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The paper deals with the creation of a universal metrological complex meant for the calibration of various photometric and radiometric equipment as well as distant and collimated optical radiation sources within the range of 0.25–1.25 micron. The main lines of the research are the extension of the range of registerable radiation intensities, primarily in the area of weak radiations, automation of...
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...
The paper demonstrates the possibility of the Newton-Kantorovich method application to numerically solve the Volterra polynomial integral equations of the first kind. The specific features of the studied nonlinear equations make it possible to specify an initial approximation for the iteration process represented by solving the respective Volterra linear equations of the first kind. The method convergence...
Oxyhydrate colloid gel parameters measurements and estimations are performed in this paper. Measured parameters are sizes of oxyhydrate clusters, concentrations, polarization vector values and some others. Measurements were performed with simple methods as measuring optical density, electric current value and microscopic observation. Accuracy of these observations is typical for these well-known methods...
This paper proposes a new effective algorithmic basis for solving the problem of choosing the permissible deviations of the parameters of the elements, choosing the measured currents and diagnostics of the electrical device elements. The algorithms developed by the authors are based on the new modification of the Gaussian elimination method to solve the systems of linear algebraic equations. One of...
A five-stage Field-Noyes-Köros model of the Belousov-Zhabotinsky reaction and the corresponding mathematical model of the oregonator is presented. A system of equations for the oregonator steady states is derived. The oregonator steady states are calculated for different values of the stoichiometric coefficient. The steady state was investigated according to the experimental data of the model's authors...
The article considers the algorithm of estimation of systematic measurements of aircraft air parameters in flight, based on the application of methods of the theory of identification of dynamic systems. The main complexity of the problem under consideration is caused by the dependence of airspeed, angles of attack and slide on wind speed, since these signals, that is, airspeed, angles of attack and...
In this article the authors analyze the relevance of intelligent sensors use. The review and classification of the functions of intelligent sensors and systems is given. Structural diagrams for an intelligent measuring system of magnetostrictive linear displacement sensors are considered. There are two ways to implement the self-calibration function, with mathematical control points and active control...
The article is devoted to the problem of instability of a liquid film flowing over a solid surface under the gravity action. The mathematical model of the condition of the free surface taking into account the heterogeneity of surface tension and shear stress is presented. The results of computational experiments on the wave characteristics of liquid film and areas of instability under the influence...
The paper aims at improving the accuracy of the calibration of strapdown inertial navigation systems (SINS). The calibration is carried out using a 2-axial motion simulator. A new computational method is investigated for the calibration coefficients of the error models of accelerometers and gyroscopes of the strapdown inertial navigation system based on the errors of the system output signals. The...
This paper is dedicated to one of the promising directions in the development of aircraft air data systems that provide information about the altitude and airspeed parameters. The issues of the required air data measurement error as well as of further conversion of the measured air pressure by the pressure sensors are considered. In connection with the trend of eliminating of movable vane aerodynamic...
The accuracy and productivity of measurement performed with the help of coordinate measuring machines depend not only on their technical characteristics but also on the strategy used to select the number, location of the points and the sequence of their circumvention on the surface. The article proposes a new strategy for the determination of the number and location of control points on surfaces based...
The article considers an unconventional way of analog-to-digital conversion (ADC) of current signals conveyed by the sensors based on the application of the properties of the linear analog current adder (ACA). The authors give the main equations, the ACA circuitry as well as the results of its computer simulation which show that the k-valued code is output current signals of the ADC of the considered...
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 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...
This paper proposes an estimation method for the latent variable Rasch model based on the method of least squares which allows a continuous data set using. The research suggests the application of original approaches within the method for the solution of some applied problems. The authors explain how to use it for task assignment and work organization, decision-making under certainty and the securities...
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...
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...
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