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841.
Peter Poelt 《Mikrochimica acta》2000,132(2-4):129-135
Use of the L-lines in connection with the elements of the first transition series entails a lot of problems. The corresponding
X-ray peaks are composed of contributions of a group of several lines. Because of the incompletely filled 3d-shells, the intensity
ratios of the lines and thus the overall peak shapes of the X-ray peaks vary with the type of bonding of the respective element.
A special problem posed is that of high energy satellites, which could be strongly absorbed even by use of low electron energies.
Crucial for reliable quantitative results is a careful choice of reference spectra for peak deconvolution and peak fit.
Nevertheless, with appropriate care results with an accuracy of around 10–15 wt% relative may be obtained. This has been tested
by performing quantitative analysis on a haematite and magnetite specimen by use of the Fe-L lines. 相似文献
842.
本文研究了一类多分子生化反应模型Dx=δ-ax-x^py^p,Dy=x^py^p-by当a≠0,p=3,q=2的情形,得出了不存在闭轨的参数区域;至少分支出两个极限环的参数区域以及极限的唯一性的参数区域的一些结果。 相似文献
843.
混沌时序相空间重构的分析和应用研究 总被引:7,自引:1,他引:6
在国内外学者工作的基出上,应用Legendere坐标法重构动力系统的相空间,研究了时序时隔τ的取值范围,讨论了时序间隔τ对相空间重构工作的影响,并用所提方法重构了系统的吸引子.算例表明所提方法是有效的. 相似文献
844.
半平面上的无限级随机Dirichlet级数的值分布 总被引:14,自引:4,他引:10
田范基 《数学物理学报(A辑)》2000,20(2):278-287
本文通过 Dirichlet级数增长性研究结果改进 ,以及对独立随机变量列 { Zn} ,在条件 EZn=0 , 正数α>0 ,使得 ,0 相似文献
845.
Jürgen Müller 《Numerical Algorithms》2000,24(3):299-308
Based on a continuity property of the Hadamard product of power series we derive results concerning the rate of convergence
of the partial sums of certain polynomial series expansions for Bessel functions. Since these partial sums are easily computable
by recursion and since cancellation problems are considerably reduced compared to the corresponding Taylor sections, the expansions
may be attractive for numerical purposes. A similar method yields results on series expansions for confluent hypergeometric
functions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
846.
Pamela B. Pierce Daniel Waterman 《Proceedings of the American Mathematical Society》2000,128(9):2593-2596
It is shown that the concept of bounded variation in the mean is not a meaningful generalization of ordinary bounded variation. In fact, it is a characterization of functions which differ from functions of bounded variation on a zero set.
847.
In this paper we have given transformations for the partial mock theta functions of order five and also some identities between these partial mock theta functions analogous to the identities given by Ramanujan. 相似文献
848.
We consider the development of a competing risks system following a two-stage stopping rule. This stopping procedure takes into account a desired probability of successfully completing an assigned task. Upon termination, the asymptotic properties of the estimator of the system reliability, as well as the stopping time variable, are examined. Moreover, the asymptotic risk associated with the two-stage procedure is presented. This risk is anchored on a loss function that considers losses incurred in not attaining the desired reliability and that of excessive testing. 相似文献
849.
Chaotic time series prediction using fuzzy sigmoid kernel-based support vector machines 总被引:1,自引:0,他引:1
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Support vector machines (SVM) have been widely used in chaotic time series
predictions in recent years. In order to enhance the prediction efficiency
of this method and implement it in hardware, the sigmoid kernel in SVM is
drawn in a more natural way by using the fuzzy logic method proposed in this
paper. This method provides easy hardware implementation and straightforward
interpretability. Experiments on two typical chaotic time series predictions
have been carried out and the obtained results show that the average CPU
time can be reduced significantly at the cost of a small decrease in
prediction accuracy, which is favourable for the hardware implementation for
chaotic time series prediction. 相似文献
850.
Approximate direct reduction method: infinite series reductions to the perturbed mKdV equation
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The approximate direct reduction method is applied to the perturbed mKdV
equation with weak fourth order dispersion and weak dissipation. The
similarity reduction solutions of different orders conform to formal
coherence, accounting for infinite series reduction solutions to the
original equation and general formulas of similarity reduction
equations. Painlevé II type equations, hyperbolic secant and
Jacobi elliptic function solutions are obtained for zero-order
similarity reduction equations. Higher order similarity reduction
equations are linear variable coefficient ordinary differential
equations. 相似文献