In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HH...In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HHTME), which combines the testabi- lity structure model (TSM) with the testability Bayesian networks model (TBNM), is presented. Firstly, the testability network topo- logy of complex equipment is built by using the hierarchical hybrid testability modeling method. Secondly, the prior conditional prob- ability distribution between network nodes is determined through expert experience. Then the Bayesian method is used to update the conditional probability distribution, according to history test information, virtual simulation information and similar product in- formation. Finally, the learned hierarchical hybrid testability model (HHTM) is used to estimate the testability of equipment. Compared with the results of other modeling methods, the relative deviation of the HHTM is only 0.52%, and the evaluation result is the most accu rate.展开更多
Underground space utilization and exploration is an irreversible trend for promoting sustainable development especially in megacities.Geotechnical engineering safety is always one of the most important issues in all p...Underground space utilization and exploration is an irreversible trend for promoting sustainable development especially in megacities.Geotechnical engineering safety is always one of the most important issues in all phases,including planning,design, construction and operation,of the underground project.Engineering geological and hydro-geological characteristics of the foundation rock mass展开更多
现有大跨径桥梁有限元模型修正(finite element model updating,FEMU)方法一般未考虑运营荷载对结构动力特性的影响,导致修正后模型的参数变异性大。鉴于此,提出了一种考虑运营荷载的层次贝叶斯有限元模型修正方法,该方法包含考虑温度...现有大跨径桥梁有限元模型修正(finite element model updating,FEMU)方法一般未考虑运营荷载对结构动力特性的影响,导致修正后模型的参数变异性大。鉴于此,提出了一种考虑运营荷载的层次贝叶斯有限元模型修正方法,该方法包含考虑温度和交通荷载的概率参数修正、概率响应预测和结构状态评估。首先,根据监测数据的相关性分析结果确定了计算理论频率时需要考虑的荷载。随后,建立了温度-弹性模量线性关系,并基于动态称重(weigh-in-motion,WIM)数据,提出一种车辆荷载估计方法,以在有限元模型中定量考虑运营荷载对结构频率的影响。同时,引入两阶段马尔科夫链蒙特卡洛(Markov chain Monte Carlo,MCMC)采样方法和响应面代理模型,以提高概率模型修正的计算速率。该方法在一座采集了两年监测数据的大跨径拱桥上得到了验证。结果表明,在考虑运营荷载、参数不确定性和建模误差后,实测频率基本处于预测频率的95%置信区间内。最后,基于实测响应和预测响应置信区间提出了一个结构状态指标,并利用该指标检测出该桥的路面铺装更换过程。展开更多
针对当前装备体系(system of systems,SoS)任务建模研究深入程度不足问题,提出装备SoS使命任务的概念模型和描述模型,在此基础上,首先对各层级任务的任务线程进行分析与规划,改进传统Petri网,提出一种基于层次确定与随机Petri网(hierarc...针对当前装备体系(system of systems,SoS)任务建模研究深入程度不足问题,提出装备SoS使命任务的概念模型和描述模型,在此基础上,首先对各层级任务的任务线程进行分析与规划,改进传统Petri网,提出一种基于层次确定与随机Petri网(hierarchical deterministic and stochastic Petri nets,HDSPN)的装备SoS任务线程建模方法,构建面向多层级使命任务的装备SoS任务线程模型。然后,结合基于可达性分析算法(reachability analysis algorithm,RAA)的装备SoS总体任务成功性仿真评估算法,启动仿真模型运行,实现对装备SoS总体任务成功性的有效评估,并通过案例分析,验证了模型的适用性。展开更多
基金supported by the National Defense Pre-research Foundation of China(51327030104)
文摘In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HHTME), which combines the testabi- lity structure model (TSM) with the testability Bayesian networks model (TBNM), is presented. Firstly, the testability network topo- logy of complex equipment is built by using the hierarchical hybrid testability modeling method. Secondly, the prior conditional prob- ability distribution between network nodes is determined through expert experience. Then the Bayesian method is used to update the conditional probability distribution, according to history test information, virtual simulation information and similar product in- formation. Finally, the learned hierarchical hybrid testability model (HHTM) is used to estimate the testability of equipment. Compared with the results of other modeling methods, the relative deviation of the HHTM is only 0.52%, and the evaluation result is the most accu rate.
文摘Underground space utilization and exploration is an irreversible trend for promoting sustainable development especially in megacities.Geotechnical engineering safety is always one of the most important issues in all phases,including planning,design, construction and operation,of the underground project.Engineering geological and hydro-geological characteristics of the foundation rock mass
文摘现有大跨径桥梁有限元模型修正(finite element model updating,FEMU)方法一般未考虑运营荷载对结构动力特性的影响,导致修正后模型的参数变异性大。鉴于此,提出了一种考虑运营荷载的层次贝叶斯有限元模型修正方法,该方法包含考虑温度和交通荷载的概率参数修正、概率响应预测和结构状态评估。首先,根据监测数据的相关性分析结果确定了计算理论频率时需要考虑的荷载。随后,建立了温度-弹性模量线性关系,并基于动态称重(weigh-in-motion,WIM)数据,提出一种车辆荷载估计方法,以在有限元模型中定量考虑运营荷载对结构频率的影响。同时,引入两阶段马尔科夫链蒙特卡洛(Markov chain Monte Carlo,MCMC)采样方法和响应面代理模型,以提高概率模型修正的计算速率。该方法在一座采集了两年监测数据的大跨径拱桥上得到了验证。结果表明,在考虑运营荷载、参数不确定性和建模误差后,实测频率基本处于预测频率的95%置信区间内。最后,基于实测响应和预测响应置信区间提出了一个结构状态指标,并利用该指标检测出该桥的路面铺装更换过程。
文摘针对当前装备体系(system of systems,SoS)任务建模研究深入程度不足问题,提出装备SoS使命任务的概念模型和描述模型,在此基础上,首先对各层级任务的任务线程进行分析与规划,改进传统Petri网,提出一种基于层次确定与随机Petri网(hierarchical deterministic and stochastic Petri nets,HDSPN)的装备SoS任务线程建模方法,构建面向多层级使命任务的装备SoS任务线程模型。然后,结合基于可达性分析算法(reachability analysis algorithm,RAA)的装备SoS总体任务成功性仿真评估算法,启动仿真模型运行,实现对装备SoS总体任务成功性的有效评估,并通过案例分析,验证了模型的适用性。