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41.
While equity has been an important consideration for transportation planning agencies in the U.S. following the passage of Civil Rights Act of 1964 (Title VI specifically) and the subsequent Department of Transportation directives, there is little guidance on how to assess the distribution of benefits generated by transport investment programs. As a result, the distribution of these benefits has received relatively little attention in transportation planning, compared to transport-related burdens. Drawing on philosophies of social justice, we present an equity assessment of the distribution of accessibility in order to define the rate of “access poverty” among the population. We then apply this analysis to regional transportation plan scenarios from the San Francisco Bay Area, focusing on measures of differences between public transit and automobile access. The analysis shows that virtually all neighborhoods suffer from substantial gaps between car and public transport-based accessibility, but that the two proposed transportation investment programs reduce access poverty compared to the “no project” scenario. We also investigate how access and access poverty rates vary by demographic groups and map low-income communities within access impoverished areas, which could be the subject of further focused investments.  相似文献   
42.
Recently, Chinese carriers entered the Australia–Europe route, a market currently served by several established airlines. The paper aims to explore and identify the contextual factors affecting the choice of China-based carriers for long-haul travel. The paper's innovation is in the way it uses the online comments made by readers of an aviation news article. In doing so, the paper highlights the advantages and limitations of such a data source and the full range of positive and negative perceptions about Chinese airlines as recorded by potential and actual travelers. This study highlights that in order to understand flight choice, it is worthwhile to consider the conventional itinerary choice factors in the context of the socio-cultural and historical influences. For researchers, the paper provides some evidence that air travelers apply compensatory decision rule in making airline choices. This supports the validity of the assumption of random-utility based choice models used in the study of air travel behavior.  相似文献   
43.
文中探讨如何运用SWOT战略分析方法确定乌海地区铁路运输业目前面临的重要外部机会和威胁,以及内部存在的主要优势和劣势,并运用SWOT定量分析模型,对乌海铁路运输业发展做出科学评估,在此基础上明确乌海铁路货运发展战略定位,研究并提出相应的发展策略,从而充分发挥该市的自身优势。  相似文献   
44.
Neighborhood social effects have recently become a focus of interest in transportation research, whereby transportation mode choice is not only affected by an individual’s characteristics and transportation system conditions, but also by the mode choices of that individual’s social neighbors. This study supports the neighborhood social effects argument, using a spatial econometrics approach and data from The Ohio State University (OSU) 2012 Campus Transportation Survey. A spatial probit model of commuters’ mode choices (bicycling versus non-bicycling) is estimated, accounting for spatial autocorrelation. The results show that the more OSU-affiliated bicycle riders are residing around an individual OSU commuter, the more attractive bicycling becomes, controlling for other factors such as gender, status, proximity to campus, bicycle infrastructure and attitudes. The results indicate that students and males are more likely to commute by bicycles. The probability of choosing bicycles decreases with distance from campus. In addition, proximity to bicycle infrastructure and physical environment both encourage respondents to bicycle. Feeling of safety, travel cost and concern for the environment also affect bicycling choice.  相似文献   
45.
针对目前构架加工工装缺乏通用性以及人工夹紧带来的夹紧力不均衡等问题,研制出适用于构架加工通用的液压自动夹紧工装,介绍了该工装的整体结构设计、工作原理和具体应用,该工装可应用于公司所有类型转向架构架的加工,同时具有装夹过程简单、夹紧力稳定等优点,具有较高的应用和推广价值。  相似文献   
46.
苏箭 《价值工程》2015,(5):97-98
随着校园周边交通条件的复杂化,中南大学校园周边出现了如交通拥堵、事故频发、环境污染等一系列交通问题,亟待提出有针对性的交通优化策略改善交通条件。本论文在借鉴和总结国内外大学校园交通组织的基础上,以中南大学麓山南路周边校区为研究对象,提出具体的交通优化策略。  相似文献   
47.
Putting climate change policy-integration into practice is challenged by problems of institutional misfit, due to, inter alia, deficient vertical administrative interplay. While most focus within the field of climate change research has targeted the national–local interplay, less is known about the interface of regional and local perspectives. Here, the aim is to study that interface with a specific focus on the relation between regional and local spatial planning actors, through a case-study of transport and coastal zone management in a Swedish municipality. The article is based on interviews (focus group and single in-depth) and official planning documents. The material reveals a tricky planning situation, replete with conflict. In practice, various institutional frameworks, claims and ambitions collide. The attempts to steer the local spatial planning initiatives from the regional level led to conflicts, which in turn seems to have hampered the overall work for climate change management through spatial planning. Furthermore, there are few traces of prospects of a smooth vertical institutional interplay able to support the overall aims related to integrating climate change mitigation and adaptation in spatial planning.  相似文献   
48.
Do the determinants of service and pricing on “regional” routes – linking towns and smaller cities to main trunk routes and/or to each other – differ from the established results from the literature? We study all flights (about 3000) on all regional routes (about 250) with scheduled airline service from one of about 130 regional towns or cities, in regional airline markets in six countries: Australia, Canada, New Zealand, Norway, Sweden, and a sample of three U.S. states which closely resemble the other regions studied. For each flight we have observations on up to five prices offered at different times before flight date. We also have equipment type and social-economic data. Overall, our results give qualified support to the standard gravity model of the extent of service between city pairs, though with two interesting differences: operators on regional routes have greater flexibility in the size of aircraft they can deploy, which results in a finer-grained variability of service offerings and, the presence of competition on regional routes has a large effect on the total supply of seats. We are able to successfully estimate a well-specified airfare model, which shows strong effects of competition on prices, quite substantial intertemporal price discrimination, and interesting differences between regional and main trunk route pricing.  相似文献   
49.
Due to the shortage of cargo aircraft, Chinese express companies have to provide transportation services with a hybrid method that consists of “rented bellies and self-owned cargo aircraft”. Because the bellies are rented from air passenger companies and because the cargo aircraft are owned by the express companies, it is important for the express companies to use their cargo aircraft as effectively as possible. This paper constructs a bi-level model to optimize the flight transportation network of an express company. The upper model designs the network and allocates the transportation capacity with the objective of minimizing the total transportation cost, and the lower model calculates the link flows in user equilibrium. Data from ShunFeng (SF) Express Company (China) are used to conduct the case study. Using the model outputs, the flows on links and at nodes are analyzed to illustrate the transportation and transshipment situations.  相似文献   
50.
This study presents a mathematical model that designs a reliable multi-modal transportation network for a biofuel supply chain system, where intermodal hubs are subject to site-dependent probabilistic disruptions. The disruption probabilities of intermodal hubs are estimated by using a probabilistic model which is developed using real world data. We developed an accelerated Benders decomposition algorithm to solve this challenging NP-hard problem. Numerical analysis show that the model selects to use intermodal hubs located in areas with low disruption probabilities. In case of a disaster, the reliable solution results in 6.21% savings over the minimum cost solution.  相似文献   
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