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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.
51

土地資訊系統中含時間維度之資料管理

陳怡茹, Che,I-ju Unknown Date (has links)
隨著地籍管理工作在廣度深度上的增加,使得地籍、土地利用等歷史資料的查詢與檢索日益頻繁,但現階段地籍管理系統之建置方法對於歷史資料查詢之效率較差。本文在探討含時間維度資料庫之建置方法,並利用異動時間與異動註記等欄位及異動紀錄表之建立,令目前地籍管理系統可達到以時間維度,或指定地號,進行地籍資料查詢與檢索。 / The more cadastral management is developed, the more historic data query of cadastre and land use are important. The primary purpose of this study is concentrated on the recoveries of parcel linage and areas on any time profile. The targets of this research are placed on design of spatio-temporal data model, and the analysis of efficiency of data recovery and query.
52

Monitoring gene level biodiversity - aspects and considerations in the context of conservation

Charlier, Johan January 2011 (has links)
The objectives of this thesis relate to questions needed to be addressed in the context of genetic monitoring for implementing the Convention on Biological Diversity for the gene level. Genetic monitoring is quantifying temporal changes in population genetic metrics. Specific goals of this thesis include i) synthesizing existing information relevant to genetic monitoring of Swedish species, ii) providing a genetic baseline for the Swedish moose, iii) evaluating the relative performance of nuclear versus organelle genetic markers for detecting population divergence, iv) actually monitoring the genetic composition, structure, level of variation, and effective population size (Ne) and assessing the relation between Ne and the actual number of individuals for an unexploited brown trout population. The concept of conservation genetic monitoring is defined and Swedish priority species for such monitoring are identified; they include highly exploited organisms such as moose, salmonid fishes, Norway spruce, Atlantic cod, and Atlantic herring. Results indicate that the Swedish moose might be more genetically divergent than previously anticipated and appears to be divided into at least three different subpopulations, representing a southern, a central, and a northern population. The relative efficiency of nuclear and organelle markers depends on the relationship between the degree of genetic differentiation at the two types of markers. In turn, this relates to how far the divergence process has progressed. For the monitored brown trout population no indication of systematic change of population structure or allele frequencies was observed over 30 years. Significant genetic drift was found, though, translating into an overall Ne-estimate of ~75. The actual number of adult fish (NC) was assessed as ~600, corresponding to an Ne/NC ratio of 0.13. In spite of the relatively small effective population size monitoring did not reveal loss of genetic variation.
53

Analisando padrões de mobilidade a partir de redes sociais e de dados sócio demográficos abertos.

JERÔNIMO, Caio Libânio Melo. 30 August 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-08-30T17:25:22Z No. of bitstreams: 1 CAIO LIBÂNIO MELO JERÔNIMO – DISSERTAÇÃO (PPGCC) 2017.pdf: 4821943 bytes, checksum: 615dc29730ed480c902a5496dce5492f (MD5) / Made available in DSpace on 2018-08-30T17:25:22Z (GMT). No. of bitstreams: 1 CAIO LIBÂNIO MELO JERÔNIMO – DISSERTAÇÃO (PPGCC) 2017.pdf: 4821943 bytes, checksum: 615dc29730ed480c902a5496dce5492f (MD5) Previous issue date: 2017-07-07 / Capes / A demanda constante por melhorias na qualidade de vida dos habitantes das grandes cidades, somado à crescente urbanização desses centros, torna imprescindível a utilização de meios tecnológicos para um melhor entendimento da dinâmica dos centros urbanos e como seus habitantes interagem nesses ambientes. Nesse sentido, o aumento na utilização de dispositivos eletrônicos equipados com sistemas GPS e o constante anseio da humanidade por comunicação e, mais atualmente, por conexão à internet, vem criando novas oportunidades de estudo e também grandes desafios, especialmente no que tange a grande quantidade de dados gerados pelas redes sociais. Diversas pesquisas vêm utilizando esses dados para realizar estudos que buscam compreender traços do comportamento humano, especialmente no que diz respeito à mobilidade urbana e trajetórias. Porém, grande parte das pesquisas que utilizam dados georreferenciados se restringem às dimensões espaciais e temporais, desconsiderando outros aspectos que podem influenciar na mobilidade humana. Este trabalho propõe um método computacional capaz de extrair padrões de mobilidade oriundos de mensagens georreferenciadas de redes sociais e correlacioná-los com indicadores sociais, econômicos e demográficos fornecidos por órgãos governamentais, buscando assim, analisar quais possíveis fatores poderiam exercer alguma influência sobre a mobilidade dos moradores de uma grande cidade. Para validar o método proposto, foram utilizadas mensagens postadas no Twitter e um conjunto de indicadores sociais, ambos oriundos da cidade de Londres. Os resultados mostraram a existência de correlações entre padrões de mobilidade e indicadores sociais, especialmente os relacionados com condições de emprego e renda, como também com características étnico-religiosas dos indivíduos em estudo. / The constant need for improvements in life quality of inhabitants of big cities, together with the increasing urbanization of these centers, demands the use of technological means for a better understanding of the dynamics of urban centers and how their inhabitants interact in these environments. In this sense, the adoption of electronic devices equipped with GPS systems, the human need for communication and, more recently, for Internet connection, have brought new research opportunities and great challenges, especially due to the huge amount of data generated by social networks. Several studies have used this data to carry out research that seek to understand traces of human behavior, especially with respect to urban mobility and trajectories. However, much of the research that uses georeferenced data are restricted to spatial and temporal dimensions, disregarding other aspects that may influence human mobility. This work proposes a model capable of extracting mobility patterns from georeferenced messages of social networks and correlating them with social, economic and demographic indicators provided by government agencies, seeking to analyze which factors may impact in urban mobility. To evaluate the model, we used messages posted on Twitter and a set of social indicators, both related to the city of London. The results revealed the existence of correlations between mobility patterns and social indicators, especially those related to employment and income conditions, as well as ethnic and religious characteristics of the individuals under study.
54

Impacts of Climate Change on US Commercial and Residential Building Energy Demand

January 2016 (has links)
abstract: Energy consumption in buildings, accounting for 41% of 2010 primary energy consumption in the United States (US), is particularly vulnerable to climate change due to the direct relationship between space heating/cooling and temperature. Past studies have assessed the impact of climate change on long-term mean and/or peak energy demands. However, these studies usually neglected spatial variations in the “balance point” temperature, population distribution effects, air-conditioner (AC) saturation, and the extremes at smaller spatiotemporal scales, making the implications of local-scale vulnerability incomplete. Here I develop empirical relationships between building energy consumption and temperature to explore the impact of climate change on long-term mean and extremes of energy demand, and test the sensitivity of these impacts to various factors. I find increases in summertime electricity demand exceeding 50% and decreases in wintertime non-electric energy demand of more than 40% in some states by the end of the century. The occurrence of the most extreme (appearing once-per-56-years) electricity demand increases more than 2600 fold, while the occurrence of the once per year extreme events increases more than 70 fold by the end of this century. If the changes in population and AC saturation are also accounted for, the impact of climate change on building energy demand will be exacerbated. Using the individual building energy simulation approach, I also estimate the impact of climate change to different building types at over 900 US locations. Large increases in building energy consumption are found in the summer, especially during the daytime (e.g., >100% increase for warehouses, 5-6 pm). Large variation of impact is also found within climate zones, suggesting a potential bias when estimating climate-zone scale changes with a small number of representative locations. As a result of climate change, the building energy expenditures increase in some states (as much as $3 billion/year) while in others, costs decline (as much as $1.4 billion/year). Integrated across the contiguous US, these variations result in a net savings of roughly $4.7 billion/year. However, this must be weighed against the cost (exceeding $19 billion) of adding electricity generation capacity in order to maintain the electricity grid’s reliability in summer. / Dissertation/Thesis / Doctoral Dissertation Environmental Social Science 2016
55

Apprentissage de règles associatives temporelles pour les séquences temporelles de symboles / Learning temporal association rules on Symbolic time sequences

Guillame-Bert, Mathieu 23 November 2012 (has links)
L'apprentissage de modèles temporels constitue l'une des grandes problématiques de l'Exploration de Données (Data Mining). Dans cette thèse, nous avons développé un nouveau modèle temporel appelé TITA Rules (Règle associative temporelle basé sur des arbres d'intervalles). Ce modèle permet de décrire des phénomènes ayant un certain degré d'incertitude et/ou d'imprécision. Ce modèle permet entre autres d'exprimer la synchronicité entre évènements, les contraintes temporelles disjonctives et la négation temporelle. De par leur nature, les TITA Rules peuvent êtes utilisées pour effectuer des prédictions avec une grande précision temporel. Nous avons aussi développé un algorithme capable de découvrir et d'extraire de manière efficace des TITA Rules dans de grandes bases de données temporelles. Le cœur de l'algorithme est basé sur des techniques de minimisation d'entropie, de filtrage par Apriori et par des analyses de co-dépendance. Note modèle temporelle et notre algorithme ont été appliqués et évalués sur plusieurs jeux de données issues de phénomènes réels et de phénomènes simulés. La seconde partie de cette thèse à consisté à étudier l'utilisation de notre modèle temporel sur la problématique de la Planification Automatique. Ces travaux ont mené au développement d'un algorithme de planification automatique. L'algorithme prend en entrée un ensemble de TITA Rules décrivant le fonctionnement d'un système quelconque, une description de l'état initial du système, et un but à atteindre. En retour, l'algorithme calcule un plan décrivant la meilleure façon d'atteindre le but donné. Par la nature même des TITA Rules, cet algorithme est capable de gérer l'incertain (probabilités), l'imprécision temporelle, les contraintes temporelles disjonctives, ainsi que les événements exogènes prédictibles mais imprécis. / The learning of temporal patterns is a major challenge of Data mining. We introduce a temporal pattern model called Temporal Interval Tree Association Rules (Tita rules or Titar). This pattern model can be used to express both uncertainty and temporal inaccuracy of temporal events. Among other things, Tita rules can express the usual time point operators, synchronicity, order, and chaining,disjunctive time constraints, as well as temporal negation. Tita rules are designed to allow predictions with optimum temporal precision. Using this representation, we present the Titar learner algorithm that can be used to extract Tita rules from large datasets expressed as Symbolic Time Sequences. This algorithm based on entropy minimization, apriori pruning and statistical dependence analysis. We evaluate our technique on simulated and real world datasets. The problem of temporal planning with Tita rules is studied. We use Tita rules as world description models for a Planning and Scheduling task. We present an efficient temporal planning algorithm able to deal with uncertainty, temporal inaccuracy, discontinuous (or disjunctive) time constraints and predictable but imprecisely time located exogenous events. We evaluate our technique by joining a learning algorithm and our planning algorithm into a simple reactive cognitive architecture that we apply to control a robot in a virtual world.
56

STB-index : um índice baseado em bitmap para data warehouse espaço-temporal

Tsuruda, Renata Miwa 13 December 2012 (has links)
Made available in DSpace on 2016-06-02T19:06:04Z (GMT). No. of bitstreams: 1 5138.pdf: 2676227 bytes, checksum: 72ab4695bfe8833d7d34d1e803a6ec9a (MD5) Previous issue date: 2012-12-13 / Financiadora de Estudos e Projetos / The growing concern with the support of the decision-making process has made companies to search technologies that support their decisions. The technology most widely used presently is the Data Warehouse (DW), which allows storing data so it is possible to produce useful and reliable information to assist in strategic decisions. Combining the concepts of Spatial Data Warehouse (SDW), that allows geometry storage and managing, and Temporal Data Warehouse (TDW), which allows storing data changes that occur in the real-world, a research topic known as Spatio-Temporal Data Warehouse (STDW) has emerged. STDW are suitable for the treatment of geometries that change over time. These technologies, combined with the steady growth volume of data, show the necessity of index structures to improve the performance of analytical query processing with spatial predicates and also with geometries that may vary over time. In this sense, this work focused on proposing an index for STDW called Spatio-Temporal Bitmap Index, or STB-index. The proposed index was designed to processing drill-down and roll-up queries considering the existence of predefined spatial hierarchies and with spatial attributes that can vary its position and shape over time. The validation of STB-index was performed by conducting experimental tests using a DWET created from synthetic data. Tests evaluated the elapsed time and the number of disk accesses to construct the index, the amount of storage space of the index and the elapsed time and the number of disk accesses for query processing. Results were compared with query processing using database management system resources and STBindex improved the query performance by 98.12% up to 99.22% in response time compared to materialized views. / A crescente preocupação com o suporte ao processo de tomada de decisão estratégica fez com que as empresas buscassem tecnologias que apoiassem as suas decisões. A tecnologia mais utilizada atualmente é a de Data Warehouse (DW), que permite armazenar dados de forma que seja possível produzir informação útil e confiável para auxiliar na tomada de decisão estratégica. Aliando-se os conceitos de Data Warehouse Espacial (DWE), que permite o armazenamento e o gerenciamento de geometrias, e de Data Warehouse Temporal (DWT), que possibilita representar as mudanças nos dados que ocorrem no mundo real, surgiu o tema de pesquisa conhecido por Data Warehouse Espaço-Temporal (DWET), que é próprio para o tratamento de geometrias que se alteram ao longo do tempo. Essas tecnologias, aliadas ao constante crescimento no volume de dados armazenados, evidenciam a necessidade de estruturas de indexação que melhorem o desempenho do processamento de consultas analíticas com predicados espaciais e com variação das geometrias no tempo. Nesse sentido, este trabalho se concentrou na proposta de um índice para DWET denominado Spatio- Temporal Bitmap Index, ou STB-index. O índice proposto foi projetado para o processamento de consultas do tipo drill-down e roll-up considerando a existência de hierarquias espaciais predefinidas, sendo que os atributos espaciais podem variar sua posição e sua forma ao longo do tempo. A validação do STB-index ocorreu por meio da realização de testes experimentais utilizando um DWET criado a partir de dados sintéticos. Os testes avaliaram o tempo e o número de acessos a disco para a construção do índice, a quantidade de espaço para armazenamento do índice e o tempo e número de acessos a disco para o processamento de consultas analíticas. Os resultados obtidos foram comparados com o processamento de consultas utilizando os recursos disponíveis dos sistemas gerenciadores de banco de dados, sendo que o STB-index apresentou um ganho de desempenho entre 98,12% e 99,22% no tempo de resposta das consultas se comparado ao uso de visões materializadas.
57

Análise de desempenho de consultas OLAP espaçotemporais em função da ordem de processamento dos predicados convencional, espacial e temporal

Joaquim Neto, Cesar 08 March 2016 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-10-07T20:05:05Z No. of bitstreams: 1 DissCJN.pdf: 5948964 bytes, checksum: e7e719e26b50a85697e7934bde411070 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:30:58Z (GMT) No. of bitstreams: 1 DissCJN.pdf: 5948964 bytes, checksum: e7e719e26b50a85697e7934bde411070 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T19:31:04Z (GMT) No. of bitstreams: 1 DissCJN.pdf: 5948964 bytes, checksum: e7e719e26b50a85697e7934bde411070 (MD5) / Made available in DSpace on 2016-10-20T19:31:09Z (GMT). No. of bitstreams: 1 DissCJN.pdf: 5948964 bytes, checksum: e7e719e26b50a85697e7934bde411070 (MD5) Previous issue date: 2016-03-08 / Não recebi financiamento / By providing ever-growing processing capabilities, many database technologies have been becoming important support tools to enterprises and institutions. The need to include (and control) new data types to the existing database technologies has brought also new challenges and research areas, arising the spatial, temporal, and spatiotemporal databases. Besides that, new analytical capabilities were required facilitating the birth of the data warehouse technology and, once more, the need to include spatial or temporal data (or both) to it, thus originating the spatial, temporal, and spatio-temporal data warehouses. The queries used in each database type had also evolved, culminating in the STOLAP (Spatio Temporal OLAP) queries, which are composed of predicates dealing with conventional, spatial, and temporal data with the possibility of having their execution aided by specialized index structures. This work’s intention is to investigate how the execution of each predicate affects the performance of STOLAP queries by varying the used indexes, their execution order and the query’s selectivity. Bitmap Join Indexes will help in conventional predicate’s execution and in some portions of the temporal processing, which will also count with the use of SQL queries for some of the alternatives used in this research. The SB-index and HSB-index will aid the spatial processing while the STB-index will be used to process temporal and spatial predicates together. The expected result is an analysis of the best predicate order while running the queries also considering their selectivity. Another contribution of this work is the evolution of the HSB-index to a hierarchized version called HSTB-index, which should complement the execution options. / Por proverem uma capacidade de processamento de dados cada vez maior, várias tecnologias de bancos de dados têm se tornado importantes ferramentas de apoio a empresas e instituições. A necessidade de se incluir e controlar novos tipos de dados aos bancos de dados já existentes fizeram também surgir novos desafios e novas linhas de pesquisa, como é o caso dos bancos de dados espaciais, temporais e espaçotemporais. Além disso, novas capacidades analíticas foram se fazendo necessárias culminando com o surgimento dos data warehouses e, mais uma vez, com a necessidade de se incluir dados espaciais e temporais (ou ambos) surgindo os data warehouses espaciais, temporais e espaço-temporais. As consultas relacionadas a cada tipo de banco de dados também evoluíram culminando com as consultas STOLAP (Spatio-Temporal OLAP) que são compostas basicamente por predicados envolvendo dados convencionais, espaciais e temporais e cujo processamento pode ser auxiliado por estruturas de indexação especializadas. Este trabalho pretende investigar como a execução de cada um dos tipos de predicados afeta o desempenho de consultas STOLAP variando-se os índices utilizados, a ordem de execução dos predicados e a seletividade das consultas. Índices Bitmap de Junção auxiliarão na execução dos predicados convencionais e de algumas partes dos predicados temporais que também contarão com o auxílio de consultas SQL, enquanto os índices SB-index e HSB-index serão utilizados para auxiliar na execução dos predicados espaciais das consultas. O STB-index também será utilizado nas comparações e envolve ambos os predicados espacial e temporal. Espera-se obter uma análise das melhores opções de combinação de execução dos predicados em consultas STOLAP tendo em vista também a seletividade das consultas. Outra contribuição deste trabalho é a evolução do HSB-index para uma versão hierarquizada chamada HSTB-index e que servirá para complementar as opções de processamento de consultas STOLAP.
58

Redes Bayesianas aplicadas a estimação da taxa de prêmio de seguro agrícola de produtividade / Bayesian networks applied to estimation of yield insurance premium

Lucas Polo 08 July 2016 (has links)
Informações que caracterizam o risco quebra de produção agrícola são necessárias para a precificação de prêmio do seguro agrícola de produção e de renda. A distribuição de probabilidade da variável rendimento agrícola é uma dessas informações, em especial aquela que descreve a variável aleatória rendimento agrícola condicionada aos fatores de risco climáticos. Este trabalho objetiva aplicar redes Bayesianas (grafo acíclico direcionado, ou modelo hierárquico Bayesiano) a estimação da distribuição de probabilidade de rendimento da soja em alguns municípios do Paraná, com foco na analise comparativa de riscos. Dados meteorológicos (ANA e INMET, período de 1970 a 2011) e de sensoriamento remoto (MODIS, período de 2000 a 2011) são usados conjuntamente para descrever espacialmente o risco climático de quebra de produção. Os dados de rendimento usados no estudo (COAMO, período de 2001 a 2011) requerem agrupamento de todos os dados ao nível municipal e, para tanto, a seleção de dados foi realizada nas dimensões espacial e temporal por meio de um mapa da cultura da soja (estimado por SVM - support vector machine) e os resultados de um algoritmo de identificação de ciclo de culturas. A interpolação requerida para os dados de temperatura utilizou uma componente de tendência estimada por dados de sensoriamento remoto, para descrever variações espaciais da variável que são ofuscadas pelos métodos tradicionais de interpolação. Como resultados, identificou-se relação significativa entre a temperatura observada por estações meteorológicas e os dados de sensoriamento remoto, apoiando seu uso conjunto nas estimativas. O classificador que estima o mapa da cultura da soja apresenta sobre-ajuste para safras das quais as amostras usadas no treinamento foram coletadas. Além da seleção de dados, a identificação de ciclo também permitiu obtenção de distribuições de datas de plantio da cultura da soja para o estado do Paraná. As redes bayesianas apresentam grande potencial e algumas vantagens quando aplicadas na modelagem de risco agrícola. A representação da distribuição de probabilidade por um grafo facilita o entendimento de problemas complexos, por suposições de causalidade, e facilita o ajuste, estruturação e aplicação do modelo probabilístico. A distribuição log-normal demonstrou-se a mais adequada para a modelagem das variáveis de ambiente (soma térmica, chuva acumulada e maior período sem chuva), e a distribuição beta para produtividade relativa e índices de estado (amplitude de NDVI e de EVI). No caso da regressão beta, o parâmetro de precisão também foi modelado com dependência das variáveis explicativas melhorando o ajuste da distribuição. O modelo probabilístico se demonstrou pouco representativo subestimando bastante as taxas de prêmio de seguro em relação a taxas praticadas no mercado, mas ainda assim apresenta contribui para o entendimento comparativo de situações de risco de quebra de produção da cultura da soja. / Information that characterize the risk of crop losses are necessary to crop and revenue insurance underwriting. The probability distribution of yield is one of this information. This research applies Bayesian networks (direct acyclic graph, or hierarchical Bayesian model) to estimate the probability distribution of soybean yield for some counties in Paraná state (Brazil) with focus on risk comparative analysis. Meteorological data (ANA and INMET, from 1970 to 2011) and remote sensing data (MODIS, from 2001 to 2011) were used to describe spatially the climate risk of production loss. The yield data used in this study (COAMO, from 2001 to 2011) required grouping to county level and, for that, a process of data selection was performed on spatial and temporal dimensions by a crop map (estimated by SVM - support vector machine) and by the results of a crop cycle identification algorithm. The interpolation required to spatialize temperature required a trend component which was estimated by remote sensing data, to describe the spatial variations of the variable obfuscated by traditional interpolation methods. As results, a significant relation between temperature from meteorological stations and remote sensing data was found, sustaining the use of the supposed relation between the two variables. The soybean map classifier shown over-fitting for the crop seasons for which the training samples were collected. Besides the data collection, a seeding dates distribution of soybean in Paraná state was obtained from the crop cycle identification process. The Bayesian networks showed big potential and some advantages when applied to agronomic risk modeling. The representation of the probability distribution by graphs helps the understanding of complex problems, with causality suppositions, and also helps the fitting, structuring and application of the probabilistic model. The log-normal probability distribution showed to be the best to model environment variables (thermal sum, accumulated precipitation and biggest period without rain), and the beta distribution to be the best to model relative yield and state indexes (NDVI and EVI ranges). In the case of beta regression, the precision parameter was also modeled with explanation variables as dependencies increasing the quality of the distribution fitting. In the overall, the probabilistic model had low representativity underestimating the premium rates, however it contributes to understand scenarios with risk of yield loss for the soybean crop.
59

Classificação de sinais de eletroencefalograma usando máquinas de vetores suporte

Chagas, Sandro Luiz das 27 August 2009 (has links)
Made available in DSpace on 2016-03-15T19:38:14Z (GMT). No. of bitstreams: 1 Sandro Luiz das Chagas.pdf: 1694587 bytes, checksum: d10c7a5a95b65289731cab95f9b3478a (MD5) Previous issue date: 2009-08-27 / Electroencephalogram (EEG) is a clinical method widely used to study brain function and neurological disorders. The EEG is a temporal data series which records the electrical activity of the brain. The EEG monitoring systems create a huge amount of data; with this fact a visual analysis of the EEG is not feasible. Because of this, there is a strong demand for computational methods able to analyze automatically the EEG records and extract useful information to support the diagnostics. Herewith, it is necessary to design a tool to extract the relevant features within the EEG record and to classify the EEG based on these features. Calculation of statistics over wavelet coefficients are being used successfully to extract features from many kinds of temporal data series, including EEG signals. Support Vector Machines (SVM) are machine learning techniques with high generalization ability, and they have been successfully used in classification problems by several researches. This dissertation makes an analysis of the influence of feature vectors based on wavelet coefficients in the classification of EEG signal using different implementations of SVMs. / O eletroencefalograma (EEG) é um exame médico largamente utilizado no estudo da função cerebral e de distúrbios neurológicos. O EEG é uma série temporal que contém os registros de atividade elétrica do cérebro. Um grande volume de dados é gerado pelos sistemas de monitoração de EEG, o que faz com que a análise visual completa destes dados se torne inviável na prática. Com isso, surge uma grande demanda por métodos computacionais capazes de extrair, de forma automática, informação útil para a realização de diagnósticos. Para atender essa demanda, é necessária uma forma de extrair de um sinal de EEG as características relevantes para um diagnóstico e também uma forma de classificar o EEG em função destas características. O cálculo de estatísticas sobre coeficientes wavelet vem sendo empregado com sucesso na extração de características de diversos tipos de séries temporais, inclusive EEG. As máquinas de vetores de suporte (SVM do inglês Support Vector Machines) constituem uma técnica de aprendizado de máquina que possui alta capacidade de generalização e têm sido empregadas com sucesso em problemas de classificação por diversos pesquisadores. Nessa dissertação é feita uma análise do impacto da utilização de vetores de características baseados em coeficientes wavelet na classificação de EEG utilizando diferentes implementações de SVM.
60

Analytics on Indoor Moving Objects with Applications in Airport Baggage Tracking

Ahmed, Tanvir 20 June 2016 (has links)
A large part of people's lives are spent in indoor spaces such as office and university buildings, shopping malls, subway stations, airports, museums, community centers, etc. Such kind of spaces can be very large and paths inside the locations can be constrained and complex. Deployment of indoor tracking technologies like RFID, Bluetooth, and Wi-Fi can track people and object movements from one symbolic location to another within the indoor spaces. The resulting tracking data can be massive in volume. Analyzing these large volumes of tracking data can reveal interesting patterns that can provide opportunities for different types of location-based services, security, indoor navigation, identifying problems in the system, and finally service improvements. In addition to the huge volume, the structure of the unprocessed raw tracking data is complex in nature and not directly suitable for further efficient analysis. It is essential to develop efficient data management techniques and perform different kinds of analysis to make the data beneficial to the end user. The Ph.D. study is sponsored by the BagTrack Project (http://daisy.aau.dk/bagtrack). The main technological objective of this project is to build a global IT solution to significantly improve the worldwide aviation baggage handling quality. The Ph.D. study focuses on developing data management techniques for efficient and effective analysis of RFID-based symbolic indoor tracking data, especially for the baggage tracking scenario. First, the thesis describes a carefully designed a data warehouse solution with a relational schema sitting underneath a multidimensional data cube, that can handle the many complexities in the massive non-traditional RFID baggage tracking data. The thesis presents the ETL flow that loads the data warehouse with the appropriate tracking data from the data sources. Second, the thesis presents a methodology for mining risk factors in RFID baggage tracking data. The aim is to find the factors and interesting patterns that are responsible for baggage mishandling. Third, the thesis presents an online risk prediction technique for indoor moving objects. The target is to develop a risk prediction system that can predict the risk of an object in real-time during its operation so that the object can be saved from being mishandled. Fourth, the thesis presents two graph-based models for constrained and semi-constrained indoor movements, respectively. These models are used for mapping the tracking records into mapping records that represent the entry and exit times of an object at a symbolic location. The mapping records are then used for finding dense locations. Fifth, the thesis presents an efficient indexing technique, called the $DLT$-Index, for efficiently processing dense location queries as well as point and interval queries. The outcome of the thesis can contribute to the aviation industry for efficiently processing different analytical queries, finding problems in baggage management systems, and improving baggage handling quality. The developed data management techniques also contribute to the spatio-temporal data management and data mining field. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

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