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1

Nesbit, Paul R. "Uninhabited Aerial Vehicles and Structure from Motion| A fresh approach to photogrammetry." Thesis, California State University, Long Beach, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1526938.

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<p> Three-dimensional mapping and modeling can contribute to knowledge about the real world. Techniques are largely driven by available technology and typically involve expensive equipment and expert skill. Recent advances have led to low-cost remotely sensed data collection and generation of 3D terrain models using Uninhabited Aerial Vehicles (UAV) and Structure from Motion (SfM) processing software. This research presents a low-cost alternative to 3D mapping by pairing UAV collection methods with three SfM processing techniques. Surface models are generated from the same image set captured from a low-cost UAV coupled with a digital camera. Accuracy of resulting models identifies strengths and weaknesses of each technique. Analysis of different slope ranges investigates the divide at which surfaces generated become less reliable. This research provides a deeper understanding of the strengths and limitations of emerging technologies used together in a fresh approach to photogrammetry.</p>
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2

He, Juan Xia. "An ontology-based methodology for geospatial data integration." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28710.

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Data semantic and schematic heterogeneity is a major obstacle to the reuse and sharing of geospatial data. This research focuses on developing an ontology-based methodology to logically integrate heterogeneous geographic data in a cross-border context Three main obstacles hindering data integration are semantic, schematic, and syntactic heterogeneity. Approaches to overcome these obstacles in previous research are reviewed. Among the different approaches, an ontology-based approach is selected for horizontal geospatial data integration in the context of cross-border applications. The integration methodology includes the extraction of application schemas and application ontologies, ontology integration, the creation of a reference model (or ontologies), schema matching and integration, and the creation of usable integrated datasets. The methodology is conceptual and integrates geospatial data based on the semantic content and so is not tied to specific data formats, geometric representations, or feature locations. In order to facilitate the integration procedure, four semantic relationships are used: refer-to, semantic equivalence, semantic generalization, and semantic aggregation. A hybrid ontology approach is employed in order to facilitate the addition of new geospatial data sources to the integration process. As such, three levels of ontologies are developed and illustrated within a MS ACCESS database: application, domain, and a reference model. Furthermore, a working integration prototype is designed to facilitate the integration of geospatial data in the North American context given the semantic and schema heterogeneities in international Canadian-US geospatial datasets. The methodology and prototype provide users with the ability to freely query and retrieve data without knowledge of the heterogeneous data ontologies and schemas. This is illustrated via a case study identifying critical infrastructure around the Ambassador Bridge international border crossing. The methodology and prototype are compared and evaluated with other GDI approaches and by criteria introduced by Buccella et al. (2009). Specific challenges unique to GDI were uncovered and include geographic discrepancies, scale compatibility and temporal issues.
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3

Gwenzi, David. "Lidar remote sensing of savanna biophysical attributes." Thesis, Colorado State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3720536.

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<p> Although savanna ecosystems cover approximately 20 % of the terrestrial land surface and can have productivity equal to some closed forests, their role in the global carbon cycle is poorly understood. This study explored the applicability of a past spaceborne Lidar mission and the potential of future missions to estimate canopy height and carbon storage in these biomes. </p><p> The research used data from two Oak savannas in California, USA: the Tejon Ranch Conservancy in Kern County and the Tonzi Ranch in Santa Clara County. In the first paper we used non-parametric regression techniques to estimate canopy height from waveform parameters derived from the Ice Cloud and land Elevation Satellite&rsquo;s Geoscience Laser Altimeter System (ICESat-GLAS) data. Merely adopting the methods derived for forests did not produce adequate results but the modeling was significantly improved by incorporating canopy cover information and interaction terms to address the high structural heterogeneity inherent to savannas. Paper 2 explored the relationship between canopy height and aboveground biomass. To accomplish this we developed generalized models using the classical least squares regression modeling approach to relate canopy height to above ground woody biomass and then employed Hierarchical Bayesian Analysis (HBA) to explore the implications of using generalized instead of species composition-specific models. Models that incorporated canopy cover proxies performed better than those that did not. Although the model parameters indicated interspecific variability, the distribution of the posterior densities of the differences between composition level and global level parameter values showed a high support for the use of global parameters, suggesting that these canopy height-biomass models are universally (large scale) applicable. </p><p> As the spatial coverage of spaceborne lidar will remain limited for the immediate future, our objective in paper 3 was to explore the best means of extrapolating plot level biomass into wall-to-wall maps that provide more ecological information. We evaluated the utility of three spatial modeling approaches to address this problem: deterministic methods, geostatistical methods and an image segmentation approach. Overall, the mean pixel biomass estimated by the 3 approaches did not differ significantly but the output maps showed marked differences in the estimation precision and ability of each model to mimic the primary variable&rsquo;s trend across the landscape. The results emphasized the need for future satellite lidar missions to consider increasing the sampling intensity across track so that biomass observations are made and characterized at the scale at which they vary. </p><p> We used data from the Multiple Altimeter Beam Experimental Lidar (MABEL), an airborne photon counting lidar sensor developed by NASA Goddard to simulate ICESat-2 data. We segmented each transect into different block sizes and calculated canopy top and mean ground elevation based on the structure of the histogram of the block&rsquo;s aggregated photons. Our algorithm was able to compute canopy height and generate visually meaningful vegetation profiles at MABEL&rsquo;s signal and noise levels but a simulation of the expected performance of ICESat-2 by adjusting MABEL data's detected number of signal and noise photons to that predicted using ATLAS instrument model design cases indicated that signal photons will be substantially lower. The lower data resolution reduces canopy height estimation precision especially in areas of low density vegetation cover. </p><p> Given the clear difficulties in processing simulated ATLAS data, it appears unlikely that it will provide the kind of data required for mapping of the biophysical properties of savanna vegetation. Rather, resources are better concentrated on preparing for the Global Ecosystem Dynamics Investigation (GEDI) mission, a waveform lidar mission scheduled to launch by the end of this decade. In addition to the full waveform technique, GEDI will collect data from 25 m diameter contiguous footprints with a high across track density, a requirement that we identified as critically necessary in paper 3. (Abstract shortened by UMI.)</p>
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4

Lindsey, Eric Ostrom. "Fault properties, rheology and interseismic deformation in Southern California from high-precision space geodesy." Thesis, University of California, San Diego, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3721663.

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<p> This dissertation presents the collection and processing of dense high-precision geode- tic data across major faults throughout Southern California. The results are used to inform numerical models of the long-term slip rate and interseismic behavior of these faults, as well as their frictional and rheological properties at shallow depths. The data include campaign surveys of dense networks of GPS monuments crossing the faults, and Interferometric Synthetic Aperture Radar (InSAR) observations from ENVISAT. Using a Bayesian framework, we first assess to what extent these data constrain relative fault slip rates on the San Andreas and San Jacinto faults, and show that the inferred parameters depend critically on the assumed fault geometry. We next look in detail at near-field observations of strain across the San Jacinto fault, and show that the source of this strain may be either deep anomalous creep or a new form of shallow, distributed yielding in the top few kilometers of the crust. On the San Andreas fault, we show that this type of shallow yielding does occur, and its presence or absence is controlled by variations in the local normal stress that result from subtle bends in the fault. Finally, we investigate shallow creep on the Imperial fault, and show that thanks to observations from all parts of the earthquake cycle it is now possible to obtain a strong constraint on the shallow frictional rheology and depth of the material responsible for creep. The results also suggest activity on a hidden fault to the West, whose existence has been previously suggested but never confirmed.</p>
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5

Ouellette, Karli J. "Hydrologic applications of GPS site-position observations in the Western U.S." Thesis, University of California, Irvine, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3605189.

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<p> Permanent Global Positioning System (GPS) networks have been established around the globe for a variety of uses, most notably to monitor the activity of fault lines and tectonic plate motion. A model for utilizing GPS as a tool for hydrologic monitoring is also developed. </p><p> First, observations of the recent movement of the land surface throughout California by the Scripps Orbit and Permanent Array Center (SOPAC) GPS network are explored. Significant seasonal cycles and long term trends are related to historical observations of land subsidence. The pattern of deformation throughout the state appears to be caused by the occurrence of poroelastic deformation of the aquifer in the Central Valley, and elastic crustal loading by surface water and the winter snowpack in the Sierra Nevada Mountains. The result is a sort of teeter-totter motion between the Valley and the mountains where the Valley sinks in the dry season while the mountains lift, and the mountains sink in the wet season while the Valley lifts. </p><p> Next, the elastic crustal deformation caused by the winter snowpack is explored more thoroughly at 6 high elevations throughout the Western United States. Expected annual deformation as a result of thermoelastic and snow water equivalent are calculated using SNOTEL observations and an elastic half-space model. The results demonstrate the dominance of snow loading on the seasonal vertical land surface deformation at all 6 GPS stations. The model is then reversed and applied to the GPS vertical site-position observations in order to predict snow water equivalent. The results are compared to SNOTEL observations of snow water equivalent and soil moisture. The study concludes that GPS site-position observations are able to predict variations in snow water equivalent and soil moisture with good accuracy. </p><p> Then a model which incorporates both elastic crustal loading and poroelastic deformation was used to predict groundwater storage variations at 54 GPS stations throughout the Central Valley, CA. The results are compared to USGS water table observations from 43 wells. The predictions and observations show a similar magnitude and spatial pattern of groundwater depletion on both a seasonal and long term timescales. Depletion is focused on the southernmost part of the Valley where GPS reveals seasonal fluctuation of the water table around 2 m and 8 m/yr of water table decline during the study period. GPS also appears to respond to deformation from peat soils and changing reservoir storage in the northern parts of the Valley. </p><p> Finally, preliminary work exploring the potential for using GPS as a tool for monitoring snowmelt runoff and infiltration is explored at one station in Eastern Idaho. Taking the difference between the change in GPS water storage estimates with time and the change in SNOTEL observed snow water equivalent with time produces a time series of infiltration, or the amount of water added to storage in the geologic profile. Then subtracting the estimated infiltration and snow water equivalent from the total precipitation observed by SNOTEL produces a time series of runoff. The estimated runoff at the GPS site was compared to observations from a nearby stream gauge and the foundation for a more extensive comparison is laid out. </p><p> The overall impact of this work is to introduce the unique hydrologic information and monitoring capabilities which can be accessed through monitoring of the land surface position using GPS. As GPS networks grow and expand worldwide, the available data should be harnessed by the hydrologic community for the benefit of local water management as well as improvements to data assimilated models. The work presented here represents only a small fraction of the wealth of knowledge that could result from a budding field of GPS hydrologic remote sensing. (Abstract shortened by UMI.)</p>
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6

Madurapperuma, Buddhika Dilhan. "From Bray-Curtis ordination to Markov Chain Monte Carlo simulation| assessing anthropogenically-induced and/or climatically-induced changes in arboreal ecosystems." Thesis, North Dakota State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3589285.

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<p> Mapping forest resources is useful for identifying threat patterns and monitoring changes associated with landscapes. Remote Sensing and Geographic Information Science techniques are effective tools used to identify and forecast forest resource threats such as exotic plant invasion, vulnerability to climate change, and land-use/cover change. This research focused on mapping abundance and distribution of Russian-olive using soil and land-use/cover data, evaluating historic land-use/cover change using mappable water-related indices addressing the primary loss of riparian arboreal ecosystems, and detecting year-to-year land-cover changes on forest conversion processes. Digital image processing techniques were used to detect the changes of arboreal ecosystems using ArcGIS ArcInfo&reg; 9.3, ENVI&reg;, and ENVI&reg; EX platforms.</p><p> Research results showed that Russian-olive at the inundated habitats of the Missouri River is abundant compared to terrestrial habitats in the Bismarck-Mandan Wildland Urban Interface. This could be a consequence of habitat quality of the floodplain, such as its silt loam and silty clay soil type, which favors Russian-olive regeneration. Russian-olive has close assemblage with cottonwood (<i>Populus deltoides</i>) and buffaloberry (<i>Shepherdia argentea</i>) trees at the lower elevations. In addition, the Russian-olive-cottonwood association correlated with low nitrogen, low pH, and high Fe, while Russian-olive- buffaloberry association occurred in highly eroded areas.</p><p> The Devils Lake sub-watershed was selected to demonstrate how both land-use/cover modification and climatic variability have caused the vulnerability of arboreal ecosystems on the fringe to such changes. Land-cover change showed that the forest acreage declined from 9% to 1%, water extent increased from 13% to 25%, and cropland extent increased from 34% to 39% between 1992 and 2006. In addition, stochastic modeling was adapted to simulate how land-use/cover change influenced forest conversion to non-forested lands at the urban-wildland fringes in Cass County. The analysis yielded two distinct statistical groups of transition probabilities for forest to non-forest, with high transition probability of unchanged forest (0.54&le; Pff &le; 0.68) from 2006 to 2011. Generally, the land-uses, such as row crops, showed an increasing trend, while grains, hay, seeds, and other crops showed a declining trend. This information is vital to forest managers for implementing restoration and conservation practices in arboreal ecosystems.</p>
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7

Shcherbenko, Gina Nicole. "Post-Seismic Strain and Stress Evolution from Continuous GPS Observations." Thesis, State University of New York at Stony Brook, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1567846.

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<p> Strain evolution and stress evolution following the 4 April 2010 M7.2 El Mayor-Cucapah earthquake are modeled using an adaptation of the strain transient detection tool developed by <i>Holt and Shcherbenko</i> 2013. The evolution of stress is calculated from postseismic strains, which are modeled from continuous GPS horizontal displacements. Strain fields are modeled in 2 ways; the total strain field based on total observed cGPS displacements, and the residual strain field, which subtracts a reference field from the total model. The residual shows anomalous strains resulting from the postseismic relaxation of the 2010 event. Anomalous and total strains are modeled in 0.1 year epochs for 2.4 years following the event. Both total and anomalous strains are converted into stress changes over time, assuming elastic incompressible behavior. Following the El Mayor event, the GPS constrained strain evolution shows the following: (1) The Southern San Andreas experiences a reduced rate of right-lateral strike slip strain accumulation between 3 July 2010 and 7 August 2012 (Figure 16a-d). (2) The San Jacinto Fault has normal rate of right-lateral strike-slip strain accumulation during this time. (3) Before the Brawley swarm of 26 August 2012, the state of strain evolves to enable unclamping of a left-lateral fault zone in the Brawley Seismic Zone (Figure 16a-d). (4) Large shear strains accumulate on the Laguna Salada Fault (northernmost segment)/southern Elsinore FZ (Figure 16a-d). We converted the strain changes into Coulomb stress changes on existing faults (both right-lateral and left-lateral). Several regions show increased Coulomb stress changes throughout the postseismic process. Furthermore, the Coulomb stress changes on the faults in the region progressively increase toward failure up to the time of the Brawley swarm.</p>
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8

Atkinson, Brain M. "Characterization and delineation of caribou habitat on Unimak Island using remote sensing techniques." Thesis, University of Alaska Fairbanks, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1566796.

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<p> The assessment of herbivore habitat quality is traditionally based on quantifying the forages available to the animal across their home range through ground-based techniques. While these methods are highly accurate, they can be time-consuming and highly expensive, especially for herbivores that occupy vast spatial landscapes. The Unimak Island caribou herd has been decreasing in the last decade at rates that have prompted discussion of management intervention. Frequent inclement weather in this region of Alaska has provided for little opportunity to study the caribou forage habitat on Unimak Island. The overall objectives of this study were two-fold 1) to assess the feasibility of using high-resolution color and near-infrared aerial imagery to map the forage distribution of caribou habitat on Unimak Island and 2) to assess the use of a new high-resolution multispectral satellite imagery platform, RapidEye, and use of the "red-edge" spectral band on vegetation classification accuracy. Maximum likelihood classification algorithms were used to create land cover maps in aerial and satellite imagery. Accuracy assessments and transformed divergence values were produced to assess vegetative spectral information and classification accuracy. By using RapidEye and aerial digital imagery in a hierarchical supervised classification technique, we were able to produce a high resolution land cover map of Unimak Island. We obtained overall accuracy rates of 71.4 percent which are comparable to other land cover maps using RapidEye imagery. The "red-edge" spectral band included in the RapidEye imagery provides additional spectral information that allows for a more accurate overall classification, raising overall accuracy 5.2 percent.</p>
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9

Luke, Brandon Thomas. "Roman Pompeii, geography of death and escape| The deaths of Vesuvius." Thesis, Kent State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1555290.

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<p> Pompeii suffered a famous volcanic disaster in 79 AD. This led to a tremendous loss of life. This thesis examines that loss of life and the geography of death left behind by the eruption. Where did the citizens of Pompeii die, and how could they have avoided their fate? These are issues that are examined through geographic methodologies and the use of GIS. The results indicate a people that could have been spared with proper hazards management, and one that shows through mapping the large loss of life that accompanied one of history's most famous volcanic eruptions.</p>
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10

Brailo, Courtney M. "A Light Detecting and Ranging (LiDAR) and Global Positioning System (GPS) Study of the Truckee Meadows, NV. Quaternary Fault Mapping with ArcGIS, 3D Visualization and Computational Block Modeling of the Greater Reno area." Thesis, University of Nevada, Reno, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10126167.

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<p> The Truckee Meadows (Reno, NV) sits in a tectonically complex area of western Nevada, where Walker Lane-style transtension is dominant throughout the region. A new Light Detection and Ranging (LiDAR) study focuses on the Truckee Meadows region of western Nevada, including the Reno/Sparks metropolitan area in Washoe County. We use the airborne LiDAR imagery (1485 sq. km) to create high quality, bare-earth topographic maps that were previously unattainable in vegetated, populated or alpine terrain. This approach gives us an opportunity to improve fault maps that may be outdated or incomplete in the area. Here we provide LiDAR imagery of a large section of Washoe County and an updated fault map of the greater Truckee Meadows region. </p><p> We also use this new LiDAR survey of the Truckee Meadows and nearby basins to constrain geometry, length, distribution, and slip rates along faults imaged by this new dataset. Estimated slip rates are compared to those derived from a geodetic block model constrained by Global Positioning Station (GPS) data to test for consistency. GPS station data and geologic mapping show that both east-west oriented extension and northwest-oriented right-lateral strike slip accommodate transtension as a backdrop for tectonics studies of region, with some northeast-oriented left-lateral strike slip. This study aims to better understand how this transtension is partitioned along remapped faults and newly identified structures in this urban setting, as the framework for strain accommodation in this area remains poorly understood. </p><p> Faults with normal offset were measured along strike using bare-earth LiDAR returns to determine the amount of vertical separation across geomorphic surfaces, and then converted to extension assuming a fault dip of 60 (+/-10) degrees. Since the primary geomorphic surfaces in this region are the result of Sierra Nevadan glacial outwash episodes, we use previously published geologic maps to link each surface to an associated date. When integrated across several basin perpendicular transects within the Mt. Rose pediment, we calculate a total extension rate of 0.87 (+0.40/-0.48) mm/yr for the southern Truckee Meadows basin. Integrated slip rates from fault scarp offsets are within the bounds of 1.23 (+/-0.70) mm/yr suggested by geodetic modeling. Block modeling highlights that north-striking faults primarily accommodate east-west extension, and so northwest-striking faults and/or block rotations must accommodate the northwest-directed shear seen in GPS velocities. This trend is bolstered by the discovery of a new northwest-oriented fault on Peavine Mountain 6 km east of the Mogul (2008) seismicity trend. Our study provides further evidence that the Truckee Meadows sits at a critical transition from north-striking normal faults in the southern part of the basin to northwest-oriented strike-slip faults to the north, an observation that mimics regional tectonics and geomorphology of the adjacent Lake Tahoe/Truckee system to the west.</p>
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11

Pritsolas, Joshua. "Principal Component Analysis and Spatial Regression Techniques to Model and Map Corn and Soybean Yield Variability with Radiometrically Calibrated Multitemporal and Multispectral Digital Aerial Imagery." Thesis, Southern Illinois University at Edwardsville, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10807753.

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<p> Remotely sensed data has been discussed as a possible alternative to the standard precision agriculture systems of combine-mounted yield monitors because of the burden, cost, end of season use, and inherent errors that are associated with these systems. Due to the potential quantitative use of remote sensing in precision agriculture, the primary focus of this study was to test the relationship between multitemporal/multispectral digital aerial imagery with corn (<i>Zea mays</i> L.) and soybean (<i>Glycine max </i> L.) yield. Digital aerial imagery was gathered on nine different dates throughout the 2015 growing season from two fields (one corn and one soybean) located on a farm in Story County, Iowa. To begin assessing this relationship, the digital aerial imagery was radiometrically calibrated. The radiometric calibration process used calibration tarps with known reflectance values (3, 6, 12, 22, 44, and 56 percent). The calibrated imagery was then used to calculate and output 12 different vegetation indices (VIs) and three calibrated wavebands (red, green, and near-infrared). </p><p> Next, the calibrated VIs and wavebands from the 2015 growing season were used to examine their relationship with the corn and soybean yield data collected from a combine yield monitor system. This relationship between multitemporal/multispectral digital aerial imagery with corn and soybean yield was investigated with principal component analysis and spatial modeling techniques. The results from spatial modeling of corn revealed that VIs utilizing the green waveband performed strongly. VIs such as, chlorophyll index-green, chlorophyll vegetation index, and green normalized difference vegetation index accounted for 81.6, 83.0, and 82.4 percent of the yield variability, respectively. Strong modeling relationships were also found in soybean using just the near-infrared waveband or VIs that utilized the near-infrared waveband. The near-infrared waveband captured 89.1 percent of the yield variation, while VIs such as, difference vegetation index, triangular vegetation index, soil adjusted vegetation index, and optimized soil adjusted vegetation index accounted for 87.3, 87.3, 83.9, and 83.8 percent of soybean yield variability, respectively. The temporal assessment of the remotely sensed data also identified certain VIs and wavebands that captured pivotal growth stages for detecting potential yield limiting factors. These specific growth stages varied for different VIs and wavebands for both corn and soybean. Overall, the results from this study identified that mid-to-late vegetative growth stages (prior to tasseling) and late-season reproductive stages were important parameters that provided unique information in the modeling of corn yield variability, while the later reproductive stages (just prior to senescence) were essential to capturing soybean yield variability. </p><p> Lastly, this research produced corn and soybean yield maps from the digital aerial imagery. The digital aerial imagery yield maps were then compared with maps that used kriging interpolation of the combine yield monitor data gathered from the same corn and soybean fields. The results indicated that both corn and soybean yield maps produced with multitemporal/multispectral digital aerial imagery were comparable with a standard method of kriging interpolation from yield monitor data.</p><p>
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12

Grubbs, Melodie. "Beach Morphodynamic Change Detection using LiDAR during El Nino Periods in Southern California." Thesis, University of Southern California, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10257407.

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<p> Light Detection and Ranging (LiDAR) technology combined with high-resolution differential Global Positioning Systems (dGPS) provide the ability to measure coastal elevation with high precision. This study investigates the use of LiDAR data and GIS to conduct time-series analyses of coastal sediment volume shifts during the 2006-2007 El Ni&ntilde;o winter, Summer of 2007 and following 2007-2008 La Ni&ntilde;a winter in the Oceanside Littoral Cell (OLC). The OLC, located in Southern California, spans from Dana Point to La Jolla and includes over 84 km of coastline. The ability to quantify sediment volume changes contributes to the scientific understanding of the role El Ni&ntilde;o storms play in the OLC sand budget. This study provides a method to analyze LiDAR data to evaluate coastal geomorphologic changes over time. Additionally, identifying specific areas of coastal beach erosion associated with historical El Ni&ntilde;o events can aid beach managers, planners, and scientists in protecting the valuable coastline. LiDAR datasets were prepared and formatted which included ground classifying millions of elevation points. Formatted datasets were inputted into an Empirical Bayesian Kriging (EBK) model, creating high-resolution, 1-meter grid cell, Digital Elevation Models (DEMs). The EBK model also incorporated uncertainty into the workflow by producing prediction error surfaces. LiDAR-derived DEMs were used to calculate sediment volume changes through a technique called DEM differencing. Results were visualized through a series of maps and tables. Overall results show that there was a higher rate of beach sediment erosion during the 2006-2007 El Ni&ntilde;o winter than the 2007-2008 La Ni&ntilde;a winter. Sediment accretion was evident during the intermediary Summer of 2007. Future applications of this study include incorporating bathymetric datasets to understand near-shore sediment transport, evaluating sediment contribution through cliff erosion, and conducting decadal scale studies to evaluate long-term trends with sea level rise scenarios. </p>
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GAMA, Nicolas Alexandre. "Validação das estimativas de precipitação observadas pelo Tropical Rainfall Measuring Mission para o Brasil." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18868.

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Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-05-23T15:38:53Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Gama, N.A. (2016) - Validação das Estimativas de Precipitação Observadas pelo Tropical Rainfall Measuring Mission para o ~1.pdf: 9989783 bytes, checksum: cbd93ee88254c673fdb01934acc83002 (MD5)<br>Made available in DSpace on 2017-05-23T15:38:53Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Gama, N.A. (2016) - Validação das Estimativas de Precipitação Observadas pelo Tropical Rainfall Measuring Mission para o ~1.pdf: 9989783 bytes, checksum: cbd93ee88254c673fdb01934acc83002 (MD5) Previous issue date: 2016-03-11<br>CAPES<br>A precipitação é considerada um elemento fundamental e de grande importância no ciclo hidrológico, pois é através dela que é feita a recarga hídrica nas bacias hidrográficas e nas reservas subterrâneas.O monitoramento meteorológico é de grande importância para as nações, este monitoramento pode ser feito através de diversos métodos e instrumentos, sejam eles terrestres ou orbitais. No Brasil problemas relacionados à seca tornam-se preocupantes e estão presentes na sociedade moderna. O estudo e entendimento de comportamentos de padrões espaciais de informações sobre precipitações é uma ferramenta importante para a tomada de decisão. Observações obtidas por sensores a bordo de satélites artificiais na órbita da Terra auxiliam na medição do volume de chuva em uma dada região. Para esta dissertação foram utilizados como materiais um conjunto de dados gratuitos de precipitação do TRMM (TROPICAL RAINFALL MEASURING MISSION) através de um dos seus produtos disponíveis chamado de Rainfall Product (3B43). Atualmente estes recursos vêm sendo utilizado em diversas pesquisas onde entre suas vantagens encontram-se: a periodicidade de amostragem (resolução temporal) e abrangência superior às estações meteorológicas. Porém, as observações dos sensores orbitais apresentam algumas desvantagens como, por exemplo, a resolução espacial da informação da precipitação, sendo recomendado estabelecer critérios para as análises e validação das estimativas. Sendo assim, além de dados orbitais, informações sobre séries históricas de precipitação obtidas por estações meteorológicas que são operados por diversos órgãos públicos foram utilizadas. Desta forma, foram delineados objetivos para essa pesquisa sendo eles: (i) avaliar os dados do TRMM, a fim de valida-los como um instrumento de monitoramento de precipitação para o Brasil; (ii) comparar as informações históricas do TRMM as respectivas estações de campo em amostras no território brasileiro e assim determinar a correlação entre estes produtos; (iii) Avaliar os dados TRMM de precipitação com base no período de 2000 até 2014 aplicando um teste de normalidade a fim de verificar regiões onde existe maior igualdade estatística entre os produtos. Para a avaliação e validação dos dados do produto TRMM 3B43 em relação às séries históricas das estações meteorológicas, foram feitas análises estatísticas como a correlação entre os dados e o teste de Kolmogorov-Smirnov entre as duas Grades de informações. Espera-se através desta pesquisa contribuir com o uso e divulgação de informações temporais do TRMM para o monitoramento de precipitação no território brasileiro. Através da análise estatística entre os dois conjuntos de dados, percebeu-se que há sim a possibilidade de utilização dos dados do satélite TRMM para verificar o comportamento das curvas de precipitação, contribuindo ainda mais em regiões onde há escassez de dados in situ como o caso da região Amazônica.<br>Meteorological monitoring is considered very important to the nations, andthis can be done through various methods and instruments, among them are the terrestrial and orbital. In Brazil droughtrelated problems become worrisome and are present in modern society.The study and understanding of behaviors of spatial patterns about precipitations is an important tool for decision making. Observations obtained by remote sensingusing artificial satellites can give support for mesuring rainfall in a given region. The materials used in this work was a set of free rainfall data from TRMM (Tropical Rainfall Measuring Mission) considering Rainfall Product (3B43). Nowawadaysthese resources have been used in several researches presenting some advantges and between these are: sampling frequency (temporal resolution) and higher coverage compared to the insitu stations. However, there are some disadvantages, for e.g., the rainfall spatial resolution and the requirement to establish some criteria for analysis and data validatiing. Therefore, in addition to orbital data, information on historical precipitation series obtained by insitu stations that are operated by public organizations has been used. Thus, goals have been set for this research which are: (i) evaluate the TRMM data in order to validate it as a rainfall monitoring instrument for Brazil; (ii) obtain satellite TRMM historic information and in situ rainfall stations over Brazil and determine the correlation between these products; (iii) evaluate TRMM records of precipitation based during 2000 until 2014 period, and applying on them a normality test to verify regions where there is more statistical equality between the products. For the evaluation and validation of TRMM 3B43 product data in relation to historical series from in situ stations, statistical analyzes were made as the correlation between the observations using the Kolmogorov-Smirnov test between the two Grids information. It is expected through this research to contribute to the use and disclosure of TRMM temporal information for rainfall monitoring in Brazil. Through statistical analysis of the two sets of data, it was realized that there is the possibility of using the TRMM satellite data to verify the behavior of precipitation curves, further contributing in areas where there are few data in situ as the case of the Amazon region.
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Anderson, Eric Ross. "Analysis of rainfall-triggered landslide hazards through the dynamic integration of remotely sensed, modeled and in situ environmental factors in El Salvador." Thesis, The University of Alabama in Huntsville, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1543417.

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<p> Landslides pose a persistent threat to El Salvador's population, economy and environment. Government officials share responsibility in managing this hazard by alerting populations when and where landslides may occur as well as developing and enforcing proper land use and zoning practices. This thesis addresses gaps in current knowledge between identifying precisely when and where slope failures may initiate and outlining the extent of the potential debris inundation areas. Improvements on hazard maps are achieved by considering a series of environmental variables to determine causal factors through spatial and temporal analysis techniques in Geographic Information Systems and remote sensing. The output is a more dynamic tool that links high resolution geomorphic and hydrological factors to daily precipitation. Directly incorporable into existing decision support systems, this allows for better disaster management and is transferable to other developing countries.</p>
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Rafiq, Talha. "A temporal and ecological analysis of the Huntington Beach Wetlands through an unmanned aerial system remote sensing perspective." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1597786.

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<p>Wetland monitoring and preservation efforts have the potential to be enhanced with advanced remote sensing acquisition and digital image analysis approaches. Progress in the development and utilization of Unmanned Aerial Systems (UAS) and Unmanned Aerial Vehicles (UAV) as remote sensing platforms has offered significant spatial and temporal advantages over traditional aerial and orbital remote sensing platforms. Photogrammetric approaches to generate high spatial resolution orthophotos of UAV acquired imagery along with the UAV?s low-cost and temporally flexible characteristics are explored. A comparative analysis of different spectral based land cover maps derived from imagery captured using UAV, satellite, and airplane platforms provide an assessment of the Huntington Beach Wetlands. This research presents a UAS remote sensing methodology encompassing data collection, image processing, and analysis in constructing spectral based land cover maps to augment the efforts of the Huntington Beach Wetlands Conservancy by assessing ecological and temporal changes at the Huntington Beach Wetlands.
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Hong, Chang-Ki. "Efficient differential code bias and ionosphere modeling and their impact on the network-based GPS positioning." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1190083730.

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Niu, Xutong. "Highway extraction from high resolution aerial photography using a geometric active contour model." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1101833084.

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Zhu, Lizhi. "Gradient modeling with gravity and DEM." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1180110427.

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19

Anibas, Kyle Lawrence. "Land cover, land use and habitat change in Volyn, Ukraine : 1986-2011." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17682.

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Master of Science<br>Department of Geography<br>Douglas G. Goodin<br>Volyn Oblast in Western Ukraine has experienced substantial land use/land cover change over the last 25 years as a result of a change in political systems. Remote sensing provides a framework to quantify this change without extensive field work or historical land cover records. In this study, land change is quantified utilizing a post-classification change detection technique comparing Landsat imagery from 1986-2011(Post-Soviet era began 1991). A variety of remote sensing classification methods are explored to take advantage of spectral and spatial variation within this complex study area, and a hybrid scheme is ultimately utilized. Land cover from the CORINE classification scheme is then converted to the EUNIS habitat classification scheme to analyze how land cover change has affected habitat fragmentation. I found large scale agricultural abandonment, increases in forested areas, shifts towards smaller scale farming practices, shifts towards mixed forest structures, and increases in fragmentation of both forest and agricultural habitat types. These changes could have several positive and negative on biodiversity, ecosystems, and human well-being.
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Tu, Denise Shao-Wai. "Assessment of Methods for Monitoring Responses to River Restoration: Riverbed and Channel Form Changes." Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11505.

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xi, 54 p. : ill. (some col.)<br>On the Middle Fork John Day River (MFJD), a low gradient, meandering river in eastern Oregon, restoration includes engineered log structures intended to increase in-stream complexity and habitat diversity. Effects of log structures on riverbed topography can be captured through repeat topographic surveys, digital elevation model (DEM) of differencing (DoD), and aerial imagery. This study evaluates the (1) potential for remote sensing analysis, (2) effect of survey point density on DEMs, and (3) application of DoDs, in monitoring riverbed changes in the MFJD. An average point spacing and density finer than 0.50m and 1.25pts/m<super>2</super> captures riverbed complexities. Although elevation changes were expected to be minimal, DoDs revealed -0.9 to 0.5m elevation changes associated with log structure designs. Incorporating numerical thresholds into future monitoring survey methods will improve the modeling of MFJD riverbed surfaces. Monitoring riverbed changes through DoDs can inform improvements to future restoration design and the effectiveness of log structures.<br>Committee in charge: Patricia McDowell, Chairperson; Andrew Marcus, Member
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Burchfield, David Richard. "Mapping eastern redcedar (Juniperus Virginiana L.) and quantifying its biomass in Riley County, Kansas." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18404.

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Master of Arts<br>Department of Geography<br>Kevin P. Price<br>Due primarily to changes in land management practices, eastern redcedar (Juniperus virginiana L.), a native Kansas conifer, is rapidly invading onto valuable rangelands. The suppression of fire and increase of intensive grazing, combined with the rapid growth rate, high reproductive output, and dispersal ability of the species have allowed it to dramatically expand beyond its original range. There is a growing interest in harvesting this species for use as a biofuel. For economic planning purposes, density and biomass quantities for the trees are needed. Three methods are explored for mapping eastern redcedar and quantifying its biomass in Riley County, Kansas. First, a land cover classification of redcedar cover is performed using a method that utilizes a support vector machine classifier applied to a multi-temporal stack of Landsat TM satellite images. Second, a Small Unmanned Aircraft System (sUAS) is used to measure individual redcedar trees in an area where they are encroaching into a pasture. Finally, a hybrid approach is used to estimate redcedar biomass using high resolution multispectral and light detection and ranging (LiDAR) imagery. These methods showed promise in the forestry, range management, and bioenergy industries for better understanding of an invasive species that shows great potential for use as a biofuel resource.
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Blackmore, Debra Sue. "Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge." Thesis, Portland State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10191067.

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<p> 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.</p>
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Donner, Ralf. "Die visuelle Interpretation von Fernerkundungsdaten." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek &quot;Georgius Agricola&quot, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-095192.

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Die Fähigkeit, in Luft- und Satellitenbildern Objekte wiederzuerkennen, kann folgendermaßen erklärt werden: Aus der Kenntnis einer Landschaft und ihrer Abbildung im Bild werden Interpretationsregeln entwickelt, die bestimmten Kombinationen von Bildmerkmalen wie Farbe, Form, Größe, Textur oder Kontext festgelegte Bedeutungen zuordnen. Kommt es nicht auf das Wiedererkennen mit festen Wahrnehmungsmustern an, stellt sich die bislang offene Frage nach einer wissenschaftlichen Kriterien genügenden Methode, wie der gedankliche Zusammenhang zwischen den Sinneswahrnehmungen erfasst werden kann. Die Erfahrung von Umkehrbildern und optischen Täuschungen führt zur Frage nach dem festen Element bei der visuellen Interpretation von Fernerkundungsdaten. Galileis Antwort, Messwerte als Ausgangspunkt naturwissenschaftlicher Erkenntnis zu nehmen, löst die Mehrdeutigkeiten und Unsicherheiten gedanklicher Interpretationen nicht auf, denn zu jeder Zahl gehört bereits eine gedankliche Bestimmung darüber, was sie bedeutet: Äpfel, Birnen, Höhendifferenzen … Daher muss für die begriffliche Interpretation der Wahrnehmungen ein anderer Ausgangspunkt bestimmt werden: Weder kann der Mensch beobachten oder wahrnehmen, ohne seine Erlebnisse gedanklich zu fassen und zu ordnen, noch ist die Sinnesempfindung ein subjektives, vom Gegenstand abgespaltenes, nur persönliches Erlebnis. Wahrnehmung realisiert sich als Einheit von Wahrnehmendem und Wahrgenommenen. Demzufolge gibt es keine binäre Unterscheidung von objektiver Tatsache und subjektiver Interpretation. Wahrnehmung findet zwischen den Polen reiner Empfindung eines gegebenen und sinnlichkeitsfreien Denkens statt. Die reinen Erlebnisqualitäten der Sinnesempfindungen (warm, kalt, hell, rau) stellen sich als die am wenigsten von der subjektiven gedanklichen Interpretation abhängigen Elemente des Erkenntnisprozesses dar. Diesem Verhältnis von Beobachtung und gedanklicher Deutung entspricht ein phänomenologischer Untersuchungsansatz. Mit ihm bekommen Erfahrungen als absolute Elemente der Wahrnehmung primäre Bedeutung, gedankliche Interpretationen werden zu Abhängigen. Daher werden in der Untersuchung Ergebnisse phänomenologischer Arbeiten bevorzugt. Auch die eigene Bearbeitung des Themas geht von einer konsequent empirischen Position aus. Um einen Sachverhalt zu verstehen, genügt es nicht, bei den Sinnesempfindungen stehen zu bleiben, denn zu ihrem Verständnis fehlt der gedankliche Zusammenhang, die Erlebnisse müssen begrifflich interpretiert werden. Dabei ist die Doppelrolle der Begriffe von entscheidender Bedeutung: In der Analyse grenzen sie innerhalb des Erfahrungsfeldes Teilaspekte gegeneinander ab, welche in der Synthese durch dieselben Begriffe gedanklich verbunden werden. Diese Funktion der Begriffe wird ausgenutzt, um Wiedererkennen und Bildung von Verständnis zu differenzieren: Die Interpretation der Erfahrung nach a priori vorgegebenen Mustern zielt auf das Wiedererkennen. Im Gegensatz dazu emergiert Verständnis im Prozess der Begriffsbildung aus den Beobachtungen: Man sucht erst nach einer Gliederung, welche eine gedankliche Synthese plausibel erscheinen lässt. Das Konzept der Selbstorganisation hat in der Ökologie mechanistische Vorstellungen weitgehend abgelöst und im letzten Jahrzehnt auch in die Technik Eingang gefunden. Mit den Worten dieses Konzeptes kann die Begriffsbildung als Erkenntnisprozess beschrieben werden, in welchem sich gedankliche und nichtgedankliche Wahrnehmungen selbst organisieren. Sinnesempfindungen haben auch in anderen Zugangsweisen zur Natur eine dominierende Stellung. Daher können Goetheanismus, wissenschaftliche Ästhetik und Kunst zu einer voraussetzungslosen Naturerkundung beitragen. Die nahe Verwandtschaft von Phänomenologie, Ästhetik und Kunst lässt künstlerisches Schaffen als Vervollkommnung des in der Natur Veranlagten erscheinen. Weitere Querbeziehungen ergeben sich aus der Interpretation topografischer oder thematischer Karten oder sonstiger visualisierter raumbezogener Daten. Parallelen und Unterschiede werden herausgearbeitet. Moderne Naturwissenschaft ist quantitativ. Daher ist zu klären, was mathematische Modellierung zur Verständnisbildung beiträgt. In diesem Teil der Arbeit ist es der folgende Gedanke, welcher über die hinlänglich bekannte Nützlichkeit mathematischer Modellierungen, Vorausberechnungen und Simulationen hinausgeht: Die Mathematik überzeugt durch ihre logische Strenge in der Ableitung und Beweisführung: Aus Obersatz und Untersatz folgt die Konklusion. Eine Beobachtungsmethode, bei welcher eine Beobachtung an die nächste gereiht wird, so dass sich das Eine aus dem Anderen ergibt, wobei kein Sprung die Folge unterbricht, käme der Notwendigkeit eines mathematischen Beweises gleich. Diese strenge Folge des Einen aus dem Anderen tritt in der wissenschaftlichen Argumentation an die Stelle der spontanen Intuition mit Verifikation, Falsifikation und bestätigendem Beispiel. Auf diese Weise kann durch die Anwendung der mathematischen Methode eine realitätsnahe Begriffsbildung erreicht werden. Die bis hierher dargelegten Aspekte der Wahrnehmung, der Ästhetik, der Kunst und der Mathematik werden in der Methode einer voraussetzungslosen Begriffsentwicklung zusammengefasst. Damit ist das Hauptziel der Untersuchung, die Entwicklung einer auf das Verständnis gerichteten erfahrungsbasierten Beobachtungsmethode, erreicht. Die Abhandlung wird mit der Anwendung der entwickelten Methode auf einen Grundbegriff der Geoinformatik in folgender Weise fortgesetzt: Für die Geoinformatik ist der Raumbegriff von grundlegender Bedeutung. Daher bietet es sich an, diesen Begriff unter Anwendung der entwickelten Methode zu untersuchen. Unter phänomenologischen Gesichtspunkten stehen Raum und Zeit in einem engen Zusammenhang. Beide werden in der Bewegung erfahren. Interpretiert man Bewegung mit den Begriffen des Nebeneinander und des Nacheinander, entsteht Wissen von Raum und Zeit. Mit anderen Worten: Die am Leib erfahrene Bewegung wird durch Interpretation mit dem Raumbegriff zur Vorstellung durchlaufener Orte. Je nachdem, welche Sinneserfahrungen, allgemeiner: Beobachtungen, zugrunde gelegt werden, hat der Raum unterschiedliche geometrische Eigenschaften. Die Erfahrungen des Tastsinnes begründen euklidische Beobachtungen. Die Begriffe Raum und Zeit haben für die Verständnisbildung eine fundamentale Bedeutung. Mit ihrer Hilfe können die Erlebnisse als zugleich und nebeneinander oder als nacheinander geordnet werden. Sie ermöglichen Erkenntnis durch Analyse und Synthese. Wesentliches Motiv der Untersuchung ist die Frage nach der Bildung von Verständnis im Rahmen der visuellen Interpretation. Das Erkennen von Objekten stellt sich als synästhetische Synthese der Sinnesempfindungen und gedanklicher Inhalte dar. Unterschiedliche Gewichtungen der Gedankeninhalte lassen zwei Vorgehensweisen unterscheiden: 1, Für das Erkennen von Neuem ist es von grundlegender Bedeutung, dass die gedanklichen Inhalte den nichtgedanklichen Sinnesempfindungen untergeordnet sind, das heißt von diesen modifiziert werden können. Vorgewussten Begriffen kommt die Rolle von Hypothesen zu. 2, Beim Wiedererkennen haben gedankliche Inhalte eine dominierende Rolle – anhand von Interpretationsmerkmalen sollen Bildinhalten Bedeutungen zugewiesen werden. Das Bild wird hierzu nach Bildflächen mit solchen Kombinationen von Farben, Formen, Mustern, Texturen und räumlichen Anordnungen durchsucht, die dem zu suchenden Begriff entsprechen können. Oder das Bild wird, bei Verwendung einer Art Beispielschlüssel, nach Übereinstimmungen mit kompletten Bildmustern durchsucht. Auch das ist eine Form des Wiedererkennens. Um ein Phänomen zu verstehen, kommt es darauf an, in der Regelmäßigkeit der äußeren Form den Zusammenhang zu entdecken, der den verschiedenartigen Ausgestaltungen als regelndes Element zugrunde liegt. Dazu muss über eine Klassifizierung von Interpretationsmerkmalen hinausgegangen werden. Die gedankliche Auseinandersetzung mit den visualisierten Repräsentanzen der Phänomene unterstützt die Bildung eines solchen ideellen Zusammenhangs, welcher das in aller Mannigfaltigkeit der natürlichen Erscheinungen Gleichbleibende, Ruhende darstellt, aus welchem die Einzelphänomene hervorgegangen sein könnten. Die Funktionen beschreiben die Wechselwirkungen zwischen den räumlichen Elementen, welche sich in Austauschprozessen von Energie, Material und Stoffen ausdrücken. Überall dort, wo räumliche Anordnung ein Ausdruck funktionaler Beziehungen ist, unterstützt die visuelle Wahrnehmung der räumlichen Beziehungen die Einsicht in die sachlichen. In den Schlussfolgerungen wird die Visualisierung von Geodaten als Mittel zur Sichtbarmachung des Zusammenhanges zwischen den Erscheinungen charakterisiert. Die Bezugnahme zur Fernerkundung führt zu der Feststellung, dass die Anwendung der vorgeschlagenen Forschungsstrategie im Bereich der Geofernerkundung nur eingeschränkt möglich ist.
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Cabezas, Rabadán Carlos. "Beach Morphology and its Dynamism from Remote Sensing for Coastal Management Support." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/165076.

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[ES] Las playas son espacios costeros que desarrollan numerosas funciones ambientales. Éstas proporcionan importantes beneficios a la sociedad y a las comunidades costeras, entre las que destacan la función ecológica, el suministro de protección para los territorios costeros y el hecho de que constituyen un recurso básico de la industria turística. De forma ligada al cambio climático, así como a acciones humanas que alteran el dinamismo natural de la costa, las playas están experimentando procesos erosivos cada vez más dañinos que afectan a su integridad física y al mantenimiento de sus funciones. La gestión de las playas en muchas ocasiones no se encuentra adaptada a las particularidades de los diferentes segmentos costeros. La toma de decisiones no se sustenta en información suficiente sobre las características, el dinamismo y el estado actual de las playas, dando lugar a soluciones cortoplacistas o ineficaces. Las características geomorfológicas son esenciales en el desarrollo de sus funciones al condicionar sus dimensiones físicas y su comportamiento frente a la acción del mar. Por ello, su caracterización de forma detallada y actualizada es necesaria para llevar a cabo acciones eficientes, permitiendo virar hacia una gestión costera más ecosistémica y sostenible. Las técnicas de teledetección presentan una gran capacidad para la adquisición de datos de la superficie terrestre. En concreto, los satélites Sentinel-2 y Landsat (5, 7 y 8) permiten disponer de forma gratuita imágenes de resolución media con cobertura mundial y alta frecuencia de revisitado. Los algoritmos de extracción de la línea de costa desarrollados recientemente por el Grupo de Cartografia GeoAmbiental y Teledetección (CGAT - UPV) permiten definir sobre estas imágenes la posición de la línea de costa, constituyendo datos potencialmente útiles para describir la morfología de las playas y su dinamismo. Universalizar su aplicación requiere su testeo y validación en diferentes tipos de costa. Para ello, el proceso de extracción ha sido adaptado para su explotación en entornos mareales, y las líneas de costa resultantes han sido evaluadas ante diferentes condiciones oceanográficas ofreciendo una precisión cercana a los 5 m RECM (raíz del error cuadrático medio). Teniendo en cuenta las necesidades de información para la gestión existentes, a partir de estas líneas de costa se propone derivar indicadores que permitan caracterizar la geomorfología de las playas y monitorizar sus cambios. Para ello, las metodologías propuestas aseguran una gestión eficiente de grandes volúmenes de líneas de costa, siendo así capaces de caracterizar las playas cubriendo grandes territorios y periodos de tiempo. Así se derivan el ancho de playa y el tamaño de los granos de sedimento como indicadores objetivos y fácilmente comprensibles de la geomorfología de la playa. La modelización espacio-temporal del estado y los cambios de la línea de costa y de la anchura posibilita monitorizar la respuesta de las playas a temporales y a actuaciones antrópicas, permitiendo analizar los cambios ocurridos cada pocos días hasta cubrir décadas. Su cobertura espacial junto a la integración con otras bases de datos cartográficas permite caracterizar la influencia de la geomorfología de la playa en el desempeño de sus funciones, permitiendo un análisis holístico de la costa a escala regional. Las metodologías desarrolladas en esta tesis y los indicadores derivados desde la teledetección brindan apoyo para dotar de criterios y priorizar las acciones de los gestores. Se contribuye así a llenar el espacio existente entre la disponibilidad de técnicas para obtener información remota y su aplicación en los procesos de toma de decisiones sobre la costa.<br>[CAT] Les platges són espais costaners que desenvolupen nombroses funcions ambientals. Aquestes proporcionen importants beneficis a la societat i comunitats costaneres, entre les quals destaquen la funció ecològica, el subministrament de protecció per als territoris costaners i el fet que constitueixen un recurs bàsic de la indústria turística. De forma lligada al canvi climàtic, així com a accions humanes que alteren el dinamisme natural de la costa, les platges estan experimentant processos erosius cada vegada més nocius que afecten la seua integritat física i al manteniment de les seues funcions. La gestió de les platges en moltes ocasions no es troba adaptada a les particularitats dels diferents segments costaners. La presa de decisions no es sustenta en informació suficient sobre les característiques, el dinamisme i l'estat actual de les platges, donant lloc a solucions curtterministes o ineficaces. Les característiques geomorfològiques són essencials en el desenvolupament de les seues funcions en condicionar les seues dimensions físiques i el seu comportament enfront de l'acció de la mar. Per això, la seua caracterització de manera detallada i actualitzada és necessària per a dur a terme accions eficients, permetent virar cap a una gestió costanera més ecosistèmica i sostenible. Les tècniques de teledetecció presenten una gran capacitat per a l'adquisició de dades de la superfície terrestre. En concret, els satèl·lits Sentinel-2 i Landsat (5, 7 i 8) permeten disposar de manera gratuïta d'imatges de resolució mitjana amb cobertura mundial i alta freqüència de captura d'informació a un mateix punt. Els algorismes d'extracció de la línia de costa desenvolupats recentment pel Grup de Cartografia Geo-Ambiental i Teledetecció (CGAT - UPV) permeten definir sobre aquestes imatges la posició de la línia de costa, constituint dades potencialment útils per descriure la morfologia de les platges i el seu dinamisme. Universalitzar la seua aplicació requereix el seu testatge i validació en diferents tipus de costa. Per a això, el procés d'extracció ha sigut adaptat per a la seua explotació en entorns mareals, i les línies de costa resultants han sigut avaluades davant diferents condicions oceanogràfiques oferint una precisió pròxima als 5 m RMSE (arrel de l'error quadràtic mitjà). Tenint en compte les necessitats d'informació per a la gestió existents, a partir d'aquestes línies de costa es proposa derivar indicadors que permeten caracteritzar la geomorfologia de les platges i monitorar els seus canvis. Per a això, les metodologies proposades asseguren una gestió eficient de grans volums de línies de costa, sent així capaces de caracteritzar les platges cobrint grans territoris i períodes de temps. Així es deriven l'ample de platja i la grandària dels grans de sediment com a indicadors objectius i fàcilment comprensibles de la geomorfologia de la platja. La modelització espai-temporal de l'estat i els canvis de la línia de costa i de l'amplària possibilita monitorar la resposta de les platges a temporals i a actuacions antròpiques, permetent analitzar els canvis ocorreguts cada pocs dies fins a cobrir dècades. La seua cobertura espacial al costat de la integració amb altres bases de dades cartogràfiques permet caracteritzar la influència de la geomorfologia de la platja en l'acompliment de les seues funcions, permetent una anàlisi holística de la costa a escala regional. Les metodologies desenvolupades en aquesta tesi i els indicadors derivats des de la teledetecció brinden suport per a dotar de criteris i prioritzar les accions dels gestors. Es contribueix així a omplir l'espai existent entre la disponibilitat de tècniques per a obtenir informació remota i la seua aplicació en els processos de presa de decisions sobre la costa.<br>[EN] Beaches are coastal spaces that perform numerous environmental functions. They provide important benefits to society and coastal communities, including the ecological function, the provision of protection for coastal territories, and constitute a basic resource for the tourism industry. Due to climate change and human actions that alter the natural dynamism of the coast, beaches are experiencing increasingly harmful erosive processes that affect their physical integrity and the maintenance of their ecological functions. Beach management is often not adapted to the particularities of the different coastal segments. Decision-making is not based on sufficient information about characteristics, dynamism, and current state of beaches, resulting in short or ineffective solutions. Geomorphological characteristics are essential in the development of beach functions as they condition their physical dimensions and their behavior in response to the action of the sea. Therefore, their detailed and updated characterization is necessary to carry out efficient actions, allowing a more ecosystemic and sustainable coastal management. Remote sensing techniques have a great capacity for acquiring data from the land surface. In particular, Sentinel-2 and Landsat (5, 7, and 8) satellites freely provide medium resolution images with global coverage and high-revisit frequency. The algorithms for extracting the water/land interface recently developed by the Geo-Environmental Cartography and Remote Sensing Group (CGAT - UPV) allow defining the position of the shoreline on these images, constituting potentially useful data to describe beach morphology and dynamics. Universalizing their application requires testing and validation at different coastal types. For this purpose, the extraction process has been adapted for exploitation in tidal environments, and the resulting shorelines have been assessed under different oceanographic conditions offering an accuracy close to 5 m RMSE (Root-Mean-Square Error). From these shorelines, and taking into account the existing information needs for management, it is proposed to derive indicators to characterize the geomorphology of the beaches and to monitor their changes. To this end, the proposed methodologies ensure the efficient management of large volumes of shorelines, being able to characterize the beaches along broad coastal segments and periods. Thus, beach width and sediment grain size are derived as objective and easily understandable indicators of the beach geomorphology. Spatial-temporal modeling of the state and changes of shoreline position and beach width makes it possible to monitor the response to storms and anthropogenic actions, allowing to analyze changes that occur every few days or over decades. The large spatial coverage together with the integration with other cartographic databases allows characterizing the influence of beach geomorphology in the performance of its functions, offering a holistic view of the coast from a regional scale. The methodologies developed in this thesis and the indicators derived from remote sensing provide support and criteria for prioritizing the actions of managers. This contributes to fill the gap between the availability of techniques to obtain remote information and its application in the coastal decision-making process.<br>This research integrates findings and results obtained within the framework of the contract FPU15/04501 granted to the author by the Spanish Ministry of Education, Culture, and Sports, which has allowed this doctoral thesis to become a reality. The research has been supported by the funds of the project RESETOCOAST, by the Ministry of Economy, Industry, and Competitiveness (chapters 2 to 5), and the project MONOBESAT PID2019-111435RB-I00 by the Ministry of Science, Innovation, and Universities (chapter 6). About my stay in Portugal, it was possible with the funds of the Erasmus+ program. The contribution of Ó. Ferreira was funded by EW-COAST (PTDC/CTA-OHR/28657/2017) and by FCT and Univ. Algarve through the grant UID/MAR/00350/2013, while S. Costas’ was funded by IF/01047/2014. The following institutions have provided free access to essential data for the development of the publications that constitute this thesis: ESA and USGS for the satellite imagery; Puertos del Estado, and the Portuguese Hydrographic Institute in collaboration with CIMA for supplying oceanographic data; Ministry MITECO and DGSCM for data regarding beach sedimentology and nourishments.<br>Cabezas Rabadán, C. (2021). Beach Morphology and its Dynamism from Remote Sensing for Coastal Management Support [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165076<br>TESIS
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Facciolo, Furlan Gabriele. "Irregularly sampled image resortation and interpolation." Doctoral thesis, Universitat Pompeu Fabra, 2011. http://hdl.handle.net/10803/22714.

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The generation of urban digital elevation models from satellite images using stereo reconstruction techniques poses several challenges due to its precision requirements. In this thesis we study three problems related to the reconstruction of urban models using stereo images in a low baseline disposition. They were motivated by the MISS project, launched by the CNES (Centre National d'Etudes Spatiales), in order to develop a low baseline acquisition model. The first problem is the restoration of irregularly sampled images and image fusion using a band limited interpolation model. A novel restoration algorithm is proposed, which incorporates the image formation model as a set of local constraints, and uses of a family of regularizers that allow to control the spectral behavior of the solution. Secondly, the problem of interpolating sparsely sampled images is addressed using a self-similarity prior. The related problem of image inpainting is also considered, and a novel framework for exemplar-based image inpainting is proposed. This framework is then extended to consider the interpolation of sparsely sampled images. The third problem is the regularization and interpolation of digital elevation models imposing geometric restrictions. The geometric restrictions come from a reference image. For this problem three different regularization models are studied: an anisotropic minimal surface regularizer, the anisotropic total variation and a new piecewise affine interpolation algorithm.<br>La generación de modelos urbanos de elevación a partir de imágenes de satélite mediante técnicas de reconstrucción estereoscópica presenta varios retos debido a sus requisitos de precisión. En esta tesis se estudian tres problemas vinculados a la generación de estos modelos partiendo de pares estereoscópicos adquiridos por satélites en una configuración con baseline pequeño. Estos problemas fueron motivados por el proyecto MISS, lanzado por el CNES (Centre National d'Etudes Spatiales) con el objetivo de desarrollar las técnicas de reconstrucción para imágenes adquiridas con baseline pequeños. El primer problema es la restauración de imágenes muestreadas irregularmente y la fusión de imágenes usando un modelo de interpolación de banda limitada. Se propone un nuevo método de restauración, el cual usa una familia de regularizadores que permite controlar el decaimiento espectral de la solución e incorpora el modelo de formación de imagen como un conjunto de restricciones locales. El segundo problema es la interpolación de imágenes muestreadas en forma dispersa usando un prior de auto similitud, se considera también el problema relacionado de inpainting de imágenes. Se propone un nuevo framework para inpainting basado en ejemplares, el cual luego es extendido a la interpolación de imágenes muestreadas en forma dispersa. El tercer problema es la regularización e interpolación de modelos digitales de elevación imponiendo restricciones geométricas las cuales se extraen de una imagen de referencia. Para este problema se estudian tres modelos de regularización: un regularizador anisótropo de superficie mínima, la variación total anisótropa y un nuevo algoritmo de interpolación afín a trozos.
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26

Bäßler, Michael. "Untersuchungen zu Topographie und Bewegungsverhalten für das Küstengebiet des Riiser-Larsen- und Brunt-Schelfeises mittels Radarfernerkundung." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-70201.

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Mit der Weiterentwicklung von Sensoren und Methoden hat die Satellitenfernerkundung innerhalb der letzten 20 Jahre nicht nur einen großen Stellenwert in der Polarforschung errungen, sondern vor allem die Herangehensweisen an eine Vielzahl glaziologischer Probleme grundlegend verändert. RADAR-Sensoren (Radio Detection and Ranging) sind dabei besonders bei der Erkundung vereister Regionen hilfreich und tragen stark zur Ableitung klimasensitiver Parameter im Bereich der Antarktis bei. Nach einem einführenden Überblick im ersten wird im zweiten Kapitel mit Darstellungen zur Nutzung von RADAR-Messungen für Fernerkundungszwecke begonnen. Die zur Erhöhung der räumlichen Auflösung verwendete SAR-Prozessierung (Synthetic Aperture Radar) wird daraufhin kurz umrissen, bevor zu den Grundlagen der interferometrischen Auswertung (InSAR) übergeleitet wird. Bei dieser werden Phasendifferenzen unterschiedlicher Aufnahmen für Messzwecke eingesetzt. In den Beschreibungen wird aufgezeigt, wie sich derartige Messungen für die Ermittlung von Oberflächentopographie und Fließverhalten in polaren Regionen nutzen lassen. Eine Darstellung der ebenfalls benötigten Methoden zur Bestimmung von Verschiebungen in Bildpaaren und das Messprinzip der Laseraltimetrie beenden diesen Theorieteil. Das dritte Kapitel der Arbeit ist der Vorstellung des Arbeitsgebietes und der genutzten Datensätze gewidmet. Nach der geographischen Einordnung des Untersuchungsgebietes werden die wichtigsten glaziologischen Gegebenheiten vorgestellt. In der sich anschließenden Beschreibung genutzter Datensätze werden vor allem die für diese Region verfügbaren Höhen- und Ozeangezeitenmodelle intensiver besprochen. Die Bestimmung der Oberflächentopographie durch differentielle SAR-Interferometrie (DInSAR) ist Thema des vierten Kapitels. Nachdem die nötigen technischen Aspekte des Prozessierungsablaufes knapp erläutert wurden, werden die Unterschiede bei der Doppeldifferenzbildung benachbarter und identischer Wiederholspuren herausgearbeitet. Danach wird am Beispiel gezeigt, wie mithilfe von ICESat-Daten (Ice, Cloud and Land Elevation Satellite) eine Basislinienverbesserung zur genaueren Höhenbestimmung durchgeführt werden kann. Die ursprünglich separat abgeleiteten Höhenmodelle werden dann zu einer gemeinsamen Lösung kombiniert, welche abschließend hinsichtlich ihrer Genauigkeit besprochen und anderen Modellen vergleichend gegenübergestellt wird. Die Ableitung von Fließgeschwindigkeiten mit dem Hintergrund einer späteren Berechnung von Massenflüssen ist Gegenstand des fünften Kapitels, wobei drei unterschiedliche Methoden genutzt werden. Im ersten Fall wird das für RADAR-Bilder typische, hochfrequente Rauschen zur Bestimmung von Verschiebungen in ALOS-Daten (Advanced Land Observing Satellite) genutzt. Mit dieser Methode können durchgehende Fließgeschwindigkeitsfelder vom aufliegenden Bereich über die Aufsetzzone bis auf das Schelfeis ermittelt werden. DesWeiteren werden aus ERS-Daten (European Remote Sensing Satellite), die über einen Zeitraum von reichlich 13 Jahren vorliegen, Verschiebungen durch die Verfolgung von unveränderten, aber sich bewegenden Eisstrukturen bestimmt. Bei der als Drittes angewendeten, interferometrischen Methode werden aufsteigende und absteigende Satellitenspuren kombiniert, um die Fließinformationen zu rekonstruieren. In den jeweiligen Sektionen wird neben der Vorstellung der Ergebnisse auch deren Genauigkeit diskutiert. Das letzte große, sechste Kapitel untergliedert sich in zwei Teile. Im ersten dieser beiden Abschnitte wird gezeigt, wie InSAR und DInSAR zur Lagekartierung der Aufsetzzone eingesetzt werden können. Dabei werden die auf diese Weise ermittelten Ergebnisse dargestellt und diskutiert. Im zweiten, umfangreicheren Teil werden die zuvor gewonnenen Höhen- und Geschwindigkeitsinformationen genutzt, um deren Einfluss aus den InSAR-Messungen zu eliminieren, wodurch vertikale Höhenunterschiede mittels InSAR bestimmt werden können. Dies ist besonders für den Bereich der Aufsetzzone und des Schelfeises von Interesse, da diese Areale teilweise oder vollständig von Ozeangezeiten beeinflusst werden. Nach einer Luftdruckkorrektion werden den ermittelten Höhenunterschieden (entlang selektierter Profile) die Prädiktionen zwölf verfügbarer Ozeangezeitenmodelle gegenübergestellt. Die RMS-Werte dieser Differenzen werden abschließend genutzt, um die Qualität der Ozeangezeitenmodelle für die Region des Arbeitsgebietes einzustufen. Zum Abschluss werden in einer Zusammenfassung noch einmal die wichtigsten Ergebnisse aller Kapitel resümiert und bewertet<br>The development of new satellite sensors within the last 20 years along with changes towards more sophisticated processing strategies has not only given a new impetus to remote sensing data in view of polar research but also changed how a variety of glaciological problems are being addressed today. Particularly RADAR (radio detection and ranging) sensors are well-suited for the observation of glaciated areas and have already helped to retrieve a vast amount of climate sensitive parameters from the area of Antarctica. After an introductive overview at the beginning, the second chapter continues with the description of how RADAR measurements can be used to generate remote sensing images. The principle of synthetic aperture RADAR (SAR) which allows a better focusing of the RADAR measurements and therewith a rigorous increase of the spatial resolution of the images is outlined generally before more precise descriptions explain how interferometric SAR (InSAR) analyses can be used for the determination of surface topography heights and area-wide flow velocities. Two other techniques, namely matching methods for the determination of shifts between two images as well as the laser satellite altimetry are explained at the end of this chapter which closes the theoretical basics. The next section introduces the area of interest along with data sets which were used for validation purposes. After a careful exposure of the geographical situation, single objects such as ice streams and ice shelves are described in more detail. The following part, the data set introduction, has besides the description of other measurements its focus on topography and ocean tide models which are available for the area of investigation. Chapter four deals with the estimation of surface topography heights from differential InSAR (DInSAR) analyses. Therein the major differences for the usage of similar repeat tracks in contrast to neighboring, overlapping tracks will be shown and thoroughly discussed. The example of one track will be used to demonstrate how the required baseline estimation can be achieved if ICESat (Ice, Cloud and Land Elevation Satellite) profiles are used as tie points. Afterwards, all separately derived height models will be combined to obtain one final solution followed by an error analysis. A comparison to other available elevation models visualizes the spatial resolution of the derived model. The utilization of three different methods for the estimation of surface flow velocities (with the background of possible mass flux determinations) is the topic of the fifth chapter. The first case describes the usage of the high frequent noise contained in RADAR images for the tracking of horizontal surface displacements. Based on ALOS (Advanced Land Observing Satellite) data a flow velocity field which extends from the interior of the ice sheet across the grounding zone up to the ice shelf will be presented. Secondly, geocoded ERS (European Remote Sensing Satellite) images covering a time span of more than 13 years are used to track the motions of well-structured flat areas (ice shelf and glacier tongue). In the third approach used descending and ascending satellite passes will be combined in conjunction with a surface parallel flow assumption to interferometrically derive flow velocities in grounded areas. In each section respective errors will be discussed in order to evaluate the accuracy of the performed measurements. The last bigger chapter, number six, is divided into two sections. In the first one the adoption of SAR and InSAR with respect to the mapping of the grounding line location will be demonstrated. Results of the entire working area will be presented and compared to other data. The second section deploys the results of topography heights and flow velocities to remove both effects from the InSAR measurements which then allows to also measure height changes. This is of particular interest for the floating areas of ice shelf which are fully affected by ocean tides as well as for the grounding zone locations which partially experience deformations due to these height changes. After the correction for air pressure, changes between the image acquisitions, height changes along selected profiles are compared to twelve different ocean tide models. The RMS values of the differences are then used to evaluate the quality of these models for the working area. The most important results and conclusions are summarized in the last chapter
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27

Patiño, Quinchía Jorge Eduardo. "Cityscape, poverty and crime: a quantitative assessment using VHR imagery." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/59453.

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[EN] The first part of this work reviews the potential applications of satellite remote sensing to regional science research in urban settings. The availability of satellite remote sensing data has increased significantly in the last two decades. The increasing spatial resolution of commercial satellite imagery has influenced the emergence of new research and applications of regional science in urban settlements because it is now possible to identify individual objects of the urban fabric. The most common applications found in the literature are the detection of urban deprivation hot spots, quality of life index assessment, urban growth analysis, house value estimation, urban population estimation, urban social vulnerability assessment, and the variability of intra-urban crime rates. The satellite remote sensing imagery used in these applications has medium, high or very high spatial resolution (Landsat MSS, Landsat TM and ETM+, SPOT, ASTER, IRS, Ikonos and QuickBird). Consistent relationships between socio-economic variables derived from censuses and field surveys and proxy variables of vegetation coverage measured from satellite remote sensing data have been found in several cities in the US. Different approaches and techniques have been applied successfully around the world, but local research is always needed to account for the unique elements of each place. Spectral mixture analysis, object-oriented classifications and image texture measures are some of the techniques of image processing that have been implemented with good results. This work contributes empirical evidence about the usefulness of remote sensing imagery to quantify the degree of poverty at the intra-urban scale. This concept is based on two premises: first, that the physical appearance of an urban settlement is a reflection of the society; and second, that the people who reside in urban areas with similar physical housing conditions have similar social and demo- graphic characteristics. We evaluate the potential of the image-derived urban fabric descriptors to explain a measure of poverty known as the Slum Index. We found that these variables explain up to 59% of the variability in the Slum Index. Similar approaches could be used to lower the cost of socioeconomic surveys by developing an econometric model from a sample and applying that model to the rest of the city and to perform intercensal or intersurvey estimates of intra-urban Slum Index maps. The last part of this work analyzes the relation between the urban layout and crime. The link between place and crime is at the base of social ecology theories of crime that focus in the relationship of the characteristics of geographical areas and crime rates. The broken windows theory states that visible cues of physical and social disorder in a neighborhood can lead to an increase in more serious crime. Based on the premise that a settlement's appearance is a reflection of the society, we ask whether a neighbor- hood's design has a quantifiable imprint when seen from space using urban fabric descriptors computed from VHR imagery. The percentage of impervious surfaces other than clay roofs, the fraction of clay roofs to impervious surfaces, two structure descriptors related to the homogeneity of the urban layout, and the uniformity texture descriptor were all statistically significant. Areas with higher homicide rates tended to have higher local variation and less general homogeneity; that is, the urban layouts were more crowded and cluttered, with small dwellings with different roofing materials located in close proximity to one another, and these regions often lacked other homogeneous surfaces such as open green spaces, wide roads, or large facilities. These results seem to be in agreement with the broken windows theory and CPTED in the sense that more heterogeneous and disordered urban layouts are associated with higher homicide rates.<br>[ES] La primera parte aporta una revisión de las aplicaciones de la teledetección satelital en la investigación de ciencia regional en entornos urbanos. La disponibilidad de imágenes satelitales se ha incrementado significativamente en las dos últimas décadas, al tiempo que la resolución espacial ha venido aumentando, lo que ha influenciado el surgimiento de investigaciones y aplicaciones de ciencia regional en zonas urbanas. Las aplicaciones más comunes son la detección de hot spots de pobreza urbana, la evaluación de índices de calidad de vida, el análisis del crecimiento urbano, la estimación de valores de vivienda, la estimación de población urbana, la evaluación de la vulnerabilidad social y las variaciones intra-urbanas en tasas de crimen. Las imágenes satelitales usadas tienen resolución espacial media, alta o muy alta (Landsat MSS, Landsat TM y ETM+, SPOT, ASTER, IRS, Ikonos y Quickbird). Se han encontrado relaciones consistentes entre variables socio-económicas obtenidas de censos y encuestas y variables de la cobertura de vegetación en varias ciudades de Estados Unidos. Algunas de las técnicas que se han implementado y obtenido buenos resultados son el análisis de mezcla espectral, las clasificaciones orientadas a objetos y las medidas de textura de la imagen. Se aporta evidencia empírica acerca de la utilidad de las imágenes satelitales para cuantificar el grado de pobreza a escala intra-urbana. Se basa en dos premisas: primero, que la apariencia física de un asentamiento urbano es un reflejo de la sociedad que lo habita; y segundo, que la población de áreas urbanas con condiciones físicas de vivienda parecidas tiene características sociales y demográficas similares. Evaluamos el potencial de los descriptores del tejido urbano extraídos de la imagen para explicar una medida de pobreza conocida como el índice Slum. Encontramos que esas variables explican hasta un 59% de la variabilidad en el índice Slum. Aproximaciones similares a esta podrían usarse para disminuir el costo de encuestas socioeconómicas por medio del desarrollo de un modelo econométrico usando una muestra y luego aplicando el modelo al resto de la ciudad, y para elaborar estimaciones inter-censales o inter-encuestas de mapas intra-urbanos del índice Slum. La última parte analiza la relación entre el trazado urbano y crimen. El enlace entre el lugar y el crimen está en la base de las teorías socio-ecológicas de crimen que se enfocan en la relación de las características de las áreas geográficas y las tasas de crimen. La teoría de las ventanas rotas afirma que las evidencias visibles de desorden físico y social en un barrio pueden llevar al incremento de crímenes más serios. Con base en la premisa de que la apariencia de un asentamiento es un reflejo de la sociedad, nos preguntamos si el diseño del barrio tiene un impacto cuantificable cuando se observa desde el espacio usando descriptores del tejido urbano obtenidos de imágenes de muy alta resolución. El porcentaje de superficies impermeables diferentes a los techos de arcilla, la fracción de techos de arcilla sobre las superficies impermeables, dos variables de estructura relacionadas con la homogeneidad del trazado urbano y la variable de textura uniformidad resultaron estadísticamente significativas. Las áreas con tasas de homicidio más altas tienden a tener mayor variación local y menor homogeneidad general; esto es, los trazados urbanos son más desordenados y hacinados, con pequeñas viviendas que tienen materiales diferentes en sus techos localizadas muy cerca unas de otras, y estas áreas carecen a menudo de otras superficies homogéneas tales como espacios verdes abiertos, vías amplias y grandes construcciones industriales o institucionales. Estos resultados parecen estar en acuerdo con la teoría de las ventanas rotas y CPTED en el sentido de que los trazados urbanos más desordenados y heterogéneos están asociados con tasas de homicid<br>[CAT] La primera part aporta una revisió de les potencials aplicacions de la teledetecció espacial a la investigació en ciència regional en entorns urbans. La disponibilitat de dades de percepció remota des de satèl·lits s'ha incrementat significativament a les dues últimes dècades. La resolució espacial de les imatges de satèl·lit comercials també han anat augmentant i això, ha influït en l'aparició de investigacions i aplicacions a la ciència regional en assentaments urbans. Les aplicacions més comunes trobades a la literatura són la detecció de punts calents de pobresa urbana, l'avaluació dels índex de qualitat de vida, les anàlisis de creixement urbà, l'avaluació de la vulnerabilitat social i les variacions intraurbanes de les taxes de crims. Les imatges de satèl·lit emprades tenen resolució espacial mitjana, alta o molt alta (Landsat MSS, Landsat TM i ETM+, SPOT, ASTER, IRS, Ikonos y Quickbird). S'han torbat relacions consistents entre variables socioeconòmiques obtingudes de censos i enquestes i variables de la cobertura de vegetació en varies ciutats del Estats Units. Algunes de les tècniques que s'han implementat i han donat bons resultats són l'anàlisi de mescla espectral, les classificacions orientades a objecte i les mesures de textura de les imatges. Es aporta evidència empírica sobre la utilitat de les imatges de satèl·lit per quantificar el grau de pobresa a escala intraurbana. Es bassa en dues premisses: primer, que l'aparença física d'un assentament urbà n'és un reflex de la societat que l'habita; i segon, que les persones que resideixen en àrees urbanes amb condicions físiques de vivenda paregudes tenen també característiques socials i demogràfiques similars. Avaluem el potencial dels descriptors del teixit urbà extrets de la imatge per explicar una mesura de pobresa coneguda com index Slum. Trobem que aquestes variables expliquen fins un 59% de la variabilitat de l'índex Slum. Aproximacions semblants a aquesta es podrien emprar per a disminuir el cost de les enquestes socioeconòmiques mitjançant el desenvolupament d'un model economètric utilitzant una mostra i després aplicant el model a la resta de la ciutat, i per elaborar estimacions inter-censals o inter-enquestes de mapes intraurbans de l'índex Slum. La darrera part analitza la relació entre el traçat urbà i el crim. L'enllaç entre el lloc i el crim està a la base de les teories socio-ecològiques del crim que es centren en la relació de les característiques de les àrees geogràfiques i les taxes de crims. La teoria de les finestres trencades afirma que les evidències visibles de desordre físic i social d'un barri pot portar a l'augment de crims més greus. Basant-se en la premissa de que l'aparença d'un assentament n'és el reflex de la societat, ens hi preguntem si el disseny del barri té un impacte quantificable quan s'observa des de el espai, utilitzant descriptors del teixit urbà obtinguts de imatges de molt alta resolució. Han resultat estadísticament significatius el percentatge de superfícies impermeables diferents a les teulades de argila, la fracció de teulades d'argila sobre les superfícies impermeables, dues variables d'estructura relacionades amb la homogeneïtat del traçat urbà i la variable de textura de uniformitat. Les àrees amb taxes d'homicidi més altes tendeixen a presentar una major variació local i una menor homogeneïtat general; és a dir, el traçats urbans són més desordenats i amuntonats, amb petites vivendes que tenen materials diferents a les seues teulades localitzades molt prop unes d'altres, i aquestes àrees manquen sovint d'altres superfícies homogènies, com ara espais verds oberts, vies amplies i grans construccions industrials o institucionals. Aquests resultats pareixen estar-hi d'acord amb la teoria de les finestres trencades i CPTED en el sentit de que els traçats urbans més desordenats i heterogenis estan associats amb taxes d'homicides m<br>Patiño Quinchía, JE. (2015). Cityscape, poverty and crime: a quantitative assessment using VHR imagery [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59453<br>TESIS
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Sapena, Moll Marta. "Development and analysis of land-use/land-cover spatio-temporal metrics in urban environments: Exploring urban growth patterns and linkages to socio-economic factors." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/158626.

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[ES] Esta tesis aborda el desarrollo y análisis de nuevas herramientas y métodos para monitorizar y caracterizar el crecimiento urbano utilizando datos geográficos y bases de datos de usos y coberturas del suelo (LULC), así como explorar sus relaciones con factores socioeconómicos, aportando nuevas evidencias sobre el uso de los datos LULC para la caracterización urbana en diferentes niveles mediante métodos espaciales y estadísticos. En primer lugar, se compilaron e implementaron las métricas espacio-temporales más comunes dentro de una herramienta software, IndiFrag. A continuación, se presenta una metodología basada en métricas espacio-temporales y se propone un nuevo índice que cuantifica la desigualdad entre el crecimiento de la población y las zonas edificadas, para analizar y comparar los patrones de crecimiento urbano en diferentes niveles. Esto permitió una distinción de los patrones de crecimiento, además el análisis a diversos niveles contribuyó a una mejor comprensión de los patrones. En segundo lugar, se cuantificaron relaciones bidireccionales entre la estructura urbana de las ciudades y su situación socioeconómica a partir de métricas espaciales extraídas de mapas de zonas climáticas locales en 31 ciudades en Renania del Norte-Westfalia (Alemania). A partir de estos datos se cuantificaron relaciones con indicadores socioeconómicos mediante modelos de regresión lineal múltiple, explicando gran parte de su variabilidad. El método propuesto es transferible a otros conjuntos de datos, niveles y regiones. En tercer lugar, se evaluó el uso de las métricas espacio-temporales derivadas de los mapas LULC para identificar patrones espaciales de crecimiento urbano. Se utilizaron modelos de cambio de usos del suelo para simular diferentes escenarios de crecimiento urbano a largo plazo siguiendo varios patrones espaciales en diversas formas urbanas de partida. A continuación, se calcularon las métricas espacio-temporales para los escenarios simulados, se seleccionaron las más explicativas aplicando análisis discriminante y se clasificaron los patrones de crecimiento utilizando métodos estadísticos de agrupación. Por último, se identificaron relaciones empíricas entre indicadores socioeconómicos y su evolución a lo largo del tiempo con la estructura espacial de los elementos construidos y naturales en hasta 600 áreas urbanas de 32 países. Se aplicaron modelos de regresión random forest y las métricas espacio-temporales fueron capaces de explicar considerablemente la variabilidad de los indicadores socioeconómicos, confirmando que los patrones espaciales y sus cambios están vinculados a los indicadores socioeconómicos. Este trabajo contribuye a una mayor comprensión de los patrones de crecimiento urbano y amplía el conocimiento sobre las relaciones entre la estructura espacial urbana y los factores socioeconómicos. Se describen nuevos métodos para monitorizar y evaluar la sostenibilidad urbana a partir de bases de datos LULC, que podrían ser utilizadas por los investigadores, planificadores urbanos y responsables políticos para garantizar un futuro sostenible en los entornos urbanos.<br>[CAT] Aquesta tesi aborda el desenvolupament i l'anàlisi de noves ferramentes i mètodes per a monitorar i caracteritzar el creixement urbà utilitzant dades geogràfiques i bases de dades d'usos i cobertures del sòl (LULC), així com explorar les seues relacions amb factors socioeconòmics, i aportar noves evidències sobre la utilització de les dades LULC per a la caracterització urbana en diferents nivells mitjançant mètodes espacials i estadístics. En primer lloc, es van compilar i implementar mètriques espaciotemporals dins d'un programari, IndiFrag. A continuació, es presenta una metodologia basada en mètriques espaciotemporals i es proposa un nou índex que quantifica la desigualtat entre el creixement de la població i les zones edificades, i serveix per a analitzar i comparar els patrons de creixement urbà a diferents nivells. Això va permetre una distinció dels patrons de creixement, a més l'anàlisi a diversos nivells va contribuir a una millor comprensió dels patrons. En segon lloc, es van quantificar relacions bidireccionals entre l'estructura urbana de les ciutats i la seua situació socioeconòmica a partir de mètriques espacials extretes de mapes de zones climàtiques locals en 31 ciutats a Renània del Nord-Westfàlia (Alemanya). A partir d'aquestes dades es van quantificar relacions amb indicadors socioeconòmics mitjançant models de regressió lineal múltiple, explicant gran part de la seua variabilitat. El mètode proposat és transferible a altres conjunts de dades, nivells i regions. Seguidament, es va avaluar l'ús de les mètriques espaciotemporals derivades dels mapes LULC per a identificar patrons espacials de creixement urbà. Es van utilitzar models de canvi d'usos del sòl per a simular diferents escenaris de creixement urbà a llarg termini seguint diversos patrons espacials en diverses formes urbanes de partida. A continuació, es van calcular les mètriques espaciotemporals per als escenaris simulats, es van seleccionar les més explicatives aplicant anàlisi discriminant i es van classificar els patrons de creixement utilitzant mètodes estadístics d'agrupació. Finalment, es van identificar relacions empíriques entre indicadors socioeconòmics i la seua evolució al llarg del temps, amb l'estructura espacial dels elements construïts i naturals en fins a 600 àrees urbanes de 32 països. Es van aplicar models de regressió random forest i les mètriques van ser capaces d'explicar considerablement la variabilitat dels indicadors socioeconòmics, això confirma que els patrons espacials i els seus canvis estan vinculats als indicadors socioeconòmics. Aquest treball contribueix a una major comprensió dels patrons de creixement urbà i amplia el coneixement sobre les relacions entre l'estructura espacial urbana i els factors socioeconòmics. Es descriuen nous mètodes per a monitorar i avaluar la sostenibilitat urbana a partir de bases de dades LULC, que podrien ser utilitzades pels investigadors, planificadors urbans i responsables polítics per a garantir un futur sostenible en els entorns urbans.<br>[EN] This thesis addresses the development and analysis of new tools and methods for monitoring and characterizing urban growth using geo-data and land-use/land-cover (LULC) databases, as well as exploring their relationships with socio-economic factors, providing new evidences regarding the use of LULC data for urban characterization at different levels by means of spatial and statistical methods. First, the most common spatio-temporal metrics were compiled and implemented within a software tool, IndiFrag. Then, we present a methodology based on spatio-temporal metrics and propose a new index that quantifies the inequality of growth between population and built-up areas to analyze and compare urban growth patterns at different levels. This allowed for a differentiation of growing patterns, besides, the analysis at various levels contributed to a better understanding of such patterns. Second, we quantified the two-way relationship between the urban structure in cities and their socio-economic status by means of spatial metrics issued from a local climate zone map for 31 cities in North Rhine-Westphalia, Germany. Based on these data, we quantified their relationship with socio-economic indicators by means of multiple linear regression models, explaining a significant part of their variability. The proposed method is transferable to other datasets, levels, and regions. Third, we assessed the use of spatio-temporal metrics derived from LULC maps to identify urban growth spatial patterns. We applied LULC change models to simulate different long-term scenarios of urban growth following various spatial patterns on diverse baseline urban forms. Then, we computed spatio-temporal metrics for the simulated scenarios, selected the most explanatory by applying a discriminant analysis and classified the growth patterns using clustering methods. Finally, we identified empirical relationships between socio-economic indicators and their change over time with the spatial structure of the built and natural elements in up to 600 urban areas from 32 countries. We employed random forest regression models and the spatio-temporal metrics were able to explain substantially the variability of socio-economic variables. This confirms that spatial patterns and their change are linked to socio-economic indicators. This work contributes to a better understanding of urban growth patterns and improves knowledge about the relationships between urban spatial structure and socio-economic factors, providing new methods for monitoring and assessing urban sustainability by means of LULC databases, which could be used by researchers, urban planners and decision-makers to ensure the sustainable future of urban environments.<br>Sapena Moll, M. (2020). Development and analysis of land-use/land-cover spatio-temporal metrics in urban environments: Exploring urban growth patterns and linkages to socio-economic factors [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158626<br>TESIS
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Sánchez, García Elena. "Photogrammetry and image processing techniques for beach monitoring." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/123956.

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[ES] Las playas son ambientes ecológicos sumamente valiosos donde a lo largo de una frágil franja de transición converge el entorno terrestre y el medio marino. Durante el último siglo, la mejora en la comprensión de los procesos físicos que ocurren en la zona costera se ha convertido en un asunto de máxima importancia. Para abordar una planificación coherente de la gestión costera se requiere tomar en consideración el dinamismo de los diferentes cambios morfológicos que caracterizan estos ambientes a distintas escalas espaciales y temporales. El límite tierra-agua varía en función de la posición del nivel del mar y de la forma del perfil de playa que continuamente queda modelado por las olas incidentes. Intentar modelizar la respuesta de un paisaje tan voluble geomorfológicamente como las playas requiere disponer de múltiples medidas registradas con suficiente precisión para poder reconocer su respuesta frente a la acción de los distintos agentes geomórficos. Para ello resulta esencial disponer de diferentes sistemas de monitorización capaces de registrar de forma sistemática la línea de costa con exactitud y efectividad. Se requieren nuevos métodos y herramientas informáticas que permitan capturar, caracterizar y analizar eficientemente la información con el objeto de obtener indicadores con significación geomorfológica de calidad. En esto radica el objetivo de la presente tesis doctoral, centrándose en el desarrollo de herramientas y procedimientos eficientes para la monitorización costera mediante el uso de imágenes satelitales y fotografías terrestres. El trabajo aporta soluciones de procesamiento de imágenes de satélite y fotogramétricas a científicos, ingenieros y gestores costeros, proporcionando resultados que evidencian la gran utilidad de estas técnicas viables y de bajo coste para la monitorización costera. Mediante ellas se puede convertir información pública existente y de libre acceso (imágenes satelitales, datos de video cámaras o fotografías de la ciudadanía) en datos de alta calidad para el monitoreo de los cambios morfológicos de las playas, y lograr así una consiguiente gestión sostenible de los recursos costeros.<br>[CAT] Les platges són ambients ecològics summament valuosos on al llarg d'una feble franja de transició convergeix l'entorn terrestre i el medi marí. En l'últim segle, la millora en la comprensió dels processos físics que ocorren en la zona costanera s'ha convertit en un assumpte de màxima importància. Per a abordar una planificació coherent de la gestió costanera es requereix prendre en consideració el dinamisme dels diferents canvis morfològics que caracteritzen aquests ambients a diferents escales espacials i temporals. El límit terra-aigua varia en funció de la posició del nivell del mar i de la forma del perfil de platja que contínuament queda modelat per les ones incidents. Intentar modelitzar la resposta d'un paisatge tan voluble geomorfològicament com les platges requereix disposar de múltiples mesures registrades amb suficient precisió per poder reconèixer la seua resposta enfront de l'acció dels diferents agents geomòrfics. Per tant, resulta essencial disposar de diferents sistemes de monitoratge capaços de registrar de forma sistemàtica la línia de costa amb exactitud i efectivitat. Es requereixen nous mètodes i eines informàtiques que permeten capturar, caracteritzar i analitzar eficientment la informació a fi d'obtindre indicadors amb significació geomorfològica de qualitat. En això radica l'objectiu de la present tesi doctoral, que es centra en el desenvolupament d'eines i procediments eficients per al monitoratge costaner mitjançant l'ús d'imatges de satèl·lit i fotografies terrestres. El treball aporta solucions de processament d'imatges de satèl·lit i fotogramètriques a científics, enginyers, polítics i gestors costaners, proporcionant resultats que evidencien la gran utilitat d'aquestes tècniques factibles i de baix cost per a la monitorització costanera. Mitjançant aquestes es pot convertir informació pública existent i de lliure accés (imatges de satèl·lit, dades de videocàmeres o fotografies de la ciutadania) en dades d'alta qualitat per al monitoratge dels canvis morfològics de les platges, i aconseguir així una consegüent gestió sostenible dels recursos costaners.<br>[EN] Beaches are extremely valuable ecological spaces where terrestrial and marine environments converge along a fragile transition strip. An improvement in our understanding of the physical processes that occur in the coastal zone has become increasingly important during the last century. To approach a coherent planning of coastal management it is necessary to consider the dynamism of the various morphological changes that characterize these environments at different spatial and temporal scales. The land-water boundary varies according to the sea level and the shape of a beach profile that is continuously modelled by incident waves. Attempting to model the response of a landscape as geomorphologically volatile as beaches requires multiple precise measurements to recognize responses to the actions of various geomorphic agents. It is therefore essential to have monitoring systems capable of systematically recording the shoreline accurately and effectively. New methods and tools are required to efficiently capture, characterize, and analyze information - and so obtain geomorphologically significant indicators. This is the aim of the doctoral thesis, focusing on the development of tools and procedures for coastal monitoring using satellite images and terrestrial photographs. The work brings satellite image processing and photogrammetric solutions to scientists, engineers, and coastal managers by providing results that demonstrate the usefulness of these viable and low-cost techniques. Existing and freely accessible public information (satellite images, video-derived data, or crowd-sourced photographs) can be converted into high quality data for monitoring morphological changes on beaches and thus help achieve a sustainable management of coastal resources.<br>Agradecer al Ministerio de Educación, Cultura y Deporte del Gobierno de España por la beca predoctoral FPU, y por las ayudas de movilidad concedidas, que han permitido que esta Tesis Doctoral fuera una realidad. También a los proyectos AICO/2015/098 y CGL2015-69906-R financiados respectivamente por la Generalitat Valenciana y por el Ministerio de Economía y Competitividad.<br>Sánchez García, E. (2019). Photogrammetry and image processing techniques for beach monitoring [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/123956<br>TESIS
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Kopczynski, Sarah E. "Satellite predictions of subglacial hydrology, and final collapse of twinned terrestrial-tidewater glaciers, Anchorage lowland, Alaska." 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3358107.

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"Remote Sensing and Modeling of Stressed Aquifer Systems and the Associated Hazards." Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.50435.

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abstract: Aquifers host the largest accessible freshwater resource in the world. However, groundwater reserves are declining in many places. Often coincident with drought, high extraction rates and inadequate replenishment result in groundwater overdraft and permanent land subsidence. Land subsidence is the cause of aquifer storage capacity reduction, altered topographic gradients which can exacerbate floods, and differential displacement that can lead to earth fissures and infrastructure damage. Improving understanding of the sources and mechanisms driving aquifer deformation is important for resource management planning and hazard mitigation. Poroelastic theory describes the coupling of differential stress, strain, and pore pressure, which are modulated by material properties. To model these relationships, displacement time series are estimated via satellite interferometry and hydraulic head levels from observation wells provide an in-situ dataset. In combination, the deconstruction and isolation of selected time-frequency components allow for estimating aquifer parameters, including the elastic and inelastic storage coefficients, compaction time constants, and vertical hydraulic conductivity. Together these parameters describe the storage response of an aquifer system to changes in hydraulic head and surface elevation. Understanding aquifer parameters is useful for the ongoing management of groundwater resources. Case studies in Phoenix and Tucson, Arizona, focus on land subsidence from groundwater withdrawal as well as distinct responses to artificial recharge efforts. In Christchurch, New Zealand, possible changes to aquifer properties due to earthquakes are investigated. In Houston, Texas, flood severity during Hurricane Harvey is linked to subsidence, which modifies base flood elevations and topographic gradients.<br>Dissertation/Thesis<br>Doctoral Dissertation Geological Sciences 2018
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"Reconstruction of a Tornado Disaster Employing Remote Sensing Techniques: A Case Study of the 1999 Moore, Oklahoma Tornado." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.8969.

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abstract: Remote sensing has demonstrated to be an instrumental tool in monitoring land changes as a result of anthropogenic change or natural disasters. Most disaster studies have focused on large-scale events with few analyzing small-scale disasters such as tornadoes. These studies have only provided a damage assessment perspective with the continued need to assess reconstruction. This study attempts to fill that void by examining recovery from the 1999 Moore, Oklahoma Tornado utilizing Landsat TM and ETM+ imagery. Recovery was assessed for 2000, 2001 and 2002 using spectral enhancements (vegetative and urban indices and a combination of the two), a recovery index and different statistical thresholds. Classification accuracy assessments were performed to determine the precision of recovery and select the best results. This analysis proved that medium resolution imagery could be used in conjunction with geospatial techniques to capture recovery. The new indices, Shortwave Infrared Index (SWIRI) and Coupled Vegetation and Urban Index (CVUI), developed for disaster management, were the most effective at discerning reconstruction using the 1.5 standard deviation threshold. Recovery rates for F-scale damages revealed that the most incredibly damaged areas associated with an F5 rating were the slowest to recover, while the lesser damaged areas associated with F1-F3 ratings were the quickest to rebuild. These findings were consistent for 2000, 2001 and 2002 also exposing that complete recovery was never attained in any of the F-scale damage zones by 2002. This study illustrates the significance the biophysical impact has on recovery as well as the effectiveness of using medium resolution imagery such as Landsat in future research.<br>Dissertation/Thesis<br>M.A. Geography 2011
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"GeoAI-enhanced Techniques to Support Geographical Knowledge Discovery from Big Geospatial Data." Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.53688.

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abstract: Big data that contain geo-referenced attributes have significantly reformed the way that I process and analyze geospatial data. Compared with the expected benefits received in the data-rich environment, more data have not always contributed to more accurate analysis. “Big but valueless” has becoming a critical concern to the community of GIScience and data-driven geography. As a highly-utilized function of GeoAI technique, deep learning models designed for processing geospatial data integrate powerful computing hardware and deep neural networks into various dimensions of geography to effectively discover the representation of data. However, limitations of these deep learning models have also been reported when People may have to spend much time on preparing training data for implementing a deep learning model. The objective of this dissertation research is to promote state-of-the-art deep learning models in discovering the representation, value and hidden knowledge of GIS and remote sensing data, through three research approaches. The first methodological framework aims to unify varied shadow into limited number of patterns, with the convolutional neural network (CNNs)-powered shape classification, multifarious shadow shapes with a limited number of representative shadow patterns for efficient shadow-based building height estimation. The second research focus integrates semantic analysis into a framework of various state-of-the-art CNNs to support human-level understanding of map content. The final research approach of this dissertation focuses on normalizing geospatial domain knowledge to promote the transferability of a CNN’s model to land-use/land-cover classification. This research reports a method designed to discover detailed land-use/land-cover types that might be challenging for a state-of-the-art CNN’s model that previously performed well on land-cover classification only.<br>Dissertation/Thesis<br>Doctoral Dissertation Geography 2019
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"Assessing Usable Ground and Surface Water Level Correlation Factors in the Western United States." Master's thesis, 2018. http://hdl.handle.net/2286/R.I.51704.

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abstract: The Western Continental United States has a rapidly changing and complex ecosystem that provides valuable resources to a large portion of the nation. Changes in social and environmental factors have been observed to be significantly correlated to usable ground and surface water levels. The assessment of water level changes and their influences on a semi-national level is needed to support planning and decision making for water resource management at local levels. Although many studies have been done in Ground and Surface Water (GSW) trend analysis, very few have attempted determine correlations with other factors. The number of studies done on correlation factors at a semi-national scale and near decadal temporal scale is even fewer. In this study, freshwater resources in GSW changes from 2004 to 2017 were quantified and used to determine if and how environmental and social variables are related to GSW changes using publicly available remotely sensed and census data. Results indicate that mean annual changes of GSW of the study period are significantly correlated with LULC changes related to deforestation, urbanization, environmental trends, as well as social variables. Further analysis indicates a strong correlation in the rate of change of GSW to LULC changes related to deforestation, environmental trends, as well as social variables. GSW slope trend analysis also reveals a negative trend in California, New Mexico, Arizona, and Nevada. Whereas a positive GSW trend is evident in the northeast part of the study area. GSW trends were found to be somewhat consistent in the states of Utah, Idaho, and Colorado, implying that there was no GSW changes over time in these states.<br>Dissertation/Thesis<br>Masters Thesis Geography 2018
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"Spatial Growth of Informal Settlements in Delhi and Factors Affecting Growth Rate; An Application of Remote Sensing." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.9111.

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abstract: Slum development and growth is quite popular in developing countries. Many studies have been done on what social and economic factors are the drivers in establishment of informal settlements at a single cross-section of time, however limited work has been done in studying their spatial growth patterns over time. This study attempts to study a sample of 30 informal settlements that exist in the National Capital Territory of India over a period of 40 years and identify relationships between the spatial growth rates and relevant factors identified in previous socio-economic studies of slums using advanced statistical methods. One of the key contributions of this paper is indicating the usefulness of satellite imagery or remote sensing data in spatial-longitudinal studies. This research utilizes readily available LANDSAT images to recognize the decadal spatial growth from 1970 to 2000, and also in extension, calculate the BI (transformed NDVI) as a proxy for the intensity of development for the settlements. A series of regression models were run after processing the data, and the levels of significance were then studied and compared to see which relationships indicated the highest levels of significance. It was observed that the change in BI had a higher strength of relationships with the change in independent variables than the settlement area growth. Also, logarithmic and cubic models showed the highest R-Square values than any other tested models.<br>Dissertation/Thesis<br>M.U.E.P. Environmental Design and Planning 2011
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"Constraining Source Models, Underlying Mechanisms, and Hazards Associated with Slow Slip Events: Insight from Space-Borne Geodesy and Seismology." Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.51612.

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abstract: The movement between tectonic plates is accommodated through brittle (elastic) displacement on the plate boundary faults and ductile permanent deformation on the fault borderland. The elastic displacement along the fault can occur in the form of either large seismic events or aseismic slip, known as fault creep. Fault creep mainly occurs at the deep ductile portion of the crust, where the temperature is high. Nonetheless, aseismic creep can also occur on the shallow brittle portion of the fault segments that are characterized by frictionally weak material, elevated pore fluid pressure, or geometrical complexity. Creeping segments are assumed to safely release the accumulated strain(Kodaira et al., 2004; Rice, 1992)(Kodaira et al., 2004; Rice, 1992)(Kodaira et al., 2004; Rice, 1992)(Kodaira et al., 2004; Rice, 1992)(Kodaira et al., 2004; Rice, 1992) on the fault and also impede propagation of the seismic rupture. The rate of aseismic slip on creeping faults, however, might not be steady in time and instead consist of successive periods of acceleration and deceleration, known as slow slip events (SSEs). SSEs, which aseismically release the strain energy over a period of days to months, rather than the seconds to minutes characteristic of a typical earthquake, have been interpreted as earthquake precursors and as possible triggering factor for major earthquakes. Therefore, understanding the partitioning of seismic and aseismic fault slip and evolution of creep is fundamental to constraining the fault earthquake potential and improving operational seismic hazard models. Thanks to advances in tectonic geodesy, it is now possible to detect the fault movement in high spatiotemporal resolution and develop kinematic models of the creep evolution on the fault to determine the budget of seismic and aseismic slip. In this dissertation, I measure the decades-long time evolution of fault-related crustal deformation along the San Andrea Fault in California and the northeast Japan subduction zone using space-borne geodetic techniques, such as Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR). The surface observation of deformation combined with seismic data set allow constraining the time series of creep distribution on the fault surface at seismogenic depth. The obtained time-dependent kinematic models reveal that creep in both study areas evolves through a series of SSEs, each lasting for several months. Using physics-based models informed by laboratory experiments, I show that the transient elevation of pore fluid pressure is the driving mechanism of SSEs. I further investigate the link between SSEs and evolution of seismicity on neighboring locked segments, which has implications for seismic hazard models and also provides insights into the pattern of microstructure on the fault surface. I conclude that while creeping segments act as seismic rupture barriers, SSEs on these zones might promote seismicity on adjacent seismogenic segments, thus change the short-term earthquake forecast.<br>Dissertation/Thesis<br>Doctoral Dissertation Geological Sciences 2018
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37

"A Spatial Statistical Framework for Evaluating Landscape Pattern and Its Impacts on the Urban Thermal Environment." Doctoral diss., 2016. http://hdl.handle.net/2286/R.I.39433.

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abstract: Urban growth, from regional sprawl to global urbanization, is the most rapid, drastic, and irreversible form of human modification to the natural environment. Extensive land cover modifications during urban growth have altered the local energy balance, causing the city warmer than its surrounding rural environment, a phenomenon known as an urban heat island (UHI). How are the seasonal and diurnal surface temperatures related to the land surface characteristics, and what land cover types and/or patterns are desirable for ameliorating climate in a fast growing desert city? This dissertation scrutinizes these questions and seeks to address them using a combination of satellite remote sensing, geographical information science, and spatial statistical modeling techniques. This dissertation includes two main parts. The first part proposes to employ the continuous, pixel-based landscape gradient models in comparison to the discrete, patch-based mosaic models and evaluates model efficiency in two empirical contexts: urban landscape pattern mapping and land cover dynamics monitoring. The second part formalizes a novel statistical model called spatially filtered ridge regression (SFRR) that ensures accurate and stable statistical estimation despite the existence of multicollinearity and the inherent spatial effect. Results highlight the strong potential of local indicators of spatial dependence in landscape pattern mapping across various geographical scales. This is based on evidence from a sequence of exploratory comparative analyses and a time series study of land cover dynamics over Phoenix, AZ. The newly proposed SFRR method is capable of producing reliable estimates when analyzing statistical relationships involving geographic data and highly correlated predictor variables. An empirical application of the SFRR over Phoenix suggests that urban cooling can be achieved not only by altering the land cover abundance, but also by optimizing the spatial arrangements of urban land cover features. Considering the limited water supply, rapid urban expansion, and the continuously warming climate, judicious design and planning of urban land cover features is of increasing importance for conserving resources and enhancing quality of life.<br>Dissertation/Thesis<br>Doctoral Dissertation Geography 2016
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Brun, Julien. "Investigating the Eco-Hydrological Impact of Tropical Cyclones in the Southeastern United States." Diss., 2013. http://hdl.handle.net/10161/8046.

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<p>Tropical Cyclones (TCs) intensity and frequency are expected to be impacted by climate change. Despite their destructive potential, these phenomena, which can produce heavy precipitation, are also an important source of freshwater. Therefore any change in frequency, seasonal timing and intensity of TCs is expected to strongly impact the regional water cycle and consequently the freshwater availability and distribution. This is critical, due to the fact that freshwater resources in the US are under stress due to the population growth and economic development that increasingly create more demands from agricultural, municipal and industrial uses, resulting in frequent over-allocation of water resources. </p><p>In this study we concentrate on monitoring the impact of hurricanes and tropical storms on vegetation activity along their terrestrial tracks and investigate the underlying physical processes. To characterize and monitor the spatial organization and time of recovery of vegetation disturbance in the aftermath of major hurricanes over the entire southeastern US, a remote sensed framework based on MODIS enhanced vegetation index (EVI) was developed. At the SE scale, this framework was complemented by a water balance approach to estimate the variability in hurricane groundwater recharge capacity spatially and between events. Then we investigate the contribution of TCs (season totals and event by event) to the SE US annual precipitation totals from 2002 to 2011. A water budget approach applied at the drainage basins scale is used to investigate the partitioning of TCs' precipitation into surface runoff and groundwater system in the direct aftermath of major TCs. This framework allows exploring the contribution of TCs to annual precipitation totals and the consequent recharge of groundwater reservoirs across different physiographic regions (mountains, coastal and alluvial plains) versus the fraction that is quickly evacuated through the river network and surface runoff. </p><p>Then a Land surface Eco-Hydrological Model (LEHM), combining water and energy budgets with photosynthesis activity, is used to estimate Gross Primary Production (GPP) over the SE US The obtained data is compared to AmeriFlux and MODIS GPP data over the SE United States in order to establish the model's ability to capture vegetation dynamics for the different biomes of the SE US. Then, a suite of numerical experiments is conducted to evaluate the impact of Tropical Cyclones (TCs) precipitation over the SE US. The numerical experiments consist of with and without TC precipitation simulations by replacing the signature of TC forcing by NARR-derived climatology of atmospheric forcing ahead of landfall during the TC terrestrial path. The comparison of these GPP estimates with those obtained with the normal forcing result in areas of discrepancies where the GPP was significantly modulated by TC activity. These areas show up to 10% variability over the last decade.</p><br>Dissertation
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39

"Understanding Open Spaces in an Arid City." Doctoral diss., 2011. http://hdl.handle.net/2286/R.I.14309.

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abstract: This doctoral dissertation research aims to develop a comprehensive definition of urban open spaces and to determine the extent of environmental, social and economic impacts of open spaces on cities and the people living there. The approach I take to define urban open space is to apply fuzzy set theory to conceptualize the physical characteristics of open spaces. In addition, a 'W-green index' is developed to quantify the scope of greenness in urban open spaces. Finally, I characterize the environmental impact of open spaces' greenness on the surface temperature, explore the social benefits through observing recreation and relaxation, and identify the relationship between housing price and open space be creating a hedonic model on nearby housing to quantify the economic impact. Fuzzy open space mapping helps to investigate the landscape characteristics of existing-recognized open spaces as well as other areas that can serve as open spaces. Research findings indicated that two fuzzy open space values are effective to the variability in different land-use types and between arid and humid cities. W-Green index quantifies the greenness for various types of open spaces. Most parks in Tempe, Arizona are grass-dominant with higher W-Green index, while natural landscapes are shrub-dominant with lower index. W-Green index has the advantage to explain vegetation composition and structural characteristics in open spaces. The outputs of comprehensive analyses show that the different qualities and types of open spaces, including size, greenness, equipment (facility), and surrounding areas, have different patterns in the reduction of surface temperature and the number of physical activities. The variance in housing prices through the distance to park was, however, not clear in this research. This dissertation project provides better insight into how to describe, plan, and prioritize the functions and types of urban open spaces need for sustainable living. This project builds a comprehensive framework for analyzing urban open spaces in an arid city. This dissertation helps expand the view for urban environment and play a key role in establishing a strategy and finding decision-makings.<br>Dissertation/Thesis<br>Ph.D. Geography 2011
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Ηλίας, Παναγιώτης. "Ground deformation observed in the western Corinth rift (Greece) by means of SAR interferometry." Thesis, 2013. http://hdl.handle.net/10889/7246.

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The rift of Corinth (Greece) has been long identified as a site of major importance in Europe due to its intense tectonic activity. It is one of the world’s most rapidly extending continental regions and it has one of the highest seismicity rates in the Euro-Mediterranean region. The GPS studies conducted since 1990 indicate a north–south extension rate across the rift of ~1.5 cm year-1 around its western termination. Geological evidences show that the south coast of the rift is uplifting whereas the north part is subsiding. The western termination of the rift in the Patras broader area, with many active faults lying very close and inside the city of Patras, presents major scientific and socio-economic importance. Recent seismicity has affected this end of the rift with the Movri (Achaia) earthquake in june 2008 and a seismic swarm around Efpalio (Fokida) in January 2010. Additionally the presence of a plurality of geophysical phenomena and morphological features renders this area and the Gulf of Corinth generally, as natural laboratory, a place of international initiatives as the Corinth Rift Laboratory and a case study for the EO Supersites initiative. Seismic and geodetic ground measurements from permanent networks (since 2000) and measuring campaigns (since 1990) have been (and are) performed. Moreover dense SAR data are available since 1992 and the ERS1 mission. Motivated by the lack of precise and extended mapping of the vertical deformation of the area and by the limitations of the GPS network (in terms of density of points) we investigate, model and interpret a large set of SAR interferometry data completed by the GPS data. The SAR interferometry data are very powerful for measuring vertical motions, for mapping localized deformations across faults or other features and for mapping and modeling the co-seismic deformation produced by earthquakes. We processed ascending and ascending acquisitions of ASAR/ENVISAT in the period between 2002-2010, to produce Persistent Scatterrers and Small Baseline Subsets deformation rates maps. These products have been combined together but also constrained with a number of GPS observations in order to extract the precise Up-Down and East-West deformation components field. The methodology chain performed globally well over the area (despite the vegetation cover and slopes) and provides accurate and robust results in many areas. We verified the agreement between GPS and the InSAR deformation field rates. We also compared them with remote sensing and ground observations of independent studies. We focused in specific case studies and presented the deformation rates along cross sections inside the city of Patras, around the Rion-Antirion bridge, around the urban areas of Psathopyrgos, Aigion, Sellianitika, Nafpaktos, Ακratas, the island of Trizonia, and the river deltas of Psathopyrgos, Sellianitika, Aigion, Mornos, Marathias and Akrata. Significant ground deformation is observed within the city of Patras itself, due not only to urban subsidence often seen elsewhere, but also to the motion of shallow structures likely to be induced by deep tectonic movements at the junction of the right lateral strike-slip fault linked to the Movri and penetrating inland between Rio and Patras (trans-tensional fault of Rio Patras), and the Psathopirgos normal fault at the entrance of the Corinth Rift. The Rio-Patras fault is a transition, oblique, structure, connecting the strike-slip zone to the south and the extentional area to the east. The Aigion fault appears very active with uplift rate of about 2mm/an, the highest rate across the Corinth Rift in the sample period, this uprising damping in the three kilometers separating this fault from the West Helike fault to the south. The observed discontinuities of the deformation field are not always correlated with seismic activity at the same place in the sampled period. The Temeni-Valimitika delta, east of Aigion, is the only delta of the area not subsiding (at least at its bigger part). We think that this is because it is located on the footwall of the Aigion fault with the delta compaction/subsidence balanced by the tectonic uplift. All the other deltas are subsiding due to the compaction of their sediments, and in the big ones it is possible to observe a linear increasing rate as approaching their coastal borders. The 2008 and 2010 seismic events occurred in the study area are modeled by inversion of their sources parameters using a model of dislocation in an homogenous elastic half-space constrained by the seismic, the GPS and the SAR interferometry data. At the broad scale, most of our studied tectonic features are pieces of a (diffuse) triple junction between micro-plates at the boundary between the rift of Corinth to the east and the termination of the Hellenic arc to the west. We briefly investigated and discuss the Trikonida and Aitoliko valley deformation field in the northwest of the triple junction area. Finally for the sake of completeness and in order to assess the capabilities of the space geodesy we presented some inferred discontinuities occurred by landslides and some by unclear origin and requiring further investigations.<br>Η ρηξιγενής ζώνη της Κορίνθου (Ελλάδα) έχει από καιρό αναγνωριστεί ως μια περιοχή μείζονος σημασίας στην Ευρώπη, λόγω της έντονης τεκτονικής της δραστηριότητας. Είναι μία από τις πιο ταχέως εφελκούμενες ηπειρωτικές περιοχές στον κόσμο και παρουσιάζει ένα από τους υψηλότερους ρυθμούς σεισμικότητας στον Ευρω-μεσογειακό χώρο. Μελέτες GPS που διεξάγονται από το 1990 εκτιμούν το ρυθμό εφελκυσμού περί τα 1.5 εκατοστά ανά έτος γύρω στο δυτικό πέρας του. Γεωλογικές μελέτες δείχνουν ότι η νότια ακτή του ανυψώνεται, ενώ η βόρεια υποχωρεί. Το δυτικό πέρας της ρηξιγενής ζώνης στην ευρύτερη περιοχή της Πάτρας, με πολλά ενεργά ρήγματα που βρίσκονται πολύ κοντά και μέσα στην πόλη, παρουσιάζει σημαντικές επιστημονικές και κοινωνικο-οικονομικές προεκτάσεις. H πρόσφατη σεισμικότητα έχει εκδηλωθεί σε αυτή τη περιοχή με τον σεισμό της Μόβρης (Αχαΐα) τον Ιούνιου του 2008 και της σεισμικής ακολουθίας κοντά στο Ευπάλιο (Φωκίδα) τον Ιανουάριο του 2010. Επιπλέον, η παρουσία ενός πλήθους γεωφυσικών φαινομένων και γεωμορφολογικών χαρακτηριστικών καθιστά την εν λόγω περιοχή, αλλά και τον Κορινθιακό Κόλπο εν γένει, ένα φυσικό εργαστήριο, μια περιοχή μελέτης για διεθνείς πρωτοβουλίες, όπως το Corinth Rift Laboratory και μια περιπτωσιολογική μελέτη της πρωτοβουλίας ‘EO Supersites’. Σεισμικές και γεωδαιτικές επιτόπιες παρατηρήσεις, από μόνιμα δίκτυα (από το 2000), και δειγματοληπτικές μετρήσεις (από το 1990), συνεχίζονται να διενεργούνται από το 2000 και 1990 αντίστοιχα. Επιπλέον πυκνές λήψεις δεδομένων SAR είναι διαθέσιμες από το 1992 από την αποστολή του ERS-1. Παρακινούμενοι από την έλλειψη μιας λεπτομερούς, ακριβούς και εκτεταμένης χαρτογράφησης της κάθετης παραμόρφωσης στην περιοχή ενδιαφέροντος και τους περιορισμούς του δικτύου GPS (από την άποψη της πυκνότητας της δειγματοληψίας), ερευνούμε, μοντελοποιούμε και ερμηνεύουμε ένα μεγάλο σύνολο δεδομένων διαφορικής συμβολομετρίας SAR και μετρήσεων GPS. Τα δεδομένα διαφορικής συμβολομετρίας μπορούν να αξιοποιηθούν για την ακριβή μέτρηση κατακόρυφων μετακινήσεων, για τη χαρτογράφηση τοπικών παραμορφώσεων εκατέρωθεν ρηγμάτων ή άλλων σχηματισμών και για τη χαρτογράφηση και μοντελοποίηση της ενδο-σεισμικής παραμόρφωσης. Επεξεργαστήκαμε δεδομένα ανοδικής και καθοδικής τροχιάς του δέκτη ASAR / ENVISAT της περιόδου μεταξύ 2002-2010, για την παραγωγή χαρτών ρυθμού παραμόρφωσης Σταθερών Σκεδαστών (Persistent Scatterrers) και υποσύνολα μικρών χωρικών γραμμών βάσης (Small Baseline Subsets – SBAS). Τα προϊόντα συνδυάστηκαν κατάλληλα, αλλά και διορθώθηκαν από μια σειρά από παρατηρήσεις GPS, προκειμένου να εξαχθεί το ακριβές πεδίο παραμόρφωσης κατά την κατακόρυφη και κατά την διεύθυνση Ανατολής-Δύσης συνιστώσα. Η ακολουθούμενη μεθοδολογία λειτούργησε καλά σε ευρεία κλίμακα στην περιοχή ενδιαφέροντος (παρά την κάλυψη της βλάστησης και το έντονο ανάγλυφο) και παρείχε ακριβείς και αξιόπιστες εκτιμήσεις σε πολλές επί μέρους περιοχές. Επαληθεύσαμε τη συμφωνία μεταξύ των πεδίων παραμόρφωσης των παρατηρήσεων GPS και συμβολομετρίας. Επίσης τα συγκρίναμε με δεδομένα τηλεπισκόπησης και επίγειες παρατηρήσεις από ανεξάρτητες μελέτες. Εστιάσαμε σε συγκεκριμένες περιπτωσιολογικές μελέτες και παρουσιάσαμε τους ρυθμούς παραμόρφωσης μαζί με διατομές μέσα στην πόλη της Πάτρας, γύρω από τη γέφυρα Ρίου-Αντιρρίου, γύρω από τις αστικές περιοχές του Ψαθόπυργου, Αίγιου, Σελλιανίτικων, Ναυπάκτου, Ακράτας, νήσου Τριζονίων, και τα ποτάμια δέλτα του Ψαθόπυργου, Σελλιανίτικων, Αιγίου, Μόρνου, Μαραθιά και Ακράτας. Σημαντική παραμόρφωση του εδάφους παρατηρείται μέσα στην πόλη της Πάτρας, οφειλόμενη όχι μόνο στην αστική καθίζηση (όπως συμβαίνει συχνά), αλλά και στην μετακίνηση των ρηχών δομών που ενδέχεται να προκαλούνται από βαθιές τεκτονικές μετακινήσεις στην επαφή του δεξιόστροφου ρήγματος πλευρικής ολίσθησης που συνδέεται με τον σεισμό της Μόβρης. Το τελευταίο διεισδύει στη ξηρά και συνδέεται μεταξύ Ρίου και Πάτρας (ρήγμα πλάγιας ολίσθησης) και στη συνέχεια με το κανονικό ρήγμα του Ψαθόπυργου στην είσοδο της ρηξιγενής ζώνης της Κορίνθου. Το ρήγμα Ρίου-Πάτρας αποτελεί μια ζώνη μετάβασης, συνδέοντας την ζώνη πλευρικής ολίσθησης στο Νότο με τις ρηξιγενείς δομές εφελκυσμού στην Ανατολή. Το ρήγμα του Αιγίου παρουσιάζει υψηλή ενεργητικότητα με ρυθμό ανύψωσης περί τα 2 χιλιοστά ανά έτος, ο υψηλότερος στην ρηξιγενή ζώνη της Κορίνθου κατά την περίοδο δειγματοληψίας, ο οποίος αποσβένει στα τρία χιλιόμετρα που χωρίζουν αυτό το ρήγμα με το Δυτικό τμήμα του ρήγματος της Ελίκης στο νότο. Οι παρατηρούμενες ασυνέχειες του πεδίου παραμόρφωσης δεν σχετίζονται πάντα με τη σεισμική δραστηριότητα κατά την περίοδο της μελέτης. Το δέλτα της Τέμενης-Βαλιμίτικων, ανατολικά του Αιγίου, είναι το μόνο δέλτα της περιοχής που δεν υποχωρεί (τουλάχιστον κατά τη μεγαλύτερη έκτασή του). Πιστεύουμε ότι αυτό οφείλεται στο ότι βρίσκεται στο πόδα του ρήγματος του Αιγίου με την συμπίεση/καθίζηση του δέλτα να εξισώνεται με την τεκτονική ανύψωση. Όλα τα άλλα δέλτα υποχωρούν λόγω της συμπίεσης των ιζημάτων τους, και στα μεγαλύτερα είναι δυνατόν να παρατηρηθεί ένας γραμμικώς αυξανόμενος ρυθμός παραμόρφωσης καθώς προσεγγίζουμε το προδέλτα του. Τα σεισμικά γεγονότα του 2008 και 2010 που έλαβαν χώρα στην περιοχή μελέτης μοντελοποιήθηκαν με αναστροφή των παραμέτρων της πηγής παραμόρφωσής τους, χρησιμοποιώντας ένα μοντέλο της μετατόπισης σε ένα ομογενές ελαστικό ημίχωρικό μέσο με χρήση σεισμικών, GPS και συμβολομετρικών δεδομένων. Σε ευρεία κλίμακα, οι περισσότερες υπό μελέτη τεκτονικές δομές αποτελούν τμήματα μιας (διάχυτης) τριπλής επαφής μεταξύ των μικρο-πλακών στο όριο ανάμεσα στη ρηξιγενή ζώνη της Κορίνθου στα Ανατολικά και στον τερματισμό του Ελληνικού τόξου προς τα δυτικά. Ερευνήσαμε συνοπτικά και συζητήσαμε το πεδίο παραμόρφωσης της λίμνης Τριχωνίδας και της κοιλάδας του Αιτολικού στα βορειοδυτικά της περιοχής της τριπλής επαφής. Τέλος, χάρη πληρότητας και για την αξιολόγηση των δυνατοτήτων της διαστημικής γεωδαισίας παρουσιάσαμε μερικές ασυνέχειες οι οποίες άλλες προκλήθηκαν από κατολισθήσεις και άλλες με ασαφή προέλευση οι οποίες χρήζουν περαιτέρω έρευνας.
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41

"West Nile virus in Maricopa County, Arizona: Investigating human, vector, and environmental interactions." Master's thesis, 2013. http://hdl.handle.net/2286/R.I.18663.

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abstract: Despite the arid climate of Maricopa County, Arizona, vector-borne diseases have presented significant health challenges to the residents and public health professionals of Maricopa County in the past, and will continue to do so in the foreseeable future. Currently, West Nile virus is the only mosquitoes-transmitted disease actively, and natively, transmitted throughout the state of Arizona. In an effort to gain a more complete understanding of the transmission dynamics of West Nile virus this thesis examines human, vector, and environment interactions as they exist within Maricopa County. Through ethnographic and geographic information systems research methods this thesis identifies 1) the individual factors that influence residents' knowledge and behaviors regarding mosquitoes, 2) the individual and regional factors that influence residents' knowledge of mosquito ecology and the spatial distribution of local mosquito populations, and 3) the environmental, demographic, and socioeconomic factors that influence mosquito abundance within Maricopa County. By identifying the factors that influence human-vector and vector-environment interactions, the results of this thesis may influence current and future educational and mosquito control efforts throughout Maricopa County.<br>Dissertation/Thesis<br>M.S. Sustainability 2013
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42

Donner, Ralf. "Die visuelle Interpretation von Fernerkundungsdaten." Doctoral thesis, 2007. https://tubaf.qucosa.de/id/qucosa%3A22626.

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Die Fähigkeit, in Luft- und Satellitenbildern Objekte wiederzuerkennen, kann folgendermaßen erklärt werden: Aus der Kenntnis einer Landschaft und ihrer Abbildung im Bild werden Interpretationsregeln entwickelt, die bestimmten Kombinationen von Bildmerkmalen wie Farbe, Form, Größe, Textur oder Kontext festgelegte Bedeutungen zuordnen. Kommt es nicht auf das Wiedererkennen mit festen Wahrnehmungsmustern an, stellt sich die bislang offene Frage nach einer wissenschaftlichen Kriterien genügenden Methode, wie der gedankliche Zusammenhang zwischen den Sinneswahrnehmungen erfasst werden kann. Die Erfahrung von Umkehrbildern und optischen Täuschungen führt zur Frage nach dem festen Element bei der visuellen Interpretation von Fernerkundungsdaten. Galileis Antwort, Messwerte als Ausgangspunkt naturwissenschaftlicher Erkenntnis zu nehmen, löst die Mehrdeutigkeiten und Unsicherheiten gedanklicher Interpretationen nicht auf, denn zu jeder Zahl gehört bereits eine gedankliche Bestimmung darüber, was sie bedeutet: Äpfel, Birnen, Höhendifferenzen … Daher muss für die begriffliche Interpretation der Wahrnehmungen ein anderer Ausgangspunkt bestimmt werden: Weder kann der Mensch beobachten oder wahrnehmen, ohne seine Erlebnisse gedanklich zu fassen und zu ordnen, noch ist die Sinnesempfindung ein subjektives, vom Gegenstand abgespaltenes, nur persönliches Erlebnis. Wahrnehmung realisiert sich als Einheit von Wahrnehmendem und Wahrgenommenen. Demzufolge gibt es keine binäre Unterscheidung von objektiver Tatsache und subjektiver Interpretation. Wahrnehmung findet zwischen den Polen reiner Empfindung eines gegebenen und sinnlichkeitsfreien Denkens statt. Die reinen Erlebnisqualitäten der Sinnesempfindungen (warm, kalt, hell, rau) stellen sich als die am wenigsten von der subjektiven gedanklichen Interpretation abhängigen Elemente des Erkenntnisprozesses dar. Diesem Verhältnis von Beobachtung und gedanklicher Deutung entspricht ein phänomenologischer Untersuchungsansatz. Mit ihm bekommen Erfahrungen als absolute Elemente der Wahrnehmung primäre Bedeutung, gedankliche Interpretationen werden zu Abhängigen. Daher werden in der Untersuchung Ergebnisse phänomenologischer Arbeiten bevorzugt. Auch die eigene Bearbeitung des Themas geht von einer konsequent empirischen Position aus. Um einen Sachverhalt zu verstehen, genügt es nicht, bei den Sinnesempfindungen stehen zu bleiben, denn zu ihrem Verständnis fehlt der gedankliche Zusammenhang, die Erlebnisse müssen begrifflich interpretiert werden. Dabei ist die Doppelrolle der Begriffe von entscheidender Bedeutung: In der Analyse grenzen sie innerhalb des Erfahrungsfeldes Teilaspekte gegeneinander ab, welche in der Synthese durch dieselben Begriffe gedanklich verbunden werden. Diese Funktion der Begriffe wird ausgenutzt, um Wiedererkennen und Bildung von Verständnis zu differenzieren: Die Interpretation der Erfahrung nach a priori vorgegebenen Mustern zielt auf das Wiedererkennen. Im Gegensatz dazu emergiert Verständnis im Prozess der Begriffsbildung aus den Beobachtungen: Man sucht erst nach einer Gliederung, welche eine gedankliche Synthese plausibel erscheinen lässt. Das Konzept der Selbstorganisation hat in der Ökologie mechanistische Vorstellungen weitgehend abgelöst und im letzten Jahrzehnt auch in die Technik Eingang gefunden. Mit den Worten dieses Konzeptes kann die Begriffsbildung als Erkenntnisprozess beschrieben werden, in welchem sich gedankliche und nichtgedankliche Wahrnehmungen selbst organisieren. Sinnesempfindungen haben auch in anderen Zugangsweisen zur Natur eine dominierende Stellung. Daher können Goetheanismus, wissenschaftliche Ästhetik und Kunst zu einer voraussetzungslosen Naturerkundung beitragen. Die nahe Verwandtschaft von Phänomenologie, Ästhetik und Kunst lässt künstlerisches Schaffen als Vervollkommnung des in der Natur Veranlagten erscheinen. Weitere Querbeziehungen ergeben sich aus der Interpretation topografischer oder thematischer Karten oder sonstiger visualisierter raumbezogener Daten. Parallelen und Unterschiede werden herausgearbeitet. Moderne Naturwissenschaft ist quantitativ. Daher ist zu klären, was mathematische Modellierung zur Verständnisbildung beiträgt. In diesem Teil der Arbeit ist es der folgende Gedanke, welcher über die hinlänglich bekannte Nützlichkeit mathematischer Modellierungen, Vorausberechnungen und Simulationen hinausgeht: Die Mathematik überzeugt durch ihre logische Strenge in der Ableitung und Beweisführung: Aus Obersatz und Untersatz folgt die Konklusion. Eine Beobachtungsmethode, bei welcher eine Beobachtung an die nächste gereiht wird, so dass sich das Eine aus dem Anderen ergibt, wobei kein Sprung die Folge unterbricht, käme der Notwendigkeit eines mathematischen Beweises gleich. Diese strenge Folge des Einen aus dem Anderen tritt in der wissenschaftlichen Argumentation an die Stelle der spontanen Intuition mit Verifikation, Falsifikation und bestätigendem Beispiel. Auf diese Weise kann durch die Anwendung der mathematischen Methode eine realitätsnahe Begriffsbildung erreicht werden. Die bis hierher dargelegten Aspekte der Wahrnehmung, der Ästhetik, der Kunst und der Mathematik werden in der Methode einer voraussetzungslosen Begriffsentwicklung zusammengefasst. Damit ist das Hauptziel der Untersuchung, die Entwicklung einer auf das Verständnis gerichteten erfahrungsbasierten Beobachtungsmethode, erreicht. Die Abhandlung wird mit der Anwendung der entwickelten Methode auf einen Grundbegriff der Geoinformatik in folgender Weise fortgesetzt: Für die Geoinformatik ist der Raumbegriff von grundlegender Bedeutung. Daher bietet es sich an, diesen Begriff unter Anwendung der entwickelten Methode zu untersuchen. Unter phänomenologischen Gesichtspunkten stehen Raum und Zeit in einem engen Zusammenhang. Beide werden in der Bewegung erfahren. Interpretiert man Bewegung mit den Begriffen des Nebeneinander und des Nacheinander, entsteht Wissen von Raum und Zeit. Mit anderen Worten: Die am Leib erfahrene Bewegung wird durch Interpretation mit dem Raumbegriff zur Vorstellung durchlaufener Orte. Je nachdem, welche Sinneserfahrungen, allgemeiner: Beobachtungen, zugrunde gelegt werden, hat der Raum unterschiedliche geometrische Eigenschaften. Die Erfahrungen des Tastsinnes begründen euklidische Beobachtungen. Die Begriffe Raum und Zeit haben für die Verständnisbildung eine fundamentale Bedeutung. Mit ihrer Hilfe können die Erlebnisse als zugleich und nebeneinander oder als nacheinander geordnet werden. Sie ermöglichen Erkenntnis durch Analyse und Synthese. Wesentliches Motiv der Untersuchung ist die Frage nach der Bildung von Verständnis im Rahmen der visuellen Interpretation. Das Erkennen von Objekten stellt sich als synästhetische Synthese der Sinnesempfindungen und gedanklicher Inhalte dar. Unterschiedliche Gewichtungen der Gedankeninhalte lassen zwei Vorgehensweisen unterscheiden: 1, Für das Erkennen von Neuem ist es von grundlegender Bedeutung, dass die gedanklichen Inhalte den nichtgedanklichen Sinnesempfindungen untergeordnet sind, das heißt von diesen modifiziert werden können. Vorgewussten Begriffen kommt die Rolle von Hypothesen zu. 2, Beim Wiedererkennen haben gedankliche Inhalte eine dominierende Rolle – anhand von Interpretationsmerkmalen sollen Bildinhalten Bedeutungen zugewiesen werden. Das Bild wird hierzu nach Bildflächen mit solchen Kombinationen von Farben, Formen, Mustern, Texturen und räumlichen Anordnungen durchsucht, die dem zu suchenden Begriff entsprechen können. Oder das Bild wird, bei Verwendung einer Art Beispielschlüssel, nach Übereinstimmungen mit kompletten Bildmustern durchsucht. Auch das ist eine Form des Wiedererkennens. Um ein Phänomen zu verstehen, kommt es darauf an, in der Regelmäßigkeit der äußeren Form den Zusammenhang zu entdecken, der den verschiedenartigen Ausgestaltungen als regelndes Element zugrunde liegt. Dazu muss über eine Klassifizierung von Interpretationsmerkmalen hinausgegangen werden. Die gedankliche Auseinandersetzung mit den visualisierten Repräsentanzen der Phänomene unterstützt die Bildung eines solchen ideellen Zusammenhangs, welcher das in aller Mannigfaltigkeit der natürlichen Erscheinungen Gleichbleibende, Ruhende darstellt, aus welchem die Einzelphänomene hervorgegangen sein könnten. Die Funktionen beschreiben die Wechselwirkungen zwischen den räumlichen Elementen, welche sich in Austauschprozessen von Energie, Material und Stoffen ausdrücken. Überall dort, wo räumliche Anordnung ein Ausdruck funktionaler Beziehungen ist, unterstützt die visuelle Wahrnehmung der räumlichen Beziehungen die Einsicht in die sachlichen. In den Schlussfolgerungen wird die Visualisierung von Geodaten als Mittel zur Sichtbarmachung des Zusammenhanges zwischen den Erscheinungen charakterisiert. Die Bezugnahme zur Fernerkundung führt zu der Feststellung, dass die Anwendung der vorgeschlagenen Forschungsstrategie im Bereich der Geofernerkundung nur eingeschränkt möglich ist.
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43

Bäßler, Michael. "Untersuchungen zu Topographie und Bewegungsverhalten für das Küstengebiet des Riiser-Larsen- und Brunt-Schelfeises mittels Radarfernerkundung: Untersuchungen zu Topographie und Bewegungsverhalten für das Küstengebiet des Riiser-Larsen- und Brunt-Schelfeises mittels Radarfernerkundung." Doctoral thesis, 2010. https://tud.qucosa.de/id/qucosa%3A25606.

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Abstract:
Mit der Weiterentwicklung von Sensoren und Methoden hat die Satellitenfernerkundung innerhalb der letzten 20 Jahre nicht nur einen großen Stellenwert in der Polarforschung errungen, sondern vor allem die Herangehensweisen an eine Vielzahl glaziologischer Probleme grundlegend verändert. RADAR-Sensoren (Radio Detection and Ranging) sind dabei besonders bei der Erkundung vereister Regionen hilfreich und tragen stark zur Ableitung klimasensitiver Parameter im Bereich der Antarktis bei. Nach einem einführenden Überblick im ersten wird im zweiten Kapitel mit Darstellungen zur Nutzung von RADAR-Messungen für Fernerkundungszwecke begonnen. Die zur Erhöhung der räumlichen Auflösung verwendete SAR-Prozessierung (Synthetic Aperture Radar) wird daraufhin kurz umrissen, bevor zu den Grundlagen der interferometrischen Auswertung (InSAR) übergeleitet wird. Bei dieser werden Phasendifferenzen unterschiedlicher Aufnahmen für Messzwecke eingesetzt. In den Beschreibungen wird aufgezeigt, wie sich derartige Messungen für die Ermittlung von Oberflächentopographie und Fließverhalten in polaren Regionen nutzen lassen. Eine Darstellung der ebenfalls benötigten Methoden zur Bestimmung von Verschiebungen in Bildpaaren und das Messprinzip der Laseraltimetrie beenden diesen Theorieteil. Das dritte Kapitel der Arbeit ist der Vorstellung des Arbeitsgebietes und der genutzten Datensätze gewidmet. Nach der geographischen Einordnung des Untersuchungsgebietes werden die wichtigsten glaziologischen Gegebenheiten vorgestellt. In der sich anschließenden Beschreibung genutzter Datensätze werden vor allem die für diese Region verfügbaren Höhen- und Ozeangezeitenmodelle intensiver besprochen. Die Bestimmung der Oberflächentopographie durch differentielle SAR-Interferometrie (DInSAR) ist Thema des vierten Kapitels. Nachdem die nötigen technischen Aspekte des Prozessierungsablaufes knapp erläutert wurden, werden die Unterschiede bei der Doppeldifferenzbildung benachbarter und identischer Wiederholspuren herausgearbeitet. Danach wird am Beispiel gezeigt, wie mithilfe von ICESat-Daten (Ice, Cloud and Land Elevation Satellite) eine Basislinienverbesserung zur genaueren Höhenbestimmung durchgeführt werden kann. Die ursprünglich separat abgeleiteten Höhenmodelle werden dann zu einer gemeinsamen Lösung kombiniert, welche abschließend hinsichtlich ihrer Genauigkeit besprochen und anderen Modellen vergleichend gegenübergestellt wird. Die Ableitung von Fließgeschwindigkeiten mit dem Hintergrund einer späteren Berechnung von Massenflüssen ist Gegenstand des fünften Kapitels, wobei drei unterschiedliche Methoden genutzt werden. Im ersten Fall wird das für RADAR-Bilder typische, hochfrequente Rauschen zur Bestimmung von Verschiebungen in ALOS-Daten (Advanced Land Observing Satellite) genutzt. Mit dieser Methode können durchgehende Fließgeschwindigkeitsfelder vom aufliegenden Bereich über die Aufsetzzone bis auf das Schelfeis ermittelt werden. DesWeiteren werden aus ERS-Daten (European Remote Sensing Satellite), die über einen Zeitraum von reichlich 13 Jahren vorliegen, Verschiebungen durch die Verfolgung von unveränderten, aber sich bewegenden Eisstrukturen bestimmt. Bei der als Drittes angewendeten, interferometrischen Methode werden aufsteigende und absteigende Satellitenspuren kombiniert, um die Fließinformationen zu rekonstruieren. In den jeweiligen Sektionen wird neben der Vorstellung der Ergebnisse auch deren Genauigkeit diskutiert. Das letzte große, sechste Kapitel untergliedert sich in zwei Teile. Im ersten dieser beiden Abschnitte wird gezeigt, wie InSAR und DInSAR zur Lagekartierung der Aufsetzzone eingesetzt werden können. Dabei werden die auf diese Weise ermittelten Ergebnisse dargestellt und diskutiert. Im zweiten, umfangreicheren Teil werden die zuvor gewonnenen Höhen- und Geschwindigkeitsinformationen genutzt, um deren Einfluss aus den InSAR-Messungen zu eliminieren, wodurch vertikale Höhenunterschiede mittels InSAR bestimmt werden können. Dies ist besonders für den Bereich der Aufsetzzone und des Schelfeises von Interesse, da diese Areale teilweise oder vollständig von Ozeangezeiten beeinflusst werden. Nach einer Luftdruckkorrektion werden den ermittelten Höhenunterschieden (entlang selektierter Profile) die Prädiktionen zwölf verfügbarer Ozeangezeitenmodelle gegenübergestellt. Die RMS-Werte dieser Differenzen werden abschließend genutzt, um die Qualität der Ozeangezeitenmodelle für die Region des Arbeitsgebietes einzustufen. Zum Abschluss werden in einer Zusammenfassung noch einmal die wichtigsten Ergebnisse aller Kapitel resümiert und bewertet.<br>The development of new satellite sensors within the last 20 years along with changes towards more sophisticated processing strategies has not only given a new impetus to remote sensing data in view of polar research but also changed how a variety of glaciological problems are being addressed today. Particularly RADAR (radio detection and ranging) sensors are well-suited for the observation of glaciated areas and have already helped to retrieve a vast amount of climate sensitive parameters from the area of Antarctica. After an introductive overview at the beginning, the second chapter continues with the description of how RADAR measurements can be used to generate remote sensing images. The principle of synthetic aperture RADAR (SAR) which allows a better focusing of the RADAR measurements and therewith a rigorous increase of the spatial resolution of the images is outlined generally before more precise descriptions explain how interferometric SAR (InSAR) analyses can be used for the determination of surface topography heights and area-wide flow velocities. Two other techniques, namely matching methods for the determination of shifts between two images as well as the laser satellite altimetry are explained at the end of this chapter which closes the theoretical basics. The next section introduces the area of interest along with data sets which were used for validation purposes. After a careful exposure of the geographical situation, single objects such as ice streams and ice shelves are described in more detail. The following part, the data set introduction, has besides the description of other measurements its focus on topography and ocean tide models which are available for the area of investigation. Chapter four deals with the estimation of surface topography heights from differential InSAR (DInSAR) analyses. Therein the major differences for the usage of similar repeat tracks in contrast to neighboring, overlapping tracks will be shown and thoroughly discussed. The example of one track will be used to demonstrate how the required baseline estimation can be achieved if ICESat (Ice, Cloud and Land Elevation Satellite) profiles are used as tie points. Afterwards, all separately derived height models will be combined to obtain one final solution followed by an error analysis. A comparison to other available elevation models visualizes the spatial resolution of the derived model. The utilization of three different methods for the estimation of surface flow velocities (with the background of possible mass flux determinations) is the topic of the fifth chapter. The first case describes the usage of the high frequent noise contained in RADAR images for the tracking of horizontal surface displacements. Based on ALOS (Advanced Land Observing Satellite) data a flow velocity field which extends from the interior of the ice sheet across the grounding zone up to the ice shelf will be presented. Secondly, geocoded ERS (European Remote Sensing Satellite) images covering a time span of more than 13 years are used to track the motions of well-structured flat areas (ice shelf and glacier tongue). In the third approach used descending and ascending satellite passes will be combined in conjunction with a surface parallel flow assumption to interferometrically derive flow velocities in grounded areas. In each section respective errors will be discussed in order to evaluate the accuracy of the performed measurements. The last bigger chapter, number six, is divided into two sections. In the first one the adoption of SAR and InSAR with respect to the mapping of the grounding line location will be demonstrated. Results of the entire working area will be presented and compared to other data. The second section deploys the results of topography heights and flow velocities to remove both effects from the InSAR measurements which then allows to also measure height changes. This is of particular interest for the floating areas of ice shelf which are fully affected by ocean tides as well as for the grounding zone locations which partially experience deformations due to these height changes. After the correction for air pressure, changes between the image acquisitions, height changes along selected profiles are compared to twelve different ocean tide models. The RMS values of the differences are then used to evaluate the quality of these models for the working area. The most important results and conclusions are summarized in the last chapter.
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