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951.
路基横断面形式应与沿线自然环境相协调,避免因深挖、高填对其造成不良影响。根据公路等级、技术标准,结合当地地形、地质、水文、填挖等情况选用。高速公路、一级公路宜采用浅挖、低填、缓边坡的路基断面形式。由于填挖情况的不同,路基横断面的典型形式可以归纳为路堤、路堑和填挖结合三种类型。 相似文献
952.
以实际桥梁修复工程为例,基于钢支架的受力特点,有关主梁荷载向横桥向分配梁、贝雷梁、工字钢垫梁及钢管桩等的传递特点分析表明,该钢支架设计方案是成功的,可为类似工程提供借鉴。 相似文献
953.
合理的滑行面设计,是滑行艇设计中的关键问题.利用CFD软件FLUENT对滑行艇简化模型的流场进行数值模拟,得到简化模型的压力分布细节,并由此对滑行艇的滑行面进行改型,通过改型调整航态和艇底的水动压力分布,达到降低船舶阻力的目的.改型前后的实验结果显示:改型后滑行阻力与原型相比减小7%.研究表明:利用通用软件进行船舶流体力学的研究,是一个较为有效的方法;另外,通过合理布置滑行面可有效减小滑行艇滑行阻力. 相似文献
954.
955.
结合河南省某高速公路桥梁伸缩缝的施工实例,介绍伸缩缝的施工工艺及质量控制要点,总结施工注意事项,可供同行参考。 相似文献
956.
957.
从界定交通环境系统的界壳论域出发,分析交通环境系统的界壳支撑结构和界壳行为,定义界壳开放度、界壁抵抗力以及界门开关速度、界门交换率等描述交通环境系统界壳功能的参数。研究表明,界壳论在降低路网建设对交通环境系统破环程度、调控交通污染排放与环境自净化能力的协调运行等方面具有较好的应用前景。 相似文献
958.
This paper presents an eye and iris detection algorithm for human facial images. The authors combine three features of the eye to develop the algorithm: 1) the pixels surrounding the eyes are more variable than other parts of the face; 2) eye pixels are darker than their neighbors; 3) eyes often exhibit radial symmetric properties. Through the first feature, two rough regions of both eyes are detected on the face. Eye masks are then formed based on the second feature, and a fast radial symmetry transform is applied to the two rough regions of both eyes. Finally, accurate iris centers are located by searching the maximum value of the radial symmetry transform results. Using 450 human facial images from the Caltech face database, experiments show that the success rate of the proposed method is 91.7%. The effectiveness of the method was also verified through detection of video frames. 相似文献
959.
A balancing method was used to build a DC partial discharge (PD) testing circuit for electrical equipment, and a narrow-band detection system was designed using detection resistance and a filter. After signal accessed a high-speed digital acquisition (DAQ) card, the system was triggered to extract a single partial discharge (PD) signal. To eliminate the interference pulses caused by power supply ripple, etc., the time domain and frequency domain features of pulses were extracted. Based on the features, cluster analysis was used to exclude interference pulses. Two-dimensional and three-dimensional histograms were obtained by use of the Δt method. Then, 22 discharge statistical operators were calculated for the two-dimensional charts. Lastly, the defective system is capable of PD detection in electrical equipment. 相似文献
960.
Access to any development is a connection between the buildings and urban roadways. The impact of access on urban roads varies with location of the access. This paper studies the impact of access to large buildings on the surrounding road network by exploring traffic conflicts based on the configuration of the access. The concept of conflict intensity is introduced in this study as a new evaluation indicator to evaluate the traffic conflict triggered by the presence of access. The results show that the greater the speed, the greater the conflict intensity of access. Meanwhile, a similar situation exists when other variables (e.g., conflict angle or the number of conflicts) change. The larger the conflict intensity, the more dangerous the access. Results from this study can help developers and traffic engineers choose suitable locations of access and organize the traffic in a logical manner. 相似文献