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31.
利用推广的二阶拟Newton方程,提出了一种推广的对角二阶拟柯西算法,在新算法中引入了参数θ,使得对角二阶拟柯西法可以推广到更大的范围.并且证明了在一定的条件下新算法的全局收敛和超线性收敛.最后通过数值试验说明了新算法是有效可行的. 相似文献
33.
Starting from the notion of h-type indices for infinite sequences we investigate if these indices satisfy natural inequalities related to the arithmetic, the geometric and the harmonic mean. If f denotes an h-type index, such as the h- or the g-index, then we investigate inequalities such as min(f(X),f(Y)) ≤ f((X?+?Y)/2) ≤ max(f(X), f(Y)). We further investigate if: f(min(X,Y)) = min(f(X),f(Y)) and if f(max(X,Y)) = max(f(X),f(Y)). It is shown that the h-index satisfies all the equalities and inequalities we investigate but the g-index does not always, while it is always possible to find a counterexample involving the R-index. This shows that the h-index enjoys a number of interesting mathematical properties as an operator in the partially ordered positive cone (R+)∞ of all infinite sequences with non-negative real values.In a second part we consider decreasing vectors X and Y with components at most at distance d. Denoting by D the constant sequence (d,d,d, …) and by Y-D the vector (max(yr-d), 0)r, we prove that under certain natural conditions, the double inequality h(Y-D) ≤ h(X) ≤ h(Y?+?D) holds. 相似文献
34.
Neil Sheldon 《Teaching Statistics》2004,26(1):24-25
This article defines the generalized mean and shows how it relates to such statistics as the arithmetic, geometric and harmonic means. 相似文献
35.
亏损矩阵的乘法可交换及其可传递的条件 总被引:1,自引:0,他引:1
李大林 《桂林师范高等专科学校学报》2003,17(1):93-96
定义了广义0-若当块及其广义幂,并以它们为工具,探讨了亏损矩阵的乘法可交换条件及其可传递的条件。 相似文献
36.
首先将广义准循环码的概念推广到环Z2k1+上,然后仿照Fq上广义准循环码的生成元的形式,给出了环Z2k1+上的1-生成元广义准循环码C的生成元的具体形式,最后通过给出C为Z2k1+自由模的充分条件,得出C为自由模时码C的维数及最小距离. 相似文献
37.
38.
本文在Hauscloff拓扑向量空间中引入和研究了一类广义多值向量变分不等式问题,通过运用删定理证明了解的一些存在性定理,推广和改进了文献[3][5]的相关研究成果. 相似文献
39.
The measurement of teaching efficiency of Italian universities has become a topic of much interest and debate in recent years. The aim of this study is to fully explore the potential of panel data in the analysis of teaching efficiency both by modelling human capital formation in the university as a series of sub-processes and by using various models to account for observed and unobserved factors which generate heterogeneity. The new approach for estimating a stochastic frontier model based on the Generalized Maximum Entropy method provides further insights into the measurement of university teaching performance. The evolution of efficiency throughout the entire study period was also analyzed. 相似文献
40.
《Journal of Informetrics》2019,13(3):785-792
In this article we solve a minimum problem involving step functions. The solution of this problem leads to an investigation into generalized h- and g-indices. This minimum problem and the related generalized h- and g-indices are studied in a general context of decreasing differentiable functions as well as in the specific case of Lotkaian informetrics. The study illustrates the use of h-and g-indices and their generalizations in a context which bears no relation to the research evaluation context in which these indices were originally introduced. 相似文献