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A method of electronic calibration of measurement channels of multichannel analyzers of atomic emission spectra is developed for reducing nonlinearity of the dependence of the photoresponse of each channel on input radiation intensity, which is provided by obtaining measurement channel characteristics, their approximation by Chebyshev polynomials, and subsequent application of the calculated polynomial coefficients for output signal correction. A specialized unit of electronic registration and corresponding software are developed for such calibration. It is experimentally demonstrated that the measurement signal nonlinearity can be substantially reduced by using the electronic calibration. In this case, the residual nonlinearity of the photoresponse dependence on the number of photons incident onto the photodiode during the exposure time is within 1%.

Possible ways of improving laser image generators based on the circular scanning principle are analyzed. The most important sources of errors induced by the system of radial displacements and by the rotation unit are studied. Principles of decreasing the main components of instability of operation of image generators with circular scanning are described. Owing to the use of some principles, the prototype of such a generator can be put onto the second place in the worldwide rating of systems used by various companies to form structures providing high-accuracy measurements of angles (scales, limbs, rasters, etc.).

This paper describes an absolute ballistic laser gravimeter of a new generation developed at the Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences. The device is intended for use under field conditions and has small dimensions and weight. The light source in the gravimeter interferometer is an optical standard with a wavelength λ = 532 nm consisting of a traveling-wave Nd :YAG laser with intracavity frequency doubling and with a stabilization system for the saturated absorption resonances in molecular iodine. The instrumental standard error in measuring the absolute gravity by the gravimeter does not exceed ±5 · 10⁻⁸ m/s² (or 5 μGal).

The use of chalcogenide glassy semiconductors as an inorganic vacuum photoresist to obtain periodic relief structures on substrates of various compositions is investigated. It is shown that a chalcogenide resist can be successfully used in combination with interference lithography (including the immersion one) to form one- and two-dimensional submicron-size periodic structures with a spatial frequency of 300 to 8000 mm⁻¹. Technological processes of obtaining relief structures and lithographic masks with submicron sizes of elements on semiconductor, dielectric and metal substrates are developed, and their possible applications are described.

A new optical method of measuring noncircularity of cylinders is experimentally justified. The method is based on measuring the horizontal projection of velocity of a rolling circular body and calculating the maximum deviation of the local radius periodically repeated in the course of motion. Results measured by the proposed method are compared with direct measurements by a micrometer. The new method allows estimating tolerances of noncircularity in the case of defects of cylinder generatrices and the maximum variations of the radius in the case of guideline noncircularity. The noncircularity measurement error (~1 µm) is experimentally verified.

Simulation of an intelligent linear sensor for email monitoring based on theWin32 platform in the Windows XP environment is considered. The sensor emulation software of the device reads packets from a communication line, parses them, extracts email information, and sends it to a control unit. The features and limitations of the Win32 platform for designing devices of this type when using a multithreading mechanism in the emulation program are studied

A method for processing observation data based on their discretization and graphical analysis is proposed. The purpose of the processing is to determine and model the functional relationship between the inputs and output of an experimental object. The case of a series of experiments is considered.

As a result of solution of the optimization problem, a new method for estimating the amplitude-phase distribution in multielement antenna arrays is proposed and studied by numerical simulation. The method is based on calculating the principal eigenvector of the spatial correlation matrix and increases the efficiency of classical and super-resolution methods for the spatial localization of a priori unknown broadband signals.

A problem of searching for man-made objects on the basis of remote sensing of the Earth is considered. It is proposed to perform this search at the pixel level by combined processing of initial images without their preliminary segmentation; each pixel should be characterized by both spectral and spatial (with allowance for the local neighborhood) features. The efficiency of the proposed searching method is quantitatively estimated by means of processing real images.

Relations for sampling functions in nonuniform sampling of a trigonometric polynomial and its derivatives are obtained.