72 resultados para Process Development

em CentAUR: Central Archive University of Reading - UK


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Biaxially oriented films produced from semi-crystalline, semi-aromatic polyesters are utilised extensively as components within various applications, including the specialist packaging, flexible electronic and photovoltaic markets. However, the thermal performance of such polyesters, specifically poly(ethylene terephthalate) (PET) and poly(ethylene-2,6-naphthalate) (PEN), is inadequate for several applications that require greater dimensional stability at higher operating temperatures. The work described in this project is therefore primarily focussed upon the copolymerisation of rigid comonomers with PET and PEN, in order to produce novel polyester-based materials that exhibit superior thermomechanical performance, with retention of crystallinity, to achieve biaxial orientation. Rigid biphenyldiimide comonomers were readily incorporated into PEN and poly(butylene-2,6-naphthalate) (PBN) via a melt-polycondensation route. For each copoly(ester-imide) series, retention of semi-crystalline behaviour is observed throughout entire copolymer composition ratios. This phenomenon may be rationalised by cocrystallisation between isomorphic biphenyldiimide and naphthalenedicarboxylate residues, which enables statistically random copolymers to melt-crystallise despite high proportions of imide sub-units being present. In terms of thermal performance, the glass transition temperature, Tg, linearly increases with imide comonomer content for both series. This facilitated the production of several high performance PEN-based biaxially oriented films, which displayed analogous drawing, barrier and optical properties to PEN. Selected PBN copoly(ester-imide)s also possess the ability to either melt-crystallise, or form a mesophase from the isotropic state depending on the applied cooling rate. An equivalent synthetic approach based upon isomorphic comonomer crystallisation was subsequently applied to PET by copolymerisation with rigid diimide and Kevlar®-type amide comonomers, to afford several novel high performance PET-based copoly(ester-imide)s and copoly(ester-amide)s that all exhibited increased Tgs. Retention of crystallinity was achieved in these copolymers by either melt-crystallisation or thermal annealing. The initial production of a semi-crystalline, PET-based biaxially oriented film with a Tg in excess of 100 °C was successful, and this material has obvious scope for further industrial scale-up and process development.

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Partnerships are complex, diverse and subtle relationships, the nature of which changes with time, but they are vital for the functioning of the development chain. This paper reviews the meaning of partnership between development institutions as well as some of the main approaches taken to analyse the relationships. The latter typically revolve around analyses based on power, discourse, interdependence and functionality. The paper makes the case for taking a multianalytical approach to understanding partnership but points out three problem areas: identifying acceptable/unacceptable trade-offs between characteristics of partnership, the analysis of multicomponent partnerships (where one partner has a number of other partners) and the analysis of long-term partnership. The latter is especially problematic for long-term partnerships between donors and field agencies that share an underlying commitment based on religious beliefs. These problems with current methods of analysing partnership are highlighted by focusing upon the Catholic Church-based development chain, linking donors in the North (Europe) and their field partners in the South (Abuja Ecclesiastical Province, Nigeria). It explores a narrated history of a relationship with a single donor spanning 35 years from the perspective of one partner (the field agency).

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There is a lack of knowledge base in relation to experiences gained and lessons learnt from previously executed National Health Service (NHS) infrastructure projects in the UK. This is in part a feature of one-off construction projects, which typify healthcare infrastructure, and in part due to the absence of a suitable method for conveying such information. The complexity of infrastructure delivery process in the NHS makes the construction of healthcare buildings a formidable task. This is particularly the case for the NHS trusts who have little or no experience of construction projects. To facilitate understanding a most important aspect of the delivery process, which is the preparation of a capital investment proposal; steps taken in developing the business case for an NHS healthcare facility are examined. The context for such examination is provided by the planning process of a healthcare project, studied retrospectively. The process is analysed using a social science based method called ‘building stories’, developed at the University of California-Berkeley. By applying this method, stories or narratives are constructed around the data captured on the case study. The findings indicate that the business case process may be used to justify, rather than identify, trusts’ requirements. The study is useful for UK public sector clients as well as consultants and professionals who aim to participate in the delivery of healthcare infrastructure projects in the UK.

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Synthesis of prebiotic alpha- and beta-galactooligosaccharides (GOS) using the whole cells of Bifidobacterium bifidum NCIMB 41171 was investigated. Determination of alpha- and beta-galactosidase activities showed them to be at 3 and 205 g(-1) of freeze dried biomass, respectively, and they increased to 5 and 344 U g(-1), respectively, when cells were treated with toluene. Starting with 450-500 mg mL(-1) lactose, maximum GOS concentrations were observed at 80-85% lactose conversions and the mixtures contained oligosaccharides (with a degree of polymerisation >= 3) at 77-109 mg mL(-1) and trans-galactosylated disaccharides between 85-115 mg mL(-1). The GOS yield values varied between 36% and 43%. An alpha-linked disaccharide was detected and its presence was confirmed by gas chromatography mass spectroscopy. Cells were re-used up to 8 times without changes in reaction times or the substrate conversions to GOS. Oligosaccharide synthesis was not inhibited by the presence of glucose or galactose. The mixtures were successfully purified from glucose (92% of glucose removed) by fermentation with Saccharomyces cerevisiae with no losses in the oligosaccharide content and only a small decrease on the galactose. (c) 2006 Elsevier Ltd. All rights reserved.

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Over the last decade issues related to the financial viability of development have become increasingly important to the English planning system. As part of a wider shift towards the compartmentalisation of planning tasks, expert consultants are required to quantify, in an attempt to rationalise, planning decisions in terms of economic ‘viability’. Often with a particular focus on planning obligations, the results of development viability modelling have emerged as a key part of the evidence base used in site-specific negotiations and in planning policy formation. Focussing on the role of clients and other stakeholders, this paper investigates how development viability is tested in practice. It draws together literature on the role of calculative practices in policy formation, client feedback and influence in real estate appraisals and stakeholder engagement and consultation in the planning literature to critically evaluate the role of clients and other interest groups in influencing the production and use of development viability appraisal models. The paper draws upon semi-structured interviews with the main producers of development viability appraisals to conclude that, whilst appraisals have the potential to be biased by client and stakeholder interests, there are important controlling influences on potential opportunistic behaviour. One such control is local authorities’ weak understanding of development viability appraisal techniques which limits their capacity to question the outputs of appraisal models. However, this also is of concern given that viability is now a central feature of the town planning system.

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A combination of in situ and ex situ X-ray scattering techniques and transmission electron microscopy has been used to study the crystallization behaviour of polyethylene, following the imposition of melt shear. In the case of a branched material, the imposition of shear flow up to a rate of 30 s(-1) was found to induce no anisotropy. Although shearing the linear material only ever induced a very small degree of anisotropy in the melt, for shear rates > 0.15 s(-1), subsequent crystallization resulted in increasing anisotropy. Blends of the above two polyethylenes were produced, in which the linear material constituted the minority fraction (similar to 10%). Isothermal crystallization at temperatures where extensive crystallization of the branched material does not occur demonstrated that the behaviour of the linear component of the sheared blend mirrored that of the linear polyethylene alone. However, in addition, it was found that when crystallized in the presence of an oriented morphology, the branched polymer also formed anisotropic structures. We have termed the process templating, in which the crystallization behaviour of the bulk of the system (similar to 90% branched material) is completely altered (spherulitic to oriented lamellar) by mapping it onto a pre-existing minority structure (similar to 10% linear polymer). (c) 2006 Elsevier Ltd. All rights reserved.

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This paper constitutes an attempt to find a means to represent multiple stories in the strong narrative of conventional sustainable development (SD) projects. The authors' experience of such projects in various parts of the world indicates that they have a tendency to arise from and reflect a dominant mindset, placing the SD project in what can be a working environment that is inimical to the very ideals that SD is supposed to represent. Short-termism and value for money drive project formats and objectives, whilst counter-narratives and alternative stories arising from stakeholders in such projects are often ignored. Yet these alternative threads often contain strong SD messages of their own and could, if effectively utilized, enhance the SD project process. This paper sets out the case for a new field - 'project ethnography' - allied with the growing use of meta-analysis to compare project 'stories'. The analytical model applied to compare projects is based on the Kolb learning cycle and involves a (3 X 4)-fold questioning of project conceptual ization and roll-out. Copyright @ 2oo6 John Wiley & Sons, Ltd and ERP Environment.

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Problem structuring methods or PSMs are widely applied across a range of variable but generally small-scale organizational contexts. However, it has been argued that they are seen and experienced less often in areas of wide ranging and highly complex human activity-specifically those relating to sustainability, environment, democracy and conflict (or SEDC). In an attempt to plan, track and influence human activity in SEDC contexts, the authors in this paper make the theoretical case for a PSM, derived from various existing approaches. They show how it could make a contribution in a specific practical context-within sustainable coastal development projects around the Mediterranean which have utilized systemic and prospective sustainability analysis or, as it is now known, Imagine. The latter is itself a PSM but one which is 'bounded' within the limits of the project to help deliver the required 'deliverables' set out in the project blueprint. The authors argue that sustainable development projects would benefit from a deconstruction of process by those engaged in the project and suggest one approach that could be taken-a breakout from a project-bounded PSM to an analysis that embraces the project itself. The paper begins with an introduction to the sustainable development context and literature and then goes on to illustrate the issues by grounding the debate within a set of projects facilitated by Blue Plan for Mediterranean coastal zones. The paper goes on to show how the analytical framework could be applied and what insights might be generated.

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This paper reports changes in supraglacial debris cover and supra-/proglacial lake development associated with recent glacier retreat (1985-2000) in the central Caucasus Mountains, Russia. Satellite imagery (Landsat TM and ETM+) was used to map the surface area and supraglacial debris cover on six neighbouring glaciers in the Adylsu valley through a process of manual digitizing on a false-colour composite of bands 5, 4, 3 (red, green, blue). The distribution and surface area of supraglacial and proglacial lakes was digitized for a larger area, which extended to the whole Landsat scene. We also compare our satellite interpretations to field observations in the Adylsu valley. Supraglacial debris cover ranges from < 5% to > 25% on individual glaciers, but glacier retreat between 1985 and 2000 resulted in a 3-6% increase in the proportion of each glacier covered by debris. The only exception to this trend was a very small glacier where debris cover did not change significantly and remote mapping proved more difficult. The increase in debris cover is characterized by a progressive upglacier migration, which we suggest is being driven by focused ablation (and therefore glacier thinning) at the up-glacier limit of the debris cover, resulting in the progressive exposure of englacial debris. Glacier retreat has also been accompanied by an increase in the number of proglacial and supraglacial lakes in our study area, from 16 in 1985 to 24 in 2000, representing a 57% increase in their cumulative surface area. These lakes appear to be impounded by relatively recently lateral and terminal moraines and by debris deposits on the surface of the glacier. The changes in glacier surface characteristics reported here are likely to exert a profound influence on glacier mass balance and their future response to climate change. They may also increase the likelihood of glacier-related hazards (lake outbursts, debris slides), and future monitoring is recommended.

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The ultimate criterion of success for interactive expert systems is that they will be used, and used to effect, by individuals other than the system developers. A key ingredient of success in most systems is involving users in the specification and development of systems as they are being built. However, until recently, system designers have paid little attention to ascertaining user needs and to developing systems with corresponding functionality and appropriate interfaces to match those requirements. Although the situation is beginning to change, many developers do not know how to go about involving users, or else tackle the problem in an inadequate way. This paper discusses the need for user involvement and considers why many developers are still not involving users in an optimal way. It looks at the different ways in which users can be involved in the development process and describes how to select appropriate techniques and methods for studying users. Finally, it discusses some of the problems inherent in involving users in expert system development, and recommends an approach which incorporates both ethnographic analysis and formal user testing.

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From April 2010, the General Pharmaceutical Council (GPhC) will be responsible for the statutory regulation of pharmacists and pharmacy technicians in Great Britain (GB).[1] All statutorily regulated health professionals will need to periodically demonstrate their fitness-to-practise through a process of revalidation.[2] One option being considered in GB is that continuing professional development (CPD) records will form a part of the evidence submitted for revalidation, similar to the system in New Zealand.[3] At present, pharmacy professionals must make a minimum of nine CPD entries per annum from 1 March 2009 using the Royal Pharmaceutical Society of Great Britain (RPSGB) CPD framework. Our aim was to explore the applicability of new revalidation standards within the current CPD framework. We also wanted to review the content of CPD portfolios to assess strengths and qualities and identify any information gaps for the purpose of revalidation.

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An aggregated farm-level index, the Agri-environmental Footprint Index (AFI), based on multiple criteria methods and representing a harmonised approach to evaluation of EU agri-environmental schemes is described. The index uses a common framework for the design and evaluation of policy that can be customised to locally relevant agri-environmental issues and circumstances. Evaluation can be strictly policy-focused, or broader and more holistic in that context-relevant assessment criteria that are not necessarily considered in the evaluated policy can nevertheless be incorporated. The Index structure is flexible, and can respond to diverse local needs. The process of Index construction is interactive, engaging farmers and other relevant stakeholders in a transparent decision-making process that can ensure acceptance of the outcome, help to forge an improved understanding of local agri-environmental priorities and potentially increase awareness of the critical role of farmers in environmental management. The structure of the AFI facilitates post-evaluation analysis of relative performance in different dimensions of the agri-environment, permitting identification of current strengths and weaknesses, and enabling future improvement in policy design. Quantification of the environmental impact of agriculture beyond the stated aims of policy using an 'unweighted' form of the AFI has potential as the basis of an ongoing system of environmental audit within a specified agricultural context. (C) 2009 Elsevier Ltd. All rights reserved.

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This case study on the Sifnos island, Greece, assesses the main factors controlling vegetation succession following crop abandonment and describes the vegetation dynamics of maquis and phrygana formations in relation to alternative theories of secondary succession. Field survey data were collected and analysed at community as well as species level. The results show that vegetation succession on abandoned crop fields is determined by the combined effects of grazing intensity, soil and geological characteristics and time. The analysis determines the quantitative grazing thresholds that modify the successional pathway. Light grazing leads to dominance by maquis vegetation while overgrazing leads to phryganic vegetation. The proposed model shows that vegetation succession following crop abandonment is a complex multi-factor process where the final or the stable stage of the process is not predefined but depends on the factors affecting succession. An example of the use of succession models and disturbance thresholds as a policy assessment tool is presented by evaluating the likely vegetation impacts of the recent reform of the Common Agricultural Policy on Sifnos island over a 20-30-year time horizon. (c) 2006 Elsevier B.V. All rights reserved.