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31.
由于几何秩在线性等距映射下是不变的,因此几何秩是研究算子代数线性等距映射的一个强有力的工具.证明了在一定条件下,套代数弱闭模中的n秩算子的几何秩的上、下界分别为n2和n(n+1)2,这表明套代数弱闭模中有限秩算子的充要条件是算子的几何秩有限. 相似文献
32.
M. E. Burgos 《Foundations of Physics》2008,38(10):883-907
We present three different derivations of the transition probabilities to the continuum. It is shown that calculations, performed
as a direct application of the postulates of orthodox quantum mechanics (OQM), do not yield results consistent with experiments.
Traditional treatments are summarized and criticized. The relation of the transitions to the continuum with the traditional
quantum measurement problem is pointed out; we sum up and comment some contributions concerning this issue. It is shown that
an approach based on the notion of spontaneous projections yields expressions of the transition probabilities similar to those
obtained in the traditional way and new predictions which could be submitted to experimental tests. 相似文献
33.
Yu-Qiu Zhao 《Journal of Elasticity》1997,46(3):199-216
The plane stress boundary value problem of quasi-static linear orthotropic thermoelasticity is discussed. The thermoelastic system on a bounded simply-connected domain is decoupled. The decoupled temperature equation is investigated by using accurate estimation and the contraction mapping principle. Representations of solutions of the field equation are obtained, and some solvability results are proved. The results are of both theoretical and numerical interest. 相似文献
34.
FRACTAL PROPERTIES OF STATISTICALLY SELF-SIMILAR SETS I 总被引:1,自引:1,他引:0
In this paper,authors compute the Packing dimension of statistically selfsimilar sets and obtaine the dimension and dimension distribution of statistically selfsimilar measure. 相似文献
35.
We study the multiple-sets split feasibility problem that requires to find a point closest to a family of closed convex sets in one space such that its image under a linear transformation will be closest to another family of closed convex sets in the image space. By casting the problem into an equivalent problem in a suitable product space we are able to present a simultaneous subgradients projections algorithm that generates convergent sequences of iterates in the feasible case. We further derive and analyze a perturbed projection method for the multiple-sets split feasibility problem and, additionally, furnish alternative proofs to two known results. 相似文献
36.
N. K. Bliev 《Siberian Mathematical Journal》2006,47(1):28-34
We single out the Besov spaces that embed into the class of continuous functions and enjoy the Fredholm theory of linear singular integral equations with Cauchy kernel. We give basic results of this theory in the class of continuous (rather than Holder continuous) functions in terms of Besov spaces. Alongside elliptic operators we consider violations of ellipticity: the degeneration of the symbol of an operator at finitely many points. 相似文献
37.
序压缩映射的不动点定理 总被引:22,自引:0,他引:22
本文在序Banach空间中引入了几种按序压缩的压缩型映射,证明了相应的不动点定理. 相似文献
38.
The successive projections algorithm (SPA) is widely used to select variables for multiple linear regression (MLR) modeling. However, SPA used only once may not obtain all the useful information of the full spectra, because the number of selected variables cannot exceed the number of calibration samples in the SPA algorithm. Therefore, the SPA-MLR method risks the loss of useful information. To make a full use of the useful information in the spectra, a new method named “consensus SPA-MLR” (C-SPA-MLR) is proposed herein. This method is the combination of consensus strategy and SPA-MLR method. In the C-SPA-MLR method, SPA-MLR is used to construct member models with different subsets of variables, which are selected from the remaining variables iteratively. A consensus prediction is obtained by combining the predictions of the member models. The proposed method is evaluated by analyzing the near infrared (NIR) spectra of corn and diesel. The results of C-SPA-MLR method showed a better prediction performance compared with the SPA-MLR and full-spectra PLS methods. Moreover, these results could serve as a reference for combination the consensus strategy and other variable selection methods when analyzing NIR spectra and other spectroscopic techniques. 相似文献
39.
Ngoc Hai Trinh 《Optimization》2017,66(3):381-396
In this paper, we introduce a new definition of Lipschitz-type continuity of a bifunction. Using this definition, we prove the contraction of the proximal mapping and apply it to the equilibrium problem over the fixed-point set of a nonexpansive mapping. We present a new algorithm for this problem. Under classical conditions, the convergence of the algorithm is proved. Finally, we present some numerical results for the proposed algorithm. 相似文献
40.