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951.
在对弹道修正弹系统可靠性进行定义的基础上,建立该系统的可靠性框图和可靠性数学模型,提出了弹道修正弹系统可靠度的计算方法,同时介绍了可靠度分配在弹道修正弹系统中的应用问题。研究结论为弹道修正弹系统设计提供参考,也为弹道修正弹系统效能评估提供依据。 相似文献
952.
Considering the static stability and the change of the displacement volume, including the influences of higher order nonlinear terms and the instantaneous wave surface, the nonlinear coupled heave-pitch motion was established in stochastic waves. The responses of heave-pitch coupling motion for the Truss Spar platform were investigated. It was found that, when the characteristic frequency of a stochastic wave is close to the natural heave frequency, the large amplitude pitch motion is induced under the parametric-forced excitation, which is called the Mathieu instability. It was observed that the heave mode energy is transferred to pitch mode when the heave motion amplitude exceeds a certain extent. In addition, the probability of internal resonant heave-pitch motion is greatly reduced while the characteristic wave frequency is away from the natural heave frequency. 相似文献
953.
The effects of stochastic characteristics of materials on the reliability of ship hulls made of composite materials under longitudinal moment were extensively studied using reliability and sensitivity calculations of a composite ship hull which was sagging.The reliability indices and failure probabilities of the ship in three kinds of failure modes (buckling,material failure,and ultimate collapse) were calculated by the surface response method and JC method.The importance factors of random variables in stochastic models,such as the model errors in predicting the ultimate longitudinal strength of ship and the longitudinal bending moment that the ship withstands,as well as the stochastic characteristics of materials in the models used,were calculated.Then,the effects of these random variables,including the stochastic characteristics of materials on the reliability index and the failure probability of ships which were sagging,were discussed with their importance factors.The results show that the effects of stochastic characteristics of materials on the reliability of ship hulls made of composite materials should be considered during the reliability assessment of composite ships.Finally,some conclusions and recommendations were given for high-speed ship design and safety assessment. 相似文献
954.
结合国内高速公路和从业现状,从优化环境、加快培养和提升建设三方面努力探索一条高速公路行业监管人才培养的新路,可以起到促进高速公路行业长期科学、和谐发展的作用。 相似文献
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随着城市交通建设的发展,城市隧道作为城市交通的重要手段,逐步成为城市交通建设重要组成部分。城市隧道的装饰工程是城市交通建设中的重要组成,体现城市发展的面貌,表达出城市建设发展的地域化、现代化、系统化。城市隧道的建筑装饰可以展现一个城市的发展历程,体现城市交通发展的方向。该文结合实际工程,阐述了城市隧道工程中有关洞口部位、隧道内部及通风管道的建筑装饰,可供同行参考。 相似文献
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