Modernization of armies is a constant process and is driven by intuitive fact that those who do not modernize will become extinct. In last five decades, the development of modern armies has taken place around Colonel ...Modernization of armies is a constant process and is driven by intuitive fact that those who do not modernize will become extinct. In last five decades, the development of modern armies has taken place around Colonel John Boyd’s theory of OODA loop that deals with information superiority. Building a robust, mobile and capable network that could provide for novel appliances and information superiority is the main challenge which modernizers are facing. Network, suitable for future combat operations, and able to transport a vast amount of information on a battlefield, is expensive to build. Every mistake in design and the need to correct those mistakes could halt development in an army for years. Therefore, system dependability analysis during system design phase is needed. In this report, the concept of a future Battle Network System is described. The Report evaluates operational environment of BNS and possible failure reasons of the service, and illustrates the change in BNS Quality of Service due to probable transport layer errors. This paper describes the method of testing the concept of proposed network systems on the drawing board, and emphasizes design points for a new system. Nevertheless, the proposed method is by no means conclusive. Rather, it describes an engineering approach to define the main problems while creating MANET-based networking systems.展开更多
Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the ...Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the back-propagation artificial neural network(BP-ANN), which is trained by finite element simulation results. Moreover, the finite element method(FEM) for wing blast damage simulation has been validated by ground explosion tests and further used for damage mode determination and damage characteristics analysis. The analysis results indicate that the wing is more likely to be damaged when the root is struck from vertical directions than others for a small charge. With the increase of TNT equivalent charge, the main damage mode of the wing gradually changes from the local skin tearing to overall structural deformation and the overpressure threshold of wing damage decreases rapidly. Compared to the FEM-based damage assessment, the BP-ANN-based method can predict the wing damage under a random blast wave with an average relative error of 4.78%. The proposed method and conclusions can be used as a reference for damage assessment under blast wave and low-vulnerability design of aircraft structures.展开更多
文摘Modernization of armies is a constant process and is driven by intuitive fact that those who do not modernize will become extinct. In last five decades, the development of modern armies has taken place around Colonel John Boyd’s theory of OODA loop that deals with information superiority. Building a robust, mobile and capable network that could provide for novel appliances and information superiority is the main challenge which modernizers are facing. Network, suitable for future combat operations, and able to transport a vast amount of information on a battlefield, is expensive to build. Every mistake in design and the need to correct those mistakes could halt development in an army for years. Therefore, system dependability analysis during system design phase is needed. In this report, the concept of a future Battle Network System is described. The Report evaluates operational environment of BNS and possible failure reasons of the service, and illustrates the change in BNS Quality of Service due to probable transport layer errors. This paper describes the method of testing the concept of proposed network systems on the drawing board, and emphasizes design points for a new system. Nevertheless, the proposed method is by no means conclusive. Rather, it describes an engineering approach to define the main problems while creating MANET-based networking systems.
基金supported by the Natural Science Foundation of Shaanxi Province (Grant No. 2020JQ-122)the Fund support of Science and Technology on Transient Impact Laboratory。
文摘Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the back-propagation artificial neural network(BP-ANN), which is trained by finite element simulation results. Moreover, the finite element method(FEM) for wing blast damage simulation has been validated by ground explosion tests and further used for damage mode determination and damage characteristics analysis. The analysis results indicate that the wing is more likely to be damaged when the root is struck from vertical directions than others for a small charge. With the increase of TNT equivalent charge, the main damage mode of the wing gradually changes from the local skin tearing to overall structural deformation and the overpressure threshold of wing damage decreases rapidly. Compared to the FEM-based damage assessment, the BP-ANN-based method can predict the wing damage under a random blast wave with an average relative error of 4.78%. The proposed method and conclusions can be used as a reference for damage assessment under blast wave and low-vulnerability design of aircraft structures.