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Analytical Property
The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Wenshinn Shyu – One of the best experts on this subject based on the ideXlab platform.

sh wave scattering by a semi elliptical hill using a null field boundary integral equation method and a hybrid method
Geophysical Journal International, 2012CoAuthors: Jengtzong Chen, Wenshinn ShyuAbstract:SUMMARY Following the success of seismic analysis of a semicircular hill, the problem of SHwave scattering by a semielliptical hill is revisited by using the nullfield boundary integral equation method (BIEM). To fully use the Analytical Property in the nullfield boundary integral equation approach in conjunction with degenerate kernels for solving the semielliptical hill scattering problem, the problem is decomposed to two regions to produce elliptical boundaries by using the technique of taking free body. One is the halfplane problem containing a semielliptical boundary. This semiinfinite problem is imbedded in an infinite plane with an artificial elliptical boundary such that degenerate kernel can be fully applied. The other is an interior problem bounded by an elliptical boundary. The degenerate kernel in the elliptic coordinates for two subdomains is used to expand the closedform fundamental solution. The semiAnalytical formulation in companion with matching boundary conditions yields six constraint equations. Instead of finding admissible waveexpansion bases, our nullfield BIEM in conjunction with degenerate kernels has the five features over the conventional BIEM/BEM, (1) free of calculating principal values, (2) exponential convergence, (3) elimination of boundarylayer effect, (4) meshless and (5) wellposed system. All numerical results are compared well with those of using the hybrid method which is also described in this paper. It is interesting to find that a focusing phenomenon is also observed in this study.
Jengtzong Chen – One of the best experts on this subject based on the ideXlab platform.

sh wave scattering by a semi elliptical hill using a null field boundary integral equation method and a hybrid method
Geophysical Journal International, 2012CoAuthors: Jengtzong Chen, Wenshinn ShyuAbstract:SUMMARY Following the success of seismic analysis of a semicircular hill, the problem of SHwave scattering by a semielliptical hill is revisited by using the nullfield boundary integral equation method (BIEM). To fully use the Analytical Property in the nullfield boundary integral equation approach in conjunction with degenerate kernels for solving the semielliptical hill scattering problem, the problem is decomposed to two regions to produce elliptical boundaries by using the technique of taking free body. One is the halfplane problem containing a semielliptical boundary. This semiinfinite problem is imbedded in an infinite plane with an artificial elliptical boundary such that degenerate kernel can be fully applied. The other is an interior problem bounded by an elliptical boundary. The degenerate kernel in the elliptic coordinates for two subdomains is used to expand the closedform fundamental solution. The semiAnalytical formulation in companion with matching boundary conditions yields six constraint equations. Instead of finding admissible waveexpansion bases, our nullfield BIEM in conjunction with degenerate kernels has the five features over the conventional BIEM/BEM, (1) free of calculating principal values, (2) exponential convergence, (3) elimination of boundarylayer effect, (4) meshless and (5) wellposed system. All numerical results are compared well with those of using the hybrid method which is also described in this paper. It is interesting to find that a focusing phenomenon is also observed in this study.

sh wave diffraction by a semi circular hill revisited a null field boundary integral equation method using degenerate kernels
Soil Dynamics and Earthquake Engineering, 2011CoAuthors: Jengtzong Chen, Chinefeng Wu, I L ChenAbstract:Abstract Following the success of seismic analysis of a canyon [1], the problem of SHwave diffraction by a semicircular hill is revisited using the nullfield boundary integral equation method (BIEM). To fully utilize the Analytical Property in the nullfield boundary integral equation approach in conjunction with degenerate kernels for solving the semicircular hill scattering problem, the problem is decomposed into two regions to produce circular boundaries using the technique of taking free body. One is the halfplane problem containing a semicircular boundary. This semiinfinite problem is imbedded in an infinite plane with an artificial full circular boundary such that degenerate kernel can be fully applied. The other is an interior problem bounded by a circular boundary. The degenerate kernel in the polar coordinates for two subdomains is utilized for the closedform fundamental solution. The semiAnalytical formulation along with matching boundary conditions yields six constraint equations. Instead of finding admissible wave expansion bases, our nullfield BIEM approach in conjunction with degenerate kernels have five features over the conventional BIEM/BEM: (1) free from calculating principal values, (2) exponential convergence, (3) elimination of boundarylayer effect, (4) meshless and (5) wellposed system. All the numerical results are comparing well with the available results in the literature. It is interesting to find that a focusing phenomenon is also observed in this study.
Deling Zeng – One of the best experts on this subject based on the ideXlab platform.

Analytical Property of scattering matrix spectroscopy phenomena and sharp overlapping autoionization resonances
Scientific Reports, 2017CoAuthors: Rui Jin, Xiaoying Han, Xiang Gao, Deling ZengAbstract:An extended atomic data base with sufficiently high precision is required in astrophysics studies and the energy researches. For example, there are “infinite” energy levels in discrete energy region as well as overlapping resonances in autoionization region. We show in this paper the merits of our relativistic eigenchannel Rmatrix method RREigen based on the Analytical continuation properties of scattering matrices for the calculations of the energy levels, overlapping resonances and the related transitions. Using Ne+ as an illustration example, the scattering matrices of Ne+ in both discrete and continuum energy regions are calculated by our RREigen method directly. Based on our proposed projected high dimensional quantumdefect graph (symmetrized), one can readily determine the accuracies of the calculated scattering matrices using the experimental energy levels in a systematical way. The calculated resonant photoionization cross sections in the autoionization region are in excellent agreement with the benchmark high resolution experiments. With the scattering matrices checked/calibrated against spectroscopy data in both discrete and continuum energy regions, the relevant dynamical processes should be calculated with adequate accuracies. It should then satisfy the needs of the astrophysical and energy researches.
Rui Jin – One of the best experts on this subject based on the ideXlab platform.

Analytical Property of scattering matrix spectroscopy phenomena and sharp overlapping autoionization resonances
Scientific Reports, 2017CoAuthors: Rui Jin, Xiaoying Han, Xiang Gao, Deling ZengAbstract:An extended atomic data base with sufficiently high precision is required in astrophysics studies and the energy researches. For example, there are “infinite” energy levels in discrete energy region as well as overlapping resonances in autoionization region. We show in this paper the merits of our relativistic eigenchannel Rmatrix method RREigen based on the Analytical continuation properties of scattering matrices for the calculations of the energy levels, overlapping resonances and the related transitions. Using Ne+ as an illustration example, the scattering matrices of Ne+ in both discrete and continuum energy regions are calculated by our RREigen method directly. Based on our proposed projected high dimensional quantumdefect graph (symmetrized), one can readily determine the accuracies of the calculated scattering matrices using the experimental energy levels in a systematical way. The calculated resonant photoionization cross sections in the autoionization region are in excellent agreement with the benchmark high resolution experiments. With the scattering matrices checked/calibrated against spectroscopy data in both discrete and continuum energy regions, the relevant dynamical processes should be calculated with adequate accuracies. It should then satisfy the needs of the astrophysical and energy researches.
I L Chen – One of the best experts on this subject based on the ideXlab platform.

sh wave diffraction by a semi circular hill revisited a null field boundary integral equation method using degenerate kernels
Soil Dynamics and Earthquake Engineering, 2011CoAuthors: Jengtzong Chen, Chinefeng Wu, I L ChenAbstract:Abstract Following the success of seismic analysis of a canyon [1], the problem of SHwave diffraction by a semicircular hill is revisited using the nullfield boundary integral equation method (BIEM). To fully utilize the Analytical Property in the nullfield boundary integral equation approach in conjunction with degenerate kernels for solving the semicircular hill scattering problem, the problem is decomposed into two regions to produce circular boundaries using the technique of taking free body. One is the halfplane problem containing a semicircular boundary. This semiinfinite problem is imbedded in an infinite plane with an artificial full circular boundary such that degenerate kernel can be fully applied. The other is an interior problem bounded by a circular boundary. The degenerate kernel in the polar coordinates for two subdomains is utilized for the closedform fundamental solution. The semiAnalytical formulation along with matching boundary conditions yields six constraint equations. Instead of finding admissible wave expansion bases, our nullfield BIEM approach in conjunction with degenerate kernels have five features over the conventional BIEM/BEM: (1) free from calculating principal values, (2) exponential convergence, (3) elimination of boundarylayer effect, (4) meshless and (5) wellposed system. All the numerical results are comparing well with the available results in the literature. It is interesting to find that a focusing phenomenon is also observed in this study.