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Defining the architecture and attributes of successful climate change adaptation surrounding long-lived infrastructure in the coastal zoneArmstrong, Jennifer C. January 2017 (has links)
Climate variability and change threaten human and physical systems in coastal zones. With more than 10% of the global population now living and working in low elevation coastal zones, successful adaptation to climate change is becoming a pressing issue, particularly for areas featuring critical, long-lived infrastructure. The aim of this research is to define the architecture and attributes contributing to successful adaptation to climate change. Here, success is measured in terms of the process rather than outcomes of adaptation initiatives. The research features two empirical phases: adaptation framework analysis and an evaluation of factors affecting the adaptive capacity of stakeholder organisations. Framework analysis involved the development of a criterion tool based on recurrent features of different adaptation frameworks as described in research literature. Six hallmarks emerged as discriminators of Scenario-Led (SL), Vulnerability-Led (VL) and Decision-Centric (DC) frameworks. The criterion tool was then tested using four UK coastal case study areas, drawing on evidence from public domain adaptation documents. The Grounded Theory Methodology (GTM) was used investigate factors enabling or inhibiting stakeholder adaptation efforts by designing and iteratively adjust semi-structured interviews with stakeholder organisations in the Sizewell nuclear neighbourhood, Suffolk, UK. The findings from the two phases were brought together to identify opportunities to improve the adaptation processes. Analysis of the adaptation architecture revealed that stakeholders rarely use one theoretical adaptation approach. A hybrid adaptation framework is adopted, with the DC/SL or DC/VL being utilised most frequently. Findings reveal a mismatch between theoretical frameworks and those implemented in practise. Semi-structured interviews exposed six key themes defining adaptation process. Stakeholder organisations reported 12 factors that affect their standpoints on each key theme. Standpoints were broadly consistent between similar stakeholder organisations. Stakeholder groups, key themes and influencing factors provide an evidence base for evaluating the complex social dynamics affecting successes of the adaptation process, offering a route to pragmatic adaptation guidance. By considering the architecture and attributes of adaptation coastal stakeholders in neighbourhoods with long-lived infrastructure could strengthen the adaptation process, thereby realising their shared vision(s) of integrated coastal management. There is scope for improving and advancing the research. It is acknowledged that the inventories of adaptation initiatives were uneven in size and scope, potentially limiting the evaluation of the criterion tool. This may be addressed by assessing other coastal neighbourhoods with long-lived infrastructure. When interviewing representatives from stakeholder organisations, it was difficult to differentiate between personal or professional views. Future research could investigate how the role of the individual influences adaptation efforts. Insights could further refine the architecture and attributes of adaptation.
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Fracture properties of Soft Materials : From Linear Elastic Fracture to damage at the microscopic scale / Rupture de matériaux mous : De l’élasticité linéaire à l’endommagement aux échelles microscopiquesLefranc, Maxime 19 February 2015 (has links)
Notre nouvelle approche expérimentale consiste à étudier la fissuration de matériaux mous, principalement des gels polymériques et colloidaux, qui ont des tailles microstructurales micrométriques. Cette augmentation de la taille microscopique va avoir pour conséquence d’augmenter la taille de la zone de process et va rendre son observation plus facile avec des moyens standard de microscopie (à transmission et confocale).Pour se faire, nous avons mis au point un nouveau dispositif expérimental pour étudier la propagation de fissures dans des matériaux mous. Cette expérience permet de faire croître une fissure de manière contrôlée dans un échantillon mou et d’inspecter la pointe de fissure à haute résolution pour des fissures se propageant entre 1 µm/s and 1cm/s. En travaillant avec des gels de polymère physiques, nous avons analyse la forme de fissure ainsi que les champs de déplacement proches pointe (en utilisant des techniques de corrélation d’image) à petites et grandes échelles et à différentes vitesses. Nous avons montré qu’il existait une séparation d’échelles spatiales entre les échelles où l’élasticité linéaire s’applique, les échelles auxquelles les non linéarités émergent et les échelles auxquelles la dissipation se produit. Cette dernière échelle n’a pas pu être investigué dans le cas de gels polymériques. De récentes expériences sur des gels colloïdaux, ayant une longueur micro-structurale plus grande que celle des gels polymers, montre que nous sommes capables de sonder en temps réel les échelles d’endommagement lors de la fissuration. / Our novel experimental approach consists in studying fracture mechanics of soft materials, mainly polymer and colloidal gels, which have microstructures with large typical length scales. This increase in the microscopic length scale will consequently increase the typical size of the process zone and make its observation easier with standard microscopy techniques (optical or confocal).To do so, we designed a novel experimental device to study crack propagation in such soft materials. This experiment enables us to grow a unique crack in a controlled way in a soft specimen and to look at the crack tip at high magnification for crack velocities between 1 µm/s and 1cm/s. Working on physical polymer gels, we analysed the crack shape and crack displacement fields (using Digital Image Correlation) at large and intermediate scales for various velocities. We realized there was a separation of scales between the scale at which LEFM applies, the scale at which elastic nonlinearities emerge and the scale at which dissipation occurs. This last scale could not be investigated with the polymer gel. Recent experiments on colloidal gels, which have a microscopic length scale bigger than the one of polymer gels, show that we are able to probe damage at the microstructural scale.
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