The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous d...The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface.展开更多
In this paper, as is studied are the electro-elastic solutions for a piezoelectric halfspace subjected Io a line force, a line charge and a line dislocation, i. e.. Green sfunclions on the basis of Stroh formalism and...In this paper, as is studied are the electro-elastic solutions for a piezoelectric halfspace subjected Io a line force, a line charge and a line dislocation, i. e.. Green sfunclions on the basis of Stroh formalism and the concept of analytical continuation,explicit expressions for Green's functions are derived. As a direct application of theresults obtained, an infinite piezoelectric solid containing a semi-infinite crack isexammed. Attention iffocused on the stress and electric displacement fields of a cracktip. The stress and electric displacement intensity .factors are given explicitly.展开更多
In this proceeding, I review the attempts to calculate the Nucleon resonance （including Roper as first radially excited state of nucleon and other excited states） using lattice quantum chromodynamics （QCD）. The la...In this proceeding, I review the attempts to calculate the Nucleon resonance （including Roper as first radially excited state of nucleon and other excited states） using lattice quantum chromodynamics （QCD）. The latest preliminary results from Hadron Spectrum Collaboration （HSC） with mπ≈ 380 MeV are reported. The Sachs electric form factor of the proton and neutron and their transition with the Roper at large Q2 are also updated in this work.展开更多
In this paper,a transversely isotropic piezoelectric half-space with the isotropy axis parallel to the z-axis is considered under rotation on a rigid circular disk bonded to the surface of the piezoelectric medium.Thi...In this paper,a transversely isotropic piezoelectric half-space with the isotropy axis parallel to the z-axis is considered under rotation on a rigid circular disk bonded to the surface of the piezoelectric medium.This is a type of Reissner-Sagoci mixed boundary value problem.By utilizing the Hankel transform,the mixed boundary value problem is simplified into solving a pair of dual integral equations.Full-field analytical expressions for displacement,stresses,and electric displacement inside the half-space are obtained.The shear stresses and electric displacement on the surface are found to be singular at the edge of the rigid circular disk,and the stress intensity factors and electric displacement intensity factor are defined.Numerical results show that material properties and geometric size have significant effects on displacement,shear stresses,and electric displacement.展开更多
基金the National Natural Science Foundation of China (No.10072041)the National Excellent Young Scholar Fund of China (No.10125209)the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutions of MOE,P.R.C..
文摘The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface.
文摘In this paper, as is studied are the electro-elastic solutions for a piezoelectric halfspace subjected Io a line force, a line charge and a line dislocation, i. e.. Green sfunclions on the basis of Stroh formalism and the concept of analytical continuation,explicit expressions for Green's functions are derived. As a direct application of theresults obtained, an infinite piezoelectric solid containing a semi-infinite crack isexammed. Attention iffocused on the stress and electric displacement fields of a cracktip. The stress and electric displacement intensity .factors are given explicitly.
基金Supported by Jefferson Science Associates, LLC under U.S. DOE (DE-AC05-06OR23177)
文摘In this proceeding, I review the attempts to calculate the Nucleon resonance （including Roper as first radially excited state of nucleon and other excited states） using lattice quantum chromodynamics （QCD）. The latest preliminary results from Hadron Spectrum Collaboration （HSC） with mπ≈ 380 MeV are reported. The Sachs electric form factor of the proton and neutron and their transition with the Roper at large Q2 are also updated in this work.
基金supported by the National Natural Science Foundation of China(11872203)the Creative Research Groups(51921003).
文摘In this paper,a transversely isotropic piezoelectric half-space with the isotropy axis parallel to the z-axis is considered under rotation on a rigid circular disk bonded to the surface of the piezoelectric medium.This is a type of Reissner-Sagoci mixed boundary value problem.By utilizing the Hankel transform,the mixed boundary value problem is simplified into solving a pair of dual integral equations.Full-field analytical expressions for displacement,stresses,and electric displacement inside the half-space are obtained.The shear stresses and electric displacement on the surface are found to be singular at the edge of the rigid circular disk,and the stress intensity factors and electric displacement intensity factor are defined.Numerical results show that material properties and geometric size have significant effects on displacement,shear stresses,and electric displacement.
