传统的KPCA(Kernel Principal Component Analysis)过程监测方法一般根据经验选取需要的核函数及一定宽度的参数,这样做是非常盲目的。同时单一KPCA模型不能对所有故障都有好的监测效果。为了解决此问题,提出基于集成KPCA的非线性工业...传统的KPCA(Kernel Principal Component Analysis)过程监测方法一般根据经验选取需要的核函数及一定宽度的参数,这样做是非常盲目的。同时单一KPCA模型不能对所有故障都有好的监测效果。为了解决此问题,提出基于集成KPCA的非线性工业过程状态监测方法。通过选取一系列的核函数及其参数构建不同的KPCA模型得到子模型,用贝叶斯方法将众多子模型的监测统计量转化为故障概率,分两步进行融合,得到最终监测结果。实验结果表明,该方法显著地提高了监测性能,同时减小核函数及参数选取对故障监测的影响。展开更多
The implementation of Intelligent Transport System (ITS) technology is expected to significantly improve road safety and traffic efficiency. One of the key components of ITS is precise vehicle positioning. Positioning...The implementation of Intelligent Transport System (ITS) technology is expected to significantly improve road safety and traffic efficiency. One of the key components of ITS is precise vehicle positioning. Positioning with decimetre to sub-metre accuracy is a fundamental capability for self-driving, and other automated applications. Global Navigation Satellite System (GNSS) Precise Point Positioning (PPP) is an attractive positioning approach for ITS due to its relatively low-cost and flexibility. However, GNSS PPP is vulnerable to several effects, especially those caused by the challenging urban environments, where the ITS technology is most likely needed. To meet the high integrity requirements of ITS applications, it is necessary to carefully analyse potential faults and failures of PPP and to study relevant integrity monitoring methods. In this paper an overview of vulnerabilities of GNSS PPP is presented to identify the faults that need to be monitored when developing PPP integrity monitoring methods. These vulnerabilities are categorised into different groups according to their impact and error sources to assist integrity fault analysis, which is demonstrated with Failure Modes and Effects Analysis (FMEA) and Fault Tree Analysis (FTA) methods. The main vulnerabilities are discussed in detail, along with their causes, characteristics, impact on users, and related mitigation methods. In addition, research on integrity monitoring methods used for accounting for the threats and faults in PPP for ITS applications is briefly reviewed. Both system-level (network-end) and user-level (user-end) integrity monitoring approaches for PPP are briefly discussed, focusing on their development and the challenges in urban scenarios. Some open issues, on which further efforts should focus, are also identified.展开更多
文摘传统的KPCA(Kernel Principal Component Analysis)过程监测方法一般根据经验选取需要的核函数及一定宽度的参数,这样做是非常盲目的。同时单一KPCA模型不能对所有故障都有好的监测效果。为了解决此问题,提出基于集成KPCA的非线性工业过程状态监测方法。通过选取一系列的核函数及其参数构建不同的KPCA模型得到子模型,用贝叶斯方法将众多子模型的监测统计量转化为故障概率,分两步进行融合,得到最终监测结果。实验结果表明,该方法显著地提高了监测性能,同时减小核函数及参数选取对故障监测的影响。
基金the Australian Research Council(ARC)Project No.DP170103341.
文摘The implementation of Intelligent Transport System (ITS) technology is expected to significantly improve road safety and traffic efficiency. One of the key components of ITS is precise vehicle positioning. Positioning with decimetre to sub-metre accuracy is a fundamental capability for self-driving, and other automated applications. Global Navigation Satellite System (GNSS) Precise Point Positioning (PPP) is an attractive positioning approach for ITS due to its relatively low-cost and flexibility. However, GNSS PPP is vulnerable to several effects, especially those caused by the challenging urban environments, where the ITS technology is most likely needed. To meet the high integrity requirements of ITS applications, it is necessary to carefully analyse potential faults and failures of PPP and to study relevant integrity monitoring methods. In this paper an overview of vulnerabilities of GNSS PPP is presented to identify the faults that need to be monitored when developing PPP integrity monitoring methods. These vulnerabilities are categorised into different groups according to their impact and error sources to assist integrity fault analysis, which is demonstrated with Failure Modes and Effects Analysis (FMEA) and Fault Tree Analysis (FTA) methods. The main vulnerabilities are discussed in detail, along with their causes, characteristics, impact on users, and related mitigation methods. In addition, research on integrity monitoring methods used for accounting for the threats and faults in PPP for ITS applications is briefly reviewed. Both system-level (network-end) and user-level (user-end) integrity monitoring approaches for PPP are briefly discussed, focusing on their development and the challenges in urban scenarios. Some open issues, on which further efforts should focus, are also identified.
