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1.
ABSTRACT

Numerous methodologies measuring walkability have been developed over the last years. This paper reviews the Walkability Index (WI) literature of the last decade (2009–2018) and highlights some limitations in the current approaches. Only a few studies have evaluated walkability in Latin America, mainly in big cities but not in medium and small-sized cities in the region, which present their own urbanisation dynamics, security issues, sidewalk invasion problems, and poor planning. Furthermore, most WIs in the literature use objective mesoscale variables to assess walkability in a given area. This paper contributes to filling these gaps by generating new evidence from a medium-sized city in Latin America to question if characteristics of the built environment encourage walking trips, as found in the literature, are transferable among regions. The study also proposes a novel index comprised of microscale and mesoscale built environment variables to assess walkability using virtual tools and considering users’ perceptions. The WI estimation relies on ranking probability models. The results of the case study suggest that subjective Security and Traffic Safety are the most crucial factors influencing walkability in these kind of cities, which is different from what is found in the literature from cities in developed countries where Sidewalk Condition and Attractiveness are the most important factors. Security appeared to be strongly associated with a subjective dimension, represented by the fear of crime or perceived risk for crime, instead of the actual occurrence of crimes. This result evidences the importance of the physical attributes of the real world and how they are captured, judged, and processed by pedestrians. Then, regional transferability of WIs needs to be done carefully. Finally, results in this paper highlight the importance of microscale built environment characteristics in the WI formulation in these cities. Results are in line with other research in some cities of the region, which found that microscale variables such as pavement quality and presence of obstacles on the sidewalks are relevant components to promote walkability.  相似文献   

2.

Three origin‐destination matrices of inter‐zonal person trips for a section of the Los Angeles metropolitan region are analyzed using principal component analysis. The matrices represent total person trips, journey‐to‐work trips, and shopping trips. This allows for the identification of a number of sub‐regional travel fields or functional regions within the area. The composition of and interrelationships between these fields and the spatial coincidence of fields defined for different travel purposes are compared with existing and proposed public transit facilities.  相似文献   

3.
Determining the number and location of depots for winter road maintenance (WRM) represents one of the important strategic decisions while planning WRM activities. However, most organizations dealing with WRM make empirically based decisions. Optimizing the number and location of WRM depots has the potential to achieve considerable cost savings, improve mobility and efficiency, as well as reduce environmental impacts. This paper presents two optimization models. The first model determines the location of WRM depots by minimizing the total distance travelled by maintenance vehicles. The second model determines the optimum number and location of WRM depots by minimizing total transportation costs and capital expenditure and operational expenditure of the depots. The models are then applied to the district road network in Serbia. Results show that their application could lead to significant reductions in WRM costs.  相似文献   

4.
Michael Roe 《运输评论》2013,33(3):229-243

This review emerged from an opportunity provided in 1988 to the author to study the process of Hungarian transport planning in general, and that of the major regional city of Pécs in particular.

It begins by outlining the difficulties of obtaining detailed information on transport policy‐making and planning in Eastern Europe, and then goes on to analyse the situation in Hungary as a whole since the early 1960s. The specific situation in Pécs is then discussed in relation to national transport planning, with detailed case studies drawn from problems on the local and regional road network, the growth in car ownership and usage, the development of local and inter‐regional rail services, the provision of adequate local bus services, and the growth of local taxi services.

The problems stemming from State intervention and planning control in local transport are emphasized, as are the increasingly difficult issues of the Hungarian economy in constraining public investment. The paper concludes with a discussion of the relationship of the problems of Pécs with those of urban areas elsewhere in Europe, and emphasizes the particular difficulties faced by East European planners in the future.  相似文献   

5.
Lyu  Pu  Lin  Yongjie  Wang  Yuanqing 《Transportation》2019,46(3):841-857
Transportation - This study contributes to the analysis of the household characteristics and household neighborhood ones affecting the transportation carbon dioxide emissions produced by commuters....  相似文献   

6.
The paper presents the results of a survey carried out in Hong Kong to gauge people’s attitudes towards the environmental aspects of electric cars. The survey shows that people in general recognise the positive environmental benefits of electric cars, but express concerns over their environmental costs, in particular those of battery waste and increased airborne pollutants emitted by power plants when the electricity is produced.  相似文献   

7.
Yan  Longxu  Wang  De  Zhang  Shangwu  Xie  Dongcan 《Transportation》2019,46(3):777-792
Transportation - Assessing jobs-housing balance (JHB) and commuting efficiency is crucial to urban and transport planning. However, the scale dependency problem, meaning that metrics may be biased...  相似文献   

8.
License plate restriction (LPR) policies are currently being implemented in major Chinese cities with the aim of mitigating traffic congestions. Meanwhile, much controversy regarding the effectiveness of the LPR policies is arising. To better understand the impact of the LPR policies, this paper studies commuters’ acceptance of and behavior reactions to the policies after their implementation. A theoretical model was proposed as the first step, followed by a questionnaire survey that was conducted in Tianjin, China, where an LPR policy has been in place since March 2014. Car owners frequently commuting within the restricted area were sampled as respondents, and a multi-variable regression method was employed to analyze the collected survey data. The results indicate that it is necessary to promote public’s acceptance of the LPR policy, because lower acceptance will lead to more negative reactions towards the policy, which may weaken its effectiveness. Main factors affecting the level of acceptance of the policy are also found, which may serve as a reference for transportation authorities seeking to increase commuters’ acceptance of the policy. These findings are beneficial to designing and implementing LPR policies.  相似文献   

9.
Electric travelling appears to dominate the transport sector in the near future due to the needed transition from internal combustion vehicles (ICV) towards Electric Vehicles (EV) to tackle urban pollution. Given this trend, investigation of the EV drivers’ travel behaviour is of great importance to stakeholders including planners and policymakers, for example in order to locate charging stations. This research explores the Battery Electric Vehicle (BEV) drivers route choice and charging preferences through a Stated Preference (SP) survey. Collecting data from 505 EV drivers in the Netherlands, we report the results of estimating a Mixed Logit (ML) model for those choices. Respondents were requested to choose a route among six alternatives: freeways, arterial ways, and local streets with and without fast charging. Our findings suggest that the classic route attributes (travel time and travel cost), vehicle-related variables (state-of-charge at the origin and destination) and charging characteristics (availability of a slow charging point at the destination, fast charging duration, waiting time in the queue of a fast-charging station) can influence the BEV drivers route choice and charging behaviour significantly. When the state-of-charge (SOC) at the origin is high and a slow charger at the destination is available, routes without fast charging are likely to be preferred. Moreover, local streets (associated with slow speeds and less energy consumption) could be preferred if the SOC at the destination is expected to be low while arterial ways might be selected when a driver must recharge his/her car during the trip via fast charging.  相似文献   

10.
Since 2000 it has been formally required in the Netherlands to evaluate major infrastructure projects according to a standard manual. Here the focus is on its application to the Zuider Zee line, a possible rail link to run from the west to the north of the country, starting at Schiphol Airport and ending at the northern towns in the province of Groningen. We put a major emphasis on environmental impacts of the line, including the methods used to estimate impacts and the results. Ways to improve current practice are discussed. A major advantage has been that the environment has been put on the research and policy agenda at an early stage, although insights into the effects of rail infrastructure on the landscape and nature are limited.  相似文献   

11.
The increasing trend of charging for aircraft noise nuisance to encourage the sustainable development of the air transport industry has resulted in a need to evaluate the real social costs of such externalities for the formulation of effective charge mechanisms. After comparing the current charge mechanisms at world airports as well as reviewing existing externality measurements, mathematical models are developed to calculate the noise social cost in monetary terms, and noise charge mechanisms are subsequently established. The hedonic price method is applied to calculate the annual social cost of aircraft noise during the landing and take-off stages of the flight. This is done by estimating the implicit costs of aircraft noise imposed through a decline in property values in the vicinity of the airport. The empirical results, using Amsterdam Airport Schiphol as the case study, show that the current noise charge level imposed by the Dutch Government is lower than the actual noise social cost resulting from aircraft movements. Several noise charge mechanism scenarios are derived according to the modelling results, as well as the environmental objectives of the airport related authorities.  相似文献   

12.
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   

13.
This paper develops a systematic and practical construction methodology of a representative urban driving cycle for electric vehicles, taking Xi’an as a case study. The methodology tackles four major tasks: test route selection, vehicle operation data collection, data processing, and driving cycle construction. A qualitative and quantitative comprehensive analysis method is proposed based on a sampling survey and an analytic hierarchy process to design test routes. A hybrid method using a chase car and on-board measurement techniques is employed to collect data. For data processing, the principal component analysis algorithm is used to reduce the dimensions of motion characteristic parameters, and the K-means and support vector machine hybrid algorithm is used to classify the driving segments. The proposed driving cycle construction method is based on the Markov and Monte Carlo simulation method. In this study, relative error, performance value, and speed-acceleration probability distribution are used as decision criteria for selecting the most representative driving cycle. Finally, characteristic parameters, driving range, and energy consumption are compared under different driving cycles.  相似文献   

14.
Fuel consumption is calculated using a modelling procedure for automobiles travelling on three alternative street patterns designed for a subdivision in Kingston Township, Ontario. The modelling procedure is described. The results indicate that grid and solar superblock street patterns, compared to the existing street pattern, offer small fuel savings to a tripmaker in the portion of the work trip travelled in the subdivision.  相似文献   

15.
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   

16.
This study explores the optimal investment in the length of an expanded section of road to mitigate the congestion on a transportation corridor. It is assumed that one end of the road is in the central business district (CBD) and that the households are uniformly distributed along the road. Each individual makes trips from his/her residence to the CBD. Trip demand is elastic and depends on the cost of the trip (including congestion costs). During the first stage, the government determines the length of the expanded section given the width of that section. In the second stage, road users determine their trip demands by taking into consideration the trip cost function. In the process of solving this problem, the equilibrium traffic volume is first solved using differential equations. The optimal length of the expanded section is then solved by maximizing the social welfare. The analysis is then applied to the case of the Tucheng city – Banciao city – Taipei CBD corridor in the Taipei metropolitan area. The scheme of road expansion without tolling performs closely to the first-best scheme for the case of a high potential demand. This study’s approach can serve as valuable reference for city planners engaged in road planning in a transportation corridor between the CBD and satellite cities in a metropolitan area.  相似文献   

17.
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   

18.
Chen  Mengwei  Wang  Dianhai  Sun  Yilin  Waygood  E. Owen D.  Yang  Wentao 《Transportation》2020,47(2):689-704

The paper takes station-based bikesharing system (SBS) with docks and dockless free-floating bikesharing system (FBS) as two targets to dig out the relationship between users and use frequency of the services for each scheme, and how the relationship varies from scheme to scheme. To achieve this, studies are carried out focusing on three questions: “who are using these two bicycle services?”; “what are the factors influencing the use frequency of both bicycle systems?”; and “which specific level of the factors influencing the use frequency of both bicycle schemes?” To collect data from users, a survey was designed containing questions for user attributes and service experience and conducted jointly on-line and on-site at four locations with mixed land use in Hangzhou, China. Analysis results show that SBS and FBS have similar user structure but different factors influence use frequency. Based on analysis results, from the user perspective, SBS’s strength is to have good quality with low cost while FBS is more flexible and free to use. Finally, recommendations for SBS are to involve more technology to expand its range to aided bikes for senior citizens and open the access for a mobile renting system, whereas for FBS, it is critical to get government cooperation and for operators to add parking area restrictions into the cellphone application, and create an on-line platform where users can find all the free-floating bike information.

  相似文献   

19.
This paper examines air traffic patterns among China’s scheduled airlines in January 2006 and January 2011, using Official Airline Guide data on carrier schedules. The author classifies Chinese carriers into one of four classes. Airports are also organized into a classification scheme based on several criteria related to the total volume of traffic, the carriers serving the airports and the nature of the airports to which they are connected. Counts, sums, percentage shares and changes in these calculations between 2006 and 2011 are presented in tabular form. Inferences about the fundamental structure and future patterns of capacity growth for the yet not fully emerged Chinese air traffic system can be drawn.  相似文献   

20.
Le Vine  Scott  Kong  You  Liu  Xiaobo  Polak  John 《Transportation》2019,46(4):1215-1244
Transportation - The study evaluates, in the context of freeway segments, the interaction between automated cars’ kinematic capabilities and the standard legal requirement for the operator of...  相似文献   

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