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Eigenvalue Analysis of Thin Plate with Complicated Shapes By a Novel infinite Element Method

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Computer Modeling in Engineering & Sciences 2019年第8期120卷 273-292页

作者： Deshin Liu Yuwei Chen Department of Mechanical Engineering and Advanced Institute of Manufacturing with High-Tech Innovations National Chung-Cheng UniversityMinhsiungChiayi 62102Taiwan

A novel infinite element method(IEM)is presented for solving plate vibration problems in this paper.In the proposed IEM,the substructure domain is partitioned into multiple layers of geometrically similar finite elements which use only the data of the boundary nodes.A convergence criterion based on the trace of the mass matrix is used to determine the number of layers in the IE model partitioning process.Furthermore,in implementing the Craig-Bampton(CB)reduction method,the inversion of the global stiffness matrix is calculated using only the stiffness matrix of the first element layer.The validity and performance of the proposed method are investigated by means of four illustrative problems.The first example considers the case of a simple clamped rectangular plate.It is observed that the IEM results are consistent with the theoretical results for first six natural frequencies.The second example considers the frequency response of a clamped rectangular plate with a crack.The main feature of IEM is that a very fine and good quality virtual mesh can be created around the crack tip.The third and fourth examples consider the natural frequency of a multiple point supported plate and a perforated plate,respectively.The results are obtained just need to adjust the reference point or boundary nodes.The parametric analyses for various geometric profiles are easy to be conducted using these numerical techniques.In general,the results presented in this study have shown that the proposed method provides a direct,convenient and accurate tool for eigenvalue analysis of thin plate structure with complicated shapes.

关键词： infinite element method Craig-Bampton method plate vibration eigenvalue problem

Broadband infinite-Q plasmons enable intense Smith–Purcell radiation

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Photonics Research 2023年第11期11卷 1945-1958页

作者： ZI-WEN ZHANG CHAO-HAI DU YU-LU LEI JUAN-FENG ZHU PU-KUN LIU Center for Carbon-based Electronics School of ElectronicsPeking UniversityBeijing 100871China State Key Laboratory of Advanced Optical Communication Systems and Networks School of ElectronicsPeking UniversityBeijing 100871China Science Mathematics and Technology(SMT)Singapore University of Technology and DesignSingapore 487372Singapore

With the rapid development of nanophotonics for enhancing free-electron radiation,bound states in the continuum(BICs)have emerged as a promising approach for emitting intense Smith–Purcell radiation(SPR)with enhanced intensity.However,current BIC-based methods are limited to single-frequency operation,thereby restricting their applications requiring spectral and angular tunability,such as particle detectors and light sources.To overcome this limitation,this work proposes an approach for constructing plasmonic BICs over a broad spectral range in symmetry-broken systems.By leveraging the high-Q resonances near the BICs,we achieve intense SPR with broadband tunability,potentially improving the radiation intensity by six orders compared to traditional methods.Experimentally,we validate the construction of BIC using plasmonic antennas and achieve broadband demonstration.Our proposed concept can be extended to other plasmonic or guided-wave systems,paving the way toward compact and efficient free-electron sources in hard-to-reach frequency regimes.

关键词： intense infinite enable

Finite Words,infinite Wisdom

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China Today 2024年第5期73卷 70-72页

作者： DENG DI 不详

As picture books gain popularity,they create a bridge between China and the rest of the world.

关键词： Finite infinite bridge

The infinite Universe of WUJI Looking Back at the Shining European Painting in the 20th Century

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China & The World Cultural Exchange 2022年第8期88卷 28-34页

作者： Jiang Haimei 不详

“The infinite Universe of WUJI”follows a timeline to show the historic turning point from the second half of the 19th century to the mid-20th century.It displays 62 masterpieces by 46 representative artists of the 20th century,including Vincent Willem Van Gogh,Amedeo Modigliani,Henri Matisse,Pablo Picasso,Wassily Kandinsky,Giorgio Morandi,Rene Magritte,Giorgio de Chirico and Lucio Fontana.They came from different schools of painting such as Belle Epoque,post-impressionism,fauvism,cubism,futurism,abstractism,surrealism,spatialism and art informal.This shows the development and change of Westerm painting in the past century.This is the first time in China to systematically sort out,research and display European modern and contemporary art.

关键词： turning infinite painting

infinite Regress and the Illusion of Actuality and Participationin Borges＇s The Aleph

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Journal of Literature and Art Studies 2017年第6期7卷 656-662页

作者： Robin McAllister Sacred Heart University Fairfield Ct. USA

Borges wants his reader to use imagination to participate in his fiction, to imagine the vision of the universe as anAleph. The vision of the Aleph is paradoxical, impossible, inexpressible--a point in space, in the basement of ahouse in Buenos Aires, where all other points in the universe are simultaneously present. The reader sees theAleph--or the illusion of the Aleph, watching it emerge as if through Borges＇ own eyes, as an unrequited lover andfrustrated poet gradually accommodating the infinite vision to the limitations of actual perception. The illusion ofactual presence the reader evokes seems to include the reader as both a subject reading and an object in the vision.The reader mirrors himself in the enumeration as the reader imaginatively projects associations and expectationsinto the images in order to make sense of them. The reader tries to avoid involving himself in the vision, but theimages the writer presents the reader with are ambiguous, schematic, demanding intervention to try to resolveapparently unresolved contradictions by trying out the different interpretations that may make sense of them. Overand over again in reading the enumeration the reader encounters images that allow him to convert sequence intosimultaneity, part into whole. Other images suggest the presence of infinite, multiple, perspectives on each objectconverging in the Aleph and reveal insights into hidden designs and into secret interiors of structures. The visionthe reader reads must seem to exceed the limits of language and perception. Opposed to images of disintegrationand chaotic dispersal are microcosmic images that suggest a whole reflected or contained in its parts, worldsreflected within worlds by infinite regress. infinite regress undermines the assumption of a subject and objectdichotomy in the act of reading and enhances the illusion of participation in the vision. infinite regress, imagewithin image, world within world, is a symmetry that asserts itself against the illusion of the enumeration asapparently random and

关键词： Borges, Aleph, infinite regress

Preparation of Superconducting Thin Films of infinite-Layer Nickelate Nd_(0.8)Sr_(0.2)NiO_(2)

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Chinese Physics Letters 2021年第7期38卷 136-139页

作者：高强赵宇辰周兴江朱志海 National Lab for Superconductivity Beijing National laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China Songshan Lake Materials Laboratory Dongguan 523808China

The recent observation of superconductivity in thin films of infinite-layer nickelate Nd_(0.8)Sr_(0.2)NiO_(2) has received considerable attention.Despite the many efforts to understand the superconductivity in infinite-layer nickelates,a consensus on the underlying mechanism for the superconductivity has yet to be reached,partly owing to the challenges with the material synthesis.Here,we report the successful growth of superconducting infinite-layer Nd_(0.8)Sr_(0.2)NiO_(2) films by pulsed laser deposition and soft chemical reduction.The details on the growth process are discussed.

关键词： synthesis reduction infinite

Constructing infinite Sequence Solutions for Space- Time Fractional Benjamin-Bona-Mahoney Equation

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Journal of Partial Differential Equations 2017年第3期30卷 189-200页

作者： KANG Zhouzheng College of Mathematics Inner Mongolia University for Nationalities Tongliao 028043China

In this article, the space-time fractional Benjamin-Bona-Mahoney equation is investigated via applying the first kind of elliptic equation method. As a result, based on the Backlund transformations and some seed solutions of the first kind of elliptic equation, families of infinite sequence solutions are presented. This approach is also applicable to many other nonlinear fractional differential equations.

关键词： Space-time fractional Benjamin-Bona-Mahoney equation Backlund transformations infinite sequence solutions.

A closed-form solution for a double infinite Euler-Bernoulli beam on a viscoelastic foundation subjected to harmonic line load

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 129-140页

作者： Li Bing Cheng Yongfeng Zhu Zhaoqing Zhang Fuyou Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Southeast University China Electric Power Research Institute Institute of Engineering Safety and Disaster Prevention Hohai University

The dynamic response of a double infinite beam system connected by a viscoelastic foundation under the harmonic line load is studied. The double infinite beam system consists of two identical and parallel beams, and the two beams are infinite elastic homogeneous and isotropic. A viscoelastic layer connects the two beams continuously. To decouple the two coupled equations governing the response of the double infinite beam system, a variable substitution method is introduced. The frequency domain solutions of the decoupled equations are obtained by using Fourier transforms as well as Laplace transforms successively. The time domain solution in the generalized integral form are then obtained by employing the corresponding inverse transforms, i.e. Fourier transform and inverse Laplace transform. The solution is verified by numerical examples, and the effects of parameters on the response are also investigated.

关键词： infinite two double beam transforms

Vectorial approximations of infinite-dimensional covariance descriptors for image classification

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Computational Visual Media 2017年第4期3卷 379-385页

作者： Jie-Yi Ren Xiao-Jun Wu School of Io T Engineering Jiangnan UniversityWuxi 214122China

The class of symmetric positive definite(SPD)matrices,especially in the form of covariance descriptors(Cov Ds),have been receiving increased interest for many computer vision tasks.Covariance descriptors offer a compact way of robustly fusing different types of features with measurement variations.Successful examples of applying Cov Ds addressing various classification problems

关键词： covariance infinite Riemannian symmetric matrices applying dimensionality classifier Euclidean kernel