Traditional vortex beam parameter determination methods are all designed for aberration-free vortex beams.In the case of aberrations and turbulence,they tend to struggle in mutual restraint between phase recovery and ...Traditional vortex beam parameter determination methods are all designed for aberration-free vortex beams.In the case of aberrations and turbulence,they tend to struggle in mutual restraint between phase recovery and topological charge(TC)detection.Most recent methods depend on complex interferometric setups and precise phase singularity localization.An iterative virtual Moiréreconstruction(IVMR)technique is proposed based on the blind conformal mapping,achieving simultaneous demodulation of TC and phase from a single-frame aberrated interferogram,not needing precise phase singularity positioning.展开更多
A finite element formulation was presented for the nonlinear free vibration of thin-walled curved beams with non-symmetric open across section. The kinetic and potential energies were derived by the virtual principle....A finite element formulation was presented for the nonlinear free vibration of thin-walled curved beams with non-symmetric open across section. The kinetic and potential energies were derived by the virtual principle. The energy function includes the effect of fiexural-torsional coupling, the torsion warping and the shear centre location. For finite element analysis, cubic polynomials were utilized as the shape functions of the two nodal thin-walled curved elements. Each node possesses seven degrees freedom including the warping degree of freedom. The nonlinear eigenvalue problem was solved by the direct iteration technique. The results are compared with those for straight beams as available in the literature. The results for nonlinear free vibration analysis of curved beams for various radii and subtended angle are presented.展开更多
基金National Natural Science Foundation of China(52275515)National Key Research and Development Program of China(2024YFE03000200)Open Funding of Magnetic Confinement Fusion Laboratory of Modern Manufacturing Quality Engineering(K13092055)。
文摘Traditional vortex beam parameter determination methods are all designed for aberration-free vortex beams.In the case of aberrations and turbulence,they tend to struggle in mutual restraint between phase recovery and topological charge(TC)detection.Most recent methods depend on complex interferometric setups and precise phase singularity localization.An iterative virtual Moiréreconstruction(IVMR)technique is proposed based on the blind conformal mapping,achieving simultaneous demodulation of TC and phase from a single-frame aberrated interferogram,not needing precise phase singularity positioning.
文摘A finite element formulation was presented for the nonlinear free vibration of thin-walled curved beams with non-symmetric open across section. The kinetic and potential energies were derived by the virtual principle. The energy function includes the effect of fiexural-torsional coupling, the torsion warping and the shear centre location. For finite element analysis, cubic polynomials were utilized as the shape functions of the two nodal thin-walled curved elements. Each node possesses seven degrees freedom including the warping degree of freedom. The nonlinear eigenvalue problem was solved by the direct iteration technique. The results are compared with those for straight beams as available in the literature. The results for nonlinear free vibration analysis of curved beams for various radii and subtended angle are presented.
