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1.
This paper explores insights about marginal airport costs that can be gained by analysing labour inputs and their variability. Based on hourly cost and traffic data for the airport of Helsinki, a multivariate time series approach is used incorporating correlated error terms to account for random shocks such as delays. We found for most airport services a linear relationship between labour input and aircraft movements, except for producing passenger services for international departing flights where a cubic cost relationship was estimated. The findings are comparable with earlier studies for US airports.  相似文献   

2.
Short-term airport congestion due to service peaks causes transitory peaks in demand for customer services and ground-handling processes. Efforts to maximize flight-specific revenues have been mitigated by the recognition of the excessive burden to the service processes caused by these busy periods. The costs of peak periods for one mid-size European airline at its main airport are examined. The case company can cut the costs of ground-handling processes by 30% by applying slightly different timetabling principles. In fact, by adjusting only a few flights during the morning rush hour the company could save up to a million euros annually. These results show the importance of estimating the total economic effects of service peaks also to the authorities and the providers of airport services. In future research, the revenue impacts of despoking should be considered in addition to total process costs.  相似文献   

3.
We analyze market shares for each public transport mode in total public transport ridership for the multimodal public transportation system of Athens, Greece. This analysis provides useful information for making investment decisions concerning the public transport infrastructure and for allocating subsidies. Due to the non-stationary properties of the data, cointegration techniques are applied to investigate the long run equilibrium relationships. Error Correction Models are implemented to estimate short run dynamics as well as the speed of adjustment from the short to the long run. Results suggest that fare and GDP are the main determinants of the public transport mode shares both in the short and in the long run. Findings also indicate the role of total ridership fluctuations in explaining variations in public transport mode shares.  相似文献   

4.
Climate change is a global problem and across the world there are major difficulties being experienced in reducing carbon dioxide (CO2) emissions. The transport sector in particular is finding it difficult to reduce CO2 emissions. This paper reports on two studies carried out by the authors in London (UK) and Delhi (India). It considers the common objectives for transport CO2 reduction, but the very different contexts and baselines, potentials for change, and some possible synergies.Different packages of measures are selected and scenarios developed for each context which are consistent with contraction and convergence objectives. CO2 reduction potentials are modelled and quantified by package and scenario. London is considering deep reductions on current transport CO2 emission levels; Delhi is seeking to break the huge projected rise in transport CO2 emissions.The scale of policy intervention required to achieve these goals is huge and there is certainly little public discussion of the magnitude of the changes required. The paper argues for a ‘strategic conversation’ at the city level, using scenario analysis, to discuss the priorities for intervention in delivering low carbon transport futures. A greater focus is required in developing participatory approaches to decision making, alongside network investments, urban planning, low emission vehicles and wider initiatives. Aspirations towards equitable target emissions may assist in setting sufficiently demanding targets. Only then is a wider awareness and ownership of potential carbon efficient transport futures likely to take place.  相似文献   

5.
This paper investigates vacationers’ short-term responses to a sharp increase in transport costs. It aims to (1) acquire an understanding of the relative popularity of the different types of responses among vacationers and (2) explore whether there are distinct market segments of vacationers that respond differently to a sharp increase in transport costs. Data are obtained from a novel, tailor-made questionnaire which was done in the Netherlands in 2012. Results show that no single response is either very popular or unpopular. Furthermore, using latent class cluster analysis, four market segments (classes) of vacationers are identified that have markedly distinct response patterns. It was found that Age and Income explain class membership.  相似文献   

6.
This paper analyzes the possibility to save container fleet management costs in repositioning empty containers through the use of foldable containers. We model this entire empty container flow as an integer programming problem with different strategies in empty container flow itinerary. The model is used to carry out numerical experiments that optimize the empty container repositioning in the hinterland, where there are serious empty container repositioning problems caused by extremely imbalanced trades. The study finds that foldable containers can substantially save on repositioning costs compared to the use of standard containers.  相似文献   

7.
Accessibility, or the ease to participate in activities and obtain resources in a given environment, is crucial for evaluating transportation systems. Greater accessibility is often achieved by increasing individuals' potential mobility. However, potential mobility, if realized by motorized modes, can also generate negative environmental impacts such as fossil fuel consumption and greenhouse gas (GHG) emissions. While the negative environmental impacts of greater mobility are acknowledged, there has been a lack of research to validate those impacts using empirical data, especially considering variations in individuals' mobility levels. This paper presents a method for estimating the expected environmental costs of accessibility represented by a network-time prism (NTP). A NTP delimits all accessible locations within a network and the available time for an individual to present at each location given a scheduled trip origin and destination, a time budget and the maximum achievable speeds along network edges. Estimating the expected environmental costs of a NTP involves three steps: (1) semi-Markov techniques to simulate the probabilities to move along network edges at given times; (2) the speed profiles for reachable edges, and (3) a cost function that translates speeds into environmental impacts. We focus on air quality and employ the motor vehicle emission simulator MOVESLite to estimate the CO2 emissions at both the edge and prism levels. We calibrate and validate the methods for experimental NTPs defined within the Phoenix, AZ, USA road and highway network using vehicles instrumented with GPS-enabled onboard diagnostic devices (OBD). We demonstrate the effectiveness of our method through two scenarios and investigate the impact of changes in mobility levels on the expected CO2 emissions associated with the experimental NTPs.  相似文献   

8.
9.
《Transport Policy》2004,11(2):141-154
This paper presents estimates of environmental costs in a set of 36 European airline markets. Cost are calculated for noise, air pollution and accident risk using data on aircraft emissions, exposure-response parameters and economic valuation of environmental goods. The ‘medium value’ cost estimate is 0.0201ECU per passenger-km. This result suggests that environmental costs represent only a small fraction (2.5%) of the internal cost of aviation as measured by the average ticket price. Noise costs are the dominant environmental cost at some 75% of the cost total. The medium estimates are sensitive to changes in the various assumptions in the pathways: a low and high estimate are three times lower and five times higher, respectively, than the medium estimate. The study further suggests that there are environmental economies of scale in air transport and that Chapter 2 aircraft are about a factor four more environmentally costly than Chapter 3 aircraft.  相似文献   

10.
11.
Following the example of maritime transport, the relocation of fleets abroad – referred to as flagging out – has become an important cost reduction strategy for road freight transport companies. Particularly after the EU Eastern Enlargement in 2004, many Austrian road freight transport companies took advantage of both the freedom of services and the lower costs in New Member States. This paper shows the results of four waves of surveys of Austrian road hauliers, describing developments, attitudes, motives and impacts of the phenomenon. There is also a discussion about the significance of the problem, which was seldom referred to in the scientific literature.  相似文献   

12.
Accessibility metrics are gaining momentum in public transportation planning and policy-making. However, critical user experience issues such as crowding discomfort and travel time unreliability are still not considered in those accessibility indicators. This paper aims to apply a methodology to build spatiotemporal crowding data and estimate travel time variability in a congested public transport network to improve accessibility calculations. It relies on using multiple big data sources available in most transit systems such as smart card and automatic vehicle location (AVL) data. São Paulo, Brazil, is used as a case study to show the impact of crowding and travel time variability on accessibility to jobs. Our results evidence a population-weighted average reduction of 56.8% in accessibility to jobs in a regular workday morning peak due to crowding discomfort, as well as reductions of 6.2% due to travel time unreliability and 59.2% when both are combined. The findings of this study can be of invaluable help to public transport planners and policymakers, as they show the importance of including both aspects in accessibility indicators for better decision making. Despite some limitations due to data quality and consistency throughout the study period, the proposed approach offers a new way to leverage big data in public transport to enhance policy decisions.  相似文献   

13.
14.
The regular and robust collection of traffic data for the entire road network in a given country will usually require high-cost investment in traffic surveys and automated traffic counters. This paper provides an alternative and low-cost approach for estimating annual average daily traffic values (AADTs) and the associated transport emissions for all road segments in a country. This is achieved by parsing and processing commonly available information from existing geographical data, census data, traffic data and vehicle fleet data. Ceteris paribus, we find that our annual average daily traffic estimation based on a neural network performs better than traditional regression models, and that the outcomes of our aggregated bottom-up road segment emission estimations are close to the outcomes from top-down models based on total energy consumption in transport. The developed approach can serve as a means of reliably estimating and verifying national road transport emissions, as well as offering a robust means of spatially analysing road transport activity and emissions, so as to support spatial emission inventory compilations, compliance with international environmental agreements, transport simulation modelling and transport planning.  相似文献   

15.
The dominance of road for hinterland services could be challenged by using rail-road or waterway-road transport because of costs, congestion and growing environmental constraints. A common dynamic that is very favorable to the development of combined transport is shared among the actors of the transport chain but with different starting positions considering the ports of the Northern Range.But combined transport must still demonstrate that it can compete with road transport. Road transport and combined transport are not directly comparable because they do not offer the same physical transport service. The organizational patterns of road and combined transport are investigated. The example of hinterland services to and from the port of Le Havre to the Paris region is a particularly interesting case because of the very short distance. It is shown that the competitiveness of combined transport in terms of price varies greatly according to the way road transport it competes with is organized and that the commercial policy of combined transport operators plays a key role for explaining this competitiveness. Additional services such as additional dwelling times and specific custom advantages are paramount of importance to encourage the shift from road transport to combined transport.  相似文献   

16.
We study a competitive facility location problem with identical suppliers competing in multiple markets subject to distribution network congestion. We first analyze the solution of a symmetric competitive location game and discuss the firms’ facility location and equilibrium market supply decisions. Then, we utilize the model to provide analytical characterization of the effects of traffic congestion costs on equilibrium distribution flows. These analytical results permit qualitative characterization of how changes in congestion levels and costs affect equilibrium location and distribution decisions. The results of extensive numerical studies serve to further illustrate the effects of traffic congestion costs on location, market supply quantity, and distribution decisions.  相似文献   

17.
Like many other countries, the Netherlands is experiencing a sharp rise in the ageing population. As age increases, people’s mobility may decrease. However, older people have more leisure time compared to their younger (working) counterparts, and potentially spend more time on social activities. Therefore, this group can possibly increase social travel demand. However, to date, the travel demand for social activities of senior citizens has received only little attention. This paper studies trip-making for social purposes, with a special focus on the demographic ageing factors. Using social activity diary data, models are estimated to predict the number of social trips, the travel distance and mode of transport for social trips. The results indicate that the elderly of today seem to be as mobile as their younger counterparts with respect to the number of social trips. High education and involvement in clubs on average result in more social trips and full time work is found to result in fewer social trips. With regard to trip distance the results show that the average travel distance does not decrease as people get older. Full time work is found to result in longer social trips. Shorter trips were found for people in urban as well as rural areas. Trips for the purpose of visiting or joint activities tend to be longer than average. With regard to transport mode choice the results indicate that older seniors (75+) are less likely to choose the bicycle, relative to driving. No other significant age effects were found. Significant effects were found for gender, household structure, education level, car ownership, having a disability, urban density, distance and the purpose of the social activity.  相似文献   

18.
New Zealand's airport industry has experienced substantial growth over recent years, but few studies have analysed the operational efficiency of New Zealand airports. This paper aims to extend the study of Francis and Lyon (2007) by exploring the efficiency and productivity changes of New Zealand's major airports between 2010 and 2012, using slacks-based measure (SBM) model and the Malmquist productivity index (MPI). The findings suggested that the majority of New Zealand airports increased efficiency and productivity during the period under investigation, but should decrease scale of operations in order to operate at their most productive size. Decomposition of the MPI showed that most New Zealand airports experienced gains in efficiency but, in terms of technology, they have regressed. Four significant factors (i.e. airport hub status, airport operating hours, airport ownership, and the Rugby World Cup 2011) were identified by the Simar–Wilson bootstrapping regression analysis as explaining variations in airport efficiency. Importantly, the significant effect of the Rugby World Cup 2011 (a major sport tournament) on New Zealand's air transport demand and airports' efficiency has been demonstrated in this research.  相似文献   

19.
客观合理地估算调车作业时间是将调车作业纳入调度集中系统自动控制的前提。通过将调车作业时间分解为若干调车行程时分和作业时分,利用写实法建立车站的调车作业时间库,并以此为基础,通过记录实际调车作业时间对调车作业时间库进行修正与补充,使该库日趋完善与客观,从而为调度集中系统进行自律运算提供有效的依据。  相似文献   

20.
Longer and more frequent traffic jams in the Netherlands are increasing the costs of transporting cargo. Tightly scheduled production systems rely on punctual materials movements, but are congestion-induced delays sufficient to stimulate freight mode switching from road to combined road–rail and road–water movements? A survey of Dutch transport companies revealed an estimated 10% of vehicle operating time spent in congested conditions. The perceived impact on transport operations, consumers and service characteristics are reported. Based on the survey findings, a vehicle cost simulation attributed 7% of transport costs to congestion, increasing the attractiveness of multimodal transport and other solutions.  相似文献   

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