The surface mode propagation along a dielectric slab waveguide which consists of the core and substrate of right handed materials (RHM) and the cover of left handed materials (LHM) is studied. The normalized frequency...The surface mode propagation along a dielectric slab waveguide which consists of the core and substrate of right handed materials (RHM) and the cover of left handed materials (LHM) is studied. The normalized frequency and normalized propagation constant are introduced to the left-handed material slab waveguides. The dispersion relations expressed by the normalized parameters are derived. Universal dispersion curves are obtained analytically. Based on that, the dispersion properties differ dramatically for different LHM constitutive parameters, the surface TE0 and TE1 modes are internatively obtained. It shows that two different kinds of TE modes compensate each other to form a whole mode.展开更多
Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quan...Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration展开更多
基金supported by National Natural ScienceFoundation of China (Grant No. 60577043 and 60571054)Creative Graduate Student Foundation of Shanghai Uni-versity (Grant No. 080153).
文摘The surface mode propagation along a dielectric slab waveguide which consists of the core and substrate of right handed materials (RHM) and the cover of left handed materials (LHM) is studied. The normalized frequency and normalized propagation constant are introduced to the left-handed material slab waveguides. The dispersion relations expressed by the normalized parameters are derived. Universal dispersion curves are obtained analytically. Based on that, the dispersion properties differ dramatically for different LHM constitutive parameters, the surface TE0 and TE1 modes are internatively obtained. It shows that two different kinds of TE modes compensate each other to form a whole mode.
文摘Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration