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1.
This paper develops and applies the route choice analysis (RCA) toolkit. This GIS-based toolkit generates a suite of over 40 variables describing route characteristics such as distance, travel time, speed statistics, number of intersections, number of turns, number of stop signs/stop lights, and a measure of route circuity, to name a few. The input to the toolkit is one or more routes, which can be obtained from global positioning system (GPS) data or some other means (e.g., shortest path). While the toolkit is designed to support route choice modeling by generating variables that have been tested in previous modeling efforts, we demonstrate its utility by testing the hypothesis that workers choose routes to minimize either travel time or distance between home and work. A GPS-enhanced data set of 237 observed routes for home-to-work trips collected for auto drivers in Halifax, Nova Scotia, Canada is used in our analysis. We find that the null hypothesis is refuted - that is, a comparison of observed routes to their shortest-path alternatives based on time and distance via inferential statistics indicates that observed routes are significantly longer compared to their alternatives. This finding suggests that workers may choose routes based on other route attributes. The attributes generated by the RCA toolkit for observed, shortest time, and shortest distance routes are compared and significant differences are noted. 相似文献
2.
《Journal of Air Transport Management》2007,13(5):299-310
This paper uses a Delphi panel of 26 air transport experts to forecast the structure of air transport in the EU in 2015 in respect of network carriers, low cost airlines and passenger behaviour. Secondary research was used to construct a number of scenarios about the future structure and strategy of EU network and low cost airlines and also traveller behaviour. Consensus of opinions was sought amongst the panel in a two-round process. The consensus opinion of the Delphi experts was that; network carrier consolidation will reduce EU players to less than five, there will be only two or three large low cost carriers, Business Class products will disappear on short hauls, and leisure travellers will take an increasing number of multiple short-duration holidays. 相似文献
3.
David Jarach Fabrizio Zerbini Giulia Miniero 《Journal of Air Transport Management》2009,15(6):287-293
The paper makes uses of cognitive mappings developed from personal interviews with a number of European airline executives to examine the differences in managerial attitudes of low-cost and transitional carriers. In particular it explores the extent to which there is a convergence of views regarding the ways various airline models will develop in the future. 相似文献
4.
信息化建设是一个复杂的课题,它涉及到企业的管理体制、人员分工、业务流程等许多具体内容。企业完成一个信息化项目一般需要经过调研与需求分析、详细设计、软件开发和应用测试等5个步骤,在这引些开发建设的实际环节中需要企业与建设方的相互了解和协调配合,为此根据信息化建设和过程管理的实践,对企业和项目建设方在每个开发步骤中的作用和要求进行了分析论述。 相似文献
5.
We have realized that the quantitative analysis of safety data is an advanced technology of unsafely events research. Based on the analysis and statistical research on Air Traffic Control irregular events of 2011 using The Threat and Error Management (TEM) model, we have established the Bayesian network model to perform a precise quantitative analysis on the relevance between the threat, error and undesired states in Air Traffic Control operation. This analysis, based on the prior probability, obtained the relevance of the three kinds of safety information above through studying the respective posterior probabilities of threats or errors under undesired states. The result showed that the relevance of controller communication error and undesired states was 75%, and the relevance of Air Traffic Control threats as well as communication error with undesired states in Air Traffic Control was 13.3% and 25%, respectively. Therefore, this research method is of great significance for improving the mechanism of the Air Traffic Control operation risk management. 相似文献
6.
This study examines the effects of built environment features, including factors of land use and road network, on bicyclists' route preferences using the data from the city of Seattle. The bicycle routes are identified using a GPS dataset collected from a smartphone application named “CycleTracks.” The route choice set is generated using the labeling route approach, and the cost functions of route alternatives are based on principal component analyses. Then, two mixed logit models, focusing on random parameters and alternative-specific coefficients, respectively, are estimated to examine bicyclists' route choice. The major findings of this study are as follows: (1) the bicycle route choice involves the joint consideration of convenience, safety, and leisure; (2) most bicyclists prefer to cycle on shorter, flat, and well-planned bicycle facilities with slow road traffic; (3) some bicyclists prefer routes surrounded by mixed land use; (4) some bicyclists favor routes which are planted with street trees or installed with street lights; and (5) some bicyclists prefer routes along with city features. This analysis provides valuable insights into how well-planned land use and road network can facilitate efficient, safe, and enjoyable bicycling. 相似文献
7.
Discontinuity of air routes is a subject that has been analysed in various ways. For example, the complex network approach focuses on network robustness and resilience due to route interruptions during a relatively short period. Also seasonal interruptions of air routes are a well-documented phenomenon in the context of demand variability. However, only recently discussions emerge on the more permanent cessation of air routes, the route churn. Today, European low-cost carriers frequently apply route churn in their networks. To enable early route churn detection in these networks, a regression model is developed in which route characteristics explain the churning likelihood of individual routes. The results of the econometric analysis show that churn rates are higher during an economic downturn, within the Eastern European market, between the Eastern and the Mediterranean market and between primary airports. In addition, we find that distance and the number of seats offered have a significant negative effect on the churn likelihood. The results also show significant effects of market share, seasonality and route age on the chance of cessation. To conclude, the paper demonstrates substantial differences in churn behaviour amongst specific low-cost carriers. 相似文献
8.
Agata Quattrone Antonino Vitetta 《Transportation Research Part E: Logistics and Transportation Review》2011,47(6):1126-1139
The objective of this work is the specification, calibration and validation of a route choice model distinguishing the phases of set perception and route choice among the alternatives belonging to the chosen set. Route generation is performed with a selective multi-criteria approach; route choice is performed using random and fuzzy utility models. As regards the fuzzy utility models, a new specification of a fuzzy model is introduced. Random and fuzzy utility models are compared and applied on a test road network and were specified and calibrated for national road freight transport on a real Italy-wide network. 相似文献
9.
Ming Hsin Lin 《Transportation Research Part E: Logistics and Transportation Review》2012,48(3):637-651
This paper investigates hub carriers’ airlines-within-airlines (AinA) strategies, intended to establish low-cost divisions offering nonstop flights on rim routes. An initial hub-spoke network is optimal if passenger differentiation between one-stop and nonstop services and via-hub time cost are small. If differentiation is substantial, a mixed one-stop and nonstop (point-to-point) network under AinA is optimal when via-hub time cost is small (large). Low-cost rivals on rim routes weaken AinA adoption and enhance welfare from a monopoly mixed network. In a perfect-substitute case, hub carriers may have excessive incentive to adopt AinA from a welfare viewpoint, especially, when low-cost rivals exist. 相似文献
10.
Recent interests in both vehicle emissions and public health have facilitated the development of more eco-friendly transportation systems. This study developed a multi-criteria evaluation framework to evaluate the effectiveness of traffic calming measures (TCMs) from the various perspectives at the road network level; operational efficiency, traffic safety, environmental and health impacts. The proposed methodology employs four-step sequential simulation experiments, including driving, traffic flow, emissions, and air dispersion simulations. The results obtained from these four simulations are used to evaluate the effectiveness in terms of safety and operational efficiency in addition to environmental and health impacts. A multi-criteria value function based on the weights estimated from the analysis of an analytical hierarchy process (AHP) is applied in the evaluation framework. As an application, chicanes and speed humps widely implemented in Korean school zones were evaluated at the road network level. The proposed simulation-based approach is expected to be effectively used for the decision-making process in selecting better alternatives for TCM. 相似文献
11.
Peter Uittenbogaart 《Journal of Air Transport Management》1997,3(4):217-225
Although liberalization in European air transport business was formally completed with the implementation of the third package of the EU, today the free market effects of abandoning the bilateral system are not yet very manifest. The experiences in the United States indicate that it can last for over a decade before more or less stable competitive positions are set according to liberalized market conditions. The Amsterdam-London route was among the first routes which was liberalized on a bilateral basis. The development of airline competition on this route gives a rather good insight in what might be expected on other European routes the following years. In the ATRG paper, emphasis is laid upon the following competition characteristics: the number of airlines serving the London routes; the frequency offered by these airlines; the average aircraft size; the air fares charged. Special attention is paid to the relative attractiveness of the various airports in the Londen Area. Also the entrance of start-up carriers that offer no frills, no thrills services is covered. 相似文献
12.
Both the sustainable development of China's economy and the deregulation of the China air transport market have acted as a spur for the halting development of low-cost carriers (LCCs) in China. To analyze the development trends of LCCs' network in China, this paper took Spring Airlines, the only LCC in China as an example. First, the winter flight plans of Spring Airlines from 2005 to 2013 were collected. Secondly, the development trends of air transport network of Spring Airlines were explored with methods of mathematical statistics and social network analysis. Additionally, the development trends were analyzed from the levels of navigable cities, air routes and air transport networks. The results show that although Spring Airlines actively launched air routes between tourist cities with non-class I airports, its network has been transformed from a star structure into a complex one with multi-hubs. The development process of the Spring Airlines network can be separated into three stages. In addition, the problems and evolution trends of its network are discussed further. 相似文献
13.
Understanding and modelling route choice behaviour is central to predicting the formation and propagation of urban road congestion. Yet within conventional literature disagreements persist around the nature of route choice behaviour, and how it should be modelled. In this paper, both the shortest path and anchor-based perspectives on route choice behaviour are explored through an empirical analysis of nearly 700,000 minicab routes across London, United Kingdom. In the first set of analyses, the degree of similarity between observed routes and possible shortest paths is established. Shortest paths demonstrate poor performance in predicting both observed route choice and characteristics. The second stage of analysis explores the influence of specific urban features, named anchors, in route choice. These analyses show that certain features attract more route choices than would be expected were individuals choosing route based on cost minimisation alone. Instead, the results indicate that major urban features form the basis of route choice planning – being selected disproportionately more often, and causing asymmetry in route choice volumes by direction of travel. At a finer scale, decisions made at minor road features are furthermore demonstrated to influence routing patterns. The results indicate a need to revisit the basis of how routes are modelled, shifting from the shortest path perspective to a mechanism structured around urban features. In concluding, the main trends are synthesised within an initial framework for route choice modelling, and presents potential extensions of this research. 相似文献
14.
Exploring the network structure and nodal centrality of China’s air transport network: A complex network approach 总被引:4,自引:0,他引:4
This paper uses a complex network approach to examine the network structure and nodal centrality of individual cities in the air transport network of China (ATNC). Measures for overall network structure include degree distribution, average path length and clustering coefficient. Centrality metrics for individual cities are degree, closeness and betweenness, representing a node’s location advantage as being directly connected to others, being accessible to others, and being the intermediary between others, respectively. Results indicate that the ATNC has a cumulative degree distribution captured by an exponential function, and displays some small-world (SW) network properties with an average path length of 2.23 and a clustering coefficient of 0.69. All three centrality indices are highly correlated with socio-economic indicators of cities such as air passenger volume, population, and gross regional domestic product (GRDP). This confirms that centrality captures a crucial aspect of location advantage in the ATNC and has important implications in shaping the spatial pattern of economic activities. Most small and low-degree airports are directly connected to the largest cities with the best centrality and bypass their regional centers, and therefore sub-networks in the ATNC are less developed except for Kunming in the southwest and Urumchi in the northwest because of their strategic locations for geographic and political reasons. The ANTC is relatively young, and not as efficient and well-developed as that of the US. 相似文献
15.
Methods for determining route distances in active commuting - Their validity and reproducibility 总被引:1,自引:0,他引:1
Distance is a variable of pivotal importance in transport studies. Therefore, after checking the validity of a potential criterion method for measuring active commuting route distances, this method was used to assess the validity and reproducibility of four methods of approximating the commuting route distances covered by pedestrians and bicyclists. The methods assessed were: self-estimated distance, straight-line distance, GIS shortest-route distance, and GPS-measured distance. For this purpose, participants were recruited when walking or bicycling in Stockholm, Sweden. Questionnaires and individually-adjusted maps were sent twice to 133 participants. The distances of map-drawn commuting routes functioned as criterion distances. The participants were also asked to estimate their distances. The straight-line distance between origin and destination was measured using map-drawn routes. The shortest route between home addresses and workplace addresses was calculated with three GIS algorithms. Eighty-six trips were measured with GPS. The main results were that test-retest intraclass correlation coefficients (ICC) exceeded 0.99 for all methods, except for self-estimated distance (ICC = 0.76). No order effects existed between test and retest. Significant differences were, however, noted between criterion distance and self-estimated distance (114 ± 63%), straight-line distance (79.1 ± 10.5%), GIS shortest route (112 ± 18% to 121 ± 22%) and GPS distance (105 ± 4%). We conclude that commonly-used distance estimation methods produce systematic errors of differing magnitudes when used in a context of active commuting in suburban and urban environments. These errors can at average level be corrected for, whereas individual relative errors will remain. 相似文献
16.
The abstract representation of a transportation system as a network of nodes and interconnecting links, whether that system involves roadways, railways, sea links, airspace, or intermodal combinations, defines a network topology. Among the most common in the context of transportation systems are the grid, ring, hub-and-spoke, complete, scale-free and small-world networks. This paper investigates the role of network topology, and the topology’s characteristics, in a transportation system’s ability to cope with disaster. Specifically, the paper hypothesizes that the topological attributes of a transportation system significantly affect its resilience to disaster events. Resilience accounts for not only the innate ability of the system to absorb externally induced changes, but also cost-effective and efficient, adaptive actions that can be taken to preserve or restore performance post-event. Comprehensive and systematically designed numerical experiments were conducted on 17 network structures with some relation to transportation system layout. Resilience of these network structures in terms of throughput, connectivity or compactness was quantified. Resilience is considered with and without the benefits of preparedness and recovery actions. The impact of component-level damage on system resilience is also investigated. A comprehensive, systematic analysis of results from these experiments provides a basis for the characterization of highly resilient network topologies and conversely identification of network attributes that might lead to poorly performing systems. 相似文献
17.
Spatial network analysis (SpNA) provides a promising alternative to traditional transport models for the modelling of active travel, because walking and cycling behaviour is influenced by features smaller than the scale of zones in a traditional model. There is currently a need for link-level, city wide modelling of cycling, both to ensure the needs of existing cyclists are catered for in planning, and to model the effects of changing infrastructure in shaping cyclist behaviour. Existing SpNA models treat cyclists and car drivers as if they make navigational decisions in a similar way, which in reality is not the case.This paper presents an SpNA model using hybrid betweenness, which fits cyclist flows in Cardiff, Wales using distance, angular distance, motor vehicle traffic and slope as predictors of route choice. SpNA betweenness is also shown to implicitly capture the effect of urban density on mode choice. As it handles route finding decisions of drivers and cyclists separately, the model presented is also applicable to road safety models examining the interaction between the two classes of road user. The model has low cost of data collection and is reproducible using publicly available network analysis software and open mapping data. Further avenues for modelling the effect of infrastructure on cycling are discussed. 相似文献
18.
19.
Lei Fan William W. Wilson Denver Tolliver 《Transportation Research Part E: Logistics and Transportation Review》2010,46(5):735-749
This paper analyzes the intermodal transportation network of containerized imports to the United States. An optimization model is developed that integrates international and North America inland transport networks. The results indicate optimal ship size, route, port, and interior shipping corridor and are highly reflective of observed shipments. Sensitivity analyzes were performed to evaluate impacts of congestion on capacity constraints as well as the prospective impacts of the alternative routes that are emerging. Results indicate that Prince Rupert is highly competitive for shipments to some markets, but the expansion of the Panama Canal would have lesser impacts on container flows. 相似文献
20.
The main operational concept of Single European Sky ATM Research Programme is the notion of business trajectory. One possible implementation is based on the notion of a contract of objectives; an agreement among the main air traffic management actors on spatial and temporal intervals called target windows. These 4D windows are defined prior to flight departure by the airlines, airports and air navigation service providers to increase punctuality. We use an analytic hierarchy process to assess the opportunity of implementing this concept by considering the views of experts. The findings indicate that there are net benefits for airlines and air navigation service providers but not for airports 相似文献