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An important initial step in seismic tomography studies that use the kinematic characteristics of elastic waves is the optimal choice of the reference velocity distribution which corresponds to the principal known component of the velocity function in linearization. A numerical analysis of the determination of the reference velocity distribution parameters depending on the properties of the system of observations used is given.

A model of the direction-finding characteristic of a moving point object for a persistent photodetector is proposed. The model ensures the calculation of the direction-finding characteristic as a function of photodetector parameters and object velocity, which form the basis for calculating the probability of detection of moving point objects. Results of numerical experiments are reported

Codes and algorithms are developed for detecting small-size dynamic thermal objects on the basis of searching for space-time anomalies in the observation field formed by a sequence of infrared images. Results of studying the method effectiveness, based on data obtained under conditions of a real background-target environment, are presented

This paper describes a new method for choosing a distribution law from a given set of experimental data that provides the best fit to a measured random variable. The method is based on a comparison of empirical distributions constructed for the original sample with the set of given laws using a continuous mapping of the distribution function onto the interval [0, 1]. As a result, the distribution for which the corresponding value of the functional is maximal is taken as the most probable distribution law for the original sample. Examples of implementing the method using statistical Monte Carlo simulation are given

The problem of computing spline approximation functions taking into account the possibility of optimizing the location of spline nodes is considered. Algorithms are developed to compute spline approximation functions with free conditions at the ends of observation intervals, with controlling of splines by the zero and first derivatives at the ends of observation intervals, and with the provision of optimal locations of spline nodes. The results of mathematical modeling of the algorithms for computing spline approximation functions are presented

The influence of various methods of obtaining surface images on the calculated value of their fractal dimension as a quantitative characteristic of the surface state is studied. It is demonstrated that images obtained both by a scanning electron microscope and by a photocamera are characterized by a noticeable noise level, which alters the behavior of the fractal dimension. Various methods of correction of the observed effect are discussed

The exchange rate formation process is represented as the sum of a low-frequency deterministic trend and a high-frequency stationary random component for which the covariance function, the spectral density, and the increment correlation function are obtained. Theoretical results are in good agreement with the results of processing of observed data. The model explains the occurrence of Elliott waves on exchange rate paths and generates a parametric family of random processes with spectral characteristics ranging from white noise to a first-order autoregression process

A method for determining the optimal internal parameters of technical systems, based on the analytical description of the operational capability range, which is defined as a set of linear constraints, is considered. An expression for the objective function, which allows one to use any known search method for optimizing the system by the criterion of the operational capability reserve, is derived

By solving coupled-mode equations in laser Doppler tomography, expressions for output signals are found, which describe light diffraction on a volume grating with a mutual (in the general case) shift of the amplitude and phase components. Signal parameters that are least prone to the influence of uncontrolled characteristics of the optical system and studied medium are found. The phase shift between the signals of a two-channel heterodyne detector of scattered light is obtained as a function of the character of the amplitude-phase components of the test grating

An experimental model of a test rig for formation of images in a computer and insertion of these images into the optical-electron path of an infrared imaging system is considered. Experiments on synthesizing images in the range of 3–5 µm and dynamic scenes are performed. Experimental estimates of the model test rig are given