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Modeled Estimates of Solar Direct Normal Irradiance and Diffuse Horizontal Irradiance in Different Terrestrial LocationsAbyad, Emad January 2017 (has links)
The transformation of solar energy into electricity is starting to impact to overall worldwide energy production mix. Photovoltaic-generated electricity can play a significant role in minimizing the use of non-renewable energy sources. Sunlight consists of three main components: global horizontal irradiance (GHI), direct normal irradiance (DNI) and diffuse horizontal irradiance (DHI). Typically, these components are measured using specialized instruments in order to study solar radiation at any location. However, these measurements are not always available, especially in the case of the DNI and DHI components of sunlight. Consequently, many models have been developed to estimate these components from available GHI data. These models have their own merits. For this thesis, solar radiation data collected at four locations have been analyzed. The data come from Al-Hanakiyah (Saudi Arabia), Boulder (U.S.), Ma’an (Jordan), and Ottawa (Canada). The BRL, Reindl*, DISC, and Perez models have been used to estimate DNI and DHI data from the experimentally measured GHI data. The findings show that the Reindl* and Perez model outcomes offered similar accuracy of computing DNI and DHI values when comparing with detailed experimental data for Al-Hanakiyah and Ma’an. For Boulder, the Perez and BRL models have similar estimation abilities of DHI values and the DISC and Perez models are better estimators of DNI. The Reindl* model performs better when modeling DHI and DNI for Ottawa data. The BRL and DISC models show similar metrics error analyses, except in the case of the Ma’an location where the BRL model shows high error metrics values in terms of MAE, RMSE, and standard deviation (σ). The Boulder and Ottawa locations datasets were not complete and affected the outcomes with regards to the model performance metrics. Moreover, the metrics show very high, unreasonable values in terms of RMSE and σ. It is advised that a global model be developed by collecting data from many locations as a way to help minimize the error between the actual and modeled values since the current models have their own limitations. Availability of multi-year data, parameters such as albedo and aerosols, and one minute to hourly time steps data could help minimize the error between measured and modeled data. In addition to having accurate data, analysis of spectral data is important to evaluate their impact on solar technologies.
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Modelování vývoje povrchu patra člověka od 7 let do dospělosti / Modelling of human palate surface development from 7 years to adulthoodMoravec, Tomáš January 2020 (has links)
The diploma thesis deals with the differences in the development of the palate in girls and boys within five age groups in the age range of 7 to 19 years, using methods of geometric morphometry. Furthermore, the work deals with the monitoring of sexual dimorphism in the development of the palate. Understanding palate growth, knowledge of differences in its development and changes related to sexual dimorphism are very useful, as the results of this study will serve as a comparative standard for palate defects in the Czech population, but also for appropriate planning of orthodontic procedures. The material consists of 228 gypsum castings of palate without any pathologies, 112 of which belonged to boys and 116 girls of the Czech population. Thus, transverse data are used in our study. The subjects were divided into five age groups 7, 10, 12, 15 and 19 with respect to gender. Age changes of the entire palate surface were modeled using geometric morphometry methods (Coherent point drift - Dense correspondence analysis, Per vertex T- test and Principal component analysis). To visualize the results, superprojection color maps, maps of significance and superprojection. The results show the greatest variability in the form of palate in girls of groups 10 and 12 years and in boys of groups 10 years, and...
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RANS & WMLES Simulations of Compressor Corner SeparationPoulain, Arthur January 2019 (has links)
In axial compressor, corner separation phenomenon can occur between the blade surface and the hub. This leads to high total pressure losses, blockage and may worsen to surge. Various studies on NACA65-009 blade were previously performed experimentally and numerically to predict the corner separation. The LMFA showed that RANS simulations tend to overestimate it while the Wall-Resolved LES (WRLES) was able to well capture it. The conclusions drawn on RANS are validated here with another solver software. An extensive parametric study is performed on RANS which highlights the good performance of two non-linear turbulence models k − ω Wilcox QCR and EARSM k − kl for for predicting the topology and the intensity of corner separation. They are however very dependent on the mesh and the numerics. A Wall-Modeled LES (WMLES) is then computed. It reproduces well the topology of the separation given by the experiments and predicts similar anisotropy to the WRLES. Nevertheless it shows high sensitivity to the level of turbulence close to the endwall and the boundary layer profile of the upstream flow. Finally, this confirms that the WMLES is a promising alternative to the WRLES in order to study the corner separation on more costly geometries (several blades for instance). / I axiell kompressor kan hörnseparationsfenomen uppstå mellan bladytan och navet. Konsekvenserna är stora totala tryckförluster och kompressor blockering. Olika studier på NACA65-009 bladet utfördes tidigare experimentellt och numeriskt för att förutsäga hörnseparationen. LMFA visade att RANS simuleringar tenderar att överskatta den hörnseparationen medan Vägg-Löst LES (WRLES på engelska) kunde fånga bra den. Slutsatserna som dras om RANS valideras här med en annan lösningsprogramvara. En omfattande parametrisk studie utförs på RANS som belyserde goda prestandan för två icke-linjära turbulensmodeller k − ω Wilcox QCRoch EARSM k − kl för att förutsäga topologin och intensiteten för hörnseparation. Dock är de mycket beroende av nät och numerik. En Vägg-Modell LES (WMLES på engelska) beräknas sedan. Det reproducerar väl topologin för separationen som ges av experimenten och förutsäger liknande anisotropi som WRLES. Dock visar det hög känslighet för turbulensnivån nära ändväggen och gränsskiktsprofilen för uppströmsflödet. Slutligen bekräftar detta att WMLES är ett lovande alternativ till WRLES för att studera hörnseparationen på dyrare geometrier (till exempelflera blad).
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Capitalisation et partage de connaissances d’analyse de traces numériques d’activités : assister le suivi de l'activité dans les environnements de formation à base de simulateur pleine échelle / Capitalizing and sharing analysis knowledge of digital traces of activities : assist the monitoring of activity in full scale simulator-based training environmentsChampalle, Olivier 04 July 2014 (has links)
Nos recherches s'inscrivent dans le domaine de l'ingénierie des connaissances et plus particulièrement dans la capitalisation et le partage de connaissances d'observation et d'analyse de traces numériques d'activités. Dans ce cadre, nous basons notre approche sur le concept de la trace modélisée (M-Trace) développée par l'équipe SILEX. Au travers de notre approche nous donnons la possibilité d'exploiter des traces numériques d'activités de bas niveaux pour faire émerger des connaissances de plus haut niveaux obtenues via des transformations à base de règles. Ces règles modélisent des connaissances d'observation et d'analyse de différents utilisateurs et sont capitalisables et partageables entre ces derniers. Nous complétons notre proposition en fournissant une visualisation synthétique des niveaux de connaissances et de leurs observés. Via un modèle générique de trace, que nous avons développé, cette synthèse visuelle est navigable afin de permettre aux utilisateurs d'explorer les différents niveaux de connaissances et de reconstituer le chemin de construction des observables entre les niveaux, facilitant ainsi l'analyse. Nos différentes propositions ont été réifiées dans un logiciel du nom de D3KODE (« Define, Discover, and Disseminate Knowledge from Observation to Develop Expertise »). Ce logiciel a été mis à l'épreuve dans le contexte de la formation professionnelle sur les simulateurs pleine échelle du groupe EDF utilisés pour la formation et le perfectionnement des agents de conduite de centrale nucléaire. Dans un tel cadre l'observation, l'analyse et le débriefing des interactions individuelles et collectives des opérateurs sont des activités critiques et particulièrement dense notamment pour les jeunes formateurs. Les données collectées sont difficilement exploitables dû à leur grande quantité et à leur très bas niveau nécessitant une expertise forte que tous les formateurs ne possèdent pas. Ce travail a donné lieu à une évaluation en contexte réel sur simulateur pleine échelle et à des résultats significatifs permettant de valider notre approche et d'encourager des perspectives de recherche nombreuses / Our research takes place in the field of knowledge engineering. In particularly we focus our study in capitalizing and sharing knowledge of observation and analysis of digital traces. In this context, we base our approach on the concept of modeled trace (M-Trace) developed by the SILEX team. Our approach give the possibility to exploit low levels digital traces in order to extract higher knowledge level through rule-based transformations. These rules modelize the knowldege of observation and analysis of different users. Rules can be capitalized and shared between users. We complete our proposal by providing a synthetic visualization of the knowledge levels with observed elements from the activity. By means of a generic trace model, that we have specified, users can explore the different abstraction level in purposes of investigation in order to better understand and analyze the activity. Our proposals have been implemented in a prototype, called D3KODE (« Define, Discover, and Disseminate Knowledge from Observation to Develop Expertise »), allowing the processing, representation and visualization of traces. D3KODE was applied in the context of professional training on the nuclear power plant full-scope simulator of the EDF group designed to maintain and enhance the knowledge and skills of Nuclear Power Plant control room staff. In such context, the observation, analysis and debriefing of individual and collective interactions of trainees’ operators is a dense activity that require attention and constant alertness of the trainers throughout the simulation, especially for the young trainers who do not have the expertise of confirmed trainers. The amount of data collected during a simulation is big and very low levels. They are difficult to analyse manually in order to extract high level information reflecting the behaviour of trainees. In such a context, understand and follow the activity requires a strong expertise that all trainers don’t have. So as to validate our approach, D3KODE was evaluated in a real context according to a comparative protocol conducted with a team of trainers from EDF Group. The evaluation gave significant results to validate our approach and encourage many research opportunities
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New enriched element methods for unsteady reaction-advection-diffusion models / Novos métodos de elementos finitos enriquecidos aplicados a modelos de reação-advecção-difusão transientesJairo Valões de Alencar Ramalho 20 December 2005 (has links)
Several problems in physics and engineering are modeled by reaction-advection-diffusion (RAD) equations. However, when the diffusive terms are small compared with the other ones, these problems can become difficult to solve numerically. Besides, formulating the unsteady version of these models in a semi-discrete fashion, it can be interpreted that the overall diffusivity gets smaller as the time step decreases. To overcome these drawbacks, this thesis considers the development of Galerkin (or Petrov-Galerkin) finite element methods based on approximation spaces enriched by residual-free bubbles (RFB) or multiscale functions. Beginning with the unsteady reaction-diffusion problem, new methods using multiscale functions are presented which improve the solutions in the reaction-dominated regime and/or when small time steps are adopted. They also give rise to a general concept of stabilizing unsteady problems differently along the time. In the following, it is shown that switching RFB by suitable multiscale functions in the elements connected to the outflow boundaries of the domain increases the accuracy of the solutions in this region for RAD problems with advection. Next, this methodology is further studied for systems of RAD equations. In a final contribution, an extension of the RFB method is introduced for the shallow waters equations. All these methods are tested through benchmark problems and compared with stabilized methods presenting stable and accurate results. / A modelagem de vários problemas físicos e de engenharia envolve a solução de problemas de transporte do tipo reação-advecção-difusão (RAD), porém, estes podem tornar-se singularmente perturbados quando os termos difusivos são pequenos comparados aos demais. Além disso, ao adotar formulações semi-discretas em problemas transientes, observa-se que diminuir o passo de tempo tem um efeito de redução da componente difusiva. Para superar estas dificuldades, esta tese considera o desenvolvimento de métodos de elementos finitos de Galerkin (ou Petrov-Galerkin) baseados em espaços de aproximação enriquecidos por funções bolhas livres do resíduo (RFB) ou funções multiescala. Começando pelo problema de reação-difusão transiente, novos métodos utilizando funções multiescala são apresentados, os quais melhoram as soluções no regime reativo-dominante e/ou quando pequenos passos de tempo são adotados. Com estes métodos, discute-se também o conceito de estabilização variável ao longo do tempo para problemas transientes. Na seqüência, verifica-se que utilizar funções multiescala nos elementos conectados às fronteiras de saída de fluxo do domínio e RFB nos demais elementos aumenta a precisão das soluções nesta região em problemas de RAD com advecção dominante. A seguir, esta metodologia é estudada para sistemas de RAD. Como contribuição final, estende-se o método RFB para o modelo de águas rasas. Todos estes métodos são submetidos a testes de robustez e comparados com métodos estabilizados, apresentando resultados estáveis e precisos.
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Novos métodos de elementos finitos enriquecidos aplicados a modelos de reação-advecção-difusão transientes / New enriched element methods for unsteady reaction-advection-diffusion modelsRamalho, Jairo Valões de Alencar 20 December 2005 (has links)
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Previous issue date: 2005-12-20 / Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior / Several problems in physics and engineering are modeled by reaction-advection-diffusion (RAD) equations. However, when the diffusive terms are small compared with the other ones, these problems can become difficult to solve numerically. Besides, formulating the unsteady version of these models in a semi-discrete fashion, it can be interpreted that the overall diffusivity gets smaller as the time step decreases. To overcome these drawbacks, this thesis considers the development of Galerkin (or Petrov-Galerkin) finite element methods based on approximation spaces enriched by residual-free bubbles (RFB) or multiscale functions. Beginning with the unsteady reaction-diffusion problem, new methods using multiscale functions are presented which improve the solutions in the reaction-dominated regime and/or when small time steps are adopted. They also give rise to a general concept of stabilizing unsteady problems differently along the time. In the following, it is shown that switching RFB by suitable multiscale functions in the elements connected to the outflow boundaries of the domain increases the accuracy of the solutions in this region for RAD problems with advection. Next, this methodology is further studied for systems of RAD equations. In a final contribution, an extension of the RFB method is introduced for the shallow waters equations. All these methods are tested through benchmark problems and compared with stabilized methods presenting stable and accurate results. / A modelagem de vários problemas físicos e de engenharia envolve a solução de problemas de transporte do tipo reação-advecção-difusão (RAD), porém, estes podem tornar-se singularmente perturbados quando os termos difusivos são pequenos comparados aos demais. Além disso, ao adotar formulações semi-discretas em problemas transientes, observa-se que diminuir o passo de tempo tem um efeito de redução da componente difusiva. Para superar estas dificuldades, esta tese considera o desenvolvimento de métodos de elementos finitos de Galerkin (ou Petrov-Galerkin) baseados em espaços de aproximação enriquecidos por funções bolhas livres do resíduo (RFB) ou funções multiescala. Começando pelo problema de reação-difusão transiente, novos métodos utilizando funções multiescala são apresentados, os quais melhoram as soluções no regime reativo-dominante e/ou quando pequenos passos de tempo são adotados. Com estes métodos, discute-se também o conceito de estabilização variável ao longo do tempo para problemas transientes. Na seqüência, verifica-se que utilizar funções multiescala nos elementos conectados às fronteiras de saída de fluxo do domínio e RFB nos demais elementos aumenta a precisão das soluções nesta região em problemas de RAD com advecção dominante. A seguir, esta metodologia é estudada para sistemas de RAD. Como contribuição final, estende-se o método RFB para o modelo de águas rasas. Todos estes métodos são submetidos a testes de robustez e comparados com métodos estabilizados, apresentando resultados estáveis e precisos.
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L'Homme et la mort au néolithique précéramique B : l'exemple de Tell Aswad / Man and Death in pre-pottery neolithic B : Exemple Tell AswadKhawam, Rima 15 December 2014 (has links)
Tell Aswad, situé à environ 30km à l’Est / Sud-Est de Damas, est un grand tell d’environ 6 hectares dont la hauteur maximale ne dépasse pas de 4,50 m la grande plaine lacustre qui l’entoure. Le site de Tell Aswad datant entièrement du Néolithique Précéramique B (entre 8200 et 7500 av. J.-C.) est un site de référence du Levant Central. Ces populations, complètement agriculteurs/éleveurs, montrent des liens entre les populations et les cultures du Levant Nord et Sud. Les niveaux attribués à l’horizon PPNB ancien, période mal connue au Levant Sud, lui donne une grande importance historique au niveau régional. Ainsi, ce site offre une documentation rare qui peut être utilisées dans la recherche des origines du PPNB dans la région et les identités culturelles qui lui correspondent. Il nous a offert une riche documentation sur les pratiques funéraires. Répartis sur presque la totalité de son occupation, plus de 119 individus ont été exhumés. Les résultats nous indiquent la présence d’une continuité diachronique des pratiques funéraires tout au long de l’occupation, celles-ci étant originaire d’une tradition ancestrale. Elles révèlent le recours aux funérailles uniques mais se spécifient par des funérailles multiples, à travers le prélèvement des crânes. Chacun de ces deux modèles résulterait d’un choix imposé et sélectif issu du système social (hiérarchisé), indiquant la manière dont le défunt doit être inhumé. Les différents traitements des crânes prélevés, dont le surmodelage, correspondraient à des « rituelles» et pratiques funéraires hautement culturalisées. Elles témoignent de l’ordre social et de l’intégrité du groupe et matérialisent l’un des traits majeurs de l’identité culturels des sociétés Néolithiques du PPNB à Tell Aswad. L’étude de l’organisation spatiale des sépultures au cours de l’occupation PPNB de Tell Aswad, révèle un changement des lieux d’inhumations, depuis l’inhumation dans des maisons, à l’intérieur de la cellule familiale, jusqu’à la conception de lieux spécifiques dédiés aux pratiques funéraires. L’organisation spatiale de ces lieux devient pour nous une source supplémentaire témoignant de l’organisation sociale dans ce site. / Tell Aswad, located 30 km East/South-East of Damascus, is a nearly 6 hectares tell not exceeding 4,5 meters height above the great lacustrian plain surrounding. The whole stratigraphy of the site dates from PPNB (8200-7500 B.C.), it's a reference site for the Central Levant because of the farmer/cattle breeder population showing connections between Southern and Northern Levant. The ancient PPNB levels, poorly understood in South Levant, give to the site an important historical status on a regional level. Thus, Tell Aswad offers us a rare documentation used for a better understanding of the PPNB period origins in the area and the cultural identities corresponding. The data are especially rich for the funeral practices. More than 119 individuals have been excavated spread on the entire occupation. Our results indicate the presence of a diachronic continuity of the funeral practices throughout the occupation due to an ancestral tradition. They reveal the use of simple burials but also specificity in the multiple burials by means of the skull withdrawal. Both models result from a selective choice imposed by the social system (hierarchical), indicating how the deceased had to be buried. The variability inside the skull treatment including the modeled skulls correspond to "ritual" and funerary practices highly culturalized. They reflect a social order and a group integrity materializing one of the major feature of the cultural identity of Neolithic PPNB society in Tell Aswad. Studying the spatial organization of the burials during the PPNB occupation of Tell Aswad reveals changes in burial sites, from burials in the house inside the family unit until the creation of specific area dedicated to funerary practices. The spatial organization of these areas becomes for our research a supplementary testimony of the social organization in the site.
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Zeitschrift für Recht und Islam (ZR&I)23 May 2017 (has links) (PDF)
Eine wissenschaftliche Gesellschaft kann ihren inneren Austausch und ihre Wirkung nach Außen nur sicherstellen, wenn sie ihren Mitgliedern und auswärtigen Interessierten ein zeitgemäßes Diskussionsforum bietet. Angesichts des gestiegenen Bedarfs an zuverlässigen Informationen über das islamische Recht und die rechtlichen Entwicklungen in islamisch geprägten Staaten besteht seitens der GAIR die Notwendigkeit, hierzu einen verantwortungsvollen Beitrag zu leisten. Um dieser Aufgabe gerecht zu werden, wird zukünftig der Schwerpunkt der GAIR-Mitteilungen deutlich stärker auf den fachlichen Diskurs gelegt. Das neue Format deckt neueste Entwicklungen in Gesetzgebung und Rechtsprechung aller Rechtsgebiete im In- und Ausland ab, soweit sie das Recht islamisch geprägter Staaten oder aber Menschen aus solchen Staaten betreffen. Wesentlich ergänzt wird dieses Angebot durch Tagungsberichte, Rezensionen und Aufsätze, in denen auch islamrechtliche Fragestellungen diskutiert werden.
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Zeitschrift für Recht und Islam (ZR&I)23 May 2017 (has links)
Die Zeitschrift für Recht und Islam (ZRI) (vormals GAIR-Mitteilungen) ist die Vereinszeitschrift der Gesellschaft für Arabisches und Islamisches Recht e.V. Neben Nachrichten aus dem Verein befasst sich die ZRI vor allem mit neuen Entwicklungen zum und im Recht islamisch geprägter Staaten, gibt einen Überblick über die Gesetzgebung im In– und Ausland, berichtet über aktuelle Rechtsprechung und Fatawa, sichtet jüngst erschienene Literatur und enthält Rezensionen, Tagungsberichte und Aufsätze.
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GAIR-Mitteilungen27 October 2014 (has links)
Eine wissenschaftliche Gesellschaft kann ihren inneren Austausch und ihre Wirkung nach Außen nur sicherstellen, wenn sie ihren Mitgliedern und auswärtigen Interessierten ein zeitgemäßes Diskussionsforum bietet. Angesichts des gestiegenen Bedarfs an zuverlässigen Informationen über das islamische Recht und die rechtlichen Entwicklungen in islamisch geprägten Staaten besteht seitens der GAIR die Notwendigkeit, hierzu einen verantwortungsvollen Beitrag zu leisten. Um dieser Aufgabe gerecht zu werden, wird zukünftig der Schwerpunkt der GAIR-Mitteilungen deutlich stärker auf den fachlichen Diskurs gelegt. Das neue Format deckt neueste Entwicklungen in Gesetzgebung und Rechtsprechung aller Rechtsgebiete im In- und Ausland ab, soweit sie das Recht islamisch geprägter Staaten oder aber Menschen aus solchen Staaten betreffen. Wesentlich ergänzt wird dieses Angebot durch Tagungsberichte, Rezensionen und Aufsätze, in denen auch islamrechtliche Fragestellungen diskutiert werden.
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