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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

Snapshot imaging spectropolarimetry

Hagen, Nathan January 2007 (has links)
The research for this dissertation project began with the goal to construct a snapshot imaging spectropolarimeter forthe visible spectrum. The instrument integrates a channeled spectropolarimeter (CHSP) into a computed tomographicimaging spectrometer (CTIS), the result being an instrument that measures the complete spatially- andspectrally-resolved Stokes vectors of a scene. It is not the first of its kind, since a similar instrument has beenbuilt before for use in the short-wave infrared. However, that instrument encountered severe difficulties due tolimitations of available hardware. Visible spectrum work generally enjoys the best instrumentation available, providingan ideal place to attempt a proof-of-concept demonstration.The main body of the research is focused on finding ways to improve the CTIS measurement technique, especially in waysallowing it to integrate with channeled spectropolarimetry. The first effort is a careful analysis and reworking of thecalibration procedure for the instrument, followed by a survey and comparison of ideas for alternative CTIS designs.The second effort makes use of the new calibration approach to develop an alternative way of thinking about CTISreconstructions based on the geometry and physics of the instrument rather than on abstract matrix mathematics. Thisopens up ways to improve their accuracy and to achieve reconstructions at a much higher speed.Experimental results from the instrument illustrate the improvements obtained from using the new methods, showing itscurrent capabilities and limitations.
2

Computed Tomographic Imaging Spectrometry

Vandervlugt, Corrie Jean January 2011 (has links)
A Computed Tomographic Imaging Spectrometer (CTIS) is an imaging spectrometer which can acquire a hyper-spectral data set in a single snapshot (one focal plane array integration time) with no moving parts. A specially designed dispersing element, which separates light from the three-dimensional object cube into a grid of two-dimensional prismatic diffraction orders, is the key element in the instrument. The capabilities of the CTIS instrument can be improved by employing a more optimized grating design.There were two main goals to this research: (1) to design a novel CTIS disperser that will improve CTIS capabilities over the previous 5x5 disperser and (2) to integrate the new disperser into the CTIS and evaluate its performance compared to the 5x5 disperser. Six new disperser ideas were evaluated based on their performance in a number of computer simulations to determine the most optimal dispersion pattern. A new CTIS disperser incorporating a novel radial design pattern was developed and tested. Reconstruction results of various spatial and spectral targets are presented. Capabilities of the new CTIS instrument incorporating the radial grating are compared to the previous instrument employing a 5x5 disperser. While both dispersers perform similarly for point-source objects, the radial grating performs better than the previous disperser for extended sources.
3

Espectroscopia de refletância e de imageamento aplicadas ao monitoramento de solos expostos em instalações petrolíferas / Reflectance and imaging spectroscopy applied to monitor bare soil in oil facilities

Correa Pabón, Rosa Elvira, 1985 26 August 2018 (has links)
Orientador: Carlos Roberto de Souza Filho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-26T19:58:27Z (GMT). No. of bitstreams: 1 CorreaPabon_RosaElvira_D.pdf: 10125024 bytes, checksum: 73b222e9787711d668d1cc3b8a2845ba (MD5) Previous issue date: 2015 / Resumo: Essa pesquisa compreende a aplicação de técnicas de espectroscopia de refletância e imageamento hiperespectral aeroportado visando o aprimoramento de métodos e sistemas de monitoramento de solos expostos à vazamentos de hidrocarbonetos (HCs), em instalações petrolíferas. O trabalho compreendeu um experimento em ambiente de laboratório, onde contaminações controladas foram realizadas buscando-se simular, em escala reduzida, solos impactados por vazamentos de HCs. Os principais objetivos do experimento foram os seguintes: (i) caracterizar as assinaturas espectrais dos solos impregnados com HCs, em diferentes proporções, no intervalo do espectro visível e infravermelho (350 ¿ 2500 nm); (ii) descrever as principais feições de absorção espectral diagnósticas da presença do HC; (iii) estabelecer os limites de detecção do HC na mistura; (iv) gerar modelos matemáticos de simples aplicação, que permitam estimar o tipo e volume de HCs envolvido na contaminação. Considerando a base gerada nas investigações experimentais, em um segundo passo, técnicas digitais de extração de informações espectrais foram aplicadas a um conjunto de imagens hiperespectrais adquiridas sobre instalações petrolíferas e áreas experimentais de vazamentos de HCs líquidos em escala real. Como resultado, foi possível identificar a distribuição espacial de solos e outros alvos potencialmente contaminados nessas áreas, cujos principais focos foram comprovados no campo. O estudo sugere o grande potencial de aplicação destas tecnologias ultraespectrais e hiperespectrais no monitoramento de solos em torno das linhas de transporte de petróleo e de refinarias, o que pode contribuir para aquilatar a segurança e desempenho operacional de dutos de transporte e armazenamento de HCs na indústria do petróleo / Abstract: This research involves the application of reflectance and imaging spectroscopy techniques to improve methods and systems to monitor bare soils contaminated by hydrocarbon (HC) leaks in petroleum refinaries and pipelines. The study involves an experiment, conducted under laboratory conditions; where controlled contaminations were made aiming to simulate, in a small scale, soils contaminated with hydrocarbon leaks. The main objectives of the experiment are the following: (i) to characterize the spectral signature of contaminated soils, with several proportions of HCs, within visible and infrared wavelengths (350 ¿ 2500 nm); (ii) to describe the main, diagnostic absorption bands linked to the presence of HCs, (iii) to establish concentration limits for the detection of HCs in substrate mixtures; (iv) to generate simple models to estimate the HC type and impregnation level involved in the contamination. The comprehensive spectral libraries yielded during the laboratory experiments were used, in a second step, as an input for the application of digital information extraction techniques to hyperspectral image datasets acquired on real petroleum facilities and field experimental areas of liquid HC leaks. Given such representative scenarios, it was possible to identify the spatial distribution of soils and other potentially contaminated targets in these areas, which were verified further in the field and corresponded to sites with leaks. The study suggests the great potential for intelligent use of ultraspectral and hyperspectral technologies for monitoring soils around pipelines and refineries, adding to the safety and operational performance of oil pipelines and storage in the petroleum industry / Doutorado / Geologia e Recursos Naturais / Doutora em Ciências
4

Road Condition Mapping by Integration of Laser Scanning, RGB Imaging and Spectrometry

Miraliakbari, Alvand 16 August 2017 (has links)
Roads are important infrastructure and are primary means of transportation. Control and maintenance of roads are substantial as the pavement surface deforms and deteriorates due to heavy load and influences of weather. Acquiring detailed information about the pavement condition is a prerequisite for proper planning of road pavement maintenance and rehabilitation. Many companies detect and localize the road pavement distresses manually, either by on-site inspection or by digitizing laser data and imagery captured by mobile mapping. The automation of road condition mapping using laser data and colour images is a challenge. Beyond that, the mapping of material properties of the road pavement surface with spectrometers has not yet been investigated. This study aims at automatic mapping of road surface condition including distress and material properties by integrating laser scanning, RGB imaging and spectrometry. All recorded data are geo-referenced by means of GNSS/ INS. Methods are developed for pavement distress detection that cope with a variety of different weather and asphalt conditions. Further objective is to analyse and map the material properties of the pavement surface using spectrometry data. No standard test data sets are available for benchmarking developments on road condition mapping. Therefore, all data have been recorded with a mobile mapping van which is set up for the purpose of this research. The concept for detecting and localizing the four main pavement distresses, i.e. ruts, potholes, cracks and patches is the following: ruts and potholes are detected using laser scanning data, cracks and patches using RGB images. For each of these pavement distresses, two or more methods are developed, implemented, compared to each other and evaluated to identify the most successful method. With respect to the material characteristics, spectrometer data of road sections are classified to indicate pavement quality. As a spectrometer registers almost a reflectivity curve in VIS, NIR and SWIR wavelength, indication of aging can be derived. After detection and localization of the pavement distresses and pavement quality classes, the road condition map is generated by overlaying all distresses and quality classes. As a preparatory step for rut and pothole detection, the road surface is extracted from mobile laser scanning data based on a height jump criterion. For the investigation on rut detection, all scanlines are processed. With an approach based on iterative 1D polynomial fitting, ruts are successfully detected. For streets with the width of 6 m to 10 m, a 6th order polynomial is found to be most suitable. By 1D cross-correlation, the centre of the rut is localized. An alternative method using local curvature shows a high sensitivity to the shape and width of a rut and is less successful. For pothole detection, the approach based on polynomial fitting generalized to two dimensions. As an alternative, a procedure using geodesic morphological reconstruction is investigated. Bivariate polynomial fitting encounters problems with overshoot at the boundary of the regions. The detection is very successful using geodesic morphology. For the detection of pavement cracks, three methods using rotation invariant kernels are investigated. Line Filter, High-pass Filter and Modified Local Binary Pattern kernels are implemented. A conceptual aspect of the procedure is to achieve a high degree of completeness. The most successful variant is the Line Filter for which the highest degree of completeness of 81.2 % is achieved. Two texture measures, the gradient magnitude and the local standard deviation are employed to detect pavement patches. As patches may differ with respect to homogeneity and may not always have a dark border with the intact pavement surface, the method using the local standard deviation is more suitable for detecting the patches. Linear discriminant analysis is utilized for asphalt pavement quality analysis and classification. Road pavement sections of ca. 4 m length are classified into two classes, namely: “Good” and “Bad” with the overall accuracy of 77.6 %. The experimental investigations show that the developed methods for automatic distress detection are very successful. By 1D polynomial fitting on laser scanlines, ruts are detected. In addition to ruts also pavement depressions like shoving can be revealed. The extraction of potholes is less demanding. As potholes appear relatively rare in the road networks of a city, the road segments which are affected by potholes are selected interactively. While crack detection by Line Filter works very well, the patch detection is more challenging as patches sometimes look very similar to the intact surface. The spectral classification of pavement sections contributes to road condition mapping as it gives hints on aging of the road pavement. / Straßen bilden die primären Transportwege für Personen und Güter und sind damit ein wichtiger Bestandteil der Infrastruktur. Der Aufwand für Instandhaltung und Wartung der Straßen ist erheblich, da sich die Fahrbahnoberfläche verformt und durch starke Belastung und Wettereinflüsse verschlechtert. Die Erfassung detaillierter Informationen über den Fahrbahnzustand ist Voraussetzung für eine sachgemäße Planung der Fahrbahnsanierung und -rehabilitation. Viele Unternehmen detektieren und lokalisieren die Fahrbahnschäden manuell entweder durch Vor-Ort-Inspektion oder durch Digitalisierung von Laserdaten und Bildern aus mobiler Datenerfassung. Eine Automatisierung der Straßenkartierung mit Laserdaten und Farbbildern steht noch in den Anfängen. Zudem werden bisher noch nicht die Alterungszustände der Asphaltdecke mit Hilfe der Spektrometrie bewertet. Diese Studie zielt auf den automatischen Prozess der Straßenzustandskartierung einschließlich der Straßenschäden und der Materialeigenschaften durch Integration von Laserscanning, RGB-Bilderfassung und Spektrometrie ab. Alle aufgezeichneten Daten werden mit GNSS / INS georeferenziert. Es werden Methoden für die Erkennung von Straßenschäden entwickelt, die sich an unterschiedliche Datenquellen bei unterschiedlichem Wetter- und Asphaltzustand anpassen können. Ein weiteres Ziel ist es, die Materialeigenschaften der Fahrbahnoberfläche mittels Spektrometrie-Daten zu analysieren und abzubilden. Derzeit gibt es keine standardisierten Testdatensätze für die Evaluierung von Verfahren zur Straßenzustandsbeschreibung. Deswegen wurden alle Daten, die in dieser Studie Verwendung finden, mit einem eigens für diesen Forschungszweck konfigurierten Messfahrzeug aufgezeichnet. Das Konzept für die Detektion und Lokalisierung der wichtigsten vier Arten von Straßenschäden, nämlich Spurrillen, Schlaglöcher, Risse und Flickstellen ist das folgende: Spurrillen und Schlaglöcher werden aus Laserdaten extrahiert, Risse und Flickstellen aus RGB- Bildern. Für jede dieser Straßenschäden werden mindestens zwei Methoden entwickelt, implementiert, miteinander verglichen und evaluiert um festzustellen, welche Methode die erfolgreichste ist. Im Hinblick auf die Materialeigenschaften werden Spektrometriedaten der Straßenabschnitte klassifiziert, um die Qualität des Straßenbelages zu bewerten. Da ein Spektrometer nahezu eine kontinuierliche Reflektivitätskurve im VIS-, NIR- und SWIR-Wellenlängenbereich aufzeichnet, können Merkmale der Asphaltalterung abgeleitet werden. Nach der Detektion und Lokalisierung der Straßenschäden und der Qualitätsklasse des Straßenbelages wird der übergreifende Straßenzustand mit Hilfe von Durchschlagsregeln als Kombination aller Zustandswerte und Qualitätsklassen ermittelt. In einem vorbereitenden Schritt für die Spurrillen- und Schlaglocherkennung wird die Straßenoberfläche aus mobilen Laserscanning-Daten basierend auf einem Höhensprung-Kriterium extrahiert. Für die Untersuchung zur Spurrillen-Erkennung werden alle Scanlinien verarbeitet. Mit einem Ansatz, der auf iterativer 1D-Polynomanpassung basiert, werden Spurrillen erfolgreich erkannt. Für eine Straßenbreite von 8-10m erweist sich ein Polynom sechsten Grades als am besten geeignet. Durch 1D-Kreuzkorrelation wird die Mitte der Spurrille erkannt. Eine alternative Methode, die die lokale Krümmung des Querprofils benutzt, erweist sich als empfindlich gegenüber Form und Breite einer Spurrille und ist weniger erfolgreich. Zur Schlaglocherkennung wird der Ansatz, der auf Polynomanpassung basiert, auf zwei Dimensionen verallgemeinert. Als Alternative wird eine Methode untersucht, die auf der Geodätischen Morphologischen Rekonstruktion beruht. Bivariate Polynomanpassung führt zu Überschwingen an den Rändern der Regionen. Die Detektion mit Hilfe der Geodätischen Morphologischen Rekonstruktion ist dagegen sehr erfolgreich. Zur Risserkennung werden drei Methoden untersucht, die rotationsinvariante Kerne verwenden. Linienfilter, Hochpassfilter und Lokale Binäre Muster werden implementiert. Ein Ziel des Konzeptes zur Risserkennung ist es, eine hohe Vollständigkeit zu erreichen. Die erfolgreichste Variante ist das Linienfilter, für das mit 81,2 % der höchste Grad an Vollständigkeit erzielt werden konnte. Zwei Texturmaße, nämlich der Betrag des Grauwert-Gradienten und die lokale Standardabweichung werden verwendet, um Flickstellen zu entdecken. Da Flickstellen hinsichtlich der Homogenität variieren können und nicht immer eine dunkle Grenze mit dem intakten Straßenbelag aufweisen, ist diejenige Methode, welche die lokale Standardabweichung benutzt, besser zur Erkennung von Flickstellen geeignet. Lineare Diskriminanzanalyse wird zur Analyse der Asphaltqualität und zur Klassifikation benutzt. Straßenabschnitte von ca. 4m Länge werden zwei Klassen („Gut“ und „Schlecht“) mit einer gesamten Accuracy von 77,6 % zugeordnet. Die experimentellen Untersuchungen zeigen, dass die entwickelten Methoden für die automatische Entdeckung von Straßenschäden sehr erfolgreich sind. Durch 1D Polynomanpassung an Laser-Scanlinien werden Spurrillen entdeckt. Zusätzlich zu Spurrillen werden auch Unebenheiten des Straßenbelages wie Aufschiebungen detektiert. Die Extraktion von Schlaglöchern ist weniger anspruchsvoll. Da Schlaglöcher relativ selten in den Straßennetzen von Städten auftreten, werden die Straßenabschnitte mit Schlaglöchern interaktiv ausgewählt. Während die Rissdetektion mit Linienfiltern sehr gut funktioniert, ist die Erkennung von Flickstellen eine größere Herausforderung, da Flickstellen manchmal der intakten Straßenoberfläche sehr ähnlich sehen. Die spektrale Klassifizierung der Straßenabschnitte trägt zur Straßenzustandsbewertung bei, indem sie Hinweise auf den Alterungszustand des Straßenbelages liefert.
5

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 Brasil

Silva, 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
6

Quantifying urban land cover by means of machine learning and imaging spectrometer data at multiple spatial scales

Okujeni, Akpona 15 December 2014 (has links)
Das weltweite Ausmaß der Urbanisierung zählt zu den großen ökologischen Herausforderungen des 21. Jahrhunderts. Die Fernerkundung bietet die Möglichkeit das Verständnis dieses Prozesses und seiner Auswirkungen zu erweitern. Der Fokus dieser Arbeit lag in der Quantifizierung der städtischen Landbedeckung mittels Maschinellen Lernens und räumlich unterschiedlich aufgelöster Hyperspektraldaten. Untersuchungen berücksichtigten innovative methodische Entwicklungen und neue Möglichkeiten, die durch die bevorstehende Satellitenmission EnMAP geschaffen werden. Auf Basis von Bilder des flugzeugestützten HyMap Sensors mit Auflösungen von 3,6 m und 9 m sowie simulierten EnMAP-Daten mit einer Auflösung von 30 m wurde eine Kartierung entlang des Stadt-Umland-Gradienten Berlins durchgeführt. Im ersten Teil der Arbeit wurde die Kombination von Support Vektor Regression mit synthetischen Trainingsdaten für die Subpixelkartierung eingeführt. Ergebnisse zeigen, dass sich der Ansatz gut zur Quantifizierung thematisch relevanter und spektral komplexer Oberflächenarten eignet, dass er verbesserte Ergebnisse gegenüber weiteren Subpixelverfahren erzielt, und sich als universell einsetzbar hinsichtlich der räumlichen Auflösung erweist. Im zweiten Teil der Arbeit wurde der Wert zukünftiger EnMAP-Daten für die städtische Fernerkundung abgeschätzt. Detaillierte Untersuchungen unterstreichen deren Eignung für eine verbesserte und erweiterte Beschreibung der Stadt nach dem bewährten Vegetation-Impervious-Soil-Schema. Analysen der Möglichkeiten und Grenzen zeigen sowohl Nachteile durch die höhere Anzahl von Mischpixel im Vergleich zu hyperspektralen Flugzeugdaten als auch Vorteile aufgrund der verbesserten Differenzierung städtischer Materialien im Vergleich zu multispektralen Daten. Insgesamt veranschaulicht diese Arbeit, dass die Kombination von hyperspektraler Satellitenbildfernerkundung mit Methoden des Maschinellen Lernens eine neue Qualität in die städtische Fernerkundung bringen kann. / The global dimension of urbanization constitutes a great environmental challenge for the 21st century. Remote sensing is a valuable Earth observation tool, which helps to better understand this process and its ecological implications. The focus of this work was to quantify urban land cover by means of machine learning and imaging spectrometer data at multiple spatial scales. Experiments considered innovative methodological developments and novel opportunities in urban research that will be created by the upcoming hyperspectral satellite mission EnMAP. Airborne HyMap data at 3.6 m and 9 m resolution and simulated EnMAP data at 30 m resolution were used to map land cover along an urban-rural gradient of Berlin. In the first part of this work, the combination of support vector regression with synthetically mixed training data was introduced as sub-pixel mapping technique. Results demonstrate that the approach performs well in quantifying thematically meaningful yet spectrally challenging surface types. The method proves to be both superior to other sub-pixel mapping approaches and universally applicable with respect to changes in spatial scales. In the second part of this work, the value of future EnMAP data for urban remote sensing was evaluated. Detailed explorations on simulated data demonstrate their suitability for improving and extending the approved vegetation-impervious-soil mapping scheme. Comprehensive analyses of benefits and limitations of EnMAP data reveal both challenges caused by the high numbers of mixed pixels, when compared to hyperspectral airborne imagery, and improvements due to the greater material discrimination capability when compared to multispectral spaceborne imagery. In summary, findings demonstrate how combining spaceborne imaging spectrometry and machine learning techniques could introduce a new quality to the field of urban remote sensing.

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