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ABSOLUTE CONTINUITIES OF EXIT MEASURES AND TOTAL WEIGHTED OCCUPATION TIME MEASURES FOR SUPER-α-STABLE PROCESSES
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作者 张静 任艳霞 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期358-370,共13页
Suppose X is a super-α-stable process in R^d, (0 〈 α〈 2), whose branching rate function is dr, and branching mechanism is of the form ψ(z) = z^1+β (0 〈0 〈β ≤1). Let Xγ and Yγ denote the exit measur... Suppose X is a super-α-stable process in R^d, (0 〈 α〈 2), whose branching rate function is dr, and branching mechanism is of the form ψ(z) = z^1+β (0 〈0 〈β ≤1). Let Xγ and Yγ denote the exit measure and the total weighted occupation time measure of X in a bounded smooth domain D, respectively. The absolute continuities of Xγ and Yγ are discussed. 展开更多
关键词 Super-α-stable process absolute continuity exit measure total weighted occupation time measure
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Iterative Processes with Errors for Generalized Set-Valued φ-Hemi-contractive Mapping in Banach Spaces
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作者 张勇 《Journal of Southwest Jiaotong University(English Edition)》 2006年第2期194-199,共6页
A new conception of generalized set-valued Ф-hemi-contractive mapping in Banach spaces is presented. Some strong convergence theorems of Ishikawa and Mann iterative approximation with errors is proved. The results in... A new conception of generalized set-valued Ф-hemi-contractive mapping in Banach spaces is presented. Some strong convergence theorems of Ishikawa and Mann iterative approximation with errors is proved. The results in this paper improve and extend the earlier results. 展开更多
关键词 generalized set-valued Ф-hemi-contractive mapping Ishikawa and Mann iterative processes with errors q-uniformlysmooth Banach space Hausdorff metric generalized duality mapping
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Asymptotic Properties of Estimators for Ornstein-Uhlenbeck Processes with Small Symmetricα-Stable Motions
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作者 PAN Yurong JIA Chaoyong LIU Xiaoyan 《Journal of Donghua University(English Edition)》 EI CAS 2020年第4期357-364,共8页
The asymptotic behaviors for estimators of the drift parameters in the Ornstein-Uhlenbeck process driven by small symmetricα-stable motion are studied in this paper.Based on the discrete observations,the conditional ... The asymptotic behaviors for estimators of the drift parameters in the Ornstein-Uhlenbeck process driven by small symmetricα-stable motion are studied in this paper.Based on the discrete observations,the conditional least squares estimators(CLSEs)of all the parameters involved in the Ornstein–Uhlenbeck process are proposed.We establish the consistency and the asymptotic distributions of our estimators asεgoes to 0 and n goes to∞simultaneously. 展开更多
关键词 Ornstein-Uhlenbeck process symmetricα-stable motion conditional least squares estimator(CLSE) consistency asymptotic distribution
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Generalized load graphical forecasting method based on modal decomposition
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作者 Lizhen Wu Peixin Chang +1 位作者 Wei Chen Tingting Pei 《Global Energy Interconnection》 EI CSCD 2024年第2期166-178,共13页
In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power su... In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power supply.”Traditional time-series forecasting methods are no longer suitable owing to the complexity and uncertainty associated with generalized loads.From the perspective of image processing,this study proposes a graphical short-term prediction method for generalized loads based on modal decomposition.First,the datasets are normalized and feature-filtered by comparing the results of Xtreme gradient boosting,gradient boosted decision tree,and random forest algorithms.Subsequently,the generalized load data are decomposed into three sets of modalities by modal decomposition,and red,green,and blue(RGB)images are generated using them as the pixel values of the R,G,and B channels.The generated images are diversified,and an optimized DenseNet neural network was used for training and prediction.Finally,the base load,wind power,and photovoltaic power generation data are selected,and the characteristic curves of the generalized load scenarios under different permeabilities of wind power and photovoltaic power generation are obtained using the density-based spatial clustering of applications with noise algorithm.Based on the proposed graphical forecasting method,the feasibility of the generalized load graphical forecasting method is verified by comparing it with the traditional time-series forecasting method. 展开更多
关键词 Load forecasting generalized load Image processing DenseNet Modal decomposition
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The Limit Distribution of Stochastic Evolution Equations Driven by-Stable Non-Gaussian Noise
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作者 ZHAI Likai FU Hongbo 《应用数学》 北大核心 2024年第4期1180-1194,共15页
We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution co... We study the distribution limit of a class of stochastic evolution equation driven by an additive-stable Non-Gaussian process in the case of α∈(1,2).We prove that,under suitable conditions,the law of the solution converges weakly to the law of a stochastic evolution equation with an additive Gaussian process. 展开更多
关键词 Stochastic evolution equation α-stable Non-Gaussian process DISTRIBUTION
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Evaluating Traffic Congestion Using the Traffic Occupancy and Speed Distribution Relationship: An Application of Bayesian Dirichlet Process Mixtures of Generalized Linear Model 被引量:1
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作者 Emmanuel Kidando Ren Moses +1 位作者 Eren E. Ozguven Thobias Sando 《Journal of Transportation Technologies》 2017年第3期318-335,共18页
Accurate classification and prediction of future traffic conditions are essential for developing effective strategies for congestion mitigation on the highway systems. Speed distribution is one of the traffic stream p... Accurate classification and prediction of future traffic conditions are essential for developing effective strategies for congestion mitigation on the highway systems. Speed distribution is one of the traffic stream parameters, which has been used to quantify the traffic conditions. Previous studies have shown that multi-modal probability distribution of speeds gives excellent results when simultaneously evaluating congested and free-flow traffic conditions. However, most of these previous analytical studies do not incorporate the influencing factors in characterizing these conditions. This study evaluates the impact of traffic occupancy on the multi-state speed distribution using the Bayesian Dirichlet Process Mixtures of Generalized Linear Models (DPM-GLM). Further, the study estimates the speed cut-point values of traffic states, which separate them into homogeneous groups using Bayesian change-point detection (BCD) technique. The study used 2015 archived one-year traffic data collected on Florida’s Interstate 295 freeway corridor. Information criteria results revealed three traffic states, which were identified as free-flow, transitional flow condition (congestion onset/offset), and the congested condition. The findings of the DPM-GLM indicated that in all estimated states, the traffic speed decreases when traffic occupancy increases. Comparison of the influence of traffic occupancy between traffic states showed that traffic occupancy has more impact on the free-flow and the congested state than on the transitional flow condition. With respect to estimating the threshold speed value, the results of the BCD model revealed promising findings in characterizing levels of traffic congestion. 展开更多
关键词 TRAFFIC Congestion Multistate SPEED DISTRIBUTION TRAFFIC OCCUPANCY Dirichlet process Mixtures of generalized Linear Model BAYESIAN CHANGE-POINT Detection
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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search
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作者 Xiao Liu Pingting Lin +2 位作者 Fan Bu Shaoling Zhuang Shoudao Huang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期32-42,共11页
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi... The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems. 展开更多
关键词 generator optimization Gaussian process Regression(GPR) Conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation
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Proportion integral-type active disturbance rejection generalized predictive control for distillation process based on grey wolf optimization parameter tuning 被引量:1
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作者 Jia Ren Zengqiang Chen +2 位作者 Mingwei Sun Qinglin Sun Zenghui Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第9期234-244,共11页
The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limita... The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limitations in controlling distillation systems with large time delays since ADRC employs ESO and feedback control law to estimate the total disturbance of the system without considering the large time delays.This paper designs a proportion integral-type active disturbance rejection generalized predictive control(PI-ADRGPC)algorithm to control the distillation column system with large time delay.It replaces the PD controller in ADRC with a proportion integral-type generalized predictive control(PI-GPC),thereby improving the performance of control systems with large time delays.Since the proposed controller has many parameters and is difficult to tune,this paper proposes to use the grey wolf optimization(GWO)to tune these parameters,whose structure can also be used by other intelligent optimization algorithms.The performance of GWO tuned PI-ADRGPC is compared with the control performance of GWO tuned ADRC method,multi-verse optimizer(MVO)tuned PI-ADRGPC and MVO tuned ADRC.The simulation results show that the proposed strategy can track reference well and has a good disturbance rejection performance. 展开更多
关键词 Proportion integral-type active disturbance rejection generalized predictive control Grey wolf optimization Parameter tuning DISTILLATION process control PREDICTION
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A general result on precise asymptotics for linear processes of positively associated sequences 被引量:10
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作者 TAN Xi-li YANG Xiao-yun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期190-196,共7页
Let {εt; t ∈ Z^+} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2+1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^+} is a sequence of real numbers s... Let {εt; t ∈ Z^+} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2+1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^+} is a sequence of real numbers satisfying ∑j=0^∞|aj|〈∞.Define a linear process Xt=∑j=0^∞ ajεt-j,t≥1,and Sn=∑t=1^n Xt,n≥1.Assume that E|ε1|^2+δ′〈 for some δ′〉0 and μ(n)=O(n^-ρ) for some ρ〉0.This paper achieves a general law of precise asymptotics for {Sn}. 展开更多
关键词 PA sequence linear process general law precise asymptotics.
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New Algorithm Model for Processing GeneralizedDynamic Nonlinear Data Derived from Deformation Monitoring Network
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作者 LINXiangguo LIANGYong 《Geo-Spatial Information Science》 2005年第2期133-137,共5页
The processing of nonlinear data was one of hot topics in surveying and mapping field in recent years. As a result, many linear methods and nonlinear methods have been developed. But the methods for processing general... The processing of nonlinear data was one of hot topics in surveying and mapping field in recent years. As a result, many linear methods and nonlinear methods have been developed. But the methods for processing generalized nonlinear surveying and mapping data, especially for different data types and including unknown parameters with random or nonrandom, are seldom noticed. A new algorithm model is presented in this paper for processing nonlinear dynamic multiple-period and multiple-accuracy data derived from deformation monitoring network. 展开更多
关键词 deformation monitoring generalized nonlinear data processing Marquardtmethod parameter estimate
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A generalized geometric process based repairable system model with bivariate policy
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作者 MA Ning YE Jimin WANG Junyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期631-641,共11页
The maintenance model of simple repairable system is studied.We assume that there are two types of failure,namely type Ⅰ failure(repairable failure)and type Ⅱ failure(irrepairable failure).As long as the type Ⅰ fai... The maintenance model of simple repairable system is studied.We assume that there are two types of failure,namely type Ⅰ failure(repairable failure)and type Ⅱ failure(irrepairable failure).As long as the type Ⅰ failure occurs,the system will be repaired immediately,which is failure repair(FR).Between the(n-1)th and the nth FR,the system is supposed to be preventively repaired(PR)as the consecutive working time of the system reaches λ^(n-1) T,where λ and T are specified values.Further,we assume that the system will go on working when the repair is finished and will be replaced at the occurrence of the Nth type Ⅰ failure or the occurrence of the first type Ⅱ failure,whichever occurs first.In practice,the system will degrade with the increasing number of repairs.That is,the consecutive working time of the system forms a decreasing generalized geometric process(GGP)whereas the successive repair time forms an increasing GGP.A simple bivariate policy(T,N)repairable model is introduced based on GGP.The alternative searching method is used to minimize the cost rate function C(N,T),and the optimal(T,N)^(*) is obtained.Finally,numerical cases are applied to demonstrate the reasonability of this model. 展开更多
关键词 renewal reward theorem generalized geometric process(GGP) average cost rate optimal policy replacement
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ON CONVERGENCE OF A GENERALIZED P AL INTERPOLATION PROCESS
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作者 T. F. Xie (China Institute of Metrologe, China) 《Analysis in Theory and Applications》 1999年第4期15-22,共8页
Let f∈C[-1,1]and R. (r≥1 ) be the reneralized Pal iner polation polynomials satisf ying the conditions Rn, where{xk} are the roots of n-th Jacobi polynomial Pn and are the roots of In this paper,we prove that Rn... Let f∈C[-1,1]and R. (r≥1 ) be the reneralized Pal iner polation polynomials satisf ying the conditions Rn, where{xk} are the roots of n-th Jacobi polynomial Pn and are the roots of In this paper,we prove that Rn holds uniformly on [0,1]. 展开更多
关键词 Math AL ON CONVERGENCE OF A generalized P AL INTERPOLATION process
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Generativity of Self-Organizing Processes and Their Correlative Description in Terms of a Formal Language of Meta-Ordinal Generative Nature, in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第10期3159-3202,共44页
The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be mode... The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be modeled using the Maximum Ordinality Principle and its associated formal language, known as the “Incipient” Differential Calculus (IDC). 展开更多
关键词 Maximum Ordinality Principle Solution to the “Three-Body Problem” generativity of Self-Organizing processes Formal Language of Ordinal generativity Formal Language of Meta-Ordinal generativity
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Efficiency of Some Estimators for a Generalized Poisson Autoregressive Process of Order 1
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作者 Louis G. Doray Andrew Luong El-Halla Najem 《Open Journal of Statistics》 2016年第4期637-650,共14页
Various models have been proposed in the literature to study non-negative integer-valued time series. In this paper, we study estimators for the generalized Poisson autoregressive process of order 1, a model developed... Various models have been proposed in the literature to study non-negative integer-valued time series. In this paper, we study estimators for the generalized Poisson autoregressive process of order 1, a model developed by Alzaid and Al-Osh [1]. We compare three estimation methods, the methods of moments, quasi-likelihood and conditional maximum likelihood and study their asymptotic properties. To compare the bias of the estimators in small samples, we perform a simulation study for various parameter values. Using the theory of estimating equations, we obtain expressions for the variance-covariance matrices of those three estimators, and we compare their asymptotic efficiency. Finally, we apply the methods derived in the paper to a real time series. 展开更多
关键词 Discrete Time Series Autoregressive process Moment Estimator QUASI-LIKELIHOOD EFFICIENCY generalized Poisson Quasi Binomial Distribution
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ON THE BASIC REPRODUCTION NUMBER OF GENERAL BRANCHING PROCESSES 被引量:1
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作者 蓝国烈 马志明 孙苏勇 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1081-1094,共14页
Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual ... Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual CMJ processes. We discuss also some properties of the extinction probability and the generating operator of general branching processes. As an application in epidemics, in the final section we suggest a generalization of SIR model which can describe infectious diseases transmission in an inhomogeneous population. 展开更多
关键词 general branching process extinction probability reproduction kernel spectral radius TNC condition basic reproduction number SIR model
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Integral Operator Solving Process of the Boundary Value Problem of Abstract Kinetic Equation with the First Kind of Critical Parameter and Generalized Periodic Boundary Conditions
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作者 YU De-jian 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期110-117,共8页
In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space whic... In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space which consists of functions with vector valued in a general Banach space, and then describe the solution of these abstract boundary value problem by the abstract linear integral operator of Volterra type. We call this process the integral operator solving process. 展开更多
关键词 abstract kinetic equation with the first kind of critical parameter boundary value problem of abstract kinetic equation generalized periodic boundary conditions abstract linear integral operator of Volterra type integral operator solving process
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N指标d维广义α-stable过程的逗留时 被引量:2
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作者 郑水草 胡迪鹤 《武汉大学学报(理学版)》 CAS CSCD 北大核心 2002年第3期274-280,共7页
研究了一类新过程——广义α-stable过程,它包含了N指标d维α-stable过程和N指标d维广义布朗单.导出了一些与该过程的逗留时有关的小概率事件的界.这些界有助于确定该过程的样本轨道的确切的Hausdorff测度函数.
关键词 N指标 D维 广义Α-stable过程 逗留时 稳定过程 广义布朗单
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广义α-stable过程局部时增量的Hlder律 被引量:2
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作者 郑水草 庄兴无 《数学物理学报(A辑)》 CSCD 北大核心 1999年第4期415-423,共9页
该文证明了广义a-stable过程局部时增量的Holder律,推广了N指标d维α-stable过程和N指标d维广义BrownianSheet的相应结果.
关键词 局部时 局部增量 α-stable过程 Hoelder律 广义
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广义α-stable过程的自相交局部时 被引量:1
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作者 陈振龙 刘三阳 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2004年第2期310-316,共7页
研究了N指标d维广义α stable过程自相交局部时的存在性和联合连续性,给出了其相交局部时平方可积和联合连续的一个充分条件,其结论推广了N指标d维α stable过程和N指标d维广义BrownianSheet的相应结果.
关键词 广义Α-stable过程 自相交局部时 广义布朗单 联合连续 BROWN运动 样本轨道
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N指标d维广义α-stable过程的局部时 被引量:2
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作者 郑水草 《福建师范大学学报(自然科学版)》 CAS CSCD 1999年第2期16-20,共5页
研究了一类新过程——广义α-stable过程,它包含了N指标d维α-stable过程和N指标d维广义布朗单.证明了该过程的局部时的存在性、联合连续性和可微性.
关键词 局部时 稳定过程 广义 联合连续 α-稳定过程
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