The article considers the results of development of water treatment technology for household drinking water in Semey, presents a comparative analysis of widely used disinfectants, and considers technological schemes for water disinfection with chlorine dioxide and a combined disinfectant " chlorine dioxide and chlorine".
Keywords: household drinking water, disinfectants, chlorine
In the article we discuss temperature errors caused by non-stationary thermal processes in a thin-film Hall transducer. When solving the heat conduction equation we show the significant influence of effects of Peltier and Seebeck on the Hall voltage measurement results in the current switching mode. A new twenty-step switching currents algorithm for the Hall transducer is proposed. In this algorithm the additional voltages are measured at the absence of current through the transducer. From the additional voltages we estimate the contribution of the temperature drift. It was experimentally shown that for the PHE602117 converter the additive temperature error decreases by 30 times in comparison with the four-step algorithm while reducing performance by 20%.
Keywords: Hall transducer, additive error, Peltier effect, non-stationary processes, thermo-emf., magnetic measurements, current switching
The problem of recognition of defects in the surface layer of polished raceways of bearing rings according to the fractal dimension of the signals of the eddy current sensor is considered
Keywords: fractal dimension, defect recognition, recognition algorithm
The issue of quality, reliability and safety of the final products is under consideration. Process approach is the base of quality control system, and mon-itoring program is regarded for illustrative purposes.
Keywords: Quality, processor approach, quality management, monitoring
The paper is devoted by studying of the correctness of the antenna pattern adaptive control problem in a randomly inhomogeneous medium. We use spectral methods for the solving the Helmholtz equation with variable parameters in the frozen medium approximation. We have proved the correctness of the problem of a given antenna pattern forming in a randomly inhomogeneous medium for the measured distribution of the complex wave amplitude in the plane of receivers in the first time. The possibility of using an antenna with a synthesized aperture for adaptive correction of the antenna pattern for maximization of communication channel capacity is substantiated. We use the refractive index model as the sum of the deterministic and random components in numerical modeling. The sampling intervals were chosen in accordance with the sampling theorem. The analytic expressions with given parameters were used as a model of the law of the antenna array operation. The results of numerical simulation confirmed that, in the first approximation, the problem of the antenna pattern controlling of a transmitter with a synthesized aperture based on the distribution of the complex wave amplitude measured in the plane of receivers is correct. It allows to create a system of adaptive antenna pattern correction for maximization of communication channel capacity.
Keywords: communication channel, directional pattern, complex amplitude, synthesized aperture, angular spectrum method, adaptive control
The paper proposes a modification of earlier mentioned method reduces the number of computing operations and improve the accuracy of estimating the phase shift, which is close to the limit set by the Cramer-Rao inequality. The article also presents the results of numerical modeling of systematic and random errors parametric estimation of the phase shift angle of the proposed method.
Keywords: phase shift quasi-harmonic signal, Cramer-Rao lower band, parametric method
In the paper the Vlasov equation solution is considered for a case of stationary, homogeneous, isotropic and weakly nonlinear magnetoactive plasma-like media by successive approximations technique. An expression for the quasi-linear conductivity is obtained, which at low magnetic field ceases to depend on the electric field. It is shown that the quasi-linear conductivity matrix is symmetric, and its elements satisfy the classical reciprocal relations. The obtained relations can be applied in the design of magnetic microelectronics devices, for example, to improve the metrological characteristics of the digital Hall magnetometer.
Keywords: reciprocal relations, nonlinearity, plasma-like media, kinetic coefficients, quasi-linear conductivity
Questions of use of the device of the correlation analysis for an assessment of an error of a form of details of cars in cross section are considered. It is shown that use of the considered device also effectively as well as application of traditional methods of an assessment of an error of a form, however demands smaller computing expenses
Keywords: error, form, details, correlation, analysis
In this work new circuit solutions of R-S-latch and D-trigger having nonvolatile electrically programmable memory and nonvolatile shift register are presented. It shows that nonvolatile R-S-latch can be effectively used as a memory cell and simultaneously as write and read circuits for it, thus it makes possible to increase reliability of read operation from EEPROM at the expense of differential read for every bit.
Keywords: CMOS, R-S-latch, D-tirgger, shift register, EEPROM, nonvolatile memory
The article describes the preparation of the sensitivity of the output voltage for a typical architecture of voltage reference to variations of the parameters of elements. Also considers the main advantages of this approach in the analysis and design of circuits. The article presents the corresponding graphs sensitivities. Based on the findings conclusions about the impact of deviations of circuit elements on the output parameters of the reference voltage was done.
Keywords: Sensitivity, CMOS voltage reference, bias voltage, group bias
The method of digital parametric measurement of the phase shift of signals with slowly varying amplitudes of the same slowly varying instantaneous frequencies was proposed. The numerical simulations and experiments on the developed hardware and software system were carried out. The error of measurement the phase difference of harmonic signals in the experiments were not more than 0,00001 radian. The method can be used in applications where the measured value is expressed in terms of the phase difference of quasi-harmonic signals.
Keywords: quasi-harmonic signal, phase shift, real time measurements, hardware and software system
Main disadvantages of a dark image are considered. Alternative algorithm of improving dark images is proposed.
Keywords: Preliminary processing, digital image analysis, digital image improvement, Gaussian noise, dark images.
This paper describes a hardware-based and software system parametric estimation of signals. It`s experimental accuracy was achieved measuring the phase difference between the two quasi-harmonic signals at 10 μrad.
Keywords: parametric analysis, technical diagnostics, the phase difference
Considered part of the software and hardware designed and manufactured the device for the automatic analysis of nonlinear parameters of high-temperature superconducting ceramics YBa2Cu3O7-x in variable magnetic fields. Shows the calibration and specifications. The new is a synchronous (the error in determining the phase of no more than 0.5%) of digital signal samples of the nonlinear response of the sample and the samples generated by an external magnetic field (the error is less than 1%), with the number of data samples per channel to 90 ∙ 106 12-bit samples and sampling 600 ∙ 103 samples per second. The reference range of variable magnetic fields 1 - 50 Oe, a frequency range of 1 - 50 kHz in steps of 1 Hz and the accuracy of 0.0291 Hz. The device has an interface to the computer via two USB-interface and original software to work with it. With the use of the device, a series of experiments designed to produce some non-linear parameters of cylindrical sample made of high-Tc ceramic YBa2Cu3O7-x. The analysis of the results and their comparison with the presented in the literature
Keywords: Nonlinear medium, high-temperature superconducting ceramics, synchronous samples, harmonics, ARM-9 CPU, a differential sensor.
A compact digital voltammograph for electrochemical analysis of aqueous solutions was created. Device’s construction and drawings of the electrochemical cell for the studying of small amounts of fluids are described. Electronic circuits are assembled on modern high-precision components. The device implemented using cyclic, normal pulse and differential pulse voltammetry. Experiments were carried out with solutions of copper ions and hydrogen peroxide to test operability and characteristics of the voltammograph. All implemented methods gave reproducible results that are consistent with the theory. Typical results of the experiments with solutions of copper ions are shown.
Keywords: voltammetry, voltammograph, voltammogram, electrochemical cell, analysis of solutions