Dans cette thèse, nous nous intéressons aux proportions analogiques dans le contexte des bases de données relationnelles. Les proportions analogiques permettent de lier quatre éléments dans une relation du type ''A est à B ce que C est à D''. Par exemple, « Paris est à la France ce que Rome est à l'Italie ». Nous avons étudié le problème de la prédiction de valeurs manquantes dans une base de données en utilisant les proportions analogiques. Un algorithme de classification fondé sur les proportions analogiques a été modifié afin de résoudre ce problème. Puis, nous avons étudié les propriétés des éléments appartenant à l'ensemble d'apprentissage des classificateurs analogiques fréquemment exploités pour calculer la prédiction. Ceci nous a permis de réduire considérablement la taille de cet ensemble par élimination des éléments peu pertinents et par conséquent, de diminuer les temps d'exécution de ces classificateurs. La deuxième partie de la thèse a pour objectif de découvrir de nouveaux patrons basés sur la relation d'analogie, i.e., des parallèles, dans les bases de données. Nous avons montré qu'il est possible d'extraire ces patrons en s'appuyant sur des approches de clustering. Les clusters produits par de telles techniques présentent aussi un intérêt pour l'évaluation de requêtes recherchant des patrons d'analogie dans les bases de données. Dans cette perspective, nous avons proposé d'étendre le langage de requêtes SQL pour pouvoir trouver des quadruplets d'une base de données satisfaisant une proportion analogique. Nous avons proposé différentes stratégies d'évaluation pour de telles requêtes, et avons comparé expérimentalementleurs performances. / In this thesis, we are interested in the notion of analogical proportions in a relational database context. An analogical proportion is a statement of the form “A is to B as C is to D”, expressing that the relation beween A and B is the same as the relation between C and D. For instance, one may say that “Paris is to France as Rome is to Italy”. We studied the problem of imputing missing values in a relational database by means of analogical proportions. A classification algorithm based on analogical proportions has been modified in order to impute missing values. Then, we studied how analogical classifiers work in order to see if their processing could be simplified. We showed how some typeof analogical proportions is more useful than the others when performing classification. We then proposed an algorithm using this information, which allowed us to considerably reduce the size of the training set used by the analogical classificationalgorithm, and hence to reduce its execution time. In the second part of this thesis, we payed a particular attention to the mining of combinations of four tuples bound by an analogical relationship. For doing so, we used several clustering algorithms, and we proposed some modifications to them, in order tomake each obtained cluster represent a set of analogical proportions. Using the results of the clustering algorithms, we studied how to efficiently retrieve the analogical proportions in a database by means of queries. For doing so, we proposed to extend the SQL query language in order to retrieve from a database the quadruples of tuples satisfying an analogical proportion. We proposed severalquery evaluation strategies and experimentally compared their performances.

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Many studies on feature-based search have found that color is preferentially used as a guiding feature. Most of these studies have utilized simple stimuli and the several studies that utilized real-world objects have been limited by the subjective color classification of objects. The current set of studies examined how search was guided by color and color proportions in real-world objects using color histograms to objectively classify color. To bridge the gap between simple stimuli and real-world objects, the first experiment examined how different color compositions in color conjunctions affected search. In the second experiment, real-world objects were objectively classified according to their primary color as determined by a color histogram, which was used to predict behavior. Finally, in the third experiment, real-world objects were classified by both their primary and secondary colors, which again, was used to predict behavior. Across three experiments the results demonstrated that search was guided by both colors of the target and there was more guidance to objects that matched the target's primary color than the target's secondary color. The results showed that theories derived from studying simple stimuli can be applied to more complex stimuli and tools developed in computer vision research can be used as an objective measure.

Ma pratique en art se conçoit uniquement en peinture. Elle est orientée vers l’abstraction où je travaille la forme et la couleur exclusivement liées à mes états émotionnels. Ma préoccupation première tourne autour du principe de l’équilibre pictural qui consiste à répartir les éléments visuels dans un tableau de manière à harmoniser la composition et les proportions. Afin d’arriver à ce stade, j’équilibre mes peintures selon leurs éléments plastiques. Chacune des composantes picturales interagit avec ses voisines, nécessitant ainsi une préoccupation constante du poids visuel de celles-ci. Ce poids s’établit en termes de pesanteur (légèreté/lourdeur), au niveau des formes (ovale/cubique), des couleurs (claire/foncé) et des espaces (allégé, surchargé). L’aspect de dualités entre deux notions plastiques (transparence/opacité, chaud/froid, traits/masses) est aussi présent dans mon travail pour créer ce que j’appelle des tensions spatiales. Ces rapports de dualité complètent, avec l’équilibre, le dynamisme visuel qui se construit devant mes yeux. Composées d’un amas de masses de couleurs de différentes grosseurs et de formes aléatoires, mes peintures sont créées en majorité par des traces de vitesse. Travailler avec la peinture acrylique est un avantage puisqu’elle sèche très vite et qu’elle me permet de venir camoufler, juxtaposer, altérer et foncer une ancienne tache sans que les couleurs ne se mélangent. La conception de mes toiles est donc un processus d’accumulation et de superposition de masses ou de formes colorées qui se conçoit rapidement et instinctivement, dans l’esprit postmoderne qui suppose que l’œuvre s’édifie sans plan préétabli, sur ses propres avancées.

Ce travail vise à apporter des éléments de réponse à plusieurs questions: quelles sont les relations entre ressources naturelles et conflits ?Quelle est la géographie des conflits liés à l’exploitation des ressources naturelles ?Quelle est l’origine des conflits liés à l’exploitation des ressources naturelles ?Après un bref aperçu critique des modèles développés dans la littérature contemporaine pour expliquer les relations entre conflits et ressources naturelles, le constat de leur insuffisance entraîne un examen approfondi de ces relations sous plusieurs angles. Il s’ensuit que les conflits liés aux ressources naturelles sont ceux qui ont trait à la répartition des ressources, aux conditions d’exploitation et à la répartition des revenus de l’exploitation des ressources. <p><p>À partir d’une classification des conflits selon une typologie des Etats du monde d’inspiration Centre-périphérie, l’argument principal de ce travail consiste à expliquer les conflits liés aux ressources naturelles – et plus largement tous les conflits – par l’amplification de deux phénomènes :le déclin de l’activité économique et l’exacerbation des tensions politiques. L’examen d’une série de cas (Aceh, Colombie, Angola, Afghanistan, Sierra Leone, Liberia, Cambodge) confirme la lecture matérialiste politico-économique des conflits liés à l’exploitation des ressources naturelles. Le rôle des structures d’appropriation du pouvoir et des revenus, en particulier de la rente des revenus issus de l’exploitation des ressources naturelles – cruciale dans des économies peu industrialisées – apparaît à la lumière du jour. <p><p>Enfin, ce travail offre quelques réflexions sur l’influence des structures d’appropriation dans l’éclatement et la durée des conflits. La question de l’origine des structures d’appropriation et de ses liens présumés avec la diffusion de la propriété privée en parallèle avec le développement du système-monde est ainsi développée, précédant la critique du rôle pseudo-développementaliste des ressources naturelles, dont le résultat de l’exploitation est surdéterminé par les structures d’appropriation locales (Tchad). Le travail se conclut sur une mise en perspective des enjeux du contrôle des territoires où sont exploités des ressources naturelles et de l’apport de cette question dans l’élaboration d’une géographie de la violence.<p> / Doctorat en sciences, Spécialisation géographie / info:eu-repo/semantics/nonPublished

Master of Science / Department of Statistics / Leigh Murray / The southern root-knot nematode (SRKN) and the weedy perennials, yellow nutsedge (YNS) and purple nutsedge (PNS) are simultaneously occurring pests in the irrigated agricultural soils of southern New Mexico. Previous research has very well characterized SRKN, YNS and PNS as a mutually-beneficial pest complex and has revealed their enhanced population growth and survival when they occur together. The density of nutsedge in a field could be used as a predictor of SRKN juveniles in the soil. In addition to SRKN, which is the most harmful of the plant parasitic nematodes, in southern New Mexico, other species or categories of nematodes could be identified and counted. Some of them are not as damaging to the plant as SRKN, and some of them may be essential for soil health. The nematode species could be grouped into categories according to trophic level (what nematodes eat) and herbivore feeding behavior (how herbivore nematodes eat). Subsequently, three ratios of counts were calculated for trophic level and for feeding behavior level to investigate the soil nematode community structure. These proportions were modeled as functions of the weed hosts YNS and PNS by generalized linear regression models using the logit link function and three probability distributions: the Binomial, Zero Inflated Binomial (ZIB) and Binomial Hurdle (BH). The latter two were used to account for potential high proportions of zeros in the data. The SAS NLMIXED procedure was used to fit models for each of the six sampling dates (May, July and September) over the two years of the alfalfa study. General results showed that the Binomial pmf generally provided the best fit, indicating lower zero-inflation than expected. Importance of YNS and PNS predictors varied over time and the different ratios. Specific results illustrate the differences in estimated probabilities between Binomial, ZIB and BH distributions as YNS counts increase for two selected ratios.

Made available in DSpace on 2014-06-11T19:30:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-10-05Bitstream added on 2014-06-13T18:40:59Z : No. of bitstreams: 1 moretti_jf_dr_ilha.pdf: 2346139 bytes, checksum: 4b4bfcffd24744e4627ebd26e46f3196 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O concreto é o material estrutural mais utilizado na construção civil. Há mais de um século e meio ele vem sendo estudado e aperfeiçoado. É confeccionado utilizando-se de matérias primas regionais, com características técnicas diferentes de outras regiões. O cimento também se apresenta com diversas formulações. Quantificar adequadamente esses materiais é o objetivo do estudo da dosagem do concreto, de tal modo a se obter um concreto que atenda às necessidades estruturais exigidas. Sendo a principal delas a resistência à compressão. A dosagem do concreto é uma prática essencialmente laboratorial quando se pensa em resultados aceitáveis. Através de experimentos são idealizados ábacos e diagramas que podem fornecer a resistência do concreto endurecido com diversas combinações de matérias primas utilizadas. Não há uma formulação matemática abrangente e bem definida para um processo generalizado de dosagem. A complexidade aumenta quando se adicionam outros componentes a mais no concreto simples e tradicional. Obter a relação entre eles é um trabalho contínuo. As redes neurais vêm sendo utilizadas na solução de problemas da engenharia civil, com ênfase na aplicação da técnica da retropropagação. Ela realiza satisfatoriamente as iterações entre as diversas variáveis, num processo de treinamento e aprendizagem, e tem sido capaz de generalizar soluções aceitáveis. Nesta pesquisa de doutorado é utilizada uma rede neural feedfoward com algoritmo retropropagação para prever a resistência e o módulo de elasticidade do concreto. Os dados de entrada são quantidades de materiais utilizadas para confeccionar 1 m3 de concreto adensado, de forma semelhante a dosagem por diagramas. Será aplicada na interpretação de diagramas de dosagem. Tais diagramas são amplamente utilizados por empresas na confecção de concretos,... / Concrete is the most widely used structural material in construction, for more than a century and a half it has been studied and improved. It's prepared using regional raw materials with different technical characteristics of other regions. The cement also performs with various formulations. Adequately quantify these materials is the goal of the study of the concrete mixtures proportion, to obtain a concrete that meets the structural needs required. The main one being the compressive strength. The strength of concrete is essentially a practice laboratory when one considers acceptable results. Through experiments are idealized abacus and diagrams that can provide the strength of hardened concrete with various combinations of raw materials used. There is no mathematical formulation of comprehensive and well defined for a generalized process of mixes. The complexity increases when other components is added in the most simple and traditional concrete. Obtain the relationship between them is a work in progress. Neural networks have been used in solving engineering problems, with emphasis on applying the technique of backpropagation. It performs satisfactorily iterations between the different variables in a process of training and learning, and has been able to generalize acceptable solutions. In this work is used a feedforward neural network with backpropagation algorithm to predict the compressive strength and modulus of elasticity of the concrete. The input data are quantities of materials used to fabricate 1,0 m3 of concrete hardened, similar dosing for diagrams and abacus. Such diagrams are widely used by companies in the manufacturing of concrete, yielding good precision in the final results. They are produced on the vast experience with the same materials and are highly regional representative to provide subsidies for training neural networks. This... (Complete abstract click electronic access below)

The aim of the diploma theses is to find out if the study in a form of an e-learning course is more beneficial to the student than the isolated study text. To find the benefits, the research among nineth grade students from two different schools was done. A study text called Functions for the nineth grade was prepared together with a collection of solved and unsolved problems. Based on this text an e-learning course called Functions for the nineth grade was prepared. The e-learning course was placed on the website linked http://funkcepro9r.maweb.eu/. For the communication of the students and the tutor of the course, for the completion of the compulsory tasks and for the carrying out the study agenda, the modul iTřída on the web link itrida.dumy.cz was selected. Both forms of the study materials were tested by the nineth grade students on two selected schools. The efectivity of both of the forms was tested by the written test. The evaluation of the both forms was done by the electronic questionnaire. According to the results of the written test, the students which used the isolated study text were more succesful than the students studying the e-learning course. The results of the questionnaire verified that the study text was more acceptable for the students. The e-learning course did not suit the...