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Measurement of fingers and hand kinematics during the grasping activities and manipulation with various objects play an essential role in ergonomics, sport science, occupational medicine, and rehabilitation, as it is an indicator of hand function. That is why the design and realization of a device for finger flexion and extension and forearm motion became the main objective of this article. The work deals with designing and implementing the system prototype, its calibration, and testing under laboratory conditions. The designed device is promising to be used in occupational medicine and rehabilitation applications such as the device to assess the hand function impairment and track patient hand function disability recovery progress.

Heart rate variability (HRV) reflects the physical health and ability of the organism to handle stress situations. HRV biofeedback is a real-time training process which helps reduce stress and asthma severity. The most important prerequisite for the HRV biofeedback is the detection of R peaks in the ECG signal. This article describes in detail a real-time algorithm capable of R peaks detection. The algorithm is implemented within a standalone C# application and functionality thereof is demonstrated. The results indicate that the proposed algorithm is immune against various types of artefacts.

The objective of this study was to explore the possibility of combining the theoretical human arterial model based on electromechanical analogy with real impedance cardiography measurements - the fusion of which would create a per-person adaptable model. Cardiac activity was modeled based on two different sources – the first model (Model No.1) included real-life hemodynamic parameters based on variation of universal aortic pressure, while the second model (Model No.2) was based on real-life aortic flow derived from measurements. Simulated blood pressure propagation in proximal aortic segment was compared with reference pressure values measured by an electronic sphygmomanometer. Model No. 2 was found to be more accurate and better representative of real behavior of the arterial system under normal conditions. Additionally, the blood pressure and blood flow curves directly reflected the variability of the cardiac activity.

Human arterial system simulation models represents a helpful tool for investigating blood pressure and blood flow propagating from the aorta towards upper and lower peripheral vessels. Real-life hemodynamic parameters are used as input for the arterial model based on electromechanical analogy. The mentioned parameters are determined from impedance cardiography measurements carried out on five human subjects. The theoretical model is thus individually adapted using real-life hemodynamic parameter values and the impact of stroke volume and heart rate changes on blood pressure and blood flow waveforms are investigated. We can conclude that the stroke volume influences especially the amplitude of the said curves, whereas the heart rate modifies shape thereof.

Impedance measurements are gaining importance in wide field of research. This paper presents the design and construction of an impedance measurement device based on the AD5933 integrated circuit. Our low-cost system can be used in many areas of bioresearch. For the purpose of this paper, the device was used as impedance cardiography (ICG) analyzer for human thoracic impedance measurements. The measured raw data from impedance recordings were processed in order to extract specific features and several important hemodynamic parameters were calculated from the ICG curve.

Within this work, the analysis of the selected arterial system segments were performed regarding to various hematocrit values. Properties of arteries were transformed to electrical quantities by using electromechanical analogy. There is theory of two port electrical circuits, which was used for analysis of the selected arterial segments. The characteristic voltage and current transfers were calculated in order determine the atrial properties as function of frequency for the various hematocrit values. The work deals with model of blood viscosity assuming non — Newtonian flow and then combines it with Newtonian blood flow, which is characteristic for the used arterial system model. The impact of different hematocrit values on the selected arterial segments is evaluated.

The cardiovascular disease is a serious problem in the world. The early diagnosis of heart disease leads to minimization of deaths. The analysis of electrocardiogram (ECG) patterns and cardiac frequency is used for detecting arrhythmias and discovering the nature of disease.. In many cases patients encounter heart problems (pain, sudden change of heart beat) but no longer have an ECG device and/or equipment for measurement. These drawbacks can be overcome using an ECG logger. In this paper it is described hardware design of one-lead ECG data logger. The designed ECG logger is small and compact device without any cables - it is a miniature, hand-held device with fixed electrodes for fingers. Measured data are stored on built-in microSD memory card and then transferred to PC via USB connection.

This work combines photoplethysmographic and electrical impedance plethysmographic measurements. A lack of blood delivery and oxygenation during pregnancy may have fatal consequences for the fetus. Photoplethysmographic measurements illuminate the tissue and measure the change of light absorption. In this contribution a photoplethysmographic measurement system is presented. The hardware concept includes an analog signal processing circuit for the photodiode and a special driver circuit to power two light sources (red and infrared LED). For photoplethysmographic measurements only one LED is required, but in view of future purposes, such as pulse oximetry, a second LED is already implemented. Furthermore this paper shows results of electrical impedance plethysmography. This designed photoplethysmographic measuring in combination with impedance cardiography might be promising in examine of fetus. Keywords-biosensors; impedance cardiography; photodiode; photo plethysmography; oximetry

Recently, EEG-based technology has become more popular in intuitive, user-friendly web content designs and developments for serious games. There is a need for some feedback or measure as to whether a specific serious game can enhance the selected knowledge or identify critical parts of the websites. For this purpose, a software application was designed and implemented, allowing the EEG spectral analysis, location of event flags, and interconnection between EEG and video recording of the performed task. The software works with our in-house measurement infrastructure prototype, which is used to simultaneously measure and record EEG and video signals online.