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狭义相对论教学中不该出现的错误 被引量:7
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作者 张元仲 《物理与工程》 2017年第4期3-9,共7页
本文为了阐明个别大学物理教材中对光速不变假设的错误评论而详细说明了光速不变原理的两个用途:首要用途是用来定义惯性系中的时间坐标(即定义同时性);第二个用途是用来推导洛伦兹变换。随后,在分析了钟慢效应、尺缩效应、同时性的相... 本文为了阐明个别大学物理教材中对光速不变假设的错误评论而详细说明了光速不变原理的两个用途:首要用途是用来定义惯性系中的时间坐标(即定义同时性);第二个用途是用来推导洛伦兹变换。随后,在分析了钟慢效应、尺缩效应、同时性的相对性之后解释了尺缩佯谬,并特别指出了某大学物理教材中对一道习题提供的答案是错误的并用两种解法给出了正确答案。 展开更多
关键词 光速不变原理 相对性原理 洛伦兹变换 时钟变慢 尺子缩短 同时性的相对性
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS WITH NON-SEPARATED TYPE INTEGRAL BOUNDARY CONDITIONS 被引量:6
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作者 Bashir Ahmad Juan J. Nieto Ahmed Alsaedi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2122-2130,共9页
In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results a... In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2. 展开更多
关键词 fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree
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LOCAL INEQUALITIES FOR SIDON SUMS AND THEIR APPLICATIONS 被引量:1
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作者 范爱华 章逸平 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期305-316,共12页
The authors consider Sidon sets of first kind. By comparing them with the Steinhaus sequence, they prove a local Khintchine-Kahane inequality on compact sets. As consequences, they prove the following results for Sido... The authors consider Sidon sets of first kind. By comparing them with the Steinhaus sequence, they prove a local Khintchine-Kahane inequality on compact sets. As consequences, they prove the following results for Sidon series taking values in a Banach space: the summability on a set of positive measure implies the almost everywhere convergence; the contraction principle of Billard-Kahane remains true for Sidon series. As applications, they extend a uniqueness theorem of Zygmund concerning lacunary Fourier series and an analytic continuation theorem of Hadamard concerning lacunary Taylor series. Some of their results still hold for Sidon sets of second kind. 展开更多
关键词 Sidon set. Khintchine-Kahanc inequality maximal inequality comparison principle contraction principle
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STABILITY RESULTS OF RANDOM IMPULSIVE SEMILINEAR DIFFERENTIAL EQUATIONS 被引量:2
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作者 M.GOWRISANKAR P.MOHANKUMAR A.VINODKUMAR 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1055-1071,共17页
In this paper, we study the existence, uniqueness, continuous dependence, Ulam stabilities and exponential stability of random impulsive semilineax differential equations under sufficient condition. The results are ob... In this paper, we study the existence, uniqueness, continuous dependence, Ulam stabilities and exponential stability of random impulsive semilineax differential equations under sufficient condition. The results are obtained by using the contraction mapping principle. Finally an example is given to illustrate the applications of the abstract results. 展开更多
关键词 semilinear differential equations random impulses stability Hyers-Ulam stability Hyers-Ulam-Rassias stability exponential stability contraction principle
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Existence of Positive Solutions for a Third-Order Multi-Point Boundary Value Problem 被引量:2
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作者 A. Guezane-Lakoud L. Zenkoufi 《Applied Mathematics》 2012年第9期1008-1013,共6页
By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous ... By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous boundary value problem (BVP1): where for The interesting point lies in the fact that the nonlinear term is allowed to depend on the first order derivative . 展开更多
关键词 Guo’s Fixed POINT THEOREM Three POINT Boundary Value Problem Positive Solution LERAY SCHAUDER Non-Linear Alternative contraction principle
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爱因斯坦相对论的时空特性研究 被引量:3
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作者 张宁 《北京联合大学学报》 CAS 2005年第1期15-18,共4页
 时间和空间是相对论研究的重要物理问题,在物质的空间中,存在引力场,而由于引力场的存在,则会导致时间的变化,空间的弯曲,光线轨迹的改变等。对相对论中的时间和空间特性进行了探讨,分析了广义相对论中的等效原理和广义协变原理,讨论...  时间和空间是相对论研究的重要物理问题,在物质的空间中,存在引力场,而由于引力场的存在,则会导致时间的变化,空间的弯曲,光线轨迹的改变等。对相对论中的时间和空间特性进行了探讨,分析了广义相对论中的等效原理和广义协变原理,讨论了爱因斯坦引力场方程,研究了相对性原理、引力场中的时间膨胀、长度收缩和引力波。 展开更多
关键词 广义相对论 等效原理 引力场 时间膨胀 长度收缩 引力波
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运动的核弹比静止的核弹威力小?——多普勒效应、红移、光行差和动体的质能当量关系 被引量:2
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作者 华棣 《宇航学报》 EI CAS CSCD 北大核心 2010年第2期587-592,共6页
证明爱因斯坦立足于光速不变假设和长度收缩假设的洛伦茨变换未能正确地解释多普勒效应、红移和光行差现象;他也未能给出正确的动体的质能当量关系。作者立足于完全符合相对性原理的伽利略变换,成功地解决了上述问题。
关键词 爱因斯坦 洛伦茨变换 伽利略变换 相对性原理 光速不变 长度收缩 多普勒效应 红移 光行差 静体 动体 质能当量
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简化原理在Hilbert空间与可分Banach空间的一些应用 被引量:1
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作者 王志刚 《数学杂志》 CSCD 北大核心 2007年第3期312-316,共5页
本文研究了简化原理在Hilbert空间与可分Banach空间中的一些应用,利用简化原理和独立随机元收敛准则获得了中分Banach空间随机级数的收缩原理和B-值随机Dirichlet级数简单收敛横坐标及一般随机整函数的增长性和值分布,将许多以Rademache... 本文研究了简化原理在Hilbert空间与可分Banach空间中的一些应用,利用简化原理和独立随机元收敛准则获得了中分Banach空间随机级数的收缩原理和B-值随机Dirichlet级数简单收敛横坐标及一般随机整函数的增长性和值分布,将许多以Rademacher序列为系数的随机Tayor级数和随机Dirichlet级数的相关结果,推广到一般的具有独立对称分布系数的随机级数上去。 展开更多
关键词 简化原理 收缩原理 收敛横坐标 增长性 值分布
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APPROXIMATE INERTIAL MANIFOLDS TO THE NAVIER-STOKES EQUATIONS
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作者 王碧祥 《Annals of Differential Equations》 1994年第4期408-423,共16页
In this paper,we construct an infinite family of approximate inertial manifolds for the Navier-Stokes equations.These manifolds provide higher and higher order approximations to the attractor.Our manifolds are constru... In this paper,we construct an infinite family of approximate inertial manifolds for the Navier-Stokes equations.These manifolds provide higher and higher order approximations to the attractor.Our manifolds are constructed by contraction principle and therefore can be easily approximated by simple explicit functions in real computations. 展开更多
关键词 contraction principle attractor approximate inertial manifolds Navier-Stokes equations.
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Superimposing Scales and Doppler-Like Effect
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作者 Edward Szaraniec 《Journal of Modern Physics》 2019年第3期362-370,共9页
The observable universe together with the observer, both on sufficiently large scale, succeeds in their self-entaglement and paradoxical inconsistency. For consistency, the observable universe and the observer have to... The observable universe together with the observer, both on sufficiently large scale, succeeds in their self-entaglement and paradoxical inconsistency. For consistency, the observable universe and the observer have to be on different scale (size) provided, the cosmological principle is preserved as an approximation in a limit. The point is the univers’ principle itself. Our proposal for the disentaglement is superimposition out of complexity. The distance contraction, as observed in electrical soundings over horizontally stratified earth (static system), is identified as a counterpart of Doppler shift in dynamical systems. An alternative answer to the question about an effective cause of the Doppler shift sounds the heterogeneities under superimposing scales. The energy propagating in stratified universe exhibits a shift which could be attributed not only to the expansion but alternatively to fluctuations across different scales. When nothing is said or predetermined about kinematics of a system, both causes might share in the effect. It opens different static and kinematic possibilities, which challenge established theories of energy/information transmission and/or sounding at a distance as well as pertinent technology in prospect. 展开更多
关键词 Disentaglement Distance contraction DOPPLER EFFECT RAMA EFFECT SUPERIMPOSITION Univers’ principle
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Why Matter Occupies so Large a Volume?
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作者 E.B.Manoukian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期677-686,共10页
The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection wit... The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection with the Pauli exclusion principle, as more and more matter is put together, as well as of the contraction or shrinkage of "bosonic matter", upon collapse, for which the Panli exclusion is abolished. From the derived explicit bounds of integrals of powers of the particle number densities, explicit bounds on probabilities of the occurrences of the events just described are extracted. These probabilities lead one to infer the change of the "size" or extension of such matter, upon expansion or contraction, respectively, as their content is increased. 展开更多
关键词 expansion of matter and the Pauli exclusion principle contraction or shrinkage of "bosonic mat-ter" upon collapse
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引力场的时空特性研究
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作者 张宁 《邢台职业技术学院学报》 2007年第1期1-4,共4页
引力场是一种矢量场,广义相对论对引力问题的描述是非常有效的。分析了广义相对论中的等效原理和广义协变原理,讨论了爱因斯坦引力场方程,研究了相对性原理、引力场中的时间膨胀、长度收缩。
关键词 广义相对论 等效原理 引力场 时间膨胀 长度收缩
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On the existence and uniqueness of a nonlinear q-difference boundary value problem of fractional order
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作者 Zouaoui Bekri Vedat Suat Erturk Pushpendra Kumar 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2022年第1期265-284,共20页
In this research collection,we estimate the existence of the unique solution for the boundary value problem of nonlinear fractional q-difference equation having the given form c D^(ζ)_(q) v(t)−h(t,v(t))=0,0≤t≤1,α_... In this research collection,we estimate the existence of the unique solution for the boundary value problem of nonlinear fractional q-difference equation having the given form c D^(ζ)_(q) v(t)−h(t,v(t))=0,0≤t≤1,α_(1)v(0)+β_(1)D_(q)v(0)=v(η1),α_(2)v(1)−β_(2)D_(q)v(1)=v(η2),where 1<ζ≤2,(η1,η2)∈(0,1)^(2),α_(i),β_(i)∈R(i=1,2),h∈C([0,1]×R,R)and c Dζq represents the Caputo-type nonclassical q-derivative of orderζ.We use well-known principal of Banach contraction,and Leray–Schauder nonlinear alternative to vindicate the unique solution existence of the given problem.Regarding the applications,some examples are solved to justify our outcomes. 展开更多
关键词 Fractional q-derivative principle of Banach contraction Leary-Schauder non-linear alternative existence and uniqueness boundary value problem
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THE EXISTENCE AND UNIQUENESS OF SOLUTION FOR A CLASS OF STOCHASTIC FUNCTIONAL EQUAFIONS ON S.P.SPACE 被引量:10
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作者 刘坤会 秦明达 陆传赉 《Acta Mathematica Scientia》 SCIE CSCD 2001年第3期391-400,共10页
This paper is concerned with the existence and uniqueness of solution for a class of stochastic functional equation: X =φ(X), where φ: B → B and B is a Banach space consisted of all left-continuous, (■_t)-adapted ... This paper is concerned with the existence and uniqueness of solution for a class of stochastic functional equation: X =φ(X), where φ: B → B and B is a Banach space consisted of all left-continuous, (■_t)-adapted processes. Also, the main result is applied to some S.D.E (or S.I.E.). And the authors adopted some of the results in current research in the models of stochastic control recently. This paper proves the ekistence and uniquence and uniqueness of solution for stochastic functional equation. A series of corollaries are deduced from the special examples of the theorems in this paper. 展开更多
关键词 Stochastic functional equation stochastic differential (integral) equation principle of contraction mapping
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一类广义Sine-Gordon方程的概周期解 被引量:4
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作者 朴大雄 邱汶华 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期892-894,共3页
用最大值原理和Banach压缩映像原理研究一类广义Sine-Gordon方程的概周期解问题,证明概周期解的存在‖u‖L∞<π2中的唯一性。
关键词 广义Sine-Gordon方程 电报方程 概周期解 最大值原理 Banach压缩映像原理
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SIMPLE PROOF OF A LARGE DEVIATION RESULT
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作者 张志祥 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2001年第3期326-331,共6页
In this note we prove a large deviation result for a perturbed discontinuous inhomogeneous system which complements[1].
关键词 Large deviation principle stochastic differential equation contraction principle Donsker's invariance principle
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Convergence theorem of common fixed points for Lipschitzian pseudo-contraction semi-groups in Banach spaces
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第2期145-152,共8页
The purpose of this paper is to study the weak convergence problems of the implicity iteration process for Lipschitzian pseudocontractive semi-groups in the general Banach spaces. The results presented in this paper e... The purpose of this paper is to study the weak convergence problems of the implicity iteration process for Lipschitzian pseudocontractive semi-groups in the general Banach spaces. The results presented in this paper extend and improve the corresponding results of some people. 展开更多
关键词 Lipschitzian pseudo-contraction semi-group demi-closed principle common fixed point Opial condition strongly pseudo-contraction mapping implicit iteration process
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穿梭车用伸缩货叉的设计研究 被引量:3
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作者 姜延柏 尹世琛 +1 位作者 陈涤新 邹丽 《起重运输机械》 2020年第3期58-62,共5页
基于穿梭车的货到人拣选系统中,伸缩货叉是穿梭车上物料搬运的执行机构,它的合理设计是保证穿梭车轻巧、快速、精准的关键。文中进行伸缩货叉的研发设计,通过总体规划设计,确定伸缩货叉的性能参数;通过分析常用结构形式的弊端,合理设计... 基于穿梭车的货到人拣选系统中,伸缩货叉是穿梭车上物料搬运的执行机构,它的合理设计是保证穿梭车轻巧、快速、精准的关键。文中进行伸缩货叉的研发设计,通过总体规划设计,确定伸缩货叉的性能参数;通过分析常用结构形式的弊端,合理设计伸缩货叉各部件结构,使伸缩货叉具有较大行程、足够强度的同时,结构先进合理,简单紧凑,外形尺寸小,方便选材,成本低,传动平稳,定位精确,易于操作,更加具有市场竞争力。 展开更多
关键词 穿梭车 伸缩货叉 组成结构 伸缩原理 总体规划 部件设计
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一类广义非线性变分不等式解的存在性及迭代算法 被引量:3
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作者 高海燕 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2013年第1期136-139,共4页
解决一类新的广义非线性变分不等式解问题,定义了强单调映射和Lipschitz连续性的概念,利用辅助原理和压缩映射原理,研究了包含强制连续双线性型a(u,v)和非线性型b(u,v)的变分不等式解的存在性,同时构造了一种新的迭代算法,证明了迭代算... 解决一类新的广义非线性变分不等式解问题,定义了强单调映射和Lipschitz连续性的概念,利用辅助原理和压缩映射原理,研究了包含强制连续双线性型a(u,v)和非线性型b(u,v)的变分不等式解的存在性,同时构造了一种新的迭代算法,证明了迭代算法的收敛性.文中的结果推广和改进了文献中的相应结论. 展开更多
关键词 广义非线性变分不等式 辅助原理技术 压缩映射 不动点 强单调 LIPSCHITZ连续 迭代算法 收敛性
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一般类型随机Volterra积分方程解的存在唯一性 被引量:2
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作者 郭英 李文学 王克 《黑龙江大学自然科学学报》 CAS 北大核心 2009年第2期201-205,210,共6页
用随机Volterra方程刻画的数学模型,常见于许多经济、生态和化学等问题中,具有广泛的实际应用前景。给出随机Volterra方程解的定义及解的存在唯一性定理,应用压缩映像原理证明了一般类型随机Volterra方程的特殊形式的方程解的存在唯一性... 用随机Volterra方程刻画的数学模型,常见于许多经济、生态和化学等问题中,具有广泛的实际应用前景。给出随机Volterra方程解的定义及解的存在唯一性定理,应用压缩映像原理证明了一般类型随机Volterra方程的特殊形式的方程解的存在唯一性,随后给出并证明了一般类型随机Volterra方程的解的存在唯一性。 展开更多
关键词 随机Volterra积分方程 存在唯一性 压缩映像原理
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