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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.
41

Mineração de regras de associação em dados georreferenciados / Mining of association rules in geographic data

Marina Abichabki Pivato 21 March 2006 (has links)
Sistemas de informações geográficas permitem armazenar, manipular e armazenar, manipular e analisar dados espaciais e aspectos descritivos desses dados. A análise de dados espaciais pode ser realizada por meio de técnicas de extração de regras de associação, ou seja, regras que descrevem relacionamentos entre os dados. Porém, a mineração de regras de associação não considera as relações topológicas existentes entre dados georreferenciados. Para solucionar esse problema, Koperski and Han (1995) e Malerba et al. (2001) propuseram um processo de extração de regras integrado ao algoritmo de mineração e utilizavam predicados lógicos para representar as regras. Como alternativa a essa solução, este trabalho propõe pré-processar os dados referenciados para encontrar relações topológicas em separado e aplicar um algoritmo de mineração de regras de associação disponí?vel pela comunidade acadêmica. As regras geradas devem apresentar características descritivas dos dados e relações topológicas. Para atingir esse objetivo foi especificado um processo de extração de regras em dados georreferenciados e implementado um módulo de pré-processamento que extrai relações topológicas. O módulo foi avaliado por meio de um estudo de caso utilizando o sistema de informação geográfica da cidade de Jaboticabal, no contexto de planejamento urbano. As regras encontradas foram analisadas por um especialista utilizando as medidas de suporte e confiança. Além disso, uma análise sobre o tempo de processamento e consumo de memória para encontrar as relações topológicas foi realizada, mostrando que é possível extrair padrões utilizando o processo e o módulo proposto neste trabalho. / Geographic information systems are used to store, manipulate, and analyze spatial data and its descriptive aspects. Spatial data analysis can be done by searching association rules that describe relationships between the data. However, georeferenced data present topological relations unknown to traditional mining association rule algorithms. To solve this problem, Koperski and Han (1995) and Malerba et al. (2001) proposed a topological relation extraction process integrated to a mining association rule algorithm. This process requires all data to be translated as logical predicates. As an alternative to this solution, this work proposes to break down this process by pre-processing the georeferenced data to find topological relations, then executing traditional mining association rule algorithms. The resulting rules must present descriptive characteristics of the data and topological relations. To reach this objective, a process of rule extraction in georeferenced data was specified, in addition to a pre-processing module implementation. This module was evaluated by using a case study that uses a geographic information system of the city of Jaboticabal, in the context of urban planning. The generated rules were analyzed by a specialist using the measures of support and confidence. In addition, an analysis regarding the processing time and memory consumption was provided to find the topological relations, which shows that it is possible to extract the patterns with the proposed process and module.
42

Aplicando algoritmos de mineração de regras de associação para recuperação de informações multilíngues. / Cross-language information retrieval using algorithms for mining association rules

Geraldo, André Pinto January 2009 (has links)
Este trabalho propõe a utilização de algoritmos de mineração de regras de associação para a Recuperação de Informações Multilíngues. Esses algoritmos têm sido amplamente utilizados para analisar transações de registro de vendas. A ideia é mapear o problema de encontrar associações entre itens vendidos para o problema de encontrar termos equivalentes entre idiomas diferentes em um corpus paralelo. A proposta foi validada por meio de experimentos com diferentes idiomas, conjuntos de consultas e corpora. Os resultados mostram que a eficácia da abordagem proposta é comparável ao estado da arte, ao resultado monolíngue e à tradução automática de consultas, embora este utilize técnicas mais complexas de processamento de linguagem natural. Foi criado um protótipo que faz consultas à Web utilizando o método proposto. O sistema recebe palavras-chave em português, as traduz para o inglês e submete a consulta a diversos sites de busca. / This work proposes the use of algorithms for mining association rules as an approach for Cross-Language Information Retrieval. These algorithms have been widely used to analyze market basket data. The idea is to map the problem of finding associations between sales items to the problem of finding term translations over a parallel corpus. The proposal was validated by means of experiments using different languages, queries and corpora. The results show that the performance of our proposed approach is comparable to the performance of the monolingual baseline and to query translation via machine translation, even though these systems employ more complex Natural Language Processing techniques. A prototype for cross-language web querying was implemented to test the proposed method. The system accepts keywords in Portuguese, translates them into English and submits the query to several web-sites that provide search functionalities.
43

Construção semi-automática de taxonomias para generalização de regras de associação / Semi-automatic construction of taxonomies for association rules generation

Camila Delefrate Martins 14 July 2006 (has links)
Para o sucesso do processo de mineração de dados é importante que o conhecimento extraí?do seja compreensível e interessante para que o usuário final possa utilizá-lo em um sistema inteligente ou em processos de tomada de decisão. Um grande problema, porém, é identificado quando a tarefa de mineração de dados denominada associação é utilizada: a geração de um grande volume de regras. Taxonomias podem ser utilizadas para facilitar a análise e interpretação das regras de associação, uma vez que as mesmas provêm uma visão de como os itens podem ser hierarquicamente classificados. Em função dessa hierarquia é possível obter regras mais gerais que representem um conjunto de itens. Dentro desse contexto, neste trabalho é apresentada uma metodologia para construção semi-automática de taxonomias, que inclui procedimentos automáticos e interativos para a realização dessa tarefa. Essa combinação possibilita a utilização do conhecimento do especialista e também o auxilia na identificação de grupos. Entre os principais resultados deste trabalho, pode-se destacar a proposta e implementação do algoritmo SACT (Semi-automatic Construction of Taxonomies - Construção Semi-automática de Taxonomias), que provê a utilização da metodologia proposta. Para viabilizar a utilização do algoritmo, foi desenvolvido o módulo computacional RulEESACT. Com o objetivo de viabilizar e analisar a qualidade da metodologia proposta e do módulo desenvolvido, foi realizado um estudo de caso no qual foram construída taxonomias para duas bases de dados utilizando o RulEE-SACT. Uma das taxonomias foi analisada e validada por uma especialista do domínio. Posteriormente, as taxonomias e as bases de transações foram fornecidas para dois algoritmos de generalização de regras de associação a fim de analisar a aplicação das taxonomias geradas / I n the data mining process it is important that the extracted knowledge is understandable and interesting to the final user, so it can be used to support in the decision making. However, the data mining task named association has one problem: it generates a big volume of rules. Taxonomies can be used to facilitate the analysis and interpretation of association rules, because they provide an hierarchical vision of the items. This hierarchy enables the obtainment of more general rules, which represent a set of items. In this context, a methodology to semi-automatically construct taxonomies is proposed in this work. This methodology includes automatic and interactives procedures in order to construct the taxonomies, using the specialist?s knowledge and also assisting in the identification of groups. One of the main results of this work is the proposal and implementation of the SACT (Semi-automatic Construction of Taxonomies) algorithm, which provides the use of the proposed methodology. In order to facilitate the use of this algorithm, a computational module named RulEE-SACT was developed. Aiming to analyze the viability and quality of the proposed methodology and the developed module, a case study was done. In this case study, taxonomies of two databases were constructed using the RulEE-SACT. One of them was analyzed and validated by a domain specialist. Then the taxonomies and the databases were supplied to two algorithms which generalize association rules, aiming to analyze the use of the generated taxonomies
44

Data mining em banco de dados de eletrocardiograma / Data mining in electrocardiogram databases

José Alves Ferreira 23 April 2014 (has links)
Neste estudo, foi proposta a exploração de um banco de dados, com informações de exames de eletrocardiogramas (ECG), utilizado pelo sistema denominado Tele-ECG do Instituto Dante Pazzanese de Cardiologia, aplicando a técnica de data mining (mineração de dados) para encontrar padrões que colaborem, no futuro, para a aquisição de conhecimento na análise de eletrocardiograma. A metodologia proposta permite que, com a utilização de data mining, investiguem-se dados à procura de padrões sem a utilização do traçado do ECG. Três pacotes de software (Weka, Orange e R-Project) do tipo open source foram utilizados, contendo, cada um deles, um conjunto de implementações algorítmicas e de diversas técnicas de data mining, além de serem softwares de domínio público. Regras conhecidas foram encontradas (confirmadas pelo especialista médico em análise de eletrocardiograma), evidenciando a validade dessa metodologia. / In this study, the exploration of electrocardiograms (ECG) databases, obtained from a Tele-ECG System of Dante Pazzanese Institute of Cardiology, has been proposed, applying the technique of data mining to find patterns that could collaborate, in the future, for the acquisition of knowledge in the analysis of electrocardiograms. The proposed method was to investigate the data looking for patterns without the use of the ECG traces. Three Data-mining open source software packages (Weka, Orange and R - Project) were used, containing, each one, a set of algorithmic implementations and various data mining techniques, as well as being a public domain software. Known rules were found (confirmed by medical experts in electrocardiogram analysis), showing the validity of the methodology.
45

Association Rules in Parameter Tuning : for Experimental Designs

Hållén, Henrik January 2014 (has links)
The objective of this thesis was to investigate the possibility ofusing association rule algorithms to automatically generaterules for the output of a Parameter Tuning framework. Therules would be the basis for a recommendation to the user regardingwhich parameter space to reduce during experimentation.The parameter tuning output was generated by means ofan open source project (INPUT) example program. InPUT is atool used to describe computer experiment configurations in aframework independent input/output format. InPUT has adaptersfor the evolutionary algorithm framework Watchmakerand the tuning framework SPOT. The output was imported in Rand preprocessed to a format suitable for association rule algorithms.Experiments were conducted on data for which theparameter spaces were discretized in 2, 5, 10 steps. The minimumsupport threshold was set to 1% and 3% to investigatethe amount of rules over time. The Apriori and Eclat algorithmsproduced exactly the same amount of rules, and the top 5rules with regards to support were basically the same for bothalgorithms. It was not possible at the time to automatically distinguishinguseful rules. In combination with the many manualdecisions during the process of converting the tuning output toassociation rules, the conclusion was reached to not recommendassociation rules for enhancing the Parameter Tuningprocess.
46

Pruning and summarizing discovered time series association rules

Qing, Yang January 2017 (has links)
Sensors are widely used in all aspects of our daily life including factories, hospitals and even our homes. Discovering time series association rules from sensor data can reveal the potential relationship between different sensors which can be used in many applications. However, the time series association rule mining algorithms usually produce rules much more than expected. It’s hardly to under-stand, present or make use of the rules. So we need to prune and summarize the huge amount of rules. In this paper, a two-step pruning method is proposed to reduce both the number and redundancy in the large set of time series rules. Be-sides, we put forward the BIGBAR summarizing method to summarize the rules and present the results intuitively.
47

Discovery of temporal association rules in multivariate time series

Zhao, Yi January 2017 (has links)
This thesis focuses on mining association rules on multivariate time series. Com-mon association rule mining algorithms can usually only be applied to transactional data, and a typical application is market basket analysis. If we want to mine temporal association rules on time series data, changes need to be made. During temporal association rule mining, the temporal ordering nature of data and the temporal interval between the left and right patterns of a rule need to be considered. This thesis reviews some mining methods for temporal association rule mining, and proposes two similar algorithms for the mining of frequent patterns in single and multivariate time series. Both algorithms are scalable and efficient. In addition, temporal association rules are generated from the patterns found. Finally, the usability and efficiency of the algorithms are demonstrated by evaluating the results.
48

Vytváření webové analytické zprávy z metabáze systému LISp-Miner / Creation of web-based analytics report from LISp-Miner metabase analytics

Nepomucký, Pavel January 2017 (has links)
This diploma thesis deals with ways how to represent results of LISp-Miner application on the world wide web. This thesis has three main sections. The first section is dedicated to description of data analysis process including description of newly established study of infography and its application in publishing results found du-ring the DZD process. The second part describes exporting of LISp-Miner as well as exporting formats of each module and its combining with other technologies, afterwards follows summarization of all kind of exports of lispminer and its im-provements or create a whole new templates. Third part is dedicated to develop-ment of a web-based application as a tool of repsentation results generated by lispminer. The very last part is contained of future improvements of this application.
49

Analýza reálných dat produktové redakce Alza.cz pomocí metod DZD / Analysis of real data from Alza.cz product department using methods of KDD

Válek, Martin January 2014 (has links)
This thesis deals with data analysis using methods of knowledge discovery in databases. The goal is to select appropriate methods and tools for implementation of a specific project based on real data from Alza.cz product department. Data analysis is performed by using association rules and decision rules in the Lisp-Miner and decision trees in the RapidMiner. The methodology used is the CRISP-DM. The thesis is divided into three main sections. First section is focused on the theoretical summary of information about KDD. There are defined basic terms and described the types of tasks and methods of KDD. In the second section is introduced the methodology CRISP-DM. The practical part firstly introduces company Alza.cz and its goals for this task. Afterwards, the basic structure of the data and preparation for the next step (data mining) is described. In conclusion, the results are evaluated and the possibility of their use is outlined.
50

Identificação de regras de associação interessantes por meio de análises com medidas objetivas e subjetivas / Identification of interesting association rules through objective and subjective measures analysis

Roberta Akemi Sinoara 30 March 2006 (has links)
A associação é uma tarefa de mineração de dados que tem sido muito utilizada em problemas reais, porém o grande número de regras de associação que podem ser geradas dificulta a identificação de conhecimento interessante aos usuários. Para apoiar a identificação de regras interessantes podem ser utilizadas medidas de avaliação de conhecimento, que normalmente são classificadas como objetivas ou subjetivas. As medidas objetivas são mais gerais, mas podem não ser suficientes por não considerarem aspectos relacionados ao usuário ou ao domínio da aplicação. Por outro lado pode haver dificuldade em se obter a subjetividade do usuário necessária para o cálculo das medidas subjetivas. Diante desse contexto, neste trabalho é proposta uma metodologia para identificação de regras de associação interessantes que combina análises com medidas objetivas e subjetivas, visando aproveitar as vantagens de cada tipo e facilitar a participação do especialista. As medidas objetivas são utilizadas para selecionar algumas regras potencialmente interessantes para serem avaliadas por um especialista. As medidas subjetivas são calculadas utilizando essas regras com as avaliações do especialista. Essas medidas subjetivas então são utilizadas para auxiliar a identificação de regras interessantes de acordo com o conhecimento obtido durante a avaliação. Para viabilizar a aplicação dessa metodologia foi desenvolvido um módulo computacional de exploração de regras de associação com medidas subjetivas, denominado RulEE-SEAR. Utilizando esse módulo e outras ferramentas já existentes foi realizado um estudo de caso com uma base de dados real sobre qualidade de vida urbana. Nesse estudo de caso o processo de identificação de regras de associação interessantes foi realizado com especialista da área e verificou-se a viabilidade da metodologia proposta. / Association is a data mining task which has been applied in several real problems. However, due to the huge number of association rules that can be generated, it is hard for users to identify interesting knowledge. To assist users in finding interesting rules, evaluation measures can be used. Those measures are usually divided into objective and subjective. Objective measures are more general, but they can be insufficient because they do not consider user's and domain's features. On the other hand, getting users's knowledge and interest needed to calculate subjective measures can be a difficult task. In this context, a methodology to identify interesting association rules is proposed in this work. This methodology combines analysis with objective and subjective measures, aiming to use the advantages of each kind of measure and to make user's participation easier. Objective measures are used to select some potentially interesting rules for the user's evaluation. These rules and the evaluation are used to calculate subjective measures. Then, the subjective measures are used to assist the user in identifying interesting rules according to the knowledge obtained during the evaluation. To make the methodology use practicable, a computational module, named RulEE-SEAR, was developed to explore the association rules with subjective measures. Using this module and other existing tools, a case study was done. A urban life quality database was used and a specialist in this area participated in the interesting association rules identification. That case study showed that the methodology proposed is feasible.

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