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Recently a great development has been carried out in control education at the Department of Automation, Technical University of Budapest. The main goal was to integrate CAD tools into the course to demonstrate the power of different control disciplines and develop the student's individual problem solving ability. The software is MATLAB and its toolboxes. The paper gives a short report on the experiences. An example from the computer problem solving laboratory is also presented. Speed control of a d.c. electrical drive is analysed by two control strategies. By use of CAD facilities there is a possibility to analyse complex problems and select the best realizable solution. The students find pleasure in these CAD laboratory exercises.

Experimental evaluations and comparisons of the passive and active biomechanical properties of isolated blood vessels from different species (dog, pig, calf, human), as well as the nature of different arterial pressure oscillations, reveal that: 1) Characteristic impedance of middle-size and large arteries changes with intraluminal mean pressure usually resulting in a U-shaped function with a minimum value around the normal physiological 100 mmHg pressure; 2) Similarly, pressure dependent adrenergic diameter responses (active strain) of different large arteries also exhibit parabolic shape with an extreme (maximum) value at 50-100 mmHg intraluminal pressure, suggesting that biomechanical characteristics of the vessel wall may define an optimum for hemodynamic operations; 3) Changes in the arterial smooth muscle tone shift the characteristic impedance curve along the pressure axis and alter the slopes of the parabola; 4) There are significant interactions between the fast 1st-order (pulsatile) and the slow 3rd-order arterial pressure wave components. These and some other characteristics of the circulatory system suggest the existence of an "extremal" forced oscillation blood pressure control mechanism in the body, optimizing the afterload of heart and the blood perfusion of systemic microvessels by minimizing the pulsatile energy expenditure at the physiological mean pressure operation level. A versatile mathematical model of this hypothetical mechanism was developed by us on an IBM PC using Pascal and 8086 Assembly languages. Simulation experiments show that such a physiological adaptive system could control arterial pressure effectively. The computer model is available on a PC disc.

Recently a great modification has been carried out in the control education at the Department of Automation, Faculty of Electrical Engineering and Informatics, Technical University of Budapest. Beyond the slight renewal and modernization of the control theory education the main goal was to develop the student's individual CAD problem solving ability. The paper shortly presents advantages and experiences of this educational illustrates the computer problem solving by an example and outlines the future developments

Recently a great modification has been carried out in the control education at the Department of Automation, Faculty of Electrical Engineering and Informatics, Technical University of Budapest. Beyond the slight renewal and modernization of the control theory education the main goal was to develop the student's individual CAD problem solving ability. The paper shortly presents advantages and experiences of this educational form, illustrates the computer problem solving by an example and outlines the future developments.

In the known models of arterial blood pressure control either pulsatile circulatory waves or very slow effects are depicted but the third-order, mostly stochastic waves are not considered. The paper deals with the result of active and passive experimental identification based upon the first- and third-order blood pressure waves measured at different arterial mean pressure levels. Relationships between parameters of pulsatile components and the slow blood pressure waves are demonstrated.

SUMMARY The changes of vibration comfort and stability of vehicles as effected by the value of frictional force generated in laminated springs are discussed and the probability of departure of the tyres from the ground is described. A partly automated analogue computer simulation being equivalent to a great number of highway experiments was applied in the study. The computer model was excited by several stochastic roadprofile - analogue signals generated by filters from the wide-band random signal of a digital noise generator.

The statistical nature of four cardiovascular signals is described by auto-correlation functions at several stabilized arterial mean pressure levels·

In biological organisms the dynamic properties of both controlled and controlling subsystems may be unknown, and often it is more complicated to identify and describe the latter dynamically than the controlled one. (In technical practice the identification consists of creating a mathematical model only for the controlled plant.) These circumstances can result in the substantial differences observed frequently in the quality of controlling versus controlled part of cardiovascular system (CVS) models.

Both physiological (wave reflection, caliber changes in resistance section, valve errors, etc.) and artificial (extracorporeal circulation, etc.) effects can lead to centripetal propagation of blood pressure pulses in large arteries. The significant changes in amplitude and shape of pressure pulses give grounds for the identification of pressure transfer along the aorta.