6 resultados para Swash zone sediment transport
em WestminsterResearch - UK
Resumo:
London’s air quality has improved over recent decades, but is still the worst in the UK. Road transport emissions play an important part in this pollution. A low emission zone (LEZ) would help to accelerate the introduction of cleaner vehicles, and reduce the numbers of older, more polluting vehicles operating in London. The survey work carried out indicates that there is support among goods vehicle operators for an LEZ in London, depending on the precise scheme definition. Operators would generally try to comply with LEZ regulations, with most companies either using technical approaches to ensure that their London vehicle fleet complied with the required emission standard or by redeploying vehicles with the appropriate emission standard from other locations.
Resumo:
London's air quality has improved over recent decades, but is still the worst in the UK. Road transport emissions play an important part in this pollution. A low emission zone (LEZ) would help to accelerate the introduction of cleaner vehicles, and reduce the number of older, more polluting vehicles operating in London. Survey results indicate that there is some support among goods vehicle operators for a LEZ in London, depending on the precise scheme definition. Operators would generally try to comply with LEZ regulations, with most companies either using technical approaches to ensure that their London vehicle fleet complied with the required emission standard, or redeploying vehicles with the appropriate emission standard from other locations.
Resumo:
This paper assesses whether two sustainability policies currently in effect in London, a congestion charge zone and a low emission zone, have affected freight operations and reduced vehicle kilometers travelled. It investigates responses by freight operators, including re-timing, re-routing, or reducing the number of trips, or replacing vehicles. Freight traffic trends from 1994 to 2012 were identified using road traffic estimates, cordon counts, and vehicle speed data and supplemented by interviews with freight industry experts and operators. Findings indicate that freight traffic increased throughout London during this timeframe, but declined in the central boroughs partly within the congestion charge zone. The congestion charge may have time-shifted some light goods trips, but most freight trips face a variety of constraints on operators’ delivery window. No evidence was found of re-routing of freight traffic or avoidance traffic around the charged zone. The low emission zone spurred higher levels of operational change than the congestion charge zone, and it was effective at spurring freight vehicle replacement. The paper also discusses freight operators’ perceptions of these policies and how they could be improved.
Resumo:
The paper presents the ‘Marginal Activity Access Cost’, an accessibility indicator providing estimation in monetary terms of the impacts on mobility and on the environment of locating a single new activity in a specific zone of the urban area. In the first part of this paper, the new indicator is presented and compared to other accessibility indicators proposed in literature. In the second part, the MAAC is validated through an application to the urban area of Rome. The paper concludes with brief remarks on using the proposed accessibility indicator as index of performance for sustainable spatial planning.
Resumo:
The paper fits into the themes of sustainable accessibility planning in urban areas, that can be defined as the integration of transport and land use planning to achieve sustainable development. In particular the study proposes a tool to support the choices of activities location, which is based on a new aggregate (zone-specific) indicator: the ‘Marginal Activity Access Cost’, providing estimation in monetary terms of the impacts on mobility and on the environment of locating one new activity in a specific zone of the urban area. The proposed indicator is validated through an application to the urban area of Rome.