随着电网智能化的发展,配电网已逐渐由传统的物理系统发展为信息-物理融合配电系统,信息技术的广泛应用在大幅提高配电网运行效率和可靠性的同时,也带来了新的运行风险。该文根据配电网中分布式智能终端与主站协调控制的特点,深入分析...随着电网智能化的发展,配电网已逐渐由传统的物理系统发展为信息-物理融合配电系统,信息技术的广泛应用在大幅提高配电网运行效率和可靠性的同时,也带来了新的运行风险。该文根据配电网中分布式智能终端与主站协调控制的特点,深入分析配电网故障处理过程中信息系统异常事件对物理系统的影响后果,构建了计及信息元件损坏以及传输延时、传输错误等信息故障形式的信息-物理融合的配电网可靠性评估模型。最后,以IEEE-RBTS Bus 6配电网的主馈线F4为例,展示了基于所提模型的配电系统可靠性评估过程,验证了所提模型的可行性。展开更多
随着计算机与物理环境的交互日益密切,信息-物理融合系统(cyber-physical system,简称CPS)在健康医疗、航空电子、智能建筑等领域具有广泛的应用前景,CPS的正确性、可靠性分析已引起人们的广泛关注.统计模型检测(statistical model chec...随着计算机与物理环境的交互日益密切,信息-物理融合系统(cyber-physical system,简称CPS)在健康医疗、航空电子、智能建筑等领域具有广泛的应用前景,CPS的正确性、可靠性分析已引起人们的广泛关注.统计模型检测(statistical model checking,简称SMC)技术能够对CPS进行有效验证,并为系统的性能提供定量评估.然而,随着系统规模的日益扩大,如何提高统计模型检测技术验证CPS的效率,是目前所面临的主要困难之一.针对此问题,首先对现有SMC技术进行实验分析,总结各种SMC技术的受限适用范围和性能缺陷,并针对贝叶斯区间估计算法(Bayesian interval estimate,简称BIE)在实际概率接近0.5时需要大量路径才能完成验证的缺陷,提出一种基于抽象和学习的统计模型检测方法 AL-SMC.该方法采用主成分分析、前缀树约减等技术对仿真路径进行学习和抽象,以减少样本空间;然后,提出了一个面向CPS的自适应SMC算法框架,可根据不同的概率区间自动选择AL-SMC算法或者BIE算法,有效应对不同情况下的验证问题;最后,结合经典案例进行实验分析,实验结果表明,自适应SMC算法框架能够在一定误差范围内有效提高CPS统计模型检测的效率,为CPS的分析验证提供了一种有效的途径.展开更多
Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on mu...Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on multiprocessor platforms with instance skipping was formulated based on the(m,k)-constrained model.A partitioned scheduling method SC-AD was proposed to solve the problem.SC-AD uses a derived sufficient schedulability condition to calculate the initial value of m for each sensor transaction.It then partitions the transactions among the processors in a balanced way.To further reduce the average relative invalid time of real-time data,SC-AD judiciously increases the values of m for transactions assigned to each processor.Experiment results show that SC-AD outperforms the baseline methods in terms of the average relative invalid time and the average valid ratio under different system workloads.展开更多
文摘随着电网智能化的发展,配电网已逐渐由传统的物理系统发展为信息-物理融合配电系统,信息技术的广泛应用在大幅提高配电网运行效率和可靠性的同时,也带来了新的运行风险。该文根据配电网中分布式智能终端与主站协调控制的特点,深入分析配电网故障处理过程中信息系统异常事件对物理系统的影响后果,构建了计及信息元件损坏以及传输延时、传输错误等信息故障形式的信息-物理融合的配电网可靠性评估模型。最后,以IEEE-RBTS Bus 6配电网的主馈线F4为例,展示了基于所提模型的配电系统可靠性评估过程,验证了所提模型的可行性。
基金Project(2020JJ4032)supported by the Hunan Provincial Natural Science Foundation of China。
文摘Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on multiprocessor platforms with instance skipping was formulated based on the(m,k)-constrained model.A partitioned scheduling method SC-AD was proposed to solve the problem.SC-AD uses a derived sufficient schedulability condition to calculate the initial value of m for each sensor transaction.It then partitions the transactions among the processors in a balanced way.To further reduce the average relative invalid time of real-time data,SC-AD judiciously increases the values of m for transactions assigned to each processor.Experiment results show that SC-AD outperforms the baseline methods in terms of the average relative invalid time and the average valid ratio under different system workloads.
