The last decades development of applied calculation methods of nuclear reactor thermal and hydraulic processes are marked by the rapid growth of the High Performance Computing (HPC), which contribute to the active introduction of Computational Fluid Dynamics (CFD). The use of such programs to justify technical and economic parameters and especially the safety of nuclear reactors requires comprehensive verification of mathematical models and CFD programs. The aim of the work was the development and adaptation of a measuring system having the characteristics necessary for its application in the verification test (experimental) facility. It’s main objective is to study the processes of coolant flow mixing with different physical properties (for example, the concentration of dissolved impurities) inside a large-scale reactor model. The basic method used for registration of the spatial concentration field in the mixing area is the method of spatial conductometry. I

n the course of the work, a measurement complex, including spatial conductometric sensors, a system of secondary converters and software, was created. Methods of calibration and normalization of measurement results are developed. Averaged concentration fields, nonstationary realizations of the measured local conductivity were obtained during the first experimental series, spectral and statistical analysis of the realizations were carried out.

The acquired data are compared with pretest CFD-calculations performed in the ANSYS CFX program. A joint analysis of the obtained results made it possible to identify the main regularities of the process under study, and to demonstrate the capabilities of the designed measuring system to receive the experimental data of the «CFD-quality» required for verification.

The carried out adaptation of spatial sensors allows to conduct a more extensive program of experimental tests, on the basis of which a databank and necessary generalizations will be created. The received information allows to answer a number of questions related to scaling up the results of CFD calculations at the fullscale parameters of pressurized nuclear reactors. 

In the paper the template synthesis of ferromagnetic (Fe, Co, Ni) nanotubes in the pores of track membranes were studied. The aim of this work was determination of nanotubes basic structural and magnetic parameters and demonstration of the possibility of application in the flexible electronics elements.

By electrochemical deposition, ferromagnetic nanotubes with a diameter of 110 nm and an aspect ratio of 100 were formed in the pores of polyethylene terephthalate track membranes. The morphology of the obtained nanostructures were studied by scanning electron microscopy, the elemental composition was determined by the energy-dispersion analysis. Using the X-ray structural analysis, the main parameters of the crystal structure were established: lattice type, lattice parameter and average crystallite size. The magnetic properties were studied by the method of vibrational magnetometry.

It was shown that in the selected conditions of synthesis without reference to the type of ferromagnetic metals nanotubes had the same dimensions – length, diameter and wall thickness. The produced nanotubes consisted of iron, cobalt and nickel, respectively without oxides impurities. Nanotubes had a polycrystalline structure of walls with a body-centered cubic (iron), face-centered cubic (cobalt and nickel) crystal lattice. According to the main magnetic parameters, nanotubes belonged to a group of soft magnetic materials. Also, the presence of magnetic anisotropy, which is caused by the features of crystalline structure and shape of the nanostructures.

Based on the analysis of structural and magnetic characteristics of ferromagnetic nanotubes which were synthesized in the pores of track membranes, were proposed the main principles of their using in the elements’ of flexible electronics constructing (magnetic field direction sensors and magnetic memory elements). 

Characteristics optimization of lasers used in different measuring systems is of great interest up to now. Diode-pumped microchip lasers is one of the most perspective ways for development of solid-state light sources with minimal size and weight together with low energy power consumption. Increasing of output power with good beam quality is rather difficult task for such type of lasers due to thermal effects in the gain crystal under high pump power.

The investigation results of continuous-wave longitudinally diode-pumped Yb:YAG microchip laser are presented. In the presented laser radiation from multiple pump laser diodes were focused into the separate zone in one gain crystal that provides simultaneous generation of multiple laser beams. The energy and spatial laser beam characteristics were investigated.

Influence of neighboring pumped regions on energy and spatial laser beams parameters both for separate and for sum laser output was observed. The dependences of laser output power from distance between neighboring pumped regions and their number were determined. Decreasing of laser output power was demonstrated with corresponding distance shortening between pumped regions and increasing their quantity with simultaneous improvement of laser beam quality.

Demonstrated mutual influence of neighboring pumped regions in the longitudinally diode pumped Yb:YAG microchip laser allow as to generate diffraction limited Gaussian beam with 2W of continuous-wave output power that 30 % higher than in case of one pumped zone. 

Surface-enhanced Raman scattering is a powerful method used in chemoand biosensorics. The aim of this work was to determine the relationship between the signal of Surface-enhanced Raman scattering and the shape of silver nanostructures under the influence of laser radiation with different power.

Plasmonic nanostructures were synthesized in silicon dioxide pores on monocrystalline silicon n-type substrate. The pores were formed using ion-track technology and selective chemical etching. Silver deposition was carried out by galvanic displacement method. Synthesis time was chosen as a parameter that allows controlling the shape of a silver deposit in the pores of silicon dioxide on the surface of single-crystal n-silicon during electrodeless deposition. Deposition time directly effects on the shape of metal nanostructures.

Analysis of the dynamics of changing the morphology of the metal deposit showed that as the deposition time increases, the metal evolves from individual metallic crystallites within the pores at a short deposition time to dendritic-like nanostructures at a long time. The dependence of the intensity of Surface-enhanced Raman scattering spectra on the shape of the silver deposit is studied at the powers of a green laser (λ = 532 nm) from 2.5 μW to 150 μW on the model dye analyte Rodamin 6G. The optimum shape of the silver deposit and laser power is analyzed from this point of view design of active surfaces for Surface-enhanced Raman scattering with nondestructive control of small concentrations of substances.

The silver nanostructures obtained in porous template SiO2 on n-type silicon substrate could be used as plasmon-active surfaces for nondestructive investigations of substances with low concentrations at low laser powers. 

The disadvantage of the electromagnetic-acoustic (EMA) method receiving ultrasonic waves are low efficiency. The traditional way to enhance its effectiveness is increase the bias field. The aim of the study was research the way to improve the efficiency of the EMA transformation, using a time-varying bias field.

The researches held with the help of a specially designed installation that allows the magnetization to be performed by a constant and alternating magnetic field (dynamic bias), synchronously with the passage of the received pulse. The object of the study were rods made of different grades of steel with a diameter of 4–6 mm, in which the symmetrical zero mode S0 of the rod wave was excited by the EMA method (in the frequency range of about 40 kHz). A comparative analysis of the amplitudes and form pulses of multiple reflections during static and dynamic reversal of magnetization and with a full cycle of magnetization reversal conducted.

The result of the efficiency measurements EMA reception during static and dynamic bias found a significant (up to 5 times) increase in the signal amplitude on the receiving transducer. Taking into account that the main contribution to the excitation mechanism and the reception mechanism made the magnetostrictive effect on low frecuncy, it can assumed that using a dynamic bias field is impacting significant on the effective mobility of magnetic domains (that is changes the dynamic magnetic susceptibility of the material). It is established that it is possible to monitor steel at lower values of the bias field, and, consequently, to reduce the mass dimensions of the magnetic system.

Thus, in the course of the researchers found of effect of dynamic bias and effect of dynamic bias increase acoustic pulse amplitude of the signal of the received EMA method. Using this method will improve the quality EMA testing by creating more efficient EMA transducer. Taking into account that the value of the detected effect depends significantly on the steel grade, we can assume its possible application in the methods of express analysis, estimation of structural and stressed states. 

Devices based on scintillation detector are highly sensitive to photon radiation and are widely used to measure the environment dose rate. Modernization of the measuring path to minimize the error in measuring the response of the detector to gamma radiation has already reached its technological ceiling and does not give the proper effect. More promising for this purpose are new methods of processing the obtained spectrometric information. The purpose of this work is the development of highly sensitive instruments based on scintillation detection units using a spectrometric method for calculating dose rate.

In this paper we consider the spectrometric method of dosimetry of gamma radiation based on the transformation of the measured instrumental spectrum. Using predetermined or measured functions of the detector response to the action of gamma radiation of a given energy and flux density, a certain function of the energy G(E) is determined. Using this function as the core of the integral transformation from the field to dose characteristic, it is possible to obtain the dose value directly from the current instrumentation spectrum. Applying the function G(E) to the energy distribution of the fluence of photon radiation in the environment, the total dose rate can be determined without information on the distribution of radioisotopes in the environment.

To determine G(E) by Monte-Carlo method instrumental response function of the scintillator detector to monoenergetic photon radiation sources as well as other characteristics are calculated. Then the whole full-scale energy range is divided into energy ranges for which the function G(E) is calculated using a linear interpolation.

Spectrometric method for dose calculation using the function G(E), which allows the use of scintillation detection units for a wide range of dosimetry applications is considered in the article. As well as describes the method of calculating this function by using Monte-Carlo methods and the features of its application. The results of the calculation function G(E) for the detection unit on the basis of NaI(Tl) detector (Ø40 mm, h = 40 mm) to use it as a comparator for kerma rate in the air certification of low intenseе photon radiation fields. 

The wide using of digital photography has led to significant progress in the development of the theory and methods of restoring the three-dimensional space picture on base of two-dimensional digital images. To solve the problem of increasing the measurements accuracy of such systems, it is necessary to take into account the influence of a number of destabilizing factors. The aim of this work was development of technique for accounting and compensating of destabilizing factors influence, such as the deviation from the horizontal position line of the stereo pair lens, the non-parallelism of the lenses optical axes, the mutual inclination of the photo detector matrices, and the distortion of the stereo camera optical system for increasing of the measurements accuracy of rangefinder based on the correlation analysis of the stereo image.

A software application has been developed for analyzing the optical distortions of serially produced lenses, which allows to visually demonstrate the distortions nature and to determine the polynomial coefficients for compensating of the optical distortion.It is obtained that for the Fujifilm FinePix Real 3D stereo camera the distortion of the digital image reaches ± 20–35 pixels at the edges of the photo detective matrix and is not the same for the first and second lenses. The difference in the optical distortion values is due to the unequal slope of the photo detector matrix to the optical axis of the objective. Compensating polynomials for the optical system distortions of the first and second lenses of the stereo camera are experimentally determined.

The range object expression from the stereo images taking into account the optical distortion compensation is obtained. It is shown for increasing of the measurements accuracy, the determining factor is not the absolute value of the lenses distortion, but the difference in the optical distortions of the stereo camera lenses, depending on the difference of the measured object coordinates of the on the photo detective matrices. Experimental studies of the developed technique for distortions compensation showed a decrease of the absolute measurements error more than by an order of magnitude at distances up to 100 m. 

High values of residual stresses is one of the most common reason of breaking lots of metal constructions, including rails. These stresses can reach values of flow limit, especially in the area of faults. Estimation of residual stresses values allows to get information about technical condition of the rail and also allow to avoid abnormal situations So, the aim of the research is creating the model of stress-strain state of the rail, which was hardened in its top and bottom, and to compare modeling results with experimental measurements of stresses and discrepancy of the housing.

For creating the model and making evaluations by finite element method we used a program COMSOL. Forces on the top and bottom of the rail cause tension stresses, forces on the web of the rail cause tensile stresses. We compared calculated values of stresses with discrepancy of the housing. The discrepancy of the housing is informative characteristic for estimating the residual stresses according to standards. For experimental measurements we used an acoustic structuroscope SEMA. This structuroscope uses the acoustoelastic phenomenon for measurements. We made measurements of the five rails.

According to the calculation results of the model, critical discrepancy of the housing in 2 mm corresponded to the following values of maximum stresses: –54 MPa in the top of the rail, 86 MPa in the web and –62 MPa in the bottom of the rail. Experimental measurements are the following: from –48 MPa to – 64 MPa in the top of the rail, 54 MPa to 93 MPa in the web of the rail, and –59 MPA to –74 MPa in the bottom of the rail. Absolute error was ±5 MPa.

Thus we created the model, which allowed to analyze strain-stress state and compare real values of stresses with discrepancy of the housing. Results of the modeling showed coincidence with structure of distribution of residual stresses in five probes of rails. 

Digital images provide to determine photometric and colorimetric properties of objects subject to validation all elements of a measuring channel (digital camera, software, display) and solve the problem of their limited dynamic ranges. The aim of the study was to explore the dynamic range of a digital camera for use in photometric and colorimetric measurements.

The Laboratory of Photonics at the Institute of Microelectronics and Optoelectronics (Warsaw Technical University, Poland) conducted a comparative experiment to determine the threshold of sensitivity, linearity and range of application the digital camera. Color target sets with certified brightness and chromaticity were created at the terminals and recorded with a digital camera with different exposure times. The authors propose a method to extend the dynamic range of a digital camera for red, green and blue color channel of intensities by pairing the calibration dependencies, and determine the true brightness and color of a point on the object by calculation.

Calibration dependencies (triads) of digital camera for red, green and blue color channels intensities were constructed. These dependences allow determining lower and upper bounds of the dynamic range. Each triad has a form of the hysteresis loop. The experiment showed that the accuracy of this method is ± 3–5 %. 

The field of high-energy gamma-ray for the calibration of radiation protection devices can be obtained by capturing thermal neutrons from titanium target (to 7 MeV) and nickel target (to 10 MeV). The aim of this work was to determine the metrological characteristics of capture gamma-ray fields from titanium target and nickel target obtained at the AT140 Neutron Calibration Facility to provide dosimetry up to 10 MeV.

We have chosen energy intervals in which we can calibrate dosimetry devices taking into account the accompanying generation of gamma-ray neutrons by the fast neutron source 238PuBe, the capture radiation of collimator materials and capture radiation from targets.

We measured air kerma rate with the aid of the reference AT5350 dosimeter with the ionization chamber TM32002. Using the Monte-Carlo simulation, we obtained the energy distribution of the air kerma rate for targets. We determined the geometric dimensions of the uniform field and the interval of operating distances of the facility.

We investigated the metrological characteristics of capture gamma-ray fields from titanium target and nickel target obtained at the AT140 Neutron Calibration Facility for dosimetric radiation protection devices. We showed that in such fields it is possible to calibrate dosimetry devices in the extended energy range up to 10 MeV. 

One of key elements of an engineering component quality management system of process of provision of sports and improving services in gyms is the subsystem of diagnostics of physical client state. The aim of the study was to increase in efficiency of functioning of a quality management system of process of provision of sports and improving services in gyms due to development of techniques of incorrect estimation of the initial client state.

The task of formation of a complex of indices of the initial status by criterion of necessary informtiveness is formulated. The principle of the functional interchangeability as a methodological basis for its decision is reasonable. The hierarchical structure of an integral assessment of the initial client state of gym is offered. On its basis the hierarchical model of rating of informtiveness of a complex of the single (measured) indices, the providing objectivity of an integral assessment of the initial status is developed. The correctness of model is provided at the expense of a formulation of a complex of assumptions and original technology of application of different methods of expert estimation.

The result of simulation of informtiveness of an integral assessment of the initial client state for a specific type of service and the purposes of physical enhancement includes: 1) library of sets of single indices, for each of which the technique and a monitoring aid, and also an informtiveness assessment in points, 2) the rules of support of the functional interchangeability of alternative complexes of indices by criterion of sufficiency of informtiveness of a complex based on additive models and the accepted restrictions is defined.

The concept of a technique of formation of a complex of the measured and (or) evaluated indices of the initial client state for the specific type of sports and improving service adapted under material opportunities of gym on the one hand, and responding to criterion of necessary informtiveness and the principle of the functional interchangeability, on the other hand is offered.