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Strong invariance principle for a counterbalanced random walk
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作者 TAN Hui-qun HU Zhi-shui DONG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期370-380,共11页
We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 wit... We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n). 展开更多
关键词 random walk MARTINGALE invariance principle
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A Supplement to the Invariance Principle of the Speed of Light and the Quantum Theory
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作者 Yuanjie Li Wenchuan Jia Jiale Wang 《Journal of Modern Physics》 2015年第2期126-130,共5页
Richard Feynman once said, “I think it is safe to say that no one understands Quantum Mechanics”. The well-known article on the Einstein-Podolsky-Rosen (EPR) paradox brought forth further doubts on the interpretatio... Richard Feynman once said, “I think it is safe to say that no one understands Quantum Mechanics”. The well-known article on the Einstein-Podolsky-Rosen (EPR) paradox brought forth further doubts on the interpretation of quantum theory. Einstein’s doubt on quantum theory is a doubleedged sword: experimental verification of quantum theory would contradict the hypothesis that speed of light is finite. It has been almost a century since the creation of quantum theory and special relativity, and the relevant doubts brought forward remain unresolved. We posit that the existence of discontinuity points and quantum wormholes would imply superluminal phenomenon or infinite speed of light, which provides for an important supplement to the invariance principle of the speed of light and superluminal phenomena. This can potentially resolve the inconsistency between special relativity and quantum theory. 展开更多
关键词 invariANCE principle of the Speed of Light SUPERLUMINAL Phenomena Uncertainty principle QUANTUM NONLOCALITY QUANTUM WORMHOLES
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Should the Galilean Invariance be Kept as a Guiding Principle for Selecting the Interaction Potentials?
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作者 Zong, Hongshi Wang, Fan 《Chinese journal of nuclear physics》 EI 1997年第1期31-34,共4页
Galilean invariance is a nonrelativistic principle,which should not be kept as a guid-ing principle in discriminating the interaction potential terms derived from field theory.
关键词 Calilean invariANCE Interaction POTENTIALS GUIDING principle
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Controlling Chaos in Neuron Based on Lasalle Invariance Principle
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作者 韦笃取 覃英华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期459-462,共4页
A new control law is proposed to asymptotically stabilize the chaotic neuron system based on LaSalleinvariant principle.The control technique does not require analytical knowledge of the system dynamics and operateswi... A new control law is proposed to asymptotically stabilize the chaotic neuron system based on LaSalleinvariant principle.The control technique does not require analytical knowledge of the system dynamics and operateswithout an explicit knowledge of the desired steady-state position.The well-known modified Hodgkin-Huxley (MHH)and Hindmarsh-Rose (HR) model neurons are taken as examples to verify the implementation of our method.Simulationresults show the proposed control law is effective.The outcome of this study is significant since it is helpful to understandthe learning process of a human brain towards the information processing,memory and abnormal discharge of the brainneurons. 展开更多
关键词 神经元 不变性原理 混沌控制 拉萨 系统动力学分析 人类大脑 神经系统 控制技术
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An Invariance Principle for ρ^--Mixing Random Sequences
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作者 LIU Xiao-ping YAN Han WU Qun-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期470-474,共5页
在这份报纸,我们建立一个不变性原则为 -- 在某时刻 condition.The 结果下面混合随机的 se quences 改进并且延长吴(2003 ) 的相关结果。
关键词 -- 混合随机的顺序 不变性原则 时刻状况
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Conserved quantities and adiabatic invariants of fractional Birkhoffian system of Herglotz type 被引量:2
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作者 丁娟娟 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期303-311,共9页
In order to further study the dynamical behavior of nonconservative systems,we study the conserved quantities and the adiabatic invariants of fractional Brikhoffian systems with four kinds of different fractional deri... In order to further study the dynamical behavior of nonconservative systems,we study the conserved quantities and the adiabatic invariants of fractional Brikhoffian systems with four kinds of different fractional derivatives based on Herglotz differential variational principle.Firstly,the conserved quantities of Herglotz type for the fractional Brikhoffian systems based on Riemann-Liouville derivatives and their existence conditions are established by using the fractional Pfaff-Birkhoff-d Alembert principle of Herglotz type.Secondly,the effects of small perturbations on fractional Birkhoffian systems are studied,the conditions for the existence of adiabatic invariants for the Birkhoffian systems of Herglotz type based on Riemann-Liouville derivatives are established,and the adiabatic invariants of Herglotz type are obtained.Thirdly,the conserved quantities and adiabatic invariants for the fractional Birkhoffian systems of Herglotz type under other three kinds of fractional derivatives are established,namely Caputo derivative,Riesz-Riemann-Liouville derivative and Riesz-Caputo derivative.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 FRACTIONAL BIRKHOFFIAN system Pfaff-Birkhoff-d’Alembert principle ADIABATIC invariant Herglotz generalized VARIATIONAL principle
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STRONG COMPARISON PRINCIPLES FOR SOME NONLINEAR DEGENERATE ELLIPTIC EQUATIONS 被引量:1
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作者 李岩岩 王博 《Acta Mathematica Scientia》 SCIE CSCD 2018年第5期1583-1590,共8页
In this paper, we obtain the strong comparison principle and Hopf Lemma for locally Lipschitz viscosity solutions to a class of nonlinear degenerate elliptic operators of the form △2ψ + L(x,△ ψ), including the ... In this paper, we obtain the strong comparison principle and Hopf Lemma for locally Lipschitz viscosity solutions to a class of nonlinear degenerate elliptic operators of the form △2ψ + L(x,△ ψ), including the conformal hessian operator. 展开更多
关键词 Hopf lemma strong comparison principle degenerate ellipticity conformal invariance
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STUDY OF THE EQUIVALENT THEOREM OF GENERALIZED VARIATIONAL PRINCIPLES IN ELASTICITY
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作者 张国清 余建星 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期347-357,共11页
The relations of all generalized variational principles in elasticity are studied by employing the invariance theorem of field theory. The infinitesimal scale transformation in field theory was employed to investigate... The relations of all generalized variational principles in elasticity are studied by employing the invariance theorem of field theory. The infinitesimal scale transformation in field theory was employed to investigate the equivalent theorem. Among the results found particularly interesting are those related to that all generalized variational principles in elasticity are equal to each other. Also studied result is that only two variables are independent in the functional and the stress-strain relation is the variational constraint condition for all generalized variational principles in elasticity. This work has proven again the conclusion of Prof. Chien Wei-zang. 展开更多
关键词 ELASTICITY generalized variational principle equivalent theorem scale transformation invariANCE
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A new type of adiabatic invariants for disturbed non-conservative nonholonomic system
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作者 徐鑫鑫 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期118-122,共5页
According to the Herglotz variational principle and differential variational principle of Herglotz type, we study the adiabatic invariants for a non-conservative nonholonomic system. Firstly, the differential equation... According to the Herglotz variational principle and differential variational principle of Herglotz type, we study the adiabatic invariants for a non-conservative nonholonomic system. Firstly, the differential equations of motion of the non-conservative nonholonomic system based upon the generalized variational principle of Herglotz type are given, and the exact invariant for the non-conservative nonholonomic system is introduced. Secondly, a new type of adiabatic invariant for the system under the action of a small perturbation is obtained. Thirdly, the inverse theorem of the adiabatic invariant is given. Finally, an example is given. 展开更多
关键词 non-conservative nonholonomic mechanics adiabatic invariants differential variational principle of Herglotz type
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Maximum Principles for Normal Matrices
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作者 Achiya Dax 《Advances in Linear Algebra & Matrix Theory》 2019年第3期73-81,共9页
Ky Fan maximum principle is a well-known observation about traces of certain hermitian matrices. In this note, we derive a powerful extension of this claim. The extension is achieved in three ways. First, traces are r... Ky Fan maximum principle is a well-known observation about traces of certain hermitian matrices. In this note, we derive a powerful extension of this claim. The extension is achieved in three ways. First, traces are replaced with norms of diagonal matrices, and any unitarily invariant norm can be used. Second, hermitian matrices are replaced by normal matrices, so the rule applies to a larger class of matrices. Third, diagonal entries can be replaced with eigenvalues and singular values. It is shown that the new maximum principle is closely related to the problem of approximating one matrix by another matrix of a lower rank. 展开更多
关键词 KY FAN MAXIMUM principle Normal MATRICES Extended MAXIMUM principle Unitarily invariant Norms
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A Formulation of Quantum Theory Based on Two Physical Principles
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作者 R. T. Deck 《Journal of Modern Physics》 2015年第4期434-447,共14页
We demonstrate two points: 1) the formalism of quantum mechanics can be understood simply as a structure for the expression of the physical notion that not all observables can have values simultaneously;2) the specifi... We demonstrate two points: 1) the formalism of quantum mechanics can be understood simply as a structure for the expression of the physical notion that not all observables can have values simultaneously;2) the specific uncertainty relations can be derived (rigorously) by combination of the invariance principle with a general uncertainty relation based only on the existence of unspecified pairs of conjugate observables. For this purpose, we present a formulation of quantum mechanics based strictly on the invariance principle and a “weak” statement of the uncertainty principle that asserts only the existence of incompatible (conjugate) observables without specifying which observables are incompatible. We go on to show that the invariance principle can be used to develop the equations of motion of the theory, including the Klein-Gordon and Schrodinger equations. 展开更多
关键词 Uncertainty principle invariANCE principle KLEIN-GORDON EQUATION SCHRODINGER EQUATION
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Bound States of a System of Two Fermions on Invariant Subspace
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作者 J. I. Abdullaev A. M. Toshturdiev 《Journal of Modern Physics》 2021年第1期35-49,共15页
We consider a Hamiltonian of a system of two fermions on a three-dimensional lattice Z<sup>3</sup> with special potential <img alt="" src="Edit_56564354-6d65-4104-9126-d4657fa750af.png&qu... We consider a Hamiltonian of a system of two fermions on a three-dimensional lattice Z<sup>3</sup> with special potential <img alt="" src="Edit_56564354-6d65-4104-9126-d4657fa750af.png" />. The corresponding Shr&ouml;dinger operator <em>H</em>(<strong>k</strong>) of the system has an invariant subspac <span style="white-space:nowrap;"><span><em>L</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(T<sup>3</sup>)</span> , where we study the eigenvalues and eigenfunctions of its restriction <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub></span><span style="white-space:nowrap;">(<strong>k</strong>)</span>. Moreover, there are shown that <span style="white-space:nowrap;"><span><em>H</em></span><sup>-</sup><sub style="margin-left:-10px;">123</sub>(<em>k</em><sub>1</sub>, <em>k</em><sub>2</sub>, π)</span> has also infinitely many invariant subspaces <img alt="" src="Edit_4955ffad-4b18-434a-8c99-ff14779f2812.bmp" />, where the eigenvalues and eigenfunctions of eigenvalue problem <img alt="" src="Edit_01b218d2-fa3e-4f39-bc2d-ce736205db93.bmp" />are explicitly found. 展开更多
关键词 Hamiltonian FERMION Bound State Shrödinger Operator invariant Subspace Total Quasi-Momentum EIGENVALUE Birman-Schwinger principle
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A New Version of Special Relativity Absorbed the Uncertainty Principle: Its Content as Well as Application and Experimental Test
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作者 Dapeng Qian 《Journal of Modern Physics》 2014年第12期1146-1166,共21页
Based on the space spherical symmetry of 3-dimensional and the translational symmetry of time and the uncertainty principle, a 4-dimensional space-time cylinder model of quarks and leptons is established. With this mo... Based on the space spherical symmetry of 3-dimensional and the translational symmetry of time and the uncertainty principle, a 4-dimensional space-time cylinder model of quarks and leptons is established. With this model, equations of the special relativity can be extended more perfectly, thereby achieving a unity of the special relativity and quantum mechanics in deeper level. New equations can not only interpret issues explained by old equations but also solve several important pending problems. For example, a formula to strictly calculate the coefficient ξ of Lorentz invariance violation (LIV) is derived, to above 4 × 1019 eV UHECR protons the calculated |ξ| -30, although there is the LIV effect it is too weak to change the GZK cutoff, which is consistent with observations of HiRes and Auger;Also, a relation formula between the Hubble constant and several basic constants is derived, thus theoretically calculated H0 = 70.937 km·s-1·Mpc-1, which is well consistent with the final observation result of HST Key Project. In addition, an unusual effect predicted by new equations can be experimentally tested in the electron storage ring;a preliminary experiment result has hinted its signs of existence. 展开更多
关键词 Special Relativity Uncertainty principle Cylinder Model with Intrinsic 4-Dimensional Space-Time of Quarks/Leptons Lorentz invariance Violation GZK Cutoff of UHECR Planck ENERGY HUBBLE Constant Super-High ENERGY ELECTRON ELECTRON Storage Ring
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The Proof That There Are No Invariabilities of Lorentz Transformations in the Interaction Theories of Micro-Particle Physics 被引量:1
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作者 Xiaochun Mei 《Journal of Modern Physics》 2014年第8期599-616,共18页
It is proved in this paper that there are at least five situations in the interaction theories of microparticle physics that the Lorentz transformations have no invariabilities. 1) In the formula to calculate transiti... It is proved in this paper that there are at least five situations in the interaction theories of microparticle physics that the Lorentz transformations have no invariabilities. 1) In the formula to calculate transition probabilities in particle physics, the so-called invariability factor of phase space d3p/E is not invariable actually under the Lorentz transformations. Only in one-dimensional motion with uy = uz = 0, it is invariable. 2) The propagation function of spinor field in quantum theory of field has no invariability of Lorentz Transformation actually. What appears in the transformation is the sum of Lorentz factors aμνaλμ ≠ δνλ when ν, λ = 1, 4, rather than aμνaλμ = δνλ. But in the current calculation, we take aμνaλμ = δνλ. The confusion of subscript’s position leads to wrong result. 3) Though the motion equations of quantum fields and the interaction Hamiltonian are unchanged under the Lorentz transformation, the motion equation of perturbation which is used to calculate the transition probability in the interaction representation has no invariability. 4) The interactions between bound state’s particles have no Lorentz invariability. In fact, the principle of relativity has no approximation if it holds. 5) The calculation methods of high order perturbations normalization processes in quantum theory of fields violate the invariability of Lorentz transformation. The conclusions above are effective for strong, weak and electromagnetic interactions and so on. Therefore, the principle of relativity does not hold in the micro-particle’s interactions. On the other hand, the invariability principle of light’s speed is still effective. So the formulas of special relativity still hold, but we should consider them with absolute significances. 展开更多
关键词 principle of RELATIVITY LORENTZ invariability VIOLATION QUANTUM Theory of Filed QUANTUM Mechanics Phase Space Factor Propagation Function Normalization CMBR Cosmology
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FORM INVARIANCE AND NOETHER SYMMETRICAL CONSERVED QUANTITY OF RELATIVISTIC BIRKHOFFIAN SYSTEMS
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作者 罗绍凯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第4期468-478,共11页
A form invariance of the relativistic Birkhoffian system is studied, and the conserved quantities of the system are obtained. Under the infinitesimal transformation of groups, the definition and criteria of the form i... A form invariance of the relativistic Birkhoffian system is studied, and the conserved quantities of the system are obtained. Under the infinitesimal transformation of groups, the definition and criteria of the form invariance of the system were given. In view of the invariance of relativistic Pfaff_Birkhoff_ D'Alembert principle under the infinitesimal transformation of groups, the theory of Noether symmetries of the relativistic Birkhoffian system were constructed. The relation between the form invariance and the Noether symmetry is studied, and the results show that the form invariance can also lead to the Noether symmetrical conserved quantity of the relativistic Birkhoffian system under certain conditions. 展开更多
关键词 RELATIVITY Birkhoffian system Pfaff_Birkhoff_ D'Alembert principle form invariance Noether symmetry conserved quantity
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一类具有时滞的COVID-19动力学模型及传播预测
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作者 董庆来 周楚钰 刘聘 《甘肃科学学报》 2023年第4期1-8,共8页
建立可用于COVID-19疫情评估的一类具有时滞的新冠肺炎传播动力学模型(SI 2R模型)。研究利用时滞描述感染者在核酸检测阳性前的潜伏期,考虑防控隔离和医学追踪隔离等隔离措施的效果,将感染者分为两类:一类感染者具有传染能力,另一类感... 建立可用于COVID-19疫情评估的一类具有时滞的新冠肺炎传播动力学模型(SI 2R模型)。研究利用时滞描述感染者在核酸检测阳性前的潜伏期,考虑防控隔离和医学追踪隔离等隔离措施的效果,将感染者分为两类:一类感染者具有传染能力,另一类感染者由于被隔离其感染能力可忽略不计,构建了SI 2R模型,并详细讨论系统解的存在性、有界性和平衡点的分类,再利用Lyapunov-LaSalle不变性原理证明了平衡点的全局稳定性。以2021年12月15日—2022年1月13日的西安市疫情数据为依据,拟合得到SI^(2)R模型的动力学参数,对西安市COVID-19疫情进行了预测和评估。结果表明,具有时滞的SI 2R传染病动力学模型对疫情的理论估计与西安市疫情的实际情况较为符合,可用于COVID-19传播行为分析,为疫情防控策略的制定提供了理论支持。 展开更多
关键词 应用数学 COVID-19 时滞动力学模型 稳定性 Lyapunov-LaSalle不变性原理
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一类由α-稳定过程驱动的随机时滞微分方程的LaSalle不变原理
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作者 张振中 陈旭 童金英 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第4期11-23,共13页
LaSalle不变原理是研究随机系统稳定性的重要工具.考虑到时滞与样本轨道跳跃对系统稳定性的影响,本文通过特殊半鞅的收敛性,建立了一类由α-稳定过程驱动的随机时滞微分方程的LaSalle不变原理.利用LaSalle不变原理给出了一类延迟方程解... LaSalle不变原理是研究随机系统稳定性的重要工具.考虑到时滞与样本轨道跳跃对系统稳定性的影响,本文通过特殊半鞅的收敛性,建立了一类由α-稳定过程驱动的随机时滞微分方程的LaSalle不变原理.利用LaSalle不变原理给出了一类延迟方程解渐进稳定的充分条件. 展开更多
关键词 LaSalle不变原理 特殊半鞅 依概率渐近稳定性 依概率稳定性
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An invariance principle for negatively associated random variables 被引量:4
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作者 LIN ZhengyanDepartment of Mathematics and Information Science, Hangzhou University, Hangzhou 310028, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第5期359-364,共6页
A finite collection of random variables, X<sub>1</sub>,…, X<sub>n</sub> (n≥2), is said to be negatively associated (NA) if any two coordinatewise nondecreasing (or nonincreasing) functi... A finite collection of random variables, X<sub>1</sub>,…, X<sub>n</sub> (n≥2), is said to be negatively associated (NA) if any two coordinatewise nondecreasing (or nonincreasing) functions f<sub>1</sub> and f<sub>2</sub> on R<sup>n</sup>, such that (?)<sub>j</sub>=f<sub>j</sub>(X<sub>1</sub>,…,X<sub>n</sub>) have a finite variance for j=1, 2 and Cov((?)<sub>1</sub>,(?)<sub>2</sub>)≤0; an infinite collection is said to be NA if every finite subcollection is NA. It is relative to a lot of practical problems, such as reliability theory, percolation models and multivariate statistical analysis. Matula (1992) studied the strong laws of large numbers for an NA sequence. Recent- 展开更多
关键词 negatively ASSOCIATED RANDOM VARIABLES WEAK invariANCE principle.
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具有恐惧效应的时滞捕食者-食饵模型 被引量:1
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作者 王灵芝 《吉林大学学报(理学版)》 CAS 北大核心 2023年第3期449-458,共10页
考虑一类具有恐惧效应的时滞捕食者-食饵模型.先利用特征方程和Lyapunov-LaSalle不变性原理,证明当R(τ)≤1时边界平衡点的全局渐近稳定性;再利用时滞微分方程Hopf分支理论,讨论当R(τ)>1时共存平衡点的稳定性和全局Hopf分支的存在性... 考虑一类具有恐惧效应的时滞捕食者-食饵模型.先利用特征方程和Lyapunov-LaSalle不变性原理,证明当R(τ)≤1时边界平衡点的全局渐近稳定性;再利用时滞微分方程Hopf分支理论,讨论当R(τ)>1时共存平衡点的稳定性和全局Hopf分支的存在性,得到了恐惧效应与时滞会影响系统稳定性的结果;最后通过数值模拟验证理论结果的正确性. 展开更多
关键词 恐惧效应 时滞 Lyapunov-LaSalle不变性原理 HOPF分支
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Donsker’s Invariance Principle Under the Sub-linear Expectation with an Application to Chung’s Law of the Iterated Logarithm 被引量:18
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作者 Li-Xin Zhang 《Communications in Mathematics and Statistics》 SCIE 2015年第2期187-214,共28页
We prove a new Donsker’s invariance principle for independent and identically distributed random variables under the sub-linear expectation.As applications,the small deviations and Chung’s law of the iterated logari... We prove a new Donsker’s invariance principle for independent and identically distributed random variables under the sub-linear expectation.As applications,the small deviations and Chung’s law of the iterated logarithm are obtained. 展开更多
关键词 Sub-linear expectation Capacity Central limit theorem invariance principle Chung’s law of the iterated logarithm Small deviation
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