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A numerical method based on boundary integral equations and radial basis functions for plane anisotropic thermoelastostatic equations with general variable coefficients

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Applied Mathematics and Mechanics(english edition) 2020年第4期41卷 551-566页

作者： w.T.ang X.wang School of Mechanical and Aerospace engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Mechanical engineering National University of SingaporeSingapore 117575Singapore

A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable coe?cients. The equations describe the thermoelastic behaviors of nonhomogeneous anisotropic materials with properties that vary smoothly from point to point in space. No restriction is imposed on the spatial variations of the thermoelastic coe?cients as long as all the requirements of the laws of physics are satis?ed. To check the validity and accuracy of the proposed numerical method, some speci?c test problems with known solutions are solved.

关键词： elliptic partial differential equation variable coefficient boundary element method radial basis function anisotropic thermoelastostatics

A micromechanical model based on hypersingular integro-differential equations for analyzing micro-crazed interfaces between dissimilar elastic materials

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Applied Mathematics and Mechanics(english edition) 2020年第2期41卷 193-206页

作者： X.wang w.T.ang H.FAN School of Mechanical and Aerospace engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

The current work models a weak(soft) interface between two elastic materials as containing a periodic array of micro-crazes. The boundary conditions on the interfacial micro-crazes are formulated in terms of a system of hypersingular integro-differential equations with unknown functions given by the displacement jumps across opposite faces of the micro-crazes. Once the displacement jumps are obtained by approximately solving the integro-differential equations, the effective stiffness of the micro-crazed interface can be readily computed. The effective stiffness is an important quantity needed for expressing the interfacial conditions in the spring-like macro-model of soft interfaces. Specific case studies are conducted to gain physical insights into how the effective stiffness of the interface may be influenced by the details of the interfacial micro-crazes.

关键词： micromechanical modeling micro-crazed interface effective stiffness coefficient hypersingular integro-differential equation

A novel method for clustering cellular data to improve classification

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Neural Regeneration Research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George Mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia Mouselight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification levene's one-tailed statistical test unsupervised hierarchical clustering

An Overview of Self-piercing Riveting Process with Focus on Joint Failures, Corrosion Issues and Optimisation Techniques

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Chinese Journal of Mechanical engineering 2021年第1期34卷 89-113页

作者： Hua Qian ang School of engineering RMIT UniversityBundooraVictoria 3083Australia

Self-piercing riveting(SPR)is a cold forming technique used to fasten together two or more sheets of materials with a rivet without the need to predrill a *** application of SPR in the automotive sector has become increasingly popular mainly due to the growing use of lightweight materials in transportation ***,SPR joining of these advanced light materials remains a challenge as these materials often lack a good combination of high strength and ductility to resist the large plastic deformation induced by the SPR *** this paper,SPR joints of advanced materials and their corresponding failure mechanisms are discussed,aiming to provide the foundation for future improvement of SPR joint *** paper is divided into three major sections:1)joint failures focusing on joint defects originated from the SPR process and joint failure modes under different mechanical loading conditions,2)joint corrosion issues,and 3)joint optimisation via process parameters and advanced techniques.

关键词： Self-piercing riveting Mechanical joining Joint defects Failure mechanisms Corrosion Joint optimisation

Multi-affine registration using local polynomial expansion

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Journal of Zhejiang University-Science C(Computers and electronics) 2010年第7期11卷 495-503页

作者： Yuan-jun w'ang Guimar FARNeBACK Carl-Fredrik weSTIN Digital Medical Research Center Shanghai Medical School Fudan University Shanghai 200032 China lab of Mathematics in Imaging Brigham and Women's Hospital Harvard Medical School Boston 02115 MA USA

In this paper, we present a non-linear (multi-affine) registration algorithm based on a local polynomial expansion model. we generalize previous work using a quadratic polynomial expansion model. local affine models are estimated using this generalized model analytically and iteratively, and combined to a deformable registration algorithm. experiments show that the affine parameter calculations derived from this quadratic model are more accurate than using a linear model. experiments further indicate that the multi-affine deformable registration method can handle complex non-linear deformation fields necessary for deformable registration, and a faster convergent rate is verified from our comparison experiment.

关键词： Deformable registration Polynomial expansion least squares Multi-affine Normalized convolution

Genistein:a possible solution for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2903-2905页

作者： Karolina Pierzynowska Bartosz Karaszewski Grzegorz węgrzyn Department of Molecular Biology University of GdanskGdanskPoland Gdansk Polandand Department of Adult NeurologyFaculty of MedicineMedical University of GdanskGdanskPoland

Neurodegenerative diseases are defined as disorders resulting from the slow and progressive loss of function and eventual death of neural cells that result from the primary pathology of nervous *** can lead to severe nervous system dysfunction,eventually affecting multiple organs and *** hundred neurodegenerative diseases have been described,and owing to their prevalence,severity.

关键词： organs Alzheimer death

Broadband strong optical dichroism in topological Dirac semimetals with Fermi velocity anisotropy

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Chinese Physics B 2020年第7期29卷 128-134页

作者： J lim K J A Ooi C Zhang l K ang Yee Sin ang Science Math and TechnologySingapore University of Technology and DesignSingapore School of energy and Chemical engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia College of Chemistry and Chemical engineering Xiamen UniversityXiamen 361005China School of Physics University of WollongongNorthfields AvenueNew South Wales 2522Australia

Prototypical three-dimensional(3D)topological Dirac semimetals(DSMs),such as Cd3As2 and Na3Bi,contain electrons that obey a linear momentum-energy dispersion with different Fermi velocities along the three orthogonal momentum *** being extensively studied in recent years,the inherent Fermi velocity anisotropy has often been neglected in the theoretical and numerical studies of 3D *** this omission does not qualitatively alter the physics of light-driven massless quasiparticles in 3D DSMs,it does quantitatively change the optical coefficients which can lead to nontrivial implications in terms of nanophotonics and plasmonics *** we study the linear optical response of 3D DSMs for general Fermi velocity values along each *** the signature conductivity-frequency scaling,σ(ω)∝ω,of 3D Dirac fermion is well-protected from the Fermi velocity anisotropy,the linear optical response exhibits strong linear dichroism as captured by the universal extinction ratio scaling law,Λi j=(vi/v j)^2(where i=j denotes the three spatial coordinates x,y,z,and vi is the i-direction Fermi velocity),which is independent of frequency,temperature,doping,and carrier scattering *** Cd3As2 and Na3Bi3,an exceptionally strong extinction ratio larger than 15 and covering a broad terahertz window is *** findings shed new light on the role of Fermi velocity anisotropy in the optical response of Dirac semimetals and open up novel polarization-sensitive functionalities,such as photodetection and light modulation.

关键词： topological Dirac semimetal optical anisotropy linear dichroismn linear response theory

DYNAMICS ON NONCOMMUTATIVe ORlICZ SPACeS

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Acta Mathematica Scientia 2020年第5期40卷 1249-1270页

作者： l.e.lABUSCHAGNe w.A.MAJewSKI DSI-NRF Coe in Mathematics and Statistics Science Focus Area for PAAInternal Box 209School of Mathematics and Statistics Science NWUPVT.BAG X60012520 Potchef stroomSouth Africa Focus Area for PAA North-West-UniversityPotchef stroomSouth Africa

Quantum dynamical maps are defined and studied for quantum statistical physics based on Orlicz *** complements earlier work[26]where we made a strong case for the assertion that statistical physics of regular systems should properly be based on the pair of Orlicz spaces(lcosh-1,l log(l+1)),since this framework gives a better description of regular observables,and also allows for a well-defined entropy *** the present paper we"complete"the picture by addressing the issue of the dynamics of such a system,as described by a Markov semigroup corresponding to some Dirichlet form(see[4,13,14]).Specifically,we show that even in the most general non-commutative contexts,completely positive Markov maps satisfying a natural Det ailed Balance condition canonically admit an action on a large class of quantum Orlicz *** is achieved by the development of a new interpolation strategy for extending the action of such maps to the appropriate intermediate spaces of the pair(l∞,l1).As a consequence,we obtain that completely positive quantum Markov dynamics naturally extends to the context proposed in[26].

关键词： det ailed balance Orlicz space Markov semigroup comple tely positive

Role of interstitial flow in tumor migration through 3D eCM

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Acta Mechanica Sinica 2020年第3期36卷 768-774页

作者： ang li Ren Sun MOe Key laboratory of Hydrodynamics School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Cancer invasion in tissue is simultaneously regulated by chemical and mechanical *** suggest that interstitial flow plays a critical role in tumor *** one hand,the distribution of chemokines around cell is influenced by *** the other hand,interstitial flow may reconfigure the alignment of fiber matrix,which greatly changes the contact force between cell and extracellular *** this study,we have upgraded a model by which we can quantitatively investigate the influence of flow on tumor cell migration.A hydrodynamic analysis of shear stress on a slender body is introduced to simulate the fiber *** such as subtle flow and cell-matrix interaction which dominate tumor migration are integrated in this novel *** results show interstitial flow facilitates tumor cell migration in the flow ***,the flow-related chemical and mechanical cues have a synergistic effect on the *** model provides better understanding on cancer metastasis and helps design vitro experiment precisely.

关键词： Interstitial flow Tumor cell migration extracellular matrix