We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the sam...We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the same pattern but with the previous generation as the basic building blocks. We calculate the transmission spectrum which shows the multifractal behavior for systems with large generation index. From the analysis of the average resistivity and the multifractal structure of the wavefunctions, we show that there exist different types of states exhibiting extended, localized and intermediate characteristics. The degree of localization is sensitive to the variation of the structural parameters.Suggestion of the possible experimental realization is discussed.展开更多
Geological structures often exhibit smooth characteristics away from sharp discontinuities. One aim of geophysical inversion is to recover information about the smooth structures as well as about the sharp discontinui...Geological structures often exhibit smooth characteristics away from sharp discontinuities. One aim of geophysical inversion is to recover information about the smooth structures as well as about the sharp discontinuities. Because no specific operator can provide a perfect sparse representation of complicated geological models, hyper-parameter regularization inversion based on the iterative split Bregman method was used to recover the features of both smooth and sharp geological structures. A novel preconditioned matrix was proposed, which counteracted the natural decay of the sensitivity matrix and its inverse matrix was calculated easily. Application of the algorithm to synthetic data produces density models that are good representations of the designed models. The results show that the algorithm proposed is feasible and effective.展开更多
This paper analyzes multiple structural changes by GMDH （Group Meth- ods of Data Handling）, which have obvious advantages. Our method extends the model of Lumsdaine ＆ Papell[1] （1997）, and it could be applied to ...This paper analyzes multiple structural changes by GMDH （Group Meth- ods of Data Handling）, which have obvious advantages. Our method extends the model of Lumsdaine ＆ Papell[1] （1997）, and it could be applied to the case of more than two structural changes. Because of simultaneously considering every structural change of the hypothesis, it is likely to be of particular relevance in practice. And it can decrease large investigation costs by MATLAB programming. What is more, we can select the criterion value of F incremental statistic to control the significance of the breaks, based on kinds of investigation intentions. And the empirical evidences on Shenzhen Composite Index are presented to illustrate the usefulness of our method.展开更多
文摘We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the same pattern but with the previous generation as the basic building blocks. We calculate the transmission spectrum which shows the multifractal behavior for systems with large generation index. From the analysis of the average resistivity and the multifractal structure of the wavefunctions, we show that there exist different types of states exhibiting extended, localized and intermediate characteristics. The degree of localization is sensitive to the variation of the structural parameters.Suggestion of the possible experimental realization is discussed.
基金Projects(41174061,41374120)supported by the National Natural Science Foundation of China
文摘Geological structures often exhibit smooth characteristics away from sharp discontinuities. One aim of geophysical inversion is to recover information about the smooth structures as well as about the sharp discontinuities. Because no specific operator can provide a perfect sparse representation of complicated geological models, hyper-parameter regularization inversion based on the iterative split Bregman method was used to recover the features of both smooth and sharp geological structures. A novel preconditioned matrix was proposed, which counteracted the natural decay of the sensitivity matrix and its inverse matrix was calculated easily. Application of the algorithm to synthetic data produces density models that are good representations of the designed models. The results show that the algorithm proposed is feasible and effective.
文摘This paper analyzes multiple structural changes by GMDH （Group Meth- ods of Data Handling）, which have obvious advantages. Our method extends the model of Lumsdaine ＆ Papell[1] （1997）, and it could be applied to the case of more than two structural changes. Because of simultaneously considering every structural change of the hypothesis, it is likely to be of particular relevance in practice. And it can decrease large investigation costs by MATLAB programming. What is more, we can select the criterion value of F incremental statistic to control the significance of the breaks, based on kinds of investigation intentions. And the empirical evidences on Shenzhen Composite Index are presented to illustrate the usefulness of our method.
