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双区间删失数据下基于Stochastic EM算法的比例优势模型的估计研究
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作者 王淑影 李红伟 赵波 《应用概率统计》 北大核心 2025年第3期434-447,共14页
潜伏期是流行病学、疾病进展研究等关心的重要指标之一,对疾病防控及治疗具有重要作用.潜伏期是从病毒感染到产生症状这两个事件发生时间的间隔时间,并且这两个发生时间均有可能出现删失,于是产生了双区间删失数据.在双区间删失数据的... 潜伏期是流行病学、疾病进展研究等关心的重要指标之一,对疾病防控及治疗具有重要作用.潜伏期是从病毒感染到产生症状这两个事件发生时间的间隔时间,并且这两个发生时间均有可能出现删失,于是产生了双区间删失数据.在双区间删失数据的研究中,后续时间仅考虑发生右删失或区间删失的研究很多,考虑右删失和区间删失同时存在的研究成果相对较少;此外研究方法大多基于Cox模型.本文在后续时间同时存在右删失和区间删失的这类双区间删失数据下建立比例优势模型,利用Stochastic EM算法处理双区间删失数据并进行极大似然估计.通过模拟研究评估了所提方法在有限样本下的优良性,接着利用该方法分析了AIDS数据. 展开更多
关键词 双区间删失数据 比例优势模型 stochastic EM算法 拒绝抽样
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Stochastic Periodic Solutions for Two Populations Game Models with Impulses
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作者 HOU Meiting QIU Xiaoling 《应用数学》 北大核心 2025年第2期453-467,共15页
The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding sto... The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding stochastic and impulse. For the stochastic model without impulses, the existence and uniqueness of solution, and the existence of positive periodic solutions are proved, and a sufficient condition for strategy extinction is given. For the stochastic model with impulses, the existence of positive periodic solutions is proved. Numerical results show that noise and impulses directly affect the model, but the periodicity of the model does not change. 展开更多
关键词 Periodic solution stochastic game IMPULSES Strategy extinct
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Learning the parameters of a class of stochastic Lotka-Volterra systems with neural networks
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作者 WANG Zhanpeng WANG Lijin 《中国科学院大学学报(中英文)》 北大核心 2025年第1期20-25,共6页
In this paper,we propose a neural network approach to learn the parameters of a class of stochastic Lotka-Volterra systems.Approximations of the mean and covariance matrix of the observational variables are obtained f... In this paper,we propose a neural network approach to learn the parameters of a class of stochastic Lotka-Volterra systems.Approximations of the mean and covariance matrix of the observational variables are obtained from the Euler-Maruyama discretization of the underlying stochastic differential equations(SDEs),based on which the loss function is built.The stochastic gradient descent method is applied in the neural network training.Numerical experiments demonstrate the effectiveness of our method. 展开更多
关键词 stochastic Lotka-Volterra systems neural networks Euler-Maruyama scheme parameter estimation
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Some studies on stochastic optimization based quantitative risk management
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作者 HU Zhaolin 《运筹学学报(中英文)》 北大核心 2025年第3期135-159,共25页
Risk management often plays an important role in decision making un-der uncertainty.In quantitative risk management,assessing and optimizing risk metrics requires eficient computing techniques and reliable theoretical... Risk management often plays an important role in decision making un-der uncertainty.In quantitative risk management,assessing and optimizing risk metrics requires eficient computing techniques and reliable theoretical guarantees.In this pa-per,we introduce several topics on quantitative risk management and review some of the recent studies and advancements on the topics.We consider several risk metrics and study decision models that involve the metrics,with a main focus on the related com-puting techniques and theoretical properties.We show that stochastic optimization,as a powerful tool,can be leveraged to effectively address these problems. 展开更多
关键词 stochastic optimization quantitative risk management risk measure computing technique statistical property
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Smoluchowski-Kramers Approximation for Stochastic Differential Equations under Discretization
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作者 Li Ge 《应用概率统计》 北大核心 2025年第4期622-635,共14页
This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–M... This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–Maruyama discretization and derive its convergence rate.In particular,the solution of the discretized system converges to the solution of the first-order limit equation in the mean-square sense,and this convergence is independent of the order in which the mass parameterμand the step size h tend to zero. 展开更多
关键词 stochastic differential equations Smoluchowski-Kramers approximation driftimplicit Euler-Maruyama scheme convergence rate
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Selective maintenance decision optimization for systems executing multi-mission under stochastic mission duration
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作者 MA Weining DONG Enzhi +1 位作者 LI Hua ZHAO Mei 《Journal of Systems Engineering and Electronics》 2025年第1期209-223,共15页
This paper investigates the selective maintenance o systems that perform multi-mission in succession. Selective maintenance is performed on systems with limited break time to improve the success of the next mission. I... This paper investigates the selective maintenance o systems that perform multi-mission in succession. Selective maintenance is performed on systems with limited break time to improve the success of the next mission. In general, the duration of the mission is stochastic. However, existing studies rarely take into account system availability and the repairpersons with different skill levels. To solve this problem, a new multi-mission selective maintenance and repairpersons assignment model with stochastic duration of the mission are developed. To maximize the minimum phase-mission reliability while meeting the minimum system availability, the model is transformed into an optimization problem subject to limited maintenance resources. The optimization is then realized using an analytical method based on a self-programming function and a Monte Carlo simulation method, respectively. Finally, the validity of the model and solution method approaches are verified by numerical arithmetic examples. Comparative and sensitivity analyses are made to provide proven recommendations for decision-makers. 展开更多
关键词 multi-mission system selective maintenance problem stochastic duration Monte Carlo simulation AVAILABILITY
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Reliability of multi-dimensional network systems with nodes having stochastic connection ranges
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作者 FU Yuqiang MA Xiaoyang ZHAO Fei 《Journal of Systems Engineering and Electronics》 2025年第4期1017-1023,共7页
This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with... This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with one source element and multiple sink elements is considered first.Each element can con-nect with other elements within a stochastic connection ranges.The system is regarded as successful as long as the source ele-ment remains connected with all sink elements.An importance measure is proposed to evaluate the performance of non-source elements.Furthermore,to calculate the system reliability and the element importance measure,a multi-valued decision diagram based approach is structured and its complexity is analyzed.Finally,a numerical example about the signal transfer station system is illustrated to analyze the system reliability and the ele-ment importance measure. 展开更多
关键词 multi-dimensional network multi-valued decision diagram stochastic connection range reliability analysis impor-tance measure.
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Consensus of multi-vehicle cooperative attack with stochastic multi-hop time-varying delay and actuator fault 被引量:2
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作者 CAI Guangbin ZHAO Yushan +1 位作者 ZHAO Yang HU Changhua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期228-242,共15页
A consensus-distributed fault-tolerant(CDFT)control law is proposed for a class of leader-following multi-vehicle cooperative attack(MVCA)systems in this paper.In particular,the switching communication topologies,stoc... A consensus-distributed fault-tolerant(CDFT)control law is proposed for a class of leader-following multi-vehicle cooperative attack(MVCA)systems in this paper.In particular,the switching communication topologies,stochastic multi-hop timevarying delays,and actuator faults are considered,which may lead to system performance degradation or on certain occasions even cause system instability.Firstly,the estimator of actuator faults for the following vehicle is designed to identify the actuator faults under a fixed topology.Then the CDFT control protocol and trajectory following error are derived by the relevant content of Lyapunov stability theory,the graph theory,and the matrix theory.The CDFT control protocol is proposed in the same manner,where a more realistic scenario is considered,in which the maximum trajectory following error and information on the switching topologies during the cooperative attack are available.Finally,numerical simulation are carried out to indicate that the proposed distributed fault-tolerant(DFT)control law is effective. 展开更多
关键词 leader-following multi-vehicle cooperative attack(MVCA) switching topology fault-tolerant control stochastic multi-hop time-varying delay stochastic actuator fault
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Passivity analysis for uncertain stochastic neural networks with discrete interval and distributed time-varying delays 被引量:3
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作者 P.Balasubramaniam G.Nagamani 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期688-697,共10页
The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the ... The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the delay is assumed to be time-varying and belongs to a given interval,which means that the lower and upper bounds of interval time-varying delays are available.By constructing proper Lyapunov-Krasovskii functional and employing a combination of the free-weighting matrix method and stochastic analysis technique,new delay-dependent passivity conditions are derived in terms of linear matrix inequalities(LMIs).Finally,numerical examples are given to show the less conservatism of the proposed conditions. 展开更多
关键词 linear matrix inequality(LMI) stochastic neural network PASSIVITY interval time-varying delay Lyapunov method.
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Robust H_∞ control for neutral stochastic uncertain systems with time-varying delay 被引量:3
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作者 Guici Chen Xiaoping Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期658-665,共8页
The problem of robust H_∞ control for uncertain neutral stochastic systems with time-varying delay is discussed.The parameter uncertaintie is assumed to be time varying norm-bounded.First,the stochastic robust stabil... The problem of robust H_∞ control for uncertain neutral stochastic systems with time-varying delay is discussed.The parameter uncertaintie is assumed to be time varying norm-bounded.First,the stochastic robust stabilization of the stochastic system without disturbance input is investigated by nonlinear matrix inequality method.Then,a full-order stochastic dynamic output feedback controller is designed by solving a bilinear matrix inequality(BMI),which ensures a prescribed stochastic robust H_∞ performance level for the resulting closed-loop system with nonzero disturbance input and for all admissible uncertainties.An illustrative example is provided to show the feasibility of the controller and the potential of the proposed technique. 展开更多
关键词 stochastic robust H_∞ control neutral stochastic system uncertain system stochastic dynamic output feedback controller bilinear matrix inequality(BMI).
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Guaranteed Quadratic Stabilization of Certain Time-Varying Large-Scale Delay It Stochastic Systems 被引量:1
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作者 Jin Yansheng & Xu Yumin (Dept. of Mathematics and Physics, Yanshan University, Qinhuangdao 066004, P. R. China) Deng Feiqi (Dept. of Automatic Control Engineering, South China University of Technology, Guangzhou 510641, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第3期35-39,共5页
In this paper, we investigate the decentralized stabilization of some time-varying uncertain large-scale stochastic systems with delays under matching conditions. A type of decentralized controllers with guaranteed s... In this paper, we investigate the decentralized stabilization of some time-varying uncertain large-scale stochastic systems with delays under matching conditions. A type of decentralized controllers with guaranteed stabilization and sub-optimality are also given. 展开更多
关键词 stochastic systems Uncertainty Stabilization.
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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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New criteria on delayed state feedback stabilization for stochastic systems with time-varying delay
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作者 Shiguo Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第3期519-527,共9页
The problems of robust exponential stability in mean square and delayed state feedback stabilization for uncertain stochastic systems with time-varying delay are studied. By using Jensen's integral inequality and com... The problems of robust exponential stability in mean square and delayed state feedback stabilization for uncertain stochastic systems with time-varying delay are studied. By using Jensen's integral inequality and combining with the free weighting matrix approach, new delay-dependent stability conditions and delayed state feedback stabilization criteria are obtained in terms of linear matrix inequalities. Meanwhile, the proposed delayed state feedback stabilization criteria are more convenient in application than the existing ones since fewer tuning parameters are involved. Numerical examples are given to illustrate the effectiveness of the proposed methods. 展开更多
关键词 stochastic system time-varying delay delay-depen- dent exponential stability delayed state feedback stabilization.
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Delay-dependent exponential stability of impulsive stochastic systems with time-varying delay
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作者 Pei Cheng Feiqi Deng Yunjian Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期799-809,共11页
The problem of delay-dependent exponential stability is investigated for impulsive stochastic systems with time-varying delay. Although the exponential stability of impulsive stochastic delay systems has been discusse... The problem of delay-dependent exponential stability is investigated for impulsive stochastic systems with time-varying delay. Although the exponential stability of impulsive stochastic delay systems has been discussed by several authors, few works have been done on delay-dependent exponential stability of impulsive stochastic delay systems. Firstly, the Lyapunov-Krasovskii functional method combing the free-weighting matrix approach is applied to investigate this problem. Some delay-dependent mean square exponential stability criteria are derived in terms of linear matrix inequalities. In particular, the estimate of the exponential convergence rate is also provided, which depends on system parameters and impulsive effects. The obtained results show that the system will stable if the impulses' frequency and amplitude are suitably related to the increase or decrease of the continuous flows, and impulses may be used as controllers to stabilize the underlying stochastic system. Numerical examples are given to show the effectiveness of the results. 展开更多
关键词 impulsive stochastic systems time-varying delay exponential stability linear matrix inequality (LMI).
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Mean-square exponential stability for stochastic time-varying delay systems with Markovian jumping parameters:a delay decomposition approach
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作者 Li Ma Feipeng Da 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期816-824,共9页
The mean-square exponential stability problem is investigated for a class of stochastic time-varying delay systems with Markovian jumping parameters. By decomposing the delay interval into multiple equidistant subinte... The mean-square exponential stability problem is investigated for a class of stochastic time-varying delay systems with Markovian jumping parameters. By decomposing the delay interval into multiple equidistant subintervals, a new delay-dependent and decay-rate-dependent criterion is presented based on constructing a novel Lyapunov functional and employing stochastic analysis technique. Besides, the decay rate has no conventional constraint and can be selected according to different practical conditions. Finally, two numerical examples are provided to show that the obtained result has less conservatism than some existing ones in the literature. 展开更多
关键词 stochastic systems time-varying delay Markov chain linear matrix inequality (LMI).
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Improved results on passivity analysis of discrete-time stochastic neural networks with time-varying delay
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作者 于建江 张侃健 费树岷 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期63-67,共5页
The problem of passivity analysis for a class of discrete-time stochastic neural networks (DSNNs) with time-varying interval delay was investigated. The delay-dependent sufficient criteria were derived in terms of lin... The problem of passivity analysis for a class of discrete-time stochastic neural networks (DSNNs) with time-varying interval delay was investigated. The delay-dependent sufficient criteria were derived in terms of linear matrix inequalities (LMIs). The results are shown to be generalization of some previous results and are less conservative than the existing works. Meanwhile, the computational complexity of the obtained stability conditions is reduced because less variables are involved. A numerical example is given to show the effectiveness and the benefits of the proposed method. 展开更多
关键词 PASSIVITY DISCRETE-TIME stochastic neural networks (DSNNs) INTERVAL delay linear matrix INEQUALITIES (LMIs)
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Adaptive NN stabilization for stochastic systems with discrete and distributed time-varying delays
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作者 Jing Li Junmin Li Yuli Xiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期954-966,共13页
A new adaptive neural network(NN) output-feedback stabilization controller is investigated for a class of uncertain stochastic nonlinear strict-feedback systems with discrete and distributed time-varying delays and ... A new adaptive neural network(NN) output-feedback stabilization controller is investigated for a class of uncertain stochastic nonlinear strict-feedback systems with discrete and distributed time-varying delays and unknown nonlinear functions in both drift and diffusion terms.First,an extensional stability notion and the related criterion are introduced.Then,a nonlinear observer to estimate the unmeasurable states is designed,and a systematic backstepping procedure to design an adaptive NN output-feedback controller is proposed such that the closed-loop system is stable in probability.The effectiveness of the proposed control scheme is demonstrated via a numerical example. 展开更多
关键词 distributed delay output-feedback stabilization nonlinear observer stochastic nonlinear strict-feedback system adaptive neural network control(ANNC).
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Delay-dependent Robust Stability for Uncertain Stochastic Systems with Interval Time-varying Delay 被引量:5
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作者 ZHANG Yan HE Yong WU Min 《自动化学报》 EI CSCD 北大核心 2009年第5期577-582,共6页
关键词 随机系统 稳定性 自动化 分析
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Parameter estimation of the stochastic AMR model and its application to the study of several strong earthquakes 被引量:3
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作者 王丽凤 马丽 +1 位作者 DavidVere-Jones 陈时军 《地震学报》 CSCD 北大核心 2004年第2期162-173,共12页
Based on the stochastic AMR model, this paper constructs man-made earthquake catalogues to investigate the property of parameter estimation of the model. Then the stochastic AMR model is applied to the study of severa... Based on the stochastic AMR model, this paper constructs man-made earthquake catalogues to investigate the property of parameter estimation of the model. Then the stochastic AMR model is applied to the study of several strong earthquakes in China and New Zealand. Akaikes AIC criterion is used to discriminate whether an accelerating mode of earthquake activity precedes those events or not. Finally, regional accelerating seismic activity and possible prediction approach for future strong earthquakes are discussed. 展开更多
关键词 随机AMR模型 参数估计 最大似然法 AIC准则 强震 地震预报 地震活动
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基于Stochastic Kriging的柔性机翼稳健性优化设计 被引量:7
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作者 刘艳 白俊强 +2 位作者 华俊 刘南 王波 《西北工业大学学报》 EI CAS CSCD 北大核心 2015年第6期906-912,共7页
采用随机代理模型方法对柔性机翼气动外形进行稳健性优化设计。相比确定性优化设计,稳健性设计能够考虑设计变量和参数的扰动,保持设计结果在不确定性影响下的性能稳定。采用高精度的气动/结构耦合求解器(耦合Navier-Stokes方程和结构... 采用随机代理模型方法对柔性机翼气动外形进行稳健性优化设计。相比确定性优化设计,稳健性设计能够考虑设计变量和参数的扰动,保持设计结果在不确定性影响下的性能稳定。采用高精度的气动/结构耦合求解器(耦合Navier-Stokes方程和结构静力学方程)分析柔性机翼的变形情况和气动效率。为了提高优化效率,建立随机Kriging(Stochastic Kriging,SK)代理模型,将确定性的Kriging代理模型发展到随机空间,通过有限次输入得到数据的固有不确定性。对柔性M6机翼的气动外形进行稳健性优化设计,结果表明:相比确定性代理模型的稳健性优化结果,应用随机代理模型的优化结果的设计点阻力系数减小2.8 counts,在可变马赫数范围内阻力系数均值减小3.2 counts,优化结果具有较高的设计点气动效率和阻力发散特性,并且优化后构型的翼根弯矩有明显减小,体现随机代理模型在稳健性优化设计系统中的优势,同时也说明建立的SK代理模型具有较高的预测精度。 展开更多
关键词 柔性机翼 稳健性优化 静气动弹性力学 随机Kriging代理模型 NAVIER-STOKES方程
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