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71.
The convergence (X
n, Yn)0 is investigated and characterized for probability metrics which metrize convergence in distribution or in probability. Some related metrics are also considered. 相似文献
72.
Fujita S 《Chemical record (New York, N.Y.)》2002,2(3):164-176
The concept of sphericity and relevant fundamental concepts that we have proposed have produced a systematized format for comprehending stereochemical phenomena. Permutability of ligands in conventional approaches is discussed from a stereochemical point of view. After the introduction of orbits governed by coset representations, the concepts of subduction and sphericity are proposed to characterize desymmetrization processes, with a tetrahedral skeleton as an example. The stereochemistry and stereoisomerism of the resulting promolecules (molecules formulated abstractly) are discussed in terms of the concept of sphericity as a common mathematical and logical framework. Thus, these promolecules are characterized by point group and permutation group symmetry. Prochirality, stereogenicity, prostereogenicity, and relevant topics are described in terms of the concept of sphericity. 相似文献
73.
Both the spectra and infrared transition strengths of C6H6 and C6D6 for the C? H stretching overtones up to as high as v = 10 are described in high precision with few parameters (six for the spectra and four for the transition strengths) by the Iachello–Oss algebraic model. The Hamiltonian model is solved in the symmetry adapted bases, which are constructed by the symmetrized boson representation (SBR) technique. The results show that the combination of the algebraic method and SBR technique is a powerful method for describing vibrations of large molecules and high overtones. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
74.
Factor analysis is a powerful tool used for the analysis of dynamic studies. One of the major drawbacks of Factor Analysis of Dynamic Structures (FADS) is that the solution is not mathematically unique when only non-negativity constraints are used to determine factors and factor coefficients. In this paper, we introduce a novel method to correct FADS solutions by constructing and minimizing a new objective function. The method is improved from non-negative matrix factorizations (NMFs) algorithm by adding a sparse constraint that penalizes multiple components in the images of the factor coefficients. The technique is tested on computer simulations, and a patient ultrasound liver study. The results show that the method works well in comparison to the truth in computer simulations and to region of interest (ROI) measurements in the experimental studies. 相似文献
75.
76.
Yushuang Li Yufang Qin Xiaoqi Zheng Yu Zhang 《International journal of quantum chemistry》2012,112(10):2330-2335
A new three‐dimensional graphical representation of DNA sequences, three‐unit semicircles (TUS)‐curve, which maps a given sequence into a dot sequences embedded in three‐unit semicircles, is proposed based on three biclassifications of nucleotides. TUS‐curve has the merit of compactness and could avoid the degeneracy and loss of information. The geometrical center of the curve, which indicates the distribution of base frequencies of the corresponding DNA sequence, is extracted and applied to analyze the similarity of various species. Phylogenetic tree of 11 species based on their first exons of β‐globin genes showed that the TUS‐curve is a powerful tool to get valuable biological information. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
77.
Z. Šikić 《International Journal of Mathematical Education in Science & Technology》2013,44(6):923-927
By stretching the area under the curve x α it is shown to be of the form x α + 1 p(α). Geometry is then used to prove p(α) = 1/(α + 1). 相似文献
78.
LI YuQiang 《中国科学 数学(英文版)》2014,(10)
We consider a kind of site-dependent branching Brownian motions whose branching laws depend on the site-branching factorσ(·).We focus on the functional ergodic limits for the occupation time processes of the models in R.It is proved that the limiting process has the form ofλξ(·),where A is the Lebesgue measure on IE andξ(·)is a real-valued process which is non-degenerate if and only ifσis integrable.Whenξ(·)is non-degenerate,it is strictly positive for t0.Moreover,ξconverges to O in finite-dimensional distributions if the integral ofσtends to infinity. 相似文献
79.
Zhao-Long Hu Zhesi Shen Chang-Bing Tang Bin-Bin Xie Jian-Feng Lu 《Physics letters. A》2018,382(14):931-937
Locating sources in a large network is of paramount importance to reduce the spreading of disruptive behavior. Based on the backward diffusion-based method and integer programming, we propose an efficient approach to locate sources in complex networks with limited observers. The results on model networks and empirical networks demonstrate that, for a certain fraction of observers, the accuracy of our method for source localization will improve as the increase of network size. Besides, compared with the previous method (the maximum–minimum method), the performance of our method is much better with a small fraction of observers, especially in heterogeneous networks. Furthermore, our method is more robust against noise environments and strategies of choosing observers. 相似文献
80.
This paper deals with predictable representation in continuous trading. First of all we give a positive answer to a conjecture of Harrison and Pliska [2]. Then we prove the completeness of a model of mixed type (see[2]). A slight modificationof this example shows that the continuous and purely discontinuous parts of a local martingale depend on the filtration. 相似文献