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321.
本文在完备凸度量空间中,利用集值和单值映象(次)相容的一些条件,建立了数值广义非扩张映象存在公共不动点的一个充要条件和一个充分条件.我们的结果改进、扩充和发展了文[2~7]中的主要结果.  相似文献   
322.
This article provides a detailed comparison between two systems of collapsing functions. These functions play a crucial role in proof theory, in the analysis of patterns of resemblance, and the analysis of maximal order types of well partial orders. The exact correspondence given here serves as a starting point for far reaching extensions of current results on patterns and well partial orders. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim  相似文献   
323.
We show that many countable support iterations of proper forcings preserve Souslin trees. We establish sufficient conditions in terms of games and we draw connections to other preservation properties. We present a proof of preservation properties in countable support iterations in the so-called Case A that does not need a division into forcings that add reals and those who do not.  相似文献   
324.
Actuarial risks and financial asset returns are typically heavy tailed. In this paper, we introduce 2 stochastic dominance criteria, called the right‐tail order and the left‐tail order, to compare these variables stochastically. The criteria are based on comparisons of expected utilities, for 2 classes of utility functions that give more weight to the right or the left tail (depending on the context) of the distributions. We study their properties, applications, and connections with other classical criteria, including the increasing convex and the second‐order stochastic dominance. Finally, we rank some parametric families of distributions and provide empirical evidence of the new stochastic dominance criteria with an example using real data.  相似文献   
325.
《Mathematische Nachrichten》2017,290(5-6):867-875
The present paper establishes a duality relation for the spectra of self‐affine measures. This is done under the condition of compatible pair and is motivated by a duality conjecture of Dutkay and Jorgensen on the spectrality of self‐affine measures. For the spectral self‐affine measure, we first obtain a structural property of spectra which indicates that one can get new spectra from old ones. We then establish a duality property for the spectra which confirms the conjecture in a certain case.  相似文献   
326.
从弹性薄板理论出发,将箱型结构分为六块相互约束的简支薄板。每一块板在板内承受任意局部荷载,在四边承受待定的分布弯矩。通过板与板的边界转角协调分析,求解出每块板四边所受的分布弯矩,从而得到任意荷载作用下箱型结构的解析解。  相似文献   
327.
It is proved that a finite group whose element order set is the same as that of an alternating group A 22 of degree 22 is isomorphic to A 22.  相似文献   
328.
The aim of this paper is to obtain new coincidence and common fixed point theorems by using Lipschitz-type conditions of hybrid maps (not necessarily continuous) on a metric space. As applications, we demonstrate the existence of common fixed points from the set of best approximations. Our work sets analogues, unifies and improves various known results existing in the literature.  相似文献   
329.
This article reviews the static and dynamic properties of spontaneous superstructures formed by electrons. Representations of such electronic crystals are charge density waves (CDW) and spin density waves in inorganic as well as organic low-dimensional materials. A special attention is paid to the collective effects in pinning and sliding of these superstructures, and the glassy properties at low temperature. Charge order and charge disproportionation which occur in organic materials resulting from correlation effects are analysed. Experiments under magnetic field, and more specifically field-induced CDWs are discussed. Properties of meso- and nanostructures of CDWs are also reviewed.  相似文献   
330.
A novel copolymer was synthesized by the radical polymerization of 2-methacryloyloxyethylphosphorylcholine, stearyl methacrylate, hydroxypropyl methacrylate and trimethoxysilylpropyl methacrylate. The polymer was characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. The crosslinkable coating was prepared by dip-coating 5 mg/ml solution in tetrahydrofuran onto glass substrate. A stable crosslinked coating was obtained after curing the coating at 90 °C for 9 h. Contact angle results indicated the possible reorganization of the surface amphiphilic molecule that interpreted the excellent biocompatibility revealed by the results of the platelet adhesion and plasma recalcification time. Rhodamine S was used as a model drug to prepare drug-containing coating at the same conditions. Drug-releasing curves fall into Fickian release mechanism and there exists efficient releasing amount of the drug until 60 h.  相似文献   
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