The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are d...The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are designed under the uncertain environment or neutrosophic statistical interval system,when all observations are undermined,imprecise or fuzzy.These are termed neutrosophic double and triple exponentially weighted moving average(NDEWMA and NTEWMA)control charts.For the proficiency of the proposed chart,Monte Carlo simulations are used to calculate the run-length characteristics(such as average run length(ARL),standard deviation of the run length(SDRL),percentiles(P_(25),P_(50),P_(75)))of the proposed charts.The structures of the proposed control charts are more effective in detecting small shifts while these are comparable with the other existing charts in detecting moderate and large shifts.The simulation study and real-life implementations of the proposed charts show that the proposed NDEWMA and NTEWMA charts perform better in monitoring the process of road traffic crashes and electric engineering data as compared to the existing control charts.Therefore,the proposed charts will be helpful in minimizing the road accident and minimizing the defective products.Furthermore,the proposed charts are more acceptable and actual to apply in uncertain environment.展开更多
针对应用多工况过程k近邻方法(k-nearest neighbor,k NN)进行故障检测时,微小故障样本较难被检测的问题,提出一种基于改进指数加权移动平均算法的k近邻(k NN based on exponentially weighted moving average,EWMA-k NN)故障检测方法....针对应用多工况过程k近邻方法(k-nearest neighbor,k NN)进行故障检测时,微小故障样本较难被检测的问题,提出一种基于改进指数加权移动平均算法的k近邻(k NN based on exponentially weighted moving average,EWMA-k NN)故障检测方法.考虑到过程为多工况过程,所以利用k NN方法建立故障检测模型,计算距离统计量并确定相应的控制限.在过程监视中,使用改进EWMA算法更新控制限,赋予统计量随时间递增的权重,利用加权统计量和离线控制限确定当前微小故障样本相应的控制限.数值案例和半导体生产过程的仿真实验结果表明了该方法的有效性.展开更多
为提高风电机组运行效率,降低风电场运营成本,对风电机组运行状态监测显得尤为重要,提出一种基于数据采集与监控(supervisory control and data acquisition,简称SCADA)系统和萤火虫改进麻雀搜索算法优化深度置信网络(firefly improved ...为提高风电机组运行效率,降低风电场运营成本,对风电机组运行状态监测显得尤为重要,提出一种基于数据采集与监控(supervisory control and data acquisition,简称SCADA)系统和萤火虫改进麻雀搜索算法优化深度置信网络(firefly improved sparrow search algorithm optimized deep belief network,简称FISSA-DBN)的风电机组状态监测新方法。首先,对SCADA数据进行预处理分析,并利用专家系统和皮尔逊相关系数分析,相关分析选取输入参数和输出参数;其次,利用预处理数据集建立基于FISSA-DBN的风电机组运行状态监测新模型,根据模型预测值和实际输出值之间的重构值误差,以及指数加权移动平均阈值(exponentially weighted moving average,简称EWMA)判断是否有异常;最后,以华东某风电场实际数据为例进行实例验证。结果表明,所提出方法的预警时间比实际记录时间最早可提前4 d多。同时,将所提出方法与其他方法进行对比,结果表明该方法预警时间提前,模型预测误差更小。展开更多
With the advancement in the science and technology,cloud computing has become a recent trend in environment with immense requirement of infrastructure and resources.Load balancing of cloud computing environments is an...With the advancement in the science and technology,cloud computing has become a recent trend in environment with immense requirement of infrastructure and resources.Load balancing of cloud computing environments is an important matter of concern.The migration of the overloaded virtual machines(VMs)to the underloaded VM with optimized resource utilization is the effective way of the load balancing.In this paper,a new VM migration algorithm for the load balancing in the cloud is proposed.The migration algorithm proposed(EGSA-VMM)is based on exponential gravitational search algorithm which is the integration of gravitational search algorithm and exponential weighted moving average theory.In our approach,the migration is done based on the migration cost and QoS.The experimentation of proposed EGSA-based VM migration algorithm is compared with ACO and GSA.The simulation of experiments shows that the proposed EGSA-VMM algorithm achieves load balancing and reasonable resource utilization,which outperforms existing migration strategies in terms of number of VM migrations and number of SLA violations.展开更多
主元分析(principal component analysis,PCA)是一种有效的数据分析方法,在故障诊断与状态监测方面已得到广泛应用.多元指数加权移动平均–主元分析(multivariate exponentially weighted moving average principal component analysis,...主元分析(principal component analysis,PCA)是一种有效的数据分析方法,在故障诊断与状态监测方面已得到广泛应用.多元指数加权移动平均–主元分析(multivariate exponentially weighted moving average principal component analysis,MEWMA–PCA)方法用于解决PCA不能有效检出微小故障的问题.本文深入研究了MEWMA–PCA中EWMA影响主元分析进行故障检测的机制,导出了MEWMA–PCA可检出微小故障的原因.本文确定了MEWMA–PCA中遗忘因子λ、单传感器故障幅值和迟延时间三者的关系,并进行了数值仿真和火电厂磨煤机组运行状态的仿真实验.实验结果验证了MEWMA–PCA中EWMA提高PCA的监测性能的机制,并给出了根据系统实际要求来选取合适的遗忘因子值,从而在规定的时间内检出微小故障的实例.展开更多
基金This work was funded by the Deanship of Scientific Research(DSR),King Abdulaziz University,JeddahThe authors,therefore,gratefully acknowledge the DSR technical and financial support.
文摘The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are designed under the uncertain environment or neutrosophic statistical interval system,when all observations are undermined,imprecise or fuzzy.These are termed neutrosophic double and triple exponentially weighted moving average(NDEWMA and NTEWMA)control charts.For the proficiency of the proposed chart,Monte Carlo simulations are used to calculate the run-length characteristics(such as average run length(ARL),standard deviation of the run length(SDRL),percentiles(P_(25),P_(50),P_(75)))of the proposed charts.The structures of the proposed control charts are more effective in detecting small shifts while these are comparable with the other existing charts in detecting moderate and large shifts.The simulation study and real-life implementations of the proposed charts show that the proposed NDEWMA and NTEWMA charts perform better in monitoring the process of road traffic crashes and electric engineering data as compared to the existing control charts.Therefore,the proposed charts will be helpful in minimizing the road accident and minimizing the defective products.Furthermore,the proposed charts are more acceptable and actual to apply in uncertain environment.
文摘针对应用多工况过程k近邻方法(k-nearest neighbor,k NN)进行故障检测时,微小故障样本较难被检测的问题,提出一种基于改进指数加权移动平均算法的k近邻(k NN based on exponentially weighted moving average,EWMA-k NN)故障检测方法.考虑到过程为多工况过程,所以利用k NN方法建立故障检测模型,计算距离统计量并确定相应的控制限.在过程监视中,使用改进EWMA算法更新控制限,赋予统计量随时间递增的权重,利用加权统计量和离线控制限确定当前微小故障样本相应的控制限.数值案例和半导体生产过程的仿真实验结果表明了该方法的有效性.
文摘为提高风电机组运行效率,降低风电场运营成本,对风电机组运行状态监测显得尤为重要,提出一种基于数据采集与监控(supervisory control and data acquisition,简称SCADA)系统和萤火虫改进麻雀搜索算法优化深度置信网络(firefly improved sparrow search algorithm optimized deep belief network,简称FISSA-DBN)的风电机组状态监测新方法。首先,对SCADA数据进行预处理分析,并利用专家系统和皮尔逊相关系数分析,相关分析选取输入参数和输出参数;其次,利用预处理数据集建立基于FISSA-DBN的风电机组运行状态监测新模型,根据模型预测值和实际输出值之间的重构值误差,以及指数加权移动平均阈值(exponentially weighted moving average,简称EWMA)判断是否有异常;最后,以华东某风电场实际数据为例进行实例验证。结果表明,所提出方法的预警时间比实际记录时间最早可提前4 d多。同时,将所提出方法与其他方法进行对比,结果表明该方法预警时间提前,模型预测误差更小。
文摘With the advancement in the science and technology,cloud computing has become a recent trend in environment with immense requirement of infrastructure and resources.Load balancing of cloud computing environments is an important matter of concern.The migration of the overloaded virtual machines(VMs)to the underloaded VM with optimized resource utilization is the effective way of the load balancing.In this paper,a new VM migration algorithm for the load balancing in the cloud is proposed.The migration algorithm proposed(EGSA-VMM)is based on exponential gravitational search algorithm which is the integration of gravitational search algorithm and exponential weighted moving average theory.In our approach,the migration is done based on the migration cost and QoS.The experimentation of proposed EGSA-based VM migration algorithm is compared with ACO and GSA.The simulation of experiments shows that the proposed EGSA-VMM algorithm achieves load balancing and reasonable resource utilization,which outperforms existing migration strategies in terms of number of VM migrations and number of SLA violations.
文摘主元分析(principal component analysis,PCA)是一种有效的数据分析方法,在故障诊断与状态监测方面已得到广泛应用.多元指数加权移动平均–主元分析(multivariate exponentially weighted moving average principal component analysis,MEWMA–PCA)方法用于解决PCA不能有效检出微小故障的问题.本文深入研究了MEWMA–PCA中EWMA影响主元分析进行故障检测的机制,导出了MEWMA–PCA可检出微小故障的原因.本文确定了MEWMA–PCA中遗忘因子λ、单传感器故障幅值和迟延时间三者的关系,并进行了数值仿真和火电厂磨煤机组运行状态的仿真实验.实验结果验证了MEWMA–PCA中EWMA提高PCA的监测性能的机制,并给出了根据系统实际要求来选取合适的遗忘因子值,从而在规定的时间内检出微小故障的实例.
