To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise mode...To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise modeling strategy,cell array operation principle,and Copula theory.Under this framework,we propose a DSM-based Enhanced Kriging(DSMEK)algorithm to synchronously derive the modeling of multi-objective,and explore an adaptive Copula function approach to analyze the correlation among multiple objectives and to assess the synthetical reliability level.In the proposed DSMEK and adaptive Copula methods,the Kriging model is treated as the basis function of DSMEK model,the Multi-Objective Snake Optimizer(MOSO)algorithm is used to search the optimal values of hyperparameters of basis functions,the cell array operation principle is adopted to establish a whole model of multiple objectives,the goodness of fit is utilized to determine the forms of Copula functions,and the determined Copula functions are employed to perform the reliability analyses of the correlation of multi-analytical objectives.Furthermore,three examples,including multi-objective complex function approximation,aeroengine turbine bladeddisc multi-failure mode reliability analyses and aircraft landing gear system brake temperature reliability analyses,are performed to verify the effectiveness of the proposed methods,from the viewpoints of mathematics and engineering.The results show that the DSMEK and adaptive Copula approaches hold obvious advantages in terms of modeling features and simulation performance.The efforts of this work provide a useful way for the modeling of multi-analytical objectives and synthetical reliability analyses of complex structure/system with multi-output responses.展开更多
Communication networks rely on time synchronization information generated by base station equipment(either the Global Navigation Satellite System receiver or rubidium atomic clock) to enable wireless networking and co...Communication networks rely on time synchronization information generated by base station equipment(either the Global Navigation Satellite System receiver or rubidium atomic clock) to enable wireless networking and communications. Meanwhile, the time synchronization among base stations depends on the Network Time Protocol. With the development of mobile communication systems, the corresponding time synchronization accuracy has increased as well. In this case, the use of sparsely distributed-high-precision synchronization points to synchronize time for an entire network with high precision is a key problem and is the foundation of the enhanced network communication. The current receiver equipment for China's digital synchronous network typically includes dedicated multi-channel GPS receivers for communication; however, with the development of GPS by the USA, network security has been destabilized and reliability is low. Nonetheless, network time synchronization based on Beidou satellite navigation system timing devices is an inevitable development trend for China's digital communications network with the establishment of the independently developed BDS, especially the implementation and improvement of the Beidou foundation enhancement system.展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.52405293,52375237)China Postdoctoral Science Foundation(No.2024M754219)Shaanxi Province Postdoctoral Research Project Funding,China。
文摘To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise modeling strategy,cell array operation principle,and Copula theory.Under this framework,we propose a DSM-based Enhanced Kriging(DSMEK)algorithm to synchronously derive the modeling of multi-objective,and explore an adaptive Copula function approach to analyze the correlation among multiple objectives and to assess the synthetical reliability level.In the proposed DSMEK and adaptive Copula methods,the Kriging model is treated as the basis function of DSMEK model,the Multi-Objective Snake Optimizer(MOSO)algorithm is used to search the optimal values of hyperparameters of basis functions,the cell array operation principle is adopted to establish a whole model of multiple objectives,the goodness of fit is utilized to determine the forms of Copula functions,and the determined Copula functions are employed to perform the reliability analyses of the correlation of multi-analytical objectives.Furthermore,three examples,including multi-objective complex function approximation,aeroengine turbine bladeddisc multi-failure mode reliability analyses and aircraft landing gear system brake temperature reliability analyses,are performed to verify the effectiveness of the proposed methods,from the viewpoints of mathematics and engineering.The results show that the DSMEK and adaptive Copula approaches hold obvious advantages in terms of modeling features and simulation performance.The efforts of this work provide a useful way for the modeling of multi-analytical objectives and synthetical reliability analyses of complex structure/system with multi-output responses.
文摘Communication networks rely on time synchronization information generated by base station equipment(either the Global Navigation Satellite System receiver or rubidium atomic clock) to enable wireless networking and communications. Meanwhile, the time synchronization among base stations depends on the Network Time Protocol. With the development of mobile communication systems, the corresponding time synchronization accuracy has increased as well. In this case, the use of sparsely distributed-high-precision synchronization points to synchronize time for an entire network with high precision is a key problem and is the foundation of the enhanced network communication. The current receiver equipment for China's digital synchronous network typically includes dedicated multi-channel GPS receivers for communication; however, with the development of GPS by the USA, network security has been destabilized and reliability is low. Nonetheless, network time synchronization based on Beidou satellite navigation system timing devices is an inevitable development trend for China's digital communications network with the establishment of the independently developed BDS, especially the implementation and improvement of the Beidou foundation enhancement system.
