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美国海军的“伯克”级驱逐舰拥有强大的对地攻击能力,卓越的防空和对舰作战能力。本文剖析了“伯克”级驱逐舰的反导作战思想,对其探测跟踪能力,作战反应能力以及打击平台,区域防空,点防御和电子战等方面的能力进行详细的讨论,从而找出其反导作战存在的薄弱点,为反舰导弹突防研究提供参考。 相似文献
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富水破碎小净距隧道施工技术 总被引:1,自引:0,他引:1
通过横山隧道进口段富水破碎小净距隧道的成功实施,系统地介绍了富水破碎小净距隧道施工的综合技术,包括开挖方案优化、支护施工技术(重点是中夹岩柱加固措施及支护体系加强措施)及富水处理措施(井点降水方法),体现了施工方案的安全性和经济性。 相似文献
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To meet the increasing applications of the deepwater steel lazy-wave riser (SLWR), the riser abandonment and recovery (A&R) is a great challenge for SLWR installation and its mechanical analysis is necessary and significant. This paper is focused on the abandonment and recovery process which is of great importance to the installation feasibility and analysis. A comprehensive mechanical model based on the nonlinear large deformation beam theory for simulating the deepwater SLWR is proposed. And a simple and suitable model for analyzing the A&R cable is developed. The presented model with detailed boundary conditions is able to deal with three different A&R methods. Numerical analysis is conducted by the finite difference method to investigate the riser configurations and somev important mechanical parameters of the pipeline and cable which exert influences on the riser's performance and the A&R cable's requirement. Parametric comparison study is conducted to analyze the advantage of different method. The proposed model can help on development of deepwater SLWR A&R design and analysis. 相似文献
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在隧洞围岩稳定性分析中,运用可靠度理论比传统的安全系数法更符合实际。以圆形隧洞围岩的弹塑性分析的解析解为基础,建立圆形隧洞围岩稳定性分析的可靠度分析模型。考虑到功能函数的高度非线性,采用Fortran语言编制可靠指标的计算程序,并结合实例对可靠指标的影响因素进行分析。 相似文献
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A schedule consisting of an appropriate arrival time at each time control point can ensure reliable transport services. This paper develops a novel time control point strategy coupled with transfer coordination for solving a multi‐objective schedule design problem to improve schedule adherence and reduce intermodal transfer disutility. The problem is formulated using a robust mixed‐integer nonlinear programming model. The mixed‐integer nonlinear programming model is equivalently transformed into a robust mixed‐integer linear programming model, which is then approximated by a deterministic mixed‐integer linear programming model through Monte Carlo simulation. Thus, the optimal scheduled arrival time at each time control point can be precisely obtained using cplex . Numerical experiments based on three bus lines and the mass rapid transit system in Singapore are presented, and the results show that the schedule determined using the developed model is able to provide not only reliable bus service but also a smooth transfer experience for passengers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Our daily driving experience and empirical observations suggest that traffic patterns in a road network are relatively stationary during peak periods. In numerous transportation network studies, there has been an implicit conjecture that stationary states exist in a network when origin demands, route choice proportions, and destination supplies are constant. In this study, we first rigorously formulate the conjecture within the framework of a network kinematic wave theory with an invariant junction model. After defining stationary states, we derive a system of algebraic equations in 3-tuples of stationary link flow-rates, demands, and supplies. We then introduce a new definition of junction critical demand levels based on effective demands and supplies. With a map in critical demand levels, we show that its fixed points and, therefore, stationary states exist with the help of Brouwer’s fixed point theorem. For two simple road networks, we show that the map is well-defined and can be used to solve stationary states with a brute-force method. Finally we summarize the study and present some future extensions and applications. 相似文献