SCIENCE & EDUCATION

In this paper the authors describe a laser method of detecting oil pollution on rough sea surface by means of angle scanning. It was shown that the laser method allows to detect oil pollutions in a broad band on sea surface with high probability of correct detection and low probability of false alarm.

In this paper numerical calculation of values of light negative air ion (LNAI) stream was carried out for a cylindrical geometrical model in the COMSOL Multiphysics 4.0. on the basis of the solution of the Fick equation. The relative error of a light negative air ion stream appearing with simplification of geometrical model of the upper respiratory tracts from a tore segment to the cylinder didn't exceed 5,3 %. Possibility of use of a cylindrical model of the upper respiratory tracts was proved by means of experimental studies of streams of the light negative air ions (LNAI) settling on walls of the upper respiratory tracts of an average person.

The authors describe the problem of recovery of gas concentration in laser photo-acoustic analysis. Signal processing procedures based on projective method are described for the differential absorption method. Usage of the projective method was proved to be efficient for solving the problem of recovery of gas concentration for multi-component gas mixtures.

 For solving classification problems of air and ground targets the authors justify informative signal features and robust neural network algorithms of formation of decision-making areas; these algorithms use prior information on initial statistical characteristics of acoustic signals.

This paper covers selection of resolution tools (test-objects) for visible digital optic-electronic systems. The measurement accuracy of physical quantity depends on the measuring tool type, in other words precision of measurements to the true value of the measured quantity. The given task is solved by a physical experiment method. The experiment was conducted in laboratory and flight conditions. The experiment results were statistically analyzed.

 The authors consider a laser fluorescence method of detection of plants state under stress. It is shown that the laser fluorescence method is an advanced method for remote detection of plants stress states, and it requires further research and development.

The authors consider a question of metrological assurance of a measuring system model on the basis of fiber-optical Bragg gratings. The article describes of stand construction schemes for research of spectral characteristics of signals formed with fiber-optical Brag sensors and also for research of a group delay. The authors analyzed design parameters influencing metrological characteristics of the model. The results of the experimental researches of metrological characteristics with use of the developed stands are presented.

 The article considers algorithms of detection and recognition of random non-centered signals and disturbances in remote strobes of pulse locators. Neural network and regression algorithms were proposed for formation of decision-making areas. For single deterministic signals quasi-optimal filtering was considered.

 The article describes the possibility of obtaining waveform envelope readings of input implementations using the Hilbert conjugated process which can be used as informative parameters of the signals that are invariant to the energy spectrum medium frequency with a relative width of the band to 0.7-0.8. In this case automatic tracking of the sample rate is performed according to the changing medium frequency of the input implementation energy spectrum.

The article considers quality assessment criteria for recording/reading process of magnetic signalograms with correct information read-out. The authors analyzed the distortions arising during magnetic signalogram visualization. The article describes boundary conditions allowing to determine boundary values of spatial periods of recorded magnetic signalograms to which undistorted information corresponds. Recommendations on selection of double-layer magnetic materials parameters are given. The degree of the optical efficiency for reading process, image contrast and range of the reproducing of spatial periods is determined with the usage of these parameters.

The installation of frame type for the purpose of balancing of floated sensitive element (ESE) of gyro-instruments in fluid, besides the frame, includes an electromagnetic suspension (EMS), an angle data transmitter (ADT), a torque sensor (TS) and two columns firmly attached to the foundation of frame.  Armature of ADT, TS and two aligning elements (AE) of EMS were fixedly attached to two semi-axis of the frame, and their stators were attached to the apertures of the columns. AE of EMS are used both for suspension of the frame in fluid (without ESE, and then together with ESE) and as force sensors (accelerometers) allowing to determine the values of forces applied to the armatures of AE of EMS. Residual weight of Δ G or floatability of Δ P and trim moment of Md of ESE were determined with the results of measurement. The feedback “angle data transmitter – torque sensor” was used to determine the moment of static unbalance Mst about suspension axis of ESE.

The radio telescope inertial orientation system is based on using the method of autonomous azimuthal orientation by means of currents measured in horizontal correction channels with the azimuthal rotation of the gyroplatform. The authors studied observability conditions of azimuthal orientation error and instrumental errors of a three-axis gyrostabilizer with constant and variable command precession around vertical axis.

 In this paper the authors consider a laser reflectometric method of measurement of thickness of metallic films on dielectric substratewas. Optimal wavelengths for measuring thickness of gold nanofilms on quartz substrate were determined; error estimation for determining film thickness from laser reflectometry measurements was obtained. Mathematical simulation shows that the method allows to measure a gold nanofilm with thickness from 1 nm to 5 nm using wavelength 1310 or 1550 nm with mean error ~ 0,15 % and with thickness from 5 nm to 50 nm using wavelength 515 nm with mean error ~ 0,25 % and the relative root-mean-square value of measurement noise 1 %.

Laser monitoring problem of oil pollution at earth's surfaces was considered in this paper. It was shown that use of laser method based on detection of fluorescence radiation within four narrow spectral bands and hierarchical method of classification, allowed to classify oil pollution at earth's surfaces with a probability of correct classification close to one.

Some issues relating to the simulation of shock pulse excitations were considered. Common schemes of shock equipment were presented as well as the method of calculating of the parameters of elastic and elastic-plastic contact zone of colliding bodies. It was shown that the conditions of simulation testing could be more severe in the sense of strength than the real object performance conditions depending on the dynamic factor value (shock spectrum).

The methodology of selecting of classifiers’ features was described in this article; these classifiers were used in processing of diffraction image of complex spatial objects. The substantiation of the separation of the object class into subclasses in terms of information theory, as well as reasonable selection of object classes with the usage of ellipsoidal estimation were given. The criteria of qualitative selection of classifier’s feature vector, answering questions about the size of teaching selection, the cardinality of the set of classes, the essential dimension of feature vector, were developed. Evidence-based approach to the selection of informative features of classifier of signals, based on the concept of entropy of information theory and ellipsoidal estimation, were proposed.

 The authors consider a simplified linear model of aircraft pitch movement for real-time prediction to support control design. The model is derived out of the full nonlinear system of aircraft space movement. The model parameters estimates are achieved through the least square regression estimator using moving interval. Some examples of flight test data processing are also presented.

The authors consider application of a chemical-mechanical polishing method for planarization substrate surfaces in nano -and microsystems technology. The authors propose a method to calculate distribution of magnitude of wear on operating surface which undergoes chemical-mechanical polishing. The authors provide results of calculating distribution of magnitude of wear on the operating surface for some modes of processing wafers. The results can be used for design of chemical and mechanical polishing of substrate surface in nano- and microsystems technology.

A fuzzy-model for quantitative estimation of the generalized indicator of the chemical current source technical state, built in multifactorial space of fuzzy variables, was the source of new information in the form of partial derivatives for gradient computation at any time interval. It became the foundation of creating a method for forecasting the residual resource of similar technical objects. This method allows controlling technical state of working object, increasing validity and efficiency of making the decision about whether or not to extent the term of exploitation. The developed method is multipurpose and can be easily adapted to any particular object.

 The authors consider numerical solution algorythms for identification and concentrations calculation of substances in the atmosphere. Instead of solving the multidimensional system of linear equations it is proposed to solve one or several one-dimensional systems. Conversion to one-dimensional problem is performed by correlation analysis. The influence of noise in the initial spectrum on errors of inverse problem solution was studied.