Sur les littoraux de l’Arc Latin, les pressions anthropiques croissantes et les changements climatiques soulèvent de nombreuses interrogations quant à leur devenir. Cette thèse développe des méthodes et connaissances prospectives afin de soutenir l’anticipation requise en termes de prévention et d’adaptation, dans une perspective de durabilité territoriale. Deux axes de recherche sont explorés : une prospective des dynamiques spatiales de littoralisation de l’Arc Latin et une évaluation de l’adaptabilité des territoires littoraux au changement climatique. Ils renvoient à une problématique méthodologique commune, qui est celle de l’évaluation des potentialités d’évolution des territoires littoraux. Interrogeant le rôle des configurations spatiales dans l’évolution des territoires, la posture générale est celle de la prospective spatiale, qui consiste à analyser le devenir des systèmes spatiaux à partir de leur fonctionnement passé et actuel et des propriétés du changement spatial. Des méthodes quantitatives de l’analyse spatiale (ESDA, modélisation par automate cellulaire et dynamique des systèmes) sont combinées avec des méthodes qualitatives (analyse de séquences, analyse de diagrammes causaux) pour intégrer les dynamiques spatio-temporelles et la complexité de l’évolution des territoires. Les résultats de l’analyse des trajectoires de peuplement de l’Arc Latin fournissent une vision d’ensemble et spatialement différenciée de la littoralisation et de ses évolutions potentielles. L’analyse de l’adaptabilité des territoires au changement climatique, réalisée d’une part par des simulations sur des espaces théoriques, et d’autre part par un diagnostic finalisé appliqué à la montée du niveau de la mer en Camargue, montrent l’intérêt de prendre en compte les configurations spatiales pour mettre en évidence des potentialités d’adaptation différenciées et contribuer au choix de mesures d’adaptation en adéquation avec les territoires. / The growing anthropic pressures and the upcoming climatic changes raise many questions about the future of the coasts of the Latin Arc. This thesis develops prospective methods and knowledge in order to support the required anticipation for prevention and adaptation, towards a sustainable territorial development. Two areas of research are explored: a prospective of littoralisation spatial dynamics in the Latin Arc and an assessment of the adaptability of coastal territories to climate change. These two points belong to the same methodological approach, which assesses the evolution potential of coastal territories. Because we question the role of spatial configurations in the evolution of territories, we thus position into the framework of spatial prospective. This field explores the future of spatial systems on the basis of their past and actual functioning and of spatial change properties. Quantitative methods of spatial analysis (ESDA, cellular automata modeling and system dynamics) are combined with qualitative methods (sequence analysis, causal systems analysis). They enable to integrate spatio-temporal dynamics and complexity of the evolution of territories. The results of the population trajectories analysis of the Latin Arc provide anoverall and spatially differentiated vision of littoralisation and of its possible evolutions. The assessment of territories adaptability has been set up by a simulation approach on theoretical spaces on the one hand, and by a diagnosis applied to the rise of sea level in Camargue on the other hand. They show the interest of taking into account spatial configurations to identify differentiated adaptation potentialities and adaptation measures consistent with territories.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 2017 / This study examines the application of the investigation process in industry to reduce electrical arc flash incidents. Literature indicates that three streams (policies, completed investigations and investigators) influence the application of the investigation process; however, these are traditionally analysed independently without examining the dynamic influences between them. This study combines and analyses those dynamic interactions, and testing at a steel plant demonstrates that this approach allows industry to identify site specific deficiencies. The investigation process requirements, identified in literature, were used to qualitatively and quantitatively analyse the three streams. The results were interpreted using triangulation. Deficiencies around disseminating reports and using experienced investigators were identified. These plant specific deficiencies are an improvement from generic findings in literature. This study contributed to knowledge in the field of incident investigations by proposing a holistic approach that is operationally ready, and identifies deficiencies specific to the industry in which it is used. / MT 2018

Who was Joan of Arc? That was the first question in my mind before I began my journey of studying this remarkable young woman. I had no idea how special she was. I thought she was just another historical figure that gets lost in history books. All I really knew about her was that she was burned at the stake. What I didn't know was that she led a country's army into battle at the age of seventeen.The adaptation of Mark Twain's novel, Personal Recollections of Joan of Arc into a full length play involves in-depth research into French and English society, religion, war strategy, The Hundred Years War and many other aspects that affected the young Jehanne d'Arc. Research also included in-depth study of the life of Mark Twain. After months of research, the playwriting process began. The process ending with new knowledge in playwriting, dramatic structure and a work that reflects how Joan of Arc can inspire an individual as a true heroine. A staged reading of the play, Personal Recollections of Joan of Arc, was presented on Monday, December 3rd, 2012 at the Next Door in Johnson City, Tennessee.

Arc flash is one of the two primary hazards encountered by workers near electrical equipment. Most applications where arc flash may be encountered are alternating current (AC) electrical systems. However, direct current (DC) electrical systems are becoming increasingly prevalent with industries implementing more renewable energy sources and energy storage devices. Little research has been performed with respect to arc flash hazards posed by DC electrical systems, particularly energy storage devices. Furthermore, current standards for performing arc flash calculations do not provide sufficient guidance when working in DC applications. IEEE 1584-2002 does not provide recommendations for DC electrical systems. NFPA 70E provides recommendations based on conservative theoretical models, which may result in excessive personal protective equipment (PPE). Arc flash calculations seek to quantify incident energy, which quantifies the amount of thermal energy that a worker may be exposed to at some working distance. This thesis assesses arc flash hazards within a substation backup battery system. In addition, empirical data collected via a series of tests utilizing retired station batteries is presented. Lastly, a predictive model for determining incident energy is proposed, based on collected data.

A. Ádám conjectured that for any non-acyclic digraph D, there exists an arc whose reversal reduces the total number of cycles in D. In this thesis we characterize and identify structure common to all digraphs for which Ádám's conjecture holds. We investigate quasi-acyclic digraphs and verify that Ádám's conjecture holds for such digraphs. We develop the notions of arc-cycle transversals and reversal sets to classify and quantify this structure. It is known that Ádám's conjecture does not hold for certain infinite families of digraphs. We provide constructions for such counterexamples to Ádám's conjecture. Finally, we address a conjecture of Reid [Rei84] that Ádám's conjecture is true for tournaments that are 3-arc-connected but not 4-arc-connected.

Le contexte du marché automobile actuel est conditionné par deux facteurs principaux : la prise de conscience del'impact sur l'écologie de ce mode de transport et une concurrence mondiale exacerbée. Ainsi, de nombreusesétudes soulignent l'intérêt de concevoir des moteurs dont le ratio puissance sur masse soit maximisé (Down Sizing).Ainsi les carters-cylindres traditionnellement réalisés en fonte pour des raisons de comportement tribologique sontreconçus pour être fabriqués à partir d'alliages d'aluminium. Ces derniers apportent un gain de masse au groupemotopropulseur mais présentent de piètres propriétés tribologiques. Pour pallier ce défaut, des chemises en fontesont généralement insérées dans les blocs lors de leur coulée. Toutefois cette solution n'est pas optimale et lesprocédés de projection thermique sont de plus en plus mis en oeuvre pour remplacer ces chemises par une mincecouche protectrice qui sera en contact avec les segments.Dans ce contexte ce travail se focalise sur l'application du procédé de projection thermique arc-fil rotatif pour ledépôt de revêtements en acier sur la paroi interne des fûts de carters-cylindres. L'objectif principal est de contribuerà cerner les mécanismes physiques reliant les paramètres de projection et les propriétés des revêtements. Desinvestigations ont été menées sur les différentes étapes de la vie des particules : les mécanismes d'atomisation ontété observés et quantifiés, les comportements à l'étalement des particules et les modes de refroidissement deslamelles ont été déterminés au moyen d'analyses des phases cristallines et les effets des paramètres opératoiressur la structure des dépôts ont été évalués. L'ensemble apporte ainsi de nouveaux éléments pour la maîtrise del'application de la projection thermique à l'arc-fil en milieu confiné et des pistes sont proposées pour optimiser lespropriétés des dépôts. / The current automotive market's context is conditioned by two main factors : the rising awareness of theenvironmental impact of this transportation mode and a strong competition between automakers at the world level.Thus, many studies already underlined the relevance of the « down sizing » of the engine blocks.Thus, cylinders-blocks, traditionally made from cast iron given its excellent tribological behavior and low cost, arenow designed with hypoeutectic aluminium-silicon cast alloys. However, the weight reduction brought by thesealloys is counteracted by their poor tribological properties. Therefore, Thermal spray processes are more and moresolicited to address this issue with the application of thin protective coatings on the working surfaces of thecylinders-blocks.In this frame, the present work was focused on the application of steel coatings on the bores' inner walls of cylinderblocks using the rotative twin-wire arc spray process. The main objective was to contribute to the understanding ofphysical mechanisms linking the spray parameters and the coating properties. Every stages of particles' life werethus investigated : the atomization mechanisms were observed and quantified, particles' spreading and coolingbehaviours were determined by mean of crystallographic examinations and process parameters' effects on coatingstructure were estimated. Globally, this document provides new elements contributing to the understanding and thecontrol of the process and solutions are proposed to raise the coatings properties.

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The objective of this study was to utilize an electric arc furnace ¡]EAF¡^in a steel mill to melt municipal incinerator fly ash ¡]MIFA¡^of different sources ¡]Plants K1 and K2¡^ and evaluate its effectiveness in aspects of environment and economy. The results of full-scale tests have shown that slag thus generated by the EAF was found to be non-hazardous based on the TCLP result and also met the standard of CNS 14602. However, EAF dust thus obtained remained hazardous as it was originally a listed waste by Taiwan EPA. Test results have indicated that this novel treatment technology would not deteriorate the quality of steel billets and bars produced. Moreover, when melting MIFAs from Plant K1¡]with 2.00 wt¢H of MIFA¡^ and Plant K2 ¡]with 3.28 wt¢H of MIFA¡^, the air quality in the steel mill surroundings and off-gas from the stack were all below the regulatory limits. Thus, it would not cause additional pollution problems from this practice. Based on the total capacity of EAFs in Taiwan, it was estimated that these EAFs would be capable of melting fly ash generated by municipal incinerators in Taiwan. From the economic perspective, this melting practice would not lower the production rate of EAF steel-making and increase the tap-to-tap cycle time, consumption of electrical energy, consumption of oxygen, and consumption of graphite electrodes. Furthermore, through this novel practice, the contents of MIFA have turned out to be able to replace some portions of quick-lime and coke powder required for steel-making. Test results have also shown that 1 wt¢H of MIFA injection would generate additional 8.93 kg of slag and 2.76 kg of EAF dust. It was found that an additional cost of NT¢C318 per ton of MIFA treated would be resulted through this practice. This treatment cost is very low as compared with NT¢C8,000 per ton of waste treated by solidification and followed by landfilling. Assuming a melting cost of NT¢C5,000 per ton of MIFA is charged by EAFs, it would save more than ten million NT¢C per year for a municipal incinerator with an annual generation of 5,840 tons of MIFA. On the other hand, for a mini-mill with an annual capacity of 264,000 tons of billets, it would have an additional income of 37 million NT¢C if 3 wt¢H of MIFA is melted while making steel.

AgCdO is one of the most widely used contact materials in the world because of its outstanding performance. Nevertheless, due to environmental considerations, it will soon be completely forbidden by European environmental directives. Therefore, finding a good substitute is of crucial importance. Electrical arc erosion plays a crucial role in the reliability and life of power switching devices. Depending on the contact material's behavior in response to an electrical arc, surface damage can induce severe changes in contact material properties that will impact the power switching device's functioning. Consequently, electrical arc effects and consequences on the contact material surface are of first importance. In this context, we have focused our research activities on the following axes. First of all, in order to better understand AgCdO (Current contact material in aerospace industry) and AgSnO₂(Potential candidate to AgCdO substitution) arc erosion behaviors, arc erosion experiments, where the power switching devices have been subjected to different numbers of arc discharges, have been realized. Further, a general macroscopic electrical contact arc erosion model valid for low and high currents was developed. To compare model results to experimental data, this model describes the complete breaking process of electrical contacts and gives the total amount of material removed after one breaking operation. In parallel, arc erosion experiments on AgCdO power switching devices have been conducted at high currents (0 -> 1000 A) in order to validate the arc erosion model. Next, using the general arc erosion model, the properties having the greatest influence on the electrical arc erosion process have been determined through simulations on silver contact material. At this stage, ab initio calculations were needed to obtain ranges of variation of certain silver contact material properties. Finally, an investigation of the trends of changing local contact material on these identified material properties was performed. This study composition of AgSnO₂was based on ab initio calculations for two different oxide compositions of AgSnO₂. These will allow us to give directions to aid the design of a good substitute for AgCdO, and therefore, to complete the main objective of this research work.

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