No 12 (2016)
3-7 98
Abstract
Non-conventional methods for detecting and correcting errors of measurement data transmitted via communication channels having interferences are described, the basis of the synthesis of which is a mathematical tool of the applied theory of finite fields (CTCP). An example of information-telemetry software testing of aircraft shows the possibility of their application for an integrated solution of the existing telemetry problems.
7-10 138
Abstract
We propose a new method of calibration of SEM magnification in the range of from 10 to 50 000X using the gage block of 4 mm size and auxiliary structure. Auxiliary structure was made as relief structure on the silicon chip and comprises two pitch structures of 100 mm and 2 mm pitch value provided that total length of the first pitch structure is 4mm. The use of verified gage block assures traceability of calibration results to the primary standard of meter. Expanded uncertainty of our measurements for 1K, 10K and 50K magnification calibration is not more than 0,14% for SEM S-4800.
LINEAR AND ANGULAR MEASUREMENTS
11-14 102
Abstract
The approach to the processing of measuring information gained from high-precise measuring devices with random variations within several discreets is described. The formulas for estimation of the measured value are given. The example of application of the described approach is given.
15-18 117
Abstract
The article reviews the principles of photogrammetric measurements. The photogrammetric system camera calibration procedure and the method for estimation of calibration quality are described. The results of research on determination of the marker optimal spatial position in calibration process are presented.
19-24 99
Abstract
The influence of frequency dispersion in antenna-feeder tract on the properties of signals of differential frequency, when the distance is measured in free space, is investigated. The frequency dispersion leads to increasing of the measurement error and lowering of noise resistance. It is shown that simultaneous influence of the frequency dispersion and unwanted amplitude modulation ever more increases the error. The variants of Fourier transformations are proposed and investigated that allow to reduce the mentioned error. The qualitative estimates of the achieved result are given.
24-27 114
Abstract
A technique is described for tracking of an object position and orientation in an alternating magnetic field, produced by two horizontal coplanar flat coils. The algorithm is given for the calculating of position and orientation of the measurement module, comprising a triaxial alternating magnetic field sensor and triaxial MEMS accelerometer.
OPTICOPHYSICAL MEASUREMENTS
28-32 140
Abstract
The paper describes an empirical method for measuring the fixed pattern noise (FPN) of the IR matrix sensors of the smart system intended for detecting barriers to the movement of the train. The method exploits an image of railway sleepers as a reference image for calibration. The segmentation procedure selects the texture homogeneity levels that allow measurement of the photo-element transfer coefficients within each level. The experimental results have shown the advantage of the proposed method in comparison with the well-known 2-point FPN correction procedures.
TIME AND FREQUENCY MEASUREMENTS
33-35 86
Abstract
The first experimental research results of the pulsed optical pumping method intended for developing compact rubidium vapor cell frequency standard, comparable by performance stability with the passive hydrogen masers, are presented.
MECHANICAL MEASUREMENTS
36-39 94
Abstract
The new way of contactless measurement and analysis of parameters of vibrating moving of radio-electronic equipment elements is offered. The proof of the mathematical apparatus connecting parametres of a vibrating blurring trace of the round mark image with parametres of a vector of vibrodisplacement amplitude of the investigated point on a surface of radio-electronic equipment elements is adduced.
ELECTROMAGNETIC MEASUREMENTS
40-45 101
Abstract
Based on two Hall transducers a low-frequency magnetometer with a sensitivity of 2,5∙10-7 T/Hz1/2 has been designed. Using the device, the dependences of density of trapped magnetic flux in single-crystal samples of Bi2Sr2CaCu2O8+x and YBa2Cu3O7-x are shown.
45-48 114
Abstract
The dependence of the current in the measuring circuit of the detector of high-speed particles from microparticles of these parameters. On the analytical expressions for the calculation of the current in a series RC-circuit based theorem Ramo-Shockley received.
ACOUSTIC MEASUREMENTS
49-52 87
Abstract
Considered the issues of experimental investigation of oscillations spindles in machine tools by using a three-component sensors of vibrations. It is shown that their use improves the reliability of the measurements extends the spatial search positions of defects in the bearings, and allows analysis of the attractors of the vibrational motion, to assess the quality of Assembly of the bearing units and monitor their current status.
53-57 110
Abstract
The problem of measurement of speech signals pitch frequency is discussed. The existing pitch frequency measurement algorithms are presented, and the need to improve the measurement accuracy using adaptive processing techniques is proved. A new PF measurement algorithm based on the method of Complementary Ensemble Empirical Mode Decomposition is developed. The experimental studies of the developed algorithm are conducted, and the results prove the algorithm stability to the pitch frequency modulation and increase in PF measurement accuracy.
PHYSICOCHEMICAL MEASUREMENTS
58-61 81
Abstract
Justification of the use of an idealized mathematical model for control of moisture content by a grain dielcometric method is given, which graphically shows the electrophysical processes in grains occurring under the influence of an electric field, and its equivalent connection allows to express analytically the relation of humidity and electrical parameters, ε and σ, of grain. The analysis of some methods and means of effective use of the dielcometric method are presented. Different variants of their solution are presented on the example of the development of an electric device to control grain moisture with an accuracy no less than 0,1 %.
ISSN 0368-1025 (Print)
ISSN 2949-5237 (Online)
ISSN 2949-5237 (Online)