Forecasting demand for high speed rail

It is sometimes argued that standard state-of-practice logit-based models cannot forecast the demand for substantially reduced travel times, for instance due to High Speed Rail (HSR). The present paper investigates this issue by reviewing the literature on travel time elasticities for long distance rail travel and comparing these with elasticities observed when new HSR lines have opened. This paper also validates the Swedish long distance model, Sampers, and its forecast demand for a proposed new HSR, using aggregate data revealing how the air–rail modal split varies with the difference in generalized travel time between rail and air. The Sampers long distance model is also compared to a newly developed model applying Box–Cox transformations. The paper contributes to the empirical literature on long distance travel, long distance elasticities and HSR passenger demand forecasts. Results indicate that the Sampers model is indeed able to predict the demand for HSR reasonably well. The new non-linear model has even better model fit and also slightly higher elasticities.     

基于秘密共享的高效RFID安全协议

文章介绍了基于秘密共享的RFID协议的工作流程,并从用户隐私、位置追踪、数据篡改、重放攻击、相互认证、防伪造、中间人攻击、前向安全性、数据库同步等方面探讨了协议的安全性,同时对比分析了协议的效率及成本。结果表明,该协议具有使用简便、安全性能好、效率高、成本低的优点。     

浅谈公路施工企业标后预算管理

标后预算即施工预算,也就是项目的成本预算,它是项目成本管理的主要依据。主要介绍了公路施工企业标后预算的作用、编制依据、编制方法和管理流程。     

浅析公共交通企业财政补贴机制

优先发展城市公共交通,保障城市公交企业可持续发展,迫切需求研究适合我国国情的城市公交财政补贴测算方法.文章明确了公交企业财政补贴机制的基本依据和原则,合理界定财政补贴的范围、方式和资金来源,建立基于公交企业成本规制的财政补贴机制,为建立政策性亏损补贴机制提供依据.     

Reduction of capacity and projected costs associated with seat belt installation on school buses

This study examines the potential effects the installation of seat belts on school buses would have on the fleet capacity in Alabama and the resulting cost implications. The study also documents the myriad research studies and professional opinions offered on the potential safety effects of equipping school buses with safety restraints/seat belts. Four seat configurations for the school buses were analyzed. The first configuration represents the most common current bus seating configuration without seat belts, 3 seats on each side of the aisle and 12 rows (3/3-12). The physical space required for seat belt hardware may result in a loss of a row of seats and may reduce the number of students seated per row. Thus, three more configurations were studied: loss of a row of seats (3/3-11), loss of one seat per row (3/2-12), and loss of both a row of seats and a seat per row (3/2-11). The capacity for each configuration for each bus using current pupil loads was determined. The costs associated with installation of seat belts, and purchase and operation of new buses were obtained. Should school bus seat belts become mandatory in Alabama, the results obtained in this study can be used by any school system to determine the optimum configuration for their pupils, which will identify the number of additional buses that must be purchased by the school system. This study found that many of the buses that would become overloaded due to seat belt installation and the resultant loss of seating will be carrying only a few excess pupils. Transportation supervisors may be able to handle such overloads by transferring these pupils to other buses or by adjusting their bus routes to minimize purchase of new buses. Additional suggestions for handling bus overloads were offered in the body of this report.     

公路施工准备阶段监理办建设问题初探

监理工程师办公室在公路工程施工准备阶段,既要完成工程前期施工准备阶段的监理工作,也必须完善监理机构的自身建设。监理机构自身建设涉及面广,工作相互交叉,往往在工作过程中考虑不足,甚至没有得到足够的重视,从而对今后的监理工作产生诸多不利影响。本章根据监理机构前期自身建设的特点,结合监理企业的现状,对施工准备阶段监理机构自身建设工作进行了探讨,并提出了解决方案。     

Imperfect reversibility of air transport demand: Effects of air fare,fuel prices and price transmission

There are recent evidence that air transport demand may not have a perfectly reversible relationship with income and jet fuel prices, as is assumed in most demand models. However, it is not known if the imperfectly reversible effects of jet fuel price are a result of asymmetries in the supply side, i.e., asymmetries in cost pass through from fuel prices to air fare, or of demand side behavioral asymmetries whereby people value gains and losses differently. This paper uses US time series data and decomposes air fare and fuel price into three component series to develop an econometric model of air transport demand that is capable of capturing the potential imperfectly reversible relationships and test for the presence or absence of reversibility. We find that air transport demand shows asymmetry with respect to air fare, indicating potential imperfect reversibility in consumer behavior. We also find evidence of asymmetry and hysteresis in cost pass-through from jet fuel prices to air fare, showing rapid increases in airfare when fuel prices increases but a slower response in the opposite direction.     

郑州市公交场站复合利用策略研究

公交场站是公共交通网络的关键节点,其复合利用模式可影响公交服务质量。本文从理论基础及应用策略两个层面对城市公交场站复合利用模式进行梳理,对公交场站复合利用的意义、模式及方法进行研究,建立集约高效的公交场站复合利用模式。以郑州市为例,验证了本文提出的公交场站复合利用模式能够适应这个时期的城市用地发展特征,提高公交场站服务能力,同时可减轻政府财政压力,发挥投资效益,可为政府部门制定公交场站复合利用模式提供参考。     

海上风电安装技术及装备发展现状分析

我国海上风能资源丰富,发展潜力巨大。文章总结分析了海上风电安装特点及存在问题;探讨了国内外现有风电安装船(或平台)类型、主要机具、关键结构及技术;并进一步提出了海上风电安装技术及设备发展趋势,为我国海上风电安装技术和装备发展提供借鉴和建议。     

应急状态下公路建设项目投资的控制实践

在汶川地震灾后恢复重建对口支援建设的大背景下,援建资金的运用受社会高度关注,必须提高项目造价控制和管理水平。以上海对口支援都江堰市蒲虹公路为研究对象,结合山区公路施工特点,从设计、合同、施工及结算等几个阶段,分析和总结了造价控制思路,采取的行之有效的措施,为援建项目和山区公路造价控制积累了经验,达到了有效控制造价的目的...