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Specific sources of the error of forming the angle measuring structure topology by raster scanning based on the thermochemical technology of latent image writing in chromium films are analyzed. Relationship between this type of error and the specific features of dynamics of chromium film heating by laser radiation is found. A structure writing correction algorithm is proposed and implemented. The algorithm ensures an accuracy of synthesizing angle measuring structures of about several seconds of arc.

A modified signal channel of holographic memory is proposed and studied theoretically and experimentally. Compared with a conventional optical scheme, the channel enables to decrease the spread in signal of reconstructed images of information elements, which is caused by their interference in the case of a restricted Fourier hologram aperture, increase the signal-background ratio, and reduce the sensitivity to misalignment of the image and the photodetector array.

A high-resolution image is constructed by joint interpolation of a series of low-resolution images differing in mutual shifts which are not multiples of the sampling interval. Interpolation coefficients are determined by using correlations between the readings of the initial images. Results of experiments showing the efficiency of the proposed approach are given.

An optimal method of generalized estimation of the values of linear functionals is developed for the case where experimental data include not only selected values of the measured process, but also values of its derivatives of various orders. In addition, experimental data are assumed to contain a multistructural piecewise-continuous interference, which is known to accuracy of parameters and for which the instants of the structural change are unknown. The method is invariant to this type of interferences and does not require extension of the space of states, as compared to available estimation techniques.

A Welch-type estimator (an estimator obtained by averaging over the time shift) for the spectral density function of a stationary continuous-time random process is considered. The bias and variance of the statistical estimator are studied, and some recommendations concerning the choice of its parameters are formulated.

Methods for forming a three-dimensional image of the Earth surface and objects on this surface with the use of an airborne multichannel radio-thermal location station are proposed. These methods are based on range measurement, image reconstruction, and correlation-extreme combination of frames.

This paper considers a group of linear perspectives for transformation of three-dimensional visual scenes based on a patented method of displaying objects. Projective transformation matrices, including those for three-dimensional graphics application programs, are given.

A method is proposed for estimating non-multiple seasonal periods by an example of data on cyclic solar activity in the form of Wolf numbers. The values of the periods obtained are used to construct a multiplicative seasonal model in which the number of periods cannot exceed five in practice. Two possible variants of the algorithm for choosing the initial approximations of the model parameters with the use of a pseudorandom number generator are described. A modification of the two-stage steepest descent algorithm with improved performance and stability is given. For incomplete inadequate autoregressive moving average models, an additional criterion of proximity of the trajectory formed by the model to actual data is proposed, which can improve the forecast quality.

Relations between the accuracy of hotspot determination and the monitoring area of remote forest fire detection systems are considered. The indicated characteristics have a significant effect on the efficiency of the systems considered. The efficiency can be increased by simultaneously using visual monitoring means and automated mapping of forest compartments in the monitored area. Procedures for searching the forest compartment number and determining compartment boundaries are discussed.

A method for gas sampling in hypersonic hot-shot wind tunnels is proposed. A sampler designed on the basis of this method is shown to ensure heat removal for "freezing" the sample and to provide reliable information about the composition of a hypersonic gas flow. A diagnostic system for multispecies gas mixtures on the basis of small-size sensors is developed and manufactured. Testing this system in an IT-302M hypersonic hot-shot wind tunnel shows that the measurements correctly capture the trends in the behavior of oxygen concentration as a function of flow energy, but the values are underestimated approximately by 2% with respect to the true values. Possible reasons for this behavior of the sensor are discussed.