多优先级多车种动态应急交通网络反流策略研究

危化品爆炸泄漏和火灾爆炸等局部突发事件下,疏散车辆与救援车辆在路网上通行的优先级具有差异性。为研究多优先级多车种动态应急交通网络协调优化问题,本文根据多车种的优先级差异性,松弛路段传输模型,模拟疏散和救援交通在路网上的动态加载过程,引入交叉口冲突转向消除与道路反流约束;考虑到优先通行车辆的反流策略会占用低优先级车辆的道路通行能力,设置救援交通的逆行路段数限制。设计分阶段优化方法求解多优先级多车种动态应急交通网络协调优化的多目标混合整数线性规划模型(MPCDETN-MMILP)。最后,以 NguyenDupuis路网为例,分析优先通行车辆使用的逆行路段数对疏散和救援交通的影响。算例结果表明：救援交通逆行路段数和对救援车辆迅速到达受灾区域的提升存在上限,且这种提升趋势是逐渐变缓的,而对疏散车辆迅速到达安全区域的抑制呈现波动式的增加趋势;救援交通逆行路段数对救援优先的疏散和救援交通运行优化效果有较大协调作用;连接受灾区域和外部救援场站,且可构成最短径路的路段更会被选择为救援交通逆行路段。     

Bus control strategies in corridors with signalized intersections

This paper proposes a new dynamic bus control strategy aimed at reducing the negative effects of time-headway variations on route performance, based on real-time bus tracking data at stops. In routes with high demand, any delay of a single vehicle ends up causing an unstable motion of buses and producing the bus bunching phenomena. This strategy controls the cruising speed of buses and considers the extension of the green phase of traffic lights at intersections, when a bus is significantly delayed. The performance of this strategy will be compared to the current static operation technique based on the provision of slack times at holding points. An operational model is presented in order to estimate the effects of each controlling strategy, taking into account the vehicle capacity constraint. Control strategies are assessed in terms of passenger total travel time, operating cost as well as on the coefficient of headway variation. The effects of controlling strategies are tested in an idealized bus route under different operational settings and in the bus route of highest demand in Barcelona by simulation. The results show that the proposed dynamic controlling strategy reduces total system cost (user and agency) by 15–40% as well as the coefficient of headway variation 53–78% regarding the uncontrolled case, providing a bus performance similar to the expected when time disturbance is not presented.     

双馈电机变速恒频风力发电技术概述

文中简要介绍了双馈电机变速恒频风力发电系统的基本结构和运行原理,对双馈电机变速恒频风力发电技术进行了概述,其中包括交流励磁电路拓扑、控制策略、并网控制,展望了双馈电机变速恒频风力发电技术的发展趋势.     

国内外舰船焊接技术概况及发展建议

本文概要介绍了国内外水面舰艇焊接技术的现状与发展趋势,在此基础上提出了发展我国水面舰艇焊接技术的几点建议。     

Barriers and strategies in listening comprehension

A variety of barriers to listening comprehension are illustrated in this paper. They are analyzed respectively and several effective strategies are also presented afterward. The barriers to listening are those of psychological quality, language knowledge, cultural background, Chinese interference and so on. The strategies should be as follows: training students' psychological quality, strengthening the teaching and learning of language knowledge, comparing cultural differences, using student-centered teaching method and combining intensive listening and extensive listening.     

收费公路存在的问题及治理对策

贷款修路,收费还贷”政策经过多年实践证明,较好地缓解了公路建设资金短缺的矛盾,极大地加快了公路建设的步伐。收费还贷公路的建设,对促进我国交通公路事业的发展,提高公路网整体水平,缓解交通拥挤状况起到了重要作用。     

Use of the analytic hierarchy process to evaluate transit fare system

The transportation fare system influences the mobility of a region and the life quality of its inhabitants. This study aims to evaluate a region's optimal fare system by using the analytic hierarchy process, based on a survey among transportation experts, divided into three categories: operators, professors/consultants and government officials. The results are presented divided by category and overall, and the performance of the most important relative criteria to establish a fare system is determined. The most important criterion according to all the selected experts was the fare price, with 21.5%. The fare system determined as the best was distance/zone (31.1%) and the worst was a flat fare system (7.2%). In addition, we show the influence of the fare price criterion in each fare system through sensitivity charts and highlight its importance for all three groups of experts to evaluate the fare system.     

理想AND/OR图搜索策略的推广

SUB和COM是专家系统推理网络图中常见的关系算子，AND和OR分别是SUB和COM算子的特例．建立在理想AND／OR图上的半景搜索法和最大优势搜索法可以推广到包含SUB和COM算子的理想非AND／OR图的搜索，而最大超越搜索法则可推广到包含回路结构的非理想AND／OR图的搜索．     

轮机英语教学中的纠错策略

语言教学者的纠错策略一直是语言教学研究的热点问题,第二语言教学中也出现了基于不同错误类型的纠错方法。本文以错误分析理论为依据,探讨了轮机英语教学中常见错误的应对策略,包括对错误应持的态度,纠正错误的原则、策略和技巧,以及实施补救性教学的方法,并建议轮机英语教师遵循IMO的Model Course倡导的交际法原则,在轮机英语教学过程中为学生提供有益的纠错和补救性教学,改进教学效果。     

浅谈自行车对城市交通的影响及发展对策

发展自行车交通与完善城市交通体系是密不可分的。建立安全、畅通、高效的交通网络系统，方便居民的出行．是目前及今后制定自行车交通发展战略应着重考虑的问题。