a communication link to transmit the data will be controlled by the communication manager module. Actually, this module is a modem array that can automatically determine the kind of communication links to be used. To handle this requirement, a dedicated protocol is being designed. We have just completed the development of a universal blood pressure interface as a part of the medical information concentrator. Functionally, the interface is successfully tested, and the result is encouraging. Furthermore, a communication protocol for radio and GSM communication is being evaluated in the target location. It is expected to finish the concentrator by developing ECG interface, FHR interface, and then integrate them to the communication manager module to construct the communication arbiter.

We present FP6. Integrated Project and works done by our Group on application of nonlinear dynamics for analysis of biosignals measured by new nanosensors for vigilance monitoring and for biomedical applications.

A 3D wireless power receiver is introduced for in vivo robotic capsules. It is designed to retrieve hundreds mW of power regardless of its orientation relative to the magnetic field generated from the outside of the body. Design issues such as the antenna structure and the rectification topology are discussed considering physical space limitation. Various design parameters are implemented and experimented. The selected design is implemented and tested for the power variations on the rotational positions relative to the transmitter magnetic field. The presented receiver delivers more than 300 mW regardless of its orientation.

Pulse wave is basic and, important living body signal for vital sign of measurement target or patient’s disease diagnosis. Reflection style of existent pulse wave measurement system is system that receipt light element, emitting light element hangs on palm part of finger or receipt light element, emitting light element hangs on finger lower and upper parts of permeation style. Such existent pulse wave measurement system is sensitive to motion artifact. In this study, it is going to reduce motion artifact irritableness that existent pulse wave measurement sensor has comparative rigidity degree sensor that receipt light element, emitting light element is situated on nail latitude reveal and do basic research that do example addition. This is considered to become reduction of motion artifact of other pulse wave sensor.

This paper presents a tracking method for an in vivo robotic capsule whose power is supplied from one of the multiple power transmission coils. The proposed method is aiming at selecting the best coupled one among the arrayed power transmission coils. It utilizes the fact that the driving current of the power transmitter is increased when the receiver coil inside the capsule is inductively coupled with the transmitter coil. By investigating the current increase characteristic according to its location relative to the transmission coils, we can draw the strategy on tracing the in vivo robotic capsules. This paper shows some promising results with two transmission coils and a two-dimensional power receiver. Experimental results gave the possibility of selecting the best coils by estimating the relative location of the capsule.