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71.
This article concerns the antisymmetry, uniqueness, and monotonicity properties of solutions to some elliptic functionals involving weights and a double well potential. In the one-dimensional case, we introduce the continuous odd rearrangement of an increasing function and we show that it decreases the energy functional when the weights satisfy a certain convexity-type hypothesis. This leads to the antisymmetry or oddness of increasing solutions (and not only of minimizers). We also prove a uniqueness result (which leads to antisymmetry) where a convexity-type condition by Berestycki and Nirenberg on the weights is improved to a monotonicity condition. In addition, we provide with a large class of problems where antisymmetry does not hold. Finally, some rather partial extensions in higher dimensions are also given. 相似文献
72.
《Annals of Pure and Applied Logic》2020,171(2):102756
We define and investigate a uniformly locally o-minimal structure of the second kind in this paper. All uniformly locally o-minimal structures of the second kind have local monotonicity, which is a local version of monotonicity theorem of o-minimal structures. We also demonstrate a local definable cell decomposition theorem for definably complete uniformly locally o-minimal structures of the second kind. We define dimension of a definable set and investigate its basic properties when the given structure is a locally o-minimal structure which admits local definable cell decomposition. 相似文献
73.
Siegmund Duality for Continuous Time Markov Chains on ℤ<Stack><Subscript>+</Subscript><Superscript>d</Superscript></Stack>
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Pan Zhao 《数学学报(英文版)》2018,34(9):1460-1472
For the continuous time Markov chain with transition function P(t) on Z+d, we give the necessary and sufficient conditions for the existence of its Siegmund dual with transition function P(t). If Q, the q-matrix of P(t), is uniformly bounded, we show that the Siegmund dual relation can be expressed directly in terms of q-matrices, and a sufficient condition under which the Q-function is the Siegmund dual of some Q-function is also given. 相似文献
74.
用在线梯度法训练积单元神经网络的收敛性分析 总被引:1,自引:0,他引:1
<正>1引言仅由加和单元构成的传统前向神经网络已经广泛应用于模式识别及函数逼近等领域.但在处理比较复杂的问题时,这种网络往往需要补充大量的隐节点,这样就不可避免地增 相似文献
75.
研究函数方程组I(x,T(y,z))=T(I(x,y),I(x,z)),I(x,y)=I(N(y),N(x))的解,其中T:[0,1]2→[0,1]是一个严格三角模,I:[0,1]2→[0,1]是一个模糊蕴涵算子和N:[0,1]→[0,1]是一个强否定.在I除了在点(0,0),(1,1)不连续的假设下,获得了满足这个函数方程组解的完全刻画. 相似文献
76.
The psi function ψ(x) is defined by ψ(x)=Γ′(x)/Γ(x), where Γ(x) is the gamma function. We give necessary and sufficient conditions for the function ψ″(x)+[ψ′(x+α)]2 or its negative to be completely monotonic on (−α,∞), where . We also prove that the function [ψ′(x)]2+λψ″(x) is completely monotonic on (0,∞) if and only if λ1. As an application of the latter conclusion, the monotonicity and convexity of the function epψ(x+1)−qx with respect to x(−1,∞) are thoroughly discussed for p≠0 and . 相似文献
77.
M. Chrif 《Applicable analysis》2013,92(7):865-871
78.
In this work, we study the existence of C n -almost periodic solutions and C n -almost automorphic solutions (n?≥?1), for partial neutral functional differential equations. We prove that the existence of a bounded integral solution on ?+ implies the existence of C n -almost periodic and C n -almost automorphic strict solutions. When the exponential dichotomy holds for the homogeneous linear equation, we show the uniqueness of C n -almost periodic and C n -almost automorphic strict solutions. 相似文献
79.
80.
Emil Daniel Schwab 《代数通讯》2013,41(5):1779-1789
We study the incidence algebra of the reduced standard division category of a combinatorial bisimple inverse monoid [with (E(S), ≤) locally finite], and we describe semigroups of poset type (i.e., a combinatorial inverse semigroup for which the corresponding Möbius category is a poset) as being combinatorial strict inverse semigroups. Up to isomorphism, the only Möbius-division categories are the reduced standard division categories of combinatorial inverse monoids. 相似文献