1,720,970 research outputs found
Contribution à l'optimisation en conception préliminaire de produit
Full text linkThe optimization in product design is a high added-value activity. This is all the more important when it is performed at the early stages of the design process. The work presented in this thesis is placed in this context. It proposes adapted decision making tools in preliminary design following two criteria: whether or not the model contains functionals, and whether it takes into considerations the uncertainties. A method based on interval arithmetic and constraint propagation allowing to perform deterministic global optimization is introduced. This method allows handling optimization models without functionals and without considering uncertainties. A reformulation that permits to improve the algorithm convergence is introduced. A stochastic optimization method based on particular swarms is introduced in order to handle higher dimensional problems. A new constraint handling mechanism is introduced and tested on engineering problems. This algorithm has also been extended to design problems with ordinary differential equations constraints. In order to consider uncertainties, a robust optimization method is introduced. It combines a stochastic optimization method with an uncertainty propagation method called PoV. An extension of PoV to models involving functionals is introduced.L'optimisation en conception de produit constitue une activité à forte valeur ajoutée en entreprise. Ceci est d'autant plus important qu'elle est appliquée dans les premières phases du processus de conception. Les travaux dans cette thèse se placent dans ce contexte et proposent des outils adaptés d'aide à la décision en pré-dimensionnement de produits suivant deux critères: présence ou non de fonctionnelles dans le modèle, prise en compte ou non des incertitudes dans le modèle. Une méthode à base de calcul d'intervalles et de propagation de contraintes qui permet de faire de l'optimisation déterministe est introduite. Cette méthode permet de traiter les modèles d'optimisation sans fonctionnelles et sans prise en compte d'incertitudes. Une reformulation qui permet d'améliorer la convergence de l'algorithme est introduite. Une méthode d'optimisation stochastique à base d'essaims particulaires est présentée pour traiter les modèles de plus grande dimension. Un nouveau mécanisme de gestion de contraintes est introduit. Cet algorithme a aussi été étendu pour traiter les problèmes de conception en présence de contraintes du type équations différentielles. Afin de traiter les incertitudes dans les modèles, une méthode d'optimisation robuste est présentée. Elle combine un algorithme d'optimisation stochastique avec une méthode de propagation d'incertitude (PoV). Cette méthode de propagation d'incertitude est étendu aux modèles incluant des fonctionnelles
Contribution to optimization in product's preliminary design
No full textL'optimisation en conception de produit constitue une activité à forte valeur ajoutée en entreprise. Ceci est d'autant plus important qu'elle est appliquée dans les premières phases du processus de conception. Les travaux dans cette thèse se placent dans ce contexte et proposent des outils adaptés d'aide à la décision en pré-dimensionnement de produits suivant deux critères: présence ou non de fonctionnelles dans le modèle, prise en compte ou non des incertitudes dans le modèle. Une méthode à base de calcul d'intervalles et de propagation de contraintes qui permet de faire de l'optimisation déterministe est introduite. Cette méthode permet de traiter les modèles d'optimisation sans fonctionnelles et sans prise en compte d'incertitudes. Une reformulation qui permet d'améliorer la convergence de l'algorithme est introduite. Une méthode d'optimisation stochastique à base d'essaims particulaires est présentée pour traiter les modèles de plus grande dimension. Un nouveau mécanisme de gestion de contraintes est introduit. Cet algorithme a aussi été étendu pour traiter les problèmes de conception en présence de contraintes du type équations différentielles. Afin de traiter les incertitudes dans les modèles, une méthode d'optimisation robuste est présentée. Elle combine un algorithme d'optimisation stochastique avec une méthode de propagation d'incertitude (PoV). Cette méthode de propagation d'incertitude est étendu aux modèles incluant des fonctionnelles.The optimization in product design is a high added-value activity. This is all the more important when it is performed at the early stages of the design process. The work presented in this thesis is placed in this context. It proposes adapted decision making tools in preliminary design following two criteria: whether or not the model contains functionals, and whether it takes into considerations the uncertainties. A method based on interval arithmetic and constraint propagation allowing to perform deterministic global optimization is introduced. This method allows handling optimization models without functionals and without considering uncertainties. A reformulation that permits to improve the algorithm convergence is introduced. A stochastic optimization method based on particular swarms is introduced in order to handle higher dimensional problems. A new constraint handling mechanism is introduced and tested on engineering problems. This algorithm has also been extended to design problems with ordinary differential equations constraints. In order to consider uncertainties, a robust optimization method is introduced. It combines a stochastic optimization method with an uncertainty propagation method called PoV. An extension of PoV to models involving functionals is introduced
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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