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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

Análise de dados sequenciais heterogêneos baseada em árvore de decisão e modelos de Markov : aplicação na logística de transporte

Ataky, Steve Tsham Mpinda 16 October 2015 (has links)
Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-16T12:52:39Z No. of bitstreams: 1 DissSATM.pdf: 3079104 bytes, checksum: 51b46ffeb4387370e30fb92e31771606 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:59:28Z (GMT) No. of bitstreams: 1 DissSATM.pdf: 3079104 bytes, checksum: 51b46ffeb4387370e30fb92e31771606 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:59:34Z (GMT) No. of bitstreams: 1 DissSATM.pdf: 3079104 bytes, checksum: 51b46ffeb4387370e30fb92e31771606 (MD5) / Made available in DSpace on 2016-09-16T19:59:41Z (GMT). No. of bitstreams: 1 DissSATM.pdf: 3079104 bytes, checksum: 51b46ffeb4387370e30fb92e31771606 (MD5) Previous issue date: 2015-10-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Latterly, the development of data mining techniques has emerged in many applications’ fields with aim at analyzing large volumes of data which may be simple and / or complex. The logistics of transport, the railway setor in particular, is a sector with such a characteristic in that the data available in are of varied natures (classic variables such as top speed or type of train, symbolic variables such as the set of routes traveled by train, degree of tack, etc.). As part of this dissertation, one addresses the problem of classification and prediction of heterogeneous data; it is proposed to study through two main approaches. First, an automatic classification approach was implemented based on classification tree technique, which also allows new data to be efficiently integrated into partitions initialized beforehand. The second contribution of this work concerns the analysis of sequence data. It has been proposed to combine the above classification method with Markov models for obtaining a time series (temporal sequences) partition in homogeneous and significant groups based on probabilities. The resulting model offers good interpretation of classes built and allows us to estimate the evolution of the sequences of a particular vehicle. Both approaches were then applied onto real data from the a Brazilian railway information system company in the spirit of supporting the strategic management of planning and coherent prediction. This work is to initially provide a thinner type of planning to solve the problems associated with the existing classification in homogeneous circulations groups. Second, it sought to define a typology of train paths (sucession traffic of the same train) in order to provide or predict the next movement of statistical characteristics of a train carrying the same route. The general methodology provides a supportive environment for decision-making to monitor and control the planning organization. Thereby, a formula with two variants was proposed to calculate the adhesion degree between the track effectively carried out or being carried out with the planned one. / Nos últimos anos aflorou o desenvolvimento de técnicas de mineração de dados em muitos domínios de aplicação com finalidade de analisar grandes volumes de dados, os quais podendo ser simples e/ou complexos. A logística de transporte, o setor ferroviário em particular, é uma área com tal característica em que os dados disponíveis são muitos e de variadas naturezas (variáveis clássicas como velocidade máxima ou tipo de trem, variáveis simbólicas como o conjunto de vias percorridas pelo trem, etc). Como parte desta dissertação, aborda-se o problema de classificação e previsão de dados heterogêneos, propõe-se estudar através de duas abordagens principais. Primeiramente, foi utilizada uma abordagem de classificação automática com base na técnica por ´arvore de classificação, a qual também permite que novos dados sejam eficientemente integradas nas partições inicial. A segunda contribuição deste trabalho diz respeito à análise de dados sequenciais. Propôs-se a combinar o método de classificação anterior com modelos de Markov para obter uma participação de sequências temporais em grupos homogêneos e significativos com base nas probabilidades. O modelo resultante oferece uma boa interpretação das classes construídas e permite estimar a evolução das sequências de um determinado veículo. Ambas as abordagens foram então aplicadas nos dados do sistema de informação ferroviário, no espírito de dar apoio à gestão estratégica de planejamentos e previsões aderentes. Este trabalho consiste em fornecer inicialmente uma tipologia mais fina de planejamento para resolver os problemas associados com a classificação existente em grupos de circulações homogêneos. Em segundo lugar, buscou-se definir uma tipologia de trajetórias de trens (sucessão de circulações de um mesmo trem) para assim fornecer ou prever características estatísticas da próxima circulação mais provável de um trem realizando o mesmo percurso. A metodologia geral proporciona um ambiente de apoio à decisão para o monitoramento e controle da organização de planejamento. Deste fato, uma fórmula com duas variantes foi proposta para calcular o grau de aderência entre a trajetória efetivamente realizada ou em curso de realização com o planejado.
32

Decision Support Systems for Financial Market Surveillance

Alic, Irina 30 November 2016 (has links)
Entscheidungsunterstützungssysteme in der Finanzwirtschaft sind nicht nur für die Wis-senschaft, sondern auch für die Praxis von großem Interesse. Um die Finanzmarktüber-wachung zu gewährleisten, sehen sich die Finanzaufsichtsbehörden auf der einen Seite, mit der steigenden Anzahl von onlineverfügbaren Informationen, wie z.B. den Finanz-Blogs und -Nachrichten konfrontiert. Auf der anderen Seite stellen schnell aufkommen-de Trends, wie z.B. die stetig wachsende Menge an online verfügbaren Daten sowie die Entwicklung von Data-Mining-Methoden, Herausforderungen für die Wissenschaft dar. Entscheidungsunterstützungssysteme in der Finanzwirtschaft bieten die Möglichkeit rechtzeitig relevante Informationen für Finanzaufsichtsbehörden und Compliance-Beauftragte von Finanzinstituten zur Verfügung zu stellen. In dieser Arbeit werden IT-Artefakte vorgestellt, welche die Entscheidungsfindung der Finanzmarktüberwachung unterstützen. Darüber hinaus wird eine erklärende Designtheorie vorgestellt, welche die Anforderungen der Regulierungsbehörden und der Compliance-Beauftragten in Finan-zinstituten aufgreift.
33

Intelligent flood adaptative contex-aware system / Système sensible et adaptatif au contexte pour la gestion intelligente de crues

Sun, Jie 23 October 2017 (has links)
A l’avenir, l'agriculture et l'environnement vont pouvoir bénéficier de plus en plus de données hétérogènes collectées par des réseaux de capteurs sans fil (RCSF). Ces données alimentent généralement des outils d’aide à la décision (OAD). Dans cette thèse, nous nous intéressons spécifiquement aux systèmes sensibles et adaptatifs au contexte basés sur un RCSF et un OAD, dédiés au suivi de phénomènes naturels. Nous proposons ainsi une formalisation pour la conception et la mise en œuvre de ces systèmes. Le contexte considéré se compose de données issues du phénomène étudié mais également des capteurs sans fil (leur niveau d’énergie par exemple). Par l’utilisation des ontologies et de techniques de raisonnement, nous visons à maintenir le niveau de qualité de service (QdS) des données collectées (en accord avec le phénomène étudié) tant en préservant le fonctionnement du RCSF. Pour illustrer notre proposition, un cas d'utilisation complexe, l'étude des inondations dans un bassin hydrographique, est considéré. Cette thèse a produit un logiciel de simulation de ces systèmes qui intègre un système de simulation multi-agents (JADE) avec un moteur d’inférence à base de règles (Jess). / In the future, agriculture and environment will rely on more and more heterogeneous data collected by wireless sensor networks (WSN). These data are generally used in decision support systems (DSS). In this dissertation, we focus on adaptive context-aware systems based on WSN and DSS, dedicated to the monitoring of natural phenomena. Thus, a formalization for the design and the deployment of these kinds of systems is proposed. The considered context is established using the data from the studied phenomenon but also from the wireless sensors (e.g., their energy level). By the use of ontologies and reasoning techniques, we aim to maintain the required quality of service (QoS) level of the collected data (according to the studied phenomenon) while preserving the resources of the WSN. To illustrate our proposal, a complex use case, the study of floods in a watershed, is described. During this PhD thesis, a simulator for context-aware systems which integrates a multi-agent system (JADE) and a rule engine (Jess) has been developed.Keywords: ontologies, rule-based inferences, formalization, heterogeneous data, sensors data streams integration, WSN, limited resources, DSS, adaptive context-aware systems, QoS, agriculture, environment.

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