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1.
ABSTRACT

The need for improved public transport (PT) ticketing in ever-growing deregulated PT markets has made well-designed integrated ticketing systems a priority area of intervention for PT service providers around the world. Yet, very little practical evidence of its impacts are reported in Sweden and in the world at large. The focus of this study was the impacts of the Movingo integrated ticketing scheme in terms of PT patronage, user satisfaction and the perceived quality of the ticketing set-up. Three travel surveys were conducted along the Stockholm-Uppsala route. Methods including logistic regression and correlated t-tests were used to analyse the samples. The findings suggest that the scheme made rail commuting more attractive resulting in an overall increase of about 24% in ticket sales with 3% – 15% car commuters reporting that they patronised PT services after the project. The scheme also resulted in increased rail commuter satisfaction. The overall perceived quality of the ticketing set-up did not however improve due to interoperability challenges. Service providers’ uncertainty about equitable distribution of revenue among the participating service providers, interoperability challenges and the lack of interest among most of the participating service providers to sell Movingo tickets are some issues to be addressed.  相似文献   
2.
The Straits of Malacca and Singapore are an important trade route linking the Indian Ocean to the South China Sea and Pacific Ocean. They are also rich in resources and support a range of activities that benefit the economies of the littoral states (Indonesia, Malaysia and Singapore). This important shipping route is a very congested waterway and the authorities are keen to improve navigation facilities to promote ship safety and reduce the risk of groundings, collisions and accidents. This will also help to protect the marine environment from the effects of pollution and hence reduce its damaging impact on activities related to the Straits, e.g. fisheries and tourism. The Marine Electronic Highway (MEH) is an attempt to bring together maritime safety technologies and environmental management systems. The paper examines the costs of providing such a highway and considers some of the benefits which could accrue from its implementation. The analysis, conducted in the form of a cost-benefit study, clearly shows the economic viability of the scheme.  相似文献   
3.
The shipping industry in Nigeria since the early 1990s has been experiencing a continuous disastrous downturn. Nigerian shipping companies' participation in international shipping has continued to be very limited. Their presence and impact is hardly felt in the world's shipping industry. Both the national carriers (that is shipping companies with national carrier status) and other indigenous private shipping companies have vessel as well as management problems. These problems have led to the poor performance of the Nigerian shipping industry for over a decade now. The carriers in the industry are not attaining for the country the gains that are supposed to emanate from shipping. This paper points out the importance of shipping to a nation, identifies the problems the country's shipping companies are facing and proffers solutions that include merging of the companies to have strong financial standing and a competitive edge.  相似文献   
4.
Major highway reconstruction can cause significant disruptions to existing travel patterns and economic activity. Reducing these impacts on travelers, shippers, businesses and residents requires that innovative and effective transportation management actions be developed and implemented. This paper reports the major findings and recommendations of a research study on managing transportation during highway, reconstruction. The primary objectives of the study were
–  to investigate and document the critical interrelationships among state-of-the-art reconstruction and scheduling techniques, traffic accommodation strategies, construction quality control measures, and project planning and evaluation processes, and
–  to formulate and recommend a corridor transportation management process that can be used to develop, implement and evaluate a transportation management plan of strategies to mitigate the corridor-wide impacts of major highway reconstruction.
The recommended process consists of five chronological phases, each composed of many tasks having related focuses within the overall process. Each task is designed to contribute to the common objective of seeing that an effective transportation management plan for mitigating travel impacts throughout the project corridor is successfully realized. This process was formulated on the basis of information collected on 25 highway reconstruction projects throughout the United States by way of site visits, direct meetings with project personnel, requests for documentation, and phone interviews.  相似文献   
5.
This is the second of two background papers sponsored for the Symposium by the Administrative Commission for the north of the Netherlands. Its purpose is to provide an indication of the effects of the proposed high speed rail line between Amsterdam, Groningen and Hamburg on employment in the corridor. The authors first review the techniques of forecasting these effects discussed in the literature. The potentials approach is adopted for their analysis, the mathematics and underlying assumptions of which are presented. Finally, this model is run to provide an estimate of the impact on regional employment of three variants of the proposed rail line.  相似文献   
6.
7.
ABSTRACT

Predicting the risk of traffic demands and delays exceeding critical limits at road junctions, airports, hospitals, etc., requires knowing how both mean and variance of queue size vary over time. Microscopic simulation can explore variability but is computationally demanding and gives only sample results. A computationally efficient approximation to the mean is used in many modelling tools, but only empirical extensions for variance in particular situations have been available. The paper derives theoretical formulae for time-dependent and equilibrium variance, believed to be novel and to apply generally to queues covered by the Pollaczek–Khinchin mean formula, and offering possible structural insights. These are applied in an extended approximation giving mutually consistent mean and variance estimates with improved accuracy. Tests on oversaturated peak demand cases are compared with Markov probabilistic simulation, demonstrating accuracy (R2?>?0.99) for typical random, priority-like (M/M/1) and traffic-signal-like (M/D/1) queues. Implications for risk analysis, planning and policy are considered.  相似文献   
8.
Combining the present situation and development trend of different tunnel support technologies at home and abroad, this paper analyzes the problems of rockburst in hard rock tunnels and large deformation in soft rock tunnels caused by high ground stress. It is concluded that: 1) regarding the rockburst problem, the current support technology is mainly influenced by the rock burst mechanism which is dominated by static factors, and so the used support components are generally of smaller deformation performance and "passive support" properties; 2) as the rockburst is the result of dynamic-static stress coupling, and only the anchor bolt has the "active support" attribute in the current "shotcrete+anchor bolt+wire net" support system, so the best support system should have the two functions of active support and energy release in terms of the rockburst problem, and the key focus of the research and development is anchorage members; 3) there are three main support types for large deformation in soft rock tunnels, e.g. the heavy support, layered support and yielding support. Among them, the heavy support system in underground cavern with large deformation is easy to induce excessive surrounding rock pressure, and so the applicable conditions are limited. The layered support system is still not the best choice due to its immature theoretical study, difficult determination of the thickness value and the installation time of each support layer and the interference to construction progress. With the characteristics of timely support and yielding while supporting, the yielding support system can give full play to the performance values of surrounding rocks and supporting materials, and make both of them reach the optimal state, so it is the best choice for supporting the soft rock tunnels with large deformations. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   
9.
A new approach for improving the performance of freight train timetabling for single-track railways is proposed. Using the idea of a fixed-block signaling system, we develop a matrix representation to express the occupation of inter- and intra-station tracks by trains illustrating the train blocking time diagram in its entirety. Train departure times, dwell times, and unnecessary stopping are adjusted to reduce average train travel time and single train travel time. Conflicts between successive stations and within stations are identified and solved. A fuzzy logic system is further used to adjust the range of train departure times and checks are made to determine whether dwell times and time intervals can be adjusted for passenger and freight trains at congested stations to minimize train waiting times. By combining manual scheduling expertise with the fuzzy inference method, timetable efficiency is significantly improved and becomes more flexible.  相似文献   
10.
West  Jens  Börjesson  Maria 《Transportation》2020,47(1):145-174

This paper performs an ex-post cost–benefit and distribution analysis of the Gothenburg congestion charges introduced in 2013, based on observed effects and an ex-post evaluated transport model. Although Gothenburg is a small city with congestion limited to the highway junctions, the congestion charge scheme is socially beneficial, generating a net surplus of €20 million per year. From a financial perspective, the investment cost was repaid in slightly more than a year and, from a social surplus perspective, is repaid in < 4 years. Still, the sums that are redistributed in Gothenburg are substantially larger than the net benefit. In the distribution analysis we develop an alternative welfare rule, where the utility is translated to money by dividing the utility by the average marginal utility of money, thereby avoiding putting a higher weight on high-income people. The alternative welfare rule shows larger re-distribution effects, because paying charges is more painful for low-income classes due to the higher marginal utility of money. Low-income citizens pay a larger share of their income because all income classes are highly car dependent in Gothenburg and workers in the highest income class have considerably higher access to company cars for private trips. No correlation was found between voting pattern and gains, losses or net gain.

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