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1.
GLUTAMATE-IMMUNOREACTIVENEURONSINMEDULLARYRAPHE-CEREBELLUMPATHWAYINTHEKITTEN(江赛男),(刘荣桓)JiangSainan;,SimonJ.Fung;LiuRonghuan;,...  相似文献   
2.
ABSTRACT

This paper describes the development of railway station choice models suitable for defining probabilistic station catchments. These catchments can then be incorporated into the aggregate demand models typically used to forecast demand for new rail stations. Revealed preference passenger survey data obtained from the Welsh and Scottish Governments was used for model calibration. Techniques were developed to identify trip origins and destinations from incomplete address information and to automatically validate reported trips. A bespoke trip planner was used to derive mode-specific station access variables and train leg measures. The results from a number of multinomial logit and random parameter (mixed) logit models are presented and their predictive performance assessed. The models were found to have substantially superior predictive accuracy compared to the base model (which assumes the nearest station has a probability of one), indicating that their incorporation into passenger demand forecasting methods has the potential to significantly improve model predictive performance.  相似文献   
3.
Abstract

Corals and coral communities provide substantial societal benefits by virtue of their recreational and esthetic appeal, the habitat provided for commercially harvested fish and shellfish, the structural foundation provided for productive coastal ecosystems, and the market value of harvested coral specimens. Coral resources are subject to adverse effects from pollution, dredging, specimen collecting, anchor damage, commercial fishing, overharvesting, and activities related to offshore petroleum development. Management programs which protect coral resources in the United States comprise a patchwork of separate federal and state programs. They attempt to adapt broad regulatory authorities for parks, fisheries, offshore mineral resources, and other subjects for the purpose of coral conservation. These programs embody species‐specific, area‐specific, and generic approaches to coral management. This paper traces the evolution of U.S. coral management programs and comments on their respective strengths and weaknesses. Alternative approaches for strengthening management systems could include new coordinating committees, legislation, memoranda of agreement between involved agencies, and others.  相似文献   
4.
Macroscopic fundamental diagrams (MFD) of traffic for some networks have been shown to have similar shape to those for single links. They have erroneously been used to help estimate the level of travel in congested networks. We argue that supply curves, which track vehicles in their passage through congested networks, are needed for this purpose, and that they differ from the performance curves generated from MFD. We use a microsimulation model, DRACULA and two networks, one synthesizing the network for Cambridge, England, and one of the city of York, England, to explore the nature of performance curves and supply curves under differing patterns of demand.We show that supply curves differ from performance curves once the onset of congestion is reached, and that the incorrect use of performance curves to estimate demand can thus seriously underestimate traffic levels, the costs of congestion, and the value of congestion relief measures. We also show that network aggregated supply curves are sensitive to the temporal distribution of demand and, potentially, to the spatial distribution of demand. The shape of the supply curve also differs between origin–destination movements within a given network.We argue that supply curves for higher levels of demand cannot be observed in normal traffic conditions, and specify ways in which they can be determined from microsimulation and, potentially, by extrapolating observed data. We discuss the implications of these findings for conventional modelling of network management policies, and for these policies themselves.  相似文献   
5.
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.
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   
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7.
A new wave of liberalisation of domestic airline competition is taking place in less developed nations, although the initial motivation in most cases is to supplement the capacity of the government's own airline. Liberalisation tends to begin with free market entry and a strong interest in privatisation while other regulatory controls are maintained. This position is untenable and policy makers in the less developed countries are having to learn quickly without the benefit of the detailed analyses that preceded liberalisation in the developed countries. This paper explores these problems and focuses on the lessons that policy makers in the less developed countries can draw from experiences elsewhere.  相似文献   
8.
This study examines the association between urban form and walking for transport in Brisbane, Australia based on both panel and cross-sectional data. Cross-sectional data are used to determine whether urban form was associated with walking for transport in 2011. Panel data are used to evaluate whether changes in the built environment altered walking behaviour between 2009 and 2011. Results from the cross-sectional data suggest that individuals are significantly more likely to be walkers if they live in an area with a well-connected street network and an accessible train station. The longitudinal analysis confirms these relationships; there also was however, a significant impact of travel attitudes and perceptions on walking behaviour. The findings suggest that the built environment continues to be an important factor to encourage walking; however, interventions are also required to change social norms in order to increase the receptiveness for and participation in walking.  相似文献   
9.
Bike Share: A Synthesis of the Literature   总被引:1,自引:0,他引:1  
This paper begins by providing an overview of bike share programs, followed by a critical examination of the growing body of literature on these programs. This synthesis of previous works, both peer-reviewed and gray, includes an identification of the current gaps in knowledge related to the impacts of bike sharing programs. This synthesis represents a critically needed evaluation of the current state of global bike share research, in order to better understand, and maximize the effectiveness of current and future programs. Several consistent themes have emerged within the growing body of research on bike share programs. Firstly, the importance bike share members place on convenience and value for money appears paramount in their motivation to sign up and use these programs. Secondly, and somewhat counter intuitively, scheme members are more likely to own and use private bicycles than nonmembers. Thirdly, users demonstrate a greater reluctance to wear helmets than private bicycle riders and helmets have acted as a deterrent in jurisdictions in which helmets are mandatory. Finally, and perhaps most importantly from a sustainable transport perspective, the majority of scheme users are substituting from sustainable modes of transport rather than the car.  相似文献   
10.
Abstract

This paper quantifies and evaluates, utilising a ‘bottom-up’ approach, the effect on CO2 emissions of a modal shift from short-haul air travel to high-speed rail (HSR), based on projected passenger movements, between Sydney and Melbourne, Australia during the period 2010–2030. To date, peer-reviewed studies assessing the CO2 emissions from these competing modes of high-speed transportation have been restricted principally to a cross-sectional assessment, with a Eurocentric bias. This present comparative study seeks to address a gap in the literature by assessing, longitudinally, the CO2 emissions associated with the proposed operation of HSR against the ‘business-as-usual’ air scenario between Sydney and Melbourne. Under the assumed 50/50 modal shift, and the Australian government's current renewable electricity target, an annual reduction in CO2 emissions of approximately 14% could be achieved when compared with a ‘business-as-usual’ air scenario. This percentage reduction represents a 62 kt reduction in base year, 2010, and a 114 kt reduction in the final year, 2030. In total, the overall reduction achieved by such a modal shift, under the assumed conditions, during the period 2010–2030, equates to approximately 1.87 Mt of CO2. Importantly, if the electrical energy supply for HSR operations was further ‘decarbonised’, then it follows that a greater emission reduction would be achieved.  相似文献   
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