Electromechanical product's reliability is affected by uncertainty as well as performance degeneration during its life cycle.The present reliability and performance integrating modeling methods have obvious defici...Electromechanical product's reliability is affected by uncertainty as well as performance degeneration during its life cycle.The present reliability and performance integrating modeling methods have obvious deficiencies in long period reliability analysis and assessment when applied to such system.A novel integrating modeling method based on physics of failure(PoF)and a simulation algorithm that considers uncertainty and degeneration are proposed in this paper to compute maintenance free operation period or maintenance free operation period survivability which is used to assess long period reliability of system.Furthermore,the concept design of this kind of software based on the above theory is also introduced.A case study of servo valve demonstrates the feasibility of the method and usability of the software in this research.展开更多
现有的基于失效物理(physics of failure,PoF)模型的可靠性预计只能计算电子产品在寿命周期内经历单一典型任务剖面的失效时间。本文提出了一种基于失效物理模型,并利用蒙特卡罗仿真定量分析电子产品在寿命周期内实际经历多任务剖面的...现有的基于失效物理(physics of failure,PoF)模型的可靠性预计只能计算电子产品在寿命周期内经历单一典型任务剖面的失效时间。本文提出了一种基于失效物理模型,并利用蒙特卡罗仿真定量分析电子产品在寿命周期内实际经历多任务剖面的可靠性水平的新方法。将该方法应用于某机载电子设备的平均失效前时间(mean time to failure,MTTF)的计算,建立失效率和可靠度的时间函数,与目前国内工程实践中常用的失效率经验模型法以及设备可靠性强化试验的结果进行了对比分析。结果表明,该方法不仅可以计算可靠性参数,而且通过分析与计算过程可发现设计薄弱环节与可靠性参数的定量关系,有效指导设计改进。展开更多
软件定义网络(SDN)和内容中心网络(CCN)是非常有前景的下一代互联网架构,而结合了二者特性的新架构—软件定义内容网络(SDCN)也已经引起了广泛关注.在基于协议无感知转发(POF)实现的SDCN中,通过控制器收集网络拓扑信息,构建分层存储模型...软件定义网络(SDN)和内容中心网络(CCN)是非常有前景的下一代互联网架构,而结合了二者特性的新架构—软件定义内容网络(SDCN)也已经引起了广泛关注.在基于协议无感知转发(POF)实现的SDCN中,通过控制器收集网络拓扑信息,构建分层存储模型,在网络总缓存空间固定的约束条件下,引入节点价值解决缓存空间分配问题.在此基础上,提出基于节点价值的缓存决策CDV(Cache Decision based on Value),以及基于内容热度的缓存替换策略CRP(Cache Replacement based on Popularity),实验结果表明,基于分层模型的缓存管理策略使得网络缓存性能提高.展开更多
基金National Natural Science Foundation of China(No.61304218)Beijing Natural Science Foundation,China(No.3153027)
文摘Electromechanical product's reliability is affected by uncertainty as well as performance degeneration during its life cycle.The present reliability and performance integrating modeling methods have obvious deficiencies in long period reliability analysis and assessment when applied to such system.A novel integrating modeling method based on physics of failure(PoF)and a simulation algorithm that considers uncertainty and degeneration are proposed in this paper to compute maintenance free operation period or maintenance free operation period survivability which is used to assess long period reliability of system.Furthermore,the concept design of this kind of software based on the above theory is also introduced.A case study of servo valve demonstrates the feasibility of the method and usability of the software in this research.
文摘现有的基于失效物理(physics of failure,PoF)模型的可靠性预计只能计算电子产品在寿命周期内经历单一典型任务剖面的失效时间。本文提出了一种基于失效物理模型,并利用蒙特卡罗仿真定量分析电子产品在寿命周期内实际经历多任务剖面的可靠性水平的新方法。将该方法应用于某机载电子设备的平均失效前时间(mean time to failure,MTTF)的计算,建立失效率和可靠度的时间函数,与目前国内工程实践中常用的失效率经验模型法以及设备可靠性强化试验的结果进行了对比分析。结果表明,该方法不仅可以计算可靠性参数,而且通过分析与计算过程可发现设计薄弱环节与可靠性参数的定量关系,有效指导设计改进。
文摘软件定义网络(SDN)和内容中心网络(CCN)是非常有前景的下一代互联网架构,而结合了二者特性的新架构—软件定义内容网络(SDCN)也已经引起了广泛关注.在基于协议无感知转发(POF)实现的SDCN中,通过控制器收集网络拓扑信息,构建分层存储模型,在网络总缓存空间固定的约束条件下,引入节点价值解决缓存空间分配问题.在此基础上,提出基于节点价值的缓存决策CDV(Cache Decision based on Value),以及基于内容热度的缓存替换策略CRP(Cache Replacement based on Popularity),实验结果表明,基于分层模型的缓存管理策略使得网络缓存性能提高.
