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801.
Jan A. Van Der Linden 《Maritime Policy and Management》2001,28(1):33-54
Input-output analysis basically provides an estimation of a sector's economic impact by taking into account the indirect effects on all other sectors. For purposes of policy making, however, this may produce rather rigid and inaccurate results. This paper, therefore, introduces some extensions to the basic impact analysis. These extensions secure flexibility, completeness and accurateness of the outcomes. First, an accurate cost structure is determined in a bottom-up approach, i.e. by using data from a sample of representative companies. This allows for reliable outcomes and a flexible definition of sub-sectors. Secondly, the analysis is made in an intercountry context. Thirdly, the expenditure effects of generated income are determined by a macroeconomic module. Fourthly, company-level responses to alternative policy scenarios are investigated and translated into changing model parameters. These four basic elements are applied in a case study concerning the shipping sector of Germany. The scenarios are a continuation of the present policy, a laissez-faire policy, and two framework policies in which the government creates a favourable environment for shipping companies. For each scenario, the effects on value added, employment, tax revenues and expenditures are analysed and evaluated. This paper, thus, shows the relevance of accordingly amplified input-output analysis for policy purposes. 相似文献
802.
There has been a great deal of research on deriving estimates of the value of travel time savings (VTTS) as a way of converting
travel time benefits of toll roads relative to free routes into monetary units, the major user benefit in the development
of forecasts of traffic and hence revenue streams. By contrast there has been almost no consideration given to identifying
the role that various tollroad products play in establishing preferences for toll routes over non-tolled routes. Increasingly
tollroads give users the option to pay by cash at a toll booth, by electronic tolling or by a pre- or post-paid debit and
credit account system involving vehicle identification. The efficiency gained by electronic tolling for both the users and
the operator have resulted in moves in many jurisdictions to eliminate cash collection entirely (or not introduce it when
introducing a new tolled road facility), and to introduce a range of pre- and post-payment options. This has been accompanied
by a growing move to distance-based charging in some contexts which is more cumbersome to structure with a cash option. This
paper investigates current and potential travellers’ preferences for a range of toll products and how much individual’s are
willing to pay for very specific toll products. Data from a stated choice experiment is used in a mixed logit model to establish
the role that toll products play in the context of offered times and costs of alternative routes, in choosing between alternative
ways of paying for the use of tolled routes.
David A. Hensher is Professor of Management, and Founding Director of the Institute of Transport and Logistics Studies. David is a Fellow of the Academy of Social Sciences in Australia, Recipient of the 2006 Engineers Australia Transport Medal for lifelong contribution to transportation, member of Singapore Land Transport Authority International Advisory Panel (Chaired by Minister of Transport). David is on the editorial boards of 10 of the leading transport journals and Area Editor of Transport Reviews. David was appointed in 1999 by one of the worlds most prestigious academic publishing houses—Elsevier Science press as series and volume editor of a new handbook series “Handbooks in Transport”. Appointments over recent years include: a member of the executive committee that reviewed bus transport bids for the Olympic Games, the NSW Government’s Peer Review Committee for the Sydney Strategic Transport Plan, Peer reviewer for Transfund (NZ) of the New Zealand project evaluation program, Peer reviewer of the NZ Land Passenger Transport Procurement Strategy for Land Transport NZ, member of the executive committee of ATEC, a consortium promoting a freight rail system between Melbourne and Darwin; economic adviser to Gilbert+Tobin Lawyers on valuation methods in IP context; panel member of NSW Ministry of Transport benchmarking program; specialist toll road project adviser to Thiess. John M. Rose is Director of the Industry Program and a Deputy Director at Institute of Transport and Logistics Studies (ITLS). John’s research interests are in the areas of discrete choice modelling and efficient stated choice experiments. John has several articles published in the top Transportation and Logistics journals (including Transportation, Transportation Research A, B and E) and is a co-author of (with Professors David Hensher and William Greene) Applied Choice Analysis; A Primer, (2005) by Cambridge University Press. He is currently writing a book on generating efficient stated choice experimental designs (with Mike Bliemer, Delft). 相似文献
John M. RoseEmail: |
David A. Hensher is Professor of Management, and Founding Director of the Institute of Transport and Logistics Studies. David is a Fellow of the Academy of Social Sciences in Australia, Recipient of the 2006 Engineers Australia Transport Medal for lifelong contribution to transportation, member of Singapore Land Transport Authority International Advisory Panel (Chaired by Minister of Transport). David is on the editorial boards of 10 of the leading transport journals and Area Editor of Transport Reviews. David was appointed in 1999 by one of the worlds most prestigious academic publishing houses—Elsevier Science press as series and volume editor of a new handbook series “Handbooks in Transport”. Appointments over recent years include: a member of the executive committee that reviewed bus transport bids for the Olympic Games, the NSW Government’s Peer Review Committee for the Sydney Strategic Transport Plan, Peer reviewer for Transfund (NZ) of the New Zealand project evaluation program, Peer reviewer of the NZ Land Passenger Transport Procurement Strategy for Land Transport NZ, member of the executive committee of ATEC, a consortium promoting a freight rail system between Melbourne and Darwin; economic adviser to Gilbert+Tobin Lawyers on valuation methods in IP context; panel member of NSW Ministry of Transport benchmarking program; specialist toll road project adviser to Thiess. John M. Rose is Director of the Industry Program and a Deputy Director at Institute of Transport and Logistics Studies (ITLS). John’s research interests are in the areas of discrete choice modelling and efficient stated choice experiments. John has several articles published in the top Transportation and Logistics journals (including Transportation, Transportation Research A, B and E) and is a co-author of (with Professors David Hensher and William Greene) Applied Choice Analysis; A Primer, (2005) by Cambridge University Press. He is currently writing a book on generating efficient stated choice experimental designs (with Mike Bliemer, Delft). 相似文献
803.
Daniel A. Rodríguez Elizabeth M. Brisson Nicols Estupin 《Transportation Research Part D: Transport and Environment》2009,14(7):470-478
Few studies have examined the relationship between micro-scale features of the built environment and street segment usage. Micro-scale features of the built environment include the width of the sidewalk, the presence of amenities such as benches and trash bins, and the presence of crossing aids such as stoplights and crosswalks. This study employs segment-level primary data collected for 338 street segments in close proximity to one of 71 bus rapid transit stations in Bogotá, Colombia. We also use secondary data to control for area-level characteristics such as density, socio-economic stratum, unemployment, and crime. Factor and regression analyses are to use identify two dimensions of the built environment that are associated with higher levels of pedestrian activity: pedestrian-friendly amenities, comprised of wider and higher quality sidewalks and the presence of amenities such as benches, garbage cans, and bike paths; and connectivity, comprised of higher levels of road density, three- and four-way intersections, and density. In addition, we find greater pedestrian activity on segments with higher development intensity, with more mix of land uses, and with more crossing aids. Although the relationships identified are not causal, they are suggestive in terms of planning successful built environment interventions. 相似文献
804.
2007年6月13日,巴拿马运河管理局在上海浦东香格里拉大酒店举办“巴拿马海运日”,巴拿马运河管理局国际顾问委员会主席、国际海事组织(IMO)前秘书长威廉·A·奥尼尔先生在开幕仪式上发表了演讲。奥尼尔先生的讲话着重强调海运在当代经济和社会发展中不可替代的巨大作用,集装箱化又是影响最大的因素之一,而且在可持续发展大趋势下,海运又是能效最高、对生态环境最友好的运输方式。演讲还指出海运事业广泛的国际性以及各国政府在政策法规等方面合作和协调对发展全球海运业的重要意义。奥尼尔先生高度赞扬巴拿马运河回归后的出色管理,以及运河在21世纪,尤其是在扩建计划完成后,对世界航运业的重大贡献。应本刊之约,讲演稿由作者修改后发表如下。 相似文献
805.
Hybridation of generation propagation models and SPH model to study severe sea states in Galician Coast 总被引:1,自引:0,他引:1
A.J.C. Crespo M. Gmez-Gesteira P. Carracedo R.A. Dalrymple 《Journal of Marine Systems》2008,72(1-4):135
The Atlantic and Cantabrian coasts of the Iberian Peninsula suffer the periodic passage of storms which give rise to severe sea states. Standard generation- propagation models (WAM, WAVEWATCH, SWAN) are commonly used for operational oceanography purposes with satisfactory results both in the open ocean and in near shore areas but they do not provide information about the possibility of flooding in coastal areas. A 2D HV version of SPH (Smoothed Particle Hydrodynamics) model is considered to propagate the signal provided by generation- propagation models to the coast and to analyze the nature of coastal structures overtopping as a tool to create maps of risk. SPH is shown to provide valuable information about overtopping (maximum water height and water velocity) under the stormy conditions suffered by the Galician coast on February 17, 2006. 相似文献
806.
T. Fang R. E. Coverdill C. -F. F. Lee R. A. White 《International Journal of Automotive Technology》2008,9(5):551-561
An optically accessible single-cylinder high speed direct-injection (HSDI) Diesel engine equipped with a Bosch common rail
injection system was used to study low temperature Modulated Kinetics (MK) combustion with a retarded single main injection.
High-speed liquid fuel Mie-scattering was employed to investigate the liquid distribution and evolution. By carefully setting
up the optics, three-dimensional images of fuel spray were obtained from both the bottom of the piston and the side window.
The NOx emissions were measured in the exhaust pipe. The influence of injection pressure and injection timing on liquid fuel
evolution and combustion characteristics was studied under similar fuel quantities. Interesting spray development was seen
from the side window images. Liquid impingement was found for all of the cases due to the small diameter of the piston bowl.
The liquid fuel tip hits the bowl wall obliquely and spreads as a wall jet in the radial direction of the spray. Due to the
bowl geometry, the fuel film moves back into the central part of the bowl, which enhances the air-fuel mixing process and
prepares a more homogeneous air-fuel mixture. Stronger impingement was seen for high injection pressures. Injection timing
had little effect on fuel impingement. No liquid fuel was seen before ignition, indicating premixed combustion for all the
cases. High-speed combustion video was taken using the same frame rate. Ignition was seen to occur on or near the bowl wall
in the vicinity of the spray tip, with the ignition delay being noticeably longer for lower injection pressure and later injection
timing. The majority of the flame was confined to the bowl region throughout the combustion event. A more homogeneous and
weaker flame was observed for higher injection pressures and later injection timing. The combustion structure also proves
the mixing enhancement effect of the liquid fuel impingement. The results show that ultra-low sooting combustion is feasible
in an HSDI diesel engine with a higher injection pressure, a higher EGR rate, or later injection timing, with little penalty
on power output. It was also found that injection timing has more influence on HCCI-like combustion using a single main injection
than the other two factors studied. Compared with the base cases, simultaneous reductions of soot and NOx were obtained by
increasing EGR rate and retarding injection timing. By increasing injection pressure, NOx emissions were increased due to
leaner and faster combustion with better air-fuel mixing. However, smoke emissions were significantly reduced with increased
injection pressure. 相似文献
807.
Transportation - Major cities in developing countries are increasingly becoming motorized. Thus, effective solutions to address the negative impacts that come with rising car-ownership are needed... 相似文献
808.
Hyun Woong Cho Bhargava R. Chilukuri Jorge A. Laval Angshuman Guin Wonho Suh 《运输规划与技术》2020,43(5):475-487
ABSTRACT This paper presents a case study of the optimal ALINEA ramp metering system model of a corridor of the metro Atlanta freeway. Based on real-world traffic data, this study estimates the origin-destination matrix for the corridor. Using a stochastic simulation-based optimization framework that combines a micro-simulation model and a genetic algorithm-based optimization module, we determine the optimal parameter values of a combined ALINEA ramp metering system with a queue flush system that minimizes total vehicle travel time. We found that the performance of ramp metering with optimized parameters, which is very sensitive possibly because bottlenecks are correlated, outperforms the no control model with its optimized parameters in terms of reducing total travel time. 相似文献
809.
Freight transport demand is a demand derived from all the activities needed to move goods between locations of production to locations of consumption, including trade, logistics and transportation. A good representation of logistics in freight transport demand models allows us to predict the effects of changes in logistics systems on future transport flows. As such it provides better estimations of the costs of interaction and allows to predict changes in spatial patterns of freight transport flows more accurately. In recent years, the attention for freight modelling has been growing and new research work has appeared aimed at incorporating logistics in freight models. In this paper we review the state of the art in the representation of logistics considerations in freight transport demand models. Our focus is on the service and cost drivers of changes in logistics networks and how these affect freight transport. Our review proceeds along a conceptual framework for modelling that goes beyond the conventional 4-step modelling approach. We identify promising areas for freight modelling that have an integrative function within this framework, such as spatial computable general equilibrium models, supply chain choice models and hypernetwork models. 相似文献
810.
The demand for inland freight transport in Europe is mainly met by road transport, leading to unsustainable impacts such as air pollution, greenhouse gas emissions and congestion. Since rail transport has lower externalities than road transport, a modal shift from road to rail is an accepted policy goal for achieving a more sustainable and competitive transport system. However, intermodal road–rail transport is mainly competitive for long-distance transport, and as a consequence, the potential for modal shift is limited. The cost efficiency of road–rail intermodal transport is particularly sensitive to pre- and post-haulage (PPH) costs, since this activity typically has a larger cost compared with its share of the total distance in the transport chain. For intermodal transportation over shorter distances, for example, below 300 km and where there are substantial PPH activities at both ends of the chain, the competitiveness of the intermodal transport system compared with that of direct road is low. Improving the efficiency of PPH activities is, therefore, of utmost importance for the competitiveness of the intermodal transport system. This paper looks into the issue of improving the cost efficiency of an intermodal transport chain by implementing an innovative and flexible legal framework regarding the PPH activities in the chain. By extending the legal framework with exemptions for longer vehicles in PPH, the cost efficiency could be greatly improved. The purpose of such a framework is to allow and enable, for PPH exclusively, the use of 2?×?40 foot or even two semi-trailers using only one vehicle in the context of the Swedish regulatory framework. This paper develops a strategic calculation model for assessing and investigating the consequences of such a framework and investigates the framework's potential in terms of cost efficiency. The model in combination with a sensitivity analysis of input variables gives a comprehensive understanding of the effects of PPH under different circumstances. From the results, it is evident that there are substantial positive effects associated with a PPH framework of longer vehicles. Results indicate that a typical shipper may experience cost reductions of about 5–10% of the total costs of the intermodal transport chain. In summary, a more innovative and flexible legal framework regarding vehicle length in the PPH links can contribute to a greater modal shift, improved cost efficiency and more environmentally friendly transportation systems. 相似文献