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Modelling ofbloodflowinvesselsoffersauseful toolfor vascular systemexamination. Propagationof bloodpressure and blood flow pulses are analyzed in the present paper. The pulses shapes are significantly influenced by their reflections at vessels inhomogeneities. The whole body arterial model is used for different phenomena investigation. Influence of waves' reflections on their profiles is examined. Consequences of vessels bifurcations, stenosis and sclerosis are simulated and the simulated results are compared with experimental data taken by means of PPG.

Thepaper proposes utilizationof eddy current inspection fordetection ofdefects intheartificialheart valve. Artificial heart valves are prosthetic replacements which are used if the function of the natural heart valve is limited. A special type of prosthetic heart valve replacements is the Bj¨ ork Shiley convexo-concave (BSCC) heart valve. The fractures of the BSCC artificial heart valve usually affect the outlet strut. If the fracture of the strut is not detected in time the patient can die of heart attack. Detection of the fracture in the outlet strut is the concern here. Experimental measurements are performed in order to evaluate the detection capability of the technique and the sensitivity of response signal to dimensional parameters of a fracture. A BSCC heart valve prototype having the electromagnetic characteristics of the Co-Cr (Hayness 25) alloy is inspected with a probe. A non-conductive defect is positioned in the outlet strut and its dimensions are varied. The probe is positioned above the centre of the crack and the frequency of exciting signal is changed in a wide range. The presented results demonstrate that the sweep frequency technique can enhance eddy current inspection of a defect in BSCC heart valve.

The paper deals with modelling and simulation of a human brain arterial system using analogous electromagnetic systems, especially propagation characteristics of electric transmission lines. Cascade connection of analogous equivalent transmission line elements represents a vessel tree concerning both the electromagnetic parameters and the topology. Elec- tromechanical analogy between physiological and electromagnetic values enables a description and following simulation of a cerebral haemodynamics by means of electric circuits analogous relations. The vascular dynamics modelling and simulation represents an important tool for the non-invasive computer-aided investigation of the brain arteries pathological deformations. The presented simulation results give the information about the blood dynamic characteristics also in the case of cerebral arterial stenoses or aneurysms under various stenosis degrees. The obtained results can provide helpful knowledge for the practical treatment of the basic brain arteries.

The present paper deals with the utilization of the electromagnetic-acoustic transducer (EMAT) for the non-destructive testing of conducting materials. The principle of the EMAT consists in the interaction of the electrodynamic structure of materials with an external electromagnetic (EM) field under influence of a bias magnetic field. It offers the possibility to generate an acoustic mode of the penetrating EM wave with the slow velocity and the attenuation of the acoustic wave or on the other hand to detect the EM wave due to its radiation from the surface of a conducting sample. The main advantage of the EMAT is the contactless generation and detection of the acoustic wave, or the acoustic mode of EM wave in a wide range of frequencies and temperatures. The special properties of EMAT’s driving and detecting devices are presented in the paper.