bluuebunny/crossref_metadata_2025_split huggingface dataset:
Joint User Pairing and Subcarrier Allocation for NOMA-based Hybrid Power Line and Visible Light Communication Systems
Authors: Teng Deyang , Zheng Yanxi , Luo Man , Luo Yiqiao , Jinyuan Wu 
Published: December 2020

Abstract
With the rapid growth of the number of mobile communication users, the radio frequency bands occupied by traditional radio frequency (RF) communication are becoming more and more crowded, and visible light communication (VLC) based on light emitting diode (LED) has become a powerful candidate. However, visible light cannot be used directly as an information source, and power line communication (PLC) is needed to provide data to the VLC transmitter. In a hybrid power line and visible light communication (HPV) system, the PLC can transmit data to the VLC transmitter. In order to improve spectrum utilization, we introduce non-orthogonal multiple access (NOMA) technology, but allocating all users to a resource block will result in higher computational complexity and decoding delay. This paper proposes a joint user pairing and subcarrier allocation algorithm based on fairness (IGA-JUPSA). While ensuring the performance of the system, the algorithm can also reduce the complexity of calculation and improve user satisfaction. The simulation results show that the proposed IGA-JUPSA scheme can reduce the computational complexity while ensuring the performance of the HPV system, and can also take into account the fairness of the HPV system and user satisfaction.
Research on knowledge graph model of diversified online resources and personalized recommendation
Authors: Ni Zhenglin , Ni Fangwei 
Published: December 2020

AbstractThis paper proposes an improved knowledge graph model to match the distinctiveness in the education field, considering the lack of robustness and resource diversity in the existing research on knowledge graphs in the education field. A recommendation algorithm based on personalized features is given on the new knowledge graph model to improve recall and precision. Finally, we verify the robustness and expression ability in course resource diversity. The results show that the recall rate of curriculum resources is improved to 0.95-0.96, personalized satisfaction is up to 0.96 and the difference of recommended resources is up to 0.9.
Human action recognition based on Kinect
Authors: An Jiahui , Cheng Xinrong , Wang Qing , Chen Hong , Li Jiayue , Li Shiji 
Published: December 2020

Abstract
With the emergence of Kinect, many research results have emerged in human action recognition based on skeleton information, which has promoted the development of human-computer interaction. In this paper, from the skeleton data obtained by Kinect, static features and dynamic features are extracted, and the two are merged; SVM classifier is used for action recognition. It is verified on the MSR Daily Activity 3D data set, and the experimental results show that the method in this paper improves the accuracy of action recognition.
Research on Intelligent Control of Photovoltaic Power Generation Fluctuation Based on Linear Active Disturbance Rejection
Authors: Wenxuan Gao 
Published: December 2020

Abstract
Nowadays, the output power of photovoltaic power generation fluctuates greatly, which endangers the safe and stable operation of the power grid. Therefore, a method for eliminating photovoltaic power generation volatility based on linear active disturbance rejection control is proposed in the paper. Moreover, through establishing the “anti-disturbance paradigm” model of the photovoltaic power generation system, the frequency scale transformation is introduced to design the linear expansion state observer is. Meanwhile, the linear expansion state observer output is converted too. Besides, proportional calculus controller is used for control, and parameter tuning is achieved through linear auto-disturbance rejection control technology to obtain optimal parameters, thereby completing the elimination of photovoltaic power generation volatility. The simulation experiment results show that when LADRC control is added, the phase A voltage fluctuation is small and the output current is relatively stable, which can effectively reduce the active power output by the photovoltaic power generation unit and improve the execution efficiency.
The study of the influence of interstellar extinction laws on the parameters of photometric system using astrophysical observations taken at EAO
Authors: Kuandykova D M , Andreev A O , Nefedyev Y A , Demina N Y , Borovskih V S 
Published: December 2020

Abstract
In this work, connections between UBV (PSC UBV) photometric systems for various laws of interstellar extinction are calculated on the basis of digital database on astrophysical observations of Engelhardt astronomical observatory (EAO) and using the specialized software package for analyzing brightness characteristics. The following results are obtained: 1) when using various laws of interstellar extinction, the value of difference in the position of reaction curves is proportional to the difference between UBV dependencies and color indices; 2) the positions of reaction curves and connection curves between UBV and color indices are influenced by spectral characteristics of the filters used in observations; 3) the same applies to the transformation of stellar magnitudes from one standard system to another, as response curves as a rule significantly differ; 4) another conclusion is that for any separate model of interstellar extinction the differences in color between photometric systems do not depend on spectral and luminosity classes.
A kinetic model for equilibrium binding of intercalation dye with DNA during its amplification
Authors: Fedorov A A , Murav’ev A V 
Published: December 2020

Abstract
Recently, a number of models of polymerase chain reaction (PCR) have been proposed. In such models, the kinetics of a reaction product and a fluorescence reporter used are usually identified. An intercalation dye is one of the two ways for “real time” detection of reaction product accumulation. In this work a PCR model is proposed, with using of intercalation dye to obtain a PCR curve. The concentration of bound intercalation dye was calculated at the end of each PCR cycle. This calculation is based on an equilibrium equation for intercalation dye binding with DNA. An analysis of simulation results demonstrates a significant difference between the accumulation kinetics of the reaction product and the fluorescent signal of the bound intercalation dye.
Visualization of the intracellular structures of bacteria using expansion microscopy
Authors: Rumyantseva N A , Vedyaykin A D , Vishnyakov I E , Khodorkovskii M A 
Published: December 2020

Abstract
Expansion microscopy (ExM) is a powerful tool which allows to visualize intracellular structures with increased resolution due to physical widening of the sample. ExM resolution is comparable to that of some super-resolution microscopy techniques, but it does not require the use of complex and expensive optical equipment, thereby providing improvement in resolution even if relatively simple microscopes are used. In this work we successfully utilized ExM to visualize structures formed by FtsZ protein and DNA in Escherichia coli cells. The results of the work demonstrate that structures formed by both FtsZ and DNA are highly sensitive to the sample preparation procedure which should be optimized in each case of the ExM use.
Efficiency enhancement of THz radiation from an electron bunch in a waveguide due to low-frequency stabilization
Authors: Oparina Yu S , Bratman V L , Lurie Yu , Savilov A V 
Published: December 2020

Abstract
Simultaneous generation of pulses of high-frequency Super-Radiance and low-frequency Coherent Spontaneous Radiation from an ultra-relativistic electron bunch moving in a waveguide placed in a spatially periodic and / or uniform longitudinal magnetic field is studied. The low-frequency radiation can weaken expansion of the bunch and decrease a velocity spread. This significantly improves electron micro-bunching and increases energy of high-frequency pulses. Such effect makes possible fairly efficient high-frequency cyclotron radiation of the bunch near an autoresonance regime, when the wave phase velocity is very close to speed of light.
Synthesis of composite single crystal structures on the basis of iron borate for fundamental studies and practical applications
Authors: Mogilenec Yu , Seleznyova K , Seleznev K. , Strugatsky M , Yagupov S 
Published: December 2020

Abstract
Composite single crystal structures based on iron borate FeBO3, namely diamagnetically diluted iron-gallium Fe1-xGaxBO3 and iron-aluminium Fe1-xAlxBO3 borates with low x-values, as well as doped GaBO3:Ni single crystals with Ni 0.1-0.01 mass %, have been synthesized using modified flux growth technique. Two technological modes that allowed improving the quality of the samples have been developed: crystallization in (1) open and (2) closed crucibles. Thin magnetic film of iron borate on a diamagnetic gallium borate substrate have been synthesized by liquid-phase epitaxy route.
Efficient approach to calculating radial distribution function in bcc Fe lattice
Authors: Mistryukova Lukiya A. , Kryuchkov Nikita P. , Aliev Ismail N. , Yurchenko Stanislav O. 
Published: December 2020

Abstract
Many properties of condensed matter systems can be described by means of pair correlation functions that makes them an important structural characteristic. The shortest-graph interpolation method allows us to calculate pair correlation functions of classical crystals with pairwise interactions between particles. However, there is still no just so simple and practical approach to predict correlation functions in crystals with many-body interactions that are ubiquitous in nature. In this work, a simple modification of the interpolation method is suggested allowing to describe pair correlations bcc Fe lattice, considered as a classical crystal with many-body interactions of embedded atom model type. It is shown that the radial distribution function of the crystal can be calculated with high accuracy if mean square displacements are known. The obtained results would be useful in various fields of condensed matter physics, materials science, and crystallography.
The initial-boundary problem for the system of 1D equations of non-Newtonian hemodynamics
Authors: Krivovichev Gerasim V 
Published: December 2020

AbstractThe paper is devoted to the analytical solution of the problem for 1D hemodynamical equations with periodic boundary conditions. The method of the solution is based on the asymptotic expansions on the small parameter and Fourier method. The attention is focused only on the first-order terms in the expansion. The solution, obtained for the particular case of initial conditions, is used for the comparison of rheological models of blood. It is demonstrated that the strongest damping takes place for the Power Law non-Newtonian model.
Interaction of a soliton wave with nanopores in stoichiometry crystals A3B
Authors: Zakharov P V , Starostenkov M D , Lucenko I S , Kochkin A S 
Published: December 2020

Abstract
Solitons are essentially nonlinear and stable objects in various environments. In this work, the molecular dynamics method is used to study the propagation of solitary waves in a discrete medium in the form of an A3B stoichiometry crystal and their interaction with nanopores. The model under consideration was a Pt 3Al crystal, the atoms of which interacted through the potential obtained by the immersed atom method. Such waves can propagate to hundreds of nanometers across the crystal. We have studied the passage of waves through a cell containing nanopores of various diameters. The mechanisms of energy dissipation in the process under consideration are shown. The distance after the obstacle at which the wave front is restored is estimated. The energy characteristics of a solitary wave after interaction with a topological defect in the form of a cylindrical nanopore are calculated. The results obtained can be useful both from a fundamental point of view in studying the properties of solitons, and from practical for non-destructive testing methods.
Dzyaloshinskii-Moriya interaction constant in iron-gallium borate single crystals
Authors: Mogilenec Yu , Seleznyova K , Yagupov S , Strugatsky M , Kliava J 
Published: December 2020

Abstract
The Dzyaloshinskii-Moriya interaction constant for iron-gallium borate FexGa1-xBO3 single crystals has been calculated on the basis of considering antisymmetric exchange in a pair of nearest-neighbouring magnetic ions. Both numerical and analytical calculations predict a square-law dependence of the Dzyaloshinskii-Moriya constant on the contents of magnetic ions, x, in the crystals.
The inverse problem of the oscillation of a rod with a variable cross section
Authors: Utyashev I M , Yulmuhametov A A , Aitbaeva A A 
Published: December 2020

Abstract
Variable cross-section rods are used in many parts and mechanisms. For example, conical rods are widely used in percussion mechanisms. The strength of such parts directly depends on the natural frequencies of vibrations. Oscillations and vibration are also used in diagnostics, for example in acoustic diagnostics of defects. The paper presents a method that allows numerically finding a variable cross section of an elastic rod from the natural frequencies of longitudinal vibrations. It is assumed that the cross-sectional area varies along the axis and is described by an exponential function of a polynomial of degree n. The boundary condition on the left end is hard, on the right-elastic. It is shown that to determine n unknown coefficients of the cross section function, n natural frequencies are required.
The growth of hexagonal and cubic GaN on a nano-patterned Si(100) substrate
Authors: Bessolov V , Konenkova E , Konenkov S , Rodin S , Seredova N 
Published: December 2020

Abstract
The results of studies of semipolar GaN(10-12) layers synthesized on a nano-patterned Si(100) substrate are presented. It is shown that in the method metalorganic vapor phase epitaxy, the use of a nanorelief consisting of V-shape groove with inclined faces close to the Si(111) plane can lead to the formation of regions of cubic gallium nitride in the nano-groove. Model of the origin of the cubic phase are based on the formation of AlN nuclei in (0001) and (10-10) nano-groove and the conjugation of the AlN(10-10) and c-GaN planes by the “magic mismatch” mechanism.
The study of heat-resistant fibers obtained from a melt of thermoplastic crystallizable polyimide
Authors: Vaganov G V , Ivan’kova E M , Didenko A L , Popova E N , Elokhovsky V Yu , Yudin V E 
Published: December 2020

Abstract
The homologous series of thermoplastic polyetherimide based on resorcinol dianhydride R (1,3-bis-(3,3’,4,4’-dicarboxyphenoxy)benzene) and tetranuclear diamine BAPB (4,4’-bis(4”-aminophenoxy) biphenyl) (R-BAPB) were synthesized in powder form. Fibers were obtained by melt spinning of this polyimide. It was analyzed, how changes in the molecular weight of polyimide can affect the ability to form fibers through the melt. The influence of the degree of orientation high-temperature drawing on the thermal mechanical properties and the change in the morphology of the polymer was studied. An increase in draw ration (DR) from 1 to 4 led to a substantial increase in tensile strength and Young’s modulus of polyimide fibers.
Strain determination in heterostructures by TEM in selected area electron diffraction mode
Authors: Snigirev L A , Kirilenko D A , Bert N A 
Published: December 2020

Abstract
The technique for determination of strain and elemental composition distribution across the graded layer in heterostructures by means of selected area electron diffraction in transmission electron microscope (TEM) is proposed. The approach accounts for the modification in the residual elastic strain due to sample thinning during TEM specimen preparation. The technique is approved using In0,7Ga0,3As/InxAl1-xAs/GaAs(001) and Al0,75Ga0,25N/AlN/Al2O3
heterostructures, and the results are in a good agreement with those obtained by alternative ways.
Chemometric analysis of Raman spectra of tissues of the teeth with periapical periodontitis
Authors: Timchenko E V , Timchenko P E , Zybin M A , Cherny-Tkach K B , Frolov O O , Dolgushov G G 
Published: December 2020

Abstract
The Raman spectra of dental tissues with periapical periodontitis have been analyzed. Chemometric analysis of the Raman spectra of hard dental tissues of healthy patients and the patients with periapical periodontitis has been carried out. The main spectral features of dental tissues with periapical periodontitis have been identified, which will further allow developing new methods of early detection of periapical periodontitis.
Investigation of characteristics of GaAs/AlGaAs p-i-n connecting tunnel diodes
Authors: Kontrosh E V , Lebedev V V , Klimko G V , Kalinovskii V S , Andreev V M 
Published: December 2020

Abstract
Current-voltage and capacitance-voltage characteristics of tunnel diode structures with GaAs-n++/i-GaAs/i-Al0,2Ga0,8As/Al0,2Ga0,8As-p++ active region and i-layer thicknesses of 7.5 nm and 10 nm and epitaxial growth temperature of 450 °C and 500 °C have been studied. The tunnel diode structures grown by the molecular beam epitaxy technique are intended for application as connecting elements in multijunction photovoltaic converters of high-power monochromatic optical radiation. According to the results obtained, the peak tunnel current density of up to 200 A/cm2 is achieved. Forward current-voltage and capacitance-voltage characteristics of tunnel p-i-n diode structures were measured at room temperature. The capacitance-voltage characteristics of the tunnel diodes being tested were obtained experimentally with the frequency dependence of S-parameters simulated within 10-1000 MHz at bias voltages of 0.4–1 V.
Study of a gas breakdown in a focused beam of terahertz radiation at the NovoFEL user station
Authors: Vodopyanov A , Kubarev V , Sidorov A , Shevchenko O , Gorbachev Y , Barmashova T 
Published: December 2020

Abstract
The paper describes the features of the design of an experimental bench for studying a discharge in a highly inhomogeneous gas stream, supported by focused radiation in the terahertz range. The setup was created at the user station of the Novosibirsk free-electron laser. The optical scheme that allows one to achieve electric field strength in the wave of up to 1 MV/cm is described. The results of the first experiments on the study of a breakdown in a focused radiation beam with a frequency of 2.3 THz are described.
Coatings with controlled degree of hydrophobicity based on powder polymer coatings
Authors: Vaganov G V , Vaganov V V , Radchenko I L , Ilyina I A 
Published: December 2020

Abstract
The coatings with controlled degree of hydrophobicity based on epoxy-polyester powder compositions on an aluminum surface were obtained. The study of changes in surface properties (contact angle and surface energy) and the physico-mechanical properties of the coatings, depending on the concentration of the fluorine additive, was carried out. Modification of the polymer powder composition with a fluorine additive leads to a sharp increase in the degree of hydrophobicity from hydrophobic to the formation of a superhydrophobic coating) and the saving of high mechanical properties of the coating obtained on them.
Relaxation transitions in UHMWPE near-surface layers as revealed by the thermoluminescence method
Authors: Myasnikova L P , Marikhin V A , Gladkov A K , Solov’eva O Yu , Radovanova E I , Boiko Yu M , Egorov E M 
Published: December 2020

Abstract
Aiming at finding the proper UHMWPE reactor powders convenient for solvent-free technology producing high-strength fibers, the comparative study of the near-surface layers of the commercial and lab-scale UHMWPE reactor powders was carried out with the help of the thermoluminiscence method. The difference in the powder glow curves and changes in them after subjecting the powders to various processing (compaction and sintering) were observed. Decomposition of the curves was carried out using Fityk program. The energy activation of the electron trap erosion, and the relative content of the shallow and deep traps in the samples investigated were calculated. The association of these observations with the mechanical propeties of the end sintered oriented product is discussed.
Powerful ultraviolet laser pulse impact on polished metals and semiconductors
Authors: Khomich Yu V , Malinskiy T V , Mikolutskiy S I , Rogalin V E , Yamshchikov V A , Kaplunov I A , Ivanova A I 
Published: December 2020

Abstract
Laser treatment for samples of copper, its alloys and gold was carried out with a UV pulse of nanosecond duration. After irradiation at subthreshold values of the energy density (E ∼ 0.2 - 0.8 J/cm2) the noticeable changes in the surface layer were revealed. These are traces of thermoplastic deformation resulting from laser exposure. They appear as uneven rise of the irradiated sample surface area up to 1 μm. The effect is cumulative, because the height of the uplifts increases with increasing number of impact pulses. In addition, the characteristic features of high-temperature plastic deformation were observed in the form of crystallographic slip and grain-boundary slippage. At E ∼ 1 J/cm2 or more the optical breakdown occurred with the formation of a crater on the metal surface, that precludes the detection of described effects. The mechanical impulse of a laser plasma, when exposed to a metal surface, prevents the thermomechanical expansion of the material, and therefore, similar effects have not been previously observed. On the surface of materials with a significantly larger elastic limit (single crystals of germanium and silicon, a tungsten carbide) this phenomenon was not observed, because the generated thermomechanical stresses were insufficient to create conditions of plastic deformation.
Contactless method for online control tension of radio-reflective mesh surface of large-sized folding mirror antennas
Authors: Sayapin S N 
Published: December 2020

Abstract
A new contactless method for online control tension of a radio-reflective mesh surface of a large-sized folding mirror antenna is presented. The method is based on revealing the correlation between Moire patterns and net-shaped curtain uniformity and tension. The advantages of the method are presented. Its main advantage lies in the fact that it is possible to set the net-shaped curtain on the folding skeleton of an antenna reflector in the online mode. The presented method is universal and can be used not only to manufacture antenna reflectors with the working surface in the form of a net-shaped curtain but also in any other structures in which the checked element is a net, regardless of the material of which it is made. A way to apply the method is presented.
Mechanical analogue in hydroelasticity
Authors: Pozhalostin A.A. , Goncharov D.A. 
Published: December 2020

Abstract
Lineal oscillation modelling of various mechanical systems is a quite common way of representation and simplification of rather complicated systems. One of the most impressions and exciting appearance of lineal oscillation modelling was made by RAS academician Konstantin Sergeevich Kolesnikov in a problem of liquid-structure interactive and the influence of that interactive on vehicle dynamics, especially in a case of rocket motion. K.S. Kolesnikov considered mathematical pendulum according to the problem of the small oscillations of an ideal liquid in a rigid cylindrical shell.