A comparison of three methods for assessing the walkability of the pedestrian environment

This paper presents the results of a research project conducted in the UK designed to increase understanding of the factors which influence levels of walking and pedestrian route choice. It describes a number of techniques that were used to assess the pedestrian environment from a pedestrian’s perspective. These techniques included a computer based tool developed using stated preference surveys to determine the relative values of a range of factors in the pedestrian environment; an on-street survey that was designed to investigate values and attitudes towards different attributes of the pedestrian environment along a route; and finally an ‘on the move survey’ where pedestrian volunteers were interviewed while walking along the route in order to get an actual account of their experiences as they walk. A case study is then used to show the benefits and disadvantages of using these different techniques and compares results for a pedestrian route in the City of Leeds in the UK. The results indicate that there were a number of pedestrian attributes considered important by pedestrians when walking including pavement cleanliness, safe crossing places, good connectivity and sense of security. The three approaches complement one another and have highlighted in different ways that the walking experience is affected by the cumulative impact of multiple interactions (both positive and negative) as people walk in the pedestrian environment.     

Polygonization method for automatic generation of indoor and outdoor pedestrian navigation path for smart city

Smart mobility cannot be supported by smart technologies alone. It has to be supported by geospatial data with navigation lines. Manual methods for creating and updating them are not only costly but also time-consuming. Automatic extraction and updating of geospatial navigation lines from GIS and indoor layout plans are much needed. The navigation path is often stored and conceived as centreline graphs in GIS. However, navigation paths in which the centrelines are located can be considered as a combination of basic navigation polygons. This paper proposed a generic polygonization method that can automatically generate and update navigation centrelines from GIS and BIM. By constructing basic navigation polygons from GIS and decomposing path polygons in street layouts and floor plans from GIS and BIM into basic navigation polygons, indoor and outdoor pedestrian navigation paths and centrelines can be extracted and generated to be used for indoor and outdoor pedestrian navigation.     

Network Robustness Index: A new method for identifying critical links and evaluating the performance of transportation networks

Highway planning efforts, especially those involving capacity expansions, have traditionally relied on the volume/capacity (V/C) ratio to identify “highly congested” or critical links, resulting in localized solutions that do not consider system-wide impacts. This paper presents a new, comprehensive, system-wide approach to identifying critical links and evaluating network performance. The approach considers network flows, link capacity and network topology. Moreover, it relies on readily available sources of data. Using three hypothetical networks, we demonstrate that the approach, known as the Network Robustness Index, yields different highway planning solutions than the traditional V/C ratio. Moreover, these solutions yield far greater system-wide benefits, as measured by travel-time savings, than solutions identified by the V/C ratio.     

Analysis of the impact of street-scale built environment design near metro stations on pedestrian and cyclist road segment choice: A stated choice experiment

The mismatch between the design of the micro-scale built environment around metro stations and pedestrian/cyclist preferences causes inconvenience and dissatisfaction. How to design streets near metro stations to provide a walking/biking friendly built environment is still a key question in promoting the use of metro systems. To identify which general attributes of the street-scale built environment are relevant for pedestrians/cyclists and increase walkability/cycle-ability, this paper reports the results of a stated choice experiment in which eight built environment attributes were systematically varied: street segment length, average number of building floors on both sides of the street, retail shops in frontage of streets, street crossing facilities for pedestrians/cyclists, width of sidewalks/bicycle paths, greenery, density of street lamps and crowdedness of pedestrian/cyclists to understand their influence on a road segment choice and preferences. A total of 803 respondents were recruited from Tianjin, China to complete the stated choice experiment through on-street face-to-face interviews. A multinomial logit model was estimated to unravel pedestrian/cyclist preferences using the stated choice data. The results indicate that pedestrians and cyclists have similar preferences for road segments with building lower than 6 floors, 50% retail shops in frontage, more greenery, lamps between 15 m and 30 m, more crossing facilities, wider sidewalk/bike lane and not crowded. These significant built environment attributes can be used in urban design projects with a walking/biking friendly built environment around a metro station.     

Assessing policy measures for the stimulation of intermodal transport: a GIS-based policy analysis

Intermodal transport is the combination and integration of several transport modes (such as rail, inland waterways with road transport). In order to make the transhipment easy and efficient standard loading units are used, such as containers or swap-bodies. As for the main haul, more environmental friendly modes are used (rail and inland waterways) and a modal shift towards these modes can help in reducing the congestion. Therefore several policies are directed to stimulate the intermodal transport market.In this paper, a location analysis model for Belgian intermodal terminals (LAMBIT) is developed and used to assess different policy measures in Belgium. The simulations show that the different policy measures oriented towards the rail/road and inland waterways/road combinations should be incorporated in a coherent, integrated vision, in order to not create a modal shift between the different intermodal transport options. The methodology can easily be extended towards a European scale.     

An empirical procedure for enhancing the impact of road investments

The importance of ‘needs based planning’ is increasingly being recognised by road authorities. Such planning entails allocation of resources to explicitly account for the requirements of the community well into the future. Accomplishing what the community requires of a road system, at least at a level desired by them and ensuring regional equity in meeting community requirements, are two issues that are at the fore-front of needs based planning. This paper demonstrates that, in order to achieve these planning objectives it is necessary to adopt a procedure that can identify road investment proposals with the maximum ability to cost-effectively generate what the community perceive as gain in value to them due to road investment. Using data collected for Western Australia, the paper illustrates that generating investment proposals by commonly used approaches—including conventional multi-criteria analysis—cannot satisfactorily address these issues.     

Policy-sensitive selection and phasing of road investments with a goal program

A goal program to select and schedule road projects can include policy considerations in addition to those covered by cost-benefit evaluation. Five economic benefits and twelve environmental, developmental and accessibility objectives constitute the goals in a rural application in Western Australia. A plan and construction schedule can be generated for any set of priorities, each satisfying the budget constraint. Government can choose from them to match current policy concerns and meet the needs of affected residents. The method is particularly valuable when there are linkages between projects.     

A GIS-based time-geographic approach of studying individual activities and interactions in a hybrid physical–virtual space

Modern information and communication technologies (ICT) are changing human activity and travel patterns that could have significant implications to our everyday lives and the human organization of space. Time geography, which examines human activities under various constraints in a space–time context, provides a useful framework to analyze the complex spatio-temporal relationships among activities and interactions taking place in both physical and virtual spaces. However, virtual activities and interactions conducted via ICT have characteristics that cannot be properly represented and analyzed under the classical time-geographic framework. This paper extends classical time-geographic concepts to accommodate the needs of representing and analyzing all activities and interactions in a hybrid physical–virtual space. In addition, this paper presents a space–time geographic information system (GIS) design that is capable of organizing complex activity and interaction data as spatio-temporal processes in an integrated space–time environment. This space–time GIS design offers a useful analytical environment for researchers to study increasingly dynamic human activity and travel patterns in today’s society and their implications toward changing travel demand patterns from both spatial and temporal perspectives.     

Varying influences of the built environment on daily and hourly pedestrian crossing volumes at signalized intersections estimated from traffic signal controller event data

Direct-demand models of pedestrian volumes (identifying relationships with built environment characteristics) require pedestrian data, typically from short-duration manual counts at a limited number of locations. We overcome these limitations using a novel source of pedestrian data: estimated pedestrian crossing volumes based on push-button event data recorded in traffic signal controller logs. These continuous data allow us to study more sites (1494 signalized intersections throughout Utah, US) over a much longer time period (one year) than in previous models, including the ability to detect variations across days-of-week and times-of-day. Specifically, we develop direct demand (log-linear regression) models that represent relationships between built environment variables (calculated at ¼- and ½-mile network buffers) and annual average daily and hourly pedestrian metrics. We control spatial autocorrelation through the use of spatial error models. All results confirm theorized relationships: There is more pedestrian activity at intersections with greater population and employment densities, a larger proportion of commercial and residential land uses, more connected street networks, more nearby services and amenities, and in lower-income neighborhoods with larger households. Notably, we also find relevant day-of-week and time-of-day differences. For example, schools attract pedestrian activity, but only on weekdays during daytime hours, and the coefficient for places of worship is higher in the weekend model. K-fold cross-validation results show the predictive power of our models. Results demonstrate the value of these novel pedestrian signal data for planning purposes and offer support for built environment interventions and land use policies to encourage walkable communities.     

A GIS-based Bayesian approach for analyzing spatial–temporal patterns of intra-city motor vehicle crashes

This paper develops a GIS-based Bayesian approach for intra-city motor vehicle crash analysis. Five-year crash data for Harris County (primarily the City of Houston), Texas are analyzed using a geographic information system (GIS), and spatial–temporal patterns of relative crash risks are identified based on a Bayesian approach. This approach is used to identify and rank roadway segments with potentially high risks for crashes so that preventive actions can be taken to reduce the risks in these segments. Results demonstrate the approach is useful in estimating the relative crash risks, eliminating the instability of estimates while maintaining overall safety trends. The 3-D posterior risk maps show risky roadway segments where safety improvements need to be implemented. Results of GIS-based Bayesian mapping are also useful for travelers to choose relatively safer routes.     

Multivariate analysis of the impacts of NAS investments: A case study of a capacity expansion at Dallas-Fort Worth Airport

Multivariate statistical analysis is used to estimate the impacts of a major capacity expansion at Dallas-Fort Worth International Airport. The model relates the Daily Flight Time Index (DFTI) to demand, weather, origin airport congestion, and the expansion itself. The effect of the capacity expansion on DFTI is found to depend strongly on visibility. On average, the index in the post-expansion period is 1.3 min less as a consequence of investment. This change includes a larger reduction in departure delay that is offset by an increase in taxi time. Moreover, the reduction caused by the expansion has been more than offset by increases in the DFTI resulting from other factors, notably increased demand and worse weather.     

Risk and a changing environment for Antarctic tourism

This research note explores the issues of perceptions of risk and a changing environment for Antarctic tourism. A pilot study was undertaken aboard an Antarctic cruise ship in February 2008 with the purpose of examining the views of passengers about risk and environmental change in light of the recent sinking of the Explorer and the growing awareness of climate change effects in polar regions.     

Identifying resident preferences for bus-based and rail-based investments as a complementary buy in perspective to inform project planning prioritisation

Much of the debate associated with the development of new public transport infrastructure appears to have an emotional bias with communities in favour of one mode, especially rail. This, in turn, carries much sway at the political level as if there is no budget constraint or consideration of value for money and coverage. This paper presents a stated choice experiment to investigate this context as two unlabelled options described by 20 potential drivers of community preferences for improved public transport. Each choice scenario is conditioned on a given route length but with different costs, reflecting different modal investment options for the same route length. To establish whether a modal bias exists within and between geographical jurisdictions, the choice scenario is followed by a labelling of each investment option to reveal whether the option is bus rapid transit (BRT) or light rail transit (LRT). Data from all eight capital cities of Australia, collected in mid-2014, form the empirical setting. Mixed logit random regret models provide new evidence on the nature and extent of community modal bias in this choice setting. The paper also proposes a complementary tool to benefit-cost analysis that uses the residence preferences model to show, through scenario analysis, the potential gains in public support for BRT over LRT. The results suggest that BRT should be in the mix of candidate projects if more than one mode is considered and not ignored, as is so often the case in developed economies.     

A method for the design of optimal transport strategies

This paper presents a methodology for the design of optimal transport strategies and demonstrates its application to six UK cities. An objective function representing the total welfare of a transport strategy is used to measure the performance of the strategy; the levels of policy instruments in a strategy, such as changes in public transport fares and frequency, are chosen such that the objective function is optimised. Two types of analysis are reported: sensitivity tests around individual policies to examine their relative impacts, and optimisations of packages of transport policies. The effects of spatial variations of the PT policies in the optimisations are also investigated.     

A fully fuzzy network DEA-Range Adjusted Measure model for evaluating airlines efficiency: A case of Iran

Due to the competition among companies, evaluating the performance is one of the most important issues for managers. Data Envelopment Analysis (DEA) - Range Adjusted Measure model (RAM) is one of the non-radial models to evaluate the performance of companies. This paper presents a fully fuzzy network DEA-RAM model for evaluating airlines and extends the network DEA-RAM model in the fully fuzzy framework. First, a network structure is designed for airlines and then, a DEA-RAM model is presented for calculating efficiency scores. To handle uncertainty in data, fully fuzzy approach is considered and finally, a multi-objective network model is proposed to calculate airlines’ efficiencies. To solve the proposed fully fuzzy DEA-RAM model, the lexicographic approach is used and the efficiency scores are reported as interval numbers. To illustrate the capability of the proposed fully fuzzy DEA-RAM model, the actual data of 14 Iranian airlines are gathered and the interval efficiencies of airlines are evaluated.     

A multi-criteria analysis framework including environmental and health impacts for evaluating traffic calming measures at the road network level

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.     

A deeper investigation into the effect of the built environment on the use of ridehailing for non-work travel

Ridehailing has become a main-stream mobility option in many cities around the world. Many factors can influence an individual's decision to use ridehailing over other modes, and the growing need of policy makers to make built-environment and regulatory decisions related to ridehailing requires an increased understanding of these. This study develops a model that estimates how the built environment affects the decision to choose ridehailing for making non-work trips, while carefully accounting for a variety of confounding effects that could potentially bias the results (if ignored or improperly incorporated). These include: total number of trips, differences in supply between urban and non-urban areas, residential choice (e.g. urban versus non-urban areas), and household choice of whether to own a vehicle. We use individual-level data from a California travel survey that includes detailed attitude measurements to estimate an integrated choice and latent variable (ICLV) model to properly specify these effects. We include accessibility measures used elsewhere (e.g., Walkscore) plus measures developed for this study. Our analysis estimates the effect of these measures on ridehailing mode share, and how they differ between urban and non-urban areas. This analysis results in several major findings: we confirm that omission of latent preferences for residential location and vehicle ownership from the analysis can lead to biased results; previous studies may have overestimated the complementarity or substitution relationships between public transit and ridehailing by ignoring confounding effects; and even after accounting for other effects, individuals living in vibrant and walkable neighborhoods have a higher mode share for ridehailing (potentially using it instead of active modes).     

IAATO's stewardship of the antarctic environment: a history of tour operator's concern for a vulnerable part of the world

After a relatively slow start in the 1950s and 1960s, shipborne tourism in Antarctica has become a regular activity, with about 89 000 visitors to date (through the 1997–1998 austral summer). Recognising the need for standardisation of operating procedures that would protect the vulnerable environment, tour operators initiated codes of conduct in the 1980s. In 1991 the existing seven tour operators formed the International Association of Antarctica Tour Operators (IAATO), the objective being to act as a single voice to advocate, promote and practice safe and environmentally responsible private‐sector travel in Antarctica. Since then, Antarctic Treaty Parties passed Recommendation XVIII‐1 in 1994, expanding the operator's guidelines into a comparable and formal version. Associated with that, a Protocol on Environmental Protection to the Antarctic Treaty has become effective, initiating formal application and permitting requirements that affect both tourism and scientific activities. The implications of the Protocol on the tourism industry are discussed and analysed. Copyright © 2000 John Wiley & Sons, Ltd.     

A case study of flexible solutions to transport demand in a deregulated environment

Since public transport deregulation in the UK the provision of solutions to transport demand in areas of dispersed demand has been met by local authorities’ attempts to “fill gaps” in the commercial public transport network, whilst the voluntary sector has addressed the needs of more specialised travel. Over the last five years more innovative solutions have been enabled by the development of Intelligent Transport Systems (ITS), which allow more flexible transport services in terms of time and space. In addition, new ways of thinking about the provision of what might be considered public transport has led to more flexible transport modes becoming available, permitting the general public on education contract services, the use of taxis for shared public transport and the provision of vehicles enabling access to work. However, these innovations tend to operate independently leading to overlap, gaps and misunderstandings about the purpose, delivery and receipt of services. To address these issues, future public transport services will need wider area network planning, greater co-operation between service providers (e.g. in the form of partnerships) and improved understanding of passenger requirements. The case study of Northumberland presented in this paper embodies many of the problems faced by residents in rural areas of the UK to-day and illustrates diverse solutions that have been made to address these challenges.