subject:(Radar Modeling)

University of Oklahoma

1. Lucking, David. Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking.

Degree: PhD, 2019, University of Oklahoma

URL: http://hdl.handle.net/11244/320358

► A sensor's performance is constrained by the amount of resources at its disposal and the utilization of those resources. A radar system, for example, has… (more)

▼ A sensor's performance is constrained by the amount of resources at its disposal and the utilization of those resources. A radar system, for example, has a limited amount of transmit power-aperture per unit time to track a multitude of targets. A typical approach when tracking multiple dynamic targets is to time interleave the update intervals until all the radar tasks are performed. The advent of more agile sensors, such as digital-at-every-element apertures, opens the possibility for dynamic sensor resource allocation strategies to achieve better tracking performance in target-dense, resource-constrained scenarios. With proper research into aperture allocation, such as the analysis provided in this dissertation, an all-digital radar can intelligently exploit the degrees of freedom offered by all-digital radars to increase tracking performance. In this dissertation, we investigate adaptive aperture allocation for tracking a large number of targets. The strategies are first introduced with a parallel, linear channel model, then increased in realism with a non-linear measurement model, and finally applied to a full tracking system. We derive various strategies for allocating power and aperture, and compare their performance based on tracking related metrics. Finally, we investigate the relationship between the aperture allocation strategies and the target locations for multiple scenarios designed to represent the environment for a radar tracking system. This research provides groundbreaking strategies for optimal radar aperture allocation using the digital-at-every-element architectures to reduce the overall system uncertainty and decrease the uncertainty on a per-target basis. Integrating aperture allocation with the management of other degrees of freedom will increase multi-target tracking performance well beyond the current state of the art. Advisors/Committee Members: Goodman, Nathan (advisor), Fulton, Caleb (committee member), Yeary, Mark (committee member), Antonio, John (committee member), Sigmarsson, Hjalti (committee member).

Subjects/Keywords: Digital Arrays; Multi-Target Tracking; Radar Modeling; Radar Resource Management; Radar Signal Processing

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APA (6^th Edition):

Lucking, D. (2019). Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/320358

Chicago Manual of Style (16^th Edition):

Lucking, David. “Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking.” 2019. Doctoral Dissertation, University of Oklahoma. Accessed January 18, 2021. http://hdl.handle.net/11244/320358.

MLA Handbook (7^th Edition):

Lucking, David. “Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking.” 2019. Web. 18 Jan 2021.

Vancouver:

Lucking D. Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking. [Internet] [Doctoral dissertation]. University of Oklahoma; 2019. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/11244/320358.

Council of Science Editors:

Lucking D. Digital-At-Every-Element Radar Resource Allocation for Multi-Target Tracking. [Doctoral Dissertation]. University of Oklahoma; 2019. Available from: http://hdl.handle.net/11244/320358

2. Khawar, Awais. Spectrum Sharing between Radar and Communication Systems.

Degree: PhD, Electrical Engineering, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/54548

► Radio frequency spectrum is a scarce natural resource that is utilized for many services including surveillance, navigation, communication, and broadcasting. Recent years have seen tremendous… (more)

▼ Radio frequency spectrum is a scarce natural resource that is utilized for many services including surveillance, navigation, communication, and broadcasting. Recent years have seen tremendous growth in use of spectrum especially by commercial cellular operators. As a result, cellular operators are experiencing a shortage of radio spectrum to meet bandwidth demands of users. Spectrum sharing is a promising approach to solve the problem of spectrum congestion as it allows cellular operators access to more spectrum in order to satisfy the ever growing bandwidth demands of commercial users. The US spectrum regulatory bodies are working on an initiative to share 150 MHz of spectrum, held by federal agencies, in the 3.5 GHz band with commercial wireless operators. This band is primarily used by radar systems that are critical to national defense. Field tests have shown that spectrum sharing between radars and communication systems require large separation distance in order to protect them from harmful interference. Thus, novel methods are required to ensure spectrum sharing between the two systems without the need of large protection distances. In order to efficiently share spectrum between radars and communication systems at the same time and in the same geographical area, a novel method is proposed that transforms radar signal in such a way that it does not interfere with communication systems. This is accomplished by projecting the radar signal onto null space of the wireless channel between radar and communication system. In order to understand the effects of the proposed sharing mechanism – in urban, sub-urban, and littoral areas – new channel models, specifically, two- and three-dimensional channel models are designed that capture azimuth and elevation angles of communication systems and helps in placing accurate nulls. In addition, interference coming from communication systems into radar receivers is analyzed and radar performance is accessed. Using this information, resource allocation schemes are designed for communication systems that take advantage of the carrier aggregation feature of the LTE-Advanced systems. This further helps in dynamic sharing of spectrum between radars and communication systems. The proposed signal projection approach not only meets radar objectives but also meets spectrum sharing objectives. However, there is a trade-off as signal projection results in some performance degradation for radars. Performance metrics such as probability of target detection, Cramer Rao bound and maximum likelihood estimate of target's angle of arrival, and beampattern of radar are studied for performance degradation. The results show minimal degradation in radar performance and reduction in exclusion zones, thus, showing the efficacy of the proposed approach. Advisors/Committee Members: Clancy, Thomas Charles (committeechair), Shukla, Sandeep K. (committee member), McGwier, Robert W. (committee member), Roan, Michael J. (committee member), Reed, Jeffrey H. (committee member).

Subjects/Keywords: spectrum sharing; MIMO radar; null steering; radar waveform design; channel modeling

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APA (6^th Edition):

Khawar, A. (2015). Spectrum Sharing between Radar and Communication Systems. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/54548

Chicago Manual of Style (16^th Edition):

Khawar, Awais. “Spectrum Sharing between Radar and Communication Systems.” 2015. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/54548.

MLA Handbook (7^th Edition):

Khawar, Awais. “Spectrum Sharing between Radar and Communication Systems.” 2015. Web. 18 Jan 2021.

Vancouver:

Khawar A. Spectrum Sharing between Radar and Communication Systems. [Internet] [Doctoral dissertation]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/54548.

Council of Science Editors:

Khawar A. Spectrum Sharing between Radar and Communication Systems. [Doctoral Dissertation]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/54548

University of Oklahoma

3. Putnam, Bryan. THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS.

Degree: PhD, 2016, University of Oklahoma

URL: http://hdl.handle.net/11244/34807

► Accurately representing the microphysical state of precipitation using bulk microphysics schemes, including the hydrometeor particle size distributions (PSDs), is vital to improving convective-scale forecasts. In… (more)

▼ Accurately representing the microphysical state of precipitation using bulk microphysics schemes, including the hydrometeor particle size distributions (PSDs), is vital to improving convective-scale forecasts. In this dissertation, results will be presented from three related projects that combine the use of dual-polarimetric (dual-pol) radar observations and ensemble forecast methods to evaluate and improve the forecast model microphysical state. The dual-pol variables provide additional information on hydrometeor types and their PSDs compared to reflectivity (Z) alone. In the first project, simulated dual-pol variables from several members of the 2013 CAPS Storm Scale Ensemble Forecasts (SSEF) that use different microphysics schemes are compared to dual-pol observations. The microphysics schemes vary significantly and include single-moment (SM) WSM6, partially double-moment (DM) Thompson and WDM6, and fully DM Milbrandt and Yau and Morrison. Both a mesoscale convective system (MCS) and supercell case are considered due to the different patterns in the dual-pol variable fields unique to each case. Results show that the forecasts using the Morrison scheme and the Milbrandt and Yau scheme have patterns of high differential reflectivity (ZDR) indicative of size sorting that match similar patterns in the observations. The dual-pol variables also help highlight biases in the forecasts including the under-prediction of liquid water content and the over-prediction of particular hydrometeor types such as graupel. In the second project, probabilistic forecasts of simulated dual-pol variables are performed. Ensemble forecasts of a mesoscale convective system (MCS) from 9 May 2007 are initialized from ensemble Kalman filter (EnKF) analyses using both SM and DM microphysics schemes. Qualitative analysis of simulated ZDR shows that the DM experiment better represents the PSDs of the convective and stratiform precipitation regions, while the KDP fields show that the SM experiment over-forecasts liquid water content in the convective areas. Quantitative ensemble forecast verification methods using dual-pol variables are considered for the first time and reveal the challenges associated with evaluating dual-pol fields that have very fine-scale details. Finally, in the third project, dual-pol variables are assimilated using the EnKF and a DM microphysics scheme for two supercell cases: 10 May 2010 and 20 May 2013. For each case, both ZDR and KDP are assimilated in separate experiments in addition to Z and radial velocity (Vr) and compared to a control experiment that assimilates only Z and Vr. The results show that the simulated dual-pol fields in the analyses of the dual-pol experiments better represent documented polarimetric signatures, such as the ZDR arc, compared to the control experiment. Additionally, comparisons of model microphysical variables and mean mass diameter between the dual-pol and control experiments show that the dual-pol experiments have an improved microphysical state. For example, the mean mass… Advisors/Committee Members: Xue, Ming (advisor), Zhang, Guifu (advisor), Jung, Youngsun (committee member), Bluestein, Howard (committee member), Lakshmivarahan, S (committee member).

Subjects/Keywords: data assimilation; polarimetric radar; convective-scale modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Putnam, B. (2016). THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/34807

Chicago Manual of Style (16^th Edition):

Putnam, Bryan. “THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS.” 2016. Doctoral Dissertation, University of Oklahoma. Accessed January 18, 2021. http://hdl.handle.net/11244/34807.

MLA Handbook (7^th Edition):

Putnam, Bryan. “THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS.” 2016. Web. 18 Jan 2021.

Vancouver:

Putnam B. THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS. [Internet] [Doctoral dissertation]. University of Oklahoma; 2016. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/11244/34807.

Council of Science Editors:

Putnam B. THE PREDICTION AND ASSIMILATION OF POLARIMETRIC RADAR DATA USING ENSEMBLE-BASED METHODS. [Doctoral Dissertation]. University of Oklahoma; 2016. Available from: http://hdl.handle.net/11244/34807

4. Rocha Filho, Kleber Lopes da. Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico.

Degree: Mestrado, Meteorologia, 2010, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/14/14133/tde-21062013-124917/ ;

►

A Bacia do Alto Tiete abriga cerca de 50% dos habitantes do Estado de São Paulo e é afetada freqüentemente por eventos de inundações. Uma… (more)

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A Bacia do Alto Tiete abriga cerca de 50% dos habitantes do Estado de São Paulo e é afetada freqüentemente por eventos de inundações. Uma das principais fontes de problemas é a alta impermeabilização devida à ocupação da superfície nas últimas décadas. Um dos seus tributários secundários, a bacia do Rio Pirajuçara se insere neste contexto e sofre com problemas da mesma natureza. A modelagem hidrológica permite uma análise do escoamento superficial nestes ambientes e é útil na previsão de vazões por meio de redes telemétricas e sensoriamento remoto. Entretanto, redes telemétricas apresentam problemas de representatividade espacial e exposição, radares meteorológicos, apesar da maior resolução espaço-temporal das estimativas de precipitação, possuem várias fontes de erros e incertezas. A principal delas se refere à relação ZR. Deste modo, a integração dessas medições e estimativas pode minimizar erros de ambas. O objetivo deste estudo é analisar aspectos hidrológicos da Bacia do Rio Pirajuçara por meio do modelo TOPMODEL com medições de vazão e precipitação disponíveis para 18 eventos monitorados entre outubro de 2008 a outubro de 2009. O modelo TOPMODEL foi calibrado com dez eventos e verificado com os demais. A calibração foi realizada com os dados da telemetria da Bacia do Alto Tietê, radar meteorológico de São Paulo e a combinação de ambos por meio da análise objetiva estatística. Os resultados da calibração indicam que o melhor desempenho foi obtido com radar meteorológico, com número de NASH de 0,51, menor erro quadrático médio e menor viés médio absoluto. A verificação também indicou o mesmo resultado com número de NASH de 0,69. As simulações indicam que apesar da utilização da precipitação média, o modelo TOPMODEL simulou adequadamente cerca de 75% das vazões de alerta. O trabalho evidencia as limitações da telemetria e seus impactos na integração com os dados do radar.

The Alto Tiete watershed is home for about 50% of the inhabitants of São Paulo State and is affected by recurrent flashfloods. One major source of difficulties is the high rate of soil impermeabilization caused by dense surface occupation in the last decades. One of its secondary tributaries, the Pirajussara watershed suffers with similar problems. Hydrological modeling allows the analysis of runoff and other variables in these basins. It also useful for streamflow forecast based on telemetric networks and remote sensing measurements. However, surface networks lack spatial representativity and exposure is a also a issue, weather radars, in spite of their much higher spatial and temporal resolution rainfall estimation, are affect by several sources of errors and uncertainties; the most significant one being the ZR relationship. Thus, the integration of these measurements and estimates can minimize errors of both. The goal of the present work is to analyze the surface hydrology of the Pirajussara watershed based on the TOPMODEL, streamflow and rainfall measurements available for eighteen events between October 2008 and October 2009. The…

Advisors/Committee Members: Pereira Filho, Augusto Jose.

Subjects/Keywords: Hydrologic Modeling; Modelagem Hidrológica; Radar meteorológico; Raingauge Network.; Redes de Superfície; TOPMODEL; TOPMODEL; Weather Radar

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rocha Filho, K. L. d. (2010). Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/14/14133/tde-21062013-124917/ ;

Chicago Manual of Style (16^th Edition):

Rocha Filho, Kleber Lopes da. “Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico.” 2010. Masters Thesis, University of São Paulo. Accessed January 18, 2021. http://www.teses.usp.br/teses/disponiveis/14/14133/tde-21062013-124917/ ;.

MLA Handbook (7^th Edition):

Rocha Filho, Kleber Lopes da. “Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico.” 2010. Web. 18 Jan 2021.

Vancouver:

Rocha Filho KLd. Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico. [Internet] [Masters thesis]. University of São Paulo; 2010. [cited 2021 Jan 18]. Available from: http://www.teses.usp.br/teses/disponiveis/14/14133/tde-21062013-124917/ ;.

Council of Science Editors:

Rocha Filho KLd. Modelagem Hidrológica da Bacia do Rio Pirajuçara com TOPMODEL, Telemetria e Radar Meteorológico. [Masters Thesis]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/14/14133/tde-21062013-124917/ ;

INP Toulouse

5. Halimi, Abderrahim. From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler.

Degree: Docteur es, Signal, image, acoustique et optimisation, 2013, INP Toulouse

URL: http://www.theses.fr/2013INPT0080

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Depuis plus de vingt ans, les altimètres classiques comme Topex, Poseidon-2 ou Poséidon-3, ont fourni des formes d'onde qui sont utilisées pour estimer de nombreux… (more)

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Depuis plus de vingt ans, les altimètres classiques comme Topex, Poseidon-2 ou Poséidon-3, ont fourni des formes d'onde qui sont utilisées pour estimer de nombreux paramètres tels que la distance entre le satellite et la scène observée, la hauteur des vagues et la vitesse du vent. L'amélioration de la qualité des paramètres altimétriques a nécessité le développement de plusieurs modèles d'échos et d'algorithmes d'estimation paramétrique. Par ailleurs, un grand effort est récemment dédié au traitement des échos côtiers afin d'analyser les mesures altimétriques le plus près possible des côtes. Cette thèse s'intéresse à la résolution de ces deux problèmes, à savoir, le traitement des formes d'onde côtières et l'amélioration de la qualité des paramètres océaniques estimés. La première partie de l'étude traite le problème des formes d'onde côtières en proposant un nouveau modèle altimétrique tenant compte de la présence éventuelle d'un pic sur l'écho altimétrique. Dans la seconde partie de notre travail, nous nous sommes intéressés à l'étude de l'altimétrie SAR/Doppler. Cette nouvelle technologie vise à réduire le bruit de mesure et à augmenter la résolution le long de la trace par rapport à l'altimétrie conventionnelle. Deux modèles altimétriques ont été développés afin d'estimer les paramètres associés aux échos SAR/Doppler. Ces modèles montrent une nette amélioration de la qualité des paramètres estimés par rapport à l'altimétrie conventionnelle.

For more than twenty years, conventional altimeters like Topex, Poseidon-2 or Poseidon-3, have been delivering waveforms that are used to estimate many parameters such as the range between the satellite and the observed scene, the wave height and the wind speed. Several waveform models and estimation processing have been developed for the oceanic data in order to improve the quality of the estimated altimetric parameters. Moreover, a great effort has been devoted to process coastal echoes in order to move the altimetric measurements closer to the coast. In this thesis, we are interested in resolving these two problems, i.e., processing coastal waveforms and improving the quality of the estimated oceanic parameters. The first part of the study considers the problem of coastal waveforms and proposes a new altimetric model taking into account the possible presence of peaks affecting altimetric echoes. In a second part of our work, we have been interested in the delay/Doppler altimetry. This new technology aims at reducing the measurement noise and increasing the alongtrack resolution when compared to conventional altimetry. Two altimetric models have been developed in order to estimate the resulting delay/Doppler echoes. These models allow a clear improvement in parameter estimation when compared to conventional altimetry.

Advisors/Committee Members: Mailhes, Corinne (thesis director), Tourneret, Jean-Yves (thesis director).

Subjects/Keywords: Altimétrie; Altimétrie SAR/Doppler; Estimation; Modélisation; Radar; Altimetry; Delay/Doppler altimetry; Estimation; Modeling; Radar

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Halimi, A. (2013). From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2013INPT0080

Chicago Manual of Style (16^th Edition):

Halimi, Abderrahim. “From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler.” 2013. Doctoral Dissertation, INP Toulouse. Accessed January 18, 2021. http://www.theses.fr/2013INPT0080.

MLA Handbook (7^th Edition):

Halimi, Abderrahim. “From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler.” 2013. Web. 18 Jan 2021.

Vancouver:

Halimi A. From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler. [Internet] [Doctoral dissertation]. INP Toulouse; 2013. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2013INPT0080.

Council of Science Editors:

Halimi A. From conventional to delay/Doppler altimetry : De l'altimétrie conventionnelle à l'altimétrie SAR/Doppler. [Doctoral Dissertation]. INP Toulouse; 2013. Available from: http://www.theses.fr/2013INPT0080

6. Monvoisin, Jean-Pascal. Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon.

Degree: Docteur es, Electromagnétisme et Systèmes Haute Fréquence, 2018, Université Toulouse III – Paul Sabatier

URL: http://www.theses.fr/2018TOU30177

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Ce travail se situe dans le cadre général de la modélisation cohérente de l'interaction des ondes électromagnétiques avec les surfaces végétalisées. Notre objectif a été… (more)

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Ce travail se situe dans le cadre général de la modélisation cohérente de l'interaction des ondes électromagnétiques avec les surfaces végétalisées. Notre objectif a été de développer une approche de la simulation électromagnétique avec prise en compte de la topographie et des hétérogénéités de la végétation. La validation des résultats obtenus a été réalisée en s'appuyant sur de nombreuses mesures in-situ. Nous avons ensuite mis en œuvre cet outil de modélisation sur les deux problématiques suivantes. D'une part, nous nous sommes intéressés à l'étude des forêts tropicales dans un contexte d'inversion de propriétés bio-géophysiques (biomasse, humidité). D'autre part, nous avons introduit la prise en compte de la présence d'hydrocarbures essentiellement sur la végétation basse dans un contexte de caractérisation et d'exploration. Ce travail s'inscrit dans un programme de recherche et d'innovation en télédétection mené conjointement par l'ONERA et Total. La première étape a consisté à une écriture du code cohérent de simulation électromagnétique avec prise en compte du relief et de l'hétérogénéité de la végétation. Pour cela, le sol a été discrétisé en triangles et le volume en pentaèdres reposant sur le sol Après avoir validé notre code sur des exemples théoriques, nous avons pu étudier les effets du relief sur la rétrodiffusion radar. Pour les forêts tropicales, un modèle de description de la végétation a été mis en place à partir de mesures in-situ et d'observations directes. Ce modèle sert de données d'entrée pour notre code de simulation électromagnétique et nous permet ainsi de confronter nos simulations aux mesures aéroportées et de proximités acquises par l'ONERA sur deux sites en Afrique Des études de sensibilité aux paramètres d'entrée du code de simulation électromagnétique et du code de croissance sont présentées. En parallèle, des modèles de substitution au code numérique ont été mis en place pour effectuer l'inversion. Ces modèles sont moins coûteux à évaluer tout en restant précis. Une application à l'inversion est présentée : pour un jeu d'image radar, il s'agit de retrouver les caractéristiques bio-géophysiques de la forêt observée (humidités, biomasse...). Pour terminer, nous avons étudié les effets des hydrocarbures sur la rétrodiffusion radar pour une végétation basse. [...]

This work is in the general frame of coherent modelling of interaction between electromagnetic waves and surfaces with vegetation. Our objective is to develop an approach of the electromagnetic simulation taking into account topography and vegetation heterogeneities. Simulation results have been validated using numerous in-situ measurements. The corresponding code is then used for two issues. First one is the study of tropical forests to retrieve bio-geophysical properties (biomass, moisture). Second one is the consideration of hydrocarbons with short vegetation in a context of hydrocarbons characterization and exploration. This work is part of a program of research and innovation in remote sensing conducted jointly by ONERA…

Advisors/Committee Members: Borderies, Pierre (thesis director).

Subjects/Keywords: SAR; Modélisation radar; Rétrodiffusion; Forêt; Hydrocarbures; Radar à antenne synthétique; SAR; Radar modeling; Backscattering; Forest diffraction; Hydrocarbons

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Monvoisin, J. (2018). Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon. (Doctoral Dissertation). Université Toulouse III – Paul Sabatier. Retrieved from http://www.theses.fr/2018TOU30177

Chicago Manual of Style (16^th Edition):

Monvoisin, Jean-Pascal. “Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon.” 2018. Doctoral Dissertation, Université Toulouse III – Paul Sabatier. Accessed January 18, 2021. http://www.theses.fr/2018TOU30177.

MLA Handbook (7^th Edition):

Monvoisin, Jean-Pascal. “Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon.” 2018. Web. 18 Jan 2021.

Vancouver:

Monvoisin J. Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon. [Internet] [Doctoral dissertation]. Université Toulouse III – Paul Sabatier; 2018. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2018TOU30177.

Council of Science Editors:

Monvoisin J. Modélisation de la diffraction électromagnétique des surfaces végétalisées avec prise en compte de la topographie : application à l'étude des forêts tropicales et à la présence d'hydrocarbure sur le sol : Electromagnetic diffraction of vegetable surfaces with topography : application to tropical forests and to the presence of hydrocarbon. [Doctoral Dissertation]. Université Toulouse III – Paul Sabatier; 2018. Available from: http://www.theses.fr/2018TOU30177

Arizona State University

7. Hjelmstad, Annika. Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ.

Degree: Civil, Environmental and Sustainable Engineering, 2020, Arizona State University

URL: http://repository.asu.edu/items/57215

► The Phoenix Metropolitan region is subject to intense summer monsoon thunderstorms that cause highly localized flooding. Due to the challenges in predicting these meteorological phenomena… (more)

Subjects/Keywords: Civil engineering; Hydrologic sciences; hydraulic modeling; hydrologic modeling; hydrometeorology; radar rainfall; stochastic hydrology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hjelmstad, A. (2020). Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ. (Masters Thesis). Arizona State University. Retrieved from http://repository.asu.edu/items/57215

Chicago Manual of Style (16^th Edition):

Hjelmstad, Annika. “Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ.” 2020. Masters Thesis, Arizona State University. Accessed January 18, 2021. http://repository.asu.edu/items/57215.

MLA Handbook (7^th Edition):

Hjelmstad, Annika. “Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ.” 2020. Web. 18 Jan 2021.

Vancouver:

Hjelmstad A. Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ. [Internet] [Masters thesis]. Arizona State University; 2020. [cited 2021 Jan 18]. Available from: http://repository.asu.edu/items/57215.

Council of Science Editors:

Hjelmstad A. Propagation of Radar Rainfall Uncertainties into Urban Flood Predictions: An Application in Phoenix, AZ. [Masters Thesis]. Arizona State University; 2020. Available from: http://repository.asu.edu/items/57215

University of Colorado

8. Kalina, Evan Anthony. Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics.

Degree: PhD, Atmospheric & Oceanic Sciences, 2015, University of Colorado

URL: https://scholar.colorado.edu/atoc_gradetds/50

► Dual-polarization radar, disdrometer, lightning, and model data are analyzed to determine 1) the usefulness and accuracy of disdrometer and attenuation-corrected X-band mobile radar data… (more)

▼ Dual-polarization radar, disdrometer, lightning, and model data are analyzed to determine 1) the usefulness and accuracy of disdrometer and attenuation-corrected X-band mobile radar data from severe thunderstorms, 2) the effect of cloud condensation nuclei (CCN) concentration on idealized supercell thunderstorms, and 3) the synoptic weather, dual-polarization radar, and lightning characteristics of Colorado plowable hailstorms. The results in Chapter 2 demonstrate that the best agreement (1 dB in reflectivity Z and 0.2 dB in differential reflectivity Z_DR) between the disdrometer and X-band radar data was obtained when the radar signal quality index (SQI) was at least 0.8 and large hail was not present. Disagreement in Z (Z_DR) increased to 6 dB (1.6 dB) and 13 dB (0.6 dB) in large hail and SQI < 0.8, respectively. Since better agreement was obtained under these conditions when the disdrometer measurements were compared to S-band radar data, the X-band attenuation-correction scheme was likely responsible for the disagreement. In Chapter 3, results from idealized supercell thunderstorm simulations in which the CCN concentration was varied from 100-10 000 cm^-3 for several different environmental soundings are presented. Changes in the microphysical process rates saturated at CCN = 3000 cm^-3. In heavily polluted conditions (CCN = 10 000 cm^-3), supercell thunderstorms formed up to 30% larger rain and 3% larger hail particles, produced up to 25 mm more precipitation near the updraft, and tracked more poleward. The area and size of the cold pool were also sensitive to the CCN concentration, especially when the low-level relative humidity was fairly dry (~60%). Chapter 4 analyzes the synoptic weather, radar, and lightning characteristics from four severe thunderstorms that produced "plowable" hail accumulations of 15-60 cm along the Colorado Front Range. Westerly flow at 500 hPa at slow speeds (5-15 m s^-1), combined with moist upslope low-level flow, accompanied each hailstorm. The accumulated hail mass derived from the radar data pinpointed the times and locations of deep hail, with estimated hail depths of greater than 5 cm (less than 1.5 cm) in areas with plowable (non-plowable) hail. An increase in lightning flash rate also preceded deep hail accumulations. Advisors/Committee Members: Katja Friedrich, George H. Bryan, John J. Cassano, Jeffrey P. Thayer, Owen B. Toon.

Subjects/Keywords: aerosols; hail; microphysics; modeling; radar; thunderstorms; Atmospheric Sciences; Meteorology

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APA (6^th Edition):

Kalina, E. A. (2015). Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/atoc_gradetds/50

Chicago Manual of Style (16^th Edition):

Kalina, Evan Anthony. “Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics.” 2015. Doctoral Dissertation, University of Colorado. Accessed January 18, 2021. https://scholar.colorado.edu/atoc_gradetds/50.

MLA Handbook (7^th Edition):

Kalina, Evan Anthony. “Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics.” 2015. Web. 18 Jan 2021.

Vancouver:

Kalina EA. Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2021 Jan 18]. Available from: https://scholar.colorado.edu/atoc_gradetds/50.

Council of Science Editors:

Kalina EA. Using Disdrometer, Radar, Lightning, and Model Data to Investigate Severe Thunderstorm Microphysics. [Doctoral Dissertation]. University of Colorado; 2015. Available from: https://scholar.colorado.edu/atoc_gradetds/50

Delft University of Technology

9. Ku, Ou (author). Mathematical Model Selection for InSAR Deformation Times Series.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:2d3b25e0-741d-4ef4-a10e-b63c7ecb70d6

► Satellite radar interferometry (InSAR) techniques can monitor the ground deformation with millimeter precision. With Time-series InSAR (TInSAR) methodology, the ground deformation time series can be… (more)

▼ Satellite radar interferometry (InSAR) techniques can monitor the ground deformation with millimeter precision. With Time-series InSAR (TInSAR) methodology, the ground deformation time series can be derived from InSAR observations. One of the important ways to analyze the InSAR deformation time series is to parameterize the InSAR deformation time series with deformation models. The previous ways of modelling InSAR deformation time series are usually point-wise, i.e. they focus on the deformation models of single InSAR measurement points. The deformation model of each point is either assumed to be a linear function of time, or is selected from the predefined alternative models. The point-wise modeling methodologies can well interpret the deformation behavior of each point, but is limited on modeling the spatial deformation patterns. In this study, we design and implement methodologies to model the spatio-temporal deformation patterns, based on given spatial smoothness information of the deformation. We introduce a work flow to digest the spatial smoothness information from external sources, and use the information to improve the functional and stochastic model. We also propose a model selection methodology based on hypothesis testing to select the the most probable spatio-temporal deformation model from given potential models. The spatio-temporal deformation modeling methodology is applied to the simulated data, as well as the real InSAR measurements. We apply the spatio-temporal deformation methodology to study the deformation in a hydrocarbon production field in California, and successfully detect the instantaneous uplifting and subsiding events. Based on the simulation and real case study, we conclude that given proper contextual information, spatio-temporal deformation modeling is able to derive the deformation model in both temporal and spatial domain, and has a good performance on parameterizing the non-linear deformation behavior in the temporal domain. Advisors/Committee Members: Chang, Ling (mentor), Hanssen, Ramon (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Satellite Radar Interferometry; Spatio-temporal Deformation Modeling; Hydrocarbon Production

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APA (6^th Edition):

Ku, O. (. (2017). Mathematical Model Selection for InSAR Deformation Times Series. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:2d3b25e0-741d-4ef4-a10e-b63c7ecb70d6

Chicago Manual of Style (16^th Edition):

Ku, Ou (author). “Mathematical Model Selection for InSAR Deformation Times Series.” 2017. Masters Thesis, Delft University of Technology. Accessed January 18, 2021. http://resolver.tudelft.nl/uuid:2d3b25e0-741d-4ef4-a10e-b63c7ecb70d6.

MLA Handbook (7^th Edition):

Ku, Ou (author). “Mathematical Model Selection for InSAR Deformation Times Series.” 2017. Web. 18 Jan 2021.

Vancouver:

Ku O(. Mathematical Model Selection for InSAR Deformation Times Series. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 18]. Available from: http://resolver.tudelft.nl/uuid:2d3b25e0-741d-4ef4-a10e-b63c7ecb70d6.

Council of Science Editors:

Ku O(. Mathematical Model Selection for InSAR Deformation Times Series. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:2d3b25e0-741d-4ef4-a10e-b63c7ecb70d6

Virginia Tech

10. Eltrass, Ahmed Said Hassan Ahmed. The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals.

Degree: PhD, Electrical Engineering, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/51804

► The mid-latitude ionosphere is more complicated than previously thought, as it includes many different scales of wave-like structures. Recent studies reveal that the mid-latitude ionospheric… (more)

▼ The mid-latitude ionosphere is more complicated than previously thought, as it includes many different scales of wave-like structures. Recent studies reveal that the mid-latitude ionospheric irregularities are less understood due to lack of models and observations that can explain the characteristics of the observed wave structures. Since temperature and density gradients are a persistent feature in the mid-latitude ionosphere near the plasmapause, the drift mode growth rate at short wavelengths may explain the mid-latitude decameter-scale ionospheric irregularities observed by the Super Dual Auroral Radar Network (SuperDARN). In the context of this dissertation, we focus on investigating the plasma waves responsible for the mid-latitude ionospheric irregularities and studying their influence on Global Positioning System (GPS) scintillations. First, the physical mechanism of the Temperature Gradient Instability (TGI), which is a strong candidate for producing mid-latitude irregularities, is proposed. The electro- static dispersion relation for TGI is extended into the kinetic regime appropriate for High- Frequency (HF) radars by including Landau damping, finite gyro-radius effects, and tem- perature anisotropy. The kinetic dispersion relation of the Gradient Drift Instability (GDI) including finite ion gyro-radius effects is also solved to consider decameter-scale waves gen- eration. The TGI and GDI calculations are obtained over a broad set of parameter regimes to underscore limitations in fluid theory for short wavelengths and to provide perspective on the experimental observations. Joint measurements by the Millstone Hill Incoherent Scatter Radar (ISR) and the Su- perDARN HF radar located at Wallops Island, Virginia have identified the presence of decameter-scale electron density irregularities that have been proposed to be responsible for low-velocity Sub-Auroral Ionospheric Scatter (SAIS) observed by SuperDARN radars. In order to investigate the mechanism responsible for the growth of these irregularities, a time series for the growth rate of both TGI and GDI is developed. The time series is computed for both perpendicular and meridional density and temperature gradients. The growth rate comparison shows that the TGI is the most likely generation mechanism for the observed quiet-time irregularities and the GDI is expected to play a relatively minor role in irregular- ity generation. This is the first experimental confirmation that mid-latitude decameter-scale ionospheric irregularities are produced by the TGI or by turbulent cascade from primary irregularity structures produced from this instability. The quiet- and disturbed-times plasma wave irregularities are compared by investigating co-located experimental observations by the Blackstone SuperDARN radar and the Millstone Hill ISR under various sets of geomagnetic conditions. The radar observations in conjunction with growth rate calculations suggest that the TGI in association with the GDI or a cascade product from them may cause the observations of… Advisors/Committee Members: Scales, Wayne A. (committeechair), Meehan, Kathleen (committee member), Riad, Sedki Mohamed (committee member), Winfrey, Leigh (committee member), Elkamchouchi, Hassan M. (committee member), Ruohoniemi, John Michael (committee member).

Subjects/Keywords: Ionospheric Irregularities; Plasma Instability; GPS; SuperDARN Radar; Computational Modeling

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APA (6^th Edition):

Eltrass, A. S. H. A. (2015). The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/51804

Chicago Manual of Style (16^th Edition):

Eltrass, Ahmed Said Hassan Ahmed. “The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals.” 2015. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/51804.

MLA Handbook (7^th Edition):

Eltrass, Ahmed Said Hassan Ahmed. “The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals.” 2015. Web. 18 Jan 2021.

Vancouver:

Eltrass ASHA. The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals. [Internet] [Doctoral dissertation]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/51804.

Council of Science Editors:

Eltrass ASHA. The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals. [Doctoral Dissertation]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/51804

University of Kansas

11. McCormick, Patrick Michael. Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions.

Degree: PhD, Electrical Engineering & Computer Science, 2018, University of Kansas

URL: http://hdl.handle.net/1808/27596

► With the advancement of arbitrary waveform generation techniques, new radar transmission modes can be designed via precise control of the waveform's time-domain signal structure. The… (more)

▼ With the advancement of arbitrary waveform generation techniques, new radar transmission modes can be designed via precise control of the waveform's time-domain signal structure. The finer degree of emission control for a waveform (or multiple waveforms via a digital array) presents an opportunity to reduce ambiguities in the estimation of parameters within the radar backscatter. While this freedom opens the door to new emission capabilities, one must still consider the practical attributes for radar waveform design. Constraints such as constant amplitude (to maintain sufficient power efficiency) and continuous phase (for spectral containment) are still considered prerequisites for high-powered radar waveforms. These criteria are also applicable to the design of multiple waveforms emitted from an antenna array in a multiple-input multiple-output (MIMO) mode. In this work, three spatially-diverse radar emission design methods are introduced that provide constant amplitude, spectrally-contained waveforms implemented via a digital array radar (DAR). The first design method, denoted as spatial modulation, designs the radar waveforms via a polyphase-coded frequency-modulated (PCFM) framework to steer the coherent mainbeam of the emission within a pulse. The second design method is an iterative scheme to generate waveforms that achieve a desired wideband and/or widebeam radar emission. However, a wideband and widebeam emission can place a portion of the emitted energy into what is known as the `invisible' space of the array, which is related to the storage of reactive power that can damage a radar transmitter. The proposed design method purposefully avoids this space and a quantity denoted as the Fractional Reactive Power (FRP) is defined to assess the quality of the result. The third design method produces simultaneous radar and communications beams in separate spatial directions while maintaining constant modulus by leveraging the orthogonal complement of the emitted directions. This orthogonal energy defines a trade-space between power efficiency gained from constraining waveforms to be constant amplitude and power efficiency lost by emitting energy in undesired directions. The design of FM waveforms via traditional gradient-based optimization methods is also considered. A waveform model is proposed that is a generalization of the PCFM implementation, denoted as coded-FM (CFM), which defines the phase of the waveform via a summation of weighted, predefined basis functions. Therefore, gradient-based methods can be used to minimize a given cost function with respect to a finite set of optimizable parameters. A generalized integrated sidelobe level (GISL) metric is used as the optimization cost function to minimize the correlation range sidelobes of the radar waveform. System specific waveform optimization is explored by incorporating the linear models of three different loopback configurations into the GISL metric to match the optimized waveforms to the particular systems. Advisors/Committee Members: Blunt, Shannon D (advisor), Allen, Christopher (cmtemember), Stiles, James (cmtemember), Salandrino, Alessandro (cmtemember), Arnold, Emily (cmtemember).

Subjects/Keywords: Electrical engineering; Hardware modeling; MIMO; Optimization; Radar; RF; Waveform

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

McCormick, P. M. (2018). Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/27596

Chicago Manual of Style (16^th Edition):

McCormick, Patrick Michael. “Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions.” 2018. Doctoral Dissertation, University of Kansas. Accessed January 18, 2021. http://hdl.handle.net/1808/27596.

MLA Handbook (7^th Edition):

McCormick, Patrick Michael. “Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions.” 2018. Web. 18 Jan 2021.

Vancouver:

McCormick PM. Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions. [Internet] [Doctoral dissertation]. University of Kansas; 2018. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1808/27596.

Council of Science Editors:

McCormick PM. Design and Optimization of Physical Waveform-Diverse and Spatially-Diverse Radar Emissions. [Doctoral Dissertation]. University of Kansas; 2018. Available from: http://hdl.handle.net/1808/27596

Northeastern University

12. Wright, Christopher Franklin. Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration.

Degree: MS, Department of Civil and Environmental Engineering, 2011, Northeastern University

URL: http://hdl.handle.net/2047/d20001042

► Lack of regular maintenance programs for infrastructure systems in the United States has created a sizeable financial gap between available and required funds to keep… (more)

Subjects/Keywords: civil engineering; bridge decks; computational modeling; ground penetrating radar; Bridges - Deterioration; Bridges - Maintenance and repair; Ground penetrating radar; Civil Engineering

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APA (6^th Edition):

Wright, C. F. (2011). Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/d20001042

Chicago Manual of Style (16^th Edition):

Wright, Christopher Franklin. “Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration.” 2011. Masters Thesis, Northeastern University. Accessed January 18, 2021. http://hdl.handle.net/2047/d20001042.

MLA Handbook (7^th Edition):

Wright, Christopher Franklin. “Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration.” 2011. Web. 18 Jan 2021.

Vancouver:

Wright CF. Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration. [Internet] [Masters thesis]. Northeastern University; 2011. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2047/d20001042.

Council of Science Editors:

Wright CF. Evaluating steel-reinforced concrete bridge decks using ground-penetrating radar: models for deterioration. [Masters Thesis]. Northeastern University; 2011. Available from: http://hdl.handle.net/2047/d20001042

INP Toulouse

13. Veyssière, Gaëlle. Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties.

Degree: Docteur es, Océan, atmosphère, climat, 2019, INP Toulouse

URL: http://www.theses.fr/2019INPT0025

►

Le suivi de l’évolution du manteau neigeux est directement lié à des enjeux socio-économiques majeurs en zone de montagne. Parmi ces enjeux figure la prévision… (more)

▼

Le suivi de l’évolution du manteau neigeux est directement lié à des enjeux socio-économiques majeurs en zone de montagne. Parmi ces enjeux figure la prévision du risque d’avalanche qui s’appuie principalement sur des observations et sur la connaissance de l’état du manteau neigeux et de son évolution dans le temps. Dans cette thèse, co-financée par le CNES et par Météo- France, nous avons évalué l’apport d’observations de télédétection spatiale active micro-ondes issues du radar à synthèse d’ouverture (SAR) de Sentinel-1, pour suivre l’évolution de certaines propriétés du manteau neigeux. Dans un premier temps, nous avons évalué la chaîne de modélisation SAFRAN-ISBA/Crocus-MEMLS par rapport aux données Sentinel-1 pré-traitées sur 3 saisons hivernales de 2014 à 2017, sur une zone de 2310 km2 à 20 m de résolution dans les Alpes du Nord françaises. Nous avons montré que les données SAR étaient pertinentes pour suivre l’évolution du manteau neigeux et, avons démontré la capacité de la chaîne de modélisation à reproduire les variations du signal observé dans le temps malgré de forts biais négatifs en cas de neige humide. Nous nous sommes intéressés à la valeur ajoutée des observations SAR de Sentinel-1 pour cartographier la neige humide, c’est-à-dire, la neige avec un taux élevé d’eau liquide. Des comparaisons ont été effectuées entre les produits neige humide obtenus par Sentinel-1 et les produits neige de Sentinel-2 distribués par Theia. Cette étude a été menée sur la saison hivernale 2017-2018, qui a connu un enneigement exceptionnel. Ces travaux ouvrent la voie à l’assimilation de données de télédétection SAR dans le modèle de neige Crocus ainsi qu’à une plus grande exploitation de ces données dans le cadre du suivi de l’enneigement pour de multiples applications.

Monitoring snowpack properties in moutainous areas is directly related to major socio-economic issues. Among these issues, avalanche prediction works through a range of tools based on meteorological and snow observations and modeling. In this thesis, co-funded by the CNES and Météo-France, we evaluated the contribution of Sentinel-1 synthetic aperture radar (SAR) remote sensing observations to study the snowpack properties and the quality of the simulations for assimilation in a snowpack model. As a first step, we evaluated the SAFRAN-ISBA/Crocus- MEMLS modeling chain against pre-processed Sentinel-1 data for 3 winter seasons from 2014 to 2017 over an area of 2310 km2 in the Northern French Alps. We have shown that SAR data are relevant for monitoring snowpack evolution and demonstrated the ability of the modeling chain to reproduce observed signal variations despite strong negative bias in wet snow conditions. We focused on wet snow products derived from Sentinel-1 SAR observations in synergy with snow absence/presence products derived from visible Sentinel-2 observations. This study was conducted on the winter season 2017-2018, which was remarkable for its snow and avalanche conditions. Such combined products make it possible to follow the…

Advisors/Committee Members: Karbou, Fatima (thesis director), Morin, Samuel (thesis director).

Subjects/Keywords: Radar à synthèse d'ouverture; Manteau neigeux; Sentinel-1; Modélisation; Synthetic Aperture Radar; Snowpack; Sentinel-1; Modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Veyssière, G. (2019). Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2019INPT0025

Chicago Manual of Style (16^th Edition):

Veyssière, Gaëlle. “Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties.” 2019. Doctoral Dissertation, INP Toulouse. Accessed January 18, 2021. http://www.theses.fr/2019INPT0025.

MLA Handbook (7^th Edition):

Veyssière, Gaëlle. “Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties.” 2019. Web. 18 Jan 2021.

Vancouver:

Veyssière G. Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties. [Internet] [Doctoral dissertation]. INP Toulouse; 2019. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2019INPT0025.

Council of Science Editors:

Veyssière G. Apport des mesures du radar à synthèse d'ouverture de Sentinel-1 pour l'étude des propriétés du manteau neigeux : Contribution of the synthetic aperture radar measurements of Sentinel-1 to study the snowpack properties. [Doctoral Dissertation]. INP Toulouse; 2019. Available from: http://www.theses.fr/2019INPT0025

14. Josephine Vanaja, S. Rainfall runoff modeling using doppler weather radar data; -.

Degree: Civil Engineering, 2014, Anna University

URL: http://shodhganga.inflibnet.ac.in/handle/10603/26405

►

Precipitation is a significant input to hydrologic models so it needs to be quantified accurately A dense network of automatic rain gauges is desired to… (more)

Subjects/Keywords: Civil engineering; Doppler weather radar; Hydrologic model; Indian Remote Sensing; Rainfall estimates; Rainfall runoff modeling

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APA (6^th Edition):

Josephine Vanaja, S. (2014). Rainfall runoff modeling using doppler weather radar data; -. (Thesis). Anna University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/26405

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Josephine Vanaja, S. “Rainfall runoff modeling using doppler weather radar data; -.” 2014. Thesis, Anna University. Accessed January 18, 2021. http://shodhganga.inflibnet.ac.in/handle/10603/26405.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Josephine Vanaja, S. “Rainfall runoff modeling using doppler weather radar data; -.” 2014. Web. 18 Jan 2021.

Vancouver:

Josephine Vanaja S. Rainfall runoff modeling using doppler weather radar data; -. [Internet] [Thesis]. Anna University; 2014. [cited 2021 Jan 18]. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/26405.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Josephine Vanaja S. Rainfall runoff modeling using doppler weather radar data; -. [Thesis]. Anna University; 2014. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/26405

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

15. Vitko, Lauren Frances. PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS.

Degree: 2018, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/14754lfv104

► Subsurface restrictive layers play a crucial role in surface runoff and lateral flow processes; however, only coarse maps (scale 1: 1:12,000 - 1:63,360) are currently… (more)

▼ Subsurface restrictive layers play a crucial role in surface runoff and lateral flow processes; however, only coarse maps (scale 1: 1:12,000 - 1:63,360) are currently available through SSURGO (Soil Survey Geographic Database) portraying their depth and distribution in the landscape. High-resolution information on soil restrictive layers is urgently needed for use in hydrologic modeling and land management planning. In this dissertation, I investigate the types and distribution of soil restrictive layers and evaluate three different methods for obtaining high-resolution datasets of soil restrictive layers, including i.) the use of soil morphological features: fragic properties or fragipans (Bx horizons) and low chroma (≤ 2) depletions (LCDs) in soil cores, ii.) ground penetrating radar (GPR), and iii.) electromagnetic induction (EMI). I relate morphological indications of restriction (i.e. LCDs) to measurements of saturated hydraulic conductivity (Ksat) from borehole permeameter measurements and water table levels from shallow wells monitored over 2.5 years. I use particle size analysis to investigate the presence of a lithologic discontinuity observed during soil morphological observations. I use logistic regression and correlation to determine significant relationships between restrictive layer presence/absence and depth (determined using the three methods) and LIDAR-derived topographic variables. Topographic variables investigated include: aspect, slope, planform curvature, profile curvature, total curvature, topographic wetness index, specific contributing area, and topographic position index. The logistic regression models were evaluated based on known soil information from well-studied watersheds in the Ridge and Valley Province of Pennsylvania, wet boot mapping of saturated regions, cross-validation, a validation dataset of 112 soil cores, and comparisons to SSURGO. I found that soils containing LCDs had significantly (p = 0.003) lower Ksat (mean Ksat = 0.018 cm hr-1) than those without LCDs (mean Ksat = 2.8 cm hr-1) and that soils with LCDs had active, shallow water tables during 2.5 years of water table monitoring. I found that 87% and 27% of soil cores that were described as having fragic properties had a lithologic discontinuity at or above the Bx horizon (for FD-36 and Mattern watersheds, respectively). Particle size analysis confirmed the presence of a lithologic discontinuity; clay-free silt percent was significantly (p < 0.05) greater above the lithologic discontinuity, and rock fragment volume percent and clay-free sand percent were significantly greater (p < 0.05) below the discontinuity. Correlations between depth to Bx/LCDs and individual topographic variables (for the FD-36 and Mattern combined dataset) were very low (|r| <0.33; p < 0.05) or insignificant (p > 0.05), which suggests that a simple, linear model predicting depth to a restrictive layer is not possible based on the data collected; this may be due to different amounts and patterns of erosion and deposition between the FD-36… Advisors/Committee Members: Patrick Joseph Drohan, Dissertation Advisor/Co-Advisor, Patrick Joseph Drohan, Committee Chair/Co-Chair, Richard Charles Stehouwer, Committee Member, Peter Kleinman, Committee Member, Douglas Alan Miller, Outside Member, James Hamlett, Outside Member, Anthony Buda, Special Member.

Subjects/Keywords: soil-landscape modeling; digital soil mapping; ground penetrating radar; electromagnetic induction; soil depletions

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APA (6^th Edition):

Vitko, L. F. (2018). PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/14754lfv104

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Vitko, Lauren Frances. “PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS.” 2018. Thesis, Penn State University. Accessed January 18, 2021. https://submit-etda.libraries.psu.edu/catalog/14754lfv104.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vitko, Lauren Frances. “PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS.” 2018. Web. 18 Jan 2021.

Vancouver:

Vitko LF. PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS. [Internet] [Thesis]. Penn State University; 2018. [cited 2021 Jan 18]. Available from: https://submit-etda.libraries.psu.edu/catalog/14754lfv104.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Vitko LF. PREDICTIVE MAPPING OF SOIL RESTRICTIVE LAYERS USING TOPOGRAPHIC RELATIONSHIPS AND GEOPHYSICAL TOOLS. [Thesis]. Penn State University; 2018. Available from: https://submit-etda.libraries.psu.edu/catalog/14754lfv104

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

16. McCormick, Brian Christopher. Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD.

Degree: MS, Civil Engineering, 2003, Virginia Tech

URL: http://hdl.handle.net/10919/31621

► Precipitation and surface runoff producing mechanisms are inherently spatially variable. Many hydrologic runoff models do not account for this spatial variability and instead use "lumped"… (more)

▼ Precipitation and surface runoff producing mechanisms are inherently spatially variable. Many hydrologic runoff models do not account for this spatial variability and instead use "lumped" or spatially averaged parameters. Lumped model parameters often must be developed empirically or through optimization rather than be calculated from field measurements or existing data. Recent advances in geographic information systems (GIS) remote sensing (RS), radar measurement of precipitation, and desktop computing have made it easier for the hydrologist to account for the spatial variability of the hydrologic cycle using distributed models, theoretically improving hydrologic model accuracy. Grid based distributed models assume homogeneity of model parameters within each grid cell, raising the question of optimum grid scale to adequately and efficiently model the process in question. For a grid or raster based hydrologic model, as grid cell size decreases, modeling accuracy typically increases, but data and computational requirements increase as well. There is great interest in determining the optimal grid resolution for hydrologic models as well as the sensitivity of hydrologic model outputs to grid resolution. This research involves the application of a grid based hydrologic runoff model to the Upper Roanoke River watershed (1480km2) to investigate the effects of precipitation resolution and grid cell size on modeled peak flow, time to peak and runoff volume. The gridded NRCS curve number (CN) rainfall excess determination and ModClark runoff transformation of HEC-HMS is used in this modeling study. Model results are evaluated against observed streamflow at seven USGS stream gage locations throughout the watershed. Runoff model inputs and parameters are developed from public domain digital datasets using commonly available GIS tools and public domain modeling software. Watersheds and stream networks are delineated from a USGS DEM using GIS tools. Topographic parameters describing these watersheds and stream channel networks are also derived from the GIS. A gridded representation of the NRCS CN is calculated from the soil survey geographic database of the NRCS and national land cover dataset of the USGS. Spatially distributed precipitation depths derived from WSR-88D next generation radar (NEXRAD) products are used as precipitation inputs. Archives of NEXRAD Stage III data are decoded, spatially and temporally registered, and verified against archived IFLOWS rain gage data. Stage III data are systematically degraded to coarser resolutions to examine model sensitivity to gridded rainfall resolution. The effects of precipitation resolution and grid cell size on model outputs are examined. The performance of the grid based distributed model is compared to a similarly specified and parameterized lumped watershed model. The applicability of public domain digital datasets to hydrologic modeling is also investigated. The HEC-HMS gridded SCS CN rainfall excess calculation and ModClark… Advisors/Committee Members: Heatwole, Conrad D. (committee member), Kibler, David F. (committeecochair), Dymond, Randel L. (committeecochair).

Subjects/Keywords: Distributed Hydrologic Modeling; NEXRAD; radar; GIS

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APA (6^th Edition):

McCormick, B. C. (2003). Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/31621

Chicago Manual of Style (16^th Edition):

McCormick, Brian Christopher. “Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD.” 2003. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/31621.

MLA Handbook (7^th Edition):

McCormick, Brian Christopher. “Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD.” 2003. Web. 18 Jan 2021.

Vancouver:

McCormick BC. Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD. [Internet] [Masters thesis]. Virginia Tech; 2003. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/31621.

Council of Science Editors:

McCormick BC. Distributed Hydrologic Modeling of the Upper Roanoke River Watershed using GIS and NEXRAD. [Masters Thesis]. Virginia Tech; 2003. Available from: http://hdl.handle.net/10919/31621

17. Cavitte, Marie Genevieve P. Flow re-organization of the East Antarctic ice sheet across glacial cycles.

Degree: PhD, Geological Sciences, 2017, University of Texas – Austin

URL: http://hdl.handle.net/2152/62593

► Constraining the stability of the East Antarctic Ice Sheet (EAIS) over glacial-interglacial timescales is important to both understand its sea level contributions in the past… (more)

▼ Constraining the stability of the East Antarctic Ice Sheet (EAIS) over glacial-interglacial timescales is important to both understand its sea level contributions in the past and predict its future contributions in a warming world. Constraining how fast the EAIS can deliver ice to the ocean is as important as how much. Total volume fluctuations can be inferred through the use of nunatak exposure ages and ice core dating as well as through ice sheet modeling reconstructions of the Antarctic Ice Sheet as a whole. However, the EAIS’s ice volume fluctuations over long timescales such as 100-kyr glacial cycles and short spatial scales such as single ice flow catchment are less well known. I establish a method for dating internal reflections from ice-penetrating radar data between the Vostok and Dome C ice core sites, and determine the associated uncertainties in depth and age. I constrain the stability of two catchments of the EAIS through the use of internal stratigraphy from ice-penetrating radar, dated using correlated ice cores, combined with 1D ice flow models to reconstruct past accumulation rates. Here, I show that the ice catchment at the South Pole was highly active during the last glacial maximum while the ice dome/divide at Dome C was fairly stable during the entire last glacial cycle. Enhanced flow reaching South Pole implies the EAIS’s interior is much more susceptible to changes than previously thought. The absence of flow re-organization at Dome C for the last glacial maximum in contrast to South Pole shows that flow re-organization can vary from catchment to catchment. In addition, the stability of the Dome C region for the last 128 kyrs is highly promising for the retrieval of 1.5 million-year-old ice. 1D inversions of the deep radar isochrones interpreted above the subglacial relief of the Little Dome C (LDC) surface dome, ~30 km south of Dome C, predict several 1.5 million-year-old ice drilling sites. However, the complicated basal radar internal stratigraphy above the LDC and the presence of subglacial lakes complicate the task of choosing an ice core drill site. The EAIS-wide internal stratigraphy from the extensive modern ice-penetrating radar data now available over the EAIS have improved our understanding of its configuration and stability on multiple scales and timescales, and provide a foundation for understanding East Antarctica’s future role in global sea level change. Advisors/Committee Members: Blankenship, Donald D (advisor), Ghattas, Omar (committee member), Quinn, Terrence M (committee member), Sen, Mrinal K (committee member), Siegert, Martin J (committee member), Young, Duncan A (committee member).

Subjects/Keywords: Glaciology; Ice-penetrating radar; Isochrones; Modeling; South Pole; Dome C; Oldest Ice

10 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cavitte, M. G. P. (2017). Flow re-organization of the East Antarctic ice sheet across glacial cycles. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/62593

Chicago Manual of Style (16^th Edition):

Cavitte, Marie Genevieve P. “Flow re-organization of the East Antarctic ice sheet across glacial cycles.” 2017. Doctoral Dissertation, University of Texas – Austin. Accessed January 18, 2021. http://hdl.handle.net/2152/62593.

MLA Handbook (7^th Edition):

Cavitte, Marie Genevieve P. “Flow re-organization of the East Antarctic ice sheet across glacial cycles.” 2017. Web. 18 Jan 2021.

Vancouver:

Cavitte MGP. Flow re-organization of the East Antarctic ice sheet across glacial cycles. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2017. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2152/62593.

Council of Science Editors:

Cavitte MGP. Flow re-organization of the East Antarctic ice sheet across glacial cycles. [Doctoral Dissertation]. University of Texas – Austin; 2017. Available from: http://hdl.handle.net/2152/62593

University of Texas – Austin

18. Cavitte, Marie Genevieve P. Flow re-organization of the East Antarctic ice sheet across glacial cycles.

Degree: PhD, Geological sciences, 2017, University of Texas – Austin

URL: http://hdl.handle.net/2152/62592

► Constraining the stability of the East Antarctic Ice Sheet (EAIS) over glacial-interglacial timescales is important to both understand its sea level contributions in the past… (more)

▼ Constraining the stability of the East Antarctic Ice Sheet (EAIS) over glacial-interglacial timescales is important to both understand its sea level contributions in the past and predict its future contributions in a warming world. Constraining how fast the EAIS can deliver ice to the ocean is as important as how much. Total volume fluctuations can be inferred through the use of nunatak exposure ages and ice core dating as well as through ice sheet modeling reconstructions of the Antarctic Ice Sheet as a whole. However, the EAIS’s ice volume fluctuations over long timescales such as 100-kyr glacial cycles and short spatial scales such as single ice flow catchment are less well known. I establish a method for dating internal reflections from ice-penetrating radar data between the Vostok and Dome C ice core sites, and determine the associated uncertainties in depth and age. I constrain the stability of two catchments of the EAIS through the use of internal stratigraphy from ice-penetrating radar, dated using correlated ice cores, combined with 1D ice flow models to reconstruct past accumulation rates. Here, I show that the ice catchment at the South Pole was highly active during the last glacial maximum while the ice dome/divide at Dome C was fairly stable during the entire last glacial cycle. Enhanced flow reaching South Pole implies the EAIS’s interior is much more susceptible to changes than previously thought. The absence of flow re-organization at Dome C for the last glacial maximum in contrast to South Pole shows that flow re-organization can vary from catchment to catchment. In addition, the stability of the Dome C region for the last 128 kyrs is highly promising for the retrieval of 1.5 million-year-old ice. 1D inversions of the deep radar isochrones interpreted above the subglacial relief of the Little Dome C (LDC) surface dome, ~30 km south of Dome C, predict several 1.5 million-year-old ice drilling sites. However, the complicated basal radar internal stratigraphy above the LDC and the presence of subglacial lakes complicate the task of choosing an ice core drill site. The EAIS-wide internal stratigraphy from the extensive modern ice-penetrating radar data now available over the EAIS have improved our understanding of its configuration and stability on multiple scales and timescales, and provide a foundation for understanding East Antarctica’s future role in global sea level change. Advisors/Committee Members: Blankenship, Donald D (advisor), Ghattas, Omar (committee member), Quinn, Terrence M (committee member), Sen, Mrinal K (committee member), Siegert, Martin J (committee member), Young, Duncan A (committee member).

Subjects/Keywords: Glaciology; Ice-penetrating radar; Isochrones; Modeling; South Pole; Dome C; Oldest Ice

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cavitte, M. G. P. (2017). Flow re-organization of the East Antarctic ice sheet across glacial cycles. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/62592

Chicago Manual of Style (16^th Edition):

Cavitte, Marie Genevieve P. “Flow re-organization of the East Antarctic ice sheet across glacial cycles.” 2017. Doctoral Dissertation, University of Texas – Austin. Accessed January 18, 2021. http://hdl.handle.net/2152/62592.

MLA Handbook (7^th Edition):

Cavitte, Marie Genevieve P. “Flow re-organization of the East Antarctic ice sheet across glacial cycles.” 2017. Web. 18 Jan 2021.

Vancouver:

Cavitte MGP. Flow re-organization of the East Antarctic ice sheet across glacial cycles. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2017. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2152/62592.

Council of Science Editors:

Cavitte MGP. Flow re-organization of the East Antarctic ice sheet across glacial cycles. [Doctoral Dissertation]. University of Texas – Austin; 2017. Available from: http://hdl.handle.net/2152/62592

University of Oklahoma

19. Zhu, Ye. Radar cross section modeling of tornadic debris and applications.

Degree: PhD, 2016, University of Oklahoma

URL: http://hdl.handle.net/11244/34599

► Tornadic debris plays an important role in the study of tornadoes due to the dramatic threat it poses to human life, and the devastation it… (more)

▼ Tornadic debris plays an important role in the study of tornadoes due to the dramatic threat it poses to human life, and the devastation it causes to commercial and residential property. Radar cross section (RCS) modeling on plate-like and cylindrical objects is developed in this tornadic debris study. The sheets, plates, and cylinders used in this study are designed to represent leaves, wood board, flat building forms, metal rods, tree trunks, and branches, respectively. Different techniques are evaluated in terms of the geometry of the object, accuracy, and math complexity and computation efficiency. Geometrical Optics (GO), Geometrical Theory of Diffraction (GTD), Finite Element Method (FEM), Finite Difference Time Domain method (FDTD), Moment of Method (MoM) and Physical Optics (PO) are introduced. Finally, the decision to use PO for deriving the formulation for plate-like objects throughout the dissertation was made. Non-metal objects such as cylinder broadside, endcap, general circular sheets and plates, surface impedance circular plates, rectangular sheets and plates, as well as metal circular plates are derived by hand. Metal objects such as cylinder broadside and rectangular plates, as well as resistive rectangular thin sheet approximations, are verified and cited from published research books and papers. Full wave simulation Ansys HFSS validates the analytical results in most cases. FEKO commercial software is used to compare the analytical results for two layer plates with different media and leaf sample applications. After testing, metal vs. non-metal plates and thin vs. thick plates are distinguished by 5 dB, 10 dB, and 20 dB from the simulation results, respectively; this fact confirms the accuracy and limitations of theory. By adding endcaps, one is able to compensate the deficiency from normal to the cap surface of the finite cylinder by at least several wavelengths in length and at least half of a wavelength in radius. The theoretical analysis of the extension of PO indicates that more accurate results appear as the incident angle gets closer to normal. The errors and limitations of PO are described and demonstrated by comparison plots of analytical results vs. HFSS throughout. The leaf library and wood board (dry and wet) studies are performed as sample applications for “real” debris types under the radar coordinate transformation system for all polarizations at oblique TEM incident wave. Research questions are answered in the conclusions. Advisors/Committee Members: Cruz, J.R (advisor), Palmer, Robert (committee member), Yang, Zhibo (committee member), Fulton, Caleb (committee member), Yeary, Mark (committee member).

Subjects/Keywords: radar cross section modeling, debris scatterer, plate-like and cylindrical objects, HFSS, FEKO, modeling applications; Physical Optics technique

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APA (6^th Edition):

Zhu, Y. (2016). Radar cross section modeling of tornadic debris and applications. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/34599

Chicago Manual of Style (16^th Edition):

Zhu, Ye. “Radar cross section modeling of tornadic debris and applications.” 2016. Doctoral Dissertation, University of Oklahoma. Accessed January 18, 2021. http://hdl.handle.net/11244/34599.

MLA Handbook (7^th Edition):

Zhu, Ye. “Radar cross section modeling of tornadic debris and applications.” 2016. Web. 18 Jan 2021.

Vancouver:

Zhu Y. Radar cross section modeling of tornadic debris and applications. [Internet] [Doctoral dissertation]. University of Oklahoma; 2016. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/11244/34599.

Council of Science Editors:

Zhu Y. Radar cross section modeling of tornadic debris and applications. [Doctoral Dissertation]. University of Oklahoma; 2016. Available from: http://hdl.handle.net/11244/34599

Arizona State University

20. Kalyan, Prassana. System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR).

Degree: Engineering, 2019, Arizona State University

URL: http://repository.asu.edu/items/54922

Subjects/Keywords: Electrical engineering; Automotive Radar; Digitally Modulated Radar; PMCW radar; Simulink; spread spectrum radar; System Modeling

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APA (6^th Edition):

Kalyan, P. (2019). System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR). (Masters Thesis). Arizona State University. Retrieved from http://repository.asu.edu/items/54922

Chicago Manual of Style (16^th Edition):

Kalyan, Prassana. “System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR).” 2019. Masters Thesis, Arizona State University. Accessed January 18, 2021. http://repository.asu.edu/items/54922.

MLA Handbook (7^th Edition):

Kalyan, Prassana. “System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR).” 2019. Web. 18 Jan 2021.

Vancouver:

Kalyan P. System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR). [Internet] [Masters thesis]. Arizona State University; 2019. [cited 2021 Jan 18]. Available from: http://repository.asu.edu/items/54922.

Council of Science Editors:

Kalyan P. System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR). [Masters Thesis]. Arizona State University; 2019. Available from: http://repository.asu.edu/items/54922

21. Lobligeois, Florent. Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds.

Degree: Docteur es, Hydrologie, 2014, Paris, AgroParisTech

URL: http://www.theses.fr/2014AGPT0013

►

Les modèles hydrologiques sont des outils indispensables pour calculer les débits a l’exutoire des bassins versants, la gestion des aménagements hydrauliques ou encore la prévision… (more)

▼

Les modèles hydrologiques sont des outils indispensables pour calculer les débits a l’exutoire des bassins versants, la gestion des aménagements hydrauliques ou encore la prévision et la prévention des inondations. Les précipitations représentent la variable climatique principale à l’origine des débits des cours d’eau qui s’écoulent au sein d’un bassin versant. De ce fait, la réponse hydrologique du bassin est fortement dépendante de la représentativité des données d’entrée de précipitation.Les radars météorologiques, qui permettent aujourd’hui d’accéder a des mesures a haute résolution spatiale et temporelle des champs de précipitation, sont de plus en plus utilises dans le domaine de la prévision, pour le suivi des situations hydrométéorologiques. Cependant, la mesure des précipitations par radar est entachée d’erreurs qui peuvent affecter gravement la qualité des simulations de débit. De ce fait, l’utilisation des données de précipitations a haute résolution spatiale pour la modélisation hydrologique est souvent limitée par rapport a l’utilisation des données pluviométriques.Récemment, Météo-France a développe une réanalyse des lames d’eau au pas de temps horaire, sur une durée de 10 ans, en combinant l’ensemble des données de précipitation radar et pluviométriques : les mesures radars ont été corrigées et étalonnées avec le réseau de mesure au sol horaire et journalier. Dans cette thèse, nous proposons d’étudier l’intérêt de cette nouvelle base de données à haute résolution spatiale pour la modélisation pluie-débit.Dans un premier temps, nous avons développe et valide un modèle hydrologique semi-distribue qui a la capacité de fonctionner pour différentes résolutions spatiales, de la représentation globale jusqu’a une discrétisation spatiale très fine des bassins. Dans un deuxième temps, l’impact de la résolution spatiale des données d’entrée de précipitation sur la simulation des débits a été analysé. L’apport de l’information radar pour l’estimation des précipitations a été évalue par rapport a une utilisation exclusive des pluviomètres, par le biais de la modélisation pluie-débit en termes de précision des débits a l’exutoire des bassins. Enfin, le modèle semi-distribue TGR a été comparé avec le modèle global GRP actuellement opérationnel dans les Services de Prévision des Crues. L’originalité de notre travail réside sur l’utilisation de données d’observation sur un large échantillon de 181 bassins versants français représentant une grande diversité de tailles et conditions climatiques, ce qui nous permet d’apporter un diagnostic robuste et des éléments de réponse sur les problématiques scientifiques traitées.

Hydrologic models are essential tools to compute the catchment rainfall-runoff response required for river management and flood forecast purposes. Precipitation dominates the high frequency hydrological response, and its simulation is thus dependent on the way rainfall is represented. In this context, the sensitivity of runoff hydrographs to the spatial variability of forcing data is a major concern of…

Advisors/Committee Members: Loumagne, Cécile (thesis director), Andréassian, Vazken (thesis director).

Subjects/Keywords: Hydrologie; Modèle pluie-Débit; Précipitation radar; Prévision des crues; Spatialisation; Modélisation semi-Distributée; Hydrology; Rainfall-Runoff models; Radar rainfall data; Flood forecast; Spatialisation; Semi-Distributed modeling; 551

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lobligeois, F. (2014). Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds. (Doctoral Dissertation). Paris, AgroParisTech. Retrieved from http://www.theses.fr/2014AGPT0013

Chicago Manual of Style (16^th Edition):

Lobligeois, Florent. “Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds.” 2014. Doctoral Dissertation, Paris, AgroParisTech. Accessed January 18, 2021. http://www.theses.fr/2014AGPT0013.

MLA Handbook (7^th Edition):

Lobligeois, Florent. “Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds.” 2014. Web. 18 Jan 2021.

Vancouver:

Lobligeois F. Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds. [Internet] [Doctoral dissertation]. Paris, AgroParisTech; 2014. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2014AGPT0013.

Council of Science Editors:

Lobligeois F. Mieux connaître la distribution spatiale des pluies améliore-t-il la modélisation des crues ? Diagnostic sur 181 bassins versants français : Can we improve streamflow modeling by using higher resolution rainfall information? Diagnostic test on 181 french watersheds. [Doctoral Dissertation]. Paris, AgroParisTech; 2014. Available from: http://www.theses.fr/2014AGPT0013

Universidade Estadual de Campinas

22. Picoli, Michelle Cristina Araújo, 1981-. Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data.

Degree: 2012, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/256838

► Abstract: The sugarcane (Saccharum spp.) plays important role in economy because it is source of raw material for sugar and alcohol production. In this context… (more)

▼ Abstract: The sugarcane (Saccharum spp.) plays important role in economy because it is source of raw material for sugar and alcohol production. In this context the information needs, which enables its monitoring is very important due to allows evaluate the availability of raw material and its demands. For this, it is need a crop systematical monitoring and one of the ways to do this is through the use of remote sensing images. However, it known that it is not always possible due to the rainy season that occurs in certain periods during the crop phenological phases, impeding the acquisition of optics satellite images free of clouds. To get around this problem the use of active sensors, such as sensors of synthetic aperture radar (SAR) can help. SAR sensors can collect data in areas with frequent cloud cover and fog and can operate even at night. Therefore, this study aimed to analyze the potential of radar PALSAR/ALOS, in HH and HV polarizations, for monitoring the sugarcane crop, to determine the effects of planting rows on the backscatter and estimate sugarcane yield by means of model using radar sensor PALSAR/ALOS and agronomic data, in crop seasons: 2007/08, 2008/09, 2009/10 in northeastern region of São Paulo. The results are promising because it was able to show changing in biomass enabling the monitoring. The mean values of the backscattering coefficient (?°) from fields with perpendicular rows, in HH polarization, were higher than those from parallel rows to the range direction of the satellite (0.7 to 2.3 dB over high, 1.2 dB on average). For HV polarization, there was no statistically significant difference. The yield model estimation, explained 79%, 12% and 74% of the variation in final yield, observed in the plots, in crop seasons 2007/08, 2008/09 and 2009/10, respectively, and the model built for the three crop seasons together explained 66% . These results can be used to assist and improve the prediction of yield performed in loco, and mainly to afford an alternative for crop monitoring in some weather conditions Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Lamparelli, Rubens Augusto Camargo, 1955- (advisor), Mura, José Claudio (advisor), Universidade Estadual de Campinas. Faculdade de Engenharia Agrícola (institution), Programa de Pós-Graduação em Engenharia Agrícola (nameofprogram), Blain, Gabriel Constantino (committee member), Coutinho, Alexandre Camargo (committee member), Rocha, Jansle Vieira (committee member).

Subjects/Keywords: Sensoriamento remoto; Radar de abertura sintética; Modelagem de dados; Processamento de imagens - Métodos estatísticos; Produtividade agrícola; Remote sensing; Sinthetic aperture radar; Data modeling; Image processing - Statistical methods; Productivity agríocola

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Picoli, Michelle Cristina Araújo, 1. (2012). Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/256838

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Picoli, Michelle Cristina Araújo, 1981-. “Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data.” 2012. Thesis, Universidade Estadual de Campinas. Accessed January 18, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256838.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Picoli, Michelle Cristina Araújo, 1981-. “Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data.” 2012. Web. 18 Jan 2021.

Vancouver:

Picoli, Michelle Cristina Araújo 1. Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data. [Internet] [Thesis]. Universidade Estadual de Campinas; 2012. [cited 2021 Jan 18]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/256838.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Picoli, Michelle Cristina Araújo 1. Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar: Monitoring sugarcane with PALSAR/ALOS (L band) data. [Thesis]. Universidade Estadual de Campinas; 2012. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/256838

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

23. Ichiba, Abdellah. Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology.

Degree: Docteur es, Sciences de l'Univers et Environnement, 2016, Université Paris-Est

URL: http://www.theses.fr/2016PESC1007

► L'objectif principal de cette thèse était de parvenir à un outil de gestion fiable des bassins de rétention d'eaux pluviales en utilisant les données radar… (more)

▼ L'objectif principal de cette thèse était de parvenir à un outil de gestion fiable des bassins de rétention d'eaux pluviales en utilisant les données radar en bande X. Il s’est avéré que cela nécessite plusieurs développements de recherche. Le cas d’étude considéré comprend un bassin de 10000 m3 situé en Val-de-Marne et construit en aval d'un bassin versant urbain de 2.15 km2. Il assure un double rôle de traitement des eaux pluviales et de prévention des inondations par stockage du volume. Opérationnellement les modes de gestion associés à chacun de ces objectifs sont antagonistes si bien qu’une gestion prédictive a été mise en place ; exploitation routinière en mode anti-pollution et basculement vers le mode anti-inondation en cas de besoin. Il doit se faire sur la base d’une connaissance sûre de la situation pluvieuse prévue à court terme. Une façon courante de répondre aux besoins opérationnels de la gestion prédictive est de mettre en place un système d’alerte basé sur l’utilisation des données radar. Le système CALAMAR par exemple, repose sur l’utilisation des données radar brutes à mono polarisation du réseau radar de Météo-France; traitées avec des méthodes de conversion classiques Z-R et une calibration avec des pluviomètres. Cependant, la fiabilité de ce système fait débat, notamment vis-à-vis de la qualité de la mesure radar obtenue. Une nouvelle méthodologie de comparaison de produits radar a été développée au cours de cette thèse. Elle repose sur le cadre théorique des multifractals et permet une comparaison de la structure et de la morphologie des champs de précipitations dans l'espace et le temps à travers les échelles. Cette méthode a d'abord été appliquée sur les produits CALAMR et Météo-France, puis, pour confirmer certains des résultats, sur les premières données d’un radar bande X, acquis par l’Ecole des Ponts ParisTech dans le cadre du projet Européen RainGain et fournissant des mesures de précipitations à des échelles plus fines (jusqu’à 100m en espace et 1 min en temps). Les résultats obtenus mettent en évidence non seulement l'influence cruciale des méthodes de traitement des données brutes sur la variabilité spatio-temporelle à travers les échelles, mais permettent également de prédéfinir les conditions dans lesquelles la calibration CALAMAR peut aggraver la qualité des mesures. Elles seraient très difficiles à détecter par les méthodes classiques largement répandues, n’impliquant qu’un nombre très limité de pixels radar (seulement ceux correspondants aux pluviomètres au sol). Des extensions de la méthodologie proposée ouvriront de nouveaux horizons pour la calibration des données de pluie. Alors que la littérature scientifique, notamment autour expériences TOMACS au Japon et CASA aux Etats-Unis, souligne l’importance opérationnelle d’une mesure de pluie plus détaillée grâce au radar en bande X, son impact sur les performances des modèles hydrologiques fait encore débat. Les recherches antérieures, basée pour la plupart sur des modèles conceptuels, ne sont pas concluantes. Ainsi pour dépasser… Advisors/Committee Members: Schertzer, Daniel (thesis director).

Subjects/Keywords: Radar en bande X; Gestion prédictive; Modélisation hydrologique; Variabilité de la pluie; Analyse multifractal; X-Band radar; Predictive management; Hydrological modeling; Rainfall variability; Multifractal analysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ichiba, A. (2016). Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2016PESC1007

Chicago Manual of Style (16^th Edition):

Ichiba, Abdellah. “Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology.” 2016. Doctoral Dissertation, Université Paris-Est. Accessed January 18, 2021. http://www.theses.fr/2016PESC1007.

MLA Handbook (7^th Edition):

Ichiba, Abdellah. “Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology.” 2016. Web. 18 Jan 2021.

Vancouver:

Ichiba A. Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology. [Internet] [Doctoral dissertation]. Université Paris-Est; 2016. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2016PESC1007.

Council of Science Editors:

Ichiba A. Données radar bande X et gestion prédictive en hydrologie urbaine : X-band radar data and predictive management in urban hydrology. [Doctoral Dissertation]. Université Paris-Est; 2016. Available from: http://www.theses.fr/2016PESC1007

24. Albinet, Clément. Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements.

Degree: Docteur es, Traitement du signal et télécommunications, 2013, Rennes 1

URL: http://www.theses.fr/2013REN1S153

►

L'augmentation importante de la population mondiale, et par conséquent de ses besoins, exerce une pression de plus en plus importante sur les surfaces forestières. L'outil… (more)

▼

L'augmentation importante de la population mondiale, et par conséquent de ses besoins, exerce une pression de plus en plus importante sur les surfaces forestières. L'outil le mieux adapté au suivi des forêts, à l'échelle du globe, est la télédétection. C'est dans ce contexte que se situe ce travail de thèse, qui vise à améliorer l'estimation des paramètres biophysiques des arbres à partir de données de télédétection. L'originalité de ce travail a été d'étudier cette estimation des paramètres biophysiques en menant plusieurs études de sensibilité avec une démarche expérimentale sur des données expérimentales et sur des données simulées. Tout d'abord, l'étude s'est portée sur des séries temporelles de mesures de diffusiométrie radar obtenues sur deux sites : l'un constitué d'un cèdre en zone tempérée et l'autre d'une parcelle de forêt tropicale. Puis, cette étude de sensibilité a été poursuivie en imageant, avec une résolution élevée, plusieurs parcelles aux configurations différentes à l'intérieur d'une forêt de pin. Enfin, des données optiques et radars simulées ont été fusionnés afin d'évaluer l'apport de la fusion de données optique et radar dans l'inversion des paramètres biophysiques.

The significant increase of the world population, and therefore its needs, pushes increasingly high in forest areas. The best tool for monitoring forest across the globe is remote sensing. It is in this context that this thesis, which aims to improve the retrieval of biophysical parameters of trees from remote sensing data, takes place. The originality of this work was to study the estimation of biophysical parameters across multiple sensitivity studies on experimental data and simulated data. First, the study focused on the time series of radar scatterometry measurements obtained on two sites: one characterized by a cedar in the temperate zone and the other by a forest plot of rainforest. Then, the sensitivity analysis was continued by imaging with high resolution, several forest plots with different configurations within a pine forest. Finally, simulated radar and optical data were combined to evaluate the contribution of optical and radar data fusion in the inversion of biophysical parameters.

Advisors/Committee Members: Pottier, Éric (thesis director), Borderies, Pierre (thesis director).

Subjects/Keywords: Télédétection radar; Télédétection hyperspectrale; Forêts tropicales et tempérées; Campagnes terrain; Modélisation; Radar remote sensing; Hyperspectral remote sensing; Tropical and temperate forests; Field campaigns; Modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Albinet, C. (2013). Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements. (Doctoral Dissertation). Rennes 1. Retrieved from http://www.theses.fr/2013REN1S153

Chicago Manual of Style (16^th Edition):

Albinet, Clément. “Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements.” 2013. Doctoral Dissertation, Rennes 1. Accessed January 18, 2021. http://www.theses.fr/2013REN1S153.

MLA Handbook (7^th Edition):

Albinet, Clément. “Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements.” 2013. Web. 18 Jan 2021.

Vancouver:

Albinet C. Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements. [Internet] [Doctoral dissertation]. Rennes 1; 2013. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2013REN1S153.

Council of Science Editors:

Albinet C. Sensibilité des observables radars à la variabilité temporelle et à la configuration géométrique de forêts tempérées et tropicales à partir de mesure de proximité haute-résolution : Radar data sensitivity to the temporal variability and the geometrical configuration of temperate and tropical forests from in-situ high resolution measurements. [Doctoral Dissertation]. Rennes 1; 2013. Available from: http://www.theses.fr/2013REN1S153

25. Bousbih, Safa. Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states.

Degree: Docteur es, Surfaces et interfaces continentales, Hydrologie, 2019, Université Toulouse III – Paul Sabatier

URL: http://www.theses.fr/2019TOU30278

►

L'agriculture en Tunisie fait partie des secteurs importants sur lesquels reposent l'économie du pays. Elle revêt également son importance par sa contribution à la sécurité… (more)

▼

L'agriculture en Tunisie fait partie des secteurs importants sur lesquels reposent l'économie du pays. Elle revêt également son importance par sa contribution à la sécurité alimentaire. Dans un contexte de gestion des ressources naturelles, la caractérisation et le suivi des états de surface est indispensable, particulièrement dans les régions semi-arides où plusieurs contraintes freinent le développement agricole (période de sécheresse, conflits sur le partage des eaux, manque de ressources, surexploitations des nappes, etc.). En Tunisie, près de 80 % des ressources en eau disponibles sont utilisées par l'agriculture avec une efficacité limitée. Là, où les ressources en eau sont très limitées, l'estimation de l'état hydrique de surface est particulièrement nécessaire pour établir les décisions adéquates pour une meilleure gestion de cette ressource. Dans ce contexte, la télédétection fournit une base fondamentale de données pour l'observation de la surface et constitue un outil majeur pour l'acquisition d'informations à distance. Les travaux réalisés au cours de cette thèse sur la plaine de Kairouan, au Centre de la Tunisie et caractérisée par un climat semi aride, contribuent à l'évaluation du potentiel des nouveaux capteurs satellitaires Sentinel-1 (S-1) et Sentinel-2 (S-2) pour la caractérisation des états de surface, spécifiquement l'humidité du sol dans un contexte de gestion durable des ressources en eau et en sol. En effet, ces nouveaux systèmes offrent aujourd'hui des produits opérationnels avec une forte répétitivité temporelle et des résolutions spatiales métriques permettant un suivi régulier. Dans notre contexte, les données radars sont particulièrement sensibles aux conditions de surface, précisément à l'humidité du sol, à la rugosité de surface et à la végétation. Ils se dévoilent comme les outils les plus prometteurs pour un suivi précis à l'échelle de la parcelle ou régionale. Ce travail comprend deux principales parties qui relient directement l'humidité du sol (variable clé pour différents processus) à l'irrigation dans un premier temps, puis à la texture du sol. L'approche adoptée combine les mesures expérimentales à l'utilisation de données de la télédétection multi-capteurs en synergie, ainsi à la modélisation et à la cartographie. La thèse se structure en trois volets. Le premier volet de ce travail évalue le potentiel des données radars en bande C pour une large base de données. Les résultats ont montré à travers des études du comportement et de modélisation que le signal radar permet de suivre la dynamique temporelle et spatiale de l'humidité du sol sur des parcelles de céréales. Le second volet, consiste à évaluer l'utilisation conjointe de données optiques et radars afin de pouvoir prédire l'état hydrique de surface sur une couverture végétale.[...]

Agriculture is considered as one of the most important sectors in Tunisia on which the country's economy is predominately based. It is also important because of its contribution to food security. In the context of natural resource management,…

Advisors/Committee Members: Zribi, Mehrez (thesis director), Chabaane, Zohra Lili (thesis director).

Subjects/Keywords: Etats de surface; Humidité du sol; Télédétection; Radar; Optique; Modélisation; Synergies de données; Surface states; Soil moisture; Remote sensing; Radar; Optic; Modeling; Data synergies

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bousbih, S. (2019). Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states. (Doctoral Dissertation). Université Toulouse III – Paul Sabatier. Retrieved from http://www.theses.fr/2019TOU30278

Chicago Manual of Style (16^th Edition):

Bousbih, Safa. “Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states.” 2019. Doctoral Dissertation, Université Toulouse III – Paul Sabatier. Accessed January 18, 2021. http://www.theses.fr/2019TOU30278.

MLA Handbook (7^th Edition):

Bousbih, Safa. “Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states.” 2019. Web. 18 Jan 2021.

Vancouver:

Bousbih S. Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states. [Internet] [Doctoral dissertation]. Université Toulouse III – Paul Sabatier; 2019. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2019TOU30278.

Council of Science Editors:

Bousbih S. Synergie optique-radar pour l'estimation des états de surface continentale : Synergetic use of optical and radar for the estimation of continental surface states. [Doctoral Dissertation]. Université Toulouse III – Paul Sabatier; 2019. Available from: http://www.theses.fr/2019TOU30278

Université Catholique de Louvain

26. Lambot, Sébastien. Hydrogeophysical characterization of soil using ground penetrating radar.

Degree: 2003, Université Catholique de Louvain

URL: http://hdl.handle.net/2078.1/4591

►

The knowledge of the dynamics of soil water is essential in agricultural, hydrological and environmental engineering as it controls plant growth, key hydrological processes, and… (more)

▼

The knowledge of the dynamics of soil water is essential in agricultural, hydrological and environmental engineering as it controls plant growth, key hydrological processes, and the contamination of surface and subsurface water. Nearby remote sensing can be used for characterizing non-destructively the hydrogeophysical properties of the subsurface. In that respect, ground penetrating radar (GPR) constitutes a promising high resolution characterization tool. However, notwithstanding considerable research has been devoted to GPR, its use for assessing quantitatively the subsurface properties is constrained by the lack of appropriate GPR systems and signal analysis methods. In this study, a new integrated approach is developed to identify from GPR measurements the soil water content and hydraulic properties governing water transfer in the subsurface. It is based on hydrodynamic and electromagnetic inverse modeling. Research on GPR has focused on GPR design, forward modeling of GPR signal, and electromagnetic inversion to estimate simultaneously the depth dependent dielectric constant and electric conductivity of the shallow subsurface, which are correlated to water content and water quality. The method relies on an ultrawide band stepped frequency continuous wave radar combined with an off-ground monostatic TEM horn antenna. This radar configuration offers possibilities for real time mapping and allows for a more realistic forward modeling of the radar-antenna-subsurface system. Forward modeling is based on the exact solution of Maxwell's equations for a stratified medium. The forward model consists in elementary linear components which are linked in series and parallel. The GPR approach is validated for simple laboratory and outdoor conditions. GPR signal inversion enables the monitoring of the soil water dynamics, which can be subsequently inverted for estimating the soil hydraulic properties. A specifically designed hydrodynamic inverse modeling procedure which requires only water content data as input is further developed and validated to obtain the soil hydraulic properties under laboratory conditions.

(AGRO 3) – UCL, 2003

Advisors/Committee Members: UCL - AGRO/MILA - Département des sciences du milieu et de l'aménagement du territoire, Vanclooster, Marnik, Dufey, Joseph, Slob, Evert, Ramon, Herman, Stockbroeckx, Benoît, Vereecken, Harry, Defourny, Pierre.

Subjects/Keywords: Hydrodynamic inverse modeling; Gpr; Soil hydraulic properties; Radar antenna modeling; Soil water content; Ground penetrating radar; Hydrogeophysics; Electromagnetic inverse modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lambot, S. (2003). Hydrogeophysical characterization of soil using ground penetrating radar. (Thesis). Université Catholique de Louvain. Retrieved from http://hdl.handle.net/2078.1/4591

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lambot, Sébastien. “Hydrogeophysical characterization of soil using ground penetrating radar.” 2003. Thesis, Université Catholique de Louvain. Accessed January 18, 2021. http://hdl.handle.net/2078.1/4591.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lambot, Sébastien. “Hydrogeophysical characterization of soil using ground penetrating radar.” 2003. Web. 18 Jan 2021.

Vancouver:

Lambot S. Hydrogeophysical characterization of soil using ground penetrating radar. [Internet] [Thesis]. Université Catholique de Louvain; 2003. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2078.1/4591.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lambot S. Hydrogeophysical characterization of soil using ground penetrating radar. [Thesis]. Université Catholique de Louvain; 2003. Available from: http://hdl.handle.net/2078.1/4591

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Michigan

27. Polatin, Paul Franklin. Modeling and inversion of the radar response of vegetation canopies.

Degree: PhD, Geographic information science and geodesy, 1993, University of Michigan

URL: http://hdl.handle.net/2027.42/129223

► Modern airborne and spaceborne remote sensing radars provide an enormous amount of information about electromagnetic scattering from the earth's surface. Since a large fraction of… (more)

▼ Modern airborne and spaceborne remote sensing radars provide an enormous amount of information about electromagnetic scattering from the earth's surface. Since a large fraction of terrain is covered with vegetation having many different canopy structures and electrical properties, it is important to understand the mechanisms by which such systems scatter radiation. This should permit more effective utilization of the data acquired by such radars. The most popular method currently in use for modeling the radar response of vegetation is radiative transfer (RT). This method has the advantage of being easy to formulate and apply, which makes it convenient for use in inversion algorithms, but the fundamental underlying assumptions on which it is based also limit its applicability in the modeling of vegetation. Five chapters of this thesis are concerned with the vegetation modeling problem. Monte Carlo simulations that account for the second-order coupling between constituents are constructed for trunk dominated vegetation canopies. These simulations provide a benchmark for use in evaluating the performance of RT theory in a regime for which no other analytical models are satisfactory. The interparticle coupling models and simulations are validated using both experimental and numerical methods. A hybrid Monte Carlo/RT model for heterogeneous canopies that can be applied in cases where pure RT theory fails is developed. It is demonstrated in this work that RT theory does not properly predict the scattering behavior of canopies which have high number densities of large scatterers. It is also shown that in such cases multiple scattering and non-uniform illumination invalidate the RT concept of phase and source functions. The seventh chapter of this thesis is devoted entirely to the inverse scattering problem. An iterative inversion algorithm is formulated that may be used with any scattering model. The algorithm is applied to invert the response of the first-order RT model for a general, representative vegetation canopy. A propagation of errors analysis is provided to show the predicted response of the algorithm to errors originating from various sources. Advisors/Committee Members: Sarabandi, Kamal (advisor), Ulaby, Fawwaz T. (advisor).

Subjects/Keywords: Canopies; Electromagnetic Scattering; Inversion; Modeling; Radar; Response; Vegetation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Polatin, P. F. (1993). Modeling and inversion of the radar response of vegetation canopies. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/129223

Chicago Manual of Style (16^th Edition):

Polatin, Paul Franklin. “Modeling and inversion of the radar response of vegetation canopies.” 1993. Doctoral Dissertation, University of Michigan. Accessed January 18, 2021. http://hdl.handle.net/2027.42/129223.

MLA Handbook (7^th Edition):

Polatin, Paul Franklin. “Modeling and inversion of the radar response of vegetation canopies.” 1993. Web. 18 Jan 2021.

Vancouver:

Polatin PF. Modeling and inversion of the radar response of vegetation canopies. [Internet] [Doctoral dissertation]. University of Michigan; 1993. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2027.42/129223.

Council of Science Editors:

Polatin PF. Modeling and inversion of the radar response of vegetation canopies. [Doctoral Dissertation]. University of Michigan; 1993. Available from: http://hdl.handle.net/2027.42/129223

Texas A&M University

28. Sassen, Douglas Spencer. GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques.

Degree: PhD, Geophysics, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7307

► The presence of fractures, joints and karst features within rock strongly influence the hydraulic and mechanical behavior of a rock mass, and there is a… (more)

▼ The presence of fractures, joints and karst features within rock strongly influence the hydraulic and mechanical behavior of a rock mass, and there is a strong desire to characterize these features in a noninvasive manner, such as by using ground penetrating radar (GPR). These features can alter the incident waveform and polarization of the GPR signal depending on the aperture, fill and orientation of the features. The GPR methods developed here focus on changes in waveform, polarization or texture that can improve the detection and discrimination of these features within rock bodies. These new methods are utilized to better understand the interaction of an invasive shrub, Juniperus ashei, with subsurface flow conduits at an ecohydrologic experimentation plot situated on the limestone of the Edwards Aquifer, central Texas. First, a coherency algorithm is developed for polarimetric GPR that uses the largest eigenvalue of a scattering matrix in the calculation of coherence. This coherency is sensitive to waveshape and unbiased by the polarization of the GPR antennas, and it shows improvement over scalar coherency in detection of possible conduits in the plot data. Second, a method is described for full-waveform inversion of transmission data to quantitatively determine fracture aperture and electromagnetic properties of the fill, based on a thin-layer model. This inversion method is validated on synthetic data, and the results from field data at the experimentation plot show consistency with the reflection data. Finally, growing hierarchical self-organizing maps (GHSOM) are applied to the GPR data to discover new patterns indicative of subsurface features, without representative examples. The GHSOMs are able to distinguish patterns indicating soil filled cavities within the limestone. Using these methods, locations of soil filled cavities and the dominant flow conduits were indentified. This information helps to reconcile previous hydrologic experiments conducted at the site. Additionally, the GPR and hydrologic experiments suggests that Juniperus ashei significantly impacts infiltration by redirecting flow towards its roots occupying conduits and soil bodies within the rock. This research demonstrates that GPR provides a noninvasive tool that can improve future subsurface experimentation. Advisors/Committee Members: Everett, Mark E. (advisor), Mathewson, Christopher C. (committee member), Zhan, Honbin (committee member), Briaud, Jean-Louis (committee member), Ikelle, Luc (committee member).

Subjects/Keywords: Ground Penetrating Radar; GPR; Hydrogeology; ecohydrology; unsupervised learning; inverse modeling; image enhancement; data mining; coherency; fractures; karst

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sassen, D. S. (2011). GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7307

Chicago Manual of Style (16^th Edition):

Sassen, Douglas Spencer. “GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques.” 2011. Doctoral Dissertation, Texas A&M University. Accessed January 18, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7307.

MLA Handbook (7^th Edition):

Sassen, Douglas Spencer. “GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques.” 2011. Web. 18 Jan 2021.

Vancouver:

Sassen DS. GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7307.

Council of Science Editors:

Sassen DS. GPR Method for the Detection and Characterization of Fractures and Karst Features: Polarimetry, Attribute Extraction, Inverse Modeling and Data Mining Techniques. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7307

29. Liu, Yuan-Kai. Ground Deformation Related to Caldera Collapse and Ring-Fault Activity.

Degree: 2018, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/627773

► Volcanic subsidence, caused by partial emptying of magma in the subsurface reservoir has long been observed by spaceborne radar interferometry. Monitoring long-term crustal deformation at… (more)

▼ Volcanic subsidence, caused by partial emptying of magma in the subsurface reservoir has long been observed by spaceborne radar interferometry. Monitoring long-term crustal deformation at the most notable type of volcanic subsidence, caldera, gives us insights of the spatial and hazard-related information of subsurface reservoir. Several subsiding calderas, such as volcanoes on the Galapagos islands have shown a complex ground deformation pattern, which is often composed of a broad deflation signal affecting the entire edifice and a localized subsidence signal focused within the caldera floor. Although numerical or analytical models with multiple reservoirs are proposed as the interpretation, geologically and geophysically evidenced ring structures in the subsurface are often ignored. Therefore, it is still debatable how deep mechanisms relate to the observed deformation patterns near the surface. We aim to understand what kind of activities can lead to the complex deformation. Using two complementary approaches, we study the three-dimensional geometry and kinematics of deflation processes evolving from initial subsidence to later collapse of calderas. Firstly, the analog experiments analyzed by structure-from-motion photogrammetry (SfM) and particle image velocimetry (PIV) helps us to relate the surface deformation to the in-depth structures. Secondly, the numerical modeling using boundary element method (BEM) simulates the characteristic deformation patterns caused by a sill-like source and a ring-fault. Our results show that the volcano-wide broad deflation is primarily caused by the emptying of the deep magma reservoir, whereas the localized deformation on the caldera floor is related to ring-faulting at a shallower depth. The architecture of the ring-fault to a large extent determines the deformation localization on the surface. Since series evidence for ring-faulting at several volcanoes are provided, we highlight that it is vital to include ring-fault activity in numerical or analytical deformation source formulation. Ignoring the process of ring-faulting in models by using multiple point sources for various magma reservoirs will result in erroneous, thus meaningless estimates of depth and volume change of the magmatic reservoir(s).

Subjects/Keywords: caldera subsidence; overlapping deformation; anlog models; boundary element modeling; ring-faults; Interferometric synthetic aperture radar (SAR) (InSAR)

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liu, Y. (2018). Ground Deformation Related to Caldera Collapse and Ring-Fault Activity. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/627773

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Yuan-Kai. “Ground Deformation Related to Caldera Collapse and Ring-Fault Activity.” 2018. Thesis, King Abdullah University of Science and Technology. Accessed January 18, 2021. http://hdl.handle.net/10754/627773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Yuan-Kai. “Ground Deformation Related to Caldera Collapse and Ring-Fault Activity.” 2018. Web. 18 Jan 2021.

Vancouver:

Liu Y. Ground Deformation Related to Caldera Collapse and Ring-Fault Activity. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2018. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10754/627773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu Y. Ground Deformation Related to Caldera Collapse and Ring-Fault Activity. [Thesis]. King Abdullah University of Science and Technology; 2018. Available from: http://hdl.handle.net/10754/627773

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Northeastern University

30. Belli, Kimberly Marie. Ground penetrating radar bridge deck investigations using computational modeling.

Degree: PhD, Department of Mechanical and Industrial Engineering, 2008, Northeastern University

URL: http://hdl.handle.net/2047/d1001763x

► Infrastructure in the United States is failing. According to a 2005 study by the American Society of Civil Engineers over a quarter of the bridges… (more)

▼ Infrastructure in the United States is failing. According to a 2005 study by the American Society of Civil Engineers over a quarter of the bridges are structurally deficient or functionally obsolete. Condition assessment without the assistance of subsurface sensing techniques leads to poor detection and quantification of damage because much of the damage and precursors to damage is hidden beneath the surface. Ground Penetrating Radar (GPR) a popular choice for bridge deck assessment, depends on a subjective process, which is the trained eye of a technician. The ability to simulate a GPR investigation provides insight into the response from bridge deck elements, as well as the interaction among the elements and changes due to the presence of an anomaly and supports defect detection. A subsurface modeling tool is developed with physical modeling components available for general applications but extended to meet specific requirements for geometric modeling of civil infrastructure. The simulation component implements the 2-dimensional Finite Difference Time Domain (FDTD) method for electromagnetic modeling. Comparisons between 2D and 3D simulations show that, for bridge deck analysis, 2D modeling is adequate for condition assessment. A model-based assessment augments the conventional approach to analysis by using iterative computational models to reconstruct the bridge deck in a healthy condition. To identify areas of suspect condition, the response from the computed healthy deck can be compared to the response collected in the field. The effect of the presence of rebars on the scattering from an anomaly can be significant, and is not easily removed from GPR data. In the computational model, the strong scattering rebars are replaced with an excitation source that results in wave propagation equivalent to the scattering from the rebar. This technique makes the GPR bridge deck problem better suited to the traditional inversion algorithms that are often complicated by strong scatterers. Through experimentation, the GPR antenna can be characterized to determine a virtual sensor for the 2D FDTD model. The resulting sensor allows for a significantly smaller geometry, which saves time and computational resources while reducing differences in propagation associated with using a 2-dimensional instead of 3-dimensional model.

Subjects/Keywords: Ground penetrating radar; Computational modeling; Mechanical engineering; Industrial engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Belli, K. M. (2008). Ground penetrating radar bridge deck investigations using computational modeling. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/d1001763x

Chicago Manual of Style (16^th Edition):

Belli, Kimberly Marie. “Ground penetrating radar bridge deck investigations using computational modeling.” 2008. Doctoral Dissertation, Northeastern University. Accessed January 18, 2021. http://hdl.handle.net/2047/d1001763x.

MLA Handbook (7^th Edition):

Belli, Kimberly Marie. “Ground penetrating radar bridge deck investigations using computational modeling.” 2008. Web. 18 Jan 2021.

Vancouver:

Belli KM. Ground penetrating radar bridge deck investigations using computational modeling. [Internet] [Doctoral dissertation]. Northeastern University; 2008. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2047/d1001763x.

Council of Science Editors:

Belli KM. Ground penetrating radar bridge deck investigations using computational modeling. [Doctoral Dissertation]. Northeastern University; 2008. Available from: http://hdl.handle.net/2047/d1001763x

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