采用超级电容的燃料电池城市客车参数匹配和性能仿真

以一辆长12m的燃料电池城市客车为例,探讨了“燃料电池 超级电容”(FC C)驱动型式的特点。在提出的“FC C”动力系统结构基础上,讨论了整车的参数匹配问题,并建立整车仿真模型,对整车的动力和燃料经济性进行了仿真研究。研究结果表明,“FC C”动力系统能够满足整车的动力性要求,并且在燃料经济性方面优于国外同类车型。     

城镇排水系统设计、运行及管理经验探讨

按照专业规范设计的排水系统,在实际运行中往往难以达到预期效果.该文为此提出了改进雨水管道出水口和收水口、建设管道之间的连通管、建设住宅小区雨水管道等改进意见;对污水系统提出了检查井井底设置沉泥坑、检查井内设置闸槽、集中与分散相结合方式建设污水处理厂等建议.     

地铁盾构隧道下穿宁启铁路的变形影响规律及控制技术

地铁隧道在下穿既有铁路时,保证其安全运营是施工中的关键问题之一。为保证南京地铁S8线某段盾构隧道下穿宁启铁路桥涵的安全,通过建立FLAC三维数值模型进行计算分析,并将监测结果和计算结果进行对比分析,得出以下结论:1)盾构下穿期间,在对地层进行水泥注浆、加固土体的同时,还应加强同步注浆和二次注浆,设定施工控制区域,并将盾构施工参数精确到每一环。2)地层加固前后的地表变形规律,采取加固措施可以将地铁下穿带来的铁路沉降影响降至0.7 mm。3)根据现场情况制定了地表变形监测方案。结果显示,路基地表沉降较之桥涵沉降值显著一些,但仍处于安全范围之内。     

高等级公路电渗法软基处理试验研究

通过对佛山市一环公路乐从段进行软基处理试验 ,取得了一系列重要技术数据 ,本文对电渗法软基处理作重点介绍 ,包括其设计参数 ,施工工艺及控制、监测与试验内容和试验成果分析等 ,并提出研究结论和建议。     

郑州市快速公交BRT首期工程设计总结

该文就郑州市快速公交首期工程结合设计、运营等情况进行了介绍,总结经验并探讨了快速公交与城市交通体系的关系。     

温州市域铁路S1线信号系统独立安全评估应用

概述独立安全评估的对象、目的,以及评估方与项目执行方之间的关系;以温州市域铁路S1线信号系统安全评估为例,围绕其新制式、新系统和高风险的特点,阐述了评估策略的确定;从危害分析与管理、阶段授权、流程审核及质量管理等方面介绍了评估实施过程.     

Vehicle routing with roaming delivery locations

We propose the vehicle routing problem with roaming delivery locations (VRPRDL) to model an innovation in last-mile delivery where a customer’s order is delivered to the trunk of his car. We develop construction and improvement heuristics for the VRPRDL based on two problem-specific techniques: (1) efficiently optimizing the delivery locations for a fixed customer delivery sequence and (2) efficiently switching a predecessor’s or successor’s delivery location during the insertion or deletion of a customer in a route. Furthermore, we conduct an extensive computation study to assess and quantify the benefits of trunk delivery in a variety of settings. The study reveals that a significant reduction in total distance travelled can be achieved, especially when trunk delivery is combined with traditional home delivery, which has both economic and environmental benefits.     

Getting around a license-plate ban: Behavioral responses to Mexico City’s driving restriction

License-plate-based driving restrictions are among the highest profile policies for local governments to address congestion and air pollution. Cities as varied as Sao Paulo, Paris, Tianjin, and New Delhi have enacted temporary or permanent restrictions to improve local air quality. Using household travel survey data and a research design based on the abrupt shift in how the policy applies to 10-year-old vs. 9-year-old vehicles, we evaluate the impact of Hoy No Circula, one of the earliest and most studied driving restrictions, in Mexico City. In line with previous studies, we find that Hoy No Circula has done little to reduce overall vehicle travel, but we reject the prevailing theory that its lack of success is due to perverse incentives for households to buy second cars. Instead, we highlight the range of other, less costly ways that people adjust behavior to avoid the restrictions. Although no single behavior dominates, most households — particularly those that own older, higher-polluting vehicles — do not use their car every weekday regardless of the restriction. As a result, it is relatively easy to shuffle travel from restricted days to unrestricted days and thus avoid the ban. Shuffling travel days is less costly, more immediately available, and far simpler for most households than buying a second car.     

大跨径钢桥桥面铺装层疲劳特性试验研究

利用有限元方法对某大跨径钢桥面铺装层进行力学分析,以此为依据,现场采样,进行了环氧沥青混合料与钢板的结合件的疲劳试验。结果表明,该大跨径钢桥采用环氧沥青混合料铺装是成功的,其使用寿命可达15 年以上。     

袖阀式劈裂注浆和动力固结法路基补强处理

结合工程实例,对道路下雨污水管槽回填密实度不满足设计要求而导致的路面开裂,采取袖阀式劈裂注浆法和动力固结法进行加固,并分析影响加固效果的原因以及总结值得吸取的经验教训。