Spelling suggestions: "subject:"extremely""
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Delayed response of the global total electron content to solar EUV variationsJacobi, Christoph, Jakowski, Norbert, Schmidtke, Gerhard, Woods, Thomas N. 24 October 2016 (has links) (PDF)
The ionospheric response to solar extreme ultraviolet (EUV) variability during 2011–2014 is shown by simple proxies based on Solar Dynamics Observatory/Extreme Ultraviolet Variability Experiment solar EUV spectra. The daily proxies are compared with global mean total electron content (TEC) computed from global TEC maps derived from Global Navigation Satellite System dual frequency measurements. They describe about 74% of the intra-seasonal TEC variability. At time scales of the solar rotation up to about 40 days there is a time lag between EUV and TEC variability of about one day, with a tendency to increase for longer time scales.
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Efficiently feeding single-mode fiber photonic spectrographs with an extreme adaptive optics system: on-sky characterization and preliminary spectroscopyJovanovic, N., Cvetojevic, N., Schwab, C., Norris, B., Lozi, J., Gross, S., Betters, C., Singh, G., Guyon, O., Martinache, F., Doughty, D., Tuthill, P. 03 August 2016 (has links)
High-order wavefront correction is not only beneficial for high-contrast imaging, but also spectroscopy. The size of a spectrograph can be decoupled from the size of the telescope aperture by moving to the diffraction limit which has strong implications for ELT based instrument design. Here we present the construction and characterization of an extremely efficient single-mode fiber feed behind an extreme adaptive optics system (SCExAO). We show that this feed can indeed be utilized to great success by photonic-based spectrographs. We present metrics to quantify the system performance and some preliminary spectra delivered by the compact spectrograph.
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L'approche hydrogéomorphologique : pratiques, valorisations et développement d'une méthode de cartographie des zones inondables / Hydrogeomorphological approach : practices, valuations and development of a floodplain mapping methodMontané, Antonin 04 July 2014 (has links)
La connaissance de l’aléa inondation est un enjeu croissant pour la gestion du risque inondation. En France, afin de répondre à la demande des pouvoirs publics de cartographier les zones inondables, la cartographie hydrogéomorphologique émerge. Cette approche naturaliste, développée durant les années 1980, se propagea dans une large partie du Sud de la France. Aujourd’hui, la cartographie hydrogéomorphologique est une méthode reconnue pour sa fiabilité, mais elle stagne en termes d’applications et de développement dans de nouveaux territoires. Afin d’améliorer la connaissance de la prise en compte de la cartographie hydrogéomorphologique dans un cadre règlementaire, une analyse de 282 PPRI a été menée. Cette analyse a permis de dégager les modalités de prise en compte de la cartographie hydrogéomorphologique, mais également d’émettre des hypothèses sur les raisons de leur développement. La réalisation de MNZI (Modèle Numériques de Zones Inondables) sur des cours d’eau français et canadiens, a permis de mettre en avant l’adaptabilité de la cartographie hydrogéomorphologique à des contextes physiques différents, mais aussi d’apporter une réponse à la demande de prise en compte de cartographie de crue extrême de la Directive Inondation. L’évolution cartographique proposée dans ce travail comprend une réflexion autour de la légende des AZI, mais aussi sur le concept de cartographie positive. A travers les aspects cartographiques, règlementaires et géomorphologiques abordés, nous finissons par proposer un modèle de développement de la cartographie hydrogéomorphologique. / Flood hazard knowledge is increasingly becoming critical in flood risk management. The hydrogeomorphological mapping emerged in France, aiming to provide authorities with floodplain cartography. That naturalistic approach, developed in the 1980 decade, spread through the South of France. Today, the hydrogeomorphological mapping is widely recognized for its reliability. Though, it stagnates in terms of applications and development in new territories. The analysis of 282 PPRI (Flood Risk Prevention Plans) was performed in order to assess the extent of usage of hydrogeomorphological mapping in flood risk regulatory framework. That analysis highlighted how hydrogeomorphological mapping is used in the French flood risk management. NMFP (Numerical Model of Floodplain) production on French and Canadian rivers showed how the hydrogeomorphological interpretation could be adaptable to different physical contexts. It also answers to the European “Floods Directive” that asks for an extreme flood mapping. The cartographic evolution proposed in this research particularly includes AZI (Floodplains maps) legend simplification. It also makes proposals on a flood risk “positive mapping” of. Through cartographic, regulatory and geomorphologic aspects, this research finally proposes a development model applicable to hydrogeomorphological mapping.
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A robust and reliable data-driven prognostics approach based on Extreme Learning Machine and Fuzzy Clustering / Une approche robuste et fiable de pronostic guidé par les données robustes et basée sur l'apprentissage automatique extrême et la classification floueJaved, kamran 09 April 2014 (has links)
Le pronostic industriel vise à étendre le cycle de vie d’un dispositif physique, tout en réduisant les couts d’exploitation et de maintenance. Pour cette raison, le pronostic est considéré comme un processus clé avec des capacités de prédiction. En effet, des estimations précises de la durée de vie avant défaillance d’un équipement, Remaining Useful Life (RUL), permettent de mieux définir un plan d’action visant à accroitre la sécurité, réduire les temps d’arrêt, assurer l’achèvement de la mission et l’efficacité de la production.Des études récentes montrent que les approches guidées par les données sont de plus en plus appliquées pour le pronostic de défaillance. Elles peuvent être considérées comme des modèles de type boite noire pour l’ étude du comportement du système directement `a partir des données de surveillance d’ état, pour définir l’ état actuel du système et prédire la progression future de défauts. Cependant, l’approximation du comportement des machines critiques est une tâche difficile qui peut entraîner des mauvais pronostic. Pour la compréhension de la modélisation du pronostic guidé par les données, on considère les points suivants. 1) Comment traiter les données brutes de surveillance pour obtenir des caractéristiques appropriées reflétant l’ évolution de la dégradation? 2) Comment distinguer les états de dégradation et définir des critères de défaillance (qui peuvent varier d’un cas `a un autre)? 3) Comment être sûr que les modèles définis seront assez robustes pour montrer une performance stable avec des entrées incertaines s’ écartant des expériences acquises, et seront suffisamment fiables pour intégrer des données inconnues (c’est `a dire les conditions de fonctionnement, les variations de l’ingénierie, etc.)? 4) Comment réaliser facilement une intégration sous des contraintes et des exigence industrielles? Ces questions sont des problèmes abordés dans cette thèse. Elles ont conduit à développer une nouvelle approche allant au-delà des limites des méthodes classiques de pronostic guidé par les données. / Prognostics and Health Management (PHM) aims at extending the life cycle of engineerin gassets, while reducing exploitation and maintenance costs. For this reason,prognostics is considered as a key process with future capabilities. Indeed, accurateestimates of the Remaining Useful Life (RUL) of an equipment enable defining furtherplan of actions to increase safety, minimize downtime, ensure mission completion andefficient production.Recent advances show that data-driven approaches (mainly based on machine learningmethods) are increasingly applied for fault prognostics. They can be seen as black-boxmodels that learn system behavior directly from Condition Monitoring (CM) data, usethat knowledge to infer its current state and predict future progression of failure. However,approximating the behavior of critical machinery is a challenging task that canresult in poor prognostics. As for understanding, some issues of data-driven prognosticsmodeling are highlighted as follows. 1) How to effectively process raw monitoringdata to obtain suitable features that clearly reflect evolution of degradation? 2) Howto discriminate degradation states and define failure criteria (that can vary from caseto case)? 3) How to be sure that learned-models will be robust enough to show steadyperformance over uncertain inputs that deviate from learned experiences, and to bereliable enough to encounter unknown data (i.e., operating conditions, engineering variations,etc.)? 4) How to achieve ease of application under industrial constraints andrequirements? Such issues constitute the problems addressed in this thesis and have ledto develop a novel approach beyond conventional methods of data-driven prognostics.
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Discrete Parameter Estimation for Rare Events: From Binomial to Extreme Value DistributionsSchneider, Laura Fee 26 April 2019 (has links)
No description available.
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La mise en récit de l’accident de Fukushima Dai Ichi par le directeur de la centrale : Le coping en situation extrême / The narrative of the Fukushima Dai Ichi accident by the plant's supervisor : coping in extreme situationsAfrouss, Aissame 19 December 2017 (has links)
Plusieurs analyses ont tenté d’analyser l’accident de Fukushima Dai Ichi. Ces publications proposent surtout des mesures préventives et mobilisent des approches classiques de la sécurité nucléaire. Ainsi, l’aspect humain de la gestion de la crise en temps réel trouve peu de place.Les auditions par le Gouvernement de Yoshida, le directeur de la centrale, permettent de combler ce vide. Nous les considérons comme un récit de vie, dans lequel le directeur dépeint son vécu en situation extrême. Durant quatre jours, le collectif autour de lui fait face à des conditions d’intervention extrêmement entravées et avec des ressources très limitées. Malgré une menace de leur intégrité physique, psychologique et sociale, ils parviennent à surmonter la difficulté et à éviter le pire.Le concept de "coping" désigne justement les efforts effectués dans des situations stressantes. Ces efforts dépendent de la représentation que l’individu a de la situation. Dès lors, une approche qualitative du récit de Yoshida nous permet d’étudier les stratégies de coping mobilisées pendant l’accident et les différents facteurs qui les ont influencés. Nos résultats montrent que si ces stratégies sont actives au début de la crise, l’impossibilité d’agir et le tarissement des ressources rendent Yoshida passif et le plongent dans des considérations morbides. L’anticipation et l’élaboration de solutions alternatives laissent leur place à la résignation.D’autre part, hormis les explications techniques et opérationnelles, le directeur nous décrit dans son récit les conditions émotionnelles, cognitives et relationnelles de la gestion de l’accident. Il rend hommage à ses travailleurs qui sont décrits comme des héros méconnus. La construction du récit de vie lui permet de réhabiliter son collectif en se représentant comme membre d’un groupe ayant sauvé le Japon en prenant des risques inouïs, sans être soutenu.Les récits de vie nous donnent un accès aux événements tels qu’ils ont été vécus. Ils nous éclairent sur les ressorts qui permettent aux organisations de redéfinir leur action dans des situations à la fois dangereuses et urgentes. Ils remettent ainsi l’humain au centre des analyses des accidents. / The Fukushima Dai Ichi nuclear accident was analysed in many publications. These studies followed classical approaches and focused on drawing lessons to improve nuclear facilities’ preventive measures. Therefore, the human aspect of the crisis management is not addressed enough.The hearings of the plant’s superintendent Yoshida by the Government’s inquiry Committee may help us tackle this issue. We consider that the transcriptions of the hearings are a life narrative of superintendent Yoshida. This narrative depicts his experience throughout an extreme situation. During four days, the workers around him dealt with extremely harsh conditions and had very limited resources available. Despite the threat to their physical, psychological and social integrity, they managed to overcome the hardship and prevented the worse from happening.Coping is a notion that refers to the specific efforts carried out to adjust to stressful situations. These efforts depend on the representation the individual forms of the situation. A qualitative study of Yoshida’s narrative allows us then to understand coping strategies carried out and the individual and contextual factors that came into play. We found that coping strategies were active after the arrival of the tsunami, but with the scarcity of resources and the impossibility to intervene on the reactors, Yoshida became more passive and began having morbid thoughts. As the crisis unfolded, anticipation and elaboration of alternative solutions left room to resignation.The narrative provides us technical and operational explanations, but Yoshida also describes emotional, cognitive and relational aspects of the crisis management. He pays tribute to the workers depicted as unsung heroes. The construction of his life narrative allows him to rehabilitate his collective of workers that took incredible risks to save Japan with very little support.Life narratives provide us with events as they have been experienced. They highlight the mechanisms that help organisations redefine their action in dangerous and urgent situations. Life narratives help us put the human back at the centre of accidents analyses.
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The ethics of reporting on radical nationalist groups in SwedenAxelsson, Sofie January 2019 (has links)
Radical nationalist groups are growing in Sweden as well as in the rest of the world due to contemporary political, cultural and social rationale, where the internet is used as a catalyzer and tool to organize and spread their ideologies. Simultaneously, the structures and the system that hold journalism seem to be altering at a similar speed. The journalistic reporting on radical nationalist groups has, for this reason, become increasingly difficult. The alt-right, a radical nationalist group in the US expanded much because of the oxygen that American journalists added in an attempt to raise awareness of the danger or the highly problematic opinions that these groups sometimes stand for (Faris et.al 2018). A similar trend in Sweden is not yet visible but the lack of an ethical code of conduct when reporting on radical nationalist groups speaks for unpreparedness. This study aims to understand the ethical approach of Swedish journalists when reporting on radical nationalist groups through the interviews of 8 journalists. ¨´The theoretical approach is based on the structures that affect ethical decision-making along the hierarchy of influence model, by Shoemaker and Reese (1996) as well as journalists’ positioning of ideology and relativism, an ethical concept developed by Plaisance (2005). Based on the interview data collected for this study, some of the journalists in Sweden claim to be consequence neutral, thus it can be assumed that the responsibility of providing accumulated attention to radical nationalist groups which contribute to their expansion is not taken by many journalists. The focus of the interviewed Swedish journalists is rather on up front nazis than the dubious groups spreading online, with some exceptions, which could help explain the more carefree approach. However, the challenges of similar groups’ potential spreading in the near future is an important reason to address ethical approaches on how to best report on radical nationalist groups promptly.
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Atividade lipolítica e biodiversidade de fungos filamentosos derivados da Antártica. / Lipase activity and biodiversity of filamentous fungi derived from Antarctica.Nobre, Fernando Suzigan 26 March 2013 (has links)
Lipases ativas em temperaturas frias estão amplamente distribuídas em micro-organismos que sobrevivem em temperaturas baixas, neste contexto, o isolamento de fungos de ambiente antártico pode ser considerado estratégico para obtenção de lipases a baixas temperaturas. O presente trabalho teve como objetivo avaliar a produção de lipases e a diversidade de fungos filamentosos isolados de amostras do ambiente Antártico. Um total de 253 isolados foi recuperado a partir de 10 amostras marinhas e quatro terrestres, dos quais 68 apresentaram resultados positivo e foram submetidos aos experimentos de avaliação da produção de lipase e caracterização da biodiversidade. Os fungos lipolíticos foram identificados como pertencentes aos gêneros: Geomyces, Penicillium, Cosmospora, Thelebolus, Chaetomium, Hypocrea, Antarctomyces, Mortierella e Cadophora. Em adição, alguns isolados de um mesmo ribotipo foram afiliados à ordem Mucorales e, outro, revelou ser uma potencial nova espécie pertencente ao filo Basidiomycota. O fungo Geomyces pannorum. AL1-1B foi selecionado como o melhor produtor de lipase e apresentou atividade de 761,68 U/L no 5° dia de cultivo em pH 8,0 a 15 °C, evidenciando o potencial biotecnológico na produção de lipase a baixas temperaturas. / Cold-active lipases are widely distributed in micro-organisms which survive in low temperatures, in this context; fungal isolation from Antarctic environment can be considered strategic for obtaining lipases at low temperatures. The present work aimed to assess the production of lipases and diversity of filamentous fungi isolated from samples of the Antarctic environment. A total of 253 isolates were retrieved from 10 marine and four terrestrial samples collected on the Antarctic continent, amongst then 68 presented positive results and were subjected to the experiments of lipase production evaluation and biodiversity characterization. Lipolytic fungi were identified as representatives of the genera: Geomyces, Penicillium, Cosmospora, Thelebolus, Chaetomium, Hypocrea, Antarctomyces, Mortierella and Cadophora. In addition, some isolates of the same ribotype were affiliated to the order Mucorales, and another one, showed to be a putative new species from phylum Basidiomycota. The fungus Geomyces pannorum AL1-1B was selected as the lipase best producer and showed activity of 761.68 U/L in the 5th day of cultivation at pH 8.0 at 15 °C, highlighting the biotechnological potential for lipase production at low temperatures.
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eXtreme Programming vs. etablerade systemutvecklingsmetoder : en jämförelseJohansson, Carolin January 2004 (has links)
Allt sedan 1960-talet har det utvecklats så många systemutvecklingsmetoder att det kan vara svårt, som systemutvecklare, att välja rätt metod till det utvecklingsprojekt som ska genomföras. För att underlätta valet av systemutvecklingsmetod kan ett jämförelseramverk vara användbart. Detta för att lättare kunna sätta sig in i de utvecklingsmetoder som finns till hands att välja mellan. Denna rapport fokuserar på att jämföra systemutvecklingsmetoden eXtreme Programming med Structured Systems Analysis and Design Method (SSADM) och Rational Unified Process (RUP). Detta görs med hjälp av ett jämförelseramverk. Syftet är att erhålla en djupare kunskap om vad eXtreme Programming är för en typ av systemutvecklingsmetod och vad den har att erbjuda som de mer etablerade metoderna, SSADM och RUP, inte kan erbjuda och vise versa. Resultatet av rapporten är ett jämförelseramverk som kan användas på ett strukturerat sätt för att erhålla information om systemutvecklingsmetoder. Vidare erhåller läsaren en djupare kunskap om en relativt ny systemutvecklingsmetod eXtreme Programming.
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Who gets the anti-establishment vote? Crisis, elections, and populism in Western Europe / Para quem vai o voto anti-establishment? Crise, eleições e populismo na Europa OcidentalFalabella, Leonardo Jamel Edim 18 August 2017 (has links)
Why does the extreme right grow in some parts of Europe while the radical left rises in others? In studies about both party groups, the hypothesis that economic distress provides them with opportunity is frequently tested. Yet, little effort has been employed in comparing their performances under different economic conditions. This article fills this gap through panel data analysis, with disaggregated data from eight countries in election years between 2002 and 2011. It finds that voting for extreme right parties increases significantly after the financial crisis outbreak of 2008, with no corresponding evidence for radical left parties. Also, extreme right support has a positive link to regional GDP per capita and a negative link to unemployment rates. In contrast, radical left parties perform better where unemployment is higher. The results suggest that economic downturns are mostly beneficial to extreme right parties, but this effect is increasingly neutralized in regions of high unemployment. / Por que a extrema direita cresce em alguns países europeus, ao passo que a esquerda radical cresce em outros? Em estudos sobre ambas as categorias de partido, testa-se frequentemente a hipótese segundo a qual eles têm janelas de oportunidade em crises. Ainda assim, pouco esforço vem sendo feito para comparar como eles se saem sob diferentes contextos econômicos. Este artigo preenche tal lacuna através de análise de dados em painel, com dados desagregados de oito países, em eleições entre 2002 e 2011. O artigo aponta que a votação da extrema direita aumenta significativamente com o desenrolar da crise de 2008, ao passo que não se encontram evidências correspondentes para a esquerda radical. Ademais, o apoio eleitoral à extrema direita é positivamente ligado a índices regionais de PIB per capita, e negativamente ligado a taxas de desemprego. Por contraste, partidos de esquerda radical se saem melhores onde o desemprego é alto. Os resultados sugerem que quedas na atividade econômica são majoritariamente benéficas à extrema direta, mas que tal efeito é crescentemente neutralizado em regiões de alto desemprego.
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