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Geographic characteristics of circulation patterns and features in the South Atlantic and South Indian Oceans using satellite remote sensingMeeuwis, June Myrtle 10 April 2014 (has links)
D.Litt. et Phil. / Please refer to full text to view abstract
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Using remote sensing and aerial archaeology to detect pit house features in Worldview-2 satellite imagery. : A case study for the Bridge River archaeological pit house village in south-central British Columbia, Canada.Cooke, Sarah January 2017 (has links)
It is well known that archaeological sites are important sources for understanding past human activity. However, those sites yet to be identified and further investigated are under a great risk of being lost or damaged before their archaeological significance is fully recognized. The aim of this research was to analyze the potential use of remote sensing and aerial archaeology techniques integrated within a geographic information system (GIS) for the purpose of remotely studying pit house archaeology. As pit house archaeological sites in North America have rarely been studied with a focus in remote sensing, this study intended to identify these features by processing very high resolution satellite imagery and assessing how accurately the identified features could be automatically mapped with the use of a GIS. A Worldview-2 satellite image of the Bridge River pit house village in Lillooet, south-central British Columbia, was processed within ArcGIS 10.1 (ESRI), ERDAS Imagine 2011 (Intergraph) and eCognition Developer 8 (Trimble) to identify spatial and spectral queues representing the pit house features. The study outlined three different feature extraction methods (GIS-based, pixel-based and object-based) and evaluated which method presented the best results. Though all three methods produced similar results, the potential for performing object-based feature extraction for research in aerial archaeology proved to be more advantageous than the other two extraction methods tested.
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Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife RefugeBlackmore, Debra Sue 30 August 2016 (has links)
This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments.
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On-Road Remote Sensing of Motor Vehicle Emissions: Associations between Exhaust Pollutant Levels and Vehicle Parameters for Arizona, California, Colorado, Illinois, Texas, and UtahDohanich, Francis Albert 05 1900 (has links)
On-road remote sensing has the ability to operate in real-time, and under real world conditions, making it an ideal candidate for detecting gross polluters on major freeways and thoroughfares. In this study, remote sensing was employed to detect carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxide (NO). On-road remote sensing data taken from measurements performed in six states, (Arizona, California, Colorado, Illinois, Texas, and Utah) were cleaned and analyzed. Data mining and exploration were first undertaken in order to search for relationships among variables such as make, year, engine type, vehicle weight, and location. Descriptive statistics were obtained for the three pollutants of interest. The data were found to have non-normal distributions. Applied transformations were ineffective, and nonparametric tests were applied. Due to the extremely large sample size of the dataset (508,617 records), nonparametric tests resulted in "p" values that demonstrated "significance." The general linear model was selected due to its ability to handle data with non-normal distributions. The general linear model was run on each pollutant with output producing descriptive statistics, profile plots, between-subjects effects, and estimated marginal means. Due to insufficient data within certain cells, results were not obtained for gross vehicle weight and engine type. The "year" variable was not directly analyzed in the GLM because "year" was employed in a weighted least squares transformation. "Year" was found to be a source of heteroscedasticity; and therefore, the basis of a least-squares transformation. Grouped-years were analyzed using medians, and the results were displayed graphically. Based on the GLM results and descriptives, Japanese vehicles typically had the lowest CO, HC, and NO emissions, while American vehicles ranked high for the three. Illinois, ranked lowest for CO, while Texas ranked highest. Illinois and Colorado were lowest for HC emissions, while Utah and California were highest. For NO, Colorado ranked highest with Texas and Arizona, lowest.
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CLASSIFYING DOMINANT PARKLAND SPECIES IN A WEST AFRICAN AGROFORESTRY LANDSCAPE USING PLEIADES SATELLITE IMAGERYLunn, Simon January 2020 (has links)
As we move towards a digital based society, technology continues to improve. It is important to take advantage of this to inform and facilitate our sustainable development goals in the most cost-effective and time efficient manner. By utilising the best available technologies, not only can time savings be achieved, but scope of works can be dramatically increased, particularly with ecological data collection. This study will focus on collecting ecological data (tree species) using developing modern technologies (satellites) with the aim of reaching classification accuracies comparable with ground truthed (real life) records. The study area is in central Burkina Faso approximately 30km south of the capital and is generally described as an agroforestry parklands area. The region suffers greatly from poverty and many people are heavily dependent on the agricultural sector and subsistence farming. As these agroforestry parklands are so critical to many people’s livelihoods, it is important to assess the natural resources available within them to provide the best food security management for the people. Tree species locations were overlayed on two satellite images acquired during different stages of the annual growing periods in the agroforestry parklands of the study area. From these images, segmentation of individual tree crowns was done manually and used as the reference data for an object-based classification model, which were assessed for the classification accuracies that can be achieved. Three satellite image scenarios were assessed for classification accuracy, including two single image scenarios and a multi-imagery dataset combining both images. Results indicate that combined images perform the best in terms of overall classification accuracies, closely followed by the end of the wet season growing period. The image acquisition from the end of the dry season was quite poor in comparison, having an overall classification accuracy more than 10% lower than the other scenarios. Of the focus species assessed in this study, Azadirachta Indica was the clear loser in terms of the number of correctly classified individuals from each model scenario. All other focus species were relatively well classified achieving close to or above 60% accuracies in the multi-imagery classification scenario.
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Identification of urban surface materials using high-resolution hyperspectral aerial imageryParanjape, Meghana 07 1900 (has links)
La connaissance des matériaux de surface est essentielle pour l’aménagement et la gestion des
villes. Avec les avancées en télédétection, particulièrement en imagerie de haute résolution spatiale
et spectrale, l’identification et la cartographie détaillée des matériaux de surface en milieu urbain
sont maintenant envisageables. Les signatures spectrales décrivent les interactions entre les objets
au sol et le rayonnement solaire, et elles sont supposées uniques pour chaque type de matériau de
surface.
Dans ce projet de recherche nous avons utilisé des images hyperspectrales aériennes du capteur
CASI, avec une résolution de 1 m2 et 96 bandes contigües entre 380nm et 1040nm. Ces images
couvrant l’île de Montréal (QC, Canada), acquises en 2016, ont été analysées pour identifier les
matériaux de surfaces.
Pour atteindre ces objectifs, notre méthode d’analyse est fondée sur la comparaison des signatures
spectrales d’un pixel quelconque à celles des objets typiques contenues dans des bibliothèques
spectrales (matériaux inertes et végétation). Pour mesurer la correspondance entre la signature
spectrale d’un objet et la signature spectrale de référence nous avons utilisé deux métriques. La
première métrique tient compte de la forme d’une signature spectrale et la seconde, de la différence
des valeurs de réflectance entre la signature spectrale observée et celle de référence. Un
classificateur flou utilisant ces deux métriques est alors appliqué afin de reconnaître le type de
matériau de surface sur la base du pixel. Des signatures spectrales typiques ont été extraites des
deux librairies spectrales (ASTER et HYPERCUBE). Des signatures spectrales des objets typiques
à Montréal mesurées sur le terrain (spectroradiomètre ASD) ont été aussi utilisées comme
références.
Trois grandes catégories de matériaux ont été identifiées dans les images pour faciliter la
comparaison entre les classifications par source de références spectrales : l’asphalte, le béton et la
végétation. La classification utilisant ASTER comme bibliothèque de référence a eu le plus grand
taux de réussite avec 92%, suivi par ASD à 88% et finalement HYPERCUBE avec 80%. Nous
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n’avons pas trouvé de différences significatives entre les trois résultats, ce qui indique que la
classification est indépendante de la source des signatures spectrales de référence. / Knowledge of surface cover materials is crucial for urban planning and management. With
advances in remote sensing, especially in high spatial and spectral resolution imagery, the
identification and detailed mapping of surface materials in urban areas based on spectral signatures
are now feasible. Spectral signatures describe the interactions between ground objects and solar
radiation and are assumed unique for each type of material.
In this research, we use airborne CASI images with 1 m2 spatial resolution, with 96 contiguous
bands in a spectral range between 367 nm and 1044 nm. These images covering the island of
Montreal (Quebec, Canada), obtained in 2016, were analyzed to identify urban surface materials.
The objectives of the project were first to find a correspondence between the physical and chemical
characteristic of typical surface materials, present in the Montreal scenes, and the spectral
signatures within the images. Second, to develop a sound methodology for identifying these
surface materials in urban landscapes.
To reach these objectives, our method of analysis is based on a comparison of pixel spectral
signatures to those contained in a reference spectral library that describe typical surface covering
materials (inert materials and vegetation). Two metrics were used in order to measure the
correspondence of pixel spectral signatures and reference spectral signature. The first metric
considers the shape of a spectral signature and the second the difference of reflectance values
between the observed and reference spectral signature. A fuzzy classifier using these two metrics
is then applied to recognize the type of material on a pixel basis. Typical spectral signatures were
extracted from two spectral libraries (ASTER and HYPERCUBE). Spectral signatures of typical
objects in Montreal measured on the ground (ASD spectroradiometer) were also used as reference
spectra. Three general types of surface materials (asphalt, concrete, and vegetation) were used to
ease the comparison between classifications using these spectral libraries. The classification using
ASTER as a reference library had the highest success rate reaching 92%, followed by the field
spectra at 88%, and finally with HYPERCUBE at 80%. There were no significant differences in
the classification results indicating that the methodology works independently of the source of
reference spectral signatures.
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Assessing Management of Nicaragua’s Caribbean Region Protected Areas Using Remote Sensing: The Indio Maíz Biological ReserveMuñoz Gamboa, Paola Sofía 10 September 2021 (has links)
No description available.
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Identification of alkaline fens using convolutional neural networks and multispectral satellite imageryJernberg, John January 2021 (has links)
The alkaline fen is a particularly valuable type of wetland with unique characteristics.Due to anthropogenic risk factors and the sensitive nature of the fens, protection is highlyprioritized with identification and mapping of current locations being important parts ofthis process. To accomplish this in a cost effective manner for large areas, remote sensingmethods using satellite images might be very effective. Following the rapid developmentin computer vision, deep learning using convolutional neural networks (CNN) is thecurrent state of the art for satellite image classification. Accordingly, this study evaluatesthe combination of different CNN architectures and multispectral Sentinel 2 satelliteimages for identification of alkaline fens using semantic segmentation. The implementedmodels are different variations of the proven U-net network design. In addition, a RandomForest classifier was trained for baseline comparison. The best result was produced bya spatial attention U-net with a IoU-score of 0.31 for the alkaline fen class and a meanIoU-score of 0.61. These findings suggest that identification of alkaline fens is possiblewith the current method even with a small dataset. However, an optimal solution tothis task may require deeper research. The results also further establish deep learningto be the superior choice over traditional machine learning algorithms for satellite imageclassification.
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Algorithm Performance on the Estimation of CDOM and DOC in the North Slopes of AlaskaWeisenbach, Monica 20 October 2021 (has links)
Use of satellite imagery makes environmental monitoring easy and convenient with little of the logistics involved in planning sampling campaigns. Colored dissolved organic matter (CDOM) is an important component to track as a proxy for the large pool of dissolved organic carbon (DOC). In a world contending with the looming issue of global climate change, the ability to investigate the carbon cycle of inland to coastal environments allows for examination of the magnitude of carbon flowing through the system and potential changes over years. The Arctic region is a critical area for climate change impacts but is a difficult landscape for sampling implementation and is thus an excellent target for satellite monitoring. This thesis focuses on the North Slopes region of Alaska to take advantage of the Toolik Lake monitoring site. Landsat 8 imagery has the appropriate spatial, spectral, and temporal resolutions for use in inland water and coastal environments. There are numerous developed algorithms for CDOM estimations, but many algorithms are designed for specific regions. A special challenge in inland environments is the bottom reflectance contribution to the outgoing light signal. An algorithm designed specifically for optically-shallow water environments (SBOP) was tested against two algorithms designed for optically-deep water environments (QAA-CDOM, K05). The relationship between CDOM and DOC was also investigated and used as further validation for algorithm performance. The SBOP algorithm shows promise iv alongside QAA-CDOM at estimating CDOM absorption, but the number of validation point makes pinpointing one algorithm difficult. All algorithms performed well at estimating DOC concentrations.
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Assessment of the impacts of selected Limpopo Province Dams on their downstream river ecosystems using remote sensing techniquesMokgoebo, Matjutla John 10 December 2013 (has links)
MEnv.Sc / Department of Geography and Geo-Information Sciences
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