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101.
Modeling traffic operation at signalized intersections without explicit left‐turn yielding rules with an enhanced cell transmission model 下载免费PDF全文
This paper presents an enhanced cell transmission model (CTM) to capture traffic operation at signalized intersections without explicit permissive left‐turn yielding rules (i.e. aggressive permissive left‐turn maneuvers may not necessarily yield to opposing through traffic), which can be widely observed in many developing countries. Different from previous studies that focus on traffic dynamics on approaching links, this study contributes to modeling traffic operations within the intersection. A novel cell transmission framework with various types of virtual cells is proposed to model the dynamics of traffic movements from approach to exit. The unique phenomenon of competitive occupying of the conflict point between the left turn and opposing through movements is modeled. The cell state indicating its blockage is proposed to capture the dynamic queue formulation and dissipation and to evaluate the operational traffic performance at the intersection. Field validation results show that the proposed model can capture the operation of traffic at signalized intersections without explicit permissive left‐turn yielding rules with significantly higher level of accuracy than traditional traffic flow models. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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本文详细介绍了等截面多风口等量排风长管道内压力分布基本式理论推导和风口开度调节计算方法,并根据实际地下工程测定数据验证其理论计算可靠性,可以供地下工程设计计算和工程调试中作借鉴和参考。 相似文献
104.
This paper studies the fault diagnosis of singular stochastic systems. The probability distribution of output is measured
by probability density functions (PDFs), which are modeled by a square root B-spline expansion. An adaptive nonlinear observer
is proposed to estimate the size of the fault occurring in systems. Furthermore, the linear matrix inequality (LMI) approach
is applied to establish sufficient conditions for the existence of the observer. Finally, the simulation results are given
to indicate the method for diagnosing the fault. 相似文献
105.
胡泽盛 《现代城市轨道交通》2014,(2):55-58
从总体策划、演练准备、演练实施、总结评估等方面系统介绍了西安地铁1号线运营演练实践过程,提炼出演练项目确定、场景设计、演练组织、方案设计、评估模式的创新之处,丰富了城市轨道交通运营演练的实践经验和技术体系,为国内同行提供借鉴与指导。 相似文献
106.
结合高速磁浮线路轨道的特点及其车辆特征,对车站内线路的主要技术标准,如纵断面坡度、横坡角、平面曲线半径等进行了研究,对车站内列车通过的速度与平面曲线半径的关系作了分析,并提出了相应的研究结论. 相似文献
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Radar target signals and chaff cloud jamming signals have different characters by the wavelet transform. The wavelet coefficients
of radar target signals are highly correlated with its near-and-near-scale wavelet coefficients, however the correlativity
between the wavelet coefficients of chaff cloud jamming signals and its near-and-near scale wavelet coefficients is less significant.
Based on the binary-base discrete wavelet transform and the correlation algorithm, the method of target entropy to estimate
standard variance of the jamming signals and each scale is proposed to ensure reasonable threshold, to suppress chaff cloud
signals and finally to reconstruct mixed signals by the improved spatially selective noise filtration (ISSNF) method. The
extensive simulation results show that the proposed method can availably suppress chaff cloud jamming and decontaminate target
echo. 相似文献
109.
结合工程实例介绍了后张法预应力在桥梁施工中的应用,主要包括孔道设置、穿柬、张拉、压浆等关键工序的施工和质量控制.以及千斤顶活塞伸长值的理论计算方法.提出确保桥梁结构物满足规范要求的具体措施。 相似文献
110.