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381.
In January 2009, following a lengthy industry review and consultation process, the New Zealand Public Transport Management Act (PTMA) came into force. The Act allows Regional Transport Authorities, as the primary procurers of public transport services, to place either a control or a contracting requirement upon services that are registered as commercial requiring no subsidy. The imposition of either the control or the contracting requirement is designed to facilitate greater system integration, improve service continuity and enhance services to the customer, andallow the Authority to invest in key strategic projects, such as integrated fares and ticketing, so as to grow patronage.The PTMA’s other objective is to ensure improved value for public subsidies. Recent years have seen significant subsidy inflation for seemingly little commensurate benefits. The Act will allow the Regional Transport Authority to achieve greater value for money through improved farebox, a shift to longer, larger contracts to increase competition in the market, a more appropriate allocation of risk, and the removal of the ability of operators to ‘game’ the current system by using strategically placed commercial services as barriers to competition.Similar concerns have also stimulated new legislation in the UK and this paper illustrates the parallels in the environment and proposed response. 相似文献
382.
Lawrence J. Doctors Alexander H. Day David Clelland Philip Beveridge 《Journal of Marine Science and Technology》2010,15(4):345-358
A series of carefully controlled experiments on the wave-generation characteristics of a model of a compartmented surface-effect
ship has been conducted in a towing tank. Configurations of the model included cases encompassing one subcushion and two subcushions,
as well as differing values of the pressures in the subcushions. It was shown that a reduced wave generation in the appropriate
Froude number range could be achieved in this manner. Furthermore, a previously developed theory for the wave generation of
marine vessels was verified for the model for a Froude number greater than 0.40. 相似文献
383.
Does scale heterogeneity across individuals matter? An empirical assessment of alternative logit models 总被引:2,自引:0,他引:2
There is growing interest in establishing a mechanism to account for scale heterogeneity across individuals (essentially the
variance of a variance term or the standard deviation of utility over different choice situations), in addition to the more
commonly identified taste heterogeneity in mixed logit models. A number of authors have recently proposed a model that recognizes
the relationship between scale and taste heterogeneity, and investigated the behavioural implications of accounting for scale
heterogeneity in contrast to a term in the utility function, itself. In this paper we present a general model that extends
the mixed logit model to explicitly account for scale heterogeneity in the presence of preference heterogeneity, and compare
it with models that assume only scale heterogeneity (referred to as the scale heterogeneous multinomial logit model) and only
preference heterogeneity. Our empirical assessment suggests that accommodating scale heterogeneity in the absence of accounting
for preference heterogeneity may be of limited empirical interest, resulting in a statistically inferior model, despite it
being an improvement over the standard MNL model. Scale heterogeneity in the presence of preference heterogeneity does garner
favour, with the generalized mixed logit model an improvement over the standard mixed logit model. The evidence herein suggests,
however, that compared to a failure to account for preference heterogeneity that is consequential, failure to account for
scale heterogeneity may not be of such great empirical consequence in respect of behavioural outputs such as direct elasticities
and willingness to pay. However additional studies are required to establish the extent to which this evidence is transferable
to a body of studies. 相似文献
384.
Transportation - The benefits of cycling have been well established for several decades. It can improve public health and make cities more active and environmentally friendly. Due to the... 相似文献
385.
Transportation - Interest in modal preferences remains a topic of high interest as governments make infrastructure decisions that often favour one mode over the other. An informative input into the... 相似文献
386.
Transportation - The emerging technology of autonomous vehicles has been widely recognized as a promising urban mobility solution in the future. This paper considers the integration of autonomous... 相似文献
387.
Soonhung Han Yeon-Seung Lee Young Bok Choi 《Journal of Marine Science and Technology》2012,17(1):1-17
Hydrodynamic optimizations of ship hull forms have been carried out employing parametric curves generated by fairness-optimized B-Spline form parameter curves, labeled as F-Spline. Two functionalities of the parametric geometry models are used in the present study: a constrained transformation function to account for hull form variations and a geometric entity used in full parametric hull form design. The present F-Spline based optimization procedure is applied to two distinct hydrodynamic hull form optimizations: the global shape optimization of an ultra-large container ship and the forebody hull form for the hydrodynamic optimization of an LPG carrier. Improvements of ship performance achieved by the proposed F-Spline procedure are demonstrated through numerical experiments and through correlations with experimental data. The ultra-large containership was built and delivered to the ship owner. The present study validates the effectiveness of the proposed hydrodynamic optimization procedure, ushering in process automation and performance improvement in practical ship design practices. 相似文献
388.
Despite widespread growth in on-road public transport priority schemes, road management authorities have few tools to evaluate
the impacts of these schemes on all road users. This paper describes a methodology developed in Melbourne, Australia to assist
the road management authority, VicRoads, evaluate trade-offs in the use of its limited road-space for new bus and tram priority
projects. The approach employs traffic micro-simulation modelling to assess road-space re-allocation impacts, travel behaviour
modelling to assess changes in travel patterns and a social cost benefit framework to evaluate impacts. The evaluation considers
a comprehensive range of impacts including the environmental benefits of improved public transport services. Impacts on public
transport reliability improvements are also considered. Although improved bus and tram reliability is a major rationale for
traffic priority its use in previous evaluations is rare. The paper critiques previous approaches, describes the proposed
method and explores some of the results found in its application. A major finding is that despite a more comprehensive approach
to measuring the benefits of bus and tram priority, road-space reallocation is difficult to economically justify in road networks
where public transport usage is low and car usage high. Strategies involving the balanced deployment of bus and tram priority
measures where the allocation of time and space to PT minimises negative traffic impacts is shown to improve the overall management
of road-space. A discussion of the approach is also provided including suggestions for further methodology development.
相似文献
Bill YoungEmail: |
389.
Young H. Cho J. Kim Assistant Professor 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,25(1):51-69
A method to study handling characteristics of a vehicle moving along a curved path is presented. A simple bicycle model and a feedback controller with proportional gain are used to simulate the vehicle and the driver. The lateral stability of the vehicle/driver system is analyzed by using the root locus method and numerical integration in the time domain. The effect of the curvature on the system stability is discussed in detail. A new suggestion is made for the look ahead distance to calculate the preview lateral error of the vehicle with respect to the center of the road. Interesting results are shown for some important parameters such as the gain factor, the vehicle speed and the curvature of the path. Possible extensions of the method to more general cases and other applications are discussed. 相似文献
390.
David Briginshaw 《轨道交通》2007,(5):74-74
泰国曼谷市开始建设一条新线连接市中心和苏汪纳普机场,该工程总投资为250亿泰铢(6.75亿美元),预计2007年10月开通。 相似文献