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The article is devoted to the construction of a mathematical model and the algorithm for reducing a set of staganalytical correlated methods taking into account the computational complexity of the problem. The basic steganographic methods for the images spatial domain are described. Known steganalytical algorithms for the spatial domain are reviewed. It is shown that a significant number of steganalytical...
The method principal component (PCA) allows to allocate from a matrix of these several objects with a large amount of signs only 1–3 vectors containing 90–95% of information. Usually measuring problem of assessment of these main components is solved by the iterative NIPALS procedure or the algebraic SVD procedure, however both of these methods often give ambiguous estimates. For the purpose of elimination...
The possibilities of implementation of Markov model of radio signals with various types of modulation at the output of the radio transmitter are considered. Markov models of Gaussian random processes are studied. The properties of the obtained models are analyzed. For their graphic description, three-dimensional representations of matrices of joint and transition probabilities are proposed. The properties...
The problems of constructing Gaussian signals models with a given three-dimensional probability density on the basis of the biconnected Markov chain are considered. The article presents a Markov model shaping technique; to describe it, the use of three-dimensional diagrams for joint and transition probabilities matrices as well as their contour lines is proposed. The properties of the biconnected...
The authors gave reasons for preference of choice of hardware and software making possible to perform automatically the low-temperature research of electronic components (analog ICs, BiTs, JFets). The article considers measurement techniques, software features and an experimental setup that allow determining the main parameters of analog integrated circuits (IC), bipolar transistors (BiT) and junction...
At present, there are no devices for operational control of valuable components in the gold-mining industry. The proposed device for the automatic control of gold concentration measurement is based on the anion-selective electrode analysis method which has several advantages: rapidity, compactness and ability to be easily integrated into an automated process control system. The ion-selective electrode-sensor...
The paper deals with the structural synthesis of a tracking mechatronic converter on the basis of up-to-date element base. The urgency of the research is substantiated by the analytical review of modern information technologies for controlling the mechatronic systems and converters. The electromechanical subsystem of the mechatronic system contains a contactless permanent-magnet machine as an energy...
The effective solution of operation problems, adjustment and dispatching management of thermal networks can be obtained applying modern mathematical modeling methods, calculation and optimization. However, lack of reliable information about their actual parameters and characteristics substantially depreciates virtually all sets of these methods. The majority of thermal networks parameters and characteristics...
The article is based on the use of the concept of discrete iterative Verhulst-Pearl transformation. First, the non-standard application of this mapping in the financial sphere is shown. Then in the work a two-dimensional model of antagonistic and dependent two sets was studied. The number of each of them depends on the opposite. With the help of computer programs, new graphical schemes of these processes...
We conducted a comprehensive study using the spectrophotometric complex “Cary 5000” with the accessories “DRA” and “UMA”. We used this complex to obtain accurate, high-precision results for different material types, especially for single crystal optical materials in the range of the wave-length from 250 to 3500 nm in polarized light with different types of polarization and non-polarized light, in...
The aim of this paper is to develop the theoretical basis of mechatronic systems construction using the principal components projection method for conducting natural model measurements of mechatronic systems parameters. It is difficult to name a technical sphere where mechatronic systems aren't applied. They can be found in many household appliances, communication devices, they make an integral part...
The planar interdigitated electrode system used in a electrochemical cell for impedance measurement is considered. To estimate the influence of microelectrode parameters on the impedance of the electrochemical cell, the analytical approach is proposed. This approach includes analytical modeling for determining the potential distribution in the interdigitated microelectrode system and the usage of...
The article deals with a robust photogrammetric method to measure the geometric parameters of large scale objects with axial symmetry. The method is based on measuring the 3D-coordinates of the centers of circular retroreflective targets placed on the object in planes perpendicular to the axis of symmetry with the minimum moment of inertia. There has been developed a two-stage outlier filtering algorithm...
The authors highlight that stationary condition monitoring systems for high-voltage equipment is an essential prerequisite of the Smart-Grid implementation in the industrial electric networks. Diagnostic systems commissioning is relevant for network and electric furnace transformers of iron and steel works. The system operation performance is deteriorated because of lack of the methods intended for...
A modified measurement procedure for the purity determination of high purity potassium iodate is described. The procedure consists of the coulometric standardization of sodium thiosulfate by generated iodine, stoichiometric interaction of standardized sodium thiosulfate with potassium iodate and the coulometric titration of excess sodium thiosulfate by generated iodine. In the proposed measurement...
The article reviews the capabilities and particularities of the approach to the improvement of metrological characteristics of fiber-optic pressure sensors (FOPS) based on estimation of the nonlinearity value of the membrane stress-strain behavior and the adaptive method. It is shown that this method applied to the metrological characteristics allows for the measurement errors to be minimized. It...
The problem of the technical diagnostics of measuring channels under the conditions of information introduction and measurement systems in terms of complex safety is considered. The purpose of the study is to build models for creation and evaluation of the effectiveness of the systems that ensure the safety of the technical diagnostics of measuring channels based on a systematic approach to the accounting...
This paper considers a method for detecting faulty elements in a linear phased array by means of set near-field probes. Using the asymptotic correspondence for two- and three-dimensional problems of the antenna theory leads to simpler mathematical models for the vertical dipoles array. A numerical study of mathematical models is based on the iterative regularization of the ill-posed problem of reconstructing...
The paper offers mathematical models and software for electromagnetic calculations in conducting plate with flaws (cuts). It solves the problem of the influence of one or more straight line intersecting in one point of flaws on eddy currents and electromotive force (EF) induced in a coil with current. The coil is located above the nonmagnetic infinite plate orthogonally to the lines of flaws. Under...
The article considers a possibility to apply a method for the estimation of electric losses in the transformer based on the control of temperature on its surface without a current measurement in windings. For the accounts the differential equation of a heat account of the transformer is used. The complexity of its direct application in view of the necessity to use the physical sizes depending on the...
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