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991.
Precise estimation of the capacity for right‐turn traffic (comparable to left‐turn traffic in the USA) is of great importance to determine signal phasing schemes at signalized intersections in Japan, where the left‐hand driving rule is valid. However, in most signal timing procedures across the world, the lost time of right‐turn traffic is simply determined by the duration of intergreen intervals and thus lacks considerations of various signal phasing and driver behavior. Meanwhile, sneakers per cycle are usually applied to account for the number of drivers completing right turns during the effective red portion of the clearance‐and‐change intervals. As a result, an initial cycle length must be hypothesized in order to assess the total number of sneakers within the analysis period. Consequently, a time‐consuming iterative calculation process often becomes necessary. Therefore, the present study aims to develop a new lost time estimation method for right‐turn traffic to overcome the aforementioned drawbacks. Lost times of right‐turn traffic under three conventional phasing plans are theoretically formulated on the basis of a time–space diagram and shock‐wave theory. The new method is validated using field data, with case studies of its application in the signal timing procedure. Results indicated that the proposed method is capable of offering more accurate estimation than conventional approaches, which leads to shorter cycle length and simplifies signal timing process by eliminating an iterative check to determine the number of sneakers. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
992.
Since the Taiwan High Speed Rail operations, Taiwan's transportation market entered into a new era. Because of its competitive service of speed, convenience, environmental concerns and comfort, the High Speed Rail has not only made significant changes but has played a significant role in Taiwan's transportation. However, Taiwan now is an aging society. Due to the physical constraints among the elderly, demands to redesign the traffic system and maintain transportation safety are essential considerations. In the current market, Taiwan's transportation construction is facing fewer barriers; however, it must still improve, especially considering the health of the elderly. Thus, this study investigates elderly passengers' demands and further examined the relationships among service quality, corporate image, customer satisfaction, and behavioral intention. According to empirical analytical results based on structural equation modeling (N = 341), satisfaction directly affected travel behaviors, while service quality and corporate image played indirect roles. In addition, service quality plays a significant role on the effect of satisfaction. This study provides empirical evidence to indicate the quality of the accessible environment affects not only the effectiveness and efficiency of service quality, but also, the corporate image. The results provide valuable references for critically managing the elderly's usage of the high speed rail transportation service. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
993.
Abstract In this study, we focus on the development of work team routing/scheduling models incorporating stochastic travel and repair times. Robust and expected optimization concepts, combined with a time–space network technique, are used to develop the models. We perform numerical tests based on operational data for Taoyuan County in Taiwan. The test results show the good performance of the models. 相似文献
994.
西安地铁四号线是西安市轨道交通线网中的十字骨架,是线网中的骨干线路,它穿越了14条活动的地裂缝带.为进一步研究西安地裂缝,给地铁线路沿线地裂缝的防灾减灾提供科学依据,本文通过野外地质环境和地质灾害调查,着重查明了西安地铁四号线沿线的14条地裂缝的发育特征;并根据近些年的监测成果资料对地裂缝的活动性进行了分析总结,预测了其活动趋势;采用定量计算的方法确定了地裂缝对地铁线路的影响范围,并在综合分析地铁线路危害特点的基础上确定了地裂缝与线路相交段的危险性等级,最终将与地铁四号线相交的地裂缝划分为Ⅰ级、Ⅱ级、Ⅲ级三个等级.地裂缝灾害是西安主要的地质灾害,在地铁建设中要给予高度重视. 相似文献
995.
分析纯电动汽车电机驱动特性,建立纯电动汽车动力性计算模型;分析纯电动汽车行驶中主电路负载电流变化,给出相关计算方法;研究影响纯电动汽车续驶里程的因素,建立其续驶里程计算模型. 相似文献
996.
在组合结构已有的理论研究和实验基础上,通过引入钢-混凝土结合箱梁翼缘板剪力滞翘曲位移函数,推导了考虑剪力滞效应作用的结合箱梁曲率公式,探讨了剪力滞效应对梁体变形的影响,提出了结合箱梁剪力滞系数修正法,并结合实例验证该方法的精度. 相似文献
997.
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999.
利用高速摄影技术,对空气辅助和无空气辅助两种典型的柴油机氮氧化物(NOx)选择催化还原(SCR)尿素喷射系统,在常温常压下的尿素喷雾特性和在定容燃烧弹内对空气辅助喷射系统在不同温度下的尿素喷雾特性进行了可视化试验研究.结果表明,随着尿素溶液喷射速率的提高,空气辅助喷射系统的喷雾贯穿距增大,喷雾锥角变小,且随着环境温度的上升贯穿距明显减小,发生碰壁现象的可能性减小;而无空气辅助喷射系统的喷雾形态则基本不受喷射速率的影响.应用粒子动态分析仪(PDA)对两种喷射系统的喷雾粒径分布进行的测试结果表明,空气辅助喷射系统的喷雾液滴粒径明显小于无空气辅助喷射系统,因而具有良好的喷雾特性. 相似文献
1000.