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Abstract The ray statement of the inverse problem of determining three unknown variable coefficients in the linear acoustic equation is studied. These coefficients are assumed to differ from given constants only inside some bounded domain. There are point pulse sources and acoustic receivers on the boundary of this domain. Acoustic signals are measured by a receiver near the moment of time at which the signal from a source arrives at the receiver. It is shown that this information makes it possible to uniquely determine all the three desired coefficients. Algorithmically, the original inverse problem splits into three subproblems solved successively. One of them is a well-known inverse kinematic problem (of determining the speed of sound), while the other two lead to the same integral geometry problem for a family of geodesic lines determined by the speed of sound.

Rhabdomyolysis is a life-threatening skeletal muscle disease, the time of diagnosis and initiation of treatment of which directly affects the likelihood of developing acute kidney injury and the quality of recovery of muscle function. The ultrasound method of diagnostics is accessible and can be used at the stage of primary diagnosis, but it has low sensitivity of 68% and specificity of 57% when using such ultrasound symptoms as a diffuse expressed increase of echogenicity (homogeneous or heterogeneous), disorder of transverse striation of the muscle structure and high volume of the muscular tissue damage (over 30%). The possibility of ultrasonic elastography in the diagnosis of rhabdomyolysis in 95 patients admitted with suspected damage to muscle tissue are discussed. Comparison of the parameters of shear wave elastography in patients with rhabdomyolysis and patients with other diseases manifested by muscle edema (muscle contusion, inflammatory myopathies, post-exercise muscle edema), as well as with the control group, significant differences were noted (p 0.01) allows to determine the quantitative ultrasound characteristics of muscle tissue, pathognomonic for rhabdomyolysis. The use of shear wave elastography with obtaining lateral wave velocity of less than 1.64 m/s increased the sensitivity and specificity of the method in the diagnosis of rhabdomyolysis to 75 and 62%, respectively. A logit model with integrated use of elastography indices was developed, with a diagnostic accuracy of 77%. During muscle recovery, there was an increase in lateral wave velocity to the level of control group values, which can be used as one of the markers of patient recovery.

Abstract For the equation $${{u}_{{tt}}} - \Delta u - f(x,u) = 0, (x,t) \in {{\mathbb{R}}^{4}},$$ where $$f(x,u)$$ is a smooth function of its variables and is compact in x, the inverse problem of recovering this function from given information on solutions of Cauchy problems for the differential equation is studied. Plane waves with a strong front that propagate in a homogeneous medium in the direction of the unit vector ν and then impinge on an inhomogeneity localized inside some ball B(R) are considered. It is supposed that the solutions of the Cauchy problems can be measured on the boundary of this ball for all ν at times close to the arriving time of the front. The forward Cauchy problem is studied, and the existence of a unique bounded solution in a neighborhood of a characteristic wedge is stated. An amplitude formula for the derivative of the solution with respect to t on the front of the wave is derived. It is demonstrated that the solution of the inverse problem reduces to a series of X-ray tomography problems.

Self-assembled opal crystals (bulk silica opals and PMMA thin opal films)have been studied by atomic force microscopy (AFM) and optical spec-troscopy. Reflectance and transmittance spectra (R(λ) and T (λ), respectively)as well as spectra of ellipsometric parameters Ψ(λ) and Δ(λ)demonstratepronounced changes with changing the angle of light incidence. Diameters ofspheres obtained from AFM-images correspond to those obtained from Braggfit to the diffraction resonance dispersions. The band of light losses detected byellipsometry at the spectral range of avoided band crossing of opal eigenmodeswas assigned to the energy exchange between these modes

Given a hyperbolic equation with variable coefficients, we construct a regularizing algorithm to solve the problem of continuation of the wave field from the boundary of the half-plane inside it. We introduce some $$N$$ -approximate solutions and establish their convergence to the exact solution. Under consideration is the case when the problem data have an error of $$\delta $$ . We find an estimate of the accuracy of the approximate solutions and prove the convergence of the approximate solutions to the unique solution as $$\delta \to 0$$ .

An Erratum to this paper has been published: https://doi.org/10.1134/S106456242207002X

At the present time for sanatorium treatment of dorsopathies no morpho-pathogenetic principles are based on severity of degenerative spine changes. The choice of treatment modalities is provided according only to clinical signs and the fact of degenerative spine disease presence, in spite of limitations and contradictions to some resort procedures because of their mechanisms and peculiarities of therapeutic effects. Materials and methods. Comparison of complex imaging examination and sanatorium resort intensity regimen medical appointments of 952 patients with dorsopathies was provided depending on morphological pattern and severity of degenerative spine changes. Case histories, sanatorium medical outpatient cards and the results of radiologic imaging (computed tomography, magnetic resonance imaging, spondylography and osteodensitom-etry) were analyzed. Results. Three groups of sanatorium resort therapeutic action intensity (maximal, 376 patients; limited, 493 patients; and minimal, 83 patients) for patients with dorsopathies were established. The most significant morphological criteria of patient distribution into appropriate groups were established, such as bone mineral density state, the presence and severity of spinal osteoarthrosis and spondylolisthesis, vertebral-motor segment stability or instability, vertebral body hemangiomas. The size of intervertebral disc extrusions and grade of disc height decreasing played a secondary role. The value of spondylography, computed tomography, magnetic resonance imaging and dual-energy radioabsorptiometry in determination of these criteria is presented, as far as in imaging algorithm of examination of patients with dorsopathies on the pre-sanatorium stage, with calculation of computed tomography and magnetic resonance imaging sensitivity, specificity and accuracy. Discussion. Forming morpho-pathogenetic approach to sanatorium resort treatment of dorsopathy demands essential application of modern radiologic imaging modalities. The presence, type and severity of degenerative spine morphological changes must be as fundamental as clinical and neurological pattern, affecting sanatorium resort intensity regimen selection and treatment modalities and schemes. In basic cases most advisable radiologic imaging pre-sanatorium examination modality should be computed tomography, but others are also necessary to use when concretely indicated.

An Erratum to this paper has been published: https://doi.org/10.1134/S106456242234004X

For a system of electrodynamic equations, the inverse problem of determining an anisotropic conductivity is considered. It is supposed that the conductivity is described by a diagonal matrix σ(x) = $${\text{diag}}({{\sigma }_{1}}(x),{{\sigma }_{2}}(x)$$ , σ3(x)) with $$\sigma (x) = 0$$ outside of the domain Ω = $$\{ x \in {{\mathbb{R}}^{3}}|\left| x \right| < R\} $$ , $$R > 0$$ , and the permittivity e and the permeability μ of the medium are positive constants everywhere in $${{\mathbb{R}}^{3}}$$ . Plane waves coming from infinity and impinging on an inhomogeneity localized in Ω are considered. For the determination of the unknown functions $${{\sigma }_{1}}(x)$$ , $${{\sigma }_{2}}(x)$$ , and $${{\sigma }_{3}}(x)$$ , information related to the vector of electric intensity is given on the boundary S of the domain Ω. It is shown that this information reduces the inverse problem to three identical problems of X-ray tomography.

For the system of electrodynamics equations with anisotropic permittivity, the inverse problem of determining the permittivity is studied. It is supposed that the permittivity is characterized by a diagonal matrix $$\epsilon = {\text{diag}}({{\varepsilon }_{1}},{{\varepsilon }_{1}},{{\varepsilon }_{2}}),$$ where $${{\varepsilon }_{1}}$$ and $${{\varepsilon }_{2}}$$ are positive constants everywhere outside of a bounded domain $${{{\Omega }}_{0}} \subset {{\mathbb{R}}^{3}}$$. Time-periodic solutions of Maxwell’s equations related to two modes of plane waves coming from infinity and impinging on a local inhomogeneity located in $${{{\Omega }}_{0}}$$ are considered. For determining functions $${{\varepsilon }_{1}}(x)$$ and $${{\varepsilon }_{2}}(x),$$ some information on the magnitudes of the electric strength vectors of two interfering waves is given. It is shown that this information reduces the original problem to two inverse kinematic problems with incomplete data regarding travel times of electromagnetic waves. The linearized statement for these problems is investigated. It is shown that, in the linear approximation, the problem of determining $${{\varepsilon }_{1}}(x)$$ and $${{\varepsilon }_{2}}(x)$$ is reduced to two X-ray tomography problems.

Introduction. Rhabdomyolysis is destruction syndrome of striated skeletal muscle characterized by myalgia, an increase of creatine phosphokinase level (CPK), serum myoglobin and myoglobulinuria. This review presents the analysis of five cases of acute postexercise rhabdomyolysis happened to militaries, complicated by pigmentary nephropathy with the description of clinical and laboratory studies, magnetic resonance imaging (MRI), electroneuromyographic and morphological features. The purpose of the study is the clinical assessment of MRI for the diagnosis of postexercise rhabdomyolysis.Results. A comparative assessment demonstrated that in the presented clinical cases in the muscle groups with minimal edematous changes, an increase in the MR signal was observed at T2-WISPAIR, as well as in diffusion-weighted images (factor b — 0, 500, 1000), at the same time on all other pulse sequences (including STIR) changes in signal intensity were not detected. Conclusion. There was shown that in mild cases of rhabdomyolysis, the regression of MR manifestations corresponds to a decrease in laboratory parameters of CPK and myoglobin, whereas in severe forms of rhabdomyolysis, the regression of MR manifestations is significantly slowed down relative to laboratory indicators, and in the place of necrosis areas, the foci of degeneration form (hyperintensive on T1 and T2-WI, hypo-intensive on T1-WI-SPIR and T2-WI-SPAIR). Morphologically confirmed the fact of pronounced hemorrhage in the compartment syndrome due to postload rhabdomyolysis (hyperintensive sites on T1-WI and T1-WI-SPIR, iso-, hypointensive on T2-WI, T2-WI-SPAIR).

The system of equations of electrodynamics is considered for a nonmagnetic nonconducting medium. For this system, the problem is under study of determining the permittivity e from the given modulus of the electric intensity vector of the electromagnetic field that is the result of the interference of the two fields generated by some point sources of an extraneous current. It is assumed that permittivity is different from a given positive constant e0 only inside a compact domain Ω0 ⊂ ℝ3, whereas the modulus of the electric field intensity vector is given for all frequencies starting from a fixed frequency ω0 on the boundary S of some domain Ω that includes Ω0. It is shown that this information allows us to reduce the original problem to the well-known inverse kinematic problem of determining the refraction index inside Ω by the travel time of the electromagnetic wave between the points of the boundary of this domain. The algorithm for numerical solution of the inverse problem is constructed, and the test calculations on the simulated data are presented.

For nonmagnetic and nonconductive medium the system of electrodynamic equations that corresponds to periodic in time oscillations is considered. An inverse problem of determining permittivity in this system by the given module of the electric strength is studied. It is supposed that the electric fields is a result of the interference of two fields created by point sources. The permittivity e(x) is assumed to be differ from a given positive constant e0 inside of a compact domain W0 Ì R3 only. An information on module of the electric strength is given on the boundary of the domain W contained W0 inside itself and for all frequencies beginning with some fixed frequency w0. The asymptotic behavior of solution of a direct problem related to the electrodynamic equations is studied and the original inverse problem is reduced to the well known inverse kinematic problem. This reduction open a way for constructive solution of the inverse phaseless problem.

For fixed \begin{document} $y \in \mathbb{R}^3$ \end{document} , we consider the equation \begin{document} $L u+k^2u = - δ(x-y), \>x \in \mathbb{R}^3$ \end{document} , where \begin{document} $L=\text{div}(n(x)^{-2}\nabla)+q(x)$ \end{document} , \begin{document} $k >0$ \end{document} is a frequency, \begin{document} $n(x)$ \end{document} is a refraction index and \begin{document} $q(x)$ \end{document} is a potential. Assuming that the refraction index \begin{document} $n(x)$ \end{document} is different from \begin{document} $1$ \end{document} only inside a bounded compact domain \begin{document} $Ω$ \end{document} with a smooth boundary \begin{document} $S$ \end{document} and the potential \begin{document} $q(x)$ \end{document} vanishes outside of the same domain, we study an inverse problem of finding both coefficients inside \begin{document} $Ω$ \end{document} from some given information on solutions of the elliptic equation. Namely, it is supposed that the point source located at point \begin{document} $y \in S$ \end{document} is a variable parameter of the problem. Then for the solution \begin{document} $u(x,y,k)$ \end{document} of the above equation satisfying the radiation condition, we assume to be given the following phaseless information \begin{document} $f(x,y,k)=|u(x,y,k)|^2$ \end{document} for all \begin{document} $x,y \in S$ \end{document} and for all \begin{document} $k≥ k_0>0$ \end{document} , where \begin{document} $k_0$ \end{document} is some constant. We prove that this phaseless information uniquely determines both coefficients \begin{document} $n(x)$ \end{document} and \begin{document} $q(x)$ \end{document} inside \begin{document} $Ω$ \end{document} .

The possibilities of functional magnetic resonance imaging in the diagnosis of opioid dependence syndrome are considered. It is known that opioid addiction is one of the leading problems of modern narcology. Despite the fact that the number of researches of the neurobiological effects of opioids is increasing every year, the pathogenetic effects of dependence on this narcotic substance are still not fully understood. Functional magnetic resonance imaging rest allows one to assess the functional connectivity of the remote from each other parts of the brain and makes a great contribution to understanding the mechanisms of development of addictive disorders in general. In patients with opioid dependence, an analysis was made of the neural network of the passive mode of the brain (default mode network). This resting network is associated with the processes of control and thinking, including emotional and cognitive components, and consists of medial frontal regions, posterior cingulate sections, precuneus, lower parietal and temporal divisions. It was found that, in comparison with the control group, in all patients suffering from opioid dependence, weakened functional connections of all structures of the cerebro-spinal cord system (p0,05). In this case, changes in the medial prefrontal cortex and precuneus are more pronounced in patients who are in the state of opioid intoxication, and in the parietal-temporal regions in patients who are in a state of remission up to 1 month. The correlation of cortical structures responsible for the «behavior control» system (orbitofrontal cortex, prefrontal cortex) with subcortical structures responsible for emotions in the limbic system was also evaluated. In comparison with the control group, in patients with early remission, weakened functional connections between cortical structures and left contiguous nucleus, almond-shaped body from two sides. In patients in a state of intoxication in addition to these changes, the functional relationship between the orbital frontal cortex and the shell on the left has been weakened. The weakening of functional links in the network of the passive mode of the brain in the groups of drug addicts suggests that they have violated the processes of control, thinking and making the right decision. The resulting functional changes can form the basis for creating biomarker maps for patients suffering from opioid dependence, which can be used to guide and evaluate the treatment of this pathology.

Authors gratefully acknowledge valuable contributions of their collaborators and colleagues N. Gaponik, A. Eychmueller, A.L. Rogach, M. Bardosova, C.M. Sotomayor Torres, D.N. Chigrin, V.G. Solovyev, R. Kian and R. Zentel.

We report a measurement of the π- photoproduction beam asymmetry for the reaction γp→π-Δ++ using data from the GlueX experiment in the photon beam energy range 8.2-8.8 GeV. The asymmetry ς is measured as a function of four-momentum transfer t to the Δ++ and compared to phenomenological models. We find that ς varies as a function of t: negative at smaller values and positive at higher values of |t|. The reaction can be described theoretically by t-channel particle exchange requiring pseudoscalar, vector, and tensor intermediaries. In particular, this reaction requires charge exchange, allowing us to probe pion exchange and the significance of higher-order corrections to one-pion exchange at low momentum transfer. Constraining production mechanisms of conventional mesons may aid in the search for and study of unconventional mesons. This is the first measurement of the process at this energy. © 2021 American Physical Society.

Some regularization algorithm is proposed related to the problem of continuation of the wave field from the planar boundary into the half-plane. We consider a hyperbolic equation whose main part coincideswith the wave operator, whereas the lowest term contains a coefficient depending on the two spatial variables. The regularization algorithm is based on the quasi-reversibility method proposed by Lattes and Lions. We consider the solution of an auxiliary regularizing equation with a small parameter; the existence, the uniqueness, and the stability of the solution in the Cauchy data are proved. The convergence is substantiated of this solution to the exact solution as the small parameter vanishes. A solution of an auxiliary problem is constructed with the Cauchy data having some error. It is proved that, for a suitable choice of a small parameter, the approximate solution converges to the exact solution.

Status, utilization and perspectives of development of Russian mineral raw materials base of flux minerals (fluorite and flux limestone) considered, as well as refractory materials (bauxite, dolomite, magnesite, brucite, bischofite and zirconium) and moulding sands. An estimation of the level of provision with nonmetallic raw materials of Russian steel industry done. It was shown, that bowels of Russia have practically all kinds of nonmetallic minerals, used in the metallurgy of hot metal, steel and alloys. High alumina minerals are not used in metallurgy, despite discovered resources of them are big enough to meet demands of metallurgical plants of the country. There is some deficit of fluorite and zirconium, with no objective reasons for that.State of the markets of minerals considered briefly described.

Under consideration is the problem of continuation of the wave field from the boundary of a half-plane inside it. We obtain stability estimate for the solution of the corresponding Cauchy problem.

We consider two phaseless inverse problems for elliptic equation. The statements of these problems differ from have considered. Namely, instead of given information about modulus of scattering waves, we consider the information related to modulus of full fields, which consist of sums of incident and scattering fields. These full fields are the interference fields generated by point sources. We introduce a set of auxiliary point sources for solving the inverse problems and demonstrate that the corresponding data allow us to solve the inverse problems in a way similar to the case of measurements of scattering waves.

In this paper we discuss the unique determination of unknown spatial load $F(x)$ in the damped Euler-Bernoulli beam equation $\rho(x) u_{tt}+\mu u_{t}+(r(x)u_{xx})_{xx}=F(x)G(t)$ from final time measured output (displacement, $u_{T}(x):=u(x,T)$ or velocity, $\nu_{t,T}(x):=u_t(x,T)$). It is shown in [A. Hasanov Hasanoglu and V.G. Romanov, \emph{Introduction to Inverse Problems for Differential Equations}, Springer, New York, 2017] that the unique determination of $F(x)$ in the undamped wave equation $u_{tt}-(k(x)u_{x})_{x}=F(x)G(t)$ from final time output is not possible. This result is also valid for the undamped beam equation $\rho(x) u_{tt}+(r(x)u_{xx})_{xx}=F(x)G(t)$. We prove that in the presence of damping term $\mu u_{t}$, the spatial load can be uniquely determined by the final time output, in terms of the convergent Singular Value Expansion (SVE), as $F(x)=\sum_{n=1}^{\infty} u_{T,n}\psi_n(x)/\sigma_n$, under some acceptable conditions with respect to the final time $T>0$, the damping coefficient $\mu>0$ and the temporal load $G(t)>0$. As an alternative method we propose the Adjoint Problem Approach (APA) and derive an explicit gradient formula for the Fr\'{e}chet derivative of the Tikhonov functional $J(F)=\Vert u(\cdot,T;F)-u_T \Vert_{L^2(0,l)}^2$. Comparative analysis of numerical algorithms based on SVE and APA methods are provided for the harmonic loading $G(t)= \cos (\omega t)$, $\omega>0$, as a most common dynamic loading case. The results presented in this paper not only clearly demonstrate the key role of the damping term $\mu u_{t}$ the inverse problems arising in vibration and wave phenomena, but also allows us, firstly, to find admissible values of the final time $T>0$, at which a final time measured output can be extracted, and secondly, to reconstruct the unknown spatial load $F(x)$ in the damped Euler-Bernoulli beam equation from this measured output.

The conditions for the irradiation of 168Yb-enriched samples in reactors for obtaining sources to be used in brachytherapy are examined. The optimum irradiation conditions in the SM-3 high-flux reactor are determined. The computational methods are compared with the measurements.

The purpose of this article is to classify existing approaches to analyzing theoretical and methodological aspects of innovation development in modern economic systems. We also present a new approach based on existing ones that combines advantages, eliminates drawbacks, and offers means of analyzing innovation development in modern economic systems and that presents optimal models of innovation development in modern economic systems. The authors develop and approbate - based on the case of present-day Russia - proprietary methodologies for examining innovation development in modern economic systems. It involves the calculation of an index of innovation development that reflects current levels of innovation development in economic systems and possibilities and perspectives related to innovation development in economic systems in the near future. The authors classify approaches to the analysis of theoretical and methodological aspects of innovation development in modern economic systems as criteria on innovation development in economic systems. Within this classification, the authors distinguish between and conduct comparative analyses of the following three main approaches: plan-factual, ranking, and indexing, which involve making various theoretical assumptions on innovation development in modern economic systems and on the use of various methodologies. The authors present a new approach to the analysis of theoretical and methodological aspects of innovation development in modern economic systems that eliminate drawbacks of existing approaches and that present unique advantages (simple calculations and universal use). In turn, an optimal model of innovation development in modern economic systems is offered.

The glycolytic rate in neurons is low in order to allow glucose to be metabolized through the pentose-phosphate pathway (PPP), which regenerates NADPH to preserve the glutathione redox status and survival. This is controlled by 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), the pro-glycolytic enzyme that forms fructose-2,6-bisphosphate, a powerful allosteric activator of 6-phosphofructo-1-kinase. In neurons, PFKFB3 protein is physiologically inactive due to its proteasomal degradation. However, upon an excitotoxic stimuli, PFKFB3 becomes stabilized to activate glycolysis, thus hampering PPP mediated protection of redox status leading to neurodegeneration. Here, we show that selective inhibition of PFKFB3 activity by the small molecule AZ67 prevents the NADPH oxidation, redox stress and apoptotic cell death caused by the activation of glycolysis triggered upon excitotoxic and oxygen-glucose deprivation/reoxygenation models in mouse primary neurons. Furthermore, in vivo administration of AZ67 to mice significantly alleviated the motor discoordination and brain infarct injury in the middle carotid artery occlusion ischemia/reperfusion model. These results show that pharmacological inhibition of PFKFB3 is a suitable neuroprotective therapeutic strategy in excitotoxic-related disorders such as stroke., J.P.B. is funded by the MINECO (SAF2016-78114-R), CIBERFES (CB16/10/00282), H2020 European Commission (BatCure Grant 666918), Ayudas Fundación BBVA a Equipos de Investigación Científica en Biomedicina 2017 and Fundación Ramón Areces. A.A. is funded by H2020 European Commission (PANA grant 686009), Instituto de Salud Carlos III (PI15/00473; RD16/0019/0018) and Fundación Ramón Areces. J.P.B. and A.A. are in part funded by FEDER. This work was part of the “Escalera de Excelencia” program of the Junta de Castilla y León (CLU-2017-03) co-funded by the P.O. FEDER of Castilla y León 14–20.

The inverse problem of recovering the potential q(x) in the damped wave equation m ( x ) u t t + μ ( x ) u t = r ( x ) u x x + q ( x ) u , (x, t) ∈ Ω T ≔ (0, ℓ) × (0, T) subject to the boundary conditions u(0, t) = ν(t), u(ℓ, t) = 0, from the Neumann boundary measured output f(t) ≔ r(0)u x (0, t), t ∈ (0, T] is studied. The approach proposed in this paper allows us to derive behavior of the direct problem solution in the subdomains defined by characteristics of the wave equation and along the characteristic lines, as well. Based on these results, a local existence theorem and the stability estimate are proved. The compactness and Lipschitz continuity of the Dirichlet-to-Neumann operator are derived. Fréchet differentiability of the Tikhonov functional is proved and an explicit gradient formula is derived by means of an appropriate adjoint problem. It is proved that this gradient is Lipschitz continuous.

In this work, the experimental results of surface barrier discharge plasma products affection to winter rye seed germination at the initial stage of growth and seedling tolerance to low temperatures are shown. The treatment was carried out for 10, 60, and 180 s in the plane-parallel electrode system with sinusoidal voltage of 2.7 kV with frequency 4.4 kHz applied to the strip electrodes at a distance of 5 mm from each other. It is shown that the treatment has no effect on seed germinating ability. In 180 s exposure treatment mode the stimulation of 3-day seedling shoot and root system length occurs. The freeze tolerance response of two-stage cold hardened seedlings grown from treated seeds shows that both the exposure of seed and the freezing temperature affect on the formation of positive response.

The stabilization of the beams of large-sized multi-beam hybrid mirror antenna (MBHMA), the reflector profile of which is subject to distortion due to changing operational factors, is a complicated technical task. One of the ways to maintain energy efficiency of the satellite communications system in these circumstances is to adapt the amplitude-phase distribution of the clusters of the antenna array to random deformations of the reflector. By statistical modeling, the potentially achievable characteristics of the system are evaluated. Three variants of adaptation of cluster excitation were modeled: a) for fixed clusters, b) for adaptation of excitation, c) for adaptation of weights and position of clusters, d) for adaptation of weights and cluster configurations. For multivariate calculations, we use the simplified model of MBHMA that we have proposed. Comparison with calculations in Ticra Grasp environment confirmed the correctness of the model. Not only radiation patterns, but also focal spots on the antenna array we calculated to determine the rational composition of cluster elements and the vector of their excitation coefficients. Beams gain within the service area for reflector deformations were the subject of analysis. The studies showed that gain decrease can be reduced to 0.1 … 0.2 dB instead of 1.6 dB taking place without adaptation.

Cross-glued wood panels are used in various areas of construction. In recent years, such panels are widely used in multi-storey panel and multi-storey frame construction. The use of panels in multi-storey residential and public construction is based on such an important natural property of wood as dissipativity - the ability to absorb a wide range of dynamic effects, including seismic effects. The structural form of buildings in modern high-rise construction is based mainly on a steel or reinforced concrete frame. High-rise buildings on a frame made of wooden glued elements, with wooden outer and inner panels began to be introduced into the construction practice 15 years ago. To date, residential and public buildings made of wooden cross-glued panels have been built in many countries of Europe and in the USA, Canada, Australia. It can be expected that in high-rise construction, the share of residential and public buildings with the use of wooden glued structures will increase, and will stabilize over time in an objectively justified indicator. The demand for wooden high-rise construction will be determined, among other factors, by the seismicity of the construction areas.

The inverse problem of identifying the unknown spacewise dependent source F(x) in 1D wave equation is considered. Measured data are taken in the form g(t) := u(0; t). The relationship between that problem and Ground Penetrating Radar (GRR) data interpretation problem is shown. The non-iterative algorithm for reconstructing the unknown source F(x) is developed. The algorithm is based on the Fourier expansion of the source F(x) and the explicit representation of the direct problem solution via the function F(x). Then the minimization problem for discrete form of the Tikhonov functional is reduced to the linear algebraic system and solved numerically. Calculations show that the proposed algorithm allows to reconstruct the spacewise dependent source F(x) with enough accuracy for noise free and noisy data., 15 pages, 4 figures, 3 tables

High-frequency electron paramagnetic resonance (EPR), electron spin echo (ESE), electron-nuclear double resonance (ENDOR) and optically detected magnetic resonance (ODMR) were applied for the investigation of the electronic properties of ZnO colloidal quantum dots (QDs) which consist of a ZnO nanocrystal core and Zn(OH)2 shell. Shallow donors (SDs) in the form of interstitial atoms of lithium and sodium, as well as substituent of the aluminum have been identified and the spatial distribution of their electronic wave functions has been determined in the regime of quantum confinement. Hyperfine interactions as monitored by ENDOR quantitatively reveal the transition from semiconductor to molecular properties upon reduction of the size of the nanoparticles. We studied the process of charge separation in the quantum dot when excited by UV light resulting in the formation of shallow donors and deep acceptors in the paramagnetic state, which recombine when heated, accompanied by thermoluminescence go back again in the non-paramagnetic state. It was shown that in all studied quantum dots deep acceptors are present positioned near the interface and including one sodium atom. ODMR techniques, which is based on EPR detection via photoluminescence or via tunneling afterglow that can be observed after preliminary X-ray or UV irradiation proved to be very useful to study colloidal ZnO NCs. The higher sensitivity of ODMR via afterglow allowed characterization of ZnO QDs dispersed in transparent media, which is an important advantage, since these systems are more relevant for a number of practical applications. A direct evidence of Co (Mn) interaction with SD in the core and hyperfine coupling with 1H in the shell of QDs has been demonstrated in Mn (Co)-doped ZnO QDs, which are promising classes of diluted magnetic semiconductors.

This article is devoted to research of the categorical color perception in different parts of the visual field as a part of the general problem of linguistic determination of color perception. The main hypothesis is that the change in visual angle at the presentation of color stimuli influences the categorical effects of color perception. The study included 60 children. The basic experimental procedure was carried out in computer program based on the visual search paradigm. We compared time of the between- and within-category color distinction at three conditions of the visual angle in three different color diapasons. The results showed that the categorical effects of color perception occur when the stimuli locate in the field of clear vision (5°). Categorical effects disappeared when value of retinal declination was 15 or 25°. The results show decrease of total reaction time with increasing values of the visual angle, i.e. the speed of reaction was faster when color stimuli appeared in peripheral vision. Additional we have studied the presence of categorical effects in border and focal colors. The study showed that categorical effects occur only at border colors in the field of clear vision. We have seen no categorical effect at the focal colors regardless of visual angle.

The work considers the possibility of using metamaterials to design of low-gain antennas with improved parameters of antenna pattern. It is shown that additional elements of the antenna, made of metamaterial, can be considered as antenna array of parasitic emitters, forming antenna pattern of the required shape. It is shown that the use of metamaterial inserts allows to optimize irradiators for reflector and lens antennas.

In this work we have performed an analysis of electrostriction mechanism of optical to acoustical energy conversion on the interface of two materials with low optical absorption. We compared this method of conversion with widely used thermal conversion based on thin metal film. It was shown, that the contribution of electrostriction mechanism is significantly lower in case of homogeneous medium. We demonstrated the possibility to amplify the generated acoustic signal by excitation of the guided modes, which energy is localized in a thin (of about 200-400 nm thickness) dielectric layer. Due to high electromagnetic field energy concentration in the structure, local values of intensity increase by more than two order of magnitude in comparison to intensity of incident light, that also allows to increase the amplitude of the pressure correspondingly. Thus, in the project we propose the novel layered dielectric structures, in which electrostriction effect occurs due to excitation of the guided modes.