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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.
141

CPR: Complex Pattern Ranking for Evaluating Top-k Pattern Queries over Event Streams

January 2011 (has links)
abstract: Most existing approaches to complex event processing over streaming data rely on the assumption that the matches to the queries are rare and that the goal of the system is to identify these few matches within the incoming deluge of data. In many applications, such as stock market analysis and user credit card purchase pattern monitoring, however the matches to the user queries are in fact plentiful and the system has to efficiently sift through these many matches to locate only the few most preferable matches. In this work, we propose a complex pattern ranking (CPR) framework for specifying top-k pattern queries over streaming data, present new algorithms to support top-k pattern queries in data streaming environments, and verify the effectiveness and efficiency of the proposed algorithms. The developed algorithms identify top-k matching results satisfying both patterns as well as additional criteria. To support real-time processing of the data streams, instead of computing top-k results from scratch for each time window, we maintain top-k results dynamically as new events come and old ones expire. We also develop new top-k join execution strategies that are able to adapt to the changing situations (e.g., sorted and random access costs, join rates) without having to assume a priori presence of data statistics. Experiments show significant improvements over existing approaches. / Dissertation/Thesis / M.S. Computer Science 2011
142

Os efeitos do ranking do Exame Nacional do Ensino M?dio (ENEM) na realidade das escolas de Te?filo Otoni nas perspectivas dos atores envolvidos

Rosa, Jose Gaspar 21 October 2016 (has links)
Submitted by Raniere Barreto (raniere.barros@ufvjm.edu.br) on 2018-05-15T17:17:03Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_gaspar_rosa.pdf: 944028 bytes, checksum: 91b27d128ff9013b6aae81db12dcbaa0 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-05-15T18:53:23Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_gaspar_rosa.pdf: 944028 bytes, checksum: 91b27d128ff9013b6aae81db12dcbaa0 (MD5) / Made available in DSpace on 2018-05-15T18:53:23Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_gaspar_rosa.pdf: 944028 bytes, checksum: 91b27d128ff9013b6aae81db12dcbaa0 (MD5) Previous issue date: 2016 / O presente trabalho tem como finalidade analisar os efeitos do ranking do Enem na pr?tica pedag?gica e no curr?culo escolar do ensino m?dio nas escolas p?blicas estaduais do munic?pio de Te?filo Otoni, no estado de Minas Gerais a partir da percep??o dos atores envolvidos (docentes e gestores) no ano 2016. Como objetivos espec?ficos foram analisadas as pol?ticas educacionais na contemporaneidade; as diretrizes do ensino m?dio e o papel do Enem no cumprimento dessas diretrizes. Foram tamb?m identificados os efeitos do Enem na realidade do ensino m?dio das escolas a partir da percep??o dos docentes e gestores das escolas p?blicas de Te?filo Otoni, a partir da cria??o desse exame. Para atender aos objetivos propostos, realizou-se uma pesquisa bibliogr?fica a partir dos estudos divulgados sobre o tema, an?lise documental da legisla??o pertinente e das principais orienta??es emanadas do Minist?rio da Educa??o acerca desse exame e pesquisa de campo nas escolas do munic?pio. Foram realizadas entrevistas semiestruturadas com quatro gestores e aplicados vinte e tr?s question?rios para os docentes das escolas: Coqueiros, Urucuia, Santana e S?o Jorge. Os dados revelaram que o ranqueamento das escolas est? provocando uma altera??o das pr?ticas escolares com vistas a se situarem em posi??o melhor na divulga??o do pr?ximo ranqueamento. Mostraram, tamb?m, a exist?ncia de competi??o entre escolas e o estreitamento curricular, uma vez que as a??es de sala de aula s?o planejadas com ?nfase em projetos de revis?o de conte?dos com o objetivo de preparar o estudante apenas para se sair bem na prova. Revelaram, igualmente, que as escolas v?m criando um curr?culo informal voltado especialmente para preparar os estudantes para obterem bons resultados no Enem deixando de lado o objetivo principal do curr?culo que ? a forma??o humana e a qualidade do ensino. Isso porque os resultados desse exame t?m provocado altera??es na rotina das escolas por meio da adequa??o do curr?culo e das pr?ticas pedag?gicas atreladas a esses resultados. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Tecnologia, Sa?de e Sociedade, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The present project intend to analyze the effects of the Enem ranking on pedagogical practices and also on educational curriculum of the publics high schools of the city of Teofilo Otoni, in Minas Gerais state, by the feelings of the (teachers and managers) in the year 2016. As the main objective were analyzed the current educational policies, the guidelines of high school education, and the influence of Enem on the achievement of what was proposed. The effects of Enem into the reality of the public high schools of the city were identified by the feelings of teachers and managers. To achieve the proposed goals, a bibliographic research were done involving the studies about this theme, the main guidelines published by the Education Ministry, the analyze of relevant legislation and also field research on the schools. The field research has been based on semi-structured interview with four managers, and the application of twenty three quizzes for the teachers of the schools: Coqueiros, Urucuia, Santana and S?o Jorge. The data revealed that the schools practices have been changing in an act tolook for better positions on the Enem ranking. They also showed the crescent competition between the schools and the intake of the curriculum once the acts on class are planed just to prepare the students for the test. This situation ends up creating a non-formal curriculum once the main objective of the institutions became a better position, leaving apart the most important value of public education, the human formation and quality of education.
143

Visibilidade web de universidades

Klinger, Augusto January 2011 (has links)
Visibilidade Web é a área de estudo das medidas de visibilidade de organizações, termos ou documentos na web, sendo um dos campos de pesquisa da ciência de Webmetria. Neste trabalho, uma fórmula para o cálculo de visibilidade na web é proposta, baseando-se na visão proporcionada por diferentes motores de busca. O resultado final é um indicador de Visibilidade Web para universidades. São apresentados e analisados rankings de universidades do mundo todo encontrados na web, tais como o ARWU, o WR e o THE. Tais rankings trabalham com indicadores compostos, mas abordam a questão da visibilidade na rede de maneiras diferentes. Também são discutidos alguns trabalhos recentes no campo de Visibilidade Web. O indicador elaborado baseia-se na classificação do site oficial da universidade nos buscadores como meio de pontuar a visibilidade, valendo-se de metabusca. Um método de fusão de rankings é utilizado para a pontuação. Siglas de universidades brasileiras foram submetidas ao cálculo de visibilidade e classificadas, mostrando uma aplicação da fórmula no mundo real. Dois rankings foram construídos, um deles apontando falhas no método proposto e o segundo contornando o problema encontrado, apresentando uma classificação justa, coerente com a realidade e com outros rankings de universidades brasileiras. A principal contribuição do trabalho é a definição de um indicador de visibilidade na web que mostra como são classificadas as instituições através dos principais pontos de entrada da rede: os motores de busca. / Web Visibility is the area of study of visibility measures of organizations, terms or documents on the web, one of the fields of the Webmetrics science. In this work, a formula for the calculation of visibility on the web is proposed, based on the vision provided by different search engines. The result is an indicator of Web Visibility for universities. In related works section are presented and analyzed rankings of universities around the world from the web, such as ARWU, WR and THE. Such rankings work with composite indicators, but address the issue of visibility on the network in different ways. Also are covered some resent works in the field of Web Visibility. The indicator developed is based on the classification of the universities’ official website in search engines as a means of scoring the visibility, using a metasearch engine. A method of rankings fusion is used for the scoring process. Acronyms of Brazilian universities were subjected to the calculation of visibility and classified, showing an application of the formula in the real world. Two rankings were built, one of them pointing out flaws in the proposed method and another solving the problem encountered with a fair rating, consistent with reality and with other rankings of universities. The main contribution of this work is a Web Visibility indicator that shows how the institutions are classified by the main entry points of the network: the search engines.
144

Dissolução de Foraminíferos Quaternários do Atlântico Sul: da perda de CaCO3 ao ganho de informação paleoceanográfica

Petró, Sandro Monticelli January 2018 (has links)
Estudos paleoceanográficos são baseados em indicadores indiretos, ou seja, informações sedimentológicas, paleontológicas e geoquímicas que refletem as condições ambientais dos oceanos no passado geológico. Processos tafonômicos como a dissolução podem enviesar a informação contida nestes indicadores. Porém, quando corretamente identificada, a dissolução pode se tornar uma ferramenta para caracterizar mudanças oceanográficas, como variações na distribuição das massas d’água e a acidificação dos oceanos. O objetivo deste estudo é entender como ocorre este enviesamento, identificar indicadores que determinam a presença ou ausência da dissolução e identificar alterações oceanográficas no Quaternário tardio da Bacia de Pelotas em função deste processo. Esta tese compreende várias etapas, incluindo a realização de experimentos de dissolução em varias espécies de foraminíferos provenientes do oeste do Atlântico Sul, a comparação entre dados de fauna de foraminíferos planctônicos de sedimento com as condições ambientais do oceano Atlântico Sul e, finalmente, as análises de testemunhos do Quaternário tardio da Bacia de Pelotas (foraminíferos, cocolitoforídeos, teor de carbonato, granulometria, δ18O, AMS 14C). Os experimentos geraram um ranking de susceptibilidade à dissolução para foraminíferos, identificando Orbulina universa e Hoeglundina sp. como bons indicadores de pouca dissolução, além de identificar a razão entre foraminíferos planctônicos e bentônicos como imprópria para indicar o grau de dissolução. A análise da fauna de foraminíferos planctônicos do Atlântico Sul identificou maior enviesamento por condições ambientais de fundo em áreas com massas d’água mais corrosivas provenientes do sul, bem como o viés observado nas espécies frágeis pode ser relacionado aos erros em estimativas de paleotemperaturas baseadas em censos de fauna. Baseado nos indicadores aqui elaborados, combinado com outros indicadores comuns, as alterações oceanográficas na Bacia de Pelotas indicam um aumento da dissolução em períodos glaciais em função do avanço da Água Antartica de Fundo e da Água Circumpolar Superior. Finalmente, na parte conceitual desta tese, é proposta uma definição de zona tafonômicamente ativa para sistemas pelágicos, que deve considerar a coluna d’água como seu limite superior. / Paleoceanographic studies are based on proxy data, i.e. sedimentological, paleontological and geochemical information that reflect the environmental conditions of the oceans in the geological past. Taphonomic processes such as dissolution may bias the information contained in these proxies. However, when correctly identified, dissolution can become a tool to characterize oceanographic changes, such as variations in the water masses distribution and acidification of the oceans. The purpose of this study is to understand how this bias occurs, to identify proxies that determine the presence or absence of dissolution and to identify late Quaternary oceanographic changes in the Pelotas Basin as a function of this process. This thesis comprises several stages, including dissolution experiments on several foraminifera species from the western South Atlantic, comparison between sediment plankton foraminifera fauna data with environmental conditions of the South Atlantic Ocean, and finally, the analyses of late Quaternary of the Pelotas Basin cores (foraminifera, coccolith, carbonate content, grain size, δ18O, and AMS 14C). The experiments generated a ranking of susceptibility to dissolution for foraminifera, identifying Orbulina universa and Hoeglundina sp. as good proxies of low dissolution, besides identifying the planktonic and benthic foraminifera ratio as inappropriate for indicating the degree of dissolution. The analysis of the planktonic foraminifera fauna of the South Atlantic identified greater bias due to bottom environmental conditions in areas with more corrosive water masses from the south, as well as the observed bias in fragile species may be related to errors in paleotemperature estimates based on fauna census counts. Based on the proxies developed here, and other indicators frequently used, the late Quaternary oceanographic changes in the Pelotas Basin indicate an increase of the dissolution in glacial periods due to the advance of Antarctic Bottom Water and Upper Circumpolar Deep Water. Finally, in the conceptual part of this thesis, a taphonomically active zone for pelagic systems is proposed, which should consider the water column as its upper limit.
145

VersionsRank : escores de reputação de páginas web baseados na detecção de versões

Silva, Glauber Rodrigues da January 2009 (has links)
Os motores de busca utilizam o WebGraph formado pelas páginas e seus links para atribuir reputação às páginas Web. Essa reputação é utilizada para montar o ranking de resultados retornados ao usuário. No entanto, novas versões de páginas com uma boa reputação acabam por distribuir os votos de reputação entre todas as versões, trazendo prejuízo à página original e também as suas versões. O objetivo deste trabalho é especificar novos escores que considerem todas as versões de uma página Web para atribuir reputação para as mesmas. Para atingir esse objetivo, foram propostos quatro escores que utilizam a detecção de versões para atribuir uma reputação mais homogênea às páginas que são versões de um mesmo documento. Os quatro escores propostos podem ser classificados em duas categorias: os que realizam mudanças estruturais no WebGraph (VersionRank e VersionPageRank) e os que realizam operações aritméticas sobre os escores obtidos pelo algoritmo de PageRank (VersionSumRank e VersionAverageRank). Os experimentos demonstram que o VersionRank tem desempenho 26,55% superior ao PageRank para consultas navegacionais sobre a WBR03 em termos de MRR, e em termos de P@10, o VersionRank tem um ganho de 9,84% para consultas informacionais da WBR99. Já o escore VersionAverageRank, apresentou melhores resultados na métrica P@10 para consultas informacionais na WBR99 e WBR03. Na WBR99, os ganhos foram de 6,74% sobre o PageRank. Na WBR03, para consultas informacionais aleatórias o escore VersionAverageRank obteve um ganho de 35,29% em relação ao PageRank. / Search engines use WebGraph formed by the pages and their links to assign reputation to Web pages. This reputation is used for ranking show for the user. However, new versions of pages with a good reputation distribute your votes of reputation among all versions, damaging the reputation of original page and also their versions. The objective of this work is to specify the new scores to consider all versions of a Web page to assign reputation to them. To achieve this goal, four scores were proposed using the version detection to assign a more homogeneous reputation to the pages that are versions of the same document. The four scores proposed can be classified into two categories: those who perform structural changes in WebGraph (VersionRank and VersionPageRank) and those who performs arithmetic operations on the scores obtained by the PageRank algorithm (VersionSumRank and VersionAverageRank). The experiments show that the performance VersionRank is 26.55% higher than the PageRank for navigational queries on WBR03 in terms of MRR, and in terms of P@10, the VersionRank has a gain of 9.84% for the WBR99 informational queries. The score VersionAverageRank showed better results in the metric P@10 for WBR99 and WBR03 information queries. In WBR99, it had a gain of 6.74% compared to PageRank. In WBR03 for random informational queries, VersionAverageRank showed an increase of 35.29% compared to PageRank.
146

Productividad de publicaciones académicas en Administración y su influencia en los rankings de MBA latinoamericanos.

López Quinteros, Regina, Machuca Pinto, Carolina January 2004 (has links)
No description available.
147

VersionsRank : escores de reputação de páginas web baseados na detecção de versões

Silva, Glauber Rodrigues da January 2009 (has links)
Os motores de busca utilizam o WebGraph formado pelas páginas e seus links para atribuir reputação às páginas Web. Essa reputação é utilizada para montar o ranking de resultados retornados ao usuário. No entanto, novas versões de páginas com uma boa reputação acabam por distribuir os votos de reputação entre todas as versões, trazendo prejuízo à página original e também as suas versões. O objetivo deste trabalho é especificar novos escores que considerem todas as versões de uma página Web para atribuir reputação para as mesmas. Para atingir esse objetivo, foram propostos quatro escores que utilizam a detecção de versões para atribuir uma reputação mais homogênea às páginas que são versões de um mesmo documento. Os quatro escores propostos podem ser classificados em duas categorias: os que realizam mudanças estruturais no WebGraph (VersionRank e VersionPageRank) e os que realizam operações aritméticas sobre os escores obtidos pelo algoritmo de PageRank (VersionSumRank e VersionAverageRank). Os experimentos demonstram que o VersionRank tem desempenho 26,55% superior ao PageRank para consultas navegacionais sobre a WBR03 em termos de MRR, e em termos de P@10, o VersionRank tem um ganho de 9,84% para consultas informacionais da WBR99. Já o escore VersionAverageRank, apresentou melhores resultados na métrica P@10 para consultas informacionais na WBR99 e WBR03. Na WBR99, os ganhos foram de 6,74% sobre o PageRank. Na WBR03, para consultas informacionais aleatórias o escore VersionAverageRank obteve um ganho de 35,29% em relação ao PageRank. / Search engines use WebGraph formed by the pages and their links to assign reputation to Web pages. This reputation is used for ranking show for the user. However, new versions of pages with a good reputation distribute your votes of reputation among all versions, damaging the reputation of original page and also their versions. The objective of this work is to specify the new scores to consider all versions of a Web page to assign reputation to them. To achieve this goal, four scores were proposed using the version detection to assign a more homogeneous reputation to the pages that are versions of the same document. The four scores proposed can be classified into two categories: those who perform structural changes in WebGraph (VersionRank and VersionPageRank) and those who performs arithmetic operations on the scores obtained by the PageRank algorithm (VersionSumRank and VersionAverageRank). The experiments show that the performance VersionRank is 26.55% higher than the PageRank for navigational queries on WBR03 in terms of MRR, and in terms of P@10, the VersionRank has a gain of 9.84% for the WBR99 informational queries. The score VersionAverageRank showed better results in the metric P@10 for WBR99 and WBR03 information queries. In WBR99, it had a gain of 6.74% compared to PageRank. In WBR03 for random informational queries, VersionAverageRank showed an increase of 35.29% compared to PageRank.
148

A study of multiple attributes decision making methods facing uncertain attributes

Amini, Mohammadhossein January 1900 (has links)
Master of Science / Department of Industrial & Manufacturing Systems Engineering / Shing I. Chang / Many decision-making methods have been developed to help decision makers (DMs) make efficient decisions. One decision making method involves selecting the best choice among alternatives based on a set of criteria. Multiple Attribute Decision-Making (MADM) methods allow opportunities to determine the optimal alternative based on multiple attributes. This research aims to overcome two concerns in current MADM methods: uncertainty of attributes and sensitivity of ranking results. Based on availability of information for attributes, a DM maybe certain or uncertain on his judgment on alternatives. Researchers have introduced the use of linguistic terms or uncertain intervals to tackle the uncertainty problems. This study provides an integrated approach to model uncertainty in one of the most popular MADM methods: TOPSIS (Technique for Order Preference by Similarity to Ideal Solution). Current MADM methods also provide a final ranking of alternatives under consideration and, the final solution is based on a calculated number assigned to each alternative. Results have shown that the final value of alternatives may be close to each other uncertain attributes, but current methods rank alternatives according to the final scores. It exhibits a sensitivity issue related to formation of the ranking list. The proposed method solves this problem by simulating random numbers within uncertain intervals in the decision matrix. The proposed outcome is a ranking distribution for alternatives. The proposed method is based on TOPSIS, which defines the best and the worst solution for each attribute and defines the best alternative as closest to best and farthest from the worst solution. Random number distributions were studied under the proposed simulation solution approach. Result showed that triangular random number distribution provides better ranking results than uniform distribution. A case study of building design selection considering resiliency and sustainability attributes was presented to demonstrate use of the proposed method. The study demonstrated that proposed method can provide better decision option for designers due to the ability to consider uncertain attributes. In addition using the proposed method, a DM can observe the final ranking distribution resulted from uncertain attribute values.
149

Controversy Analysis: Clustering and Ranking Polarized Networks with Visualizations

January 2015 (has links)
abstract: US Senate is the venue of political debates where the federal bills are formed and voted. Senators show their support/opposition along the bills with their votes. This information makes it possible to extract the polarity of the senators. Similarly, blogosphere plays an increasingly important role as a forum for public debate. Authors display sentiment toward issues, organizations or people using a natural language. In this research, given a mixed set of senators/blogs debating on a set of political issues from opposing camps, I use signed bipartite graphs for modeling debates, and I propose an algorithm for partitioning both the opinion holders (senators or blogs) and the issues (bills or topics) comprising the debate into binary opposing camps. Simultaneously, my algorithm scales the entities on a univariate scale. Using this scale, a researcher can identify moderate and extreme senators/blogs within each camp, and polarizing versus unifying issues. Through performance evaluations I show that my proposed algorithm provides an effective solution to the problem, and performs much better than existing baseline algorithms adapted to solve this new problem. In my experiments, I used both real data from political blogosphere and US Congress records, as well as synthetic data which were obtained by varying polarization and degree distribution of the vertices of the graph to show the robustness of my algorithm. I also applied my algorithm on all the terms of the US Senate to the date for longitudinal analysis and developed a web based interactive user interface www.PartisanScale.com to visualize the analysis. US politics is most often polarized with respect to the left/right alignment of the entities. However, certain issues do not reflect the polarization due to political parties, but observe a split correlating to the demographics of the senators, or simply receive consensus. I propose a hierarchical clustering algorithm that identifies groups of bills that share the same polarization characteristics. I developed a web based interactive user interface www.ControversyAnalysis.com to visualize the clusters while providing a synopsis through distribution charts, word clouds, and heat maps. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2015
150

Multi-layered HITS on Multi-sourced Networks

January 2018 (has links)
abstract: Network mining has been attracting a lot of research attention because of the prevalence of networks. As the world is becoming increasingly connected and correlated, networks arising from inter-dependent application domains are often collected from different sources, forming the so-called multi-sourced networks. Examples of such multi-sourced networks include critical infrastructure networks, multi-platform social networks, cross-domain collaboration networks, and many more. Compared with single-sourced network, multi-sourced networks bear more complex structures and therefore could potentially contain more valuable information. This thesis proposes a multi-layered HITS (Hyperlink-Induced Topic Search) algorithm to perform the ranking task on multi-sourced networks. Specifically, each node in the network receives an authority score and a hub score for evaluating the value of the node itself and the value of its outgoing links respectively. Based on a recent multi-layered network model, which allows more flexible dependency structure across different sources (i.e., layers), the proposed algorithm leverages both within-layer smoothness and cross-layer consistency. This essentially allows nodes from different layers to be ranked accordingly. The multi-layered HITS is formulated as a regularized optimization problem with non-negative constraint and solved by an iterative update process. Extensive experimental evaluations demonstrate the effectiveness and explainability of the proposed algorithm. / Dissertation/Thesis / Masters Thesis Computer Science 2018

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