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911.
In this paper we study nonlinear quasistatic problems from inelastic deformations theory. Only strictly monotone, gradient-type constitutive equations are considered. We prove existence for both coercive and non-coercive models, using energy estimates and Young measures. For non-coercive models we use the L2 self-controlling property.  相似文献   
912.
We prove that for every M,NN, if τ is a Borel, finite, absolutely friendly measure supported on a compact subset K of RMN, then KBA(M,N) is a winning set in Schmidt's game sense played on K, where BA(M,N) is the set of badly approximable M×N matrices. As an immediate consequence we have the following application. If K is the attractor of an irreducible finite family of contracting similarity maps of RMN satisfying the open set condition (the Cantor's ternary set, Koch's curve and Sierpinski's gasket to name a few known examples), then
dimK=dimKBA(M,N).  相似文献   
913.
914.
The paper considers a particular family of fuzzy monotone set-valued stochastic processes. The proposed setting allows us to investigate suitable α-level sets of such processes, modeling birth-and-growth processes. A decomposition theorem is established to characterize the nucleation and the growth. As a consequence, different consistent set-valued estimators are studied for growth process. Moreover, the nucleation process is studied via the hitting function, and a consistent estimator of the nucleation hitting function is derived.  相似文献   
915.
Let (X, d) be a compact metric space and let (X) denote the space of all finite signed Borel measures on X. Define I: (X) → ℝ by I(μ) = ∫ X X d(x, y)dμ(x)dμ(y), and set M(X) = sup I(μ), where μ ranges over the collection of measures in (X) of total mass 1. The space (X, d) is quasihypermetric if I(μ) ≦ 0 for all measures μ in (X) of total mass 0 and is strictly quasihypermetric if in addition the equality I(μ) = 0 holds amongst measures μ of mass 0 only for the zero measure. This paper explores the constant M(X) and other geometric aspects of X in the case when the space X is finite, focusing first on the significance of the maximal strictly quasihypermetric subspaces of a given finite quasihypermetric space and second on the class of finite metric spaces which are L 1-embeddable. While most of the results are for finite spaces, several apply also in the general compact case. The analysis builds upon earlier more general work of the authors [11] [13].   相似文献   
916.
The paper introduces a new risk measure called Conditional Average (CAVG), which was designed to cover typical attitudes towards risk for any type of distribution. It can be viewed as a generalization of Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR), two commonly used risk measures. The preference structure induced by CAVG has the interpretation in Yaari’s dual theory of choice under risk and relates to Tversky and Kahneman’s cumulative prospect theory. The measure is based on the new stochastic ordering called dual prospect stochastic dominance, which can be considered as a dual stochastic ordering to recently developed prospect stochastic dominance. In general, CAVG translates into a nonconvex quadratic programming problem, but in the case of a finite probability space it can also be expressed as a mixed-integer program. The paper also presents the results of computational studies designed to assess the preference modeling capabilities of the measure. The experimental analysis was performed on the asset allocation problem built on historical values of S&P 500 sub-industry indexes. The research was supported by the grant PBZ-KBN-016/P03/99 from the State Committee for Scientific Research.  相似文献   
917.
为考察环境审计在节能减排中的规制效果,本文设计了两个参与人三种情境下的博弈模型,(1)监管者介入公司环境审计报告、无条件处罚,(2)监管者不介入公司环境审计报告、无条件处罚,(3)监管者介入公司环境审计报告,有条件处罚。研究结果表明,审计报告的介入权为公司开展环境审计提供了正向激励;公司因努力改善环境而减轻处罚的有条件处罚机制增加了公司环境审计的倾向性。本文的研究发现为环境审计制度设计提供了理论基础。  相似文献   
918.
In this article, we first prove the existence of the pullback attractor for no-autonomous discrete Klein-Gordon-Schrodinger-type equations. Then we construct the invariant measure and statistical solutions for this discrete equations via the generalized Banach limit.  相似文献   
919.
Some recent developments in the analysis of long-time behaviors of stochastic solutions of nonlinear conservation laws driven by stochastic forcing are surveyed. The existence and uniqueness of invariant measures are established for anisotropic degenerate parabolic-hyperbolic conservation laws of second-order driven by white noises. Some further developments, problems, and challenges in this direction are also discussed.  相似文献   
920.
A finite Borel measure μ in Rd is called a frame-spectral measure if it admits an exponential frame (or Fourier frame) for L2(μ). It has been conjectured that a frame-spectral measure must be translationally absolutely continuous, which is a criterion describing the local uniformity of a measure on its support. In this paper, we show that if any measures ν and λ without atoms whose supports form a packing pair, then ν?λ+δt?ν is translationally singular and it does not admit any Fourier frame. In particular, we show that the sum of one-fourth and one-sixteenth Cantor measure μ4+μ16 does not admit any Fourier frame. We also interpolate the mixed-type frame-spectral measures studied by Lev and the measure we studied. In doing so, we demonstrate a discontinuity behavior: For any anticlockwise rotation mapping Rθ with θ±π/2, the two-dimensional measure ρθ(?):=(μ4×δ0)(?)+(δ0×μ16)(Rθ?1?), supported on the union of x-axis and y=(cot?θ)x, always admit a Fourier frame. Furthermore, we can find {e2πiλ,x}λΛθ such that it forms a Fourier frame for ρθ with frame bounds independent of θ. Nonetheless, ρ±π/2 does not admit any Fourier frame.  相似文献   
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