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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

Desenvolvimento de t?cnicas de classifica??o supervisionada para dados qu?micos multivariados / Development of supervised classification techniques for multivariate chemical data

Morais, Camilo de Lelis Medeiros de 29 September 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-01T21:32:48Z No. of bitstreams: 1 CamiloDeLelisMedeirosDeMorais_DISSERT.pdf: 7776134 bytes, checksum: df3df5fbaaa77afcd7e4306d1584bec9 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-07T23:52:52Z (GMT) No. of bitstreams: 1 CamiloDeLelisMedeirosDeMorais_DISSERT.pdf: 7776134 bytes, checksum: df3df5fbaaa77afcd7e4306d1584bec9 (MD5) / Made available in DSpace on 2017-11-07T23:52:52Z (GMT). No. of bitstreams: 1 CamiloDeLelisMedeirosDeMorais_DISSERT.pdf: 7776134 bytes, checksum: df3df5fbaaa77afcd7e4306d1584bec9 (MD5) Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Esta disserta??o consiste de um aporte te?rico sobre a constru??o de t?cnicas de classifica??o supervisionada para aplica??es em dados qu?micos multivariados. Para isso, t?cnicas quimiom?tricas baseadas em an?lise discriminante quadr?tica (QDA) e m?quinas de vetores suporte (SVM) foram constru?das em conjunto com an?lise de componentes principais (PCA), algoritmo de proje??es sucessivas (SPA) e algoritmo gen?tico (GA) para classifica??o supervisionada utilizando redu??o de dados e sele??o de vari?veis. Essas t?cnicas foram empregadas na an?lise de dados de primeira ordem, constitu?dos de espectros na regi?o do infravermelho m?dio com transformada de Fourier e reflect?ncia total atenuada (ATR-FTIR); espectros de massas obtidos por cromatografia l?quida com um detector por tempo de v?o (LC/TOF); e espectros de massas obtidos por desor??o/ioniza??o por laser de superf?cie acoplado a um detector por tempo de v?o (SELDI-TOF). Os dados de ATR-FTIR foram utilizados para diferenciar duas classes de fungos do g?nero Cryptococcus, enquanto que os dados de espectrometria de massas foram utilizados para identificar c?ncer de ov?rio e de pr?stata em soro sangu?neo. Al?m disso, novas t?cnicas de an?lise discriminante bidimensionais utilizando an?lise de componentes principais com an?lise discriminante linear (2D-PCA-LDA), an?lise discriminante quadr?tica (2D-PCA-QDA) e m?quinas de vetores suporte (2D-PCA-SVM) foram desenvolvidas para aplica??es em dados qu?micos de segunda ordem compostos por matrizes de excita??o-emiss?o (EEM) por fluoresc?ncia molecular em amostras simuladas e reais. Os resultados obtidos mostraram que as t?cnicas desenvolvidas tiveram alto desempenho classificat?rio tanto para os dados de primeira quanto de segunda ordem, com taxas de acerto, sensibilidade e especificidade atingindo valores entre 90 a 100%. Al?m disso, as t?cnicas bidimensionais desenvolvidas tiveram, no geral, desempenho superior do que os m?todos tradicionais de classifica??o multivariada utilizando dados desdobrados, o que mostra seu potencial para outras futuras aplica??es anal?ticas. / This dissertation is composed by a theoretical contribution about the development of supervised classification techniques for application using multivariate chemical data. For this, chemometric techniques based on quadratic discriminant analysis (QDA) and support vector machines (SVM) were built combined with principal component analysis (PCA), successive projections algorithm (SPA) and genetic algorithm (GA) for supervised classification using data reduction and feature selection. These techniques were employed in analyzing first-order data, composed by attenuated total reflectance Fourier transform infrared spectroscopy (ATRFTIR) and mass spectra obtained from liquid chromatography time of flight (LC/TOF) and surface-enhanced laser desorption/ionization time of flight (SELDI/TOF). ATR-FTIR data were used to differentiate two classes of fungus of Cryptococcus gene, whereas the mass spectra data was used to identify ovarian and prostate cancer in blood serum. In addition, new twodimensional discriminant analysis techniques based on principal component analysis linear discriminant analysis (2D-PCA-LDA), quadratic discriminant analysis (2D-PCA-QDA) and support vectors machine (2D-PCA-SVM) were developed for applications in second-order chemical data composed by excitation-emission matrices (EEM) molecular fluorescence of simulated and real samples. The results show that the developed techniques had better classification performance for both first and second-order data, with classification rates, sensitivity and specificity reaching values between 90 to 100%. Also, the developed twodimensional techniques had overall performance superior than traditional multivariate classification methods using unfolded data, showing its potential to other future analytical applications.
2

Diagn?stico da degrada??o ambiental no munic?pio de Areia Branca-RN por geotecnologias / Diagnosis of environmental degradation in the city of Areia Branca-RN by geotechnology

Silva, Gabriella Cynara Minora da 25 February 2013 (has links)
Made available in DSpace on 2014-12-17T15:55:04Z (GMT). No. of bitstreams: 1 GabriellaCMS_DISSERT.pdf: 3451606 bytes, checksum: 1ee33015b3633fb79771b6160bff6a6c (MD5) Previous issue date: 2013-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The municipality of Areia Branca is within the mesoregion of West Potiguar and within the microregion of Mossor?, covering an area of 357,58 km2. Covering an area of weakness in terms of environmental, housing, together with the municipality of Grossos-RN, the estuary of River Apodi-Mossor?. The municipality of Areia Branca has historically suffered from a lack of planning regarding the use and occupation of land as some economic activities, attracted by the extremely favorable natural conditions, have exploited their natural resources improperly. The aim of this study is to quantify and analyze the environmental degradation in the municipality. Thus initially was performed a characterization of land use using remote sensing, geoprocessing and geographic information system GIS in order to generate data and information on the municipal scale, which may serve as input to the environmental planning and land use planning in the region. From this perspective, were used a Landsat 5 image TM sensor for the year 2010. In the processing of this image was used SPRING 5.2 and applied a supervised classification using the classifier regions, which was employed Bhattacharya Distance method with a threshold at 30%. Thus was obtained the land use map that was analyzed the spatial distribution of different types of the use that is occurring in the city, identifying areas that are being used incorrectly and the main types of environmental degradation. And further, were applied the methodology proposed by Beltrame (1994), Physical Diagnosis Conservationist under some adaptations for quantifying the level of degradation or conservation study area. As results, the indexes were obtained for the parameters in the proposed methodology, allowing quantitatively analyze the degradation potential of each sector. From this perspective, considering a scale of 0 to 100, sector A and sector B had value 31.20 units of risk of physical deterioration. And the C sector, has shown its value - 34.64 units degradation risk and should be considered a priority in relation to the achievement of conservation actions / O munic?pio de Areia Branca-RN est? inserido na mesorregi?o Oeste Potiguar e na microrregi?o de Mossor?, abrangendo uma ?rea de 357,58 km2. Compreende uma ?rea de fragilidade do ponto de vista ambiental, pois abriga, juntamente com o munic?pio de Grossos- RN, o estu?rio do rio Apodi-Mossor?. O munic?pio de Areia Branca vem sofrendo historicamente com a falta de planejamento no tocante ao uso e ocupa??o do solo, uma vez que algumas atividades econ?micas, atra?das pelas condi??es naturais favor?veis, t?m explorado os recursos naturais de forma inadequada. O objetivo deste estudo ? quantificar e analisar a degrada??o ambiental no referido munic?pio. Para isso, inicialmente foi realizada uma caracteriza??o do uso do solo, utilizando sensoriamento remoto, geoprocessamento e um sistema de informa??es geogr?ficas - SIG, visando gerar dados e informa??es na escala municipal, que possam servir de subs?dio para o planejamento ambiental e o ordenamento territorial da regi?o. Nessa perspectiva, utilizou-se uma imagem Landsat 5, sensor TM referente ao ano de 2010. No processamento desta imagem foi utilizado o SPRING 5.2 e aplicado uma classifica??o supervisionada atrav?s do classificador por regi?es, onde foi empregado o m?todo Bhattacharya Distance com um limiar 30%. Com isso foi obtido o mapa de uso do solo a partir do qual analisou-se a distribui??o espacial dos diferentes tipos de uso que ocorrem no munic?pio, identificando ?reas que est?o sendo utilizadas de maneira incorreta e os principais tipos de degrada??o ambiental. Em prosseguimento, aplicou-se a metodologia proposta por Beltrame (1994), o Diagn?stico F?sico-Conservacionista, sob algumas adapta??es, para obter a quantifica??o do n?vel de degrada??o ou conserva??o da ?rea de estudo. Como resultados, foram obtidos os ?ndices para os par?metros propostos na metodologia, permitindo analisar quantitativamente o potencial de degrada??o de cada setor. Nessa perspectiva, considerando uma escala de 0 a 100, o setor A e o setor B apresentaram valor 31,20 unidades de risco de degrada??o f?sica. E o setor C, demonstrou valor 34,64 unidades de risco de degrada??o, devendo ser considerado prioridade no tocante ? realiza??o de a??es conservacionistas

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