Abstract

In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent, the urban heat island (UHI) area and intensity will increase compared with the current situation, continuous heat islands may occur in local areas, the UHI potential index of the core area will rise from 0.0878 to 0.1217 (still a favorable level). Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh, cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources.

Abstract

Complexity science is the multidisciplinary study of complex systems. Its marked network orientation lends itself well to transport contexts. Key features of complexity science are introduced and defined, with a specific focus on the application to air traffic management. An overview of complex network theory is presented, with examples of its corresponding metrics and multiple scales. Complexity science is starting to make important contributions to performance assessment and system design: selected, applied air traffic management case studies are explored. The important contexts of uncertainty, resilience and emergent behaviour are discussed, with future research priorities summarised.

Abstract

America’s roadways are becoming more congested and more in need of maintenance and repair, management of traffic through work zones is a major issue for state departments of transportation. To aid this, in 2004, the Federal Highway Administration (FHWA) published its Final Rule on Work Zone Safety and Mobility, which mandated that state DOTs develop transportation management plans (TMPs) for all federally-funded roadway construction projects. The Virginia Department of Transportation (VDOT) now requires TMPs for all projects, regardless of funding source. Part of federal and Virginia TMP requirements are to monitor and assess traffic impacts, including a post-construction evaluation of the TMP. Currently, TMPs are not being assessed following individual construction projects, and VDOT does not yet have a formally established process to assess TMP performance throughout its districts and regions. This project developed a set of guidelines to assist VDOT’s work zone personnel and contractors with evaluating TMP performance. The research examines existing literature on work zone evaluation strategies. Thirty state DOTs, as well as personnel within VDOT, were surveyed to explore TMP assessment practices. Finally, two work zone case studies from within the Commonwealth of Virginia were examined. The results of this research effort were used to develop Guidelines for TMP Performance Assessment, with aid and review from a VDOT TMP Performance Assessment Task Group. While these new requirements may add up-front costs to project engineering, VDOT will benefit by having a methodology in place to identify and measure successful strategies to manage safety and mobility impacts from work zones.

Abstract

it is considerably difficult to identify specific changes by using a single numeric parameter, improvements gained by a new urban public transport (UPT) facility or by an operation policy is still a challenge in the decision-making process with respect to transportation planning. Although some indicators such as service quality, capacity usage ratio, service kilometers, passenger kilometers or seat kilometers are used by planners and policy makers, these indicators may not always reflect the total gain of trip makers: to access a facility providing a specific utility. Thus, this study aims to evaluate accessibility measures as performance indicators in the UPT planning process. Three scenarios that consist of timetable regulation, central business district restriction and integration with bus rapid transit are investigated using accessibility perspective in addition to the conventional indicators obtained by using VISUM™ travel demand modeling software. The results show that the first scenario leads to a more effective UPT system in terms of accessibility. Hence, a more distinctive measure is obtained for the decision stage of UPT planning. © 2013 Elsevier Ltd.