In view of the shortcomings of traditional teaching in the Mechanical Design Fundamentals course,the teaching resources are integrated,the teaching content,teaching methods,and assessment methods are reformed,scientif...In view of the shortcomings of traditional teaching in the Mechanical Design Fundamentals course,the teaching resources are integrated,the teaching content,teaching methods,and assessment methods are reformed,scientific research results are introduced into course teaching,and the task-driven teaching practice is applied.These measures have improved classroom activity,stimulated independent learning,and laid the foundation for the cultivation of students’engineering literacy and innovative ability.展开更多
From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived f...From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived from the framework is then used to achieve complete synchronization of networked identical or non-identical multibody systems formulated with Lagrangian dynamics. A distinctive feature of the developed control strategy is the introduction of network structures into the control requirement. The control law consists of two components, the first describing the architecture of the network and the second denoting an active feedback control strategy. A corresponding stability analysis is performed by the algebraic graph theory. A representative network composed of ten identical or non-identical gyroscopes is used as an illustrative example. Numerical simulation of the systems with three kinds of network structures, including global coupling, nearest-neighbour, and small-world networks, is given to demonstrate effectiveness of the proposed control methodology.展开更多
The study of irradiation hardening and embrittlement is critically important for the development of next-generation structural materials tolerant to neutron irradiation,and could dramatically affect the approach to th...The study of irradiation hardening and embrittlement is critically important for the development of next-generation structural materials tolerant to neutron irradiation,and could dramatically affect the approach to the design of components for advanced nuclear reactors.In addition,a growing interest is observed in the field of research and development of irradiation-resistant materials.This review aims to provide an overview of the theoretical development related to irradiation hardening and embrittlement at moderate irradiation conditions achieved in recent years,which can help extend our fundamental knowledge on nuclear structural materials.After a general introduction to the irradiation effects on metallic materials,recent research progress covering theoretical modelling is summarized for different types of structural materials.The fundamental mechanisms are elucidated within a wide range of temporal and spatial scales.This review closes with the current understanding of irradiation hardening and embrittlement,and puts some perspectives deserving further study.展开更多
基金The Education and Teaching Research Project of National University of Defense Technology(Project Number:U2020103)。
文摘In view of the shortcomings of traditional teaching in the Mechanical Design Fundamentals course,the teaching resources are integrated,the teaching content,teaching methods,and assessment methods are reformed,scientific research results are introduced into course teaching,and the task-driven teaching practice is applied.These measures have improved classroom activity,stimulated independent learning,and laid the foundation for the cultivation of students’engineering literacy and innovative ability.
基金Project supported by the National Natural Science Foundation of China(Nos.10972129 and 11272191)the Specialized Research Foundation for the Doctoral Program of Higher Education(No.200802800015)+1 种基金the Science and Technology Project of High Schools of Shandong Province(No.J15LJ07)the Shandong Provincial Natural Science Foundation(No.ZR2015FL026)
文摘From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived from the framework is then used to achieve complete synchronization of networked identical or non-identical multibody systems formulated with Lagrangian dynamics. A distinctive feature of the developed control strategy is the introduction of network structures into the control requirement. The control law consists of two components, the first describing the architecture of the network and the second denoting an active feedback control strategy. A corresponding stability analysis is performed by the algebraic graph theory. A representative network composed of ten identical or non-identical gyroscopes is used as an illustrative example. Numerical simulation of the systems with three kinds of network structures, including global coupling, nearest-neighbour, and small-world networks, is given to demonstrate effectiveness of the proposed control methodology.
基金the National Natural Science foundation of China(NSFC)(Grants 11632001,11521202,11802344)Natural Science Foundation of Hunan Province,China(Grant 2019JJ50809).
文摘The study of irradiation hardening and embrittlement is critically important for the development of next-generation structural materials tolerant to neutron irradiation,and could dramatically affect the approach to the design of components for advanced nuclear reactors.In addition,a growing interest is observed in the field of research and development of irradiation-resistant materials.This review aims to provide an overview of the theoretical development related to irradiation hardening and embrittlement at moderate irradiation conditions achieved in recent years,which can help extend our fundamental knowledge on nuclear structural materials.After a general introduction to the irradiation effects on metallic materials,recent research progress covering theoretical modelling is summarized for different types of structural materials.The fundamental mechanisms are elucidated within a wide range of temporal and spatial scales.This review closes with the current understanding of irradiation hardening and embrittlement,and puts some perspectives deserving further study.