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61.
This paper proposes a new non-intrusive hybrid interval method using derivative information for the dynamic response analysis of nonlinear systems with uncertain-butbounded parameters and/or initial conditions. This method provides tighter solution ranges compared to the existing polynomial approximation interval methods. Interval arithmetic using the Chebyshev basis and interval arithmetic using the general form modified affine basis for polynomials are developed to obtain tighter bounds for interval computation.To further reduce the overestimation caused by the "wrapping effect" of interval arithmetic, the derivative information of dynamic responses is used to achieve exact solutions when the dynamic responses are monotonic with respect to all the uncertain variables. Finally, two typical numerical examples with nonlinearity are applied to demonstrate the effectiveness of the proposed hybrid interval method, in particular, its ability to effectively control the overestimation for specific timepoints. 相似文献
62.
不确定非线性动力系统的稳定性分析 总被引:2,自引:0,他引:2
本文讨论渐近稳定的非线性名义动力系统在非线性时变扰动下的鲁棒稳定性问题。应用Lyapunov稳定性定理及其推广定理得出了非线性动力系统鲁棒稳定的若干判别准则,并给邮了应用所得准则的实际算例。 相似文献
63.
Differences of Convex Compact Sets in the Space of Directed Sets. Part I: The Space of Directed Sets
A normed and partially ordered vector space of so-called directed sets is constructed, in which the convex cone of all nonempty convex compact sets in R
n
is embedded by a positively linear, order preserving and isometric embedding (with respect to a new metric stronger than the Hausdorff metric and equivalent to the Demyanov one). This space is a Banach and a Riesz space for all dimensions and a Banach lattice for n=1. The directed sets in R
n
are parametrized by normal directions and defined recursively with respect to the dimension n by the help of a support function and directed supporting faces of lower dimension prescribing the boundary. The operations (addition, subtraction, scalar multiplication) are defined by acting separately on the support function and recursively on the directed supporting faces. Generalized intervals introduced by Kaucher form the basis of this recursive approach. Visualizations of directed sets will be presented in the second part of the paper. 相似文献
64.
关于三分Cantor集的构造的一个基本性质及其应用 总被引:13,自引:0,他引:13
本文提出了三分 Cantor集的构造的一个基本性质 .作为应用 ,给出了计算三分 Cantor集的简明的初等的计算方法 ,另外还得到了一列有趣的对数不等式 相似文献
65.
Frédéric Gardi 《Discrete Mathematics》2007,307(22):2906-2908
In this note, a constructive proof that the classes of proper interval graphs and unit interval graphs coincide is given, a result originally established by Fred S. Roberts. Additionally, the proof yields a linear-time and space algorithm to compute a unit interval representation, given a proper interval graph as input. 相似文献
66.
一种基于区间数的证券组合投资模型与求解 总被引:1,自引:0,他引:1
林军 《数学的实践与认识》2007,37(23):1-7
提出了区间数的相对左偏度的定义.利用区间数的相对左偏度作为区间数下表达证券风险损失率的一种补充,能合理地反映风险损失率与预期收益率之间的相关关系.建立了一种新的证券组合投资区间数规划模型,将区间数规划模型转化为参数线性规划问题求解,使证券组合投资决策分析更加具有柔性.最后通过实例分析了该模型的应用价值. 相似文献
67.
均匀分布参数的无偏估计及其分布 总被引:1,自引:0,他引:1
讨论了均匀分布未知参数无偏估计量的分布密度,利用无偏估计量构造出一些新的样本函数,并且利用给出的样本函数推导出了未知参数的置信区间.所得到结果改善了现有的估计,易于计算. 相似文献
68.
On the selection of subdivision directions in interval branch-and-bound methods for global optimization 总被引:3,自引:0,他引:3
This paper investigates the influence of the interval subdivision selection rule on the convergence of interval branch-and-bound algorithms for global optimization. For the class of rules that allows convergence, we study the effects of the rules on a model algorithm with special list ordering. Four different rules are investigated in theory and in practice. A wide spectrum of test problems is used for numerical tests indicating that there are substantial differences between the rules with respect to the required CPU time, the number of function and derivative evaluations, and the necessary storage space. Two rules can provide considerable improvements in efficiency for our model algorithm.The work has been supported by the Grants OTKA 2879/1991, and MKM 414/1994. 相似文献
69.
利用一维Cotes公式及高维积分Cartesian积空间上的求积法则,将Cotes公式推广到了n维空间上,并给出了简单的误差估计.该公式具有比文[4],[5],[6]相关结果更小的误差和更高的收敛阶等优点. 相似文献
70.
V. V. Podinovski 《Computational Mathematics and Mathematical Physics》2008,48(11):1981-1998
Multicriteria decision-making problems under bounded (above, below, or from both sides) continuous or discrete criteria are considered. Methods for comparing variants of solutions using the information accumulated in the form of interval estimates of replacing the values of some criteria by the values of others (such replacements are called tradeoffs; in other words, this can be considered as a compensation of the deterioration of some criteria by improving the values of others) are proposed along with simple consistency conditions of such information. The issue of constructing the set of nondominated variants is discussed. 相似文献