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In this paper, an answer to the problem of the synchronization between two non-identical Josephson junctions (NJJ) has been given. The NJJ system includes two junctions, which are modelled by the capacitive and nonlinear resistive components. The junctions have been coupled via a coupling resistance Rcp as a synchronization control parameter to each other and two distinct current sources drive the...
Left ventricular ejection time (LVET) is an important component of systolic time intervals. It has been used as a surrogate for left ventricular contractility and stroke volume. We developed a method for the assessment of LVET from wrist cuff pulse waveforms. The waveforms are obtained from a partially inflated cuff held at the level of the heart. Each test involved acquisition of 10 second sample...
The study of physiological parameters dynamic is currently the main area of research in exercise physiology. Finding dynamical models of heart rate, oxygen uptake, pulmonary ventilation and other parameters is fundamental for training methodology in sport, as well as for our knowledge of cardiorespiratory health. The present work demonstrates the application of dynamic systems models to the simulation...
Although the mechanism of electric energy flow for nonsinusoidal conditions is well described today, so fare is not yet available a generalized power theory, and theoretical calculations for the design of such devices as active filters or dynamic compensators. Therefore the task of designing compensators for optimize energy transmission with nonlinear time-varying loads in nonsinusoidal regimes is,...
Oscillators are useful electronic system that is included in almost every electronic device. There are oscillators with different type of output signal e.g. sinusoidal, square etc. In this paper the quadrature oscillator with triangular output signal and amplitude control is described. The quadrature output can be advantage for some applications. The output signal amplitude stabilization is derived...
Dynamical model of electrocardiogram and cardiovascular system are important in medicine because they can be used as approximation of the real patient. A synthetic electrocardiogram and cardiovascular signals can be generated with different sampling frequencies and different noise levels in order to establish the performance of used technique. The model implementation is based on digital and analog...
Digital oscillators are a useful electronic system that can be used for different applications. Usually the frequency and amplitude stability is important. There are oscillators with different type of output signal e.g. sinusoidal, square etc. Some of them needs floating point multiply or look-up table etc. In this paper the digital quadrature oscillator with triangular output signal and amplitude...
Oscillators are an important electronic system that is included in almost every electronic device. Usually the frequency and amplitude stability is important. There are oscillators with different type of output signal e.g. sinusoidal, square etc. In this paper the quadrature oscillator with triangular output signal and amplitude stabilization is described. The quadrature output can be relevant for...
This paper deals with dissipativity, stability, chaotic behavior and related structural properties of a relatively broad class of finite dimensional strictly causal systems. The class of nonlinear systems under consideration is described in the state-space representation form. System properties are investigated by a new approach based on a new abstract state energy concept, and on a proper generalization...
Human movement analysis is a research field with clinical and biometrics application. It has been shown useful in the objective measurement of gait, balance, falls risk assessment and mobility monitoring. Running and/or walking are also integral activities to most athletic disciplines. From a technological point of view, biometric walk-run recognition can be categorized into three approaches: machine...
Single cuff automatic blood pressure (BP) measurements are subject to errors because the BP values are based on statistical estimation rather than on physiological principles. We developed a dual cuff experimental system that uses an arm cuff and a wrist cuff. The wrist cuff function is similar to auscultation. This study concentrated on the determination of systolic, diastolic and mean BP using the...
This article describes experimental measurements of a skin temperature in vicinity of a surgical wound. Measurements were carried out in collaboration with the orthopedic department of the University Hospital Olomouc, Czech Republic. A system used for sensing, transmission and visualization of physiological parameters was developed at the University of West Bohemia in Pilsen. A main goal of measurements...
Chaos theory deals with nonlinear things those are effectively impossible to predict or control, like turbulence, weather, the stock market, our brain states, and so on. These phenomena are often described by fractal mathematics, which captures the infinite complexity of nature. Rotated systems like stars, rotating solids, electromagnetic particles etc. are very interesting because they can in some...
Frequency synthesizers are an essential part of any modern electronic system. They generate clock with desired frequency used for next signal processing. The fine frequency resolution, low spurious signals, accuracy and stability are most important for these devices. In this paper, the new principle of multiple output fractional frequency synthesizer architecture based on digital circuits is presented...
A novel chaotic oscillator with time delayed feedback is described in this paper. The oscillator is based on simple nonlinear circuit, gain stage and delay line. Chaotic systems are characterized by an extreme sensitivity to initial conditions. In this paper, instead of initial condition, the initial input wave (or voltage) is used. For chaotic system control also the gain of the amplifier is changed...
Chaos theory deals with nonlinear things that are effectively impossible to predict or control, like turbulence, weather, the stock market, our brain states, and so on. These phenomena are often described by fractal mathematics, which captures the infinite complexity of nature. Rotated spin systems like stars, rotating solids, electromagnetic particles etc. are very interesting because they can in...
Table of contents A1 Predictive and prognostic biomarker panel for targeted application of radioembolisation improving individual outcomes in hepatocellular carcinoma Jella-Andrea Abraham, Olga Golubnitschaja A2 Integrated market access approach amplifying value of “Rx-CDx” Ildar Akhmetov A3 Disaster response: an opportunity to improve global healthcare Russell J...
Pulse width modulation (PWM) is widely used in different applications. PWM transform the information in the amplitude of a bounded input signal into the pulse width output signal, without suffering from quantization noise. The frequency of the output signal is usually constant. In this paper the new PWM system with frequency changing (PWMF) is described. In PWMF the pulse width and also frequency...
This paper presents different types of electronically tunable oscillators; therefore frequency of such oscillators can be controlled by voltage or current. The square wave output and sinusoidal output oscillators are presented. All described oscillators have potential using in different application in telecommunications and measuring devices, e.g. phase locked loops, modulation and detection. The...
A pacemaker is a small electronic device implanted under the skin near the collarbone. Pacemakers monitor the heart's electrical activity. If the heart is beating too slowly or pausing too long between beats, the pacemaker will provide electrical impulses that stimulate the heart to beat. The pacemaker itself consists of a small box (the pulse generator with battery) and usually two leads that are...
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