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THE CONSTRUCTION OF DENUMERABLE q-PROCESSES IN RANDOM ENVIRONMENTS-THE EXISTENCE AND UNIQUENESS 被引量:3
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作者 胡迪鹤 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期225-235,共11页
The concepts of Markov process in random environment, q-matrix in random environment, and q-process in random environment are introduced. The minimal q-process in random environment is constructed and the necessary an... The concepts of Markov process in random environment, q-matrix in random environment, and q-process in random environment are introduced. The minimal q-process in random environment is constructed and the necessary and sufficient conditions for the uniqueness of q-process in random environment are given. 展开更多
关键词 Markov process in random environment q-matrix in random environment q-process in random environment
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THE CONSTRUCTION OF DENUMERABLE q-PROCESSES IN RANDOM ENVIRONMENTS SATISFYING (F) OR (B) 被引量:2
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作者 胡迪鹤 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期975-988,共14页
This article is a continuation of[9].Based on the discussion of random Kolmogorov forward(backward)equations,for any given q-matrix in random environment, Q(θ)=(q(θ;x,y),x,y∈X),an infinite class of q-proces... This article is a continuation of[9].Based on the discussion of random Kolmogorov forward(backward)equations,for any given q-matrix in random environment, Q(θ)=(q(θ;x,y),x,y∈X),an infinite class of q-processes in random environments satisfying the random Kolmogorov forward(backward)equation is constructed.Moreover, under some conditions,all the q-processes in random environments satisfying the random Kolmogorov forward(backward)equation are constructed. 展开更多
关键词 Markov process in random environment q-matrix in random environment q-process in random environment
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THE EXISTENCE AND MOMENTS OF CANONICAL BRANCHING CHAIN IN RANDOM ENVIRONMENT 被引量:19
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作者 HuDihe 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期499-506,共8页
The concepts of branching chain in random environmnet and canonical branching chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical ex... The concepts of branching chain in random environmnet and canonical branching chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment are also given. 展开更多
关键词 random transition matrix branching chain in random environment canonical branching chains in random environments generator random varialble
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Research on color image matching method based on feature point compensation in dark light environment 被引量:1
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作者 唐华鹏 QIN Danyang +2 位作者 YAN Mengying YANG Jiaqiang ZHANG Gengxin 《High Technology Letters》 EI CAS 2023年第1期78-86,共9页
Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching ... Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching is widely used in target recognition and tracking,indoor positioning and navigation.Local features missing,however,often occurs in color images taken in dark light,making the extracted feature points greatly reduced in number,so as to affect image matching and even fail the target recognition.An unsharp masking(USM)based denoising model is established and a local adaptive enhancement algorithm is proposed to achieve feature point compensation by strengthening local features of the dark image in order to increase amount of image information effectively.Fast library for approximate nearest neighbors(FLANN)and random sample consensus(RANSAC)are image matching algorithms.Experimental results show that the number of effective feature points obtained by the proposed algorithm from images in dark light environment is increased,and the accuracy of image matching can be improved obviously. 展开更多
关键词 dark light environment unsharp masking(USM) denoising model feature point compensation fast library for approximate nearest neighbor(FLANN) random sample consensus(RANSAC)
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THE CLASSIFICATION AND PERIOD OF STATES FOR MARKOV CHAIN IN RANDOM ENVIRONMENT 被引量:11
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期23-29,共7页
This paper is a continuation of [8]. In Section 1, three kinds of communication are introdnced for two states and the relations among them are investigated. In Section 2, two kinds of period of a state are introdnced ... This paper is a continuation of [8]. In Section 1, three kinds of communication are introdnced for two states and the relations among them are investigated. In Section 2, two kinds of period of a state are introdnced and it is obtained that the period is a 'class property',i.e. two states x and y belong to same class implies the period of x is equal to the period of y. 展开更多
关键词 Markov chain in random environment recurrent state transient state PERIOD
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ON MARKOV CHAINS IN SPACE-TIME RANDOM ENVIRONMENTS 被引量:7
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作者 胡迪鹤 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期1-10,共10页
In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTR... In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTRE(+) by an initial distribution Φ and a random Markov kernel (RMK) p(γ). In Section 3, the authors es-tablish several equivalence theorems on MCSTRE and MCSTRE(+). Finally, the authors give two very important examples of MCMSTRE, the random walk in spce-time random environment and the Markov br... 展开更多
关键词 random Markov kernel Markov chain in space-time random environemnt random walk in space-time random environment Markov branching chain in space-time random environment
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ASYMPTOTIC PROPERTIES OF A BRANCHING RANDOM WALK WITH A RANDOM ENVIRONMENT IN TIME 被引量:4
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作者 Yuejiao WANG Zaiming LIU +1 位作者 Quansheng LIU Yingqiu LI 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1345-1362,共18页
We consider a branching random walk in an independent and identically distributed random environment ξ=(ξn) indexed by the time. Let W be the limit of the martingale Wn=∫e^-txZn(dx)/Eξ∫e^-txZn(dx), with Zn denoti... We consider a branching random walk in an independent and identically distributed random environment ξ=(ξn) indexed by the time. Let W be the limit of the martingale Wn=∫e^-txZn(dx)/Eξ∫e^-txZn(dx), with Zn denoting the counting measure of particles of generation n, and Eξ the conditional expectation given the environment ξ. We find necessary and sufficient conditions for the existence of quenched moments and weighted moments of W, when W is non-degenerate. 展开更多
关键词 branching random WALK random environment quenched MOMENTS WEIGHTED MOMENTS
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CENTRAL LIMIT THEOREMS FOR A BRANCHING RANDOM WALK WITH A RANDOM ENVIRONMENT IN TIME 被引量:6
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作者 高志强 刘全升 汪和松 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期501-512,共12页
We consider a branching random walk with a random environment m time, in which the offspring distribution of a particle of generation n and the distribution of the displacements of its children depend on an environmen... We consider a branching random walk with a random environment m time, in which the offspring distribution of a particle of generation n and the distribution of the displacements of its children depend on an environment indexed by the time n. The envi- ronment is supposed to be independent and identically distributed. For A C R, let Zn(A) be the number of particles of generation n located in A. We show central limit theorems for the counting measure Zn (-) with appropriate normalization. 展开更多
关键词 Branching random walk random environment in time central limit theorems
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THE DECOMPOSITION OF STATE SPACE FOR MARKOV CHAIN IN RANDOM ENVIRONMENT 被引量:6
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期555-568,共14页
This paper is a continuation of [8] and [9]. The author obtains the decomposition of state space X of an Markov chain in random environment by making use of the results in [8] and [9], gives three examples, random wal... This paper is a continuation of [8] and [9]. The author obtains the decomposition of state space X of an Markov chain in random environment by making use of the results in [8] and [9], gives three examples, random walk in random environment, renewal process in random environment and queue process in random environment, and obtains the decompositions of the state spaces of these three special examples. 展开更多
关键词 Markov chain in random environment recurrent state transient state DECOMPOSITION
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THE CONSTRUCTION OF MULTITYPE CANONICAL MARKOV BRANCHING CHAINS IN RANDOM ENVIRONMENTS 被引量:2
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期431-442,共12页
The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introd... The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introduces the concepts of the multitype canonical Markov branching chain in random environment (CMBCRE) and multitype Markov branching chain in random environment (MBCRE) and proved that CMBCRE must be MBCRE, and any MBCRE must be equivalent to another CMBCRE in distribution. The main results of this article are the construction of CMBCRE and some of its probability properties. 展开更多
关键词 random Markov matrix Markov chain in random environment Markov branching chain in random environment canonical Markov branching chain in random environment generator random variables
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Some Probability Properties of Random Walk in Time-Random Environment 被引量:3
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作者 ZhangXiao-min LiBo 《Wuhan University Journal of Natural Sciences》 CAS 2004年第2期139-143,共5页
A general formulation of the stochastic model for random walk in time-random environment and an equivalent definition is established in this paper. Moreover, some basic probability relations similar to the classical c... A general formulation of the stochastic model for random walk in time-random environment and an equivalent definition is established in this paper. Moreover, some basic probability relations similar to the classical case which are very useful in the corresponding research of fractal properties are given. At the end, a typical example is provided to show the recurrence and transience. Key words random environment - random walk in timerandom environment - skew product Markov chain CLC number O 211.6 Foudation item: Supported by the National Natural Science Foundation of China (10371092) and Foundation of Wuhan University.Biography: Zhang Xiao-min (1977-), male, Ph. D candidate, research direction: stochastic processes and random fractal. 展开更多
关键词 random environment random walk in timerandom environment skew product Markov chain
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RENEWAL THEOREM FOR(L,1)-RANDOM WALK IN RANDOM ENVIRONMENT 被引量:2
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作者 洪文明 孙鸿雁 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1736-1748,共13页
We consider a random walk on Z in random environment with possible jumps {-L,…, -1, 1}, in the case that the environment {ωi : i ∈ Z} are i.i.d.. We establish the renewal theorem for the Markov chain of "the envi... We consider a random walk on Z in random environment with possible jumps {-L,…, -1, 1}, in the case that the environment {ωi : i ∈ Z} are i.i.d.. We establish the renewal theorem for the Markov chain of "the environment viewed from the particle" in both annealed probability and quenched probability, which generalize partially the results of Kesten (1977) and Lalley (1986) for the nearest random walk in random environment on Z, respectively. Our method is based on (L, 1)-RWRE formulated in Hong and Wang the intrinsic branching structure within the (2013). 展开更多
关键词 random walk in random environment renewal theorem multitype branchingprocess in random environment COUPLING
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Laplace Transformation and Ergodic Potential Kernel for q-Process in Random Environment 被引量:2
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作者 LU Ping HU Dihe 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期218-224,共7页
This paper introduces some concepts such as q- process in random environment, Laplace transformation, ergodic potential kernel, error function and some basic lemmas.We study the continuity and Laplace transformation o... This paper introduces some concepts such as q- process in random environment, Laplace transformation, ergodic potential kernel, error function and some basic lemmas.We study the continuity and Laplace transformation of random transition function. Finally, we give the sufficient condition for the existence of ergodic potential kernel for homogeneous q- processes in random environments. 展开更多
关键词 random transition function transition density func-tion in random environment q-process in random environment Laplace transformation ergodic potential kernel
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Model of Markov Chains in Space-Time Random Environments 被引量:2
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作者 YANG Guangyu HU Dihe 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期225-229,共5页
A general framework of stochastic model for a Markov chain in a space-time random environment is introduced, here the environment ξ^*:={ξ1,x∈N,x∈ X}is a random field. We study the dependence relations between th... A general framework of stochastic model for a Markov chain in a space-time random environment is introduced, here the environment ξ^*:={ξ1,x∈N,x∈ X}is a random field. We study the dependence relations between the environment and the original chain, especially the "feedback". Some equivalence theorems and law of large numbers are obtained. 展开更多
关键词 Markov chains in space-time random environments FEEDBACK Markovian environments
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RECURRENCE FOR THE GENERALIZED BIRTH-DEATH CHAINS IN A RANDOM ENVIRONMENT 被引量:5
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作者 丁万鼎 《Acta Mathematica Scientia》 SCIE CSCD 1990年第1期111-120,共10页
This is a study of one dimensional generalized birth-death chains in a random environment (GBDIRE). We give two sufficient conditions of recurrence for GBDIRE.
关键词 TH RECURRENCE FOR THE GENERALIZED BIRTH-DEATH CHAINS IN A random environment RTH exp
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THE ERGODICITY FOR BI-IMMIGRATION BIRTH AND DEATH PROCESSES IN RANDOM ENVIRONMENT 被引量:1
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作者 胡迪鹤 张书林 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期43-53,共11页
The concepts of bi-immigration birth and death density matrix in random environment and bi-immigration birth and death process in random environment are introduced. For any bi-immigration birth and death matrix in ran... The concepts of bi-immigration birth and death density matrix in random environment and bi-immigration birth and death process in random environment are introduced. For any bi-immigration birth and death matrix in random environment Q(θ) with birth rate λ 〈 death rate μ, the following results are proved, (1) there is an unique q-process in random environment, P^-(θ*(0);t) = (p^-(θ^*(0);t,i,j),i,j ≥ 0), which is ergodic, that is, lim t→∞(θ^*(0);t,i,j) = π^-(θ^*(0);j) ≥0 does not depend on i ≥ 0 and ∑j≥0π (θ*(0);j) = 1, (2) there is a bi-immigration birth and death process in random enjvironment (X^* = {X^*,t ≥ 0},ε^* = {εt,t ∈ (-∞, ∞)}) with random transition matrix P^-(θ^* (0);t) such that X^* is a strictly stationary process. 展开更多
关键词 Density matrix in random environment random transition matrix Markov process in random environment bi-immigration birth and death density matrix in random environment bi-immigration birth and death process in random environment
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LIMIT THEOREMS FOR A GALTON-WATSON PROCESS IN THE I.I.D. RANDOM ENVIRONMENT 被引量:2
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作者 高振龙 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1193-1205,共13页
In this article, we obtain the central limit theorem and the law of the iterated logarithm for Galton-Watson processes in i.i.d, random environments.
关键词 Galton-Watson process in random environment central limit theorem law of the iterated logarithm
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MOMENTS OF CONTINUOUS-STATE BRANCHING PROCESSES IN LéVY RANDOM ENVIRONMENTS 被引量:1
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作者 Lina JI Xiangqi ZHENG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期781-796,共16页
For continuous-state branching processes in Lévy random environments, the recursion of n-moments and the equivalent condition for the existence of general f-moments are established, where f is a positive continuo... For continuous-state branching processes in Lévy random environments, the recursion of n-moments and the equivalent condition for the existence of general f-moments are established, where f is a positive continuous function satisfying some standard conditions. 展开更多
关键词 Branching processes continuous-state MOMENTS random environment stochastic EQUATIONS
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MOMENTS AND LARGE DEVIATIONS FOR SUPERCRITICAL BRANCHING PROCESSES WITH IMMIGRATION IN RANDOM ENVIRONMENTS 被引量:3
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作者 Chunmao HUANG Chen WANG Xiaoqiang WANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期49-72,共24页
Let(Z_(n))be a branching process with immigration in a random environmentξ,whereξis an independent and identically distributed sequence of random variables.We show asymptotic properties for all the moments of Z_(n) ... Let(Z_(n))be a branching process with immigration in a random environmentξ,whereξis an independent and identically distributed sequence of random variables.We show asymptotic properties for all the moments of Z_(n) and describe the decay rates of the n-step transition probabilities.As applications,a large deviation principle for the sequence log Z_(n) is established,and related large deviations are also studied. 展开更多
关键词 branching process with immigration random environment MOMENTS harmonic moments large deviations
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The Laplace Functional and Moments for Markov Branching Chains in Random Environments 被引量:1
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作者 HUDi-he ZHANGShu-lin 《Wuhan University Journal of Natural Sciences》 CAS 2005年第3期485-492,共8页
The concepts of random Markov matrix, Markov branching chain in randomenvironment (MBCRE) and Laplace functional of Markov branching chain in random environment (LFMBCRE)are introduced. The properties of LFMBCRE and t... The concepts of random Markov matrix, Markov branching chain in randomenvironment (MBCRE) and Laplace functional of Markov branching chain in random environment (LFMBCRE)are introduced. The properties of LFMBCRE and the explicit formulas of momentsof MBCRE are given. 展开更多
关键词 random Markov matrix Markov branching chain in random environment Laplacefunctional MOMENTS
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