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武隆隧道为渝怀铁路第二长大隧道,岩溶发育是本隧道的最主要特征之一.尤涫?#和3#岩溶暗河,为本隧道最复杂、最困难的地质条件,多次出现大型~特大型岩溶涌水,给隧道施工造成无法抗拒的自然灾害和经济损失.作者详细介绍了2#和3#岩溶暗河的探测技术,并根据探测结果提出岩溶暗河处理措施和建议. 相似文献
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遗传算法在区段站到发线的应用研究 总被引:4,自引:2,他引:4
青学江 《西南交通大学学报》1998,33(4):387-393
为解决车站到发线的合理运用问题,采用遗传算建立了到发线运用的染色体结构和适应度函数,对这种复杂的非线性组合优化问题进行了仿真。 相似文献
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介绍武汉阳逻长江公路大桥南锚碇工程采用设计-施工总承包模式的经验,对相关的招标和项目管理工作进行总结.针对我国的实际情况,分析该模式在工程建设中的适用范围. 相似文献
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With the development of vehicle gearbox to high-power-density and high-speed, how to predict and optimize the dynamic characteristics of vehicle gearbox becomes increasingly prominent. Aiming at the vehicle gearbox, this paper comprehensively and deeply studies the dynamic characteristics under the multi-boundary conditions. The generation mechanism of the multi-source excitations triggering the gearbox vibration is analyzed firstly. The vibration transfer path of the gearbox is explored. Secondly, the engine excitation, the gear meshing excitation and the bearing support load are numerically calculated. According to the finite element method, a fluid-solid coupling finite element model of the gearbox body is established to predict the gearbox dynamic responses based on the Galerkin method and the Hamiltonian variational principle. Finally, the effects of the excitation condition, oil height and reinforcement forms on the vibration responses of the gearbox body are thoroughly studied by simulation. The analysis indicates that it not only helps to modify and improve the method of forecasting the gearbox dynamic response, and also provides the theoretical and technical guidance for the gearbox design and optimization. 相似文献
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Along with higher and higher integration of intellectual properties (IPs) on a single chip, traditional bus-based system-on-chips (SoC) meets several design difficulties (such as low scalability, high power consumption, packet latency and clock tree problem). As a promising solution, network-on-chips (NoC) has been proposed and widely studied. In this work, a novel algorithm for NoC topology synthesis, which is decomposing and cluster refinement (DCR) algorithm, has been proposed to minimize the total power consumption of application-specific NoC. This algorithm is composed of two stages: decomposing with cluster generation, and cluster refinement. For partitioning and cluster generation, an initial low-power solution for NoC topology is generated. For cluster refinement, the clustering is optimized by performing floorplan to further reduce power consumption. Meanwhile, a good tradeoff between power consumption and CPU time can be achieved. Experimental results show that the proposed method outperforms the existing work. 相似文献