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Land Use/Land Cover Classification From Satellite Remote Sensing Images Over Urban Areas in Sweden : An Investigative Multiclass, Multimodal and Spectral Transformation, Deep Learning Semantic Image Segmentation Study / Klassificering av markanvändning/marktäckning från satellit-fjärranalysbilder över urbana områden i Sverige : En undersökande multiklass, multimodal och spektral transformation, djupinlärningsstudie inom semantisk bildsegmenteringAidantausta, Oskar, Asman, Patrick January 2023 (has links)
Remote Sensing (RS) technology provides valuable information about Earth by enabling an overview of the planet from above, making it a much-needed resource for many applications. Given the abundance of RS data and continued urbanisation, there is a need for efficient approaches to leverage RS data and its unique characteristics for the assessment and management of urban areas. Consequently, employing Deep Learning (DL) for RS applications has attracted much attention over the past few years. In this thesis, novel datasets consisting of satellite RS images over urban areas in Sweden were compiled from Sentinel-2 multispectral, Sentinel-1 Synthetic Aperture Radar (SAR) and Urban Atlas 2018 Land Use/Land Cover (LULC) data. Then, DL was applied for multiband and multiclass semantic image segmentation of LULC. The contributions of complementary spectral, temporal and SAR data and spectral indices to LULC classification performance compared to using only Sentinel-2 data with red, green and blue spectral bands were investigated by implementing DL models based on the fully convolutional network-based architecture, U-Net, and performing data fusion. Promising results were achieved with 25 possible LULC classes. Furthermore, almost all DL models at an overall model level and all DL models at an individual class level for most LULC classes benefited from complementary satellite RS data with varying degrees of classification improvement. Additionally, practical knowledge and insights were gained from evaluating the results and are presented regarding satellite RS data characteristics and semantic segmentation of LULC in urban areas. The obtained results are helpful for practitioners and researchers applying or intending to apply DL for semantic segmentation of LULC in general and specifically in Swedish urban environments.
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Investigating the potential of hyperspectral remote sensing data for the analysis of urban imperviousnessLinden, Sebastian van der 19 May 2008 (has links)
Durch den Prozess der Urbanisierung verändert die Menschheit die Erdoberfläche in großem Ausmaß und auf unwiederbringliche Weise. Die optische Fernerkundung ist eine Art der Erdbeobachtung, die das Verständnis dieses dynamischen Prozesses und seiner Auswirkungen erweitern kann. Die vorliegende Arbeit untersucht, inwiefern hyperspektrale Daten Informationen über Versiegelung liefern können, die der integrierten Analyse urbaner Mensch-Umwelt-Beziehungen dienen. Hierzu wird die Verarbeitungskette von Vorverarbeitung der Rohdaten bis zur Erstellung referenzierter Karten zu Landbedeckung und Versiegelung am Beispiel von Hyperspectral Mapper Daten von Berlin ganzheitlich untersucht. Die traditionelle Verarbeitungskette wird mehrmals erweitert bzw. abgewandelt. So wird die radiometrische Vorverarbeitung um die Normalisierung von Helligkeitsgradienten erweitert, welche durch die direktionellen Reflexionseigenschaften urbaner Oberflächen entstehen. Die Klassifikation in fünf spektral komplexe Landnutzungsklassen wird mit Support Vector Maschinen ohne zusätzliche Merkmalsextraktion oder Differenzierung von Subklassen durchgeführt. Eine detaillierte Ergebnisvalidierung erfolgt mittels vielfältiger Referenzdaten. Es wird gezeigt, dass die Kartengenauigkeit von allen Verarbeitungsschritten abhängt: Support Vector Maschinen klassifizieren Hyperspektraldaten akkurat aber die Kartengenauigkeit wird durch die Georeferenzierung deutlich gemindert; die Versiegelungskartierung stellt die Situation am Boden gut dar, aber die Überdeckung versiegelter Flächen durch Bäume bedingt systematische Fehlschätzungen; eine Bildsegmentierung führt zu keiner Verbesserung der Klassifikationsergebnisse, bietet jedoch eine sinnvolle Möglichkeit zur effektiveren Prozessierung durch Datenkomprimierung. Auf diesem Weg ermöglicht die vorliegende Arbeit Rückschlüsse zur Verlässlichkeit von Datenprodukten, die eine Ausweitung fernerkundlicher Analysen in weniger gut dokumentierte urbane Räume voranbringt. / Urbanization is one of the most powerful and irreversible processes by which humans modify the Earth''s surface. Optical remote sensing is a main source of Earth observation products which help to better understand this dynamic process and its consequences. This work investigates the potential of airborne hyperspectral data to provide information on urban imperviousness that is needed for an integrated analysis of the coupled natural and human systems therein. For this purpose the complete processing workflow from preprocessing of the raw image to the generation of geocoded maps on land cover and impervious surface coverage is performed using Hyperspectral Mapper data acquired over Berlin, Germany. The traditional workflow for hyperspectral data is extended or modified at several points: a normalization of brightness gradients that are caused by directional reflectance properties of urban surfaces is included into radiometric preprocessing; support vector machines are used to classify five spectrally complex land cover classes without previous feature extraction or the definition of sub-classes. A detailed assessment of such maps is performed based on various reference products. Results show that the accuracy of derived maps depends on several steps within the processing workflow. For example, the support vector machine classification of hyperspectral data itself is accurate but geocoding without detailed terrain information introduces critical errors; impervious surface estimates correlate well with ground data but trees covering impervious surface below generally causes offsets; image segmentation does not enhance spectral classification accuracy of the spatially heterogeneous area but offers an interesting way of data compression and more time effective processing. Findings from this work help judging the reliability of data products and in doing so advance a possible extension of urban remote sensing approaches to areas where only little additional data exists.
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Determination of water body structures for small rivers using remote sensing dataKarrasch, Pierre, Henzen, Daniel, Hunger, Sebastian, Hörold, Max 29 August 2019 (has links)
The diversity of habitats in water bodies like rivers is characterised by the status of morphological and hydrological conditions. The good ecological status of water bodies is claimed in the EuropeanWater Framework Directive. For the assessment of this status the hydro-morphology is one of the most important supporting components for the classification of the ecological status of water bodies. Therefore the periodical monitoring is a mandatory measure in the scope of the European Water Framework Directive. Regarding the so called overview-method of the LAWA (German Working Group on water issues of the Federal States and the Federal Government represented by the Federal Environment Ministry) the use of remote sensing data and remote sensing methodologies becomes more important. Therefore remote sensing data on different scales (satellite, aerial photographs) as well as other topographic information (ATKIS) and a high resolution DTM are merged into an integrative process of analysis using remote sensing and GIS methodology. The analyses ared focused on two parameters. First, a detailed landuse classification based on LANDSAT satellite data is performed for whole catchment of a small river. The results show significant increase of urban areas close to the river. The second analyses deals with the determination of river curvature and introduces the use of a quasi-continously representation of the river. An additional challenge is the chosen study area of a low mountain range river. While large rivers are clear visible in remote sensing data, the usability and transformation of the well-established algorithms and work ows to small rivers need a further substantial research.
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"The Trees Act Not as Individuals"--Learning to See the Whole Picture in Biology Education and Remote Sensing ResearchGreenall, Rebeka A.F. 18 August 2023 (has links) (PDF)
To increase equity and inclusion for underserved and excluded Indigenous students, we must make efforts to mitigate the unique barriers they face. As their knowledge systems have been historically excluded and erased in Western science, we begin by reviewing the literature on the inclusion of Traditional Ecological Knowledge (TEK) in biology education and describe best practices. Next, to better understand how Native Hawaiian and other Pacific Islander (NHPI) students integrate into the scientific community, we used Social Influence Theory as a framework to measure NHPI student science identity, self-efficacy, alignment with science values, and belonging. We also investigated how students feel their ethnic and science identities interact. We found that NHPI students do not significantly differ from non-NHPI students in these measures of integration, and that NHPI students are varied in how they perceive their ethnic and science identities interact. Some students experience conflict between the two identities, while others view the two as having a strengthening relationship. Next, we describe a lesson plan created to include Hawaiian TEK in a biology class using best practices described in the literature. This is followed by an empirical study on how students were impacted by this lesson. We measured student integration into the science community using science identity, self-efficacy, alignment with science values, and belonging. We found no significant differences between NHPI and non-NHPI students. We also looked at student participation, and found that all students participated more on intervention days involving TEK and other ways of knowing than on non-intervention days. Finally, we describe qualitative findings on how students were impacted by the TEK interventions. We found students were predominantly positively impacted by the inclusion of TEK and discuss future adjustments that could be made using their recommendations. The last chapter describes how we used remote sensing to investigate land cover in a fenced and unfenced region of the Koʻolau Mountains on the island of Oahu. After mapping the biodiversity hotspot Management Unit of Koloa, we found that there is slighlty more bare ground, grass, and bare ground/low vegetation mix in fenced, and thereby ungulate-free areas, than those that were unfenced and had ungulates. Implications of these findings and suggestions for future research are discussed.
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Influences of Watershed Land Cover Pattern on Water Quality and Biotic Integrity of Coastal Plain Streams in Mississippi, USASchweizer, Peter E. 29 December 2008 (has links)
No description available.
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Exploiting the Spatial Information in High Resolution Satellite Data and Utilising Multi-Source Data for Tropical Mountain Forest and Land Cover Mapping / Verwertung der räumlichen Information in hochauflösenden Satellitendaten und Nutzung weiterer Geodaten zur Kartierung der Vegetationstypen in einem tropischen GebirgeGleitsmann, Anke 05 July 2005 (has links)
No description available.
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