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政府行为的转变必先实现人的观念转变
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作者 钱振明 《中国行政管理》 CSSCI 北大核心 1995年第2期40-40,共1页
政府行为的转变必先实现人的观念转变钱振明政府行为模式,并不是政府自己所能选择的,它不仅客观地决定于整个社会经济关系,同时取决于历史文化传统和人们的价值观念。钱振明认为,与市场经济对政府行为的要求相适应,人们的观念需要... 政府行为的转变必先实现人的观念转变钱振明政府行为模式,并不是政府自己所能选择的,它不仅客观地决定于整个社会经济关系,同时取决于历史文化传统和人们的价值观念。钱振明认为,与市场经济对政府行为的要求相适应,人们的观念需要实现这样一些转变;用创新意识替代不... 展开更多
关键词 政府行为 人的观念 观念转 平均主义 变必 公平与效率兼顾 收入分配 创新意识 历史文化传统 社会经济关系
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“物极必反”、“物极必变(异)”辨谬——“以空为实”的诡论 被引量:1
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作者 黄展骥 《毕节学院学报(综合版)》 2010年第9期30-35,共6页
"物极必反"(P)是我国传统哲学中卓越的经典命题,影响深远。然而,由于P暗中用"反"之前一阶段来定义"极",因此犹如"乌鸦是黑色的"(Q)命题一样,是隐蔽的重言真句,进而犯"以空为实"谬误... "物极必反"(P)是我国传统哲学中卓越的经典命题,影响深远。然而,由于P暗中用"反"之前一阶段来定义"极",因此犹如"乌鸦是黑色的"(Q)命题一样,是隐蔽的重言真句,进而犯"以空为实"谬误,即表面有经验内容,甚至"无所不包",但实质几近"空无所指"。至于"质量互变(物极必变异)"(R)比P更为笼统,也有类似P的谬误。 展开更多
关键词 以空为实 物极 物极(异) 重言真句 日常语言学派
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命运:一个哲学范畴 被引量:3
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作者 王晓华 《江苏社会科学》 CSSCI 北大核心 2001年第3期74-79,共6页
本文将命运界定为哲学范畴 ,在个体的层面上对命运进行基本的生存论分析 :( 1 )已生 ,必变 ,将死 ( 2 )与他人共在 ( 3)孤独乃是个体的命运 ,而不可修复的缺陷乃是个体的类命运。通过对命运与类命运的分析 ,作者重新探讨了自由与界限、... 本文将命运界定为哲学范畴 ,在个体的层面上对命运进行基本的生存论分析 :( 1 )已生 ,必变 ,将死 ( 2 )与他人共在 ( 3)孤独乃是个体的命运 ,而不可修复的缺陷乃是个体的类命运。通过对命运与类命运的分析 ,作者重新探讨了自由与界限、自由与命运、自由与责任等一系列重大的哲学问题 ,提出了一些独特的理解 ,并试图为本体论意义上的《命运学》 展开更多
关键词 个体 超越性 命运 类命运 责任 已生 将死 孤独
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Residual elastic stress strain field and geometrically necessary dislocation density distribution around nano-indentation in TA15 titanium alloy 被引量:7
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作者 何东 朱景川 +3 位作者 来忠红 刘勇 杨夏炜 农智升 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期7-13,共7页
Nanoindentation and high resolution electron backscatter diffraction(EBSD) were combined to examine the elastic modulus and hardness of α and β phases,anisotropy in residual elastic stress strain fields and distri... Nanoindentation and high resolution electron backscatter diffraction(EBSD) were combined to examine the elastic modulus and hardness of α and β phases,anisotropy in residual elastic stress strain fields and distributions of geometrically necessary dislocation(GND) density around the indentations within TA15 titanium alloy.The nano-indention tests were conducted on α and β phases,respectively.The residual stress strain fields surrounding the indentation were calculated through crosscorrelation method from recorded patterns.The GND density distribution around the indentation was calculated based on the strain gradient theories to reveal the micro-mechanism of plastic deformation.The results indicate that the elastic modulus and hardness for α p hase are 129.05 GPas and 6.44 GPa,while for β phase,their values are 109.80 GPa and 4.29 GPa,respectively.The residual Mises stress distribution around the indentation is relatively heterogeneous and significantly influenced by neighboring soft β phase.The region with low residual stress around the indentation is accompanied with markedly high a type and prismatic-GND density. 展开更多
关键词 nano-hardness stress strain fields geometrically necessary dislocation NANOINDENTATION electron backscatter diffraction TA15 titanium alloy
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Effect of microvoids on microplasticity behavior of dual-phase titanium alloy under high cyclic loading(Ⅰ):Crystal plasticity analysis 被引量:3
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作者 Kai-di LI Xiao-ning HAN +2 位作者 Bin TANG Meng-qi ZHANG Jin-shan LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期513-523,共11页
A crystal plasticity finite element(CPFE)model was established and 2D simulations were carried out to study the relationship between microvoids and the microplasticity deformation behavior of the dual-phase titanium a... A crystal plasticity finite element(CPFE)model was established and 2D simulations were carried out to study the relationship between microvoids and the microplasticity deformation behavior of the dual-phase titanium alloy under high cyclic loading.Results show that geometrically necessary dislocations(GND)tend to accumulate around the microvoids,leading to an increment of average GND density.The influence of curvature in the tip plastic zone(TPZ)on GND density is greater than that of the size of the microvoid.As the curvature in TPZ and the size of the microvoid increase,the cumulative shear strain(CSS)in the primaryα,secondaryα,andβphases increases.Shear deformation in the prismatic slip system is dominant in the primaryαphase.As the distance between the microvoids increases,the interactive influence of the microvoids on the cumulative shear strain decreases. 展开更多
关键词 crystal plasticity dual-phase Ti alloy MICROVOIDS high cyclic loading cumulative shear strain geometrically necessary dislocation
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历史的天空——电视连续剧<三国演义>片尾歌
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作者 王健 谷建芬 《中国电视》 北大核心 1995年第3期66-66,共1页
关键词 三国演义 电视连续剧 片尾 天空 长江 前飞 变必 鼓角 古道 岁月
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Asymptotics for the Tail Probability of Random Sums with a Heavy-Tailed Random Number and Extended Negatively Dependent Summands 被引量:3
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作者 Fengyang CHENG Na LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第1期69-78,共10页
Let (X, Xk : k ≥ 1) be a sequence of extended negatively dependent random variables with a common distribution F satisfying EX 〉 0.Let τ be a nonnegative integer-valued random variable, independent of {X, Xk :... Let (X, Xk : k ≥ 1) be a sequence of extended negatively dependent random variables with a common distribution F satisfying EX 〉 0.Let τ be a nonnegative integer-valued random variable, independent of {X, Xk : k ≥ 1}. In this paper, the authors obtain the necessary and sufficient conditions for the random sums Sτ=∑n=1^τ Xn to have a consistently varying tail when the random number τ has a heavier tail than the summands, i.e.,P(X〉x)/P(τ〉x)→0 as x →∞. 展开更多
关键词 Asymptotic behavior Random sums Heavy-Tailed distribution
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Oscillation criteria for second order neutral dynamic equations of Emden-Fowler type with positive and negative coefficients on time scales 被引量:9
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作者 DENG XunHuan WANG QiRu ZHOU Zhan 《Science China Mathematics》 SCIE CSCD 2017年第1期113-132,共20页
We investigate oscillation of certain second order neutral dynamic equations of Emden-Fowler type with positive and negative coefficients. We use some different techniques and apply Riccati transformation to establish... We investigate oscillation of certain second order neutral dynamic equations of Emden-Fowler type with positive and negative coefficients. We use some different techniques and apply Riccati transformation to establish new oscillatory criteria which include two necessary and sufficient conditions. Moreover, we point out that how the power γ plays its role. Some interesting examples are given to illustrate the versatility of our results. 展开更多
关键词 neutral dynamic equations oscillation positive and negative coefficients Riccati transformation
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TOEPLITZ ALGEBRAS ON DISCRETE GROUPS AND THEIR NATURAL MORPHISMS
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作者 J.LORCH XUQINGXIANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2005年第1期143-152,共10页
Let G be a discrete group, E1 and E2 be two subsets of G with E1 () E2, and e ∈ E2. Denote by TE1 and TE2 the associated Toeplitz algebras. In this paper, it is proved that the natural morphism γE2,E1 from TE1 to TE... Let G be a discrete group, E1 and E2 be two subsets of G with E1 () E2, and e ∈ E2. Denote by TE1 and TE2 the associated Toeplitz algebras. In this paper, it is proved that the natural morphism γE2,E1 from TE1 to TE2 exists as a C*-morphism if and only if E2 is finitely covariant-lifted by E1. Based on this necessary and sufficient condition, some applications are made. 展开更多
关键词 Toeplitz algebra Natural C-morphism Finite covariant-lift
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ON INVARIANT CHECKING
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作者 ZHANG Zhihai KAPUR Deepak 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第3期470-482,共13页
Checking whether a given formula is an invariant at a given program location(especially,inside a loop) can be quite nontrivial even for simple loop programs,given that it is in general an undecidable property.This is ... Checking whether a given formula is an invariant at a given program location(especially,inside a loop) can be quite nontrivial even for simple loop programs,given that it is in general an undecidable property.This is especially the case if the given formula is not an inductive loop invariant,as most automated techniques can only check or generate inductive loop invariants.In this paper,conditions are identified on simple loops and formulas when this check can be performed automatically.A general theorem is proved which gives a necessary and sufficient condition for a formula to be an invariant under certain restrictions on a loop.As a byproduct of this analysis,a new kind of loop invariant inside the loop body,called inside-loop invariant,is proposed.Such an invariant is more general than an inductive loop invariant typically used in the Floyd-Hoare axiomatic approach to program verification.The use of such invariants for program debugging is explored;it is shown that such invariants can be more useful than traditional inductive loop invariants especially when one is interested in checking extreme/side conditions such as underflow,accessing array/collection data structures outside the range,divide by zero,etc. 展开更多
关键词 ASSERTION Floyd-Hoare logic INVARIANT invariant generation.
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Strong Convergence for Weighted Sums of Negatively Associated Arrays 被引量:2
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作者 Hanying LIANG Jingjing ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第2期273-288,共16页
Let {Xni} be an array of rowwise negatively associated random variables and Tnk=k∑i=1 i^a Xni for a ≥ -1, Snk =∑|i|≤k Ф(i/nη)1/nη Xni for η∈(0,1],where Ф is some function. The author studies necessary a... Let {Xni} be an array of rowwise negatively associated random variables and Tnk=k∑i=1 i^a Xni for a ≥ -1, Snk =∑|i|≤k Ф(i/nη)1/nη Xni for η∈(0,1],where Ф is some function. The author studies necessary and sufficient conditions of ∞∑n=1 AnP(max 1≤k≤n|Tnk|〉εBn)〈∞ and ∞∑n=1 CnP(max 0≤k≤mn|Snk|〉εDn)〈∞ for all ε 〉 0, where An, Bn, Cn and Dn are some positive constants, mn ∈ N with mn /nη →∞. The results of Lanzinger and Stadtmfiller in 2003 are extended from the i.i.d, case to the case of the negatively associated, not necessarily identically distributed random variables. Also, the result of Pruss in 2003 on independent variables reduces to a special case of the present paper; furthermore, the necessity part of his result is complemented. 展开更多
关键词 Tail probability Negatively associated random variable Weighted sum
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Some results on pointwise second-order necessary conditions for stochastic optimal controls 被引量:2
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作者 ZHANG HaiSen ZHANG Xu 《Science China Mathematics》 SCIE CSCD 2016年第2期227-238,共12页
The purpose of this paper is to derive some pointwise second-order necessary conditions for stochastic optimal controls in the general case that the control variable enters into both the drift and the diffusion terms.... The purpose of this paper is to derive some pointwise second-order necessary conditions for stochastic optimal controls in the general case that the control variable enters into both the drift and the diffusion terms.When the control region is convex, a pointwise second-order necessary condition for stochastic singular optimal controls in the classical sense is established; while when the control region is allowed to be nonconvex, we obtain a pointwise second-order necessary condition for stochastic singular optimal controls in the sense of Pontryagin-type maximum principle. It is found that, quite different from the first-order necessary conditions,the correction part of the solution to the second-order adjoint equation appears in the pointwise second-order necessary conditions whenever the diffusion term depends on the control variable, even if the control region is convex. 展开更多
关键词 stochastic optimal control needle variation Pontryagin-type maximum principle pointwisesecond-order necessary condition Malliavin calculus
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LINEAR ISOMETRIC NON-ANTICIPATIVETRANSFORMATIONS OF WIENER PROCESS
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作者 ZORAN IVKOVIC DRAZEN PANTIC 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2000年第1期109-114,共6页
The necessary and sufficient conditions are given so that a non-anticipative transformation in Hilbert space is isometric. In terms of second order Wiener process, these conditions assure that a non-anticipative trans... The necessary and sufficient conditions are given so that a non-anticipative transformation in Hilbert space is isometric. In terms of second order Wiener process, these conditions assure that a non-anticipative transformation of Wiener process is a Wiener process, too. 展开更多
关键词 Resolution of identity Separable Hilbert space Wide sense Wiener process Non-anticipative transformation
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ON CONTROLLABILITY FOR STOCHASTIC CONTROL SYSTEMS WHEN THE COEFFICIENT IS TIME-VARIANT 被引量:1
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作者 Feng LIU Shige PENG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第2期270-278,共9页
This paper investigates the controllability problem of time-variant linear stochastic controlsystems.A sufficient and necessary condition is established for stochastic exact controllability,whichprovides a useful alge... This paper investigates the controllability problem of time-variant linear stochastic controlsystems.A sufficient and necessary condition is established for stochastic exact controllability,whichprovides a useful algebraic criterion for stochastic control systems.Furthermore,when the stochasticsystems degenerate to deterministic systems,the algebraic criterion becomes the counterpart for thecomplete controllability of deterministic control systems. 展开更多
关键词 Backward stochastic differential equation (BSDE) E-well-posedness Stochastic controlsystem stochastic exact controllability.
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