Vol 60, No 11 (2018)

Methods for reconstructing input signals of dynamical systems with distributed parameters based on nonparametric and parametric identification methods are considered. The proposed methods enable reconstruction of the input signals to within a computational error.

We describe a predictive method for monitoring the state of a turning tool during processing. The results of the prediction, based on phase-chronometric measurement information, are considered. The possibility of practical application of the described prediction technique in combination with phase-chronometric data is shown. We present an algorithm for predicting the actual wear of the tool using an example of simplest turning.

A complex of physical optics methods that includes x-ray phase analysis, colorimetry, and wavelet analysis is proposed. Weak structural responses of dispersed clay systems to the effect of microwave radiation are recorded by means of the complex. Through the use of a combination of x-ray phase analysis and colorimetric gradation, it is possible to establish phase and polymorphic conversions, and with the use of wavelet analysis, the evolution of the morphology of dispersed particles. The efficiency of the proposed complex of physical optics methods for studying secondary phase morphologies in the millimeter, micrometric, and submicrometric scales is demonstrated.

We describe a method for the determination of the parameters of vibration of the elements of rotating units of turbomachines. This method is based on the analysis of changes in the shape of the output signal of a primary transducer. The efficiency of the method is demonstrated for broad ranges of operating parameters of the oscillatory processes. We reveal possible problems in the realization of the method and propose some methods for their solution. We also study the accuracy characteristics of the proposed method for various signal-to-noise ratios of the output signal of primary transducer.

A methodology for timely monitoring of the electrophysical characteristics and parameters of a sealed cable gland based on inorganic materials is examined. The methodology is applied to assessing the quality of the status of the cable input during actual time of use of the cable line of nuclear physics facilities. The special features of connecting protective shielding systems (double shielding) of nuclear physics facilities are considered. A description of an experimental technique for using a gland for control cables is provided. The results of measuring wave resistance and the attenuation coefficient are analyzed using the quarter-wave short-circuit line method at the carrier frequency. It has been determined that the type of sealed cable gland that has been developed is stable with respect to electrophysical parameters under standard failure conditions and is applicable the input of control cables of nuclear physics facilities.

A modification is proposed for a method of measuring various physical quantities using the area under the resonance curve as an information parameter of the measurement resonator. The modified method consists of determining the amplitude-frequency characteristic (AFC) at a fixed frequency with variation of the initial resonant frequency of the resonator within fixed limits. In order to realize the modified method, deviation from the oscillation frequency of the generator is not required. The realization of the modified method is considered for measurements using waveguide resonators.

The problem of measuring the profile of the monoatomic multilayer surface of silicon nanostructures by an interference method is considered. The measurements are performed with the use of a Zygo New View 6200 white light scanning electron microscope from the Center of Collective Use for High-Precision Measurement Technologies in Photonics of the All-Russia Research Institute of Optophysical Measurements.

The geometric diagram of a bench for determining the instrument errors of high-precision two-dimensional optoelectronic goniometers is considered. These errors are found by measuring the angles between known spatially fixed reference directions and comparing the values obtained to the sizes of these angles measured by means of autocollimators oriented to a special caliber (calibrating prism) that fixes the point of intersection of the geometric axes of the controlled goniometer. The caliber standard is in the form of a multifaceted prism with reflective surfaces the normals to which form the required geometric diagram in space.

Two stages of statistical processing of the cross-sections of nonspherical particles are considered. The cross-sections are obtained from images of the particles with the use of non-normalized moments. The first stage is based on the relation between the first- and second-order non-normalized moments with the transmission coefficients and angular dimension of the halo produced by forward scattering of optical radiation. On the second stage, the parameters of the size distribution of the particles by cross-sectional area are recovered from the non-normalized moments up to fourth order with the use of the lognormal distribution.

The influence of the phase transitions in gas–liquid flows on the accuracy of reproduction of the discharge of gas–liquid mixtures under high pressures on test benches is analyzed. An algorithm for the numerical analysis of the phase equilibrium of mixtures of air with various concentrations of an Exxol oil substitute is developed with the use of the equations of state and the fundamental concepts of thermodynamics. The coefficients of binary interaction of the Exxol oil substitute and the main components of air (nitrogen, carbon dioxide, oxygen, and argon) are obtained. The experimental data and numerical results on the saturation of Exxol–air mixtures are presented for various concentrations. It is shown that if we neglect the phase transitions, then the information about the parameters of multiphase flows measured on testing benches becomes significantly distorted.

We analyze the possibility of measuring of weak low-frequency alternating magnetic fields against the background of geomagnetic variations and estimate the lower limits of detection of weak periodic and aperiodic signals of magnetic induction in the geomagnetic field by magnetomodulation sensors. It is shown that the components of magnetic induction of continuous geomagnetic noise measured in a narrow frequency band by two magnetomodulation sensors located at a distance greater than one meter are random and independent.

Questions on the development of an interlaboratory standard for checking national standards for the unit of pulsed electric field strength have been considered. The requirements for speed and sensitivity of an interlaboratory standard were defined and substantiated. It was proposed to implement an interlaboratory standard in the form of a stripline measuring transducer. A high-sensitivity transducer design was developed, and test studies of its characteristics that confirmed full compliance with the declared technical requirements were conducted.