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6th International Conference on Numerical Analysis and Applications (NAA)

作者： Yaparova, Natalia M. Natl Res Univ South Ural State Univ Dept Computat Math & High Performance Comp Pr Lenin 76 Chelyabinsk 454080 Russia

ISBN: (纸本)9783319570990;9783319570983

We consider an inverse boundary values problem for parabolic PDE with unknown initial conditions. In this problem both Dirichlet and Neumann boundary conditions are given on a part of the boundary and it is required to determine the corresponding function on the remaining part of the boundary. To solve this problem, the numerical method based on finite difference schemes and regularization technique is proposed. The computing scheme involves solving the equation for each spatial step that allows to obtain the numerical solution in internal points of the domain and on the boundary. We prove a conditional stability of the method. The reliability and the efficiency of the method were confirmed by computational results.

关键词： Heat conduction problem Inverse problem Regularization method computational scheme Conditional stability

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Prediction of microwave absorption properties of tetrapod-needle zinc oxide whisker radar absorbing material without prior knowledge

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JOURNAL OF APPLIED PHYSICS 2017年第2期122卷 025112-025112页

作者： Zhao, Yu-Chen Wang, Jie Liu, Jiang-Fan Song, Zhong-Guo Xi, Xiao-Li Xian Univ Technol Shaanxi Key Lab Complex Syst Control & Intelligen Xian 710048 Peoples R China Naval Univ Engn PLA Wuhan 430033 Peoples R China

The radar absorbing material (RAM) containing a tetrapod-needle zinc oxide whisker (T-ZnOw) has been proved to have good efficiency of microwave absorption. However, the available theoretical models, which are intended to predict the microwave absorbing properties of such an interesting composite, still cannot work well without some prior knowledge, like the measured effective electromagnetic parameters of the prepared T-ZnOw composite. Hence, we propose a novel predictive method here to calculate the reflectivity of T-ZnOw RAM without prior knowledge. In this method, the absorbing ability of this kind of material is divided into three main aspects: the unstructured background, the conductive network, and the nanostructured particle. Then, the attenuation properties of these three parts are represented, respectively, by three different approaches: the equivalent spherical particle and the static strong fluctuation theory, the equivalent circuit model obtained from the complex impedance spectra technology, and the combination of four different microscopic electromagnetic responses. The operational calculation scheme can be obtained by integrating these three absorption effects into the existing theoretical attenuation model. The reasonable agreement between the theoretical and experimental data of a T-ZnON/SiO2 composite in the range of 8-14 GHz shows that the proposed scheme can predict the microwave absorption properties of the T-ZnOw RAM. Furthermore, a detailed analysis of these three mechanisms indicates that, on the one hand, the background plays a dominant role in determining the real part of the effective permittivity of the T-ZnOw composite while the network and the particle are the decisive factors of its material loss;on the other hand, an zero-phase impedance, i.e., a pure resistance, with appropriate resonance characteristic might be a rational physical description of the attenuation property of the conductive network, but it is difficult to realize such

关键词： attenuation characteristic fluctuation theory MATERIAL LOSS effective permittivity computational scheme absorption effect microwave absorption Radar absorbing materials series resonance circuit FAM103A1 gene zinc oxide whisker CCDC26 gene

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DFT, L(S)DA, LDA plus U, LDA plus DMFT, .... , Whether We do Approach to a Proper Description of Optical Response for Strongly Correlated Systems?

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OPTICS AND SPECTROSCOPY 2016年第4期121卷 467-477页

作者： Moskvin, A. S. Ural Fed Univ Dept Theoret Phys Ekaterinburg 620083 Russia

I present a critical overview of so-called "ab initio" DFT (density fuctional theory) based calculation schemes for the description of the electronic structure, energy spectrum, and optical response for strongly correlated 3d oxides, in particular, crystal-field and charge transfer transitions as compared with an "old" cluster model that does generalize crystal-field and ligand-field theory. As a most instructive illustration of validity of numerous calculation techniques I address the prototypical 3d insulator NiO predicted to be a metal in frames of a standard LDA (local density approximation) band theory.

关键词： Charge transfer transition Cluster model Ligand field theory computational scheme SOS Calls laser Doppler anemometry Left-sided displacement of abomasum

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DRAGON5 and DONJON5, the contribution of Ecole Polytechnique de Montreal to the SALOME platform

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ANNALS OF NUCLEAR ENERGY 2016年第Part1期87卷 12-20页

作者： Hebert, Alain Ecole Polytech Inst Genie Nucl Montreal PQ H3C 3A7 Canada

The DRAGON lattice code and DONJON full core simulation code are in active development since 1990. A lattice code is used to solve the neutron/photon transport equation using a deterministic approach over a domain corresponding to a subpart or over a complete 2D or 3D nuclear reactor. A full core simulation code includes steady state and transient neutron flux solution capabilities together with reactor operation, micro depletion, and simplified thermal-hydraulics models. The DRAGON and DONJON codes are designed around a scripting language, known as CLE-2000, to automate the flow of information used in computational schemes. DRAGON5 and DONJON5 are the latest version of these codes and features characteristics that are required to design advanced nuclear reactors. First, a new kernel, named GANLIB5, was implemented entirely in ANSI C to facilitate the coupling of the code in multi-physics environments and to permit the embedding in control systems. Second, we added new geometric capabilities to permit the representation of complex geometries that are typical of advanced applications. The first release of DRAGON5 and DONJONS was available in October 2013. Subsequent releases are permitting couplings with the geometry module (Geometry) and supervisor module (YACS) of the SALOME platform. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Lattice code Neutron transport Deterministic solution computational scheme Computer-aided design

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The Ishlinskii oscillator model in the Keldysh shimmy problem

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PMM JOURNAL OF APPLIED MATHEMATICS AND MECHANICS 2016年第2期80卷 127-132页

作者： Plakhtienko, N. P. Shifrin, B. M. Natl Aviat Univ Ukraine Kirovograd Flight Acad Kirovograd Ukraine

***. Ishlinskii's idea concerning the correspondence between a 'vibrating system at the threshold of stability and a hypothetical one-degree-of-freedom linear system' is used. For the case of linear shimmy, procedures are proposed for constructing an oscillator model, checking its correspondence to a prescribed system, and using it to find the vibration frequencies and amplitudes. Within the framework of M.V. Keldysh's most simple calculation scheme, the shimmy of a towed, pliant pneumatic tyre is examined. The obtained laws of turning of the towing gear are compared with the results of numerical integration of the initial equations of motion. It is established that the oscillator model fits the Keldysh system adequately, at least if the length of the towing gear is no smaller than the radius of the pneumatic wheel. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： shimmy vibrating system Oscillator model Vibrational frequencies Amplitude Numerical integration Equations of motion Correspondence computational scheme Trailers Linear system

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A New Discretization Model to Include the Effect of Spatial Variability in the Reliability Analysis of Earth Slopes 3

A New Discretization Model to Include the Effect of Spatial ...

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Geo-Chicago Conference - Sustainability, Energy, and the Environment (Geo-Chicago)

作者： Metya, Subhadeep Bhattacharya, Gautam Chowdhury, Robin IIEST Dept Civil Engn Sibpur India Univ Wollongong Fac Engn Wollongong NSW Australia

ISBN: (数字)9780784480144

ISBN: (纸本)9780784480144

In the reliability analysis of earth slopes considering spatial variability of soil, the few models of discretization of random fields into finite random variables, available in the literature, have certain shortcomings. This paper presents a newly developed discretization model which is free from most of the shortcomings of the existing models. The developed discretization model has been incorporated in a computational scheme for slope reliability analysis based on the first order reliability method (FORM) in conjunction with the Spencer method of slices valid for limit equilibrium analysis of general slip surfaces. To elucidate the entire computational procedure as well as to examine the efficacy of the new discretization model, the safety of the Cannon Dam, USA, has been re-analysed. The results of reliability analyses have revealed that the proposed model yields the lowest value of the reliability index among all the models used in the analysis. Using the proposed model, a parametric study on the variations of the reliability index with the variations of magnitudes of the scales of fluctuation has also been carried out and reported.

关键词： Reliability analysis reliability index Discretization Spencer Technique topsoil Earth computational scheme

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Method for Temperature Measuring in the Rod with Heat Source Under Uncertain Initial Temperature 2

Method for Temperature Measuring in the Rod with Heat Source...

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2nd International Conference on Industrial Engineering, Applications and Manufacturing (ICIEAM)

作者： Yaparova, N. South Ural State Univ Chelyabinsk Russia

ISBN: (纸本)9781509013227

In this contribution, the problem of linear heating a object with unknown initial temperature by external thermal point source is considered. The object has an internal heat source. External terminal source is located on part of the boundary and we made the indirect dynamic measurements on the same part of the boundary. We propose a method for calculating temperature inside the body. This method is based on the measurement results under condition when the initial temperature of the object cannot be measured. The computing scheme of the method is based on using finite-difference schemes and discrete regularization method. We prove the conditional stability of the method and estimate the temperature errors via accuracy of the boundary measurements. The theoretical error estimates and computational results confirm sufficient efficiency and reliability of the proposed computational scheme.

关键词： dynamic measurements non-destructive testing method heat conduction inverse problem regularization method numerical method computational scheme

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New calculation schemes based on the large-particle method for modeling gas-dynamic problems

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DOKLADY PHYSICS 2015年第12期60卷 555-558页

作者： Grishin, Yu. A. Bakulin, V. N. Bauman State Tech Univ Moscow 107005 Russia Russian Acad Sci Inst Appl Mech Moscow 117312 Russia

In developing the numerical large-particle method, new calculation schemes providing for analytical determination of the parameters using the ambiguity principle and the transition to the second order of accuracy in time and space are presented. Furthermore, the change in the density at the Eulerian stage of the method is taken into account. As a result, the stability of the computing procedure of complex flows with separations and free jets is provided at the values of the difference Courant number close to unity. This circumstance makes it possible to reduce considerably the time of calculations and to increase their accuracy.

关键词： scheme free jets computational scheme Modeling

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Calculation of electronic coupling matrix elements in 4,4'-bis(9-carbazolyl)-biphenyl amorphous material

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HIGH ENERGY CHEMISTRY 2015年第3期49卷 173-176页

作者： Odinokov, A. V. Bagaturyants, A. A. Russian Acad Sci Photochem Ctr Moscow 119421 Russia Natl Res Nucl Univ MEPhI Moscow 115409 Russia

The electronic coupling matrix element responsible for positive charge carrier (hole) transport has been calculated for a variety of 4,4'-bis(9-carbazolyl)-biphenyl dimers corresponding to a disordered solid matrix. A procedure applying the computational scheme to a real system (organic molecules with a large molecular mass) is proposed. The consistency of the results with the existing model concept of hopping conductivity in organic semiconductors is discussed.

关键词： amorphous materials Organic Semiconductors Hopping(conductivity) Molecular weights electronic coupling computational scheme Matrix Element

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Efficient Analytical Calculation of the Plane Wave Coupling to Uniform Transmission Lines With Arbitrary Load Resistances in Time Domain

Efficient Analytical Calculation of the Plane Wave Coupling ...

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Joint IEEE International Symposium on Electromagnetic Compatibility (EMC) and EMC Europe

作者： Magdowski, Mathias Vick, Ralf Otto Von Guericke Univ Magdeburg Germany

ISBN: (纸本)9781479966165

An efficient calculation scheme for the plane wave coupling to a lossless and uniform transmission line in time domain is presented. The method is based on closed-form formulas and a finite sum. It is applicable for a single-wire transmission line above a perfectly conducting ground plane as well as for a double-wire line in free space. The line can be terminated with arbitrary linear load resistances. The exciting plane wave can be described by any time function that must be integrable. In comparison with a solution in the frequency domain and a subsequent inverse Fourier transform, the presented method is much faster, more exact and very comprehensible,

关键词： Transmission Lines TIME-DOMAIN Load Resistance computational scheme plane Platanus hybrida Planing Frequency-domain analysis waves Lossless Power cables Ground plane Arbitrary Uniform Uniforms

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