A new frequency-selective surface(FSS)with loadings is introduced in this paper and analyzed by way of period moment methods(PMMs).The simulated results show that FSS may operate in different bands and especially gene...A new frequency-selective surface(FSS)with loadings is introduced in this paper and analyzed by way of period moment methods(PMMs).The simulated results show that FSS may operate in different bands and especially generate a large reduction in the resonant frequency for a fixed unit cell size through different loadings.This provides a new orientation in the development for FSS.Practical circuits are fabricated,and the measured results agree well with the simulated results.展开更多
In the FEM dynamic analysis of large flexible space structure (LFSS), thesolution of frequencies and corresponding models is actually a general eigenvalueand eigenvector problem. In this article, Lanczos method was ap...In the FEM dynamic analysis of large flexible space structure (LFSS), thesolution of frequencies and corresponding models is actually a general eigenvalueand eigenvector problem. In this article, Lanczos method was applied to thistype of problem. In numerical examples, the convergency, accuracy-time relationand multi-root problem of Lanczos method for beam structure were analyzed.Considering the characteristic of the stiffness matrix of beam structure, the authoralso present some ideas to improve Lanczos method by iteration method.展开更多
基金This work was supported by the Major Fundamental Preliminary Research Foundation for National Security(No.51307).
文摘A new frequency-selective surface(FSS)with loadings is introduced in this paper and analyzed by way of period moment methods(PMMs).The simulated results show that FSS may operate in different bands and especially generate a large reduction in the resonant frequency for a fixed unit cell size through different loadings.This provides a new orientation in the development for FSS.Practical circuits are fabricated,and the measured results agree well with the simulated results.
文摘In the FEM dynamic analysis of large flexible space structure (LFSS), thesolution of frequencies and corresponding models is actually a general eigenvalueand eigenvector problem. In this article, Lanczos method was applied to thistype of problem. In numerical examples, the convergency, accuracy-time relationand multi-root problem of Lanczos method for beam structure were analyzed.Considering the characteristic of the stiffness matrix of beam structure, the authoralso present some ideas to improve Lanczos method by iteration method.
