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101.
Toshiyuki Yamamoto 《Transportation》2009,36(3):351-366
The interactions among different types of vehicle ownership including car, motorcycle and bicycle are examined by developing
simultaneous vehicle ownership models in this study. Large scale person trip survey data for Osaka metropolitan area, Japan
and Kuala Lumpur, Malaysia are used for empirical analysis. The results suggest that population density at residential area
significantly and negatively affects car ownership for both areas, and that the effects are larger for Osaka metropolitan
area than for Kuala Lumpur. Also, bicycle ownership becomes higher at higher population density area for Osaka area, while
higher at lower population density area for Kuala Lumpur, which represents the different usage patterns of bicycle between
the two areas.
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Toshiyuki YamamotoEmail: |
102.
When a new public transport service is introduced it would be valuable for public authorities, financing organisations and
transport operators to know how long it will take for people to start to use the service and what factors influence this.
This paper presents results from research analysing the time taken for residents living close to a new guided bus service
to start to use (or adopt) the service. Data was obtained from a sample of residents on whether they used the new service
and the number of weeks after the service was introduced before they first used it. Duration modelling has been used to analyse
how the likelihood of starting to use the new service changes over time (after the introduction of the service) and to examine
what factors influence this. It is found that residents who have not used the new service are increasingly unlikely to use
it as time passes. Those residents gaining greater accessibility benefits from the new service are found to be quicker to
use the service, although the size of this effect is modest compared to that of other between-resident differences. Allowance
for the possibility that there existed a proportion of the sample that would never use the new service was tested using a
split population model (SPD) model. The SPD model indicates that 36% of residents will never use the new service and is informative
in differentiating factors that influence whether Route 20 is used and when it is used.
Kiron Chatterjee has been a Senior Lecturer at the University of the West of England, Bristol, since 2003 and previously was at the University of Southampton. Currently, a main focus of his research is on longitudinal analysis of travel behaviour to improve policy analysis. Kang-Rae Ma received a PhD in Planning from University College London. He worked at the University of the West of England, Bristol, and the Korea Transport Institute before he joined Chung-Ang University as an Assistant Professor. His research interests include modelling of travel behaviour and urban excess commuting. 相似文献
Kang-Rae MaEmail: |
Kiron Chatterjee has been a Senior Lecturer at the University of the West of England, Bristol, since 2003 and previously was at the University of Southampton. Currently, a main focus of his research is on longitudinal analysis of travel behaviour to improve policy analysis. Kang-Rae Ma received a PhD in Planning from University College London. He worked at the University of the West of England, Bristol, and the Korea Transport Institute before he joined Chung-Ang University as an Assistant Professor. His research interests include modelling of travel behaviour and urban excess commuting. 相似文献
103.
This paper looks at the first and second best jointly optimal toll and road capacity investment problems from both policy
and technical oriented perspectives. On the technical side, the paper investigates the applicability of the constraint cutting
algorithm for solving the second best problem under elastic demand which is formulated as a bilevel programming problem. The
approach is shown to perform well despite several problems encountered by our previous work in Shepherd and Sumalee (Netw.
Spat. Econ., 4(2): 161–179, 2004). The paper then applies the algorithm to a small sized network to investigate the policy implications of the first and second
best cases. This policy analysis demonstrates that the joint first best structure is to invest in the most direct routes while
reducing capacities elsewhere. Whilst unrealistic this acts as a useful benchmark. The results also show that certain second
best policies can achieve a high proportion of the first best benefits while in general generating a revenue surplus. We also
show that unless costs of capacity are known to be low then second best tolls will be affected and so should be analysed in
conjunction with investments in the network.
Andrew Koh Prior to joining the Institute for Transport Studies in December 2005, Andrew was employed for number of years as a consultant in highway assignment modelling. He is an economist with wide ranging research interests in transport economics as well as evolutionary computation heuristics such as genetic algorithms, particle swarm optimisation and differential evolution. Simon Shepherd At the Institute for Transport Studies since 1989, he gained his doctorate in 1994 applying state-space methods to the problem of traffic responsive signal control in over-saturated conditions. His expertise lies in modelling and policy optimisation ranging from detailed simulation models through assignment to strategic land use transport models. Recently he has focussed on optimisation of road user charging schemes and is currently working on optimal cordon design and system dynamics approaches to strategic modelling. Agachai Sumalee Agachai is currently an Assistant Professor at Department of Civil and Structural Engineering, Hong Kong Polytechnic University (). He obtained a Ph.D degree with the thesis entitled “Optimal Road Pricing Scheme Design” at Leeds University in 2004. His research areas cover transport network modeling and optimization, stochastic network modeling, network reliability analysis, and road pricing. Agachai is currently an associate editor of Networks and Spatial Economics. 相似文献
Agachai SumaleeEmail: |
Andrew Koh Prior to joining the Institute for Transport Studies in December 2005, Andrew was employed for number of years as a consultant in highway assignment modelling. He is an economist with wide ranging research interests in transport economics as well as evolutionary computation heuristics such as genetic algorithms, particle swarm optimisation and differential evolution. Simon Shepherd At the Institute for Transport Studies since 1989, he gained his doctorate in 1994 applying state-space methods to the problem of traffic responsive signal control in over-saturated conditions. His expertise lies in modelling and policy optimisation ranging from detailed simulation models through assignment to strategic land use transport models. Recently he has focussed on optimisation of road user charging schemes and is currently working on optimal cordon design and system dynamics approaches to strategic modelling. Agachai Sumalee Agachai is currently an Assistant Professor at Department of Civil and Structural Engineering, Hong Kong Polytechnic University (). He obtained a Ph.D degree with the thesis entitled “Optimal Road Pricing Scheme Design” at Leeds University in 2004. His research areas cover transport network modeling and optimization, stochastic network modeling, network reliability analysis, and road pricing. Agachai is currently an associate editor of Networks and Spatial Economics. 相似文献
104.
Dongjoo Park Laurence R. Rilett Byron J. Gajewski Clifford H. Spiegelman Changho Choi 《Transportation》2009,36(1):77-95
With the recent increase in the deployment of ITS technologies in urban areas throughout the world, traffic management centers
have the ability to obtain and archive large amounts of data on the traffic system. These data can be used to estimate current
conditions and predict future conditions on the roadway network. A general solution methodology for identifying the optimal
aggregation interval sizes for four scenarios is proposed in this article: (1) link travel time estimation, (2) corridor/route
travel time estimation, (3) link travel time forecasting, and (4) corridor/route travel time forecasting. The methodology
explicitly considers traffic dynamics and frequency of observations. A formulation based on mean square error (MSE) is developed
for each of the scenarios and interpreted from a traffic flow perspective. The methodology for estimating the optimal aggregation
size is based on (1) the tradeoff between the estimated mean square error of prediction and the variance of the predictor,
(2) the differences between estimation and forecasting, and (3) the direct consideration of the correlation between link travel
time for corridor/route estimation and forecasting. The proposed methods are demonstrated using travel time data from Houston,
Texas, that were collected as part of the automatic vehicle identification (AVI) system of the Houston Transtar system. It
was found that the optimal aggregation size is a function of the application and traffic condition.
相似文献
Changho ChoiEmail: |
105.
In Brazil, the explosion of informal transport activity during the past decade has had profound effects on formal public transport
systems and is a source of great controversy in the urban transportation sector. A variety of policies have been proposed
to manage the growth of the sector. This study seeks to understand how proposed policies will impact the users of these systems.
A corridor in Rio de Janeiro with substantial informal activity was used as a case study. Measures of welfare changes in a
discrete choice framework were used to estimate proposed policies’ impacts on users. Eleven candidate policies were evaluated,
ranging from the eradication of the informal modes and investment in formal modes, to the legalization of the informal modes.
Benefits were compared with costs and the distribution of benefits across income classes was explored. Net benefits from some
policies were found to be substantial. Legalizing the informal sector was found to benefit users slightly but further investments
in the sector are probably inefficient. Users benefited most from improvements in formal mass transit modes, at roughly 100–200
dollars per commuter per year. Finally, policies to foster a competitive environment for the delivery of both informal and
formal services were shown to benefit users about 100 dollars per commuter per year. Together, the regulation of the informal
sector and investments in the formal sector serve to reinforce the movement towards competitive concessions for services and
help reduce the impacts of cartelization and costly in-road competition.
相似文献
Ronaldo BalassianoEmail: |
106.
Lidia P. Kostyniuk 《Transportation》2009,36(6):641-642
107.
This paper studies the fault diagnosis of singular stochastic systems. The probability distribution of output is measured
by probability density functions (PDFs), which are modeled by a square root B-spline expansion. An adaptive nonlinear observer
is proposed to estimate the size of the fault occurring in systems. Furthermore, the linear matrix inequality (LMI) approach
is applied to establish sufficient conditions for the existence of the observer. Finally, the simulation results are given
to indicate the method for diagnosing the fault. 相似文献
108.
Michael Ekow Manuel 《WMU Journal of Maritime Affairs》2017,16(3):473-483
Traditional seafarer training has always focused on the acquisition and use of practical skills. The prevailing view is that, while this approach addresses a degree of cognitive skills, it focuses on and gives much more emphasis to the acquisition of hands-on practical skills for the performance of specific tasks. On the other hand, academic education has been seen to be much more focused on the development of in-depth analytical and critical thinking skills; cognitive skills that are less reliant on hands-on task-oriented training, but stress critical reading and discussion. The global trend in maritime education and training is increasingly to link an essentially vocational education that provides specific and restricted competence outcomes with more general or deeper academic components leading to an academic qualification. This trend has led to some dilemmas for curriculum development, for training legislation in a global industry, and for achieving desired learning outcomes in a professional setting (in the shipping industry). This paper discusses some of the challenges arising from this trend and the opportunities the trend offers. 相似文献
109.
Carlos Jerome Lawrence A. Howard Ezgi Uzel Jameela R. Androulidakis 《WMU Journal of Maritime Affairs》2017,16(1):89-98
Protection against on-ship infectious disease—whether due to mishap or to harmful purpose—faces special situational problems. Sometimes, when infection levels on board have reached threshold levels, emergency actions are required. Often, the most thorough strategies for responding to threat are not feasible. A rapid first-stage test (RFT) is a fast, minimally invasive procedure used to rule out from possible infection a large percentage of an infection-threatened group. Prevention and control of on-ship infection need to combine various interconnected tactics. When timely criterion tests are not possible, the medical team must adopt fast alternative measures. The methods used to summarize protection against on-ship infectious agents included a scientific literature review and a web search. The fields of the review were maritime, health, and technology sources. Special attention was paid to material dealing with risks and threats of on-ship penetration by infectious agents, on-ship infection prevalence thresholds, and rapid diagnostic screens. The Bayes rule and the law of large numbers were applied to the analysis, for large on-ship populations, of RFT indications of crossing of an infection prevalence threshold. The increasing risk of serious on-ship infection—either accidental or purposeful—calls for a multi-layered protection approach. RFTs are a key part of the outer layer of such a defense. Well-designed and well-administered RFTs provide several advantages for defense against on-ship infection: low-cost, non-invasive, fast, and focuses on a drastically smaller number of infection possibilities. 相似文献
110.
The brittleness analysis and important nodes detection have been a hot spot in the complex networks. How to get the overall feature of the whole network and how to find out some important nodes are requisites to solve these problems. In this paper, we adopt the trace of the adjacency matrix and the centrality of the complex networks to give a quantitative and qualitative analysis of networks being studied. Results show that the k-shell plays a more important role than the degree centrality and the betweenness in finding important nodes, and it can also be used to give direction on the immunization and maintenance of complex networks. 相似文献