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Algorithms of constructing a fuzzy approximator of atmospheric temperature fields are considered. The consequent parameters of the fuzzy rule approximator are determined using the leastsquares method, and the antecedent parameters are determined by the genetic algorithm. Results of a numerical experiment are presented. Optimal approximator parameters are given

Maximum likelihood algorithms for estimating the area of stochastic images against a stochastic background in the presence of spatial noise are synthesized. A comparison is made of area estimation algorithms based on the additive and applicative models of interaction between the image and background. Asymptotic expressions for the characteristics of the area estimators are obtained. The effect of the difference between the statistical characteristics of the background and image on the accuracy of image area estimation is studied

A system of cluster analysis (unsupervised classification) for Earth remote sensing data is considered. The system is represented by three methods: the K-means method, the mode analysis of multidimensional histograms, and a hybrid method which combines the mode analysis of multidimensional histograms with their subsequent hierarchical grouping

This paper considers the operation algorithm of a hydrostatic level sensor in a liquid of unknown density which is based on the determination of the moment when the level crosses the pressure sensor and provides increased accuracy of density and level measurements compared to available methods. The algorithm was synthesized on the basis of the maximum likelihood method. The algorithm was analyzed and experimental data are given

The geometric and information parameters of the page-oriented holographic memory are optimized with allowance for the cross-talk influence on the recording density and on the bit error rate

Results of development and testing of a scanning system of interference lithography are presented. The system is designed to form diffractive microstructures consisting of microgratings with a specified orientation, a size of 5-10 μm, and a period ranging from 0.6 to 1.5 μm. The total writing field of the system is 300×300 mm. The system is used to study direct laser writing of microgratings on chromium and amorphous silicon films applied by the method of magnetron sputtering onto the glass substrate surfaces. The device and technology of direct writing of microgratings can be further used to form antireflective subwave coatings of optical elements and graphical microstructured identification marks for product protection and also to manufacture diffractive attenuators of laser radiation.

Splitting of orthogonally polarized radiation components at the exit of birefringent crystal prisms (BCPs) having a special structure and fabricated from uniaxial Iceland spar crystals is studied by the vector analysis method. For these prisms, the angle of splitting between the ordinary (o) and extraordinary (e) beams at the BCP exit depends linearly on the angle of incidence of a collimated laser beam onto the BCP entrance face. This dependence has the maximum slope only for two fixed orientations of the optical axis vectors a₁ and a₂ in both crystal wedges (BCP components). As a result of interference of polarized o- and e-waves, a straight-line interference pattern with a controlled and smoothly changed spatial frequency in the range from 0 to 125 periods/mm can be formed directly at the BCP exit. The BCP ability to form a sinusoidal interference pattern with the modulation depth not lower than 30% and with a varied spatial frequency at the aperture up to 30 mm makes it possible to use the BCP as a basis for creating a compact static Fourier spectrometer with the ultimate theoretical resolution λ/Δλ up to ~2000.

The structure and functional capabilities of a digital optical microscope-profilometer capable of operating in two modes, those of micro- and nanomeasurements, are presented. The instrument operation principle is based on measuring the phase function of the wave front of light scattered by the measured surface. Software for the microscope-profilometer and its performance characteristics are considered.

A maximum likelihood algorithm for estimating the velocity vector of a moving object from its image of unknown intensity against an applicative background whose intensity may be unknown a priori was designed and analyzed.

Algorithms for modeling images with fractal characteristics based on generalized spatial frequency filtering are proposed in which the phase or sign of the amplitude of the corresponding orthogonal transformation of the original image is retained and the modulus of the amplitude decreases exponentially for the entire generalized spectrum of the image or for the integral frequency characteristic of the spectrum. For the model images, fractal measures in a spatial region are proposed, which, similarly to the integral frequency characteristic, are invariant under multiplicative reduction in scale.