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61.
John K. Stanley David A. Hensher 《Transportation Research Part A: Policy and Practice》2011,45(8):789-801
Building on a growing research foundation, transport policy makers have begun to associate the ability to be mobile with having a role in the facilitation of social inclusion. However, the further connection to well-being is not as well understood. This paper explores the association between a person’s travel patterns, their risk of social exclusion and self-assessed well-being. Key influences on social exclusion are discussed, with trip making emerging as a significant influence. Trip making is not a significant direct influence on well-being but does exercise an indirect influence through the impact on risk of social exclusion. The modelling process enables a value for additional trips to be estimated, the value being about four times the values derived from conventional generated traffic approaches. Similar high values are found in separate metropolitan and regional case studies, confirming the significance of the results. 相似文献
62.
63.
The public transport system of Karlsruhe, in particular its innovative services on jointly used heavy rail lines, has received substantial attention throughout the past 20 years. The discussion of the system and of its development has been rather limited in the past, mostly highlighting technical aspects. This paper provides an overview of the development, including the urban development, of the region and of the funding system. The ridership and financial development of the operator is documented in detail. Three case studies focus on the integration of the system development in the general political process of the region and demonstrate the limitations of the operator under its current ownership structures. 相似文献
64.
Environmental assessments are on the critical path for the development of land, infrastructure and transportation systems. These assessments are based on planning methods which, in turn, are subject to continuous enhancement. The substantial impacts of transportation on environment, society and economy strongly urge the incorporation of sustainability into transportation planning. Two major developments that enhance transportation sustainability are new fuels and vehicle power systems. Traditional planning ignores technology including the large differences among conventional, hybrid and alternative fuel vehicles and buses. The introduction of alternative fuel vehicles is likely to change the traditional transportation planning process because different characteristics need to be taken into account. In this study a sustainability framework is developed that enables assessment of transportation vehicle characteristics. Identified indicators are grouped in five sustainability dimensions (Environment, Technology, Energy, Economy and Users). Our methodology joins life cycle impacts and a set of quantified indicators to assess the sustainability performance of seven popular light-duty vehicles and two types of transit buses. Bus Rapid Transit receives the highest sustainability index and the pickup truck the lowest. Hybrid electric vehicles are found to have the highest sustainability index among all other passenger vehicles. A sensitivity analysis shows the proposed sustainability dimensions produce robust sustainability assessment for several weighting scenarios. The results are both technology and policy sensitive, thus useful for both short- and long-term planning. 相似文献
65.
An altimeter data assimilation scheme has been tested in the OCCAM (Ocean Circulation and Climate Advanced Modelling) global 1/4°, 36-level model using a twin experiment format. The Cooper and Haines displacement scheme is used. The method works well in most regions and depths. Currents and densities in the top 1000 m generally improve by over 50–70% after 5 months of sea level assimilation every 15 days. Below 1000 m, an error reduction of up to 50% is achieved. The errors remain low during a further 60-day run without assimilation. Diagnostics for the North Atlantic, the Tropical Pacific and the Antarctic Circumpolar Current are shown alongside the global averages.The main problems encountered were in weakly stratified regions of the Antarctic and Arctic seas. A scale selective filter is developed to avoid assimilating scales much larger than the local deformation radius, and this avoids the adverse assimilation effects in the southern oceans. A companion paper uses this scheme to assimilate TOPEX and ERS-1 altimeter maps. 相似文献
66.
67.
Christopher Yang David McCollum Ryan McCarthy Wayne Leighty 《Transportation Research Part D: Transport and Environment》2009,14(3):147-156
This paper investigates how California may reduce transportation greenhouse gas emissions 80% below 1990 levels by 2050 (i.e., 80in50). A Kaya framework that decomposes greenhouse gas emissions into the product of population, transport intensity, energy intensity, and carbon intensity is used to analyze emissions and mitigation options. Each transportation subsector, including light-duty, heavy-duty, aviation, rail, marine, agriculture, and off-road vehicles, is analyzed to identify specific mitigation options and understand its potential for reducing greenhouse gas emissions. Scenario analysis shows that, while California’s 2050 target is ambitious, it can be achieved in transport if a concerted effort is made to change travel behavior and the vehicles and fuels that provide mobility. While no individual ‘‘Silver Bullet” strategy exists that can achieve the goals, a portfolio approach that combines strategies could yield success. The 80in50 scenarios show the impacts of advanced vehicle and fuels technologies as well as the role of travel demand reduction, which can significantly reduce energy and resource requirements and the level of technology development needed to meet the target. 相似文献
68.
Ioannis K. Chatjigeorgiou Spyros A. Mavrakos 《Journal of Marine Science and Technology》2007,12(4):218-231
This work considers the second-order sum-frequency diffraction problem for a stationary truncated surface-piercing circular
cylinder in bichromatic waves. The solution method was based on a semianalytical formulation of the second-order sum-frequency
diffraction potential. The boundary conditions were properly satisfied by introducing the “locked” and the “free” wave components
of the nonlinear velocity potential. The method was validated by comparing the calculated results with numerical data previously
reported by other authors. Particular attention was paid to the second-order sum-frequency heave forces and the change in
the wave run-up configuration due to the existence of the lower fluid domain underneath the truncated cylinder. 相似文献
69.
Proshanto K. Mukherjee 《WMU Journal of Maritime Affairs》2007,6(2):147-166
Within the comprehensive body of law encompassed by the International Convention on Safety of Life at Sea, 1974 (SOLAS), there
are two regimes that are topical and outstanding in the current maritime milieu. These are the international safety management
and the international ship and port facility regimes, both characterized by two codes serving as the centre of gravity of
each, namely, the ISM Code and the ISPS Code, respectively. In this article the concept of the code as a legal instrument
is perused following which a critical legal analysis is carried out of the two above-mentioned Codes, including their backgrounds,
the evolutionary process culminating into the regimes and their interrelationships. Several anomalies and inadequacies in
the two regimes are identified but in the final analysis it is concluded that both instruments are salutary additions to the
body of convention law generated by the International Maritime Organization (IMO). They will undoubtedly influence the continuing
development of international law in the field of maritime safety and security. 相似文献
70.
The transport demand in most major cities around the world can only be met with a high‐quality public transport system. The requirements on bus, rail, underground and tram systems are manifold with reliability and efficiency as the key factors. The service operating hours and the size of the network are often extended in order to serve the needs better. Further, most metropolitan areas are trying to provide more incentives for citizens to leave the car at home and use the local transit systems instead. The reasons are well known. Not only does a public transport system only make economical sense if it is well used, but most urban areas with a high car‐dependency face at least three major problems; safety, congestion, and pollution (noise and air pollution, land separation, etc.). It is generally recognised that to decrease car usage and to increase public transport usage a stick & carrot approach is needed. The London congestion‐charging scheme is an example since all revenues collected by the scheme are put into the improvement of bus and underground services. 相似文献