1,721,073 research outputs found
Automatically Tailoring Semantics-Enabled Dimensions for Movement Data Warehouses
Get PDFThis paper proposes an automatic approach to build tailored dimensions for movement data warehouses based on views of existing hierarchies of objects (and their respective classes) used to semantically annotate movement segments. It selects the objects (classes) that annotate at least a given number of segments of a movement dataset to delineate hierarchy views for deriving tailored analysis dimensions for that movement dataset. Dimensions produced in this way can be quite smaller than the hierarchies from which they are extracted, leading to efficiency gains, among other potential benefits. Results of experiments with tweets semantically enriched with points of interest taken from linked open data collections show the viability of the proposed approach
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Busca em subespaços em varias dimensões
Get PDFOrientador: Pedro Jussieu de RezendeDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Ciencia da ComputaçãoResumo: o tema central deste trabalho é a pesquisa de soluções para problemas de busca em subespaços (range search), sob o enfoque de projeto de algoritmos eficientes e geometria computacional, considerando objetos de dados em forma de pontos dispersos num espaço multidimensional e explorando diversos formatos de subespaços de busca encontrados na literatura. O objetivo é reunir diversas formulações e métodos de solução em um compêndio, onde estes são descritos sob uma mesma ótica, com notação uniforme e de forma mais simples que nos textos originais, de modo a facilitar um estudo mais detalhado e comparações, no que diz respeito à natureza e ao funcionamento das soluções. Pretende-se com isso tornar as idéias provenientes da pesquisa atualmente em processo na área de algoritmos acessíveis de forma mais integrada e simples, tanto aos interessados na pesquisa de métodos mais eficientes e adequados para problemas em teoria da computação, quanto àqueles mais interessados na aplicação dessas idéias. Um estudo abrangente das soluções encontradas na literatura permite perceber diversas semelhanças de concepção nos métodos empregados. Freqüentemente, pode-se observar a ocorrência de abordagens e técnicas comuns em diversas situações. A estas abordagens e técnicas de aplicação geral atribuímos o nome de paradigmas de algoritmos. O estudo e a utilização de paradigmas de algoritmos possibilitam um certo grau de sistematização das soluções de problemas de busca em subespaços, uma vez que eles permitem encarar diversas soluções distintas, de diversas variações do problema como manifestações de um mesmo fundamento racional. Alem disso, o estudo de paradigmas é instrutivo, pois promove o desenvolvimento de raciocínios sistemáticos, aplicáveis na resolução de diversos problemas em computação.
A divisão do conteúdo é efetuada de maneira a fornecer primeiro o fundamento: teórico, necessário à compreensão dos métodos de solução, que são tratados posteriormente. No capítulo 1, são fornecidos os conceitos e classificações básicos, relativos a problemas de busca em geral e particularmente busca em subespaços, a fim de prover uma fundamentação teórica e situar a área de estudo.. No capítulo 2, são descritos alguns paradigmas de algoritmos aplicados a problemas de busca em subespaços, com o intuito de prover ao leitor maneiras alternativaS de relacionar as soluções apresentadas posteriormente, induzindo-o a desenvolver raciocínios que lhe habilitem a perceber os fundamentos e técnicas em comum. Nos capítulos 3 a 6, são abordados os sub.problemas caracterizados pelos formatos clássicos de subespaços de busca encontrados na literatura, ordenados da maneira que parece mais conveniente e que reflete a complexidade das soluções, a natureza das mesmas e sua evolução histórica. Em cada um destes capítulos, os sub-problemas são discutidos em detalhes, algumas soluções e limites inferiores são descritos superficialmente e há uma seção de notas bibliográficas, com referências para assuntos específicos. Finalmente, no capítulo 7, são sintetizadas as contribuições do trabalho e relacionados alguns assuntos para possíveis extensões no futuro.Abstract: The main, objective of this work is the study of solutions found in the literature to range search, from the view point of algorithm design and computational geometry, considering only data objects; in the form of points embedded1 in a multidimensional space, and investigating various shapes of ranges. Several formulations and solutions to range search problems are surveyed. These are described under one abstract view, with uniform notation and in a form hopefully clearer than, the original sources, in such way that comparisons of the nature and functionality of the solutions and more detailed studies may be facilitated. Our purpose is to make the ideas deriving from the research on range search available in a more integrated and simpler way, to people interested in the discovery of more suitable and. efficient methods for problems in theoretical computer science as well as to those interested in the applications of these ideas. A wide study of the solutions found in the literature shows many conceptual similarities in the employed methods. Frequently, the same approaches and' techniques are seen in distinct situations. These general purpose approaches and techniques are called "algorithm paradigms". The study and application of these paradigms allow a certain level of generalization of the solutions to range search problems, because they allow one to perceive several solutions of vario1ls instances of a general problem as the manifestation of the same rationale. The study of algorithm paradigms is instructive in its own right, since it propitiates the development of systematic reasoning, useful in the solution of many problems in computer science. The contents herein are arranged so as to first give the theoretical basis necessary to understanding the methods given later. In chapter 1, we provide the basic concepts and classifications related to search problems in general and to range search in particular, and establish the scope of our research. In chapter 2, we describe some algorithm paradigms applied to range search problems, with the purpose of supplying the reader with alternative ways of establishing connections among the solutions presented later leading him to develop a reasoning that allows the identification of the fundamentals and techniques shared by tile sol1itions. In, chapters 3 to 6, we deal with the variations of' the range search problem characterized by the classical shapes of ranges considered in the literature. These chapters are arranged in a convenient way in order to reflect the complexity ofthe discussed solutions, their nature and the historical evolution. In each one of these chapters the problems are discussed in detail, some solutions and lower bounds are briefly described and bibliographic notes containing references to specific subjects are presented. Finally, in chapter 7, we summarize the contributions of this work and extensions that can be undertaken in the future.MestradoMestre em Ciência da Computaçã
A abordagem POESIA para a integração de dados e serviços na Web semantica
Get PDFOrientador: Claudia Bauzer MedeirosTese (doutorado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: POESIA (Processes for Open-Ended Systems for lnformation Analysis), a abordagem proposta neste trabalho, visa a construção de processos complexos envolvendo integração e análise de dados de diversas fontes, particularmente em aplicações científicas. A abordagem é centrada em
dois tipos de mecanismos da Web semântica: workflows científicos, para especificar e compor serviços Web; e ontologias de domínio, para viabilizar a interoperabilidade e o gerenciamento semânticos dos dados e processos. As principais contribuições desta tese são: (i) um arcabouço teórico para a descrição, localização e composição de dados e serviços na Web, com regras para verificar a consistência semântica de composições desses recursos; (ii) métodos baseados em ontologias de domínio para auxiliar a integração de dados e estimar a proveniência de dados em processos cooperativos na Web; (iii) implementação e validação parcial das propostas, em urna aplicação real no domínio de planejamento agrícola, analisando os benefícios e as limitações de eficiência e escalabilidade da tecnologia atual da Web semântica, face a grandes volumes de dadosAbstract: POESIA (Processes for Open-Ended Systems for Information Analysis), the approach proposed in this work, supports the construction of complex processes that involve the integration and analysis of data from several sources, particularly in scientific applications. This approach is centered in two types of semantic Web mechanisms: scientific workflows, to specify and compose Web services; and domain ontologies, to enable semantic interoperability and management of data and processes. The main contributions of this thesis are: (i) a theoretical framework to describe, discover and compose data and services on the Web, inc1uding mIes to check the semantic consistency of resource compositions; (ii) ontology-based methods to help data integration and estimate data provenance in cooperative processes on the Web; (iii) partial implementation and validation of the proposal, in a real application for the domain of agricultural planning, analyzing the benefits and scalability problems of the current semantic Web technology, when faced with large volumes of dataDoutoradoCiência da ComputaçãoDoutor em Ciência da Computaçã
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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