Heart rate is a parameter describing activity of human heart and its psycho-physiological character based on sympathovagal balance of autonomic nervous system, which could be instrumental for indicating stress in aircraft pilots. The assessment focuses on transition from the airplane's analog presentation of flight data to digital visualization (glass cockpit). The main objective was to examine heart rate of pilots according to the change of flight data imaging during proposed training program, using flight simulator (TRD40 type) and aircraft (DA40 type). Another aim is to interpret stress during different flight tasks and define its influence on pilots' performance. A group of ten healthy pilots with the same level of experience participated in a seven week training program. A custom designed system consisting of non-complex units was used for measuring procedures during every recorded flight. Heart rate was recorded using a commercial chest belt made by Garmin ^® . Spectral analysis of the measured signal has provided the status of sympathovagal balance based on Lomb normalized periodogram. Variation of mental stress according to the values of low to high frequency ratio LF/HF was proven according to the course of training. Results show that the transit from analog to digital visual presentation of avionic data induces stress among pilots and heart rate could be an appropriate parameter defining the actual stress condition.

From the second half of the 1990s, thanks to more affordable and more powerful technology and systems for recording based on miniaturized sensors, we can observe a more intensive development of a system that monitors the physical and psychological conditions of soldiers. Systems for measuring of physical and medical data for the diagnostics of physical and psychological state has significantly spread. This study, however, examines the current technologies and usage of the wearable monitoring systems in military. The article can serve as a guide for choosing suitable and affordable systems of quantitative evaluation of physical and psychological conditions of soldiers. In addition, the innovative telemetry monitoring system (FlexiGuard system) composed of appropriate sensors is introduced. Based on previous researches and tests, FlexiGuard system and its sensors are recommended for use in military practice.

The article presents a FlexiGuard modular biotelemetric system for real-time monitoring of special military units. The main focus of the system is on automated monitoring of special forces via parallel monitoring of each member of the special team individually, witch includes collecting sets of physiologic (or environmental) parameters. The systems consists of a set of sensors (for monitoring temperature, heart rate, acceleration, humidity etc.) and modular sensing unit, which records the measured data and sends them to the visualization unit. The measured values (i.e. heart rate, surface temperature of the body and so on) are then visualized in the graphic user interface of the visualization unit. Testing of the functionality of the system took place in both laboratory and real environment. In the case of carrying out the measurements on 34 soldiers at series of 4 probands at the same time, the sensor networks worked without any loss of signal. During the data transfer to the visualization unit, a loss of approx 0.2% of packets occurred. The system thus can offer information to the commander, which may prove essential for the optimalization of operational strategies, taking the state of wellbeing of the team members into account.

A method using body surface potential maps for assessment of myocardium lesions with changed repolarization is presented and suitable mapping system is introduced. Differences between normal and altered QRST integral maps together with torso volume conductor model were used to determine the equivalent dipole representing the lesion. Performance of the method was studied on simulated data. Changed repolarization was modeled by shortening of myocyte action potentials in regions typical for stenosis of the main coronary arteries. The equivalent dipole estimated the positions of small lesions with a mean error of 9+/-4 mm (17+/-14 mm for larger transmural lesions). The subepicardial or subendocardial character of the lesions was reflected in the dipole orientation. Tests of the method on patients after myocardial infarction that underwent coronary intervention on a single coronary vessel showed that in 7 of 8 successfully treated patients the dipole position matched well with the treated vessel. A small dipole moment in another patient indicated unsuccessful treatment. The method was implemented in a new 128-channel mapping system. Its active electrodes, battery powered measuring unit and optical computer interface help to minimize noise in ECG and guarantee patient's safety. The results suggest that the method and mapping system offer useful tools for noninvasive identification of local repolarization changes in the myocardium.