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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Funkčnost neúplné - rozvedené rodiny ve vztahu k dítěti / The functionality of single - parent - divorced family in relation to a child

ELIŠKOVÁ, Zdeňka January 2008 (has links)
Every man enters the marriage and founds family with the idea of undoubtebly lucky and everlasting attachment. Unfortunately, it often happens, that sooner or later, a break-up of this idea occurs. During our lives, all of us face the break-up of marriage, respectively the family from our experience or from people around. The family break-up phenomenon is largely interconnected with the disintegration of traditional society and its transformation into modern industrial society that is set up with other values, other way of life, and legitimity of its autority. If the family does not meet its main objectives, it means important risk for the man affecting his sensitive spots by its dysfunction and afunction. All the members of family, children and adults are given their home by the family. The family nowadays, however, is considerably vulnerable due to changed social situation. The growing number of single-parent families, i.e. families where mother or father themselves take care of their children, is increasing with the number of divorces. The family has as unsubstitutable role in development and children´s bringing up. Instability of family life represents a serious threat in child socialization. The family system functioning is based on personality character, especially in parents, and that is why, when one of the parents fails in his/her basic role, the whole community is severely disturbed. In this regard, it is necessary to ask a lot of questions: How do single-parent families function? Are these families functional in relation to the child? What problems do these families meet? Is it necessary to help these families and how to do it? The last investigation into functioning of families was conducted in the 1980s by means of the Questionnaire of family functionality in relation to a child by Prof. Dunovský. In my thesis I decided to test the functionality of present families, and exactly single-parent {--} divorced families, which are constantly increasing in our society. Every fourth family in the Czech Republic is reported to be single-parent family. The aim of my thesis is, therefore, the findings of functionality level of these single-parent {--} divorced families.
32

[en] NONLINEAR VIBRATION AND STRUCTURE STABILITY ANALYSIS OF IMPERFECTION SENSITIVE ELEMENTS / [es] VIBRACIONES NO LINEALES E INESTABILIDADES DE ELEMENTOS EXTRUCTURALES SENCIBLES A IMPERFECCIONES / [pt] VIBRAÇÕES NÃO-LINEARES E INSTABILIDADES DE ELEMENTOS ESTRUTURAIS SENSÍVEIS A IMPERFEIÇÕES

DONALD MARK SANTEE 28 August 2001 (has links)
[pt] O objetivo desta tese é estudar os mecanismos de escape em sistemas estruturais sensíveis a imperfeições quando submetidos a certas classes de carregamentos dinâmicos, identificar os parâmetros que controlam o escape e criar critérios capazes de prever a fronteira de escape e a perda de estabilidade da estrutura no espaço dos parâmetros de controle. Isto permitirá um melhor entendimento dos processos de perda de estabilidade e servirá de base para o cálculo e controle da integridade dessas estruturas. Após a descrição dos fenômenos que podem ocorrer na dinâmica dessa classe de estruturas, são testados e adaptados alguns critérios existentes na literatura, que verificam a estabilidade de uma estrutura a partir do conhecimento dos parâmetros de controle. Em seguida estuda-se a evolução da estabilidade global do conjunto das soluções medida pela área da bacia de atração, e pelas características de sua fronteira. Desenvolvem-se expressões gerais para o critério de Melnikov, e mostra-se, a partir de perturbações aleatórias nos parâmetros de controle e na força externa, que essas expressões podem ser tomadas como um limite inferior para o carregamento de escape e conseqüentemente como uma contribuição para o desenvolvimento de critérios de projeto. Verifica-se também que os valores obtidos pelos critérios de escape podem ser tomados como limites superiores para o valor da força de escape. / [en] The purpose of this thesis is to study the escape mechanisms in imperfection sensitive structural systems under certain dynamical loading conditions. Other objectives are to identify the parameters that control the escape phenomenon and to create some criteria capable of predicting the escape boundary and the structures stability in the control parameters space. This will allow a better understanding of the stability loss process and can serve as a basis to the integrity control and design of these structures. After a description of the phenomena that can occur in the dynamics of this class of structures, some predictive criteria, found in literature, that verify the structure stability based on the control parameters knowledge, are adapted and tested. Following is a study of the evolution of the global stability of the set of solutions measured by the basin of attraction area, and by the characteristics of its boundary. Some general expressions for the Melnikov criterion are developed, and it is shown by randomly perturbing the control parameters and the external force, that these expressions can be taken as a lower bound for the escape load, and consequently as a contribution to the development of design criteria. It is also observed that the values obtained by the escape criteria can be taken as an upper bound for the values of the escape force. / [es] EL objetivo de esta tesis es estudiar los mecanismos de escape en sistemas extructurales que son sensibles a imperfecciones cuando son sometidos a ciertas clases de cargas dinámicas. Outro objetivo es identificar los parámetros que controlan el escape y crear criterios capaces de preveer la frontera de escape y la pérdida de estabilidad de la extructura en el espacio de los parámetros de control. Esto permitirá una mejor comprensión de los procesos de pérdida de estabilidad y servirá de base para el cálculo y control de la integridad de esas extructuras. Después de describir los fenómenos que pueden ocurrir en la dinámica de esta clase de extructuras, se prueban y adaptan algunos criterios existentes en la literatura, que verifican la estabilidad de una extructura a partir del conocimiento de los parámetros de control. Seguidamente, se estudia la evolución de la estabilidad global del conjunto de las soluciones, se dearrollan expresiones generales para el criterio de Melnikov, y se muestra, a partir de perturbaciones aleatorias en los parámetros de control y en la fuerza externa, que esas expresiones pueden ser tomadas como límite inferior para la carga de escape y conseqüentemente como una contribución para el desarrollo de criterios de proyecto. Se verifica también que los valores obtenidos por los criterios de escape pueden ser tomados como límites superiores para el valor de la fuerza de escape.
33

Media Velocity Considerations in Pleated Air Filtration

Schousboe, Frederik Carl 21 March 2017 (has links)
Asset protection in the form of fluid filtration makes up an ever-increasing part of the civilized and industrialized world. Fluid filtration applications in the conditioned environment and life sciences are affording the world’s population a chance to better realize their potential, while industrial applications help ensure that high demand processes can be carried out safely, reliably, and effectively. In the present work, a tool has been developed, using the computational fluid dynamics package FLUENT, to allow the designer to better predict the magnitude of geometric imperfections within a given pleat configuration. Pleated rectangular filters, intended to improve the quality of air for human occupants, with a U-shaped pleat form have been chosen as the focus of this study. A simulation study is developed to investigate the maximum local velocity normal to the filtration surface and to characterize the magnitude of the pleatwise velocity distribution across a range of pleated geometries and flow conditions. The geometry of the U-shaped pleat form can be characterized by, amongst other parameters, the width of the pleat channel, the overall height of the individual pleat, as well as the thickness of the filtration medium. The various geometries of the current study were developed by changing the width of the pleat channel, as well as the channel height, while keeping the medium thickness constant throughout. Changing the width of the pleat channel allows the designer to achieve varying pleat densities, expressed as a number of pleats along a one inch section of the overall pleated pack. Pleat densities of 6.5, 7, 7.5, 8, and 8.5 pleats per inch are considered in the current study. Pleat heights of 1.0, 0.75, and 0.50 inches are also investigated in the current study. Furthermore, the filter velocity can be characterized by the free stream velocity at the face of the filter pack, termed the face velocity, and by the velocity of the fluid at the interface with the filtration medium, referred to as media velocity. In the present work, the face velocity was adjusted in each case to achieve the desired media velocities across the study, which are 10.5, 9.0, 7.5, and 6.0 feet per minute. In an effort to more clearly communicate the results of the study, the results are presented in the form of a non-dimensionalized plots which present the designer with a way to quickly gauge the effect of pleat geometry on maximum velocity. Additionally, two tools are presented to aid the designer in more accurately predicting the maximum filtration velocity. These tools are then evaluated for effectiveness using the method of absolute relative percent error. The assumption of uniform flow through the filtration media leads to an average absolute relative percent error of 27%. The first tool the reader is presented with is a simple correction factor which predicts the maximum filtration velocity with an average absolute relative percent error of 10% over the study domain. The second tool, which takes a slightly more complicated y-intercept form, characterizes the maximum filtration velocity as a function of average velocity and aspect ratio. This approach further reduces the average absolute relative percent error to 4%. The results of the simulation herein are successfully employed to develop a set of simple yet effective tools that allow the filter designer to more accurately predict maximum velocities through a pleated air filter.
34

Avaliação da política de desoneração da folha de pagamentos da indústria de transformação: uma abordagem a partir de estimativas de imperfeições de mercado / Policy Evaluation using Market Imperfection Estimates: the payroll tax exemption for Brazilian manufacturing sector

Leandro Garcia Meyer 08 February 2017 (has links)
A presente pesquisa teve como objetivo avaliar a política de desoneração da folha de pagamentos da indústria de transformação por meio de uma abordagem metodológica alternativa e complementar ao método de diferenças em diferenças, que é usualmente utilizado em tais casos. Este tema é relevante na medida em que a perda de dinamismo do setor industrial brasileiro tem feito ressurgir o debate a respeito da hipótese de desindustrialização. Ainda que a ocorrência ou não deste fenômeno não seja consensual, este cenário levou o governo a retomar o uso de políticas industriais desde 2004, sendo a desoneração da folha de pagamentos uma das medidas mais relevantes tomadas recentemente para promover a recuperação do setor industrial. A medida ambiciona reduzir os custos trabalhistas para impulsionar o emprego e a produção do setor, além de melhorar sua competitividade, e se destaca pela grande quantidade de recursos empregada: entre 2011 e 2013 a renúncia fiscal associada à pollítica foi de R$ 20 bilhões. Para avaliar esta medida, a presente pesquisa considerou a tributação sobre a mão de obra como uma fonte de imperfeição no mercado de trabalho, a qual é estimada por meio da metodologia proposta por Petrin e Sivadasan (2013). Ao considerar que a política reduz tais imperfeições, foi possível estimar seu efeito no nível de emprego da indústria por meio de extensões ao modelo proposto pelos autores. Foram utilizados microdados da Pesquisa Industrial Anual (PIA-Empresa) em nível de firma entre os anos de 1996 e 2011. A variação no emprego das indústrias beneficiadas pela medida foi de apenas 0,84%, considerando somente as indústrias inicialmente beneficiadas pela política. Os efeitos da política aumentaram com sua expansão, o que ocorreu não somente como consequência do aumento no número de indústrias beneficiadas, mas também porque a medida passou a contemplar indústrias cujas elasticidades do emprego em relação aos tributos são maiores, fazendo com que o aumento no nível de emprego passasse para 5,14%. Além disso, os resultados mostraram que a variação no nível de emprego é maior para o trabalho do tipo blue collar do que para o trabalho do tipo white collar. Isto está em acordo com a teoria econômica sobre o mercado de trabalho porque um tipo de trabalho com atribuições mais específicas e que envolve maior aquisição de conhecimentos, como é o trabalho white collar, deve ser mais afetado por outras variáveis que não os tributos. / The Brazilian government and policy makers have been concerned about the industrial performance lately, which made industrial policies recover its relevance in the political agenda since 2004. One of the most important of such policies was the payroll tax exemption to some industries, which was created to reduce labor costs, and to stimulate the Brazilian industry production, employment and competitiveness. The high coverage of this policy resulted in an important reduction in the Social Security contribution: the policy has already reduced the contribution in BRL20 billion from 2011 to 2013. Both the program expenses and the perceived need to increase Brazilian industrial competitiveness are reasons to carry out a formal empirical evaluation. However, there are many factors to control in order to identify the policy effects by the Randomized Control Trials, which makes this approach hardly suitable. The methodology to estimate market imperfections developed by Petrin e Sivadasan (2013) is helpful in this case. These estimates represent any phenomena that moves the market away from competitive equilibrium, such as mark ups, firing and hiring costs, capital adjustment costs, taxes and subsides. Therefore, the payroll tax exemption can be treated as a decrease in the gap for industrial sector labor market equilibrium, and this relationship between policy and market imperfections allows the policy effects identification. The variables used are from the Annual Industrial Research - Enterprise (\"PIA - Empresa\"), and were studied at the firm level for the period between 1996 and 2011. The results suggest that the policy increased the employment level in 0.84% considering only industries selected at the policy\'s first stage. The estimated effect on employment level increases to 5.14% considering also industries benefited by the policy after its expansions, which is related to higher elasticity of employment with respect to taxes for the industries included. Besides that, results show that most of the jobs created are blue collar jobs, which is in accordance with previous expectations since white collar jobs usually requires more skilled workers and, therefore, reacts more to other factors than taxes.
35

Standardizace a harmonizace znaleckých postupů při analýze vad a poruch novostaveb bytových jednotek / Standardization and harmonization of the expert process analyses of the new-built flats

Nováčková, Jana January 2009 (has links)
Legal rules and regulations, which are engaged in forensic engineering including expert evidence’s requirements, are because of the difference of this sphere very universal and common. Due to this situation, legal orders and regulations can not standardize and harmonize expert procedures for particular branches or their specific parts. The Dissertation thesis is focused on a elaboration of the methodology procedure for expert evidence’s elaborations, which analyze defects and imperfections in new-built flats.
36

Nonlinear Stability Analysis of Frame-Type Structures with Random Geometric Imperfections Using a Total-Lagrangian Finite Element Formulation

Warren, J. E. Jr. 21 January 1997 (has links)
With the increasing use of lightweight frame-type structures that span long distances, there is a need for a method to determine the probability that a structure having random initial geometric imperfections will become unstable at a load less than a specified fraction of the perfect critical load. The overall objective of this dissertation is to present such a method for frame-type structures that become unstable at limit points. The overall objective may be broken into three parts. The first part concerns the development of a three-dimensional total Lagrangian beam finite element that is used to determine the critical load for the structure. The second part deals with a least squares method for modeling the random initial imperfections using the mo de shapes from a linear buckling analysis, and a specified maximum allowable magnitude for the imperfection at any imperfect node in the structure. The third part deals with the calculation of the probability of failure using a combined response surface/ first-order second-moment method. Numerical results are presented for two example problems, and indicate that the proposed method is reasonably accurate. Several problems with the proposed method were noted during the course of this work and are discussed in the final chapter. / Ph. D.
37

Imperfect flâneurs : anti-heroes of modern life

Ng, Simon Yiu-Tsan 08 1900 (has links)
Cette thèse commence comme une simple question en réponse au modèle du « parfait flâneur » que Baudelaire a élaboré dans Le peintre de la vie moderne (1853): un flâneur peut-il être imparfait? Je suggère trois interprétations possibles du mot « imparfait ». Il permet d’abord de sortir le flâneur du strict contexte du Paris du dix-neuvième siècle et permet des traductions imparfaites de personnages dans d’autres contextes. Ensuite, le flâneur déambule dans la dimension « imparfaite » de l’imagination fictionnelle – une dimension comparable à l’image anamorphique du crâne dans la peinture Les ambassadeurs de Holbein. Enfin, il réfère à l’imparfait conjugué, « l’imparfait flâneur » peut rappeler le personnage antihéroïque de l’humain dont l’existence est banale et inachevée, comme la phrase « il y avait ». Ces trois visions contribuent à la réinterprétation du flâneur dans le contexte de la fin du vingtième siècle. Mon hypothèse est que l’expérience urbaine du flâneur et la flânerie ne sont possibles que si l’on admet être imparfait(e), qu’on accepte ses imperfections et qu’elles ne nous surprennent pas. Quatre études de romans contemporains et de leurs villes respectives forment les principaux chapitres. Le premier étudie Montréal dans City of forgetting de Robert Majzels. J’examine les façons par lesquelles les personnages itinérants peuvent être considérés comme occupant (ou en échec d’occupation) du Montréal contemporain alors qu’ils sont eux-mêmes délogés. Quant au deuxième chapitre, il se concentre sur le Bombay de Rohinton Mistry dans A fine balance. Mon étude portera ici sur la question de l’hospitalité en relation à l’hébergement et au « dé-hébergement » des étrangers dans la ville. Le troisième chapitre nous amène à Hong-Kong avec la série Feituzhen de XiXi. Dans celle-ci, j’estime que la méthode spéciale de la marelle apparait comme une forme unique de flânerie imparfaite. Le quatrième chapitre étudie Istanbul à travers The black book d’Orhan Pamuk. Inspiré par les notions de « commencement » d’Edward Saïd, mon argumentaire est construit à partir de l’interrogation suivante : comment et quand commence une narration? En lieu de conclusion, j’ai imaginé une conversation entre l’auteur de cette thèse et les personnages de flâneurs imparfaits présents dans les différents chapitres. / This dissertation begins with a simple question in response to “the perfect flâneur” model that Baudelaire elaborated in his 1853 essay “The Painter of Modern Life”: can a flâneur be imperfect? I suggest three possible inferences behind the word “imperfect.” First, it should liberate the flâneur from the strict context of nineteenth-century Paris, and allows for imperfect translations of the figure into other urban contexts. Second, the flâneur also strolls in the “imperfect” dimension of fictional imagination, a dimension comparable to the anamorphic skull in Holbein’s painting The Ambassadors. Third, in the grammatical meaning of imperfect verb tenses, “imperfect flâneur” can also refer to the anti-heroic figure of the living, whose existence remains incomplete and mundane as in the phrase “it was.” All three implications contribute to the reinterpretation of the flâneur in late twentieth-century contexts. My premise is that to experience the city as a flâneur, or to make flânerie possible in the city, one should concede being imperfect, anticipate imperfections, and come to terms with them. Four in-depth studies of contemporary novels and their respective cities constitute the main chapters. Chapter One reads Robert Majzels’s City of Forgetting and Montreal. I examine the ways in which homeless characters could be said to occupy – or, fail to occupy – contemporary Montreal from their dislodged position. Chapter Two focuses on Rohinton Mistry’s A Fine Balance and Bombay. My reading evolves around the question of hospitality in relation to the accommodation and un-accommodation of strangers in the city. Chapter Three brings us to XiXi’s Feituzhen series and Hong Kong: I address the special method of hopscotching as a unique form of imperfect flânerie in XiXi’s works. In Chapter Four, I study Orhan Pamuk’s The Black Book and Istanbul. Inspired by Edward Said’s notions of beginning, I frame my argument with the enquiry: how and when does a narrative begin? In lieu of Conclusion, I imagined a conversation between the writing subject of this dissertation and the imperfect flâneurs featured in each chapter.
38

Dialogue graphique intelligent, fondé sur une ontologie, pour une prothèse de mémoire / Smart graphical dialogue, based on an ontology, for a memory prosthesis

Ghorbel, Fatma 10 July 2018 (has links)
Dans le cadre de cette thèse, nous proposons une prothèse de mémoire « intelligente », appelée CAPTAIN MEMO, destinée aux malades d’Alzheimer, pour pallier leurs problèmes mnésiques. Cette prothèse est basée sur l’ontologie temporelle, floue et multilingue appelée MemoFuzzyOnto.Cette prothèse offre des interfaces accessibles à cette classe particulière d’utilisateurs. Nous proposons, pour mettre en œuvre ces interfaces, une méthodologie de conception appelée InterfaceToAlz pour concevoir des interfaces accessibles aux malades d’Alzheimer, et qui offre un guide de 146 bonnes pratiques ergonomiques. De plus, nous proposons un outil de visualisation d’ontologies appelé Memo Graph qui génère un graphe dont la visualisation et la manipulation sont accessibles aux malades d’Alzheimer. Cette proposition est motivée par le fait que CAPTAIN MEMO a besoin de générer et d’éditer le graphe de la famille et de l’entourage du patient, à partir de l’ontologie MemoFuzzyOnto qui structure sa base de connaissances. Memo Graph est fondé sur notre guide de bonnes pratiques ergonomiques et notre approche, appelée Incremental Key-Instances Extraction and Visualisation, qui permet une extraction et une visualisation incrémentale du résumé des assertions ABox de l’ontologie. Il supporte également la visualisation des données ouvertes liées (Linked Data) et le passage à l’échelle. Par ailleurs, nous proposons, dans le cadre de cette thèse, une typologie de l’imperfection des données saisies (principalement due à la discordance mnésique provoquée par la maladie), et une méthodologie pour permettre à CAPTAIN MEMO d’être tolérante à la saisie des données fausses. Nous proposons un modèle d’évaluation de la crédibilité et une approche, nommée Data Believability Estimation for Applications to Alzheimer Patients, permettant d’estimer qualitativement et quantitativement la crédibilité de chaque donnée saisie. Enfin, pour que CAPTAIN MEMO soit tolérante à la saisie des intervalles temporels imprécis nous proposons deux approches : l’une basée sur un environnement précis et l’autre basée sur un environnement flou. Dans chacune des deux approches, nous étendons l’approche 4D-fluents pour représenter les intervalles temporels imprécis et les relations temporelles qualitatives, puis nous étendons l’algèbre d’Allen pour prendre en compte les intervalles imprécis dans le cadre de notre ontologie MemoFuzzyOnto. Nos contributions sont implémentées et évaluées. Nous avons évalué l’accessibilité de ses interfaces utilisateurs, le service de CAPTAIN MEMO qui a pour but de stimuler la mémoire du patient, notre approche pour l’estimation quantitative de la crédibilité des données saisies ainsi que la visualisation du graphe générée à l’aide de Memo Graph. Nous avons également évalué la performance de Memo Graph et son utilisabilité par des experts du domaine. / In the context of this thesis, we propose a “smart” memory prosthesis, called CAPTAIN MEMO, to help Alzheimer’s disease patients to palliate mnesic problems. It is based on a temporal, fuzzy and multilingual ontology named MemoFuzzyOnto. It provides accessible user interfaces to this demographic. To design these interfaces, we propose a methodology named InterfaceToAlz which serves as an information base for guiding and evaluating the design of user interfaces for Alzheimer’s disease patients. It identifies 146 design guidelines.Besides, we propose an ontology visualization tool called Memo Graph which offers an accessible and understandable visualization to Alzheimer’s disease patients. In fact, in the context of CAPTAIN MEMO, there is a need to generate the patient entourage/family tree from its personal data structured according to MemoFuzzyOnto. Memo Graph is based on our design guidelines and our approach, named Incremental Key-Instances Extraction and Visualisation, to extract and visualize descriptive instance summarizations from a given ontology and generate “summary instance graphs” from the most important data. It supports Linked Data visualization and scaling.Furthermore, we propose a typology of the imperfection of the data entered (mainly due to the memory discordance caused by this disease), and a methodology to allow false data entry. We propose a believability model and an approach called Data Believability Estimation for Applications to Alzheimer Patients to estimate qualitatively and quantitatively the believability of each data entered. Finally, CAPTAIN MEMO allows imprecise time intervals entry. We propose two approaches: a crisp-based approach and a fuzzy-based approach. The first one uses only crisp standards and tools and is modeled in OWL 2. The second approach is based on fuzzy sets theory and fuzzy tools and is modeled in Fuzzy-OWL 2. For the two approaches, we extend the 4D-fluents model to represent imprecise time intervals and qualitative interval relations. Then, we extend the Allen’s interval algebra to compare imprecise time interval in the context of MemoFuzzyOnto. Our contributions are implemented and evaluated. We evaluated the service of CAPTAIN MEMO which has the aim to stimulate the patient’s memory, the accessibility of its user interfaces, the efficiency of our approach to estimate quantitatively the believability of each data entered and the visualization generated with Memo Graph. We also evaluated Memo Graph with domain expert users.
39

Imperfection, temps et espace : modélisation, analyse et visualisation dans un SIG archéologique

De Runz, Cyril 25 November 2008 (has links) (PDF)
Face aux enjeux urbains actuels, à la patrimonialisation des ressources archéologiques et grâce au développement de l'informatique, l'utilisation des systèmes d'information géographique devient essentielle pour l'exploitation des données archéologiques. Pour cela, il s'avère nécessaire de modéliser, d'analyser et de visualiser l'information archéologique en prenant en considération l'aspect temporel et spatial mais surtout les imperfections des données archéologiques. Cette thèse élabore une démarche globale pour l'utilisation de données spatiotemporelles imparfaites dans un SIG archéologique. Cette démarche contribue à une meilleure gestion de celles-ci tant pour leur représentation que pour leur traitement. Dans cette démarche scientifique, les concepts théoriques de taxonomie de l'imperfection et de représentation des données imparfaites permettent d'abord la modélisation des données archéologiques. Ce mémoire propose ensuite des méthodes d'analyse des données d'un SIG archéologique. La spécificité de leur caractère temporel implique une gestion plus flexible du temps par un indice quantifiant l'antériorité. L'aspect lacunaire de l'information est aussi considéré à travers une méthode d'interrogation sous critère de forme. Enfin, des outils originaux d'exploration et de visualisation de données archéologiques sont exposés afin de mieux définir les éléments les plus représentatifs. Par une approche interdisciplinaire liant informatique et géographie, cette thèse développe une vision transversale autour de la gestion des connaissances imparfaites dans le temps et l'espace. Cette approche est illustrée par l'utilisation de données archéologiques dans un SIG.
40

Fusion de connaissances imparfaites pour l'appariement de données géographiques : proposition d'une approche s'appuyant sur la théorie des fonctions de croyance

Olteanu, Ana-Maria 24 October 2008 (has links) (PDF)
De nos jours, il existe de nombreuses bases de données géographiques (BDG) couvrant le même territoire. Les données géographiques sont modélisées différemment (par exemple une rivière peut être modélisée par une ligne ou bien par une surface), elles sont destinées à répondre à plusieurs applications (visualisation, analyse) et elles sont créées suivant des modes d'acquisition divers (sources, processus). Tous ces facteurs créent une indépendance entre les BDG, qui pose certains problèmes à la fois aux producteurs et aux utilisateurs. Ainsi, une solution est d'expliciter les relations entre les divers objets des bases de données, c'est-à-dire de mettre en correspondance des objets homologues représentant la même réalité. Ce processus est connu sous le nom d'appariement de données géographiques. La complexité du processus d'appariement fait que les approches existantes varient en fonction des besoins auxquels l'appariement répond, et dépendent des types de données à apparier (points, lignes ou surfaces) et du niveau de détail. Nous avons remarqué que la plupart des approches sont basées sur la géométrie et les relations topologiques des objets géographiques et très peu sont celles qui prennent en compte l'information descriptive des objets géographiques. De plus, pour la plupart des approches, les critères sont enchaînés et les connaissances sont à l'intérieur du processus. Suite à cette analyse, nous proposons une approche d'appariement de données qui est guidée par des connaissances et qui prend en compte tous les critères simultanément en exploitant à la fois la géométrie, l'information descriptive et les relations entre eux. Afin de formaliser les connaissances et de modéliser leurs imperfections (imprécision, incertitude et incomplétude), nous avons utilisé la théorie des fonctions de croyance [Shafer, 1976]. Notre approche d'appariement de données est composée de cinq étapes : après une sélection des candidats, nous initialisons les masses de croyance en analysant chaque candidat indépendamment des autres au moyen des différentes connaissances exprimées par divers critères d'appariement. Ensuite, nous fusionnons les critères d'appariement et les candidats. Enfin, une décision est prise. Nous avons testé notre approche sur des données réelles ayant des niveaux de détail différents représentant le relief (données ponctuelles) et les réseaux routiers (données linéaires)

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