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101.
用单调迭代方法给出了二阶常微分方程初值问题的解的存在唯一性的结果. 相似文献
102.
103.
An automatic monitoring and intervention algorithm that permits the supervision of very general aspects in an univariate linear Gaussian state–space model is proposed. The algorithm makes use of a model comparison and selection approach within a Bayesian framework. In addition, this algorithm incorporates the possibility of eliminating earlier interventions when subsequent evidence against them comes to light. Finally, the procedure is illustrated with two empirical examples taken from the literature. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
104.
Agnieszka Ka&#x;amajska 《Mathematical Methods in the Applied Sciences》2006,29(11):1307-1325
The weak limits of sequences {f(uν)}ν∈? where uν's are vector‐valued µ‐measurable functions defined on a compact set Ω and f is (possibly) discontinuous are investigated. As shown by the author (J. Conv. Anal. (to appear)), they are described in terms of integral formulae involving parametrized measures independent of f, similarly as in the classical theorem by Young and its generalization due to DiPerna and Majda. In the present paper we describe the supports of the involved parametrized measures. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
105.
Zhijian Wu 《Frontiers of Mathematics in China》2007,2(2):287-303
We characterize the symbol functions so that the associated commutators with symbol functions and the Hilbert transform are bounded on Lipschitz space Λ α p , where 1 < p < ∞ and 0 < α < 1/p. Properties of such symbols are also discussed. 相似文献
106.
M. S. Finkelstein 《商业与工业应用随机模型》2003,19(2):133-146
A number of conventional measures of risk as real‐valued functions on the space of positive random variables are considered: the expected shortfall, the mean excess over the threshold, the stop‐loss and some others. Ordering of risks, based on these measures and the distances between corresponding distribution functions, are described. The perturbed measures, describing the effect of changing environment, are discussed. These measures are defined by the accelerated life and proportional hazards models widely used in reliability and survival analysis. The case of a random environment is of a prime interest in the paper. The main result states that if, for instance, the stochastic environment is ‘neutral in expectation’ with respect to the baseline one, the distance between the corresponding distribution functions can be still sufficiently large. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
107.
What features characterize complex system dynamics? Power laws and scale invariance of fluctuations are often taken as the hallmarks of complexity, drawing on analogies with equilibrium critical phenomena. Here we argue that slow, directed dynamics, during which the system's properties change significantly, is fundamental. The underlying dynamics is related to a slow, decelerating but spasmodic release of an intrinsic strain or tension. Time series of a number of appropriate observables can be analyzed to confirm this effect. The strain arises from local frustration. As the strain is released through “quakes,” some system variable undergoes record statistics with accompanying log‐Poisson statistics for the quake event times. We demonstrate these phenomena via two very different systems: a model of magnetic relaxation in type II superconductors and the Tangled Nature model of evolutionary ecology and show how quantitative indications of aging can be found. © 2004 Wiley Periodicals, Inc. Complexity 10: 49–56, 2004 相似文献
108.
Chao Liu Chuandong Li Tingwen Huang Hui Wang 《Mathematical Methods in the Applied Sciences》2015,38(14):2922-2936
This paper focuses on the stability in terms of two measures for functional differential equation with variable‐time impulses. Being different from most of existing literatures, the impulses of functional differential equation are assumed to be closely associated to the current state. We propose a new comparison principle for the considered systems and establish several stability criteria in terms of two measures. Also, the theoretical results are applied in a class of delayed neural network systems with variable‐tine impulses, and numerical simulations are introduced to illustrate the effectiveness of our results. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
109.
设$mu_{M,D}$是由仿射迭代函数系${phi_{d}(x)=M^{-1}(x+d)}_{din D}$唯一确定的自仿测度,它的谱与非谱性质与Hilbert空间$L^{2}(mu_{M,D})$中正交指数函数系的有限性和无限性有着直接的关系.本文将利用矩阵的初等变换给出$mu_{M,D}$,{-}!!正交指数函数系有限性的一个充分条件. 由于这个条件只与矩阵$M$的行列式有关, 因此, 它在$mu_{M,D}$的非谱性的判断方面便于直接验证. 相似文献
110.