The spatial distribution of journey-to-work trips in Greater London

Although a great deal is known about the distribution of homes and the distribution of workplaces in Greater London, the spatial relationship between them is less well understood. Using 1966 census data, the authors try to give a simple visual picture of this relationship, and to assess the relative travel intensities which would arise at different points in London from commuter trips, assuming straight line routing.The results show firstly that a large proportion of the population work quite close to their homes, with radial travel towards the city centre being only slightly more prominent than other directions of movement. The remainder tend to work near the city centre and to travel much longer distances. Secondly, relative to various annuli at 2 km increments centred on Charing Cross, the amounts of through traffic expressed as a proportion of the totals are roughly constant for radii between 4 and 14 km. Thirdly, people's choice of home in relation to their workplace is, on the whole, quite efficient, since it gives rise to a total amount of travel which is much closer to the theoretical minimum than it is to the amount corresponding to a random choice of homes from the available stock.     

Relationship between proximity to transit and ridership for journey-to-work trips in Chicago

The use of privately owned vehicles (POVs) contributes significantly to US energy consumption (EC) and greenhouse gas emissions (GHGe). Strategies for reducing POV use include shifting trips to other modes, particularly public transit. Choices to use transit are based on characteristics of travelers, their trips, and the quality of competing transportation services. Here we focus on the proximity of rail stations to trip origins/destinations as a factor affecting mode choice for work trips. Using household travel survey data from Chicago, we evaluate the profile of journey-to-work (JTW) trips, assessing mode share and potential for more travelers to use rail. For work trips having the origin/destination as close as 1 mile from rail transit stations, POVs were still the dominant travel mode, capturing as much as 61%, followed by rail use at 14%. This high degree of POV use coupled with the proportion of JTW trips within close proximity to rail stations indicated that at least some of these trips may be candidates for shifting from POV to rail. For example, shifting all work trips with both the origin/destination within 1 mile of commuter rail stations would potentially reduce the energy associated with all work-related POV driving trips by a maximum of 24%. Based on the analysis of trips having the origin and destination closest to train stations, a complete shift in mode from POV to train could exceed CO₂ reduction goals targeted in the Chicago Climate Action Plan. This could occur with current settlement patterns and the use of existing infrastructure. However, changes in traveler behavior and possibly rail operation would be necessary, making policy to motivate this change essential.     

道路运输行业安全监管现状分析及对策研究

结合道路运输行业安全监管现状,从道路运输行业安全监管职责和内容、监管方式、安全检查方面对道路运输行业安全监管存在的问题进行分析,并有针对性的提出了相应的建议和对策。     

插电式混合动力电动汽车应用现状分析

文章简述了插电式混合动力汽车的优势,分析了插电式混合动力汽车串联式、并联式和混联式的动力机构,以及插电式混合动力汽车的工作模式.在此基础上,探讨了插电式混合动力汽车应用所面临的问题以及相应的应对措施.     

Employment status and commute distance of Canadians with disabilities

Alleviating the disability challenges experienced by people with impairments is increasingly seen as an important step towards building more inclusive societies. The very definition of disability has evolved to shift the burden from people with impairments to perform at “normal” competency levels and towards a fuller recognition of the ways that society can either build or tear down barriers that hinder their full participation in society. The objective of this paper is to investigate the factors that act as facilitators or barriers to participation by people with impairments. Specifically, the study is conducted within the context of employment status and commute distance, two outcomes indicative of the ability of individuals with impairments to engage society. Analysis is based on Canada’s 2006 Participation and Activity Limitation Survey, a post-censal survey that collects information on various aspects of disabilities for a representative sample of Canadian society. The results, based on a probit model for employment status and a regression model for commute distance, provide insights into the personal, economic, and living space factors that affect the probability of being employed and traveling longer distances.     

Immigrant status and commute distance: an exploratory study based on the greater Golden Horseshoe

With 8.76 million residents in 2011, the population of Southern Ontario’s Greater Golden Horseshoe (GGH) has grown dramatically over the past decades, driven by net domestic in-migration and immigration. Corresponding to its growth in population, commuting distances and times within the region have grown as well. Yet, despite the number of immigrants that the region attracts on a yearly basis, there is comparatively little information on commute distances. Consequently, this paper examines commuting distance amongst immigrants in the GGH. Specifically, it evaluates commute distance by immigrant status (immigrants and native born), along with how commute distance differs by arrival cohort and ethnic and racial population groups. Results indicate that commute distance increases with increasing duration of residence, with differences by race and ethnicity.     

国内地铁盾构区间隧道管片结构设计的现状与发展

近几年国内地铁区间盾构隧道的结构设计相对于早期的上海地铁一号线又有了一定的发展,随着盾构法普及后工程条件的变化出现了一些新的管片形式和结构分析方法,在借鉴国外经验的基础上将逐步做到与国际接轨.     

Traffic reduction by telecommuting: A status review and selected bibliography

Telecommuting is defined as a subset of teleworking. Two main forms of telecommuting (home and regional center) are described. The means by which these forms of telecommuting may alter urban transportation patterns are outlined, followed by a review of the empirical evidence to date on the impacts and usefulness of telecommuting. Factors affecting the diffusion rate of telecommuting are discussed, including the commuting environment, technological sufficiency, technological familiarity, the social aspects of work, other telecommuter motivations, management issues, legal and regulatory barriers and incentives, and labor entitlement issues. A brief reference to other work in progress is followed by a set of forecasts of possible telecommuting futures.     

The status of German railway operations management in research and practice

The German railway operations management uses probabilistic and simulation methods in research and practice. The probabilistic methods are based on queuing theory. There are synchronous or asynchronous algorithms for the simulation of time tables, schedule, operation, and disposition. Models were also developed for the simulation of the operation in many parts of the network for the connection between the structure of the track and the capacity of lines and stations, for the evaluation of operating cost depending from the quality of service, and for the design of integrated timetables.     

Direct to your destination: the size,scope and competitive status of express coach carriers in the United States

The advent of express coach bus lines offering guaranteed seating and emphasizing curbside pickup and drop-off is contributing to a revival in intercity bus travel in the United States. Relatively little is known, however, about the scale and geographic scope of these carriers or the competitive landscape in which they operate. To fill this void, this study evaluates the service networks operated by the two largest express coach operators in the country, BoltBus and Megabus, and evaluates a data set of 4775 fares sold on megabus.com. The results show that these carriers cumulatively serve 127 intercity segments and operate about 52.9 million bus miles per year. Together, these carriers have grown to about one third of the size of Amtrak, with Megabus and BoltBus providing 3.3 billion and .69 billion seat miles of service, respectively, compared to Amtrak’s 12.8 billion. With respect to the types of routes it serves and the competition it faces, Megabus has evolved into a carrier quite different than Boltbus; more than one third of Megabus’ bus miles are operated on segments without Amtrak service, while virtually all of BoltBus’ miles face this competition. The analysis of Megabus’ pricing shows that fares rise modestly within 2 weeks of departure, while the per-mile costs are much less ($.08/mile) for 300–399 mile trips than for those 50–99 miles ($.22/mile). Nevertheless, the dispersion of fares tends to fall as the departure date nears, regardless of distance. Together, these prominent bus lines serve 66 of the 100 most heavily traveled U.S. city pairs that have characteristics suitable for intercity bus service—which is more than Amtrak. With further growth on the horizon, planners, federal regulators, and researchers should collaborate on establishing reporting requirements for this expanding sector.

     

船舶压载舱沉积物接收处置现状、问题及履约管理对策

《国际船舶压载水和沉积物控制与管理国际公约(2004)》要求妥善处理和处置压载舱沉积物,以防止有害生物入侵。为研究履约现状,选取13家从事压载水沉积物清理、接收及处理作业的修船厂进行了系统调研,结果表明普遍存在防污染措施不全、接收处理作业不规范、接收设施技术标准缺失、管理要求不明确等问题。在分析压载水沉积物的来源、危害、产生量等特性的基础上,结合公约和国内要求,从标准规范完善、监管部门协作、接收设施配套、公约法规宣贯和科技研发支撑等方面分析提出了履约对策。研究成果为有关压载水沉积物相关标准规范、技术政策的制定提供参考,有助于加强压载舱沉积物防污染管理,提升国际公约履行水平。     

Assessment of hub status among Asian ports from a network perspective

This paper proposes a novel network-based hub port assessment (NHPA) model through explicit formulations of connectivity and cooperation indices. Such a model is useful for port operators and policy makers to evaluate the relative influences of various quality characteristics from which carriers base their port choices on and identify port partners. Key insights can be obtained for port authorities to improve their port infrastructures and operations to achieve a competitive and sustainable hub port status. Three comprehensive case studies are conducted to assess the current standings and potentials of major Asian ports within networks of major carriers.     

Household structure and gender differences in travel time: spouse/partner presence,parenthood, and breadwinner status

Despite having more similar roles at work and home than ever before, US men and women continue to exhibit different travel behavior. An open question is whether the remaining gender differences in travel differ by traditional and emergent aspects of household structure such as spouse/partner presence, parenthood, and breadwinner status. Using data from the 2003–2010 American Time Use Survey, this study offers a unique, empirical travel time analysis of metropolitan workers stratified by household structure. Results show that gender differences in travel time respond to multiple aspects of household structure in complex and interactive ways. Gender difference in work travel time is only observable when spouse/partner presence and parenthood interact, i.e., in couple households with children. Gender difference in household support travel reacts to parenthood but not spouse/partner presence. Gender difference in travel time between employed females and employed males in single-breadwinner couples is no different from gender difference in double-breadwinner couples. The results call for policy initiatives and research inquiries that pay greater attention to the large gender disparities in work travel in couple households with children and the large gender disparities in household support travel in all households with children including single-parent households. Although incapable of ruling out the influences of internalized gender differences (e.g., preference theory) and gendered structural contexts (e.g., labor market segmentation), the findings provide clear evidence that traditional gender roles and relations remain operative in contemporary households in the US.     

我国海洋生态环境损害程度评价技术发展现状

本文通过对目前海洋生态环境的判定技术的综合分析,按海洋污染生态毒性损害、海洋污染对渔业资源的损害以及涉海工程对海洋生态环境损害三个方面入手,介绍了国内外的海洋生态环境损害程度评价技术的发展现状,并指出我国相关研究中存在的不足。     

公交支付方式及其效率调查分析

智能系统的广泛使用,带来了移动支付的普及。公交支付在传统IC卡和现金支付的基础上,加入了云闪付和二维码支付。为探究移动支付对公交支付效率的影响,基于杭州市公交发展现状,制定了公交支付情况的调查方案。通过对所选10、93、97公交线路的早、晚高峰和平峰的三天实地调查,采集视频数据并使用SPSS进行定量统计分析,发现公交乘客刷卡占62%、二维码占27%、云闪付占6%、现金占5%。当乘客提前做好准备时,刷卡支付时间为1.29 s,低于云闪付的1.42 s和二维码的1.65 s,而未准备好时用时分别为6.74 s、10.94 s、8.54 s。通过相关性和多元线性回归分析得出提前拿卡、上车掏卡、提前开二维码和上车开二维码四种支付方式对公交停留时间延长的影响最大。     

A review of the evidence for induced travel and changes in transportation and environmental policy in the US and the UK

This paper reviews recent research into the demand inducing effects of new transportation capacity. We begin with a discussion of the basic theoretical background and then review recent research both in the UK and the US. Results of this research show strong evidence that new transportation capacity induces increased travel, both due to short run effects and long run changes in land use development patterns. While this topic has long been debated amongst transportation planners, the fundamental hypothesis and theory has long been apparent in studies of transportation economics and planning that evaluated different issues (e.g. travel time budgets and urban economic development effects). We summarize much of this work and relate the theoretical issues to recent empirical research. We then proceed to examine recent changes in transportation and environmental policy in the US and the UK. The role of the new knowledge of induced travel effects would be expected to lead to changes in the conduct of transportation and environmental policy. Changes in policy and implementation of those policies are still occurring and we provide some suggestions on how to move forward in these areas.     

Zambia,the TAZARA and the alternative outlets to the sea

Zambia has attempted to reduce her excessive transport dependency on her traditional transport routes via South Africa and the former Portugese colonies. The costly construction of the Tanzania‐Zambia Railway (TAZARA) was part of this diversification strategy. This article examines the nature, extent and direction of Zambian traffic, including its historical evolution. It explores further the place of TAZARA among the various routes to Mozambican, Angolan and South African ports, and the ensuing actual and potential competition. Future traffic patterns will be influenced not only by the direct and service‐oriented costs of the different lines, but also by the region's volatile and uncertain political climate.