Earth medium is not completely elastic, with its viscosity resulting in attenuation and dispersion of seismic waves. Most viscoelastic numerical simulations are based on the finite-difference and finite-element method...Earth medium is not completely elastic, with its viscosity resulting in attenuation and dispersion of seismic waves. Most viscoelastic numerical simulations are based on the finite-difference and finite-element methods. Targeted at viscoelastic numerical modeling for multilayered media, the constant-Q acoustic wave equation is transformed into the corresponding wave integral representation with its Green's function accounting for viscoelastic coefficients. An efficient alternative for full-waveform solution to the integral equation is proposed in this article by extending conventional frequency-domain boundary element methods to viscoelastic media. The viscoelastic boundary element method enjoys a distinct characteristic of the explicit use of boundary continuity conditions of displacement and traction, leading to a semi-analytical solution with sufficient accuracy for simulating the viscoelastic effect across irregular interfaces. Numerical experiments to study the viscoelastic absorption of different Q values demonstrate the accuracy and applicability of the method.展开更多
This research is based on the implementation of interactive and exploratory teaching methods in college English courses.The analysis done for this research signifies the importance of interactive-exploratory teaching ...This research is based on the implementation of interactive and exploratory teaching methods in college English courses.The analysis done for this research signifies the importance of interactive-exploratory teaching methods,identifying the characteristics of interactive teaching methods,and specifying the purpose of conducting interactive-exploratory teaching methods as a reference for educators.展开更多
基金supported by the National Natural Science Foundation of China (No. 41130418)the Strategic Leading Science and Technology Programme (Class B) of the Chinese Academy of Sciences (No. XDB10010400)
文摘Earth medium is not completely elastic, with its viscosity resulting in attenuation and dispersion of seismic waves. Most viscoelastic numerical simulations are based on the finite-difference and finite-element methods. Targeted at viscoelastic numerical modeling for multilayered media, the constant-Q acoustic wave equation is transformed into the corresponding wave integral representation with its Green's function accounting for viscoelastic coefficients. An efficient alternative for full-waveform solution to the integral equation is proposed in this article by extending conventional frequency-domain boundary element methods to viscoelastic media. The viscoelastic boundary element method enjoys a distinct characteristic of the explicit use of boundary continuity conditions of displacement and traction, leading to a semi-analytical solution with sufficient accuracy for simulating the viscoelastic effect across irregular interfaces. Numerical experiments to study the viscoelastic absorption of different Q values demonstrate the accuracy and applicability of the method.
基金Heilongjiang Province Economic and Social Development Key Research Project:Research on the Theory and Practice of Foreign Language Education in Heilongjiang Colleges and Universities from a Cross-cultural Perspective(WY2019037-B)The 2019 Harbin Engineering University undergraduate teaching reform research project research-based teaching and process assessment special project“Analysis and Research on Learning Motivation and Strategies of Ethnic Minority Undergraduates in Local Universities under the Background of Double First-class”(JG2019B87).
文摘This research is based on the implementation of interactive and exploratory teaching methods in college English courses.The analysis done for this research signifies the importance of interactive-exploratory teaching methods,identifying the characteristics of interactive teaching methods,and specifying the purpose of conducting interactive-exploratory teaching methods as a reference for educators.