Time series datasets are useful in a wide range of diverse real world applications. Retrieving or querying from a collection of time series is a fundamental task, with a key example being the similarity query. A similarity query returns all time series from the collection that are similar to a given reference time series. This type of query is particularly useful in prediction and forecasting applications. / A key challenge for similarity queries is efficiency and for large datasets, it is important to develop efficient indexing techniques. Existing approaches in this area are mainly based on the Generic Multimedia Indexing Method (GEMINI), which is a framework that uses spatial indexes such as the R-tree to index reduced time series. For processing a similarity query, the index is first used to prune candidate time series using a lower bounding distance. Then, all remaining time series are compared using the original similarity measure, to derive the query result. Performance within this framework depends on the tightness of the lower bounding distance with respect to the similarity measure. Indeed much work has been focused on representation and dimensionality reduction, in order to provide a tighter lower bounding distance. / Existing work, however, has not used employed dimensionality reduction in a flexible way, requiring all time series to be reduced to have the same dimension. In contrast, in this thesis, we investigate the possibility of allowing a variable dimension reduction. To this end, we develop a new and more flexible tree based indexing structure called the Multi-Resolution Index (MR-Index), which allows dimensionality to vary across different levels of the tree. We provide efficient algorithms for querying, building and maintaining this structure. Through an experimental analysis, we show that the MR-Index can deliver improved query efficiency compared to the traditional R-tree index, using both the Euclidean and dynamic time warping similarity measures.

This thesis looks at the problem of reconstructing a single surface representation from multiple range images acquired from a terrestrial laser scanner. A solution to this problem is important to industries such as mining, where accurate spatial measurement is required for mapping and volumetric calculations. Laser scanners for 3D measurement are now commercially available and software for deriving useful information from the data these devices generate is essential. A reconstruction technique based on an implicit surface representation of the range images and a polygonisation algorithm called marching triangles has been implemented in software and its performance investigated. This work improves upon the existing techniques in that it takes into account the particular differences of terrestrial range data as compared with data from small scale laser scanners. The implementation is robust with respect to noisy data and environments and requires minimal user input. A new approach to 3D spatial indexing is also developed to allow rapid evaluation of the true closest point to a surface which is the basis of the signed distance function implicit surface representation. A new technique for locating step discontinuities in the range image is presented, which caters for the varying sampling densities of terrestrial range images. The algorithm is demonstrated using representative range images acquired for surface erosion monitoring and for underground mine surveying. The results indicate that this reconstruction technique represents an improvement over current techniques for this type of range data. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1169106 / Thesis (Ph.D.) -- University of Adelaide, School of Computer Science, 2005

This thesis looks at the problem of reconstructing a single surface representation from multiple range images acquired from a terrestrial laser scanner. A solution to this problem is important to industries such as mining, where accurate spatial measurement is required for mapping and volumetric calculations. Laser scanners for 3D measurement are now commercially available and software for deriving useful information from the data these devices generate is essential. A reconstruction technique based on an implicit surface representation of the range images and a polygonisation algorithm called marching triangles has been implemented in software and its performance investigated. This work improves upon the existing techniques in that it takes into account the particular differences of terrestrial range data as compared with data from small scale laser scanners. The implementation is robust with respect to noisy data and environments and requires minimal user input. A new approach to 3D spatial indexing is also developed to allow rapid evaluation of the true closest point to a surface which is the basis of the signed distance function implicit surface representation. A new technique for locating step discontinuities in the range image is presented, which caters for the varying sampling densities of terrestrial range images. The algorithm is demonstrated using representative range images acquired for surface erosion monitoring and for underground mine surveying. The results indicate that this reconstruction technique represents an improvement over current techniques for this type of range data. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1169106 / Thesis (Ph.D.) -- University of Adelaide, School of Computer Science, 2005

Thesis (M.S.) -- Central Connecticut State University, 2008. / Thesis advisor: Roger Bilisoly. "... in partial fulfillment of the requirements for the degree of Master of Science in Data Mining." Includes bibliographical references (leaves 122-127). Also available via the World Wide Web.

Dissertation (MCIS - Computer and Information Sciences) -- AUT University, 2008. / Includes bibliographical references. Also held in print (46 leaves ; 30 cm.) in City Campus Theses Collection (T 005.74 DAM)

Thesis--Columbia University, 1960. / Bibliography: l. 170-175.

Thesis (Ph. D.)--Drexel University, 1985. / Vita. Description based on print version record. Includes bibliographical references (leaves 182-185).

Given the growth and outreach of new information, communication, computing and electronic technologies in various dimensions, the amount of data has explosively increased in the recent years. Centralised systems suffer some limitations to dealing with this issue due to all data is stored in central data centres. Thus, decentralised systems are getting more attention and increasing in popularity. Moreover, efficient service discovery mechanisms have naturally become an essential component in both large-scale and small-scale decentralised systems and. This research study is aimed at modelling a novel efficient indexing and searching model for service discovery in decentralised environments comprising numerous repositories with massive stored services. The main contributions of this research study can be summarised in three components: a novel distributed multilevel indexing model, an optimised searching algorithm and a new simulation environment. Indexing model has been widely used for efficient service discovery. For instance; the inverted index is one of the popular indexing models used for service retrieval in consistent repositories. However, redundancies are inevitable in the inverted index which is significantly time-consuming in the service discovery and retrieval process. This theeis proposes a novel distributed multilevel indexing model (DM-index), which offers an efficient solution for service discovery and retrieval in distributed service repositories comprising massive stored services. The architecture of the proposed indexing model encompasses four hierarchical levels to eliminate redundancy information in service repositories, to narrow the searching space and to reduce the number of traversed services whilst discovering services. Distributed Hash Tables have been widely used to provide data lookup services with logarithmic message costs which only require maintenance of limited amounts of routing states. This thesis develops an optimised searching algorithm, named Double-layer No-redundancy Enhanced Bi-direction Chord (DNEB-Chord), to handle retrieval requests in distributed destination repositories efficiently. This DNEB-Chord algorithm achieves faster routing performances with the double-layer routing mechanism and optimal routing index. The efficiency of the developed indexing and searching model is evaluated through theoretical analysis and experimental evaluation in a newly developed simulation environment, named Distributed Multilevel Bi-direction Simulator (DMBSim), which can be used as cost efficient tool for exploring various service configurations, user retrieval requirements and other parameter settings. Both the theoretical validation and experimental evaluations demonstrate that the service discovery efficiency of the DM-index outperforms the sequential index and inverted index configurations. Furthermore, the experimental evaluation results demostrate that the DNEB-Chord algorithm performs better than the Chord in terms of reducing the incurred hop counts. Finally, simulation results demonstrate that the proposed indexing and searching model can achieve better service discovery performances in large-scale decentralised environments comprising numerous repositories with massive stored services.

Made available in DSpace on 2014-11-10T11:09:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-05-22Bitstream added on 2014-11-10T11:58:46Z : No. of bitstreams: 1 000795209.pdf: 1727511 bytes, checksum: 1598f0827cc68fc9ef02db6acddf93cd (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A necessidade de aprimoramento das práticas, dos instrumentos, processos e produtos que envolvem o tratamento temático da informação, propicia investigações que objetivam contribuir para o desenvolvimento da prática profissional da análise de assunto na catalogação. A proposição de nossa pesquisa é aprofundar estudos acerca da análise de assunto na catalogação de assunto, sob uma perspectiva de autores nacionais e internacionais, de normalização e de sociedade de profissionais para identificar diretrizes da análise de assunto na catalogação de assunto que propiciem o aprimoramento do processo de indexação na política de indexação em bibliotecas universitárias. Possui como objetivos específicos aprofundar estudos teóricos e metodológicos voltados para a catalogação de assunto e para a análise de assunto; realizar estudos sobre normalizações em contexto de bibliotecas universitárias; explorar a análise de assunto utilizando aspectos da abordagem sociocognitiva, da semiótica e da linguística textual e conhecer os processos da análise de assunto. Para isso, realizou-se uma análise exaustiva e crítica da literatura existente e deste modo aplicou-se a metodologia do protocolo verbal “pensar alto” e a pesquisa etnográfica em dezesseis bibliotecas universitárias, sendo seis na área de Medicina e seis na área da Ciência da Computação no Brasil e quatro na área de Biblioteconomia e Documentação na Espanha. Posteriormente, realizou-se uma tabulação e análise dos protocolos verbais individuais e das pesquisas etnográficas, que resultou ser revelador para conhecer o processo de análise de assunto, que propiciaram a discussão de elementos como especificidade do vocabulário controlado, política de indexação, exaustividade e especificidade, hábitos, experiência colateral, cognição profissional, qualidade da análise de assunto, usuários, acesso a linguagem documentária, leitura documentária... / La necesidad de la mejora de las prácticas, herramientas, procesos y productos relacionados con el análisis documental de contenido, fomenta el desarrollo de la práctica profesional de la asignación de materias en la catalogación. El objetivo de la investigación es profundizar en el estudio del análisis de asignación de materias con el fin de identificar recomendaciones y tareas que proporcionen la mejora del proceso de indización y el diseño de las políticas de indización en las bibliotecas universitarias. Como objetivos específicos se pretende analizar las teorias y metodologias del análisis de materias en la catalogación; estudiar la normalización en el ámbito de las bibliotecas universitarias; explorar los procesos de asignación de materias usando la perspectiva sociocognitiva, de la semiótica y de la lingüística textual y conocer los procesos de la asignación de materias. Para todo ello, se realizo un análisis exhaustivo y crítico de la literatura existente y se aplicó la metodología del protocolo verbal “pensar en alto” y la investigación etnográfica en dieciséis bibliotecas universitarias, en seis de Medicina y seis de Informática en Brasil y en cuatro de Biblioteconomía y Documentación en España. Posteriormente, se llevó a cabo uma tabulación y análisis de los protocolos verbales individuales y de las entrevistas, que resultó ser revelador para conocer el proceso de asignación de materias, lo que ha permitido detectar interessantes aspectos sobre la especificidad del vocabulario controlado, la política de indización, la exhaustividad y especificidad en la indización, los hábitos de los profesionales, la cognición profesional, la calidad en la asignación de materias, la lectura documental o la identificación y selección de conceptos, entre otros aspectos. Con los resultados obtenidos también se han podido elaborar directrices para llevar a cabo la asignación de materias en... / The need for improvement of practices, tools, processes and products involving the subject representation, promotes research aimed to contribute to the development of professional practice in the subject analysis in the subject cataloguing. The proposition of our research is to deepen the subject analysis, from the perspective of national and international authors, standardization and professional society guidelines to identify of the analysis of subject cataloguing subject that facilitate the improvement of indexing process in indexing policy in university libraries. Have specific objectives aimed to deepen theoretical and methodological studies for subject cataloging and subject analysis; conduct studies on normalization in the context of university libraries; explore the subject analysis using aspects of socio-cognitive approach, semiotics and textual linguistics and understand the processes of subject analysis. For this, we performed an exhaustive analysis and critique of the existing literature and applied the methodology of the oral protocol “think aloud” and ethnographic research in sixteen university libraries, six in Medicine and six in the field of Computer Science in Brazil and four in the area of Librarianship and Documentation in Spain. Subsequently, there was a tabulation and analysis of individual verbal protocols and ethnographic research, which proved to be revealing to know the process of subject analysis, that have led to the discussion of elements such as specificity of controlled vocabulary, indexing policy, completeness and specificity, habits, collateral experience, professional cognition, quality of subject analysis, documentary reading, identification and selection of concepts, these concepts were discussed from the context of social cognitive cataloger, theory and standards. With the results we provide guidelines to develop the subject analysis in university libraries. The process of the subject analysis shows to be...

Orientador: Mariângela Spotti Lopes Fujita / Banca: Isidoro Gil Leiva / Banca: Dulce Amélia de Brito Neves / Banca: Brígida Maria Nogueira Cervantes / Banca: Carlos Cândido de Almeida / Resumo: A necessidade de aprimoramento das práticas, dos instrumentos, processos e produtos que envolvem o tratamento temático da informação, propicia investigações que objetivam contribuir para o desenvolvimento da prática profissional da análise de assunto na catalogação. A proposição de nossa pesquisa é aprofundar estudos acerca da análise de assunto na catalogação de assunto, sob uma perspectiva de autores nacionais e internacionais, de normalização e de sociedade de profissionais para identificar diretrizes da análise de assunto na catalogação de assunto que propiciem o aprimoramento do processo de indexação na política de indexação em bibliotecas universitárias. Possui como objetivos específicos aprofundar estudos teóricos e metodológicos voltados para a catalogação de assunto e para a análise de assunto; realizar estudos sobre normalizações em contexto de bibliotecas universitárias; explorar a análise de assunto utilizando aspectos da abordagem sociocognitiva, da semiótica e da linguística textual e conhecer os processos da análise de assunto. Para isso, realizou-se uma análise exaustiva e crítica da literatura existente e deste modo aplicou-se a metodologia do protocolo verbal "pensar alto" e a pesquisa etnográfica em dezesseis bibliotecas universitárias, sendo seis na área de Medicina e seis na área da Ciência da Computação no Brasil e quatro na área de Biblioteconomia e Documentação na Espanha. Posteriormente, realizou-se uma tabulação e análise dos protocolos verbais individuais e das pesquisas etnográficas, que resultou ser revelador para conhecer o processo de análise de assunto, que propiciaram a discussão de elementos como especificidade do vocabulário controlado, política de indexação, exaustividade e especificidade, hábitos, experiência colateral, cognição profissional, qualidade da análise de assunto, usuários, acesso a linguagem documentária, leitura documentária... / Abstract: La necesidad de la mejora de las prácticas, herramientas, procesos y productos relacionados con el análisis documental de contenido, fomenta el desarrollo de la práctica profesional de la asignación de materias en la catalogación. El objetivo de la investigación es profundizar en el estudio del análisis de asignación de materias con el fin de identificar recomendaciones y tareas que proporcionen la mejora del proceso de indización y el diseño de las políticas de indización en las bibliotecas universitarias. Como objetivos específicos se pretende analizar las teorias y metodologias del análisis de materias en la catalogación; estudiar la normalización en el ámbito de las bibliotecas universitarias; explorar los procesos de asignación de materias usando la perspectiva sociocognitiva, de la semiótica y de la lingüística textual y conocer los procesos de la asignación de materias. Para todo ello, se realizo un análisis exhaustivo y crítico de la literatura existente y se aplicó la metodología del protocolo verbal "pensar en alto" y la investigación etnográfica en dieciséis bibliotecas universitarias, en seis de Medicina y seis de Informática en Brasil y en cuatro de Biblioteconomía y Documentación en España. Posteriormente, se llevó a cabo uma tabulación y análisis de los protocolos verbales individuales y de las entrevistas, que resultó ser revelador para conocer el proceso de asignación de materias, lo que ha permitido detectar interessantes aspectos sobre la especificidad del vocabulario controlado, la política de indización, la exhaustividad y especificidad en la indización, los hábitos de los profesionales, la cognición profesional, la calidad en la asignación de materias, la lectura documental o la identificación y selección de conceptos, entre otros aspectos. Con los resultados obtenidos también se han podido elaborar directrices para llevar a cabo la asignación de materias en... / The need for improvement of practices, tools, processes and products involving the subject representation, promotes research aimed to contribute to the development of professional practice in the subject analysis in the subject cataloguing. The proposition of our research is to deepen the subject analysis, from the perspective of national and international authors, standardization and professional society guidelines to identify of the analysis of subject cataloguing subject that facilitate the improvement of indexing process in indexing policy in university libraries. Have specific objectives aimed to deepen theoretical and methodological studies for subject cataloging and subject analysis; conduct studies on normalization in the context of university libraries; explore the subject analysis using aspects of socio-cognitive approach, semiotics and textual linguistics and understand the processes of subject analysis. For this, we performed an exhaustive analysis and critique of the existing literature and applied the methodology of the oral protocol "think aloud" and ethnographic research in sixteen university libraries, six in Medicine and six in the field of Computer Science in Brazil and four in the area of Librarianship and Documentation in Spain. Subsequently, there was a tabulation and analysis of individual verbal protocols and ethnographic research, which proved to be revealing to know the process of subject analysis, that have led to the discussion of elements such as specificity of controlled vocabulary, indexing policy, completeness and specificity, habits, collateral experience, professional cognition, quality of subject analysis, documentary reading, identification and selection of concepts, these concepts were discussed from the context of social cognitive cataloger, theory and standards. With the results we provide guidelines to develop the subject analysis in university libraries. The process of the subject analysis shows to be... / Doutor