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The paper presents the experience in testing virtual colonoscopy on examining patients with colonic diseases. The potentialities of virtual colonoscopy in imaging tumors, polyps, diverticula, and strictures of the colon are assessed. The place of the procedure in the algorithms of examination of patients is defined. Its advantages and disadvantages are preliminarily estimated.

Described in the paper is a reconstruction algorithm for special distributions of optical parameters of biological objects based on the non-stationary axial model of radiation transport in case of proportionality of the absorption and scattering coefficients. The proportionality coefficient, used in reconstruction, is shown to influence a precision of images being restored. The appropriate recommendations are defined of how to diminish the occurring distortions.

Comparative assessments of the efficiency and noise immunity of the algorithms detecting the shock cardiac rhythms (SCR) are described in the paper. It is suggested to use the rejection filter of ventricular fibrillation as the principle algorithm for the SCR detection in an automated external defibrillator. The use of the method combining the after-threshold interval and the method of spectral analysis is demonstrated to be preferable for a portable external defibrillator.

Described in the paper is a method of data deconvolution of ultrasound scanning (solution of the deconvolution equation in the linear metric) that ensures a higher precision of images being restored versus the traditional Wiener filtering. Simplex algorithm with an originally modified efficiency function was used to solve the task. The results of experiments testifying to the efficiency of algorithms in the ultrasound image processing of the mammary gland of a patient are presented.

The paper deals with the optimization of a hemodialyzing procedure. An algorithm is proposed to set and control the profile of ultrafiltration in each specific moment of the hemodialyzing procedure, i.e. to control the basic parameters of the procedure as a hemodialysis time function.

The paper reviews the existing methods for identifying QRS complexes. An attempt is made to make a well-defined classification of available algorithms in an approach to QRS detection. Emphasis is laid on the consideration of specific requirements for such algorithms by computer-aided real-time ECG systems. A task of choice of the most suitable method is formulated. An algorithm based on the well-known principles of frequency-time detection is proposed as an alternative solution of this task. The algorithm makes it possible to single out QRS complexes from real-time ECG and to effectively make a digital signal processing by available optimized libraries. The method initially used in the Matlab package has been integrated within the laboratory computerized ECG system.

The paper deals with the synthesis of algorithms for non-linear control of the degree of contrast of digital chest images by bringing the baseline histogram of brightness to the prearranged form and with practical analysis of the efficiency of the algorithms derived.

The paper shows how to improve the quality of diagnosing coronary heart disease (CHD). It proposes a mathematical model of coronary circulatory disorders, which is based on the definition of CHD as a cardiac abnormality caused by the imbalance of coronary blood flow and myocardial oxygen consumption, outlines an algorithm for construction of this model. With this model, a computer system has been designed for examining a patients with CHD, which permits the construction of a virtual model of coronary circulatory disorders.

The paper considers principles in the design of measuring impedance converters which can find medical and biological applications. The converters are noted for a wide range of amplitudes and frequencies of measuring currents with better metrological characteristics.

Despite the fact that the duration of cardiac cycle complexes is a main diagnostic index in interpretation of ECG, a unified common approach to constructing measuring algorithms is lacking now. The paper reviews the methods of detection and measurement of the onset and termination of cardiographic complexes. Their link with the general theory of assessment by using the Fischer mathematical statistic methods, the Winner filtration methods, the approximation methods by spline functions and Kalman's filters is considered. An attempt was made to describe the pattern of cardiac cycle pulses on the basis of physiological processes of cardiac electric activity.

The paper proposes a mathematical model of development of a cell population with a changing proliferative activity. The model is based on the Markov branching process with cells of several types. A procedure for identifying the constructed model by experimental evidence is being developed. An example of model construction and assessment for cultured diploid fibroblasts is given.

The paper defines requirements for reference signals to check measuring the algorithms of automatic electrocardiographic systems. It proposes a reference signal which meets these requirements and gives a block diagram of a test bed.

The paper deals with the automatic processing of a Doppler ultrasonic signal and with the development of the respective software. It outlines the theory of Doppler gram synthesis and the recognition algorithms for typical elements, which are based on the developed theory, for averaged summary blood flow and spectral image of the signal.

The paper outlines the applicability of the sample recognition theory to process the data obtained with the use of multifiber optical catheters as part of information systems for diagnostics and visualization for microsurgery. A specific example of synthesizing the image assessment algorithm by employing the sample recognition theory is considered for the visualization system for a laser angioplastic unit.

This paper presents the method, algorithm and results of structural identification as a model of pilot's perception of perturbed angular motion of the cockpit and its transmission to the joystick as well as spectral density of the remnant corresponding to the transmission process. Assessments of scalar quasilinear and (more effective) multichannel models of pilot's functions are given. The assessments have been obtained for a single operator. They illustrate the potentials of this procedure.

The paper is concerned with a program for data processing of dynamic scintigraphy of the skeleton and skeletal muscles using 99mTc-sodium 1-hydroxy-ethane-1, 1-diphosphonate. Employing gamma-chamber computer the program enables rapid and precise computation of the coefficient of RP elimination from the blood and the coefficients of RP accumulation by the bones and muscle tissue. Based on those coefficients one can make diagnosis and follow the time-course of pathological changes occurring in the skeleton during endocrine diseases.

The paper is devoted to the theoretical substantiation and approaches to the determination of the main parameters of circulation of the internal organs on the basis of the results of indirect radionuclide angiography. Formulas for the calculation of circulation mean time, blood flow volumetric rate and its fraction of the cardiac output were given. Using algorithms, cited in the paper, one could prepare programs for the processing of radionuclide angiography data on computers.