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41	Optimisation multi-niveau d’une application de traitement d’images sur machines parallèles / Multi-level optimisation of an image processing application on parallel machines Saidani, Tarik 06 November 2012 (has links) Cette thèse vise à définir une méthodologie de mise en œuvre d’applications performantes sur les processeurs embarqués du futur. Ces architectures nécessitent notamment d’exploiter au mieux les différents niveaux de parallélisme (grain fin, gros grain) et de gérer les communications et les accès à la mémoire. Pour étudier cette méthodologie, nous avons utilisé un processeur cible représentatif de ces architectures émergentes, le processeur CELL. Le détecteurde points d’intérêt de Harris est un exemple de traitement régulier nécessitant des unités de calcul intensif. En étudiant plusieurs schémas de mise en oeuvre sur le processeur CELL, nous avons ainsi pu mettre en évidence des méthodes d’optimisation des calculs en adaptant les programmes aux unités spécifiques de traitement SIMD du processeur CELL. L’utilisation efficace de la mémoire nécessite par ailleurs, à la fois une bonne exploitation des transferts et un arrangement optimal des données en mémoire. Nous avons développé un outil d’abstraction permettant de simplifier et d’automatiser les transferts et la synchronisation, CELL MPI. Cette expertise nous a permis de développer une méthodologie permettant de simplifier la mise en oeuvre parallèle optimisée de ces algorithmes. Nous avons ainsi conçu un outil de programmation parallèle à base de squelettes algorithmiques : SKELL BE. Ce modèle de programmation propose une solution originale de génération d’applications à base de métaprogrammation. Il permet, de manière automatisée, d’obtenir de très bonnes performances et de permettre une utilisation efficace de l’architecture, comme le montre la comparaison pour un ensemble de programmes test avec plusieurs autres outils dédiés à ce processeur. / This thesis aims to define a design methodology for high performance applications on future embedded processors. These architectures require an efficient usage of their different level of parallelism (fine-grain, coarse-grain), and a good handling of the inter-processor communications and memory accesses. In order to study this methodology, we have used a target processor which represents this type of emerging architectures, the Cell BE processor.We have also chosen a low level image processing application, the Harris points of interest detector, which is representative of a typical low level image processing application that is highly parallel. We have studied several parallelisation schemes of this application and we could establish different optimisation techniques by adapting the software to the specific SIMD units of the Cell processor. We have also developped a library named CELL MPI that allows efficient communication and synchronisation over the processing elements, using a simplified and implicit programming interface. This work allowed us to develop a methodology that simplifies the design of a parallel algorithm on the Cell processor.We have designed a parallel programming tool named SKELL BE which is based on algorithmic skeletons. This programming model providesan original solution of a meta-programming based code generator. Using SKELL BE, we can obtain very high performances applications that uses the Cell architecture efficiently when compared to other tools that exist on the market. Programmation parallèle Processeur CELL Traitement d’images Squelettes algorithmiques Calcul hautes performances Méta-programmation Processeur embarqué Parallel programming CELL processor Image processing Algorithmic skeletons High performance computing Meta-programming Embedded processors
42	A rapid design methodology for generating of parallel image processing applications and parallel architectures for smart camera / Méthodologie de prototypage rapide pour générer des applications de traitement d'images parallèles et architectures parallèles dédié caméra intelligente Chenini, Hanen 27 May 2014 (has links) Dû à la complexité des algorithmes de traitement d’images récents et dans le but d'accélérer la procédure de la conception des MPSoCs, méthodologies de prototypage rapide sont nécessaires pour fournir différents choix pour le programmeur de générer des programmes parallèles efficaces. Ce manuscrit présente les travaux menés pour proposer une méthodologie de prototypage rapide permettant la conception des architectures MPSOC ainsi que la génération automatique de système matériel / logiciel dédié un circuit reprogrammable (FPGA). Pour faciliter la programmation parallèle, l'approche MPSoC proposée est basée sur l’utilisation de Framework « CubeGen » qui permet la génération des différentes solutions envisageables pour réaliser des prototypes dans le domaine du traitement d’image. Ce document décrit une méthode basée sur le concept des squelettes générés en fonction des caractéristiques d'application afin d'exploiter tous les types de parallélisme des algorithmes réels. Un ensemble d’expérimentations utilisant des algorithmes courants permet d’évaluer les performances du flot de conception proposé équivalente à une architecture basé des processeurs hardcore et les solutions traditionnels basé sur cibles ASIC. / Due to the complexity of image processing algorithms and the restrictions imposed by MPSoC designs to reach their full potentials, automatic design methodologies are needed to provide guidance for the programmer to generate efficient parallel programs. In this dissertation, we present a MPSoC-based design methodology solution supporting automatic design space exploration, automatic performance evaluation, as well as automatic hardware/software system generation. To facilitate the parallel programming, the presented MPSoC approach is based on a CubeGen framework that permits the expression of different scenarios for architecture and algorithmic design exploring to reach the desired level of performance, resulting in short time development. The generated design could be implemented in a FPGA technology with an expected improvement in application performance and power consumption. Starting from the application, we have evolved our effective methodology to provide several parameterizable algorithmic skeletons in the face of varying application characteristics to exploit all types of parallelism of the real algorithms. Implementing such applications on our parallel embedded system shows that our advanced methods achieve increased efficiency with respect to the computational and communication requirements. The experimental results demonstrate that the designed multiprocessing architecture can be programmed efficiently and also can have an equivalent performance to a more powerful designs based hard-core processors and better than traditional ASIC solutions which are too slow and too expensive. Algorithmes de traitement d’images Conception des MPSoCs Prototypage rapide Programmes parallèles efficaces La génération automatique FPGA CubeGen Squelettes Types de parallélisme ASIC Image processing algorithms MPSoC designs Automatic design methodologies Efficient parallel programs CubeGen framework Parameterizable algorithmic skeletons All types of parallelism Traditional ASIC solutions
43	Squelettes algorithmiques pour la programmation et l'exécution efficaces de codes parallèles / Algorithmic skeletons for efficient programming and execution of parallel codes Legaux, Joeffrey 13 December 2013 (has links) Les architectures parallèles sont désormais présentes dans tous les matériels informatiques, mais les programmeurs ne sont généralement pas formés à leur programmation dans les modèles explicites tels que MPI ou les Pthreads. Il y a un besoin important de modèles plus abstraits tels que les squelettes algorithmiques qui sont une approche structurée. Ceux-ci peuvent être vus comme des fonctions d’ordre supérieur synthétisant le comportement d’algorithmes parallèles récurrents que le développeur peut ensuite combiner pour créer ses programmes. Les développeurs souhaitent obtenir de meilleures performances grâce aux programmes parallèles, mais le temps de développement est également un facteur très important. Les approches par squelettes algorithmiques fournissent des résultats intéressants dans ces deux aspects. La bibliothèque Orléans Skeleton Library ou OSL fournit un ensemble de squelettes algorithmiques de parallélisme de données quasi-synchrones dans le langage C++ et utilise des techniques de programmation avancées pour atteindre une bonne efficacité. Nous avons amélioré OSL afin de lui apporter de meilleures performances et une plus grande expressivité. Nous avons voulu analyser le rapport entre les performances des programmes et l’effort de programmation nécessaire sur OSL et d’autres modèles de programmation parallèle. La comparaison rigoureuse entre des programmes parallèles dans OSL et leurs équivalents de bas niveau montre une bien meilleure productivité pour les modèles de haut niveau qui offrent une grande facilité d’utilisation tout en produisant des performances acceptables. / Parallel architectures have now reached every computing device, but software developers generally lackthe skills to program them through explicit models such as MPI or the Pthreads. There is a need for moreabstract models such as the algorithmic skeletons which are a structured approach. They can be viewed ashigher order functions that represent the behaviour of common parallel algorithms, and those are combinedby the programmer to generate parallel programs. Programmers want to obtain better performances through the usage of parallelism, but the development time implied is also an important factor. Algorithmic skeletons provide interesting results in both those fields. The Orléans Skeleton Library or OSL provides a set of algorithmic skeletons for data parallelism within the bulk synchronous parallel model for the C++ language. It uses advanced metaprogramming techniques to obtain good performances. We improved OSL in order to obtain better performances from its generated programs, and extended its expressivity. We wanted to analyze the ratio between the performance of programs and the development effort needed within OSL and other parallel programming models. The comparison between parallel programs written within OSL and their equivalents in low level parallel models shows a better productivity for high level models : they are easy to use for the programmers while providing decent performances. Modèles de haut niveau, Squelettes algorithmiques Parallélisme quasi-synchrone Effort de programmation Expressivité Exceptions Distribution des données Homomorphismes High level programming models Algorithmic skeletons Bulk synchronous parallelism Development effort Expressivity Exceptions Data distribution Homomorphisms
44	Uso de saliências do contorno via esqueletização para recuperação de imagens Santos, Cristiane de Fátima dos 12 January 2007 (has links) Conselho Nacional de Desenvolvimento Científico e Tecnológico / Image retrieval is an offshoot of information retrieval, which has received growing attention. Within this new offshoot the area of shape-based retrieval has shown itself to be one of the most difficult tasks to perform successfully. It is therefore the purpose of this work to explore the main aspects of shape-based retrieval: the representation and the description of shapes, which aim at extracting the main shape forms, as well as the similarity measurements which are used in the comparison between two characteristic vectors which are the result of characteristic extraction. Various descriptors of different classes are covered giving a general view of how shape based retrieval can be carried out. When given further consideration these descriptors are able to point out some desirable aspects, with the invariance to geometric transformations being one of the principal ones. Therefore the descriptors are analyzed to their degree of invariance to transformations, also normalizations in the sense of making the descriptors invariant are analyzed. One new descriptor, contour saliences, in particular shows promising results as it is invariant to such transformations. For this reason the subject is widely discussed in this work, its retrieval is carried out through the use of skeletons being that each saliency is associated to an adjoining extremity, and this is obtained through the use of the image forest transform. A CBIR based on shape that uses salience is implemented and the final results are discussed. / A recuperação de imagens é um ramo oriundo da recuperação de informação que vem recebendo grande enfoque atualmente. E dentro deste novo ramo a recuperação baseada em formas é uma das tarefas mais difíceis. Assim, esse trabalho explora os principais aspectos de recuperação baseada em forma: a representação e a descrição de formas, que visam extrair as principais características da forma, e também medidas de similaridade, que são utilizadas na comparação entre dois vetores de característica resultantes da extração de características. Diversos descritores de diferentes classes são abordados dando uma visão geral de como pode ser realizada a recuperação baseada em forma. Considerando ainda os descritores, importantes aspectos podem ser apontados como sendo desejáveis, sendo a invariância a transformações geométricas um dos principais. Assim, os descritores são analisados quanto à sua invariância a transformações, e algumas normalizações no sentido de tornar os descritores invariantes também são analisadas. Um descritor novo e bastante promissor, por ser invariante a tais transformações, é o descritor saliências do contorno. Por isso este é amplamente discutido nesse trabalho. Sua obtenção é realizada através do uso de esqueletos sendo que cada saliência é associada à uma extremidade do mesmo, e este por sua vez é obtido através da transformada imagem floresta. Um CBIR baseado em forma utilizando saliências é implementado e seus resultados discutidos. / Mestre em Ciência da Computação Recuperação Imagem Recuperação de informação Transformada imagem floresta Saliências Esqueletos Processamento de imagens digitais Retrieval Image Information retrieval Image forest transform Saliences Skeletons Digital image processing
45	The Skeletal Amino Acid Composition of the Marine Demosponge Aplysina cavernicola Ueberlein, Susanne, Machill, Susanne, Niemann, Hendrik, Proksch, Peter, Brunner, Eike 07 May 2015 (has links) It has been discovered during the past few years that demosponges of the order Verongida such as Aplysina cavernicola exhibit chitin-based skeletons. Verongida sponges are well known to produce bioactive brominated tyrosine derivatives. We could recently demonstrate that brominated compounds do not exclusively occur in the cellular matrix but also in the skeletons of the marine sponges Aplysina cavernicola and Ianthella basta. Our measurements imply that these yet unknown compounds are strongly, possibly covalently bound to the sponge skeletons. In the present work, we determined the skeletal amino acid composition of the demosponge A. cavernicola especially with respect to the presence of halogenated amino acids. The investigations of the skeletons before and after MeOH extraction confirmed that only a small amount of the brominated skeleton-bound compounds dissolves in MeOH. The main part of the brominated compounds is strongly attached to the skeletons but can be extracted for example by using Ba(OH)2. Various halogenated tyrosine derivatives were identified by GC-MS and LC-MS in these Ba(OH)2 extracts of the skeletons. info:eu-repo/classification/ddc/540 ddc:540
46	Determination of the Halogenated Skeleton Constituents of the Marine Demosponge Ianthella basta Ueberlein, Susanne, Machill, Susanne, Schupp, Peter J., Brunner, Eike 17 July 2017 (has links) Demosponges of the order Verongida such as Ianthella basta exhibit skeletons containing spongin, a collagenous protein, and chitin. Moreover, Verongida sponges are well known to produce bioactive brominated tyrosine derivatives. We recently demonstrated that brominated compounds do not only occur in the cellular matrix but also in the skeletons of the marine sponges Aplysina cavernicola and I. basta. Further investigations revealed the amino acid composition of the skeletons of A. cavernicola including the presence of several halogenated amino acids. In the present work, we investigated the skeletal amino acid composition of the demosponge I. basta, which belongs to the Ianthellidae family, and compared it with that of A. cavernicola from the Aplysinidae family. Seventeen proteinogenic and five non-proteinogenic amino acids were detected in I. basta. Abundantly occurring amino acids like glycine and hydroxyproline show the similarity of I. basta and A. cavernicola and confirm the collagenous nature of their sponging fibers. We also detected nine halogenated tyrosines as an integral part of I. basta skeletons. Since both sponges contain a broad variety of halogenated amino acids, this seems to be characteristic for Verongida sponges. The observed differences of the amino acid composition confirm that spongin exhibits a certain degree of variability even among the members of the order Verongida. info:eu-repo/classification/ddc/540 ddc:540
47	A Comparative Analysis of Abnormal Bone Remodeling In 621 Female Skeletons Recovered From United Kingdom Burial Sites Ranging From Anglo-Saxon to Modern Temporal Periods Kocab, Ariana F. G. 04 May 2022 (has links) No description available. Archaeology Behavioral Sciences European History Forensic Osteology Human Remains Medieval History Middle Ages Pathology Physical Anthropology Womens Studies History Forensic Anthropology Anthropology bioarchaeology female skeletons United Kingdom Industrialization Degenerative Joint Disease Diffuse Idiopathic Skeletal Hyperostosis DJD DISH women's health
48	Dicomplemented Lattices / A Contextual Generalization of Boolean Algebras / Treillis Dicomplementes. Une Generalisation Contextuelle des Algebres de Boole. / Dikomplementaere Verbaende. Eine Kontextuelle Verallgemeinerung Boolescher Algebren Kwuida, Leonard 23 October 2004 (has links) (PDF) Das Ziel dieser Arbeit ist es die mathematische Theorie der Begriffsalgebren zu entwickeln. Wir betrachten dabei hauptsaechlich das Repraesentationsproblem dieser vor Kurzem eingefuehrten Strukturen. Motiviert durch die Suche nach einer geeigneten Negation sind die Begriffsalgebren entstanden. Sie sind nicht nur fuer die Philosophie oder die Wissensrepraesentation von Interesse, sondern auch fuer andere Felder, wie zum Beispiel Logik oder Linguistik. Das Problem Negationen geeignet einzufuehren, ist sicher eines der aeltesten der wissenschaftlichen oder philosophischen Gemeinschaft und erregt auch zur Zeit die Aufmerksamkeit vieler Wissenschaftler. Verschiedene Typen von Logik (die sich sehr stark durch die eigefuehrte Negation unterscheiden) unterstreichen die Wichtigkeit dieser Untersuchungen. In dieser Arbeit beschaeftigen wir uns hauptsaechlich mit der kontextuellen Logik, eine Herangehensweise der Formalen Begriffsanalyse, basierend auf der Idee, den Begriff als Einheit des Denkens aufzufassen. / The aim of this investigation is to develop a mathematical theory of concept algebras. We mainly consider the representation problem for this recently introduced class of structures. Motivated by the search of a &quot;negation&quot; on formal concepts, &quot;concept algebras&quot; are of considerable interest not only in Philosophy or Knowledge Representation, but also in other fields as Logic or Linguistics. The problem of negation is surely one of the oldest problems of the scientific and philosophic community, and still attracts the attention of many researchers. Various types of Logic (defined according to the behaviour of the corresponding negation) can attest this affirmation. In this thesis we focus on &quot;Contextual Logic&quot;, a Formal Concept Analysis approach, based on concepts as units of thought. Begriffsalgebren Boolesche Algebren Boolesche Begriffsalgebren Darstellungssatz Formale Begriffsanalyse Kongruenzen Kontextuelle Logik Merkmalexploration Negation Skeleton Strukturtheory Tripel Konstruktion Varietaeten dikomplementaere Verbae Boolean Concept Logic Boolean algebras Concept algebras Contextual logic Formal Concept Analysis Negation Representation attribute exploration congruence dicomplemented lattices skeletons structure theory triple construction varieties ddc:510 rvk:SK 130 Boolesche Algebra Formale Begriffsanalyse Strukturtheorie Verbandstheorie
49	Dicomplemented Lattices: A Contextual Generalization of Boolean Algebras Kwuida, Leonard 29 June 2004 (has links) Das Ziel dieser Arbeit ist es die mathematische Theorie der Begriffsalgebren zu entwickeln. Wir betrachten dabei hauptsaechlich das Repraesentationsproblem dieser vor Kurzem eingefuehrten Strukturen. Motiviert durch die Suche nach einer geeigneten Negation sind die Begriffsalgebren entstanden. Sie sind nicht nur fuer die Philosophie oder die Wissensrepraesentation von Interesse, sondern auch fuer andere Felder, wie zum Beispiel Logik oder Linguistik. Das Problem Negationen geeignet einzufuehren, ist sicher eines der aeltesten der wissenschaftlichen oder philosophischen Gemeinschaft und erregt auch zur Zeit die Aufmerksamkeit vieler Wissenschaftler. Verschiedene Typen von Logik (die sich sehr stark durch die eigefuehrte Negation unterscheiden) unterstreichen die Wichtigkeit dieser Untersuchungen. In dieser Arbeit beschaeftigen wir uns hauptsaechlich mit der kontextuellen Logik, eine Herangehensweise der Formalen Begriffsanalyse, basierend auf der Idee, den Begriff als Einheit des Denkens aufzufassen. / The aim of this investigation is to develop a mathematical theory of concept algebras. We mainly consider the representation problem for this recently introduced class of structures. Motivated by the search of a &quot;negation&quot; on formal concepts, &quot;concept algebras&quot; are of considerable interest not only in Philosophy or Knowledge Representation, but also in other fields as Logic or Linguistics. The problem of negation is surely one of the oldest problems of the scientific and philosophic community, and still attracts the attention of many researchers. Various types of Logic (defined according to the behaviour of the corresponding negation) can attest this affirmation. In this thesis we focus on &quot;Contextual Logic&quot;, a Formal Concept Analysis approach, based on concepts as units of thought. info:eu-repo/classification/ddc/510 ddc:510
50	Mänskliga kvarlevor från Eldslandet : Arkeologisk biografi om tre selknam-individer / Human remains from Tierra del Fuego : Archaeological biography of three Selknam-individuals Vera Oliva, Marcela January 2020 (has links) This work is an archaeological biography of three skeletons brought to Sweden from Tierra del Fuego in the late 1800s by scientist Otto Nordenskjöld and his Swedish expedition to the Magellan countries. These belonged to Selknam men killed by European farmers. In Sweden they were used in studies of comparative anatomy and as teaching and research material. They reflect the European colonial worldview of the 19th- and early 20th centuries, as well as a part of the colonial history of Patagonia and Tierra del Fuego. / Este trabajo es una biografía arqueológica sobre tres esqueletos traídos a Suecia desde Tierra del Fuego a fines de 1800, por el científico Otto Nordenskjöld y su expedición sueca a los países magallánicos. Estos pertenecían a hombres selknam, asesinados por estancieros europeos. En Suecia fueron utilizados en estudios de anatomía comparada y como material de enseñanza e investigación. Son un reflejo de la cosmovisión colonial europea de los siglos XIX y principios del XX, así como una parte de la historia colonial de Patagonia y Tierra del Fuego. colonialism indigenous people First Nations native-Americans Selknam Ona skeletons Patagonia Magellan Tierra del Fuego Nordenskjöld Chile Argentina kolonialism urinvånare urfolk ursprungsbefolkning selknam ona skelett Patagonia Magellan Eldslandet Tierra del Fuego Nordenskjöld Chile Argentina colonialismo pueblos originarios indígenas nativo americanos selknam ona esqueletos Patagonia Magallanes Tierra del Fuego Nordenskjöld Chile Argentina Humanities and the Arts Humaniora och konst Archaeology Arkeologi

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