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51.
为了克服舰炮最佳表尺分配决策难以实用化的难题,利用门限控制原理、最佳表尺均匀分配原理以及黄金分割搜索算法,提出简单且易于实用化的编队舰炮对岸破坏射击表尺分配优化算法,为相关领域研究提供参考意见。 相似文献
52.
Henry X. Liu Xinkai Wu Wenteng Ma Heng Hu 《Transportation Research Part C: Emerging Technologies》2009,17(4):412-427
How to estimate queue length in real-time at signalized intersection is a long-standing problem. The problem gets even more difficult when signal links are congested. The traditional input–output approach for queue length estimation can only handle queues that are shorter than the distance between vehicle detector and intersection stop line, because cumulative vehicle count for arrival traffic is not available once the detector is occupied by the queue. In this paper, instead of counting arrival traffic flow in the current signal cycle, we solve the problem of measuring intersection queue length by exploiting the queue discharge process in the immediate past cycle. Using high-resolution “event-based” traffic signal data, and applying Lighthill–Whitham–Richards (LWR) shockwave theory, we are able to identify traffic state changes that distinguish queue discharge flow from upstream arrival traffic. Therefore, our approach can estimate time-dependent queue length even when the signal links are congested with long queues. Variations of the queue length estimation model are also presented when “event-based” data is not available. Our models are evaluated by comparing the estimated maximum queue length with the ground truth data observed from the field. Evaluation results demonstrate that the proposed models can estimate long queues with satisfactory accuracy. Limitations of the proposed model are also discussed in the paper. 相似文献
53.
探地雷达在隧道衬砌施工质量控制中的应用研究 总被引:2,自引:2,他引:0
就探地雷达在隧道衬砌质量检测中的适用性、检测项目确定、测线布设、参数设置、安全性等问题进行了探讨和阐述,并以实际工程案例说明探地雷达可随时对衬砌进行准确、非破坏性的检查,宜作为施工质量控制的手段. 相似文献
54.
关维赴 《辽宁省交通高等专科学校学报》2009,11(4):43-46
本文阐述了企业文化在企业管理中的导向、凝聚、激励、约束和辐射功能,对企业发展具有指导意义。 相似文献
55.
针对当前铁路配电网电力远动系统以监控为主,调度端缺少完善的故障分析软件,使得运行人员不能及时判断、排除故障,影响列车行车安全问题,提出在供电段调度中心构建铁路配电网故障信息管理及诊断系统,作为铁路电力远动系统的高级应用软件。该软件在原有的SCADA系统平台上运行,能够完成铁路配电网信息管理、故障特征提取以及故障综合分析,为电力调度运行人员提供辅助决策支持。具体介绍了铁路配电网故障信息管理及诊断系统的构成原理、功能特点、模块组成以及关键算法。 相似文献
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X. D. Wu S. G. Zuo L. Lei X. W. Yang Y. Li 《International Journal of Automotive Technology》2011,12(5):671-677
The purpose of this study was to effectively identify parameters for a LuGre friction model based on experimental measures.
In earlier work related to this study (Yang et al., 2009), which was based on the characters of polygonal wear (Sueoka and Ryu, 1997), we showed a frictional vibration model
for a mass on a moving belt. This model reflected lateral vibrations caused by velocity and toe-in angle. An important aspect
of the present study is the improved friction model. A previous friction model, which divided the process into four parts,
expressed the sable excited vibration well but failed to reflect the hysteresis loop change when vehicles accelerated or decelerated
continuously. A LuGre friction model can solve this problem, but several model parameters must be obtained experimentally.
We measured contact width and length of tires as vertical pressure changed; this provided a theoretical basis for apparent
stiffness of a unit of tire tread. Based on tire data from Bakker E’s article in a SAE paper from 1987, we identified the
Stribeck exponent and Stribeck velocity in LuGre. Then, the results were implemented in a vibration system that verified the
rationality of the data. 相似文献
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