Showing papers by "Margaret Bell published in 2014"

Understanding the characteristics of the microenvironments in urban street canyons through analysis of pollution measured using a novel pervasive sensor array

Abstract: This paper presents results of comprehensive analyses of data from the first 122 commercially available wireless environmental pervasive sensors (motes), developed by Newcastle University and deployed in England. Measurements of pollution, meteorology and traffic are used to investigate the complexity of the physical and chemical processes governing the levels of traffic-related pollution in urban areas. Following a brief introduction on health impacts associated with air quality, description of the mote technology is given. Cluster analysis statistics to investigate the relationship between different pollutant types and traffic data demonstrated that traffic flow regimes alone cannot be used to estimate diurnal kerbside pollutant concentrations. Also, the absolute levels, whilst dependent on meteorological conditions and static parameters are only partially governed by the pollutant dispersion. The research clearly illustrates the benefits and added value of pervasive concentration measurement in urban micro environments with potential to effectively evaluate human exposure to transport-related emissions.

Quantifying a cellular automata simulation of electric vehicles

Abstract: Within this work the Nagel–Schreckenberg (NS) cellular automata is used to simulate a basic cyclic road network. Results from SwitchEV, a real world Electric Vehicle trial which has collected more than two years of detailed electric vehicle data, are used to quantify the results of the NS automata, demonstrating similar power consumption behavior to that observed in the experimental results. In particular the efficiency of the electric vehicles reduces as the vehicle density increases, due in part to the reduced efficiency of EVs at low speeds, but also due to the energy consumption inherent in changing speeds. Further work shows the results from introducing spatially restricted speed restriction. In general it can be seen that induced congestion from spatially transient events propagates back through the road network and alters the energy and efficiency profile of the simulated vehicles, both before and after the speed restriction. Vehicles upstream from the restriction show a reduced energy usage and an increased efficiency, and vehicles downstream show an initial large increase in energy usage as they accelerate away from the speed restriction.

Processes to manage analyses and publications in a phase III multicenter randomized clinical trial

Abstract: Background: The timely publication of findings in peer-reviewed journals is a primary goal of clinical research. In clinical trials, the processes leading to publication can be complex from choice and prioritization of analytic topics through to journal submission and revisions. As little literature exists on the publication process for multicenter trials, we describe the development, implementation, and effectiveness of such a process in a multicenter trial. Methods: The Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) trial included a data coordinating center (DCC) and clinical centers that recruited and followed more than 1,000 patients. Publication guidelines were approved by the steering committee, and the publications committee monitored the publication process from selection of topics to publication. Results: A total of 73 manuscripts were published in 23 peer-reviewed journals. When manuscripts were closely tracked, the median time for analyses and drafting of manuscripts was 8 months. The median time for data analyses was 5 months and the median time for manuscript drafting was 3 months. The median time for publications committee review, submission, and journal acceptance was 7 months, and the median time from analytic start to journal acceptance was 18 months. Conclusions: Effective publication guidelines must be comprehensive, implemented early in a trial, and require active management by study investigators. Successful collaboration, such as in the HALT-C trial, can serve as a model for others involved in multidisciplinary and multicenter research programs. Trial registration: The HALT-C Trial was registered with clinicaltrials.gov (NCT00006164).

A congestion sensitive approach to modelling road networks for air quality management

Abstract: This research establishes an approach to modelling a congested road network for air quality management, which enables the assessment of traffic management solutions that may create only subtle changes in the traffic flow regimes. Road network emissions have been calculated using standard factors taking into account details of vehicle fleet composition, average speeds and road type. Additionally, the use of microsimulation traffic modelling in conjunction with an instantaneous emissions model (IEM) has been adopted to allow comparison between methodologies and enable congestion sensitive analysis of the impact of air quality management measures on the network. Findings from microscale modelling have revealed that the use of an IEM to calculate emissions as an input for air quality dispersion modelling significantly improved the performance of the dispersion modelling when measured against monitored data. Moreover, this methodology has been successfully applied to assess the performance of a traffic scheme in Durham, UK.

Autonomic Decision Support System for Traffic and Environment Management

Abstract: Outdoor air pollution causes approximately 1.3 million deaths every year worldwide and approximately 310,000 premature deaths in Europe as revealed by the Department of Business, Innovation and Skills. Given road traffic and more specifically congestion is a major source of pollution, there is an urgent need to apply network management aimed at delivering air quality as well as carbon targets. Intelligent Transport Systems can be used for traffic management application and as a by-product of their control produce huge volumes of data that are useful to support traffic operators in their decision-making. Due to the increasing amount of available ITS, traffic operators are faced with an increasing amount of information overload. More sophistication is needed to achieve multiple policy objectives and across modes of transport. Autonomic computing is a software environment with the ability of self-management and dynamic adaption in relation to business policies and objectives alternatively defined as automation of system adaptation. Autonomic computing is a technology that comes into play where there is need to minimise cost and maximise efficiency through management of resources and applications. Following an overview of the policy context, this paper presents an autonomic system and demonstrates self- optimization of lane choice on a UK motorway and a Dutch trunk road through a case study. By creating an autonomic capability which can reason within the data analysis layer of a data platform, traffic control networks can begin to manage more effectively routine control decisions from day to day and as a next step against multiple objectives and thus free up engineers time to devote to the more complex tasks.

Importance-satisfaction analysis of rail services in the uk with respect totravel time use

Abstract: The availability of information and communication technology such as Wi-Fi and electric socket on-board is expected to change consumer attitude and behaviour toward rail services as time spent travelling could be more productive and enjoyable. However, do the availability of Wi-Fi and electric power socket on-board were more importance than other performance attributes in consumers’ perception? This paper presents the result of an importance-satisfaction analysis of several attributes of train services in the UK. The study found that ticket price; reliability and seating guarantee were more importance than other attributes whilst Wi-Fi and electric socket were less importance. The results indicated that travel time use is just a complementary of the main objective of travel, which is to arrive at the destination.