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The efficiency of a number of the classical methods of supervised classification of hyperspectral data is estimated by an example of discriminating the types of the underlying surface in natural and man-made areas. The minimum distance, support vector machine, Mahalanobis, and maximum likelihood methods are considered. Particular attention is paid to studying the dependence of the data classification accuracy on the number of spectral features and the way of choosing them in the above-mentioned methods. Experimental results obtained by processing real hyperspectral images of landscapes of various types are reported.

A model of image recording in the circular microscanning regime is considered. An algorithm that allows obtaining an image with a large number of samples from a set of smaller-size frames for a known path of the scanning array is proposed. Numerical simulations are performed to estimate the changes in the amplitude of a small-size object with a static position of the photodetector array and microscanning in the start/stop mode. The influence of the gap between the array elements and scanning radius on the object amplitude is studied. The final ratio of the object amplitude to the random noise level in the case of static accumulation and circular microscanning in the start/stop mode are compared for arrays with different sizes of the gap between the array elements.

This papers describes the effectiveness of textural features on the basis of gradient tensors in the problem of segmentation of images containing textures with structural redundancy. It is shown that the use of the bank of Gaussian bandpass filters in the formation of a feature space which is invariant to shifts and rotations of textures improves the performance of the segmentation algorithm. Examples demonstrating the application of textural features to the problem of segmentation with an unknown number of texture classes contained in the image are presented.

A new goodness-of-fit test constructed with the use of the interval estimation of the probability distribution function is proposed. A comparative analysis of this test with the Kolmogorov test is carried out. It is shown that it is possible to select the correct distribution function and the hypothetical function different from it so that the proposed goodness-of-fit test can have a significantly better performance than the Kolmogorov test. The presented numerical simulation results are in good agreement with the theoretical conclusions.

With regard to the problems of passive ranging, one of the modifications of the wellknown energy method for determining the range to an emitting target with partially known motion parameters on the basis of a single receiving point is developed. The problem is solved using solely the measurements of the power (amplitude) of the received signal on a predetermined time grid with no account for direction-finding data. The analytical dependences allowing for exploration of the working region of the method are obtained. An algorithm for the formation of the resulting ranging estimate in the current time taking into consideration the measurement redundancy is constructed. The results of computational experiments that confirm the possibility of practical implementation of the proposed modifications of the energy method are presented. The recommendations on the use of the results obtained in multipoint systems of passive location are given.

A problem of tracking of a group of identical objects with a variable shape and a large number of occlusions is considered. This problem is important for biology and safety systems. An algorithm of detection and tracking of biological objects on the basis of a sequence of depth images is proposed. Being tested, the algorithm provides one mistake per 193 collisions for the worst sequence.

The problem of face recognition is discussed. For this purpose, a method based on scalar perturbation functions and a set-theoretic operation of subtraction is proposed. It is shown that all surface points and the mask volume are used in the process of sample testing for more accurate identification.

Migration processes, as well as birth and death rate determine the population dynamics. The main type of migration for rodents is dispersal which has not been studied thoroughly. The typical and maximum distances of species dispersal and permeability of some landscape elements are yet to be found out. The aim of this study was to investigate the dispersal of two most abundant rodent species using a specifically modified method of non-selective marking. It was found out that dispersal distance of a pygmy wood mouse ( Sylvaemus uralensis Pallas, 1811) is larger than that of a bank vole ( Clethrionomys glareolus Schreber, 1780). The determined dispersal distance of the bank vole (up to 2 km) proved the longest for this species. Dispersal process and spatial structure of rodent populations were greatly affected by the territory characteristics. Barrier landscape elements that impede the dispersal, can increase the animals’ local density. The “migrant trap” effect was described for the first time.

The paper deals with the nature of mathematical concepts, genesis of natural numbers and the temporal structure of consciousness. We analyze the arithmetic model of time and propose a new geometrical model of bundle time which is based on the hypothesis of independent time dimensions corresponding to external linear time and internal cyclic one.

Thermodynamic characteristics are calculated for aqueous diamine solutions prepared by substituting an amino group for the hydroxyl group of amino alcohols. Patterns are revealed in the change of the structural properties of the mixtures. The correlation between the entropy and enthalpy characteristics of the water-diamine systems and the excess packing coefficients suggests that the universal interactions determine the structural and energy properties of aqueous solutions of the studied diamines. The form of the concentration dependences of the structural and thermodynamic characteristics in the studied systems is found to be symbatic with the data for the mixtures of water with aprotic amides. The reasons for this are discussed by comparing the results with our previously published data for aqueous solutions of aprotic amides.