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The expediency of the implementation of the principle of steam thermal compression to improve the energy efficiency of sources of electricity and heat supply of small heat power engineering is substantiated. The results of thermodynamic analysis and numerical optimization of the parameters of the compressor steam-turbine cycle of a small cogeneration power plant are presented. A jet step-down thermotransformer has been tested - as an alternative to traditional boiler heating. On the basis of the conducted thermodynamic analysis, a new combined cycle of a step-down thermotransformer has been developed, which ensures efficient conversion of the supplied energy (mainly in the form of fuel heat) into the heat carrier flow of the heat supply system with the required temperature level 50 ... 90 °C). The fundamental difference between the considered thermal transformer and steam compressor heat pumps is the replacement of a mechanical compressor with a steam thermocompressor module (STC-unit). The working process in the STK-module is realized by using the liquid phase of the refrigerant, which boils up during expiration, subcooled to saturation, as an active medium of a jet compressor. Injection of steam from the evaporator is provided due to the fine-dispersed vapor-droplet structure formed in the outlet section of the active flow nozzle. A program for the numerical study of the working process of a step-down thermal transformer was prepared and tested, on the basis of which multivariate calculations were carried out. On the basis of computational studies, the area of achievable indicators of the proposed heat supply system has been established; the area of initial operating parameters corresponding to the maximum values of the conversion coefficient and exergy efficiency was determined; comparative indicators of the main parameters of the investigated thermal transformer on various working substances in the range of operating modes as a heat pump or a refrigerating machine were obtained. Key words : workflow, steam thermocompressor, step-down thermotransformer, energy efficiency, heat pump mode

This paper is devoted to the investigation of the effect of nitrogen and carbon content, as well as different temperatures of isothermal holding,—on the structural-phase state evolution of the quenched low-activation 12% chromium ferritic–martensitic steel. Basic temperature ranges within which the structural-phase state of the quenched steel changes upon heating have been found using the differential scanning calorimetry technique. Correlations between changes in the fine atomic structure of steel and structural-phase transformations during isothermal heating have been established by Mossbauer spectroscopy.

In Tokamak á Configuration Variable (TCV), unstable modes excited by resonant interaction between the shear Alfvèn waves in continuum gaps and energetic particles have been observed in scenarios with neutral beam injection (NBI). TCV is a middle-size device ( R 0 / a = 0.88 / 0.25 ) equipped with a 1 MW , 25 keV tangential neutral beam injector. In this paper the phenomenology of modes excited with on-axis NBI is presented. The Alfvènic nature of the modes has been confirmed investigating their sensitivity against plasma parameters such as NBI energy, toroidal magnetic field, and cross-checking with the predictions from linear kinetic stability code. The mode radial profile is estimated using electron cyclotron emission measurement and agrees well with modelling results. In addition, the fast particle distribution function has been modelled using TRANSP/NUBEAM code. Even with counter-current NBI (leading to higher losses), the drive from the resonant particles is sufficient for the mode excitation. An ad-hoc additional diffusion model allows to estimate the fast particle transport, modifying the fast particle gradient at the mode location and matching the neutron rates.

Interactions in lanthanide—amino acid—β-cyclodextrin systems (amino acid = tryptophan, phenylalanine; lanthanide = Eu3+, Pr3+) were studied in aqueous solution. An analysis of the chemical shifts observed in the 1H NMR spectra, as well as the ROESY data suggest the possibility for amino acid—lanthanide ion complexes encapsulated in the β-cyclodextrin cavity to form in solution. According to ROESY data, the indole ring of tryptophan and the phenyl group of phenylalanine enter the β-CD cavity from the wide rim side. Coordination with the metal ion occurs through the amino acid carboxyl group.

At present, the majority of Yamal oilfields are characterized by low debits. That is why geotechnical jobs (GTJ) are conducted here to increase oil production. Thus, this article analyzes predicted and actual efficiency of GTJ on nineteen Yamal oilfields in 2010-2017. Therefore, the purpose of the article is to provide information on the quantity and efficiency of GTJ on Yamal oilfields as well as to interpret the results obtained. The question is how reservoir rock fractures influence GTJ. So, much attention is given to the efficiency of hydraulic fracturing operation (HFO) in relation to the rate of field tectonical diversity. In fact, our analysis shows that physical and chemical methods take the leading place among the quantity of actual operations. It was also found that the biggest incremental oil production was obtained from drilling horizontal drain holes, but the smallest quantity – from remedial cementing. Furthermore, the results presented here show the dependence of HFO efficiency on the rate of field diversity. In conclusion, actual data prove that double permeability of reservoir rock increases the efficiency of well perforation, HFO and physical and chemical methods as well as its dependence on the rate of field diversity. The findings are of direct practical relevance.

The effect of synthesis conditions (type of cations, annealing temperature, reductive or oxidative atmosphere) on the chemical composition and structure of compounds formed in the MO2–CeO2/Ce2O3 systems (M = Zr, Hf) was studied by X-ray diffraction, X-ray absorption spectroscopy, Raman spectroscopy, and thermogravimetric analysis. The isothermal annealing of the precursors at temperatures below 1000°C in air gives Ce0.5M0.5O2 powders with fluorite type cubic structure (space group Fm3m). High-temperature annealing above 1000°C gives rise to additional tetragonal (space group P42/nmc) (for zirconates) or monoclinic (space group P21/a) (for hafnates) phases. The annealing in a hydrogen atmosphere affords the compounds Ce 2 4+ Ce 2-2 3+ M2O7 + x with an intermediate oxidation state of cerium and the x value depending on both the reduction conditions and the pre-annealing parameters. Vacuum annealing at 1400°C considerably decreases the content of Ce(IV) in the samples and affords a pyrochlore structure (space group Fd3m) with predominating Ce(III) cations.

The aim of the work is to study demographic and clinical features of intussusception in children. Material and methods. A retrospective analysis of all intussusception patients, who received treatment at the “Ivano-Matreninskaya Children’s Clinical Hospital” in Irkutsk over the period from 2006 to 2016. The age, gender of patients, the prescription of the disease, seasonality, diagnostic methods, treatment methods and outcomes (recovery, relapse of intussusception) were taken into account. Results. Over the past 10 years, there were observed 268 intussusception children patients. The number of cases per year varied from 11 to 41 with an annual increase in the last 5 years. At the age of 1 year there were 44 (16.4%) patients, over the year - 224 (83.6%). Boys are more often ill (191 (71.3%)) in comparison with girls (77 (28.7%)). There was no regular correlation between the frequency of the intussusception and the time of year. The peak incidence was observed in the summer (29.5%) with the fall in autumn (22.7%) and approximately the same ratio in winter and spring (23.4% and 24.4%, respectively). 204 (76.1%) patients entered up to 12 hours from the onset of the disease, 35 cases (13.1%) - from 12 to 24 hours, 29 patients (10.8%) entered after 24 hours. A clinical feature of intussusception was an increase in the number of cases of recurrent forms, whose frequency accounted of 14.5%. After conservative treatment, the relapse rate was 17.8%, after surgery - 2.5% (p

Analysis has been made of the possibilities of using uncooled and cooled optical elements, for example, laser mirrors with restricted motion of the optical surface. A simple method comparing and choosing the heat exchanger of the mirror and the mirror itself is proposed.

The authors have performed calculation and an analysis of the thermally stressed state of optical elements (mirror, passage windows, and beam splitters). A study has been made of the temperature fields, stresses, bending thermal displacements, and expansions of the optical surface of these elements under inhomogeneous local conditions of their loading depending on the defects existing in them.

Inclusion complex of 4-acetoxy-1-(2-ethoxyethyl)-4-phenylpiperidine with β-cyclodextrin was synthesized. Composition (1:2) and the structure of the complex were confirmed by NMR spectroscopy and thermal analysis. The results of pharmacological studies showed that the compound is of interest for in-depth testing, because of its deeper and more prolonged conduction anaesthesia, terminal (superficial) and infiltration anaesthesia along with less acute toxicity compared to the reference preparations.

3D mapping techniques have a large variety of applications from entertainment to military and medical fields. However, there is a big challenge of obtaining well refined 3D model from a set of images without usage of depth sensors. In the paper, we analyze main components of 3D reconstruction pipeline allowing to get detailed models of outdoor objects from drones. In particular, we experiment with algorithms required for structure from motion and point cloud densification. It is demonstrated, that proper local feature extraction, matching and verification directly effect on a final model quality. Analysis of two existing 3D reconstruction frameworks (MVE and COLMAP) is conducted. Initial experimental results are shown.

Specific features of the structure of the synthesized inclusion complex of 4-acetoxy-1-(2ethoxyethyl)-4-phenylpiperidine with β-cyclodextrin were considered. The composition (1: 2) and structure of the obtained complex were confirmed by NMR spectroscopy, thermal analysis, and quantum chemical calculations.

Cerium monoaluminate Ce1-x3+ Cex4+ AlO3+x/2 powders with low contents of Ce4+ cations (х ~ 0.052) were synthesized. A set of modern local structure sensitive methods of analysis, including X-ray absorption spectroscopy and Raman spectroscopy, were used to study the crystal, local, and electronic structures of the synthesized compounds. The degree of reduction and the thermal stability to oxidation of reduced powders depend not only on the reduction conditions but also on the conditions of heat pretreatment of the initial samples. It was concluded that the reaction 4CeAlO3 + O2 ↔ 4CeO2 + 2Al2O3 is reversible.

In the paper, two examples of embedded vision m odules are described. Firstly, it is demonstrated how fiducial marker tracking algorithm can be adopted for operation on Raspberry Pi. Usage of proposed ideas allows to achieve around 60fps speed of binary marker tracking. Secondly, we describe the problem of text detection and recognition in outdoor environment. Experimental results indicate on acceptable results and good potential to provide low-cost and efficient embedded vision system for this purpose. Technical details of both embedded vision modules are comprehensively discussed.

A method is developed for measuring the content of hydrogen (2Н) and oxygen (17O) isotopes in liquid media based on quantitative nuclear magnetic resonance. It has been established that the shifting europium trifluoromethanesulfonate (III) reagent is the most appropriate chemical compound for a reference sample to study the isotopic composition of aqueous solutions. A dependence of the paramagnetic chemical shift of 2Н and 17O nuclei on the concentration of Eu3+ ions in a solution is studied.

Processes connected with the diffusion of oxygen in targets for the laser ablation of a superconductive ceramics of composition YBa2Cu3O7 − x have been investigated by the methods of thermal analysis. A two-step mechanism of oxygen diffusion upon isothermal annealings in air has been revealed, which is explained by the incorporation of atmospheric oxygen into different positions, namely, into the interstices and directly into the sites of the crystal lattice.

Augmented reality is popular and rapidly growing direction. It is successfully used in medicine, education, engineering and entertainment. In the paper, basic principles of typical augmented reality system are described. An efficient hybrid visual tracking algorithm is proposed. The approach is based on combining of the optical flow technique with direct tracking methods. It is demonstrated that developed technique allows to achieve stable and precise results. Comparative experimental results are included.

Nowadays automatic methods based on artificial intelligence are rapidly growing. In the paper, a problem of automatic target recognition in synthetic aperture radar images is described. It is demonstrated, that two different machine learning instruments can provide very high classification accuracy. In particular, support vector machines with proper optimization and developed local feature set gives competitive results. Secondly, a novel architecture of convolutional neural network is proposed. Important practical aspects of both methods are analyzed. Experimental results for MSTAR are given.

SAR is a very popular instrument for imaging of the ground surface. Possibility of high-resolution image formation makes it superior tool for various information extraction tasks. In the paper, a problem of automatic target recognition is comprehensively analyzed. An idea of azimuth and range target profiles fusion is proposed. It is demonstrated, that usage of a proper image preprocessing with appropriate feature extraction steps allow to achieve a competitive recognition accuracy while keeping a low-dimensionality of feature vectors. Experimental results are discussed for a publicly available MSTAR dataset.

Synthetic aperture radar (SAR) is a powerful tool for remote sensing of the Earth surface. In the paper, several applications of pattern detection and recognition algorithms for extraction of information from SAR images are discussed. In particular, an idea of usage of optical flow techniques for automatic estimation of the moving target displacements from a sequence of single-look SAR images is proposed. It is shown, how this technique can be adopted for SAR imagery. In addition, it is demonstrated that local feature descriptors can be used for automatic SAR panorama creation without information about reference platform orientation. Finally, a problem of automatic target recognition is analyzed. It is shown, that a fusion of azimuth and range profiles of the ground target allows to achieve a competitive accuracy using quite compact feature vectors.

The idea for automatic extraction of the moving target parameters using single-antenna synthetic aperture radar is proposed. The displacements of the target are estimated from the sequence of the single-look SAR images using the Lucas-Kanade optical flow technique. It is shown that both moving target location in the SAR look and its shift direction can be extracted. In addition, the linear road segments are automatically detected from the multi-look SAR image using the Canny edge map and local pixels intensity gradient analysis. Proposed ideas are incorporated into the novel algorithm capable to unambiguously extract the moving target parameters using the single-antenna SAR system. Experimental examples obtained with X-band airborne SAR system are illustrated as well.

Synthetic aperture radar is a very popular and widely used instrument for various remote sensing tasks. In the paper, we propose several novel ideas for improvement of the efficiency of the modern SAR systems. At first, the problem of the automatic image stitching is considered. Instead of the common cross-correlation based solution the local features detection and description techniques are proposed. Secondly, we analyze the problem of the moving target parameters estimation. It is shown that the optical flow techniques can be used for the automatic extraction of the moving target shifts from the sequence of SAR looks. Experimental examples with real SAR data are illustrated and comprehensively discussed.

Random phthalide-containing poly(arylene ether ketones) have been synthesized. The properties of the polymers have been studied by the thermostimulated-current and thermostimulated-depolarization methods. An extremal dependence of the electrophysical properties on the content of phthalide groups in macromolecules is observed with a maximum at their concentration of 10–15%. These dependences are explained in terms of the Sworakowski model in which the role of polarization energy of phthalide-containing molecular fragments is distinguished. The feasibility of targeted variations in the electrophysical properties of nonconjugated polymers through incorporation of functional blocks into them is discussed.

Exchange reactions that may proceed in the course of polycondensation during formation of a polymer from 4,4′-difluorobenzophenone and 4,4′-(isopropylidene)diphenol have been studied. It has been shown that the molecular mass of the polymer decreases under the action of 4,4′-(isopropylidene)diphenol diphenolate. The nucleophilic substitution of the activated aryl halide in DMAA in the presence of potassium carbonate yields high-molecular-mass block copoly(arylene ether ketones) based on 4,4′-difluorobenzophenone and a number of bisphenols. It was demonstrated the synthetic procedure and the chemical structure of block copoly(arylene ether ketones) strongly affect the onset temperature of softening and the mechanical characteristics of the films based on these polymers.

Synthetic aperture radar is a popular instrument for high-resolution imaging. Usage of state-of-the-art image and signal processing solutions allows to significantly increase the efficiency of such systems. In the paper two important applications of computer vision algorithms are described. In particular, usage of local feature extraction algorithms for the radar image stitching. This results in the automatical panorama creation without usage of the navigation data. In addition, the road location approach based on the stroke width transform and contour analysis is proposed. Application of the developed methods is illustrated with real SAR data examples.

Poly(arylene ether ketones) with preset molecular weights (reduced viscosity from 0. 2 to 0.82 dL g−1) containing terminal phenolic groups were synthesized by the reactions of 4,4′-difluorobenzophenone with bisphenol A or phenolphthalein in the presence of K2CO3 in N,N-dimethylacetamide. The influence of an excess of bisphenols on the molecular weights of the polymers obtained was studied. The structures of the polymers were confirmed by 1H NMR spectroscopy. The molecular weight distributions of the polymers were determined.

The effect of neutral gas puffing in ELMy H-mode plasmas is studied using integrated predictive transport modelling, which is needed because of the strong link between the plasma core, the edge transport barrier and the scrape-off layer. Self-consistent results are obtained by coupling the one-dimensional core transport code JETTO with the two-dimensional edge code EDGE2D. In addition, magnetohydrodynamic (MHD) stability analysis is performed on the output of the transport simulations. The results of the MHD stability analysis is used to adjust MHD stability limits in the transport modelling, so that there is a feedback loop between the transport codes and the MHD stability codes. It is shown that strong gas puffing causes a sequence of causalities involving edge density, collisionality, bootstrap current, total edge current and magnetic shear, eventually triggering a transition from second to first ideal (or resistive) n =∞ ballooning stability. Qualitatively, the transition from second to first ballooning stability resembles the experimentally observed transition from type I to type III ELMy H-mode with the accompanying increase in ELM frequency and deterioration of plasma confinement.

Recent experimental results and plasma edge stability studies of ELMs are presented for both H-mode and optimized shear (OS) plasmas in JET. High triangularity (δ~0.5) ELMy \mbox{H-mode} experiments in JET achieved simultaneously high confinement (HIPB(y,2) = 1) and high density (~0.9 nGR). At high pedestal density (~1.1nGR), an anomalous decrease of type I ELMs frequency and energy losses per ELM was observed. A specific for high triangularity and high density (δ~0.5 and ne~1.1nGR) MHD activity with broad-band frequency spectrum (

Results achieved on JET during the 1997-1999 experimental campaigns in the physics of energetic ions and runaway electrons are reviewed. Heating of deuterium-tritium (DT) plasmas by fusion born alpha particles is found to be similar to that achieved by comparable ICRF heating of deuterium plasmas. The stability of alpha particle driven Alfv?n eigenmodes (AEs) in the highest fusion power ELM-free H mode discharges is shown to be consistent with the existing theoretical analysis for AEs. Direct measurements of the trapped alpha particle and knock-on deuteron distribution functions by a neutral particle analyser (NPA) are described. New ICRF heating scenarios tested in JET DT plasmas are presented in view of the possible use of the ICRF heating of ITER-like DT plasmas on route to ignition. The energetic ion pinch in the presence of toroidally asymmetric ICRF waves is studied experimentally on JET. Recent experimentally observed effects of ICRF accelerated ions on sawteeth in JET are reviewed. Detailed time and space resolved X ray images of the electron runaway beam in flight spontaneously generated by disruptions on JET are described.

A novel type of ideal toroidal Alfven eigenmode, localized in the low‐shear core region of a tokamak plasma, is shown to exist, whose frequency is near the upper continuum of the toroidal Alfven gap. This mode converts to a kinetic‐type toroidal Alfven eigenmode above a critical threshold that depends on aspect ratio, pressure gradient, and shear. Opposite to the usual ideal toroidal Alfven eigenmode, this new mode is peaked in amplitude on the small‐major‐radius side of the plasma.

Influence of synthesis conditions (type of atmosphere, reduction and oxidation, annealing temperature) on the chemical composition and structure of the compounds formed in the "ZrO2 - Ce2O3 / CeO2" system has been investigated by X-ray absorption fine structure (XAFS) spectroscopy combined with X-ray diffraction (XRD) and thermogravimetric analysis (TGA). It is revealed that isothermal annealing of precursor at temperatures less than 1000 °C in air leads to formation of Ce0.5Zr0.5O2 powders with cubic fluorite-type structure (Fm-3m). Further increase of annealing temperatures above 1000 °C causes decomposition of formed crystal structure into two phases: cubic and tetragonal. Annealing in reduction hydrogen atmosphere causes formation of Ce4 + 2xCe3 + 2-2xZr2O7 + x compounds with intermediate valency of cerium, where value of x depends on the reducing conditions and treatment parameters of precursor. Annealing in vacuum at 1400 °C strongly reduces the content of Ce4+ in a powder samples and leads to formation of pyrochlore structure (space group Fd-3m) with practically Ce3+ valence state.

The real-time reconstruction of the plasma magnetic equilibrium in a Tokamak is a key point to access high performance regimes. Indeed, the shape of the plasma current density profile is a direct output of the reconstruction and has a leading effect for reaching a steadystate high performance regime of operation. We have seen in particular that non monotonic current density profiles can trigger enhanced particles and heat confinement. On top of this the current density profile has a resistive diffusion time and any variation of the current drive systems takes some time to be efficient. The challenge is thus to develop methods and algorithms that reconstruct the magnetic equilibrium in the perspective to use these outputs for feedback control purposes.

Internal radial redistribution of MeV energy ICRF-driven hydrogen minority ions was inferred from neutral particle analyzer measurements during large amplitude MHD activity leading to internal reconnection in Shear Optimized plasmas in the Joint European Torus (JET). A theory is developed for energetic ion redistribution during a reconnection driven by an m=2/n=1 internal kink mode. Plasma motion during reconnection generates an electric field which can change the energy and radial position of the energetic ions. The magnitude of ion energy change depends on the value of the safety factor at the plasma core from which the energetic ions are redistributed. A relation is found for corresponding change in canonical momentum. P(subscript phi), which leads to radial displacement of the ions. The model yields distinctive new features of energetic ion redistribution under such conditions. Predicted characteristics of ion redistribution are compared with the NPA measurements, and good correlation is found. Sometimes fast ions were transported to the plasma edge due to interaction with a long-lived magnetic island which developed after the reconnection and had chirping frequency in the laboratory frame. Convection of resonant ions trapped in a radially moving phase-space island is modeled to understand the physics of such events.

The RF-induced pinch of 3He minority ions has been observed in JET affecting the dia- magnetic energy, the fast ion energy content, the sawtooth period, the Alfven eigenmode excitation and the y-emission. Further, the y-emission is consistent with RF-detrapping into co-current passing orbits. The results from the SELFO code are consistent with the observations.

Multiple weakly damped Alfven eigenmodes (AE) have been excited and detected by means of a dedicated active diagnostic in JET tokamak plasmas heated by ion cyclotron resonance heating, neutral beam injection heating, lower hybrid heating. and high plasma current Ohmic heating. This phenomenon is interpreted in terms of a new class of AE, the kinetic AE. predicted in theoretical models which include finite Larmor radius and toroidicity effects.

The current ramp-up phase of ITER demonstration discharges, performed at JET, is analysed and the capability of the empirical L-mode Bohm–gyroBohm and Coppi–Tang transport models as well as the theory-based GLF23 model to predict the temperature evolution in these discharges is examined. The analysed database includes ohmic (OH) plasmas with various current ramp rates and plasma densities and the L-mode plasmas with the ion cyclotron radio frequency (ICRF) and neutral beam injection (NBI) heating performed at various ICRF resonance positions and NBI heating powers. The emphasis of this analysis is a data consistency test, which is particularly important here because some parameters, useful for the transport model validation, are not measured in OH and ICRF heated plasmas (e.g. ion temperature, effective charge). The sensitivity of the predictive accuracy of the transport models to the unmeasured data is estimated. It is found that the Bohm–gyroBohm model satisfactorily predicts the temperature evolution in discharges with central heating (the rms deviation between the simulated and measured temperature is within 15%), but underestimates the thermal electron transport in the OH and off-axis ICRF heated discharges. The Coppi–Tang model strongly underestimates the thermal transport in all discharges considered. A re-normalization of these empirical models for improving their predictive capability is proposed. The GLF23 model, strongly dependent on the ion temperature gradient and tested only for NBI heated discharges with measured ion temperatures, predicts accurately the temperature in the low power NBI heated discharge (rms < 10%) while the discrepancy with the data increases at high power. Based on the analysis of the JET discharges, the modelling of the current ramp-up phase for the H-mode ITER scenario is performed with particular emphasis on the sensitivity of the sawtooth-free duration of this phase to transport model.

The first experimental observation of a radio frequency (rf) wave-induced particle pinch of trapped ions has been made in experiments at the Joint European Torus with nearly on-axis high power toroidally asymmetric ICRF (ion cyclotron range of frequencies) heating. Significant differences have been detected in discharges when waves have been directed in opposite toroidal directions. In particular, fast-ion-driven Alfvén eigenmode activity, sawtooth behavior, and proton distribution functions have been found to be strongly affected. The analysis of the discharges shows that the observed differences are consistent with an ICRF-induced particle pinch predicted by theory.