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Multichannel analysis of object-color spectra /Seitz Vent, Debra S. January 1994 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references (leaves 168-171).
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NON-INVASIVE OPTICAL DETECTION OF EPITHELIAL CANCER USING OBLIQUE INCIDENCE DIFFUSE REFLECTANCE SPECTROSCOPYGarcia-Uribe, Alejandro 16 January 2010 (has links)
This dissertation describes the design, fabrication and testing of an oblique incidence
diffuse reflectance spectrometry (OIDRS) system for in-vivo and noninvasive detection
of epithelial cancer. Two probes were fabricated using micromachining technology,
which plays a significant role in the probe development by enabling device
miniaturization, low-cost fabrication and precise assembly. The fist probe was developed
and clinically tested for skin cancer detection. This probe consists of three source fibers,
two linear array of collection fibers and four micromachined positioning devices for
accurate alignment of the fibers. The spatially resolved diffuse reflectance spectra from
167 pigmented and 78 non-pigmented skin abnormalities were measured and used to
design a set of classifiers to separate them into benign or malignant ones. These
classifiers perform with an overall classification rate of 91%. The absorption and
reduced scattering coefficient spectra were estimated to link the anatomic and
physiologic properties of the lesions with the optical diagnosis. The melanoma cases
presented larger average absorption and reduced scattering spectra than the dysplastic
and benign ones. A second probe was designed to demonstrate the feasibility of a miniaturized ?side viewing? optical sensor probe for OIDRS. The sensor probe consists
of a lithographically patterned polymer waveguides chip and two micromachined
positioning substrates. This miniaturize probe was used to measure twenty ex-vivo
esophageal samples. Two statistical classifiers were designed to separate the esophageal
cases. The first one distinguishes benign and low dysplastic from high dysplastic and
cancerous lesions. The second classifier separates benign lesions from low dysplastic
ones. Both classifiers generated a classification rate of 100%.
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Espectroscopia de imageamento e gamaespectrometria aerea e terrestre de pegmaticos e granitos da porção sul da Provincia Pegmatitica da Borborema (PPB), Nordeste do Brasil / Imagem spectroscopy and ground and aerial gama ray spectrometry of pegmatites and granites of Borborema Pegmatitic Province (BPP), Northeastern BrasilSilva, Sebastião Milton Pinheiro da 14 August 2018 (has links)
Orientadores: Alvaro Penteado Crosta, Hartmut Beurlen / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-14T18:20:54Z (GMT). No. of bitstreams: 1
Silva_SebastiaoMiltonPinheiroda_D.pdf: 16585343 bytes, checksum: 70c3444445e77b34a0b4aa6c35c60fd3 (MD5)
Previous issue date: 2009 / Resumo: Neste estudo foram utilizados dados de espectroscopia de reflectância (ER), imagens dos sensores Terra/ASTER e EO-1/Hyperion e dados de gamaespectrometria aérea e terrestre para caracterização espectromineralógica e gamaespectrométrica de pegmatitos e granitos pegmatíticos da porção sul da PPB. Por meio da ER foi possível caracterizar fases e misturas de fases minerais que compõem essas rochas, incluindo caulinita, muscovita, illita/sericita e turmalina em pegmatitos do tipo homogêneo. A aplicação da análise por principais componentes aos dados Terra/ASTER através da técnica Crósta resultou em um mapa exibindo a mineralogia principal dos pegmatitos homogêneos e heterogêneos da área de estudo, bem como dos quartzitos da Formação Equador, biotita xistos da Formação Seridó, além de coberturas superficiais limonitizadas associadas. No pegmatito do Alto do Giz, selecionado para um estudo detalhado, foram identificadas por meio da ER fases, e misturas de fases, de caulinita, illita/sericita, lepidolita, mica sódica, muscovita, cookeíta e turmalina, cujas associações contribuiram para definir uma zona litinífera (cookeita+lepidolita) nas bordas dos núcleos de quartzo N2 e N3 e o zoneamento interno do pegmatito. Com base nesses resultados é proposta sua classificação como do tipo complexo, sub-classe espodumênio. Além disso, foram reconhecidos pelo menos três estágios de sua evolução: um primeiro relacionado à cristalização de espodumênio, um outro de natureza hidrotermal, que deu origem à cookeita e, finalmente, e um terceiro estágio de caulinização ligado a processo hidrotermal e/ou supergênico. A análise e classificação espectral da imagem do sensor EO-1/Hyperion possibilitou mapear a distribuição das zonas do pegmatito Alto do Giz utilizando os minerais muscovita, caulinita e mica sódica como indicadores das distintas zonas. Com dados do aerolevantamento gamaespectrométrico do Projeto Seridó, reprocessados e reinterpretados utilizando métodos modernos, com apoio da gamaespectrometria terrestre, foi possível discriminar os quartzitos das regiões norte e sul da área de estudos, em função de suas distintas assinaturas do tório (eTh) e da razão eTh/K, bem como caracterizar os granitos pegmatíticos por meio das razões dos canais eU/eTh e eU/K. As imagens do tório (eTh) e da razão eTh/K permitiram identificar metaconglomerados e metarenitos ricos em minerais pesados, intercalados nos quartzitos da Formação Equador, e propor um novo tipo de mineralização torífera na Faixa Seridó. Determinações com MEV-EDS revelaram teores máximos de 79,4% de ThO2 e 87,7% de ETR (Ce, La, Nd) em monazitas; 99,2% de TiO2 em rutilo e 1,81% de HfO2 em zircão. Esses resultados demonstraram o destacado potencial para caracterização e mapeamento de granitos pegmatíticos da PPB com base em dados coletados há várias décadas e de baixa resolução espacial. O detalhamento realizado no granito Galo Branco por meio da coleta de dados de gamaespectrometria terrestre, dosagens radiométricas e determinações químicas por ICP-MS indicaram teores de 0,47 ppm a 7,8 ppm de urânio, de 0,1 ppm a 21 ppm de tório e de 2% a 5,24% de potássio. Essas concentrações irregularmente distribuídas sugerem mudanças de conteúdo e concentração de minerais acessórios durante os estágios de diferenciação e cristalização magmática desse granito. A ocorrência de diques de pegmatitos encaixados em quartzitos ao sul do granito Galo Branco foi revelada por meio das elevadas razões eU/eTh. / Abstract: Reflectance spectroscopy (ER), Terra/ASTER and EO-1/Hyperion images, and ground and aerial gamma ray data were employed for mineral characterization of pegmatites and pegmatitic granites in the southern portion of the BPP. ER results allowed to characterize mineral phases and mixtures of minerals including kaolinite, illite/sericite, muscovite and turmaline (schorl) in homogeneous pegmatites. Principal component analysis were applied to Terra/ASTER data using the Crósta techique, resulting in a map exhibiting the main mineralogy of homogeneous and heterogeneous pegmatites, as well as quartzites of the Equador Fm. biotite schists of the Serido Fm. and iron-rich superficial deposits. The Alto do Giz pegmatite was selected for a detailed study and mineral phases comprising kaolinite, muscovite, illite/sericite, Na- and Li-bearing micas, cookeite and tourmaline were recognized, allowing to define a lLi-rich zone (cookeite+lepidolite) around nuclei N2 and N3 and to establish the internal zoning of the pegmatite. Based on these results we proposed its classification as a complex-type pegmatite, of the spodumene sub-class. Furthermore, at least three evolution stages have been establish for Alto do Giz: an early stage represented by the primary crystallization of spodumene, followed by hydrothermal alteration that originated cookeite, and later stage comprising intense kaolinization originated from hydrothermal and/or supergenic processes. The analysis and spectral classification of the EO-1 Hyperion data allowed to map the spatial distribution of the distinct zones, based on the occurrence of key minerals such as muscovite, kaolinite, and Na-bearing mica. Using the airborne gamma ray data of the Seridó Aerogeophysical Project, reprocessed and reinterpreted using modern techniques, and using ground gamma data as a support, it was possible to distinguish quartzites from the north and south portions of the BPP based on their distinctive Th contents and on the eTh/K ratio, as well as to characterize pegmatitic granites using the ratios eU/eTh and eU/eK. Th and eTh/K images allowed the identification of metarenites and metaconglomerates bearing significative amounts of heavy minerals, thus revealing a new type of mineralization in the Serido Belt. Semi-quantitative scanning electron microscopy (SEM) analyses revealed up to 79.4% of ThO2 and 87.7% of REE in monazites; up to 99.2% of TiO2 in rutile and up to 1.81% of HfO2 in zircon. These results indicated the potential of the methodology employed in this work for the characterization of pegmatitic granites and pegmatites in the Borborema Pegmatitic Province (BPP) using low spatial resolution airborne geophysical data collected decades ago. The detailed study of the Galo Branco granite with ground gamma ray data and radiometric and ICP-MS laboratory analysis showed that this granite has U grades of 0.47 ppm to 7.8 ppm, Th between 0.1 ppm and 21.0 ppm and K between 2.00% e 5.24%. These concentrations are irregularly distributed suggesting mineralogical changes in contents and concentration of accessory minerals during magmatic crystallization and differentiation stages of this granite. The occurrence of pegmatites dikes intruding the quartzites to the south of the Galo Branco granite was revealed by the eUe/Th ratio since they are relatively enriched in uranium. / Doutorado / Geologia e Recursos Naturais / Doutor em Geociências
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Laboratorní spektroskopie pro vybrané druhy vegetace z krkonošské tundry / Laboratory spectroscopy for selected Krkonoše Mts. tundra vegetation speciesTomcová, Jana January 2019 (has links)
Laboratory spectroscopy for selected Krkonoše Mts. tundra vegetation species The diploma thesis is focused on testing the methodologies of measuring the reflectance of grasses from the tundra of Krkonoše Mountains (Nardus stricta, Molinia caerulea, Calamagrostis villosa). The spectoradiometer ASD FieldSpec 4 Wide-Res with added contact probe ASD Plant Probe is used for measurements. Since it is not common to measure such narrow leaves that do not cover the whole FOV, the thesis is looking for methodologies that are the most repeatable and influenced by a minimum of errors. Factors influencing the measurement results are also monitored. Furthermore, the differentiation of the studied species is observed based on their spectral properties. Based on the measured data the medians and standard deviations are calculated and compared among each other. An analysis of variance (ANOVA) is used to determine the bands where the influence of individual factors is more apparent and where the individual grasses are distinguishable. As the most suitable methodologies for measuring grasses depend on the grasses structures and properties, the best methodology is different for each of selected species. The two layer leaf measurement is most suitable for the Nardus stricta, the measurement of the abaxial sides of leaves fits...
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