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中小型站房网架屋盖支座弹性刚度取值研究 总被引:1,自引:0,他引:1
《铁道标准设计通讯》2017,(11):116-120
结合沪昆高铁平坝南站站房结构这一具体工程实例,进行中小型站房网架屋盖支座弹性刚度取值的研究。通过下部框架结构位移函数值,拟合出下部X轴支承结构Y方向的支座水平刚度公式。根据公式计算得到下部支承结构的水平刚度,建立网架结构简化计算模型,并与整体模型的工作性能进行对比分析。计算结果显示,网架单独简化模型与整体模型相比,网架杆件轴力大小、跨中节点竖向位移和网架支座反力的大小相差较小,能够满足实际工程精度要求。运用本文提出的支座弹性刚度计算方法对网架单独建模计算,具有与整体模型计算相当的精度。 相似文献
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为实现人机共驾模式下智能系统对驾驶人换道决策的准确识别,将换道决策细分并提出了基于改进的极端梯度提升(XGBoost)的换道决策识别模型。以实车试验采集的自然驾驶数据作为输入,并采用滑动时间窗法确定识别时刻,建立各识别时间窗口下基于XGBoost的换道决策识别模型,同时运用交叉检验和网格搜索(GS)算法进一步提升模型性能,最后利用验证集数据评估所构建GS-XGBoost模型的识别性能,并与机器学习及深度学习模型进行对比。结果表明,所提出的模型在具体换道决策辨识上具有较好的实时性和准确性,且在1.8 s和1.6 s时间窗下的识别准确率最高,达到86.2%。 相似文献
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来晓宁 《辽宁省交通高等专科学校学报》2012,14(2):8-11
本文结合本溪市水塔路(东明路至北光路段)以及北光路(胜利路至永明路段)段旧沥青混凝土路面加铺沥青混凝土面层的工程实践,阐述了土工布和玻纤格栅的特性、防治反射裂缝的作用机理、施工方法、注意事项及经验体会。 相似文献
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梁格法是一种准确、简便的曲线梁桥计算分析方法。对梁格法分析箱形桥梁结构的思路作了论述,介绍梁格法的网格划分原则及纵横梁格的截面特性的计算方法,并用midas civil 2010实体单元验证梁格法的可行性,以期为相关技术人员解决类似桥梁的挠度计算方面的问题提供参考。 相似文献
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城市交通信息服务作为智能交通系统的重要组成部分,其发展大多处于分散重复的建设阶段。本文在分析了网格技术与代理技术各自的优势基础上,提出了基于代理的城市交通信息网格服务系统,并给出了结构模型。通过代理技术和网格技术的结合,整合现有资源提高城市交通信息的服务效率。 相似文献
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With the rapid increase of educational resources, how to search for necessary educational resource quickly is one of most important issues. Educational resources have the characters of distribution and heterogeneity, which are the same as the characters of Grid resources. Therefore, the technology of Grid resources search was adopted to implement the educational resources search. Motivated by the insufficiency of currently resources search methods based on metadata, a method of extracting semantic relations between words constituting metadata is proposed. We mainly focus on acquiring synonymy, hyponymy, hypernymy and parataxis relations. In our schema, we extract texts related to metadata that will be expanded from text spatial through text extraction templates. Next, metadata will be obtained through metadata extraction templates. Finally, we compute semantic similarity to eliminate false relations and construct a semantic expansion knowledge base. The proposed method in this paper has been applied on the education grid. 相似文献
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The paper addresses different uncertainty analysis methods commonly used for uncertainty quantification in Computational Fluid Dynamics (CFD) studies and compares a constant Courant–Friedrichs–Lewy (CFL) number based approach for uncertainty estimation to the ITTC recommended grid and time-independent procedures. Four different uncertainty estimation procedures are presented and discussed. To compare their performance and better understand CFD related uncertainty quantification in wave load simulations on offshore structures, the methods are applied to a case study of the wave loads on a fixed vertical cylinder. The numerical or CFD wave tank is generated using the open-source CFD toolkit OpenFOAM. Uncertainty is assessed for the case study using four different uncertainty estimation procedures for verification and later, validation is attempted by comparing the CFD results with experiments. The study concludes that a constant CFL number based uncertainty study provides more stable results and is better suited for uncertainty estimation in CFD than the ITTC recommended individual grid and time step uncertainty study. 相似文献
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