Satisfactory results cannot be obtained when three-dimensional (3D) targets with complex maneuvering characteristics are tracked by the commonly used two-dimensional coordinated turn (2DCT) model. To address the probl...Satisfactory results cannot be obtained when three-dimensional (3D) targets with complex maneuvering characteristics are tracked by the commonly used two-dimensional coordinated turn (2DCT) model. To address the problem of 3D target tracking with strong maneuverability, on the basis of the modified three-dimensional variable turn (3DVT) model, an adaptive tracking algorithm is proposed by combining with the cubature Kalman filter (CKF) in this paper. Through ideology of real-time identification, the parameters of the model are changed to adjust the state transition matrix and the state noise covariance matrix. Therefore, states of the target are matched in real-time to achieve the purpose of adaptive tracking. Finally, four simulations are analyzed in different settings by the Monte Carlo method. All results show that the proposed algorithm can update parameters of the model and identify motion characteristics in real-time when targets tracking also has a better tracking accuracy.展开更多
陶瓷在长时高温和高应力下工作时会发生蠕变,蠕变损伤累积将最终导致失效发生。蠕变损伤的演化与陶瓷的微结构有十分密切的关系,建立陶瓷材料的微观有限元模型有助于更深入地了解这一关系。以氮化硅陶瓷为研究对象,提出一种基于动力学...陶瓷在长时高温和高应力下工作时会发生蠕变,蠕变损伤累积将最终导致失效发生。蠕变损伤的演化与陶瓷的微结构有十分密切的关系,建立陶瓷材料的微观有限元模型有助于更深入地了解这一关系。以氮化硅陶瓷为研究对象,提出一种基于动力学的三维晶体沉积数值模型,结合Monte Carlo Potts结晶生长模型对氮化硅陶瓷的烧结过程进行模拟,力求还原氮化硅陶瓷的动态生长过程以及结晶后晶体大小、形状、取向分布以及空洞的大小、形状、分布等微观结构特征。基于该模拟生成的几何边界描述自动生成Python脚本,在有限元软件中完成建模。利用该有限元模型对氮化硅陶瓷的统计弹性常数进行验证,计算结果与试验数据对比,相对误差约为4.5%,吻合良好。展开更多
基金supported by the National Natural Science Foundation of China(51467013)
文摘Satisfactory results cannot be obtained when three-dimensional (3D) targets with complex maneuvering characteristics are tracked by the commonly used two-dimensional coordinated turn (2DCT) model. To address the problem of 3D target tracking with strong maneuverability, on the basis of the modified three-dimensional variable turn (3DVT) model, an adaptive tracking algorithm is proposed by combining with the cubature Kalman filter (CKF) in this paper. Through ideology of real-time identification, the parameters of the model are changed to adjust the state transition matrix and the state noise covariance matrix. Therefore, states of the target are matched in real-time to achieve the purpose of adaptive tracking. Finally, four simulations are analyzed in different settings by the Monte Carlo method. All results show that the proposed algorithm can update parameters of the model and identify motion characteristics in real-time when targets tracking also has a better tracking accuracy.
文摘陶瓷在长时高温和高应力下工作时会发生蠕变,蠕变损伤累积将最终导致失效发生。蠕变损伤的演化与陶瓷的微结构有十分密切的关系,建立陶瓷材料的微观有限元模型有助于更深入地了解这一关系。以氮化硅陶瓷为研究对象,提出一种基于动力学的三维晶体沉积数值模型,结合Monte Carlo Potts结晶生长模型对氮化硅陶瓷的烧结过程进行模拟,力求还原氮化硅陶瓷的动态生长过程以及结晶后晶体大小、形状、取向分布以及空洞的大小、形状、分布等微观结构特征。基于该模拟生成的几何边界描述自动生成Python脚本,在有限元软件中完成建模。利用该有限元模型对氮化硅陶瓷的统计弹性常数进行验证,计算结果与试验数据对比,相对误差约为4.5%,吻合良好。
