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The accuracy of estimating the shift between two discrete images of the same scene is analyzed in the situation when the shift value is under the sampling step. A new algorithm is proposed for estimating the shift. The algorithm requires a low computational complexity and its estimate errors are small. Results of computational experiments verify its advantages over the known algorithms.

A control scheme for mobile robot formation in the leader following mode is proposed. It enables to track the target and is based on using a sliding mode along the desired trajectory in the state space. Results of modeling using MATLAB/SIMULINK environment are presented. They confirm efficiency of the proposed algorithm.

Freeforms synthesized by means of perturbation functions are considered. A special feature of the freeforms based on the scalar perturbation functions and the method of their visualization is that the time of geometrical processing and the amount of data required for modeling the surface do not depend on its geometry. The freeforms based on the analytical perturbation functions have an advantage of spline representation of surfaces, that is, a high degree of smoothness, and an advantage of arbitrary form for a small number of perturbation functions.

Concepts of using new perspective systems in computer graphics are considered. The systems open up opportunities for rendering 3D visual scenes similar to the natural visual perception.

The filtering of projections in tomography algorithms, which is based on the regularization of distribution 1/z², is investigated. Numerical simulations validate that changing the filter support will substantially improve the tomograms. Comparison of the results of reconstruction by the 1/z²-filtering algorithm and the Shepp

Types of interpolation in calculating the frame-to-frame difference for decreasing the influence of the stationary background when detecting point objects are compared. The comparison is done for an observation system with a photodetector array and an oscillating axis. Methods of interpolation in the presence of a fractional shift (below the photodetector array step) are considered. Computational experiments estimating the efficiency of the methods upon detecting point objects were carried out.

The possibility of decreasing the depth of interference region in the Fizeau interferometer configuration with a semiconductor laser is considered for problems concerned with inspection of plane-parallel plates.

Numerical methods for solving 3D mixed boundary-value problems for a Helmholtz complex equation describing electromagnetic fields with the time-harmonic dependence are presented. Divergence-free barycentric finite volume approximations on tetrahedral grids are proposed. Computation of the local balance matrices and assembling of the global matrix are based on element-by-element technologies. A preconditioned semi-conjugate residual method is described for iterative solving the resulting real system of linear algebraic equations with a nonsymmetric sparse high-order matrix. Results of numerical experiments for a series of model problems on a sequence of refined grids are presented. The results demonstrate the second-order accuracy of the grid solutions and the high convergence rate of the iterative processes

A new approach to the method of iterations on subdomains without intersection is proposed. Its distinction is that the Dirichlet condition is established at the boundary at all iterations on subdomains. The convergence of the approach is numerically analyzed using an example of solving a model problem.

The finite volume method is considered for numerical solving the one-dimensional horizontal unstationary problem of drying a homogeneous layer of mowed grass in the Cartesian coordinate system. The time derivative is discretized by the parametric scheme and the nonlinear algebraic system is solved by the iterative under-relaxation method. The second-order convergence of the method is illustrated by results of numerical experiments