Modelling bicycle use intention: the role of perceptions

Users’ perceptions are identified as key elements to understand bicycle use, whose election cannot be explained with usual mobility variables and socio-economic characteristics. A hybrid model is proposed to model the intention of bicycle use; it combines a structural equations model that captures intentions and a choice model. The framework is applied to a case of a university campus in Madrid that is studying a new internal bike system. Results show that four latent variables (convenience, pro-bike, physical determinants and external restrictions) help explaining intention to use bike, representing a number of factors that are linked to individual perceptions.     

Determinants of the willingness-to-pay for reducing the environmental impacts of road transportation

This paper examines the willingness-to-pay of people living in a number of villages in Navarre, in the Spanish Pyrenees to reduce noise and air pollution. Several models are used for estimation based on contingent valuation, noting that those living near roads are willing to pay more to reduce air and noise pollution. In addition, younger people, the better educated, and the more environmentally aware individuals are also willing to pay more to reduce those externalities.     

沥青混合料骨架结构抗剪强度特性的试验研究

采用悬浮密实结构AC-20I、骨架空隙结构AM-20及骨架密实结构SMA-20试样,对三种典型结构的沥青混合料抗剪强度进行了对比试验研究.试验采用粗骨料大型直剪仪,探讨了球形和椭球形集料对抗剪强度的影响.结果表明:从集料级配看,骨架结构形成的抗剪强度明显大于悬浮结构形成的抗剪强度;从集料形状看,椭球体集料构成结构的内摩擦角大于球形体集料构成结构的内摩擦角,而且,骨架密实结构对集料形状最为敏感.     

莫桑比克沥青路面设计介绍

沥青混凝土因其具有初始投资低、易于维修和循环使用等优点,广泛应用于世界各地,在南非和莫桑比克的路面结构中也得到广泛采用。文章介绍了莫桑比克使用的沥青混凝土设计方法(基于SATCC方法),以期与国内设计方法进行对比研究。     

Cross-sector Analysis of Four Renegotiated Transport PPPs in Portugal

Abstract

This paper uses the Fertagus renegotiation results as a reference and explores the features that made it such a widely commended case, aiming to identify the best practice to be followed in other cases. The two main questions that this paper aimed to respond were: Was the success of the renegotiation process in the Fertagus contract due to mode-specific factors? Are those factors (mode specific or not) transferable to other modes under public private partnership (PPP) contracts and if so, to what extent? Regarding the mode specificity and transferability analysis, it can be noticed that much of the features were not mode specific in theory, however for the successful transferability to other transport modes, some changes should be made to the PPP model taking into account modal specificities and national contexts.     

Using best–worst scaling to identify barriers to walkability: a study of Porto Alegre,Brazil

This paper pursues three goals: (1) determining the relative importance of built environment barriers limiting walkability, (2) analyzing the existence of an asymmetry in the way people evaluate positive and negative built environment characteristics, and (3) identifying solutions to tackle the main barriers and quantify their impact in walkability. A best–worst scaling survey was developed to compare the importance of eight different attributes of the built environment regarding walkability. Model results show an asymmetry negative–positive in the judgment and choice of built environment characteristics that promote and impede walkability. The most important barriers, obtained from worst responses, are connectivity, topography, sidewalk surface and absence of policemen. Walkability scores were computed for different neighbourhoods and different policy scenarios were forecasted. Simulation results from the worst responses indicate that improvements in sidewalk quality, along with an increase in the number of police officers, lead to an 85% increase in the walkability score for the lower income neighbourhoods.

     

Advancing Knowledge for Use in Coastal and Estuarine Management: Competitive Research in the National Estuarine Research Reserve System

Decades of research has generated new scientific understanding and technologies aimed at better managing environmental change in estuarine and coastal regions. Yet many across the communities of coastal and estuarine research, management, and funding believe that progress has been too slow in applying this research in practice. This essay reviews how the National Estuarine Research Reserve System’s funding program evolved over the past two decades to improve how researchers and users of research work together to increase the uptake of science to achieve resource management and conservation goals. Incremental innovation in the design of the NERRS funding program enabled more intensive and multiway engagement between funders, researchers, and users, which created new pathways for applying science in practice. Furthermore, these interactions stimulate reflection and adaptation within each separate institutional setting, supporting changes that may science to better support environmental problem solving.     

Employment status and commute distance of Canadians with disabilities

Alleviating the disability challenges experienced by people with impairments is increasingly seen as an important step towards building more inclusive societies. The very definition of disability has evolved to shift the burden from people with impairments to perform at “normal” competency levels and towards a fuller recognition of the ways that society can either build or tear down barriers that hinder their full participation in society. The objective of this paper is to investigate the factors that act as facilitators or barriers to participation by people with impairments. Specifically, the study is conducted within the context of employment status and commute distance, two outcomes indicative of the ability of individuals with impairments to engage society. Analysis is based on Canada’s 2006 Participation and Activity Limitation Survey, a post-censal survey that collects information on various aspects of disabilities for a representative sample of Canadian society. The results, based on a probit model for employment status and a regression model for commute distance, provide insights into the personal, economic, and living space factors that affect the probability of being employed and traveling longer distances.     

Modelling passengers,buses and stops in traffic microsimulation: review and extensions

In the last decade, significant research efforts and technology have been dedicated to the development of microsimulation tools for a better representation of traffic systems. As a result, several commercial packages appeared and they are used nowadays in the detailed modelling of different transportation systems and operations for specific project evaluations and local designs, mostly within the urban context. After reviewing the specialized literature, we realized that most of these microsimulation tools are oriented to the movement of cars, leaving the public transportation systems as a complement, just for a realistic representation of the transportation system as a whole, but always oriented to simulate cars. In this paper, the objective is to provide guidelines on how to incorporate the necessary entities and components for a proper simulation of public transport systems in a microsimulation environment. Thus, the different approaches to simulate transit systems at a microlevel are discussed, highlighting the necessity of including stops, passengers and transit vehicles explicitly as entities within the microsimulation environment, for modelling transfer operations, control strategies, etc. Several examples are then provided to quantify the impact of such representations, for different cases and potential simulation platforms. Copyright © 2010 John Wiley & Sons, Ltd.