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101.
Josef Bukac 《逼近论及其应用》2008,(4):330-335
Minimization of the weighted nonlinear sum of squares of differences may be converted to the minimization of sum of squares. The Gauss-Newton method is recalled and the length of the step of the steepest descent method is determined by substituting the steepest descent direction in the Gauss-Newton formula. The existence of minimum is shown. 相似文献
102.
In this paper, general conditions of state classification for the total weighted occupation times of a class of infinitely
divisible superprocesses on a bounded domain D in ℝ
d
are given. As an application, some sufficient and necessary conditions are found for the total weighted occupation times
of some special superprocesses on D to be absolutely continuous or singular with respect to the Lebesgue measure on D.
The research of Yan-Xia Ren is supported by NNSF of China (Grant No. 10471003) and Foundation for Authors Awarded Excellent
Ph.D. Dissertation. 相似文献
103.
基于小子样的思想,探讨扭力轴表面缺陷对其疲劳寿命的影响,有助于进一步找到降低扭力轴表面凹坑对扭力轴疲劳寿命影响的方法. 相似文献
104.
Summary The aim of this paper is to propose new selection criteria for the orders of selfexciting threshold autoregressive (SETAR)
models. These criteria use bootstrap methodology; they are based on a weighted mean of the apparent error rate in the sample
and the average error rate obtained from bootstrap samples not containing the point being predicted. These new criteria are
compared with the traditional ones based on the Akaike information criterion (AIC). A simulation study and an example on a
real data set end the paper. 相似文献
105.
岑建苗 《浙江大学学报(理学版)》2005,32(6):601-604,610
利用态射的加权广义逆,引进并讨论态射集中的加权减序和加权星序.给出了态射集中的加权减序的一些刻画和性质以及加权减序和加权星序之间的关系.加权减序和加权星序都是态射集中的新的偏序.所得结果均可应用于矩阵理论中.
关键词:态射;加权广义逆;加权减序;加权星序 相似文献
106.
Most writers on frequency assignment algorithms have described the details of a single algorithm, and evaluated the algorithm on selected data sets. There has been relatively little emphasis on describing the common features that are important if an algorithm is to have good performance. This paper describes the key features, with particular emphasis on algorithms for weighted fixed spectrum problems. The use of algorithms handling weighted constraints has become increasingly common in recent years. The advantages and disadvantages of weighting constraints are demonstrated. 相似文献
107.
令T是以{Wk}∞k=1B(Cn)为权序列的内射算子权移位.设T是强不可约的,而且sup1k<∞‖W-1k‖< ∞.用A′(T)表示T的换位代数,radA′(T)表示A′(T)的Jacobson根.本文刻划了radA′(T)并且证明了商代数A′(T)/radA′(T)是交换的. 相似文献
108.
Mahdi Zarghami Ferenc Szidarovszky Reza Ardakanian 《Fuzzy Optimization and Decision Making》2008,7(1):1-15
All realistic Multi-Criteria Decision Making (MCDM) problems face various kinds of uncertainty. Since the evaluations of alternatives
with respect to the criteria are uncertain they will be assumed to have stochastic nature. To obtain the uncertain optimism
degree of the decision maker fuzzy linguistic quantifiers will be used. Then a new approach for fuzzy-stochastic modeling
of MCDM problems will be introduced by merging the stochastic and fuzzy approaches into the OWA operator. The results of the
new approach, entitled FSOWA, give the expected value and the variance of the combined goodness measure for each alternative.
Robust decision depends on the combined goodness measures of alternatives and also on the variations of these measures under
uncertainty. In order to combine these two characteristics a composite goodness measure will be defined. The theoretical results
will be illustrated in a watershed management problem. By using this measure will give more sensitive decisions to the stakeholders
whose optimism degrees are different than that of the decision maker. FSOWA can be used for robust decision making on the
competitive alternatives under uncertainty. 相似文献
109.
本文研究两两NQD系加权和的完全收敛性,证明了一般双下标加权系数的加权部分和的完全收敛性,改进了吴群英(2002)的结果。 相似文献
110.
陈辉 《新疆大学学报(理工版)》2008,25(1):50-54
讨论了一类带有粗糙核的Marcinkiewicz积分算子在加权Herz空间上的有界性. 相似文献