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121.
The Taiwan High Speed Rail (THSR) has recently added three additional stations to its original network. Although the three additional stations can improve accessibility to the system, these new stations can present difficulties in the transportation planning process, particularly for planning of train stops. The additional stations may benefit some passengers, but may also lengthen the travel time for the other passengers. Therefore, the main challenge faced by THSR is finding an efficient way to design appropriate stopping patterns. Past studies on stop planning usually adopted meta‐heuristics or decomposition methods to solve this complex problem. Although these solution techniques can improve solution efficiency, none of them can guarantee the optimality of the solution and capture the transfer movement of different stopping patterns. In this research, we proposed an innovative network structure to address complex stop planning problems for high‐speed rail systems. Given its special network structure, two binary integer programming models were developed to simultaneously form and determine the optimal stopping patterns for real‐world THSR stop planning problems. An optimization process was also developed to accurately estimate the station transfer time corresponding to the variation in stopping patterns and passenger flow. Results of the case studies suggest that the proposed binary integer programming models exhibit superior solution quality and efficiency over existing exact optimization models. Consequently, using this stop planning optimization process can help high‐speed rail system planners in designing optimal stopping patterns that correspond to passenger demand. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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对客车侧倾及侧翻的试验及评价方法进行介绍和分析,在此基础上提出一种主被动安全综合评价方法,为企业进行客车安全性的设计和评价提供参考。 相似文献
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对高压共轨柴油机稳态与瞬态工况下的微粒排放粒度分布进行了实验研究。结果表明,高压共轨柴油机排气微粒粒径大部分处于250nm以内,超细微粒占绝大多数。稳态工况下,随负荷增加微粒数量浓度分布曲线峰值逐渐向大粒径方向移动,大负荷工况下峰值开始进入积聚态区域。在瞬态工况下,微粒粒度分布曲线呈单峰形态,平均数量浓度分布峰值位于核态区域,峰值区间为15~25nm。在同一负荷(当量比0.5)下,稳态工况的核态微粒的数量、表面积和体积浓度均较稳态工况大幅度上升;随着瞬变率的增大,核态微粒数量浓度增加而积聚态微粒数量浓度下降。 相似文献
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本文中对汽车的操纵稳定性控制系统中车辆失稳的判断进行研究。采用能量法推导了车辆的失稳动能与纵向运动动能方程式,并将二者的比值定义为失稳能量比,而基于相平面法提出了车辆的稳定性判据,以判断车辆的行驶稳定状态。最后使用Vedyna软件进行车辆的仿真分析,结果验证了该稳定性判断的有效性。 相似文献
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Abstract The Internet service attributes desired by shippers were examined as well as a model that seeks to explain the intention of shippers to use Internet services in liner shipping. Using data collected from a survey of a group of shippers in Taiwan, the relationships among the constructs in the model were tested, namely: perceived usefulness, perceived ease of use, security and use intention. The results suggest that shippers perceive tracing to be the most important service attribute of Internet services, followed by checking for customs clearance, vessel schedules and electronic document services. The findings indicate that perceived ease of use is the major factor affecting the intention of shippers to use Internet services, and that perceived ease of use has a strong positive effect on perceived usefulness. The results also indicate that security has a positive effect on a shipper’s perception of ease of use. However, the influence of security on use intention and perceived usefulness was not supported in this study. The theoretical and practical implications of the findings on the intention of shippers to use Internet services in liner shipping are discussed. 相似文献
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以山西省忻州市跨云中河景观桥梁工程为背景,从忻州自然状况、人文历史景观等方面出发,阐述了3座景观桥梁方案设计的基本思路;从建筑设计理念及表现手法、夜景照明设计、功能与人性化统一等方面,对契合地域特征的桥梁方案进行了论述;介绍了3座景观桥梁的技术标准、总体布置和结构设计。 相似文献
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