Advanced reliability analysis of Polymer Electrolyte Membrane Fuel Cells using Petri-Net analysis and fuel cell modelling techniques

This is the author’s version of a work that was accepted for publication in International Journal of Hydrogen Energy. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published at: http://dx.doi.org/10.1016/j.ijhydene.2015.01.154Reliability issues with fuel cells have held back the commercialisation of this new technology, and as such are required to be studied further. Current reliability standards for automotive applications require an operational life- time of 150,000 miles or 5,000 hours. These standards are hard to achieve; therefore in depth reliability analysis and degradation studies can help allude towards the key areas of improvement in fuel cell technology to meet these standards. Previous Failure Mode and Effect Analysis (FMEA) work has shown that the multi-component system of a Polymer Electrolyte Membrane Fuel Cell (PEMFC) is inherently complex. Dependencies exist between multiple failure modes which discounts Fault Tree Analysis (FTA) as a feasible reliability modelling technique. Therefore, in this study, Petri-Net simulation and fuel cell modelling techniques have been adopted to develop an accurate degradation model. Operational parameters such as water content, temperature and current density and their effects on the occurrence of failure modes can be modelled through this technique. The work will improve previous fuel cell reliability studies by taking into consideration; operating parameters (water content, temperature), fuel cell voltage based on demand (drive cycles) and dependencies between failure modes

Life after Regions? The Evolution of City-regionalism in England

This item was accepted for publication in the journal, Regional Studies [© Regional Studies Association]. The definitive version is available at http://dx.doi.org/10.1080/00343404.2010.521148].This paper examines the evolving pattern of city-regional governance in England. Following the demise of English regional policy in 2004, city-regions have come to represent the in vogue spatial scale amongst policy elites. The result has been a proliferation of actual and proposed policies and institutions designed to operate at a, variously defined, city-regional scale in England. Nevertheless, attempts to build a city-regional tier of governance have been tentative and lacking coherence. Alongside this city-regions are to be found emerging alongside existing tiers of economic governance and spatial planning. Arguing that what we are witnessing is not ‘life after regions’ but life with (or alongside) regions, the analysis presented argues that to understand why contemporary state reorganisation results in a multiplication of the scales economic governance and spatial planning we must recognise how the state shapes policies in such a way as to protect its legitimacy for maintain regulatory control and management of the economy. The final section relates these findings to wider debates on state rescaling and speculates on the future role of transition models in sociospatial theory

Classification of beach response to extreme storms

publisher: Elsevier articletitle: Classification of beach response to extreme storms journaltitle: Geomorphology articlelink: http://dx.doi.org/10.1016/j.geomorph.2017.07.022 content_type: article copyright: Crown Copyright © 2017 Published by Elsevier B.V

Discourse, justification and critique: towards a legitimate digital copyright regime?

Digitization and the internet have posed an acute economic challenge to rights holders in the cultural industries. Faced with a threat to their form of capital accumulation from copyright infringement, rights holders have used discourse strategically in order to try and legitimate and strengthen their position in the digital copyright debate with governments and media users. In so doing, they have appealed to general justificatory principles – about what is good, right, and just – that provide some scope for opposition and critique, as other groups contest their interpretation of these principles and the evidence used to support them. In this article, we address the relative lack of academic attention paid to the role of discourse in copyright debates by analysing user-directed marketing campaigns and submissions to UK government policy consultations. We show how legitimacy claims are justified and critiqued, and conclude that amid these debates rests some hope of achieving a more legitimate policy resolution to the copyright wars – or at least the possibility of beginning a more constructive dialogue

Configuring the New ‘Regional World’: On being Caught between Territory and Networks

This article was accepted for publication in the journal, Regional Studies [© Taylor & Francis].Recent years have witnessed a tremendous appeal in debating the relative decline in ‘territorially embedded’ conceptions of regions vis-à-vis the privileging of ‘relational and unbounded’ conceptions. Nevertheless, the most recent skirmishes see some scholars emphasise how it is not the privileging of one or other that is important, but recognising how it is increasingly different combinations of these elements that seem to be emerging in today’s new ‘regional world’. Here emphasis is being placed on a need to analyse how the different dimensions of socio-spatial relations (e.g. territory, place, network, scale) come together in different ways, at different times, and in different contexts to secure the overall coherence of capitalist, and other, social formations. The purpose of this paper is to make visible the politics of transformation in North West England, uncovering the role and strategies of individual and collective agents, organisations and institutions in orchestrating and steering regional economic development. For it is argued the unanswered question is not which sociospatial relations are dominant, emerging, or residual in any given space-time but understanding how and why they are dominant, emerging, or residual. The paper suggests the answer to this and other questions is to be found at the interface between emergent spatial strategies and inherited sociospatial configurations

Policy making under uncertainty in electric vehicle demand

The introduction of electric vehicles (EVs) into the passenger vehicle market has, in recent years, become viewed as a primary solution to the significant carbon dioxide emissions attributed to personal mobility. Moreover, EVs offer a means by which energy diversification and efficiency can be improved compared to the current system. The UK government and European Commission have played an active role in steering the development and market introduction of EVs. However, a great deal of uncertainty remains regarding the effectiveness of these policies and the viability of EV technology in the mainstream automotive market. This paper investigates the prevalence of uncertainty concerning the demand for EVs. This is achieved through the application of a conceptual framework that assesses the locations of uncertainty. UK and EU documents are assessed through a review of the published policy alongside contributions from academia to determine how uncertainty has been reduced. This assessment offers insights to decision makers in this area by evaluating the work done to date through a landscape analysis. Results have identified six different locations of uncertainty covering: consumer, policy, infrastructure, technical, economic and social issues