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1.
A. MAJUMDAR 《运输评论》2013,33(2):135-176
Air traffic in the UK has increased rapidly in the past two decades and is forecast to grow at a rate of 4.3% per annum between 1998 and 2020. The failure to develop the air traffic system in order to cope with this growth has had undesirable consequences, e.g. a rise in flight delays and near misses. Given the investment required in air traffic control systems to cater for this growth, the UK government in 2000 part privatized the National Air Traffic Services (NATS), the body in charge of the UK's airspace in a public–private partnership (PPP). The UK Airline Group acquired 46% of NATS and effective operational control, though the government retains a share in NATS and safety regulation is in the public sector. However, serious doubts about safety were raised during the debate on the PPP. Similar moves towards a commercial operation (i.e. corporatization) of air navigation services have been made in New Zealand and Canada over the past decade and these provide useful insights into the results of the corporatization process. This paper analyses the main issues surrounding the part privatization of NATS. First, it highlights the experience from New Zealand and Canada of the major issues involved in corporatized air navigation services in six different categories: funding, new technology and project management, safety, pricing regime, international opportunities, and customer responsiveness. The likely impacts for NATS given the lessons from New Zealand and Canada are considered. The UK government's provisions for the PPP and their implementation in the post‐PPP NATS are then outlined for these six categories. Finally, the 11 September 2001 terrorist attacks have had major impacts on air travel and their consequences for NATS in the six categories are highlighted. This paper concludes with some of the issues that need to be addressed to ensure the success of the PPP for NATS.  相似文献   

2.
This study investigates the impact of using a concept map-based ‘mashup’ (www.accessadvisr.net) to provide volunteered (i.e. user contributed) ease of access information to travellers with limited mobility. A scenario-based user trial, centred around journey planning, was undertaken with 20 participants, divided equally between (1) those who have physical restrictions on their mobility, due to disability, illness or injury, and (2) those with practical mobility constraints due to being parents with young children who have to use a child’s pushchair when using public transport. Both user groups found the concept useful, but its potential impact was less for the pushchair user group. There were mixed views in relation to the ability of the mashup to convey the trustworthiness, credibility and reliability of information necessary for journey planning. The study identified a number of key information-related user requirements which help enable effective design of user contributed web-based resources for travellers with mobility-related issues.  相似文献   

3.
Kim  Hyunjin 《Transportation》2021,48(1):167-192
Transportation - In conjunction with their gender, how does the current design of public transport services affect female passengers’ feelings of safety and fear when using the service? This...  相似文献   

4.
Advances in Information and Communication Technologies (ICT) allow the transportation community to foresee dramatic improvements for the incoming years in terms of a more efficient, environmental friendly and safe traffic management. In that context, new ITS paradigms like Cooperative Systems (C-ITS) enable an efficient traffic state estimation and traffic control. C-ITS refers to three levels of cooperation between vehicles and infrastructure: (i) equipped vehicles with Advanced Driver Assistance Systems (ADAS) adjusting their motion to surrounding traffic conditions; (ii) information exchange with the infrastructure; (iii) vehicle-to-vehicle communication. Therefore, C-ITS makes it possible to go a step further in providing real time information and tailored control strategies to specific drivers. As a response to an expected increasing penetration rate of these systems, traffic managers and researchers have to come up with new methodologies that override the classic methods of traffic modeling and control. In this paper, we discuss some potentialities of C-ITS for traffic management with the methodological issues following the expansion of such systems. Cooperative traffic models are introduced into an open-source traffic simulator. The resulting simulation framework is robust and able to assess potential benefits of cooperative traffic control strategies in different traffic configurations.  相似文献   

5.
6.
In Niamey, private motor vehicles carry 80% of those who use public transport. These vehicles are urban shared taxis called ‘redheads’ and run through the streets of the city in all directions. Their vital importance for the mobility of city‐dwellers justifies their strict supervision and the setting of fares by public authorities.

At present, the ‘redheads’ are in crisis. Taxi owners are no longer able to make a profit on their capital and are ceasing to invest. Urban buses are unable to replace taxis, for they operate at a large deficit. The government of Niger hopes to restore the level of transport service by means of new regulations for the taxi business in the city.

But this business is in the hands of both taxi owners and drivers, who, while partners in the operation, dispute over their share of the revenues. The aim of this article is to provide an economic and political analysis of this particular form of production of urban transport, in which employers who cannot control their companies, employees who reserve the profits of the business for themselves, and public authorities who are compelled to intervene, are coming face to face.  相似文献   

7.
Transport choices are not merely practical decisions but steeped in cultural and societal perceptions. Understanding these latent drivers of behaviour will allow countries to develop and import policies to more successfully promote sustainable transport. Transport symbolism – what people believe their ownership or use of a mode connotes to others about their societal position – has been shown to be one such, non-trivial, hidden motivator. In the case of hybrid and electric cars (‘eco cars’), studies have demonstrated how their symbolic value varies within a society among different social groups. As yet, however, there has been scant research into comparing how the symbolism of a mode varies across national cultures, horizontally, between individuals with similar socio-demographic characteristics. Through qualitative thematic analysis, this study utilises two of Hofstede’s cross-cultural indices – power differential and individualism versus collectivism – to develop and strengthen theory on how the differing symbolism of eco cars currently varies between four cultural clusters – Anglo, Nordic, Confucian and South Asian. It also deliberates how observed symbolic qualitative differences may influence an individual or group choice to procure eco cars. Finally, it discusses how policy development, transfer and marketing, within the context of eco cars, may need to be modified by national governments, in the Confucian and South Asian cultures, so as to encourage uptake and modal shift.  相似文献   

8.
Abstract

Inland vessels move goods along waterways (canals and rivers) and they visit ports. Because of their tidal nature, vessels make use of locks to enter ports or waterways. From a port management point of view, fast access to and from the port and high utilization of locks are important objectives. Where the former relates to low inbound and outbound waiting times, the latter relates to the placement of as many vessels as possible in the lock before its operation. This article includes a case study that relates to the operation of the Van Cauwelaert lock in the port of Antwerp, Belgium. Lock operation policy is as follows: vessels wait in front of the lock for a port administrator to assign places in the lock based on knowledge of the vessels’ dimensions. As such, there is no FIFO-discipline, but a ‘group-FIFO’-discipline, i.e. if n vessels are allowed into the lock, they are the first n vessels in the arrival queue. A heuristic algorithm is formulated for the placement of vessels in the lock. This algorithm supports the decision where to place the vessel in the lock, aiming to place as many vessels as possible from the arrival queue. At the same time, it supports the decision to start a locking operation or not, based on information about vessels that are announced but which have not yet arrived at the lock's entrance. The heuristic is called a ‘less-flexibility-first’-heuristic as it looks for pseudo-placements, showing which flexibility is left for the remaining vessels after placing a vessel. This article describes the implementation of the heuristic and provides numerical examples. A comparison is made between the heuristic results and daily practice, based on real-life vessel movements through the Van Cauwelaert lock in 2002.  相似文献   

9.
Car use per person has historically grown year-on-year in Great Britain since the 1950s, with minor exceptions during fuel crises and times of economic recession. The ‘Peak Car’ hypothesis proposes that this historical trend no longer applies. The British National Travel Survey provides evidence of such an aggregate levelling off in car mileage per person since the mid-1990s, but further analysis shows that this is the result of counter trends netting out: in particular, a reduction in per capita male driving mileage being offset by a corresponding increase in female car driving mileage. A major contributory factor to the decline in male car use has been a sharp reduction in average company car mileage per person. This paper investigates this aspect in more detail. Use of company cars fell sharply in Britain from the 1990s up to the 2008 recession. Over the same period, taxation policy towards company cars became more onerous, with increasing levels of taxation on the benefit-in-kind value of the ownership of a company car and on the provision of free fuel for private use. The paper sets out the changes in taxation policy affecting company cars in the UK, and looks at the associated reductions in company car ownership (including free fuel) and patterns of use. It goes on to look in more detail at which groups of the population have kept company cars and in which parts of the country they have been most used, and how these patterns have changed over time. A preliminary investigation is also made of possible substitution effects between company car and personal car driving and between company car use and rail travel. Clearly, the role of the company car is only one of many factors that are contributing to aggregate changes in levels of car use in Great Britain, alongside demographic changes and a wide range of policy initiatives. But, company car use cannot fall below zero, so the effect of declining year-on-year company car mileage suppressing overall car traffic levels cannot continue indefinitely.  相似文献   

10.
This paper presents the evaluation results of three traffic solutions for the complex grade-separated intersection located in the old part of Belgrade at the junction with the new bridge over the Sava River. The corridor to which the intersection belongs together with the new river bridge are parts of a great urban artery called the Inner Half Semi-Ring Road (IHSRR). The traffic solutions that are evaluated are defined in the preliminary design phase, based on two opposed concepts: a complete grade separation of all intersection legs (the CPV alternative – ‘grade-separated’) and a grade separation designed to minimise construction costs (DMC 1 and 2 alternatives – ‘minimise cost’). The evaluation procedure is conducted in three steps: first, the score based on expert assessment of the functionality of the design solutions is determined; second, the alternatives are ranked according to the value of a set of state indicators obtained by micro-simulation using PTV–VISSIM 4.10; and third, the final score is obtained by multi-criteria evaluation using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. The results of the first evaluation step show a small advantage for DMC 2, a sub-alternative of the DMC 1 alternative. The results of the micro-simulation give advantage to the DMC 1 alternative. The multi-criteria evaluation provides a better ‘goodness factor’ for the CPV alternative against the DMC 1 alternative. At the same time, the least construction cost favours alternative DMC 1.  相似文献   

11.
Transportation - More and more cities worldwide are striving for sustainability and livability. Measuring the service or performance of local-scale spaces for pedestrians and bicyclists to better...  相似文献   

12.
13.
The Remotely Piloted Commercial Passenger Aircraft Attitude Scale (RPCPAAS) was created to measure positive and negative attitudes towards a new and plausible form of air travel. This information was then used, in combination with a latent class logit model built on data generated from a stated choice experiment to gain insight into the choice behaviour between conventionally piloted aircraft (CPA) with a pilot on-board and remotely piloted aircraft (RPA) with a pilot on the ground. The results revealed that individuals, on-average, if presented a choice between a CPA and a RPA of equivalent attributes, would elect for the CPA option. However, there is variability in the passengers’ sensitivity to various flight attributes, and these sensitivities were influenced by individuals’ attitude towards the new technology (i.e., RPA). From an operational perspective, and assuming that one day passengers of commercial airlines are offered the choice between CPA and RPA, the strategies employed by airlines to encourage the use of the new technology need to be different, based on individuals’ attitude towards RPA.  相似文献   

14.
Pellegrini  Andrea  Sarman  Igor  Maggi  Rico 《Transportation》2021,48(2):931-951
Transportation - This article analyzes the determinants of tourists’ expenditure behavior through the joint adoption of two microeconometric approaches, namely, the Stochastic Frontier (SF)...  相似文献   

15.
Tourism is a noticeable contributor to global greenhouse gas (GHG) emissions. Existing estimates of tourism’s carbon footprint are however incomplete as they fail to holistically assess the additional, ‘indirect’ carbon requirements. These arise from the non-use phases of a tourism product or service life cycle and can be further magnified by supply chain industries. Under-development of methods for carbon impact assessment in tourism is the primary reason for the omission of ‘indirect’ GHG emissions. This study develops a new approach for comprehensive appraisal of GHG emissions which incorporates and advances the methodological advantages of existing assessment techniques. It tests the applicability of this approach in tourism by conducting a holistic analysis of a standard holiday package to Portugal, based on the British tourism market. The new approach demonstrates the significance of the ‘indirect’ GHG emissions in the total carbon footprint from the holiday package, thus emphasising the necessity for more comprehensive future assessments.  相似文献   

16.
Summary

(1) The response of an individual consumer to change in such characteristics as price will be to change behaviour at a critical point, a ‘threshold’ at which a change of behaviour is perceived to be beneficial.

(2) Most choices can be viewed as binary, for example, between pairs of transport modes. A cumulative normal distribution of responses will give an S‐shaped curve, the mid‐point being at the average threshold value.

(3) An aggregate demand curve should show the response of a given group of people to a range of price changes at one point in time. Most curves derived from revealed behaviour do not permit this. To some extent, a demand curve must be derived from interviews and other tests, giving hypothetical behaviour. Such methods are used in non‐transport consumer tests, and work by Brög et al. gives a similar picture for transport users, supporting the concept of the S‐shaped curve.

(4) Allowance for frequency of trip‐making modifies this picture, suggesting that a smoother curve may be appropriate for some conditions, such as non‐work trips. These approaches may be combined by use of catastrophe theory, with two control factors. The hysteresis effect is found around the threshold where repeated changes in the basic stimulus produce successively smaller responses.

(5) There is some evidence of symmetrical response by public transport users to real increases and reductions in cash‐paid graduated fares, but this is not the case where different forms of pricing are involved.

(6) An example of threshold effects in private transport may be found in the monitoring of tolls on the Itchen Bridge by Atkins. Demand became particularly sensitive to price in a certain range.

(7) In the public transport field, there is similar evidence from the experience of introducing flat or zonal fares where graduated fares previously applied. Where travelcards are sold, the effect is much greater, and cases such as the West Midlands show little if any effect on sales despite real price increases. Here, trips are about 7% higher than would have been expected for the same revenue target, had graduated fares been retained. However, it may well be possible to exceed the threshold, especially where fares simplification and increases are combined, as the Trondheim experience suggests.  相似文献   

17.
George Town, Penang, is the oldest British colonial city in South East Asia. The colonial settlement layout in the inner city area is still intact today. The establishment of George Town as a trading centre had attracted immigrants from all over the world, especially from Asia (Chinese, Indians and Arabs). Recently, George Town has been enlisted under the UNESCO World Heritage Lists as an outstanding example of traditional multi-cultural settlement. The uniqueness of this inner city is that the formation of its urban pattern is the result of ‘divide and rule’ concept adopted by the British authority. Under the ‘divide and rule’ concept, these immigrants were located to settlement areas based on their ethnic background under one leader known as ‘kapitan’ (captain). The study finds that transport access in this inner city was influenced by the ‘divide and rule’ concept. Unlike formation of well-planned gridiron pattern in other British colonial cities such as in North America, Canada and Australia, the formation of the urban pattern in George Town has an irregular gridiron pattern. This type of urban pattern is typical under ‘divide and rule’ concept and this had indirectly influenced the setting and planning of the present street access and transport networks.
Ahmad Sanusi HassanEmail:
  相似文献   

18.
ABSTRACT

This narrative review synthesised the limited work that has been carried out into road safety education targeting parents. Parent education appeared to have a positive impact on child safety seat use and children’s bike helmet use, but results regarding the impact of parent education on pedestrian safety were mixed. The review highlighted important gaps in the literature. A key gap being identifying effective ways to engage parents of low socioeconomic and ethnic minority backgrounds. Further, another gap is understanding effective ways to engage and support parents of children with additional needs to build their children’s road safety skills. There is some evidence that parent education has a positive impact on these “at-risk” groups, but little work on how to engage with these groups and the type of parent education required.  相似文献   

19.
This paper demonstrates that commonly used methods for eliciting value of time can give downward bias and investigates whether this can be reversed by ‘referencing’ as has been suggested (e.g., by Hensher in Transp Res B 44:735–752, 2010), i.e. with attributes of choice alternatives pivoted around a recently made journey. Value-of-time choice experiments were conducted in two rounds. In the first round, real and hypothetical purchases of performance of a simple time-consuming task were done to assess hypothetical bias; in the second round, participants were asked to do hypothetical travel choices with and without ‘referencing’ to a specific occasion, to be able to test ‘referencing’ as a remedy to the bias confirmed in the first round. A negative hypothetical bias was found for allocation of time at another occasion than the present (but not for a decision concern allocation of time ‘here and now’). A striking result was held from the second round experiments: ‘referencing’ indeed affects responses, but by reducing the elicited implicit value of time, so any negative hypothetical bias that would exist without ‘referencing’ would have been further magnified by the ‘referencing’ design.  相似文献   

20.
Karel Martens 《Transportation》2012,39(6):1035-1053
This paper seeks to provide a theoretical basis for a distributive approach to transport. Using the theory developed by Michael Walzer in his ??Spheres of Justice?? (1983), I argue that the transport good, defined as accessibility, should be distributed in a so-called separate sphere, i.e. independent from the way in which other key goods, like money or power, are allocated. I subsequently explore what kind of justice principle could guide the distribution of the transport good, once a separate sphere would be established. This preliminary exploration results in the elimination of a number of widely supported distributive principles, and in the tentative identification of a criterion matching the particularities of the transport good. The explorations in the paper are not intended as final answers, but rather seek to open the debate about the need for an explicit distributive transport policy and the distributive principle that should guide such a policy.  相似文献   

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