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141.
We continue our study of the existence of convergent iterations in the presence of computational errors for a nonexpansive setvalued mapping. In a recent paper we have shown that if for any initial point, there exists a trajectory of a nonexpansive set-valued mapping attracted by a given set, then this property is stable under small perturbations of the mapping. In particular, we have shown there that for any initial point, there exists a trajectory with a subsequence which is attracted by the attractor. In the present paper we show, under certain mild additional assumptions, that for any initial point, there exists a trajectory such that, for any given positive e\epsilon, almost all of its elements belong to an e\epsilon-neighborhood of the attractor.  相似文献   
142.
We establish three theorems which show that most of the bounded holomorphic self-mappings of a star-shaped domain in a complex Banach space map it strictly inside itself. According to the Earle–Hamilton fixed point theorem, each such mapping has a unique fixed point.  相似文献   
143.
We study the convergence of an iterative algorithm for finding common fixed points of finitely many Bregman firmly nonexpansive operators in reflexive Banach spaces. Our algorithm is based on the concept of the so-called shrinking projection method and it takes into account possible computational errors. We establish a strong convergence theorem and then apply it to the solution of convex feasibility and equilibrium problems, and to finding zeroes of two different classes of nonlinear mappings.  相似文献   
144.
Oxynitride phosphor powders comprising of CaSi2O2N2 doped with Tb3+ were successfully synthesized using a high-temperature solid-state reaction method. The experimentally determined photoluminescence (PL) properties of the produced phosphors meet the requirements of 2D/3D plasma display panels (PDPs). In particular, under the excitation of vacuum ultraviolet (VUV) synchrotron radiation and ultraviolet (UV) irradiation, emission peaks corresponding to the 5D37FJ (J=6, 5, 4, 3) and 5D47FJ (J=6, 5, 4, 3) transitions of Tb3+ ions were recorded. Monitoring the 5D47F5 emission of Tb3+ at 545 nm, the excitation bands were assigned to the host-related absorption as well as the 4f–5d (fd) and the 4f–4f (ff) transitions of Tb3+. The produced phosphors can be efficiently excited at 147 nm, and have an adequately short decay time (τ1/10=1.14 ms).  相似文献   
145.
We show that to each asymptotic contraction T with a bounded orbit in a complete metric space X, there corresponds a unique point x * such that all the iterates of T converge to x *, uniformly on any bounded subset of X. If, in addition, some power of T is continuous at x *, then x * is a fixed point of T. Dedicated to Professor Felix E. Browder with admiration and respect  相似文献   
146.
We construct families of three-dimensional linear codes that attain the Griesmer bound and give a non-explicit construction of linear codes that are one away from the Griesmer bound. All these codes contain the all-1 codeword and are constructed from small multiple blocking sets in AG(2,q).  相似文献   
147.
    
Fast solvers performing on a regular grid are often used for problems in elasticity, in order to avoid expensive mesh generations. However, if overlaps between solid materials occur without any interactions, these might deteriorate the results, especially for the stresses. Therefore, we want to present an approach for developing numerical methods for contact problems on a regular mesh with the help of signed distance data and multi-material voxels. In this contribution we will focus on problems in linear elastostatics with contact between several different bodies. Finally, we present the results from a numerical test for the two dimensional Hertz problem, solved on a triangular regular mesh. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
148.
    
We examine an elliptic optimal control problem with control and state constraints in ℝ3. An improved error estimate of 𝒪(hs) with 3/4 ≤ s ≤ 1 − ε is proven for a discretisation involving piecewise constant functions for the control and piecewise linear for the state. The derived order of convergence is illustrated by a numerical example.https://doi.org/10.1051/m2an/2011076  相似文献   
149.
Using the Kobayashi distance, we first establish a version of the Denjoy–Wolff theorem for a bounded and strictly convex domain in ${{\mathbb{C}}^k}$ . Next, we prove analogous results for semigroups of holomorphic mappings and the resolvents of their generators. Finally, we obtain theorems of Denjoy–Wolff type for families of holomorphic retracts of the open unit ball in a complex, reflexive, and strictly convex Banach space.  相似文献   
150.
    
The family of Newmark and generalized α‐methods is extended to constrained mechanical systems by using simultaneous position and velocity stabilization as key ideas. In this way, the acceleration constraints need not be evaluated, and the overall algorithm is about as expensive as the application of a BDF method to the GGL‐stabilized equations of motion. Moreover, the RATTLE method of molecular dynamics is included as special case. A convergence analysis of the presented α‐RATTLE algorithm shows global second order in both position and velocity variables while the Lagrange multipliers are computed to first order accuracy. Additonally, the property of adjustable numerical dissipation carries over from the unconstrained case.  相似文献   
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