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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.
341

Heurísticas para aprimorar o método BMW e suas variantes

Carvalho, Lídia Lizziane Serejo de 11 March 2015 (has links)
Submitted by Kamila Costa (kamilavasconceloscosta@gmail.com) on 2015-06-11T19:18:34Z No. of bitstreams: 1 Dissertação-Lídia L S de Carvalho.pdf: 837456 bytes, checksum: 620d89f05fc84dc2af7b89b6b6e587a0 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-15T17:53:19Z (GMT) No. of bitstreams: 1 Dissertação-Lídia L S de Carvalho.pdf: 837456 bytes, checksum: 620d89f05fc84dc2af7b89b6b6e587a0 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-15T17:57:19Z (GMT) No. of bitstreams: 1 Dissertação-Lídia L S de Carvalho.pdf: 837456 bytes, checksum: 620d89f05fc84dc2af7b89b6b6e587a0 (MD5) / Made available in DSpace on 2015-06-15T17:57:19Z (GMT). No. of bitstreams: 1 Dissertação-Lídia L S de Carvalho.pdf: 837456 bytes, checksum: 620d89f05fc84dc2af7b89b6b6e587a0 (MD5) Previous issue date: 2015-03-11 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Several research efforts have been conducted in the literature to develop methods to reduce the cost of query processing in search engines. This research aims to propose modifications to improve the performance of the block-Max WAND (BMW) algorithm, one of the most efficient algorithms proposed previously. The BMW algorithm uses heuristics to discard the documents entries at query processing, which makes it extremely fast. In this dissertation, we propose and evaluate additional heuristics to improve the perfomance of BMW and your variant BMW-CS in an attempt to both further reduces query processing times and the amount of memory required for processing queries. / Nos últimos anos, pesquisas relacionadas ao processamento de consultas em máquinas de busca têm sido realizadas com o objetivo de desenvolver métodos que reduzam o seu custo. Este trabalho visa propor modificações para melhorar o desempenho do algoritmo Block-Max WAND (BMW), um dos algoritmos mais eficientes propostos na literatura. O algoritmo BMW utiliza heurísticas para descartar documentos da resposta durante o processamento de consultas, o que torna sua execução extremamente veloz. Nesta dissertação, serão propostas e experimentadas modificações nas heurísticas de descarte de documentos e redução na quantidade de memória utilizada para processar consultas pelo algoritmo BMW e suas variantes, buscando-se assim ganhos de desempenho.
342

Detecção de regiões de massa por análise bilateral adaptada à densidade da mama utilizando índices de similaridade e redes neurais convolucionais / Detection of Mass Regions by Bilateral Analysis Adapted to Breast Density using Similarity and Convolutional Neural Networks

Diniz , João Otávio Bandeira 03 February 2017 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-05-30T21:09:57Z No. of bitstreams: 1 JoaoDiniz.pdf: 2606559 bytes, checksum: 262a9c98db11667d3a482c378ab78b50 (MD5) / Made available in DSpace on 2017-05-30T21:09:57Z (GMT). No. of bitstreams: 1 JoaoDiniz.pdf: 2606559 bytes, checksum: 262a9c98db11667d3a482c378ab78b50 (MD5) Previous issue date: 2017-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Breast cancer is the type of cancer that most affects women and is one of the leading causes of death worldwide. Aiming to aid the detection and diagnosis of this pathology, several techniques in the image area are being created serving as a second opinion. It is known that mammograms of the left and right breast present a high degree of symmetry, and when there is a sudden difference between the pairs, it can be considered suspicious. It is also emphasized that the breast can present different density of the tissue and this can be a factor that makes difficult the detection and diagnosis of the lesions. Thus, the objective of this work is to develop an automatic methodology for the detection of mass regions in pairs of digitized mammograms adapted to breast density, using image processing and species comparison techniques to determine asymmetric regions in the breasts together with neural convolutional networks for Classification of breast density and regions in masses and not masses. The proposed methodology is divided into two phases: training phase and test phase. In the training phase will be created three models using convolutional neural networks, the first able to classify the breast as density and the last two to classify regions of mass and non-mass in dense and non-dense breasts.The steps are in aligning the breasts so that it is possible to make a comparison between the pairs. When comparing, asymmetric regions will be segmented, these regions will undergo a process of reduction of false positives in order to eliminate regions that are not masses. Before classifying the remaining regions, the breasts undergo the process of density classification by the model obtained in the training phase. Finally, for each type of breast, a model will classify the regions segmented into masses and not masses. The methodology presented excellent results, in the non-dense breasts reaching sensitivity of 91.56 %, specificity of 90.73 %, accuracy of 91.04 % and rate of 0.058 false positives per image. Dense breasts showed 90.36 % sensitivity, 96.35 % specificity, 94.84 % accuracy and 0.027 false positives per image. The results show that the methodology is promising and can be used to compose a CAD system, serving as a second option for the expert in the task of detecting mass regions. / O cãncer de mama é o tipo de câncer que mais acomete as mulheres e uma das principais causas de morte em todo o mundo. Visando auxiliar a detecção e diagnóstico desta patologia, diversas técnicas na érea de imagem estão sendo criadas servindo como um auxílio ao especialista. Sabe-se que mamografias esquerda e direita apresentam alto grau simetria, e quanto há uma diferença brusca entre os pares, pode-se considerar algo de suspeito. Ressalta-se também que a mama pode apresentar densidade diferente do tecido e isso pode ser um fator que dificulte na detecção e diagnóstico das lesões. Assim, o objetivo deste trabalho é desenvolver uma metodologia automática de detecção de regiões de massa em pares de mamografias digitalizadas adaptada à densidade da mama, utilizando técnicas de processamento de imagens e comparação de espécies para determinar regiões assimétricas nas mamas juntamente com redes neurais convolucionais para classificação de densidade da mama e de regiões em massas e não massas. A metodologia proposta é dividida em duas fases: fase de treinamento e fase de teste. Na fase de treinamento serão criados três modelos utilizando redes neurais convolucionais, o primeiro capaz de classificar a mama quanto a densidade e os dois últimos classificam regiões de massa e não massa em mamas densas e não densas. Na fase de teste, imagens de mamografia da base DDSM passarão por várias etapas a fim de segmentar regiões assimétricas que serão posteriormente classificadas. As etapas resumem-se em alinhar as mamas para que seja possível fazer uma comparação entre os pares. Ao comparar, serão segmentadas regiões assimétricas, essas regiões passarão por processo de redução de falsos positivos a fim de eliminar regiões que não são massas. Antes de classificar as regiões restantes, as mamas passam pelo processo de classificação de densidade pelo modelo obtido na fase de treinamento. Por fim, para cada tipo de mama, um modelo irá classificar as regiões segmentadas em massas e não massas. O método proposto apresentou resultados promissores, nas mamas não densas atingiu sensibilidade de 91,56%, especificidade de 90,73%, 91,04% de acurácia e taxa de 0,058 falsos positivos por imagem. As mamas densas, apresentaram resultados de 90,36% de sensibilidade, 96,35% de especificidade, 94,84% de acurácia e 0,027 falsos positivos por imagem. Os resultados mostram que a metodologia é promissora e pode ser utilizada para compor um sistema CAD na tarefa de detectar regiões de massas.
343

Determina??o dos indicadores de efici?ncia econ?mica, composi??o dos custos de produ??o e principais ?ndices zoot?cnicos em propriedades leiteiras na regi?o Norte Fluminense / Determination of indicators of economic efficiency, breakdown of production and major Indices husbandry on dairy farms in the North Fluminense-RJ.

RAGAZZI, Fernanda Gi?como 04 July 2014 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-11T18:42:22Z No. of bitstreams: 1 2014 - Fernanda Gi?como Ragazzi.pdf: 649927 bytes, checksum: 083760648fee0ef57cb383ea4a51d569 (MD5) / Made available in DSpace on 2017-05-11T18:42:22Z (GMT). No. of bitstreams: 1 2014 - Fernanda Gi?como Ragazzi.pdf: 649927 bytes, checksum: 083760648fee0ef57cb383ea4a51d569 (MD5) Previous issue date: 2014-07-04 / CAPES / The dairy cattle exploration in Brazil is an important activity in the economic and social development process of the country. The aim of this study was to analyze production indices: birth rate, calving interval, service period and milk production, as well as, indicators of economic efficiency: crude margin, net margin and result (profit or loss) and the composition of production costs of 20 dairy farms in the Norte Fluminense. Were determined the components of the production costs: operating cost, effective operational cost and total cost. The dairy farms obtained the following averages for production indices: birth rate of 57.4 ? 12.18% with a coefficient of variation of 21.22%, calving interval of 13.5 ? 0.68 months with a coefficient of variation 5.05%, period of 116.2 ? 9.23 days service with a coefficient of variation of 7.95% and milk production of 6.1 ? 2.58 liters per day with a coefficient of variation of 41.96 %. Average crude margin of R$ 32,514.51 ? R$ 20,905.58 with a coefficient of variation of 64.30% and an average net margin of R$ 29,239.05? R$ 20,840.88 with a coefficient of variation of 71.28% was found, and producers remain in business in the short term is possible pay the actual operating cost. And result (loss), on average - R$ 124,050.95 ? R$ 27,757.68 with a coefficient of variation of 22.38%. By presenting injury, revenues does not remunerate investment, ie, the financial fixed assets in equity as land, improvements and so on. The low production indicex regarding the birth rate and milk production must be improved to obtain higher revenues in the activity and better milk production. The highest percentage of participation in the composition of revenue and the costs of investment was the asset value when recorded, and the sale of milk and the purchase of animals, respectively, when not accounted for this item. Regarding expenses with funding, the highest percentages were related to labor, grazing, concentrated feed and roughage supplementation. Producers remain analyzed short-term activity, but for improvement in production should be production indices with greater use of technical assistance for the return on economic efficiency. / A explora??o da bovinocultura de leite no Brasil constitui importante atividade no processo de desenvolvimento econ?mico e social do Pa?s. O objetivo do presente trabalho foi analisar os ?ndices zoot?cnicos: taxa de natalidade, intervalo de partos, per?odo de servi?o e produ??o de leite, bem como, os indicadores de efici?ncia econ?mica: margem bruta, margem l?quida e resultado (lucro ou preju?zo) e a composi??o dos custos de produ??o de 20 propriedades leiteiras na regi?o Norte Fluminense. Foram determinados os componentes do custo de produ??o: custo operacional, custo operacional efetivo e custo total. As propriedades leiteiras obtiveram as seguintes m?dias para os ?ndices zoot?cnicos: taxa de natalidade de 57,4 ? 2,18% com coeficiente de varia??o de 21,22%, intervalo de partos de 13,5 ? 0,68 meses com coeficiente de varia??o de 5,05%, per?odo de servi?o de 116,2 ? 9,23 dias com coeficiente de varia??o de 7,95% e produ??o de leite de 6,1?2,58 litros por dia com coeficiente de varia??o de 41,96%. Foi encontrada margem bruta m?dia de R$ 32.514,51 ? R$ 20.905,58 com coeficiente de varia??o de 64,30% e margem l?quida m?dia de R$ 29.239,05 ? R$ 20.840,88 com coeficiente de varia??o de 71,28%, permitindo aos produtores permanecerem na atividade no curto prazo sendo poss?vel o pagamento do custo operacional efetivo. E resultado (preju?zo) na m?dia de - R$ 124.050,95 ? R$ 27.757,68 com coeficiente de varia??o de 22,38%. Por apresentar preju?zo, a receita obtida n?o remunera o investimento realizado, ou seja, o ativo financeiro imobilizado em patrim?nio como terras, benfeitorias e etc. Os baixos ?ndices zoot?cnicos referentes ? taxa de natalidade e produ??o de leite devem ser melhorados para obten??o de maiores receitas na atividade e melhor produ??o de leite. A maior porcentagem de participa??o na composi??o das receitas e nas despesas de investimento foi o valor imobilizado, quando contabilizado, e a venda do leite e a compra de animais, respectivamente, quando n?o contabilizado, o valor imobilizado. Com rela??o ?s despesas com custeio, as maiores porcentagens foram referentes ? m?o de obra, a pastagem, a alimenta??o concentrada e a suplementa??o volumosa. Os produtores analisados permanecem no curto prazo na atividade, por?m para aumentar a produ??o devem ter melhorados os ?ndices zoot?cnicos com maior utiliza??o da assist?ncia t?cnica para obten??o de maior retorno de efici?ncia econ?mica.
344

Reprodutibilidade e correlação in vivo dos métodos visuais e de fluorescência a laser na detecção de descolorações em sulcos e fossetas oclusais de molares decíduos / In vivo reproducibility and correlation of visual and laser fluorescence methods for the detection of pits and fissures with discoloration in primary molars

Alessandra Cristina da Silva Nassif 13 December 2006 (has links)
Com o intuito de estudar in vivo a reprodutibilidade e a comparação de dois índices visuais (Ekstrand et al. (1998) ? E e Nyvad; Machiulskiene e Baelum (1999) ? N) e as medidas de fluorescência a laser AGNOdent®,KaVo - DD) na detecção de sulcos e fossetas descoloridos, um único examinador treinado, após a obtenção do consentimento livre e esclarecido de 28 pacientes, atribuiu os escores E, N e médias de fluorescência a laser de 190 molares decíduos com e sem descoloração em sulcos e fossetas oclusais. A reprodutibilidade dos índices visuais foi calculada a partir do teste kappa Cohen e kappa ponderado (kp), enquanto para as médias do DD foi calculado o índice de correlação de Pearson (rp). Para a comparação entre os índices visuais ainda se calculou a correlação de Spearman (rcs) e para a correlação entre os índices visuais e as médias do DD, foram aplicados o teste t de Student para as dicotomizações de presença de lesão, descoloração e atividade. Finalmente, foi calculada a análise de variância (ANOVA) para comparação entre as médias do DD e os graus de severidade das lesões. A reprodutibilidade dos índices visuais foi substancial (kpE = 0,645) e (kpN = 0,634) e as médias do DD apresentaram correlação de Pearson significativa e altamente positiva (rp = 0,930). A comparação entre os índices visuais também foi positiva e significativa principalmente quanto à severidade (rcs = 0,623) e nas dicotomizações para a presença de lesão (rcs = 0,765) e descoloração (rcs = 0,757). O teste t de Student para as comparações entre os índices e as médias do DD também se apresentaram significativos (p < 0,001) para presença de lesão e descoloração ao contrário dos resultados para atividade. A análise de variância entre os graus de severidade dos índices visuais e as médias do DD mostrou diferenças estaticamente significativas apenas entre os graus de severidade 0 e 1 (E - 2a) para o índice E e 0, 1 (N - 4) e 2 (N - 5) para o índice N. Conclui-se, para sulcos e fossetas descoloridos de molares decíduos, que (1) ambos os métodos (visuais e de fluorescência a laser) mostraram-se confiáveis (2) o DD foi capaz de diferenciar tecidos hígidos de lesões com descoloração e de (3) inativas intactas ou com microcavidades em esmalte. / Aiming at developing an in vivo study of the reproducibility and correlation of two visual indexes (Ekstrand et al. (1998) ? E and Nyvad; Machiulskiene and Baelum (1999) ? N) and the measures of laser fluorescence (DIAGNOdent®,KaVo - DD) for the detection of decolorised pits and fissures, a single trained examiner, after the free and aware consent of 28 patients, opened the scores E, N and laser fluorescence averages of 190 primary molars with and without occlusal discoloration in pits and fissures. The reproducibility of the visual indexes was calculated with basis on the kappa Cohen and weighted kappa (wk) tests, while for the DD averages the Perason´s correlation (rp) was calculated. To provide a comparison among the visual indexes, the Sperman´s correlation (rcs) was calculated, and for the correlation among the visual indexes and the DD averages, the Student´s t test and the one-way analysis of variance (ANOVA) were applied to compare the DD averages and the degree of severity of the lesions. The reproducibility of the visual indexes was substantial (wkE= 0,645) and (wkN= 0,634); the DD averages presented a significant and highly positive Pearson´s correlation (rP= 0,930). The comparison among the visual indexes proved to be positive and significant, mainly in relation to the severity (rcs= 0,623) and the dichotomisations for the presence of lesion (rcs= 0,765) and discoloration (rcs= 0,757). The Student´s t test of for the comparisons among the indexes and the DD averages also proved to be significant (p < 0,001) for the presence of lesion and discoloration, contrary to the activity results. The one-way analysis of variance (ANOVA) among the degrees of severity and DD averages showed significant differences only at the degrees 0 and 1 (E ? 2a) of the E index and 0, 1 (N ? 4) and 2 (N ? 5) of the N index. The conclusions for pits and fissures with discoloration in primary molars are that (1) both methods (visual and laser fluorescence) were reliable (2) the DD was able to diferenciatte sound tissues from lesions with discoloration and (3) inactive intact or with microcavities lesions at the enamel level.
345

Reprodutibilidade e correlação in vivo dos métodos visuais e de fluorescência a laser na detecção de descolorações em sulcos e fossetas oclusais de molares decíduos / In vivo reproducibility and correlation of visual and laser fluorescence methods for the detection of pits and fissures with discoloration in primary molars

Nassif, Alessandra Cristina da Silva 13 December 2006 (has links)
Com o intuito de estudar in vivo a reprodutibilidade e a comparação de dois índices visuais (Ekstrand et al. (1998) ? E e Nyvad; Machiulskiene e Baelum (1999) ? N) e as medidas de fluorescência a laser AGNOdent®,KaVo - DD) na detecção de sulcos e fossetas descoloridos, um único examinador treinado, após a obtenção do consentimento livre e esclarecido de 28 pacientes, atribuiu os escores E, N e médias de fluorescência a laser de 190 molares decíduos com e sem descoloração em sulcos e fossetas oclusais. A reprodutibilidade dos índices visuais foi calculada a partir do teste kappa Cohen e kappa ponderado (kp), enquanto para as médias do DD foi calculado o índice de correlação de Pearson (rp). Para a comparação entre os índices visuais ainda se calculou a correlação de Spearman (rcs) e para a correlação entre os índices visuais e as médias do DD, foram aplicados o teste t de Student para as dicotomizações de presença de lesão, descoloração e atividade. Finalmente, foi calculada a análise de variância (ANOVA) para comparação entre as médias do DD e os graus de severidade das lesões. A reprodutibilidade dos índices visuais foi substancial (kpE = 0,645) e (kpN = 0,634) e as médias do DD apresentaram correlação de Pearson significativa e altamente positiva (rp = 0,930). A comparação entre os índices visuais também foi positiva e significativa principalmente quanto à severidade (rcs = 0,623) e nas dicotomizações para a presença de lesão (rcs = 0,765) e descoloração (rcs = 0,757). O teste t de Student para as comparações entre os índices e as médias do DD também se apresentaram significativos (p < 0,001) para presença de lesão e descoloração ao contrário dos resultados para atividade. A análise de variância entre os graus de severidade dos índices visuais e as médias do DD mostrou diferenças estaticamente significativas apenas entre os graus de severidade 0 e 1 (E - 2a) para o índice E e 0, 1 (N - 4) e 2 (N - 5) para o índice N. Conclui-se, para sulcos e fossetas descoloridos de molares decíduos, que (1) ambos os métodos (visuais e de fluorescência a laser) mostraram-se confiáveis (2) o DD foi capaz de diferenciar tecidos hígidos de lesões com descoloração e de (3) inativas intactas ou com microcavidades em esmalte. / Aiming at developing an in vivo study of the reproducibility and correlation of two visual indexes (Ekstrand et al. (1998) ? E and Nyvad; Machiulskiene and Baelum (1999) ? N) and the measures of laser fluorescence (DIAGNOdent®,KaVo - DD) for the detection of decolorised pits and fissures, a single trained examiner, after the free and aware consent of 28 patients, opened the scores E, N and laser fluorescence averages of 190 primary molars with and without occlusal discoloration in pits and fissures. The reproducibility of the visual indexes was calculated with basis on the kappa Cohen and weighted kappa (wk) tests, while for the DD averages the Perason´s correlation (rp) was calculated. To provide a comparison among the visual indexes, the Sperman´s correlation (rcs) was calculated, and for the correlation among the visual indexes and the DD averages, the Student´s t test and the one-way analysis of variance (ANOVA) were applied to compare the DD averages and the degree of severity of the lesions. The reproducibility of the visual indexes was substantial (wkE= 0,645) and (wkN= 0,634); the DD averages presented a significant and highly positive Pearson´s correlation (rP= 0,930). The comparison among the visual indexes proved to be positive and significant, mainly in relation to the severity (rcs= 0,623) and the dichotomisations for the presence of lesion (rcs= 0,765) and discoloration (rcs= 0,757). The Student´s t test of for the comparisons among the indexes and the DD averages also proved to be significant (p < 0,001) for the presence of lesion and discoloration, contrary to the activity results. The one-way analysis of variance (ANOVA) among the degrees of severity and DD averages showed significant differences only at the degrees 0 and 1 (E ? 2a) of the E index and 0, 1 (N ? 4) and 2 (N ? 5) of the N index. The conclusions for pits and fissures with discoloration in primary molars are that (1) both methods (visual and laser fluorescence) were reliable (2) the DD was able to diferenciatte sound tissues from lesions with discoloration and (3) inactive intact or with microcavities lesions at the enamel level.
346

Coleta seletiva com inclusão de catadores: construção participativa de indicadores e índices de sustentabilidade / Selective waste collection with waste pickers inclusion: participatory construction of sustainability indicators and indexes

Besen, Gina Rizpah 28 February 2011 (has links)
No Brasil, em 2008, 994 municípios (18 por cento) praticavam a coleta seletiva, 66 por cento deles em parceria com catadores de materiais recicláveis, organizados em associações e cooperativas. O aumento destas iniciativas demanda avaliação quanto ao seu desempenho tanto no plano operacional quanto no socioambiental. A elaboração de indicadores e índices para avaliar e monitorar a sustentabilidade da coleta seletiva e de organizações de catadores, de forma participativa, constitui instrumentos relevantes para a consolidação da coleta seletiva e o fortalecimento das organizações de catadores. Nesse sentido, se identificou, construiu e validou indicadores de sustentabilidade para a gestão, avaliação e monitoramento com o objetivo de fortalecer sua inserção nos sistemas municipais de resíduos sólidos e sua interface com a inclusão social e a saúde pública. Realizou-se pesquisa qualitativa e quantitativa, por meio de: 1) aplicação de duas rodadas de questionários por meio eletrônico, junto a 88 especialistas no país, utilizando-se a Técnica Delphi, com retorno de 67 por cento na primeira rodada e 72,9 por cento na segunda; 2) oficinas regionais, em quatro cidades do país envolvendo atores diversos que atuam com a temática e, 3) oficinas específicas com organizações de catadores, técnicos municipais e de organização não governamental. Os participantes validaram duas definições de sustentabilidade, uma para a coleta seletiva e uma para organizações de catadores. A partir do processo de validação e ponderação de indicadores construíram-se duas matrizes de sustentabilidade para o cálculo dos índices de sustentabilidade; uma com 14 indicadores para a coleta seletiva municipal e outra com 21 para organizações de catadores, com as respectivas formas de cálculo e tendências à sustentabilidade. Elaborou- se também dois instrumentos de comunicação (Radares da Sustentabilidade) para facilitar o entendimento por público mais amplo e direcionar o monitoramento. A meta é disseminar estes indicadores para que possam ser aplicados em políticas públicas e aperfeiçoados / In Brazil, in 2008, 994 municipalities (18 per cent) practiced selective waste collection, 66 per cent of them in partnership with waste pickers organized in cooperatives and associations. The increase of municipal initiatives demands an analysis/evaluation related to its performance at the operational level as well as socio-environmental. The construction of indicators and indexes to assess the sustainability of selective waste collection and waste pickers organizations, in a participatory way, represent relevant tools for the consolidation and strengthening of selective waste collection and the organizations. This implied in the identification, development and validation, to strengthen its insertion within the municipal solid waste management system and its interface with social inclusion and public health. The research was based on quantitative and qualitative study, carried out through: 1) implementation of two rounds of questionnaires sent through electronic way to 88 experts within the country, using the Delphi Technique, with a return rate of 67 per cent in the first round, and 72.9 per cent in the second; 2) regional workshops in four cities involving several actors who work with the theme, and 3) workshops with waste pickers organizations, technicians of the municipal government and from a non-governmental organization. The participants validated two definitions of sustainability, one for the selective waste collection and other for waste pickers organizations. The validation and weighting of indicators enabled the construction of two matrixes of sustainability, to calculate sustainability indexes, with 14 indicators for selective municipal waste collection and 21 for the organizations, with their respective means of calculation and sustainability trends. Two instruments of communication (Radars of Sustainability) were also developed to facilitate the understanding and monitoring by a larger public. The goal is to disseminate these indicators so that they can be implemented by public policies
347

Caractérisation automatique d’organisations cellulaires dans des mosaïques d’images microscopiques de bois / Automatic characterization of the cell organization in light microscopic images of wood : application to the identification of the cell file

Brunel, Guilhem 01 October 2014 (has links)
Ce travail porte sur l'analyse d'images numériques biologiques. Il vise à définir et mettre en œuvre des processus de mesures automatiques de données biologiques à partir d'images numériques dans un cadre de traitement de masse, et aborde notamment : l'incidence des choix méthodologiques sur la stabilité des résultats, l'étude de la validation des mesures produites et les limites de la généricité des méthodes et modèles appliquées à la biologie végétale.La réflexion est menée dans le cadre de l'étude de certaines organisations cellulaires, et plus particulièrement de l'identification et l'analyse automatique de files cellulaires dans des mosaïques d'images microscopiques de bois. En effet, l'étude des tendances biologiques le long de ces structures est nécessaire pour comprendre la mise en place des différentes organisations et maturations de cellule. Elle ne peut être conduite qu'à partir d'une grande zone d'observation du plan ligneux. Pour cela,- nous avons mis en place un nouveau protocole de préparation (rondelles de bois poncées) et de numérisation des échantillons permettant d'acquérir entièrement la zone d'observation sans biais- nous avons développé une chaîne de traitement permettant l'extraction automatique des files cellulaires dans des mosaïques images numériques.- nous avons proposé des indices de fiabilité pour chaque mesure effectuée afin de mieux cibler les études statistiques à venir.Les méthodes développées dans la thèse permettent l'acquisition et le traitement rapide d'un volume important de données. Ces données devraient servir de base à de nombreuses investigations : des analyses architecturales des arbres avec le suivi de file cellulaire et/ou la détection de perturbations biologiques, des analyses de variabilité intra et inter arbres permettant de mieux comprendre la croissance endogène des arbres. / This study focuses on biological numeric picture processes. It aims to define and implement new automated measurements at large scale analysis. Moreover, this thesis addresses: The incidence of the proposed methodology on the results reliability measurements accuracy definition and analysis proposed approaches reproducibility limits when applied to plant biology.This work is part of cells organization study, and aims to automatically identify and analyze the cell lines in microscopic mosaic wood slice pictures. Indeed, the study of biological tendencies among the cells lines is necessary to understand the cell migration and organization. Such a study can only be realized from a huge zone of observation of wood plane. To this end, this work proposes:- a new protocol of preparation (slices of sanded wood) and of digitizing of samples, in order to acquire the entire zone of observation without bias,- a novel processing chain that permit the automated cell lines extraction in numeric mosaic pictures,- reliability indexes for each measurement for further efficient statistical analysis.The methods developed during this thesis enable to acquire and treat rapidly an important volume of information. Those data define the basis of numerous investigations, such as tree architectural analysis cell lines following and/or detection of biological perturbations. And it finally helps the analysis of the variability intra- or inter- trees, in order to better understand the tree endogenous growth.
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Análise das chuvas diárias na região de São Carlos/SP por meio de índices climáticos e das tendências pluviométricas / Analysis of daily rainfall in São Carlos/SP using climatic indexes and trend test

Sanches, Rafael Grecco 28 June 2019 (has links)
A heterogeneidade dos elementos que compreendem a climatologia tropical se evidencia no comportamento das chuvas nessa região macroclimática. Para tanto, compreender seu comportamento temporal e espacial assume grande relevância, em função do impacto dessas na dinâmica urbana e rural, bem como para seu planejamento estratégico. Verificar seu curso interanual em episódios diários é grande desafio, nesse sentido. Com isso, o estudo objetivou analisar as chuvas diárias na região de São Carlos/SP, a fim de compreender sua evolução temporal e espacial, além de avaliar possíveis tendências para essa, que se insere na dinâmica tropical (sazonalmente chuvoso/estiagem). Foram analisados 39 anos de dados diários de chuvas, em 7 postos pluviométricos, e que estiveram com, ao menos, 95% dos dados consistentes. Utilizou-se de índices climáticos (script RClimdex) e do Laplace trend factor para analisar os dados temporais históricos e de tendência. Observou-se que os valores dos índices flutuam entre as estações, mas que esses estão associados aos fenômenos da ZCAS (Zona de Convergência do Atlântico Sul) e dos SFs (Sistemas Frontais), que regem o clima no sudeste da América do Sul. Além disso, notou-se que o sul da área estudada apresenta maior concentração pluviométrica, em função dos aspectos geomorfológicos (e até de ocupação), bem como notou-se o aumento de episódios extremos de chuvas diárias. As chuvas diárias, portanto, tendem a concentração, uma vez que os volumes anuais diminuem ou aumentam (ciclicamente), mas notam-se precipitações pluviométricas mais intensas (mm) em dias chuvosos, além do aumento da tendência dos dias com chuvas extremas. Futuros estudos que ampliem a área de estudo e possíveis correlações poder-se-ão reafirmar tais resultados, conforme verificado em estudos prévios. / Rainfall shows the heterogeneity of tropical climatology. Temporal and spatial behavior is highly relevant to verify the impact on urban and rural dynamics and strategic planning. The inter-annual course in daily episodes is the biggest challenge in that regard. The objective of this study was to analyze daily rainfall in the São Carlos/SP region, understand its temporal and spatial evolution, as well as to evaluate possible trends for this, which are part of tropical (seasonally rainy/dry) dynamics. A total of 39 years of daily rainfall data were analyzed in 7 pluviometric stations, with at least 95% of the data consistent using Climatic indexes (RClimdex script), and the Laplace trend factor to analyze temporal and trend data. It was observed that the values of the indexes fluctuate between the stations. These are associated with the phenomena of the South Atlantic Convergence Zone (SACZ) and SFs (Frontal Systems), which regulates the climate in the south-east of South America. Also, the south of the studied area presents a higher rainfall concentration, due to the geomorphological (and even occupation) aspects, as well as the increase of extreme episodes of daily rains. Therefore, daily rains tend to concentrate, since annual volumes decrease or increase (cyclically), but the rainfall (mm) is more intense on rainy days, in addition to the increase in the tendency of the days with extreme rains. Future studies that broaden the area of study and possible correlations may reaffirm such results, as verified in previous studies.
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QUALITY MEASUREMENT AND QUALITY IN PRICES INDEXES

GATTINI, LUCA 03 February 2010 (has links)
Rapid technical progress has increased the speed of quality change. Its impact has a large scale effect on a broad set of variables and it has exacerbated a latent economic problem on the measurement of true economic variables. For example, the reliability of the Consumer Price Index (CPI) has been increasingly undermined since it has been argued that price indexes suffer either an upward or a downward bias due to quality change in goods and services. This paper is aimed to be a comprehensive survey on historical contributions to modeling quality from a theoretical perspective. The fundamental contributions of several economists are framed into a coherent building block. We construct a general framework for quality adjustment in price index theory which helps to understand the importance of economic theory for price index definitions. Supply and demand side models are analysed and merged into Rosen (1974) model, the first well grounded attempt to construct a general equilibrium explanation to quality choices. First, we address the issue of quality measures into price index theory. Then, we present a survey of the relevant contributions to hedonic price modeling. We focus on two main fields of applied analysis: (1) determining how the price of a unit of commodity varies with the set of attributes; (2) estimating the demand and supply functions for the attributes of products. The open issues on quality adjustment in consumer price indexes will be analysed in the two applied papers, namely chapter 3 and chapter 4. They are two applied original contributions to hedonic price literature. Chapter 3: In this paper we show that a real time measure of pure price change for different varieties of non durable volatile and seasonal products is possible. Moreover, we introduce the idea of unobservable elements captured by brand specific and by time specific dummies. In order to compute a pure price index, a theoretically correct quality adjustment procedure has been determined where quality is measured in terms of attributes (Griliches, 1971a, 1971b; Tauchen and Witte, 2001; Pakes, 2003; Ekeland et al. 2002, 2004; Triplett 2004) and it is becomes a ’fundamental’ of the market. We have analyzed the prices of apples and oranges traded in the General Milan Market for fruit and vegetables. We have used a large amount of information from more than 8000 of observations collected between 2000 and 2004. We have found that quality is changed over time even if new goods/varieties were not introduced. Price levels adjusted for qualitative levels, measured in terms of the content of characteristics, are above the Laspeyres hedonic price index on average for apples whilst the pure price index for oranges is close to the Laspeyres price index. Our empirical analysis shows that a price index, which does not account for quality change, is underepresiting inflation for apples and correctly measuring price changes for oranges. Chapter 4: The relevant literature dealing with the problem of quality measurement in passenger cars (inter alias, Ohta and Griliches 1976, 1983; Lancaster (1966), Rosen (1974), Berry et al. 1995; 2004) relies on general hedonic imputation methods for the assessment of the quality adjusted price index. We deviate from this standard approach by computing a new quality adjusted index for cars based on a weighted adjustment procedure which accounts for attrition due to observable elements (Fitzgerald et al., 1998; Nevo, 2003; Horowitz and Manski, 1998). By doing this, we are able to define a quality adjusted price index which generates a more accurate identification of price index levels than the current state of the art. We use data for the universe of new cars and their characteristics, sold between 2000 and 2007 in Italy, and we identify the basic reference unit. Based on this we study the pricing behavior of the firms. We model a non random and non ignorable selection process based on an entry/exit process of cars (Olly and Pakes, 1996) due to profit maximizing firms in a differentiated product space. We find that the official index is overestimating inflation since our results point to a mild deflation. However we show that traditional hedonic techniques lead to an overestimation of quality improvement and consequently they under-estimate inflation.
350

The relationship between carry trade currencies and equity markets, during the 2003-2012 time period

Dumitrescu, Andrei, Tuovila, Antti January 2013 (has links)
One of the most popular investment and trading strategies over the last decade, has been the currency carry trade, which allows traders and investors to buy high-yielding currencies in the Foreign Exchange spot market by borrowing, low or zero interest rate currencies in the form of pairs, such as the Australian Dollar/Japanese Yen (AUD/JPY), with the purpose of investing the proceeds afterwards into fixed-income securities.To be able to determine the causality between the returns of equity markets and the foreign exchange market, we choose to observe the sensitivity and influence of two equity indexes on several pairs involved in carry trading. The reason for studying these relationships is to further explain the causes of the uncovered interest parity puzzle, thus adding our contribution to the academic field through this thesis.To accomplish our goals, data was gathered for daily quotes of 16 different currency pairs, grouped by interest differentials, and two equity indexes, the S&amp;P 500 and FTSE All-World, along with data for the VIX volatility index, for the 2003-2012 period. The data was collected from Thomson Reuters Datastream and the selected ten year span was divided into three different periods. This was done in order to discover the differences on how equity indexes relate to typical carry trade currency pairs, depending on market developments before, during and after the world financial crisis.The tests conducted on the collected data measured the correlations, influences and sensitivity for the 16 different currency pairs with the S&amp;P 500 Index, the FTSE All-World index, and the volatility index between the years of 2003-2012. For influences and sensitivity, we performed Maximum Likelihood (ML) regressions with Generalized Autoregressive Conditional Heteroscedasticity (GARCH) [1,1], in Eviews software.After analyzing the results, we found that, during our chosen time period, the majority of currency pair daily returns are positively correlated with the equity indexes and that the FX pairs show greater correlation with the FTSE All-World, than with the S&amp;P 500. Factors such as the interest rate of a currency and the choice of funding currency played an important role in the foreign exchange markets, during the ten year time span, for every yield group of FX pairs.Regarding the influence and sensitivity between currency pairs and the S&amp;P 500 with its VIX index, we found that our models explanatory power seems to be stronger when the interest rate differential between the currency pairs is smaller. Our regression analysis also uncovered that the characteristics of an individual currency can show noticeable effects for the relationship between its pair and the two indexes.

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