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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.
1

Purifica??o e performance da reutiliza??o do Magnesol usado na purifica??o de biodiesel como proposta de diminui??o dos custos do processo / Purification and performance of the reuse of Magnesol used in the biodiesel purification Process as a proposed decrease in the costs of the process

Coelho, Bruna Naidon 15 July 2016 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-09-26T12:25:36Z No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-09-26T12:25:44Z (GMT) No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) / Made available in DSpace on 2017-09-26T12:26:02Z (GMT). No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) Previous issue date: 2016-07-15 / New searches for technologies that allow to obtain fuels with the same efficiency of fossil fuels, however, with renewable raw material are increasingly on the agenda in the current world scenario. Biodiesel, derived from vegetable or animal oils, fits perfectly in this context, above all, biodiesel from frying oil that still brings to the surface the resolution of a major environmental problem: the incorrect disposal of oils that are harmful to the environment. However, in its transesterification, some undesirable by-products are found that can to cause problems in the automobile engine. For resolt this problem requires the purification of this biofuel. Purification can be obtented by two routes: wet and dry, the wet being most commonly used in industry. In this type of purification where the water is used for the washing of biodiesel, after purification, this contaminated water also entails another environmental problem: a highly polluted effluent. On the other hand, the dry purification makes use of an adsorbent that generates less effluent and, after use, is usually grounded by its users. In this work studed the recovery of an adsorbent that has been widely used, the Magnesol, and him reuse has been studied for cost reduction purposes in the biodiesel purification process. After the creation of the methodology of recuperation of Magnesol, some solvents were tested and, with the elemental analysis of Carbon, it was verified which solvent presented better performance in the adsorbent recovery, being THF the highlight of this work. The analysis of FTIR, TGA and MEV showed that the adsorbent recovery was efficient, and the chromatography analysis showed that the performance of biodiesel purification with recovered Magnesol should be more worked so that it can be more efficient as it is when used virgin. / Novas procuras por tecnologias que permitam obter-se combust?veis com a mesma efici?ncia dos combust?veis f?sseis, por?m, com mat?ria prima renov?vel est?o cada vez mais em pauta no cen?rio mundial. O biodiesel, proveniente de ?leos vegetais ou animais, encaixa-se perfeitamente neste contexto, sobretudo, o biodiesel proveniente de ?leo de fritura que ainda traz ? tona a resolu??o de um grande problema ambiental: o despejo incorreto de ?leos que s?o prejudiciais ao meio ambiente. Por?m, em sua transesterifica??o, s?o encontrados alguns subprodutos indesej?veis e que podem acarretar problemas no motor do autom?vel, sendo necess?ria a purifica??o deste biocombust?vel. A purifica??o pode ser realizada por duas vias: ?mida e seca, sendo a ?mida mais comumente utilizada na ind?stria. Neste tipo de purifica??o ? utilizado ?gua para a lavagem do biodiesel e, ap?s a purifica??o, esta ?gua contaminada tamb?m acarreta em outro problema ambiental: um efluente altamente polu?do. A purifica??o via seca faz a utiliza??o de um adsorvente que gera menos efluentes e, ap?s sua utiliza??o, costuma ser descartado em aterros sanit?rios pelos seus usu?rios. Neste trabalho foi estudado a recupera??o de um adsorvente que vem sendo muito utilizado, o Magnesol, bem como, sua reutiliza??o, para fins de redu??o de custos no processo de purifica??o do biodiesel. Ap?s a cria??o da metodologia de recupera??o do Magnesol, alguns solventes foram testados e, com a an?lise elementar de carbono, foi verificado qual solvente apresentou melhor performance na recupera??o do adsorvente, sendo THF o destaque deste trabalho. As an?lises de FTIR, TGA e MEV mostraram que a recupera??o do adsorvente foi eficiente, j? a an?lise de cromatografia gasosa mostrou que o desempenho da purifica??o do biodiesel com Magnesol recuperado dever? ser mais trabalhada para que o mesmo possa ser mais eficiente tal qual quando utilizado ainda virgem.
2

Respostas ? aduba??o mineral e org?nica e faixas adequadas de atributos qu?micos de rejeito de minera??o de quartzito para duas esp?cies nativas / Responses to mineral and organic fertilization and appropriate ranges of chemical attributes of reject mining quartzite for two native species

Gon?alves, Neubert Homem 26 February 2014 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:21:18Z No. of bitstreams: 2 neubert_homem_goncalves.pdf: 444697 bytes, checksum: 5d20dc726c6a0961a5d4b09ee7e4ebea (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:22:50Z (GMT) No. of bitstreams: 2 neubert_homem_goncalves.pdf: 444697 bytes, checksum: 5d20dc726c6a0961a5d4b09ee7e4ebea (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:22:41Z (GMT) No. of bitstreams: 2 neubert_homem_goncalves.pdf: 444697 bytes, checksum: 5d20dc726c6a0961a5d4b09ee7e4ebea (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T18:23:20Z (GMT) No. of bitstreams: 2 neubert_homem_goncalves.pdf: 444697 bytes, checksum: 5d20dc726c6a0961a5d4b09ee7e4ebea (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-01-05T18:23:20Z (GMT). No. of bitstreams: 2 neubert_homem_goncalves.pdf: 444697 bytes, checksum: 5d20dc726c6a0961a5d4b09ee7e4ebea (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O decl?nio da minera??o de diamante em Diamantina (MG) e entorno, com a interrup??o das descobertas e o gradativo esgotamento das minas em opera??o est? levando a descoberta e a explora??o de maci?os de quartzito havendo a degrada??o da vegeta??o existente, e do solo, criando um ambiente bastante in?spito ao crescimento de plantas. Este trabalho objetivou avaliar o comportamento e as faixas adequadas ao crescimento inicial de Eremanthus erythropappus e Solanum lycocarpum, ap?s a influ?ncia da aduba??o mineral e org?nica quando cultivada em rejeito da minera??o de quartzito. O experimento foi conduzido em casa de vegeta??o, sendo os tratamentos dispostos no formato de delineamento inteiramente casualizado, com cinco combina??es de aduba??o mineral (AM) e org?nica (AO) e um tratamento adicional do rejeito sem AM e AO (Controle), com quatro repeti??es. As combina??es consistiram de 100% AM - 0% AO; 75% AM - 25% AO; 50% AM - 50% AO; 25% AM - 75% AO; 0% AM - 100% AO, sendo as doses de 150 mg de N, 140 mg de P, 150 mg de K e 5 g de esterco de curral por dm? de rejeito de quartzito correspondente a 100% AM e 100% AO. As demais doses foram proporcionais ?s combina??es dos tratamentos. Foram avaliados os par?metros de crescimento para cada uma das esp?cies, sendo estes, di?metro do coleto, altura de mudas, massa seca da parte a?rea (MSPA), de ra?zes (MSR) e rela??o MSR/MSPA. Atrav?s das combina??es adequadas de aduba??o, os maiores resultados apresentados pela candeia com rela??o ?s vari?veis avaliadas, foram na dose com 50% AM - 50% AO, correspondente a 75 mg de N, 70 mg de P, 75 mg de K e 2,5 g de esterco de curral; enquanto que para a lobeira, os maiores resultados ocorreram na dose de 25% AM - 75% AO, correspondente a 37,5 mg de N, 35 mg de P, 37,5 mg de K e 3,75 g de esterco de curral por dm? de rejeito de quartzito. As doses recomendadas para o crescimento inicial (90% produ??o m?xima da MSPA) da candeia foram 66,5 mg de N; 62,0 mg de P, 66,5 mg de K e 2,8 g de esterco de curral por dm3 de rejeito quartzito. Para a lobeira, as doses recomendadas foram 55,5 mg de N; 51,8 mg de P, 55,5 mg de K e 2,3 g de esterco de curral por dm3 de rejeito de quartzito. Foram definidas faixas adequadas dos atributos qu?micos de rejeito de minera??o quartzito para as duas esp?cies nativas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT The decline in diamond mining in Diamantina (MG) and its surroundings, with the interruption of the findings and the gradual exhaustion of operating mines is leading the discovery and exploitation of massive quartzite going degradation of existing vegetation, and soil, creating an environment very inhospitable to plant growth. This work aimed to evaluate the behavior and appropriate range to the initial growth of Eremanthus erythropappus and Solanum lycocarpum after the influence of mineral and organic when grown in reject from mining of quartzite fertilization. The experiment was conducted in a greenhouse, with treatments arranged in a completely randomized design, with five combinations of mineral fertilizer (MF) and organic (OF) and an additional treatment of the reject without AM and AO (Control), with four replications. Combinations consisted of 100% MF - 0% OF; 75% MF - 25% OF; 50% MF - 50% OF; 25% MF - 75% OF; 0% MF - 100% OF, with doses of 150 mg of N, 140 mg of P, 150 mg of K and 5 g of bovine manure for dm? of reject quartzite corresponding to 100% MF and 100% OF. The remaining doses were proportional to the combinations of treatments. Parameters of growth for each species, these being, diameter, height of seedling, mass weight of shoot (MWS), root (MSR) and ratio MWR/MSPA were evaluated. Through appropriate fertilizer combinations, the greatest results presented by the Eremanthus erythropappus with respect to the variables evaluated, in dose were 50% MF - 50% OF, corresponding to 75 mg of N, 70 mg of P, 75 mg of K and 2,5 g of bovine manure; while for Solanum lycocarpum, the greatest results occurred in a dose of 25% MF - 75% OF, corresponding to 37,5 mg of N, 35 mg of P, 37,5 mg of K and 3,75 g of bovine manure for dm? of reject quartzite. The recommended doses for the initial growth (90% maximum production MWS) of the Eremanthus erythropappus were 66,5 mg of N; 62,0 mg of P, 66,5 mg of K and 2,8 g of bovine manure for dm? of reject quartzite. For Solanum lycocarpum, the recommended doses were 55,5 mg of N; 51,8 mg of P, 55,5 mg of K and 2,3 g of bovine manure for dm? of reject quartzite. The appropriate range of chemical attributes of reject quartzite mining for the two native species were defined.
3

Um modelo matem?tico baseado em wavelets para an?lise do m?todo t?rmico de recupera??o de ?leo pesado aplicando irradia??o eletromagn?tica

Santos, Mois?s Dantas dos 24 November 2010 (has links)
Made available in DSpace on 2014-12-17T14:09:11Z (GMT). No. of bitstreams: 1 MoisesDS_TESE.pdf: 1070029 bytes, checksum: 7b8c0e14f4004a23381cacf6ed8c03a2 (MD5) Previous issue date: 2010-11-24 / This work proposes a model to investigate the use of a cylindrical antenna used in the thermal method of recovering through electromagnetic radiation of high-viscosity oil. The antenna has a simple geometry, adapted dipole type, and it can be modelled by using Maxwell s equation. The wavelet transforms are used as basis functions and applied in conjunction with the method of moments to obtain the current distribution in the antenna. The electric field, power and temperature distribution are carefully calculated for the analysis of the antenna as electromagnetic heating. The energy performance is analyzed based on thermo-fluid dynamic simulations at field scale, and through the adaptation in the Steam Thermal and Advanced Processes Reservoir Simulator (STARS) by Computer Modelling Group (CMG). The model proposed and the numerical results obtained are stable and presented good agreement with the results reported in the specialized literature / Neste trabalho ? proposto um modelo para investigar o uso de uma antena cil?ndrica utilizada no m?todo t?rmico de recupera??o por irradia??o eletromagn?tica de petr?leo de alta viscosidade. A antena apresenta uma geometria simples, do tipo dipolo adaptada, e pode ser modelada usando-se as equa??es de Maxwell. As transformadas de wavelets s?o usadas como fun??es de base e aplicadas em conjunto com o m?todo dos momentos na obten??o da distribui??o de corrente na antena. O campo el?trico, a distribui??o de energia e a temperatura s?o cuidadosamente calculadas para analise da antena como aquecedor eletromagn?tico. O desempenho energ?tico ? analisado a partir de simula??es termo-fluidodin?micas em escala de campo, atrav?s da adapta??o no Steam Thermal and Advanced Processes Reservoir Simulator (STARS) da empresa de software Computer Modelling Group (CMG). Os resultados obtidos para po?os constitu?dos por ?leos viscosos s?o est?veis e apresentam boa concord?ncia com resultados da literatura
4

Paisagismo produtivo na prote??o e recupera??o de fundos de vale urbanos / Productive landscape in protection and recovery of the bottom of urban valleys

Nahum, Noemie Nelly 14 February 2007 (has links)
Made available in DSpace on 2016-04-04T18:21:39Z (GMT). No. of bitstreams: 1 Noemie Nelly.pdf: 4915176 bytes, checksum: 08b96c7e3d131217a91c33facc7c7200 (MD5) Previous issue date: 2007-02-14 / The search for alternatives for environmental protection and recovery with special focus on water, in its original site, has been the theme of debate in diverse areas of knowledge under different points of view. This study, inserted in the realm of productive landscape, analyses the risks and advantages of growing fruit trees for the protection and recovery of the bottom of urban valleys. This questioning has been done by the analysis of technical works that approach correlated subjects and from results of carried through interviews with professionals in diverse areas of knowledge. In these interviews professionals had been requested to present their interpretations according to the possibilities and limitations of the adoption of techniques of productive landscape, as and strategy to protect and recovery of lands located on the border of the urban s waters. It has as general objective, to contribute for the improvement of the water quality and the environment conditions of the water s courses insert into urban mesh, and, as an specific objective, contribute for the formulation of landscape s projects a of protection and recovery of urban hydrographic basis where are foreseen the landscapes qualifications of the lands in the bottom of valleys. / A busca de alternativas para a prote??o e recupera??o dos bens naturais, em especial, a ?gua em seu local de origem, tem sido tem?tica de discuss?o sob diferentes enfoques, nas diversas ?reas de conhecimento. Neste estudo, que se insere na tem?tica do Paisagismo Produtivo, questiona-se a respeito de riscos e vantagens no plantio de esp?cies frut?feras na prote??o e recupera??o de fundos de vale urbanos. Esse questionamento foi feito a partir da an?lise de trabalhos t?cnicos que abordam temas correlatos e a partir dos resultados de entrevistas realizadas com profissionais de diversas ?reas de conhecimento. Nestas entrevistas, os profissionais foram solicitados a apresentar suas interpreta??es quanto ?s possibilidades e limita??es da ado??o de t?cnicas de paisagismo produtivo, como estrat?gia para prote??o e recupera??o dos terrenos situados junto aos corpos de ?gua urbanos. Tem-se, como objetivo geral, contribuir para a melhoria da qualidade da ?gua e das condi??es ambientais dos cursos de ?gua inseridos no tecido urbano e, como objetivo espec?fico, contribuir para a formula??o de projetos de prote??o e recupera??o de microbacias hidrogr?ficas urbanas, em que est?o previstos as qualifica??es paisag?sticas dos terrenos de fundo de vale.
5

Recomenda??o de tags para m?dia social colaborativa: da generaliza??o ? personaliza??o

Ziesemer, Angelina de Carvalho A. 20 March 2012 (has links)
Made available in DSpace on 2015-04-14T14:49:47Z (GMT). No. of bitstreams: 1 438773.pdf: 3581155 bytes, checksum: 8bd17c869fd04adc206bbbcd32f4b1dd (MD5) Previous issue date: 2012-03-20 / Social media systems such as Flickr, Youtube and Picasa have become very popular as they provide a collaborative environment to share photos and videos supporting tags, ratings and comments. This kind of interaction includes a lot of content provided by users, which may bring meaningful information to recommendation systems. The aggregation of tags is also a way to cluster items and provide tag-based search content. We investigate how to support tag recommendation by ranking the co-occurrence, popularity and relevance of commonly-used tags in similar items and by similar users. We developed a tag recommendation system to recommend of possibly relevant tags. We use Flickr s dataset to analyze our algorithm s behavior and present the results provide by the experiment. A new model using personalized recommendation was developed using the experiment results and the behavior of each user. / Sistemas de m?dia social como Flickr, Youtube e Picasa tornaram-se muito populares devido ao seu ambiente para compartilhamento de imagens, v?deos e suporte ? atribui??o de tags, avalia??es e coment?rios. Sistemas colaborativos possuem grandes quantidades de conte?do provido pelos usu?rios, os quais fornecem informa??es relevantes para engines de recomenda??o. O uso de tags tamb?m permite a clusteriza??o e busca de conte?do baseado em palavras-chaves. Neste trabalho foi investigado um mecanismo para recomendar tags, desenvolvendo medidas de co-ocorr?ncia, popularidade e relev?ncia de tags comumente usadas em itens similares e por usu?rios similares. Foi desenvolvido um sistema para recomendar poss?veis tags relevantes baseadas na similaridade contextual de outras tags providas pelos usu?rios. Para o desenvolvimento do experimento, foi utilizado um dataset do Flickr para gerar recomenda??es e analisar o comportamento do algoritmo e as atribui??es efetuadas pelos usu?rios participantes. Os resultados obtidos demonstraram padr?es de atribui??o e desempenho de acordo com o conte?do/contexto da imagem. Utilizando a frequ?ncia de atribui??o baseada no hist?rico de cada perfil ? sugerido um novo modelo personalizado para recomenda??o de tags.
6

Extra??o autom?tica de conceitos a partir de textos em l?ngua portuguesa

Lopes, Lucelene 26 January 2012 (has links)
Made available in DSpace on 2015-04-14T14:49:48Z (GMT). No. of bitstreams: 1 439085.pdf: 7508888 bytes, checksum: c69f67a5ec361212f83a17a4407866ce (MD5) Previous issue date: 2012-01-26 / This thesis describes a process to extract concepts from texts in portuguese language. The proposed process starts with linguistic annotated corpora from specific domains, and it generates lists of concepts for each corpus. The proposal of a linguistic oriented extraction procedure based on noun phrase detection, and a set of heuristics to improve the overall quality of concept candidate extraction is made. The improvement in precision and recall of extracted term list is from approximatively from 10% to more more than 60%. A new index (tf-dcf) based on contrastive corpora is proposed to sort the concept candidate terms according to the their relevance to their respective domain. The precision results achieved by this new index are superior to to the results achieved by indices proposed in similar works. Cut-off points are proposed in order to identify, among extracted concept candidate terms sorted according to their relevance, which of them will be considered concepts. A hybrid approach to choose cut-off points delivers reasonable F-measure values, and it brings quality to the concept identification process. Additionally, four applications are proposed in order to facilitate the comprehension, handling, and visualization of extracted terms and concepts. Such applications enlarge this thesis contributions available to a broader community of researchers and users of Natural Language Processing area. The proposed process is described in detail, and experiments empirically evaluate each process step. Besides the scientific contribution made with the process proposal, this thesis also delivers extracted concept lists for five different domain corpora, and the prototype of a software tool (EχATOLP) implementing all steps of the proposed process. / Essa tese descreve um processo para extrair conceitos de textos em l?ngua portuguesa. O processo proposto inicia com corpora de dom?nio linguisticamente anotados, e gera listas de conceitos dos dom?nios de cada corpus. Utiliza-se uma abordagem lingu?stica, que baseia-se na identifica??o de sintagmas nominais e um conjunto de heur?sticas que melhoram a qualidade da extra??o de candidatos a conceitos. Essa melhora ? expressa por incrementos aproximadamente de 10% para mais de 60% nos valores de precis?o e abrang?ncia das listas de termos extra?das. Prop?e-se um novo ?ndice (tf-dcf) baseado na compara??o com corpora contrastantes, para ordenar os termos candidatos a conceito extra?dos de acordo com suas relev?ncias para o corpus de dom?nio. Os resultados obtidos com esse novo ?ndice s?o superiores aos resultados obtidos com ?ndices propostos em trabalhos similares. Aplicam-se pontos de corte para identificar, dentre os termos candidatos classificados segundo sua relev?ncia, quais ser?o considerados conceitos. O uso de uma abordagem h?brida para escolha de pontos de corte fornece valores adequados de medida F, trazendo qualidade ao processo de identifica??o de conceitos. Adicionalmente. prop?em-se quatro aplica??es para facilitar a compreens?o, manipula??o e visualiza??o dos termos e conceitos extra?dos. Essas aplica??es tornam as contribui??es dessa tese acess?veis a um maior n?mero de pesquisadores e usu?rios da ?rea de Processamento de Linguagem Natural. Todo o processo proposto ? descrito em detalhe, e experimentos avaliam empiricamente cada passo. Al?m das contribui??es cient?ficas feitas com a proposta do processo, essa tese tamb?m apresenta listas de conceitos extra?dos para cinco diferentes corpora de dom?nio, e o prot?tipo de numa ferramenta de software (EXATOLP) que implementa todos os passos propostos.
7

Um modelo para a an?lise de impacto em c?digo fonte usando ontologias e recupera??o de informa??o

Noll, Rodrigo Perozzo 13 August 2012 (has links)
Made available in DSpace on 2015-04-14T14:49:53Z (GMT). No. of bitstreams: 1 442552.pdf: 9370705 bytes, checksum: 8a3aef50bd6e373e63349d63858be524 (MD5) Previous issue date: 2012-08-13 / Changes are inevitable during the product lifecycle. These changes are due different needs, such as the knowledge evolution of business processes, environment or infrastructure changes, etc. Under these circumstances, it is crucial to have the control about the knowledge of what these changes mean to the system. Impact analysis represents the process that creates this knowledge. The impact analysis has a wide meaning for software development, such as the assessment of source code structures or the control of project management constraints. This thesis aims to present a model to analyze the impact in source code using ontologies in order to improve precision and recall of the identified source code structures compared to existing techniques. The use of ontologies integrates a semantic layer under the traditional techniques founded in syntactic analysis. To develop the impact analysis model, it was defined two different sub models: traceability and probability. The traceability model receives as input the source code and domain ontology and generates a traceability ontology populated with links between domain concepts (classes and properties) and source code units (classes, methods and attributes). These links are populated by a lexical and semantic analyzer that categorize, normalize (token generation, expansion and elimination) and compare (stemming) each token. With the traceability ontology and a change request, the probabilistic model classifies each traceability link using Bayesian Belief Networks. To the probability calculus, the node classification used the Google PageRank algorithm and the arrows used frequency analysis TFIDF and conceptual dependency, defined in this thesis. The impact analysis model was implemented as an Eclipse plugin and was empirically evaluated using three controlled experiments. / Mudan?as s?o inevit?veis durante o ciclo de vida do software. Estas mudan?as s?o resultado de diferentes necessidades, como a evolu??o do conhecimento sobre os processos de neg?cio, altera??es de ambiente, etc. Nestas circunst?ncias, ? crucial ter controle sobre o que essas mudan?as representam na aplica??o. A an?lise de impacto representa o processo que gera este conhecimento. Essa an?lise possui um significado abrangente dentro do desenvolvimento de software, incluindo desde a identifica??o de estruturas no c?digo fonte at? o controle das restri??es de gest?o de projeto. Esta tese apresenta um modelo para analisar o impacto no c?digo fonte de uma aplica??o utilizando ontologias, visando melhorar a precis?o e revoca??o de estruturas identificadas se comparadas a t?cnicas existentes. O uso de ontologias integra uma perspectiva sem?ntica nas t?cnicas tradicionalmente baseadas na an?lise sint?tica do c?digo fonte. Para o desenvolvimento do modelo de an?lise de impacto, foram definidos dois submodelos: o de rastreabilidade e o de probabilidade. O modelo de rastreabilidade recebe como entrada o c?digo fonte e uma ontologia de dom?nio e gera como resultado uma ontologia de rastreabilidade populada automaticamente com elos entre conceitos do dom?nio (classes e propriedades) e estruturas do c?digo (classes, m?todos e atributos). Estes elos s?o populados atrav?s de um analisador l?xico e sem?ntico que realiza a categoriza??o, normaliza??o (gera??o de tokens, expans?o e elimina??o) e compara??o (stemming). Com base na ontologia de rastreabilidade e em um requisito de mudan?a, o modelo probabil?stico classifica cada elo de rastreabilidade utilizando o modelo de Redes de Cren?as Bayesianas. Para o c?lculo de probabilidade, a classifica??o dos nodos utilizou o algoritmo PageRank do Google e das arestas, a an?lise de frequ?ncia TFIDF e a depend?ncia conceitual, definida nesta tese. Este modelo de an?lise de impacto foi implementado como um plugin do eclipse e foi avaliado empiricamente atrav?s de tr?s experimentos controlados.
8

Minera??o de opini?es aplicada a m?dias sociais

Souza, Marlo Vieira dos Santos e 19 March 2012 (has links)
Made available in DSpace on 2015-04-14T14:50:01Z (GMT). No. of bitstreams: 1 448645.pdf: 990116 bytes, checksum: 3ad832cb853385fcbb55975315370396 (MD5) Previous issue date: 2012-03-19 / The competitive environment has become more dynamic in the last few decades due to the great development of information and comunication technologies and to the globalization process.A company manager must, thus, always be well informed about the competitive landscape before making strategic decisions. In this sense, the Competitive Intelligence (CI) emerges as a discipline that aims to systematize the collection and analysis of information in the competitive environment willing to assist decision making. There is, however, an increasing amount of information being produced and released in Internet and traditional media, which become unwieldy. Associated with this, managers still suffer with time constraints to respond to the market stimuli and remain competitive. Thus, it is necessary to maintain a constant staff monitoring the competitive environment to be able to handle the amount of information from this various sources. We believe that the application Text Analysis techniques can help in various stages of such process. This work presents a proposal to use such techniques to aid the process of Competitive Intelligence. We discuss the use of Sentiment Analysis techniques coupled with Named Entity Recognition in texts from social media - especially Twitter - which helps in the analysis of the attitudes of the consumer market towards a brand. We also present a system implementing the proposed techniques, the evaluations made with it and present our conclusions. / O ambiente competitivo se tornou, nas ultimas d?cadas, mais din?mico gra?as ?s tecnologias de informa??o e comunica??o e ? globaliza??o. O gestor, assim, precisa estar sempre bem informado sobre o panorama competitivo antes de tomar decis?es estrat?gicas. Nessa dire??o, a Intelig?ncia Competitiva (IC) surge como uma disciplina que pretende sistematizar a obten??o e an?lise de informa??es do ambiente competitivo com fun??o de auxiliar a tomada de decis?o. H? entretanto uma quantidade crescente de informa??o sendo produzida e disponibilizada em meios como a Internet e m?dias tradicionais, as quais se tornam de dif?cil manejo. Associado a isso, os gestores sofrem ainda com restri??es temporais para responder ao est?mulo do mercado e manteremse competitivos. Dessa forma, ? necess?rio manter uma equipe de monitoramento constante do ambiente competitivo para que se possa lidar com a quantidade de informa??o proveniente de diversas fontes. Acreditamos que a aplica??o de t?cnicas de An?lise de Texto podem auxiliar nas diversas fases do processo de IC. O presente trabalho apresenta uma proposta de utiliza??o de tais t?cnicas para auxiliar o processo de Intelig?ncia Competitiva. Discutimos aqui a utiliza??o de um m?todo de An?lise de Sentimentos aliado ao Reconhecimento de Entidades Nomeadas em textos provenientes de m?dias sociais - particularmente o Twitter - que permitam analisar as atitudes do mercado consumidor quanto a uma determinada marca. S?o apresentados ainda o sistema desenvolvido, as avalia??es realizadas e as conclus?es que tiramos.
9

Extra??o de rela??es do dom?nio de organiza??es para o portugu?s

Abreu, Sandra Collovini de 16 January 2014 (has links)
Made available in DSpace on 2015-04-14T14:50:10Z (GMT). No. of bitstreams: 1 457562.pdf: 2425407 bytes, checksum: fefac4edf439614aa48e880ee5b36971 (MD5) Previous issue date: 2014-01-16 / The task of Relation Extraction from texts is one of the main challenges in the area of Information Extraction, considering the required linguistic knowledge and the sophistication of the language processing techniques employed. This task aims at identifying and classifying semantic relations that occur between entities recognized in a given text. For example, the sentence Next Saturday, Ronaldo Lemos, director of Creative Commons, will participate in a debate [...]" expresses a institutionalbond" relation that occurs between the named entities Ronaldo Lemos" and Creative Commons". This thesis proposes a process for extraction of relation descriptors, which describes the explicit relations between named entities in the Organization domain (Person, Organization and Location) by applying, to texts in Portuguese, Conditional Random Fields (CRF), a probabilistic model that has been used in various tasks e⇥ciently in processing sequential text, including the task of Relation Extraction. In order to implement the proposed process, a reference corpus for extracting relations, necessary for learning, was manually annotated based on a reference corpus for named entities (HAREM). Based on an extensive literature review on the automatic extraction of relations task, features of different types were defined. An experimental evaluation was performed to evaluate the learned model utilizing the defined features. Different input feature configurations for CRF were evaluated. Among them, the highlight was the inclusion of the semantic feature based on the named entity category, since this feature could express, in a better way, the kind of relationship between the pair of named entities we want to identify. Finally, the best results correspond to the extraction of relations between the named entities of Organization and Person categories, in which the F -measure rates were 57% and 63%, considering the correct and partially correct extractions, respectively. / A tarefa de Extra??o de Rela??es a partir de textos ? um dos principais desafios da ?rea de Extra??o de Informa??o, tendo em vista o conhecimento lingu?stico exigido e a sofistica??o das t?cnicas de processamento da l?ngua empregados. Essa tarefa visa identificar e classificar rela??es sem?nticas que ocorrem entre entidades reconhecidas em um determinado texto. Por exemplo, o trecho No pr?ximo S?bado, Ronaldo Lemos, diretor da Creative Commons, ir? participar de um debate (...)" expressa uma rela??o de v?nculo-institucional" que ocorre entre as entidades nomeadas Ronaldo Lemos" e Creative Commons". Esta tese prop?e um processo para extra??o de descritores de rela??o, os quais descrevem rela??es expl?citas entre entidades nomeadas do dom?nio de Organiza??es (Pessoa, Organiza??o e Local) utilizando o modelo probabil?stico Conditional Random Fields (CRF), e sua aplica??o em textos da L?ngua Portuguesa. O modelo probabil?stico CRF tem sido aplicado eficientemente em diversas tarefas de processamento de texto sequencial, incluindo recentemente a tarefa de Extra??o de Rela??es. A fim de aplicar o processo proposto, um corpus de refer?ncia para extra??o de rela??es, necess?rio para o aprendizado, foi anotado manualmente, tomando como base um corpus de refer?ncia para entidades nomeadas (HAREM). Com base em uma extensa revis?o da literatura sobre a tarefa de extra??o autom?tica de rela??es, features de diferentes naturezas foram definidas. Uma avalia??o experimental foi realizada com o objetivo de avaliar o modelo aprendido utilizando as features definidas. Diferentes configura??es de features de entrada para o CRF foram avaliadas. Dentre elas, destacou-se a inclus?o da feature sem?ntica baseada na categoria da entidade nomeada, j? que essa feature conseguiu expressar melhor o tipo de rela??o que se deseja identificar entre o par de entidades nomeadas. Por fim, os melhores resultados obtidos correspondem ? extra??o de rela??es entre as entidades nomeadas das categorias Organiza??o e Pessoa, na qual as taxas de F-measure foram de 57% e 63%, considerando as extra??es corretas e parcialmente corretas, respectivamente.
10

A proposal for an architecture to extract information from sms messages during emergency situations

Monteiro, Douglas Machado 16 March 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-15T11:49:34Z No. of bitstreams: 1 468523 - Texto Completo.pdf: 3578868 bytes, checksum: 4d26c3b12a22330579e4b83f7414ebc4 (MD5) / Made available in DSpace on 2015-05-15T11:49:34Z (GMT). No. of bitstreams: 1 468523 - Texto Completo.pdf: 3578868 bytes, checksum: 4d26c3b12a22330579e4b83f7414ebc4 (MD5) Previous issue date: 2015-03-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In mass emergencies, a fair amount of information is exchanged via SMS messages. These messages tend to be informal and to contain abbreviations and misspellings, which makes them difficult to treat. This is a problem for current Information Extraction tools, especially for messages in Portuguese. This work proposes an architecture to extract information from SMS messages during emergencies. The architecture comprises four components: Linguistic Processing, Temporal Processing, Event Processing, and Information Fusion. We also defined an SMS corpus building process. From the proposal of this architecture, we conducted a case study, which included building BraCorpSMS, a corpus of SMS messages received by an electric utility company. We built a prototype in Python using NLTK to validate the architecture. The prototype had its Information Extraction components evaluated achieving Precision of 88%, Recall of 59% and balanced F-measure of 71%. The results indicate improvement opportunities, but as this is the first work for Portuguese facing processing SMS messages during emergency situations, it also serves as a roadmap for future work in the area. / Durante situa??es de emerg?ncia, uma grande quantidade de informa??o ? trocada via mensagens SMS. Estas mensagens costumam ter escrita informal e cont?m abrevia??es e erros de grafia, o que dificulta seu processamento. Este ? um problema para as ferramentas de Extra??o de Informa??o atuais, especialmente para o Portugu?s. Este trabalho prop?e uma arquitetura de extra??o de informa??o de mensagens SMS em situa??es de emerg?ncia. A arquitetura contempla quatro componentes: processamento lingu?stico, processamento temporal, processamento de eventos e fus?o da informa??o. Tamb?m se define um processo para cria??o de corpus de SMSs. A partir da arquitetura proposta, foi realizado um estudo de caso que incluiu a constru??o do BraCorpSMS, um corpus de mensagens SMS recebidos por uma companhia de energia el?trica e um prot?tipo em Python utilizando NLTK para validar a arquitetura. O prot?tipo teve seus componentes de Extra??o de Informa??o avaliados, obtendo 88% de Precis?o, 59% de Cobertura e 71% de Medida-F. Os resultados indicam oportunidades de avan?os, mas, sendo este o primeiro trabalho para o Portugu?s voltado para o processamento de mensagens SMS em situa??es de emerg?ncia, tamb?m serve de roteiro para trabalhos futuros nesta ?rea.

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