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Chen, Zhengxiao. "Microwave remote sensing of vegetation : Stochastic Lindenmayer systems, collective scattering effects, and neural network inversions /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/5854.
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Rocadenbosch, Burillo Francesc. "Lidar sensing of the atmosphere: receiver design and inversion algorithms for an elastic system." Doctoral thesis, Universitat Politècnica de Catalunya, 1996. http://hdl.handle.net/10803/6909.
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LIDAR es un acrónimo de LIght Detection And Ranging. En la presente tesis, se usan técnicas basadas en lidar elástico para monitorizar la atmósfera remotamente y derivar información cuantitativa acerca de sus parámetros ópticos. Esta tesis doctoral comprende el diseño y operación de una estación lidar elástica basada en un láser pulsado de Nd:YAG operando a las longitudes de onda de 1064 y 532 nm, en lo que se refiere a los sistemas de recepción, control y diseño de algoritmos de inversión. Básicamente, puede dividirse en tres partes bien diferenciadas: La primera (Caps. 1, 2 y 3) comprende el estudio de la dispersión elástica (Rayleigh y Mie) en la atmósfera, orientada al cálculo del balance de enlace, e intenta vislumbrar la interrelación entre variables físicas tales como la temperatura, la presión y la humedad, y el fenómeno de dispersión, dejando de lado su posible extrapolación a modelos meteorologicos. Partiendo de esta base, se estiman valores de extinción y retrodispersión para diferentes condiciones atmosféricas y, como resultado, se presenta un balance de enlace para el sistema. El mismo incluye el estudio del alcance lidar, la estimación de la relación señal a ruido, y la evaluación de fotodiodos para diferentes librerías del usuario. Esta primera parte se cierra con las especificaciones globales del sistema. La segunda parte de este trabajo (Caps. 4, 5 y 6) atiende al diseño e implemen-tación del receptor, sistemas de sincronización y control. El receptor optoelectrónico se basa en amplificadores realimentados en corriente y cuenta con un excelente producto ganancia ancho de banda. Por lo que respecta al subsistema de sincronismo, se presentan dos unidades distintas con vistas a un futuro sistema lidar de escaneo, lo cuál ofrece la posibilidad de realizar scans entrelazados. Para terminar, el sistema de control diseñado se basa en el software de control LabView, que ofrece una filosofía de control distribuido. Con este propósito, se han especificado e implementado protocolos de bus lidar y su señalización para la presente estación lidar. Finalmente, la tercera parte comprende el diseño de algoritmos de inversión con y sin memoria (Caps. 7 y 8). Los algortimos sin memoria para atmósferas homogéneas se basan en procedimientos de ajuste por regresión como son el método de la pendiente y el de mínimos cuadrados y, en el caso de atmósferas inhomogéneas, se basan en el método de Klett y calibraciones adecuadas. Los algortimos con memoria se basan en diferentes modelos estocásticos para la atmósfera y filtrado de Kalman no lineal. Además de los algortimos de inversión, también se calculan y discuten las curvas del error de inversión. El Cap. 9 describe las medidas llevadas a cabo con el sistema que este trabajo ha permitido construir así como el resultado de aplicar los algoritmos de inversión presentados en los capítulos precedentes. La inversión de escenas reales comprende estudios de la estructura de polución, estudios de nubes (ceilometría, básicamente desplazamiento y estructura de las nubes) y señala posibles fuentes de error en el factor de solapamiento.LIDAR is an acronym of LIght Detection And Ranging. In the present case, the elastic lidar techniques are used to remotely sense the atmosphere and to derive quantitative information about its optical parameters.This thesis comprises the design and operation of an elastic lidar station based on a pulsed Nd:YAG laser operating at the 1064- and 532-nm wavelengths, in the parts concerning receiver, control systems, and inversion algorithms.Basically, it can be divided in three different parts: The first one (Chaps. 1, 2, and 3) encompasses the study of the elastic scattering (Rayleigh and Mie) in the atmosphere for link-budget purposes and gives some insight into the interweaving between physical variables such as temperature, pressure and humidity, and the scattering phenomena, letting apart any possible extrapolation to meteorological models. From this basis, extinction and backscatter figures for different atmospheric conditions can readily be assessed and, as result, a system link budget is presented. This includes lidar range study, signal-to-noise ratio assessment, and photodiode evaluation from custom-made libraries. At the end of the first part, the system specification is made. The second part of this work (Chaps. 4, 5, and 6) is concerned with the design and implemen-tation of receiver, synchronization, and control systems. The optoelectronic receiver is based on current-feedback amplifiers and features a very large gain-bandwidth product. As for the synchronization subsystem, two different units are presented with a view to a future scanning lidar system, which makes room for interspersed scans. Eventually, the control system designed is LabView based and features a distributed control philosophy. For that purpose, lidar bus protocols and signals are specified and built for the actual lidar station. Finally, the third part encircles the design of inversion algorithms with and without memory (Chaps. 7 and 8). Non-memory algorithms for homogeneous atmospheres are based on regression curve-fitting procedures, such as the slope-method and the least squares while in instances of inhomogeneous atmospheres they are based on Klett's method and appropriate calibrations. Memory algorithms are based on different stochastic models for the atmosphere and on non-linear Kalman filtering. In addition to these inversion procedures, error assessment plots are also derived and discussed. Chap. 9 describes the measurements carried out with the system this work has contributed to build and the results of applying to them the inversion algorithms discussed in the preceding chapters.The inversion of live-scenes involves pollution structure studies, cloud studies (ceilometry, cloud motion and wave clouds, basically), and hints overlap factor error sources.
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Penner, Justin Frank. "Development of a Grond-Based High-Resolution 3D-SAR System for Studying the Microwave Scattering Characteristics of Trees." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2889.
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This thesis presents the development of a high-resolution ground-based 3D-SAR system and investigates its application to microwave-vegetation studies. The development process of the system is detailed including an enumeration of high-level requirements, discussions on key design issues, and detailed descriptions of the system down to a component level. The system operates on a 5.4 GHz (C-band) signal, provides a synthetic aperture area of 1.7 m x 1.7 m, and offers resolution of 0.75 m x 0.3 m x 0.3 m (range x azimuth x elevation). The system is employed on several trees with varying physical characteristics. The resulting imagery demonstrates successful 3D reconstruction of the trees and some of their internal features. The individual leaves and small branches are not visible due to the system resolution and the size of the wavelength. The foliage's outline and internal density distribution is resolved. Large branches are visible where geometry is favorable. Trunks are always visible due to their size and normal-facing incidence surface and their return has the strongest contribution from their base. The imagery is analyzed for dependencies on radar and tree parameters including: incidence angle, signal frequency, polarization, inclusion size, water content, and species. In the current work, a single frequency (5.4 GHz) and polarization (HH) is used which leaves the door open for future analysis to use other frequencies and polarizations. The improved resolution capabilities of the 3D-SAR system enables more precise backscatter measurements leading to a greater understanding of microwave-vegetation scattering behavior.
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Bismarck, Jonas von [Verfasser]. "Vibrational Raman Scattering of Liquid Water : Quantitative Incorporation into a Numeric Radiative Transfer Model of the Atmosphere-Ocean System and Analysis of its Impact on Remote Sensing Applications / Jonas von Bismarck." Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1098185447/34.
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O'Bree, Terry Adam, and s9907681@student rmit edu au. "Investigations of light scattering by Australian natural waters for remote sensing applications." RMIT University. Applied Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080110.140055.
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Remote sensing is the collection of information about an object from a distance without physically being in contact with it. The type of remote sensing of interest here is in the form of digital images of water bodies acquired by satellite. The advantage over traditional sampling techniques is that data can be gathered quickly over large ranges, and be available for immediate analysis. Remote sensing is a powerful technique for the monitoring of water bodies. To interpret the remotely sensed data, however, knowledge of the optical properties of the water constituents is needed. One of the most important of these is the volume scattering function, which describes the angular distribution of light scattered by a sample. This thesis presents the first measurements of volume scattering functions for Australian waters. Measurements were made on around 40 different samples taken from several locations in the Gippsland lakes and the Great Barrier Reef. The measurements were made by modifying an existing static light scattering spectrometer in order to accurately measure the volume scattering functions. The development of the apparatus, its calibration and automation, and the application of a complex series of post-acquisition data corrections, are all discussed. In order to extrapolate the data over the full angular range, the data was analysed using theoretical curves calculated for multi-modal size distributions using Mie light scattering theory applied to each data set. From the Mie fits the scattering and backscattering coefficients were calculated. These were compared with scattering coefficients measured using in situ sensors ac-9 and Hydroscat-6, and with values from the literature. The effect of chlorophyll a concentrations on the scattering coefficients was examined, and a brief investigation of the polarisation properties of the samples was also undertaken. Finally the angular effects on the relationship between the backscattering coefficient and the volume scattering function were investigated. This is important as in situ backscattering sensors often assume that measuring at a single fixed-angle is a good approximation for calculating the backscattering coefficient. This assumption is tested, and the optimal measurement angle determined.
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Ao, Chi On 1970. "Electromagnetic wave scattering by discrete random media with remote sensing applications." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/16782.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2001.Includes bibliographical references (p. 171-182).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
The scattering of electromagnetic waves in medium with randomly distributed discrete scatterers is studied. Analytical and numerical solutions to several problems with implications for the active and passive remote sensing of the Earth environment are obtained. The quasi-magnetostatic (QMS) solution for a conducting and permeable spheroid under arbitrary excitation is presented. The spheroid is surrounded by a weakly conducting background medium. The magnetic field inside the spheroid satisfies the vector wave equation, while the magnetic field outside can be expressed as the gradient of the Laplace solution. We solve this problem exactly using the separation of variables method in spheroidal coordinates by expanding the internal field in terms of vector spheroidal wavefunctions. The exact formulation works well for low to moderate frequencies; however, the solution breaks down at high frequency due to numerical difficulty in computing the spheroidal wavefunctions. To circumvent this difficulty, an approximate theory known as the small penetration-depth approximation (SPA) is developed. The SPA relates the internal field in terms of the external field by making use of the fact that at high frequency, the external field can only penetrate slightly into a thin skin layer below the surface of the spheroid. For spheroids with general permeability, the SPA works well at high frequency and complements the exact formulation. However, for high permeability, the SPA is found to give accurate broadband results. By neglecting mutual interactions, the QMS frequency response from a collection of conducting and permeable spheroids is also studied.
(cont.) In a dense medium, the failure to properly take into account of multiple scattering effects could lead to significant errors. This has been demonstrated in the past from extensive theoretical, numerical, and experimental studies of electromagnetic wave scattering by densely packed dielectric spheres. Here, electromagnetic wave scattering by dense packed dielectric spheroids is studied both numerically through Monte Carlo simulations and analytically through the quasi-crystalline approximation (QCA) and QCA with coherent potential (QCA-CP). We assume that the spheroids are electrically small so that single-particle scattering is simple. In the numerical simulations, the Metropolis shuffling method is used to generate realizations of configurations for non-interpenetrable spheroids. The multiple scattering problem is formulated with the volume integral equation and solved using the method of moments with electrostatic basis functions. General expressions for the self-interaction elements are obtained using the low-frequency expansion of the dyadic Green's function, and radiative correction terms are included. Results of scattering coefficient, absorption coefficient, and scattering matrix for spheroids in random and aligned orientation configurations are presented. It is shown that independent scattering approximation can give grossly incorrect results when the fractional volume of the spheroids is appreciable.
(cont.) In the analytical approach, only spheroids in the aligned configuration are solved. Low-frequency QCA and QCA-CP solutions are obtained for the average Green's function and the effective permittivity tensor. For QCA-CP, the low-frequency expansion of the uniaxial dyadic Green's function is required. The real parts of the effective permittivities from QCA and QCA-CP are compared with the Maxwell-Garnett mixing formula. ...
by Chi On Ao.
Ph.D.
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Oh, Han, and Hariharan G. Lalgudi. "Scalable Perceptual Image Coding for Remote Sensing Systems." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606208.
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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, CaliforniaIn this work, a scalable perceptual JPEG2000 encoder that exploits properties of the human visual system (HVS) is presented. The algorithm modifies the final three stages of a conventional JPEG2000 encoder. In the first stage, the quantization step size for each subband is chosen to be the inverse of the contrast sensitivity function (CSF). In bit-plane coding, two masking effects are considered during distortion calculation. In the final bitstream formation step, quality layers are formed corresponding to desired perceptual distortion thresholds. This modified encoder exhibits superior visual performance for remote sensing images compared to conventional JPEG2000 encoders. Additionally, it is completely JPEG2000 Part-1 compliant, and therefore can be decoded by any JPEG2000 decoder.
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Wanderley, Juliana Fernandes Camapum. "Colour-based recognition for remote sensing in environmental systems." Thesis, Coventry University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266844.
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Moreira, Gregori de Arruda. "Analyses of planetary boundary layer from remote sensing systems." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-15052018-122950/.
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The Planetary Boundary Layer (PBL) is a relevant part of the atmosphere with a variable extension that clearly plays an important role in fields like air quality or weather forecasting. Passive and active remote sensing systems have been widely applied to analyze PBL characteristics. The combination of different remote sensing techniques allows obtaining a complete picture on the PBL dynamic. In this study, we analyze the PBL behavior using four types of remote sensing systems: Microwave Radiometer (MWR), Elastic Lidar (EL), Doppler Lidar (DL) and Ceilometer data. The measurements were performed in two cities Granada (Spain) and São Paulo (Brazil). Firstly, at Granada, the PBL height (PBLH) obtained from MWR data is validated against PBLH provided by analyzing co-located radiosondes, showing a good agreement. In a second stage, active remote sensing systems were used for deriving the PBLH. Thus, Extended Kalman filter is applied to EL data while the vertical wind speed variance method was applied to the DL. The derived PBLH\'s by these approaches are compared to PBLH retrieved by the MWR. The results show a good agreement among the retrievals based on active remote sensing in most of the cases, although some discrepancies appear in instances of intense PBL changes (either growth and/or decrease). Then it is performed the analysis of four and five-year dataset of measurements gathered with a ceilometer and a microwave radiometer, respectively, at Granada. The methodologies applied for the PBLH detection (gradient method for ceilometer and the combination of parcel method and temperature gradient method for microwave radiometer) provided a satisfactory description of the PBL structure in simple cases. In addition, the PBL behavior is characterized by a statistical study of the convective and stable PBLH obtained from microwave radiometer measurements. The analysis of the PBLH statistical study shows some coincidence with other PBLH studies such as daily pattern, and year cycles but also some differences caused by distinct latitudes, topography and climate were found. It was performed as well a combined long-term analysis of Ceilometer retrieved Residual Layer and the Stable and Convective Layer heights determined by microwave radiometer, thus offering a complete picture of the PBL evolution by synergetic combination of remote sensing techniques. This is the reason why systems with high temporal and spatial resolution, like lidars, have been increasingly applied in studies about this atmospheric region. In this work, also was performed, at São Paulo, an analysis on lidar backscattered signal at three wavelengths (355, 532 and 1064 nm) retrieving the turbulence by the analyses of the high-order moments (variance, skewness and kurtosis) in the backscattered signal. The wavelength of 355 nm has low applicability in the proposed methodology, due to its low intensity (due to predominance of molecular backscattering) and large presence of noise, while the 532 nm wavelength showed results similar to those provided by the wavelength of 1064 nm, which was used as reference. Then, it was analyzed two case studies using the wavelengths of 532 and 1064 nm (in separately). This approach provided information about PBL height, (derived by the variance method (Menut et al., 1999), displacement of aerosol layers (skewness) and level of mixing at several heights (kurtosis). These results show the viability of the proposed methodology when the wavelengths of 532 and 1064 nm are used for the PBL description by high-order moments of the backscattered distribution. Furthermore, it is demonstrated how some variables (air temperature, aerosol concentration, vertical wind, relative humidity and net radiation) can influence the PBL dynamic with data from DL, EL and MWR at Granada. The high-order moments of the vertical velocity high frequency distributions derived from DL, and EL range corrected signal, were corrected by two methodologies (first lag and -2/3 correction). The corrected profiles present small differences when compare against the uncorrected profiles, showing low influence of noise and the viability of the proposed methodology. A detailed 2-case studies analysis was carried on, the first case corresponding to a well-defined PBL while the second one corresponds to a situation with presence of an aloft Saharan dust layer and clouds. In both cases the results provided by the different instruments ended up complementing one another, so that the synergistic use of the different systems allowed us a detailed monitoring of the PBL.A Camada Limite Planetária (PBL - Planetary Boundary Layer) é uma parte relevante da atmosfera com uma extensão variável e que claramente desempenha um papel importante em áreas de estudo, como: a qualidade do ar ou a previsão do tempo. Sistemas de sensoriamento remoto passivo e ativo têm sido amplamente utilizado para analisar as características da PBL. A combinação de diferentes técnicas de sensoriamento remoto permite obter uma imagem completa da dinâmica desta camada. Neste estudo, analisamos o comportamento da PBL utilizando quatro tipos de sistemas de sensoriamento remoto: Radiômetro de Micro-ondas (MWR), Lidar Elástico (EL), Lidar Doppler (DL) e Ceilômetro. As medições foram realizadas em duas cidades, Granada (Espanha) e São Paulo (Brasil). Primeiramente, em Granada, a altura da PBL (PBLH) obtida a partir dos dados do MWR foi validada pela PBLH gerada pela análise dos dados de radiossondas, mostrando uma boa concordância. Em um segundo estágio, sistemas ativos de sensoriamento remoto foram usados para a obtenção da PBLH. Assim, o método do filtro de Kalman foi aplicado aos dados do EL enquanto o método da variância da velocidade vertical do vento foi aplicado aos dados do DL. As PBLH derivadas dessas abordagens foram comparadas com o PBLH fornecida pelo MWR, sendo que os resultados mostram uma boa concordância na maioria dos casos, embora algumas discrepâncias apareçam nas situações de mudanças intensas da PBL (crescimento e/ou diminuição). Em seguida, é realizada a análise dos dados das medidas coletadas com um ceilômetro e um radiômetro de micro-ondas durante quatro e cinco anos, respectivamente, em Granada. As metodologias aplicadas para a detecção da PBLH (método de gradiente para o ceilômetro e a combinação do método de parcela e do método de gradiente de temperatura para o radiômetro de micro-ondas) forneceram uma descrição satisfatória da estrutura da PBL em casos simples. Além disso, o comportamento da PBL foi caracterizado por um estudo estatístico das PBLH convectiva e estável, as quais foram obtidas a partir das medidas do radiômetro de micro-ondas. A análise do estudo estatístico realizado para a PBLH mostra algumas coincidências com outros estudos já realizados para a mesma variável, como o padrão diário e os ciclos anuais. Mas também há algumas diferenças, as quais são causadas por latitudes, topografia e clima distintos. Foi realizada também uma análise combinada de longo prazo da Camada Residual (gerada pelos dados do Ceilômetro) e da Camada Estável e Convectiva (obtida pelos dados do radiômetro de micro-ondas), oferecendo assim um quadro completo da evolução da PBL por combinação sinérgica de técnicas de sensoriamento remoto. Essa é a razão pela qual sistemas com alta resolução temporal e espacial, como os lidars, têm sido cada vez mais aplicados em estudos sobre essa região atmosférica. Neste trabalho, também foi realizada, em São Paulo, uma análise do sinal retroespalhado em três comprimentos de onda (355, 532 e 1064 nm), o qual provê informações da turbulência através da análise dos momentos de alta ordem (variância, assimetria e curtose). O comprimento de onda de 355 nm apresenta pouca aplicabilidade na metodologia proposta, devido à sua baixa intensidade (por conta da predominância do retroespalhamento molecular) e grande presença de ruído, enquanto o comprimento de onda de 532 nm apresentou resultados semelhantes aos fornecidos pelo comprimento de onda de 1064 nm, o qual foi usado como referência. Em seguida, foram analisados dois estudos de caso utilizando os comprimentos de onda de 532 e 1064 nm (em separado). Essa abordagem forneceu informações sobre a altura da PBL (derivada pelo método de variância (Menut et al., 1999), deslocamento de camadas de aerossol (assimetria) e nível de mistura em várias alturas (curtose), mostrando a viabilidade da metodologia proposta, quando os comprimentos de onda de 532 e 1064 nm são usados para a descrição da PBL a partir dos momentos de alta ordem. Além disso, demonstrou-se, com dados de DL, EL e MWR obtidos em Granada, como algumas variáveis (temperatura do ar, concentração de aerossóis, vento vertical, umidade relativa e radiação líquida) podem influenciar a dinâmica da PBL. Os momentos de alta ordem das distribuições de velocidade vertical derivadas dos dados do DL e o sinal retroespalhado obtido a partir do EL foram corrigidos por duas metodologias (first lag e correção de -2/3). Os perfis corrigidos apresentam pequenas diferenças quando comparados com os perfis não corrigidos, mostrando baixa influência do ruído e a viabilidade da metodologia proposta. Foi realizada uma análise detalhada de dois estudos de casos, o primeiro correspondendo a uma PBL bem definida, enquanto o segundo corresponde a uma situação com a presença de uma camada de nuvens e poeira saariana. Em ambos os casos, os resultados fornecidos pelos diferentes instrumentos acabaram se complementando, de modo que o uso sinérgico dos diferentes sistemas nos permitiu um monitoramento detalhado da PBL.
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Thompson, James. "Identifying Subsurface Tile Drainage Systems Utilizing Remote Sensing Techniques." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1290141705.
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Dambe, Natalia. "Riverine flooding using GIS and remote sensing." Master's thesis, Faculty of Engineering and the Built Environment, 2020. https://hdl.handle.net/11427/31738.
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Floods are caused by extreme meteorological and hydrological changes that are influenced directly or indirectly by human activities within the environment. The flood trends show that floods will reoccur and shall continue to affect the livelihoods, property, agriculture and the surrounding environment. This research has analyzed the riverine flood by integrating remote sensing, Geographical Information Systems (GIS), and hydraulic and/or hydrological modeling, to develop informed flood mapping for flood risk management. The application of Hydrological Engineering Center River Analysis System (HEC RAS) and HEC HMS models, developed by the USA Hydrologic Engineering Center of the Army Corps of Engineers in a data-poor environment of a developing country were successful, as a flood modeling tools in early warning systems and land use planning. The methodology involved data collection, preparation, and model simulation using 30m Shuttle Radar Topographic Mission (SRTM) Digital Elevation Model (DEM) as a critical data input of HEC RAS model. The findings showed that modeling using HEC-RAS and HEC HMS models in a data-poor environment requires intensive data enhancements and adjustments; multiple utilization of open sources data; carrying out multiple model computation iterations and calibration; multiple field observation, which may be constrained with time and resources to get reasonable output.
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Dandini, Paolo. "Cirrus occurrence and properties determined from ground-based remote sensing." Thesis, University of Hertfordshire, 2017. http://hdl.handle.net/2299/17860.
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The ultimate application of this work is constraining the optical properties of cirrus particles, which are poorly understood, by providing an automatic method, using all-sky cameras and an infrared radiometer, to identify the occurrence of the 22° halo formed by cirrus. This is done by interpreting all sky images in terms of a scattering phase function (SPF), from which the halo ratio (HR) is calculated, and by implementing a cirrus detection algorithm to associate HR measures to ice cloud occurrences. Cirrus reflectivity at solar wavelengths is inversely related to the HR which, being an indirect measure of the regularity of the shape of the ice crystals forming the cloud, relates in turn inversely to the asymmetry parameter g. Therefore, the method proposed here to derive statistics of HRs is expected to reduce the uncertainty over the optical and microphysical properties of cirrus. The light intensity measured by the all sky camera is transformed into a scattering phase function, from which the halo formation is identified. This is done by developing image transformations and corrections needed to interpret all sky images quantitatively in terms of scattering phase function, specifically by transforming the original image from the zenith-centred to the light-source-centred system of coordinates and correcting for the air mass and for vignetting. The SPF is then determined by averaging the image brightness over the azimuth angle and the HR by calculating the ratio of brightness at two scattering angles in the vicinity of the 22° halo peak. The instrument transformation and corrections are performed using a series of Matlab scripts. Given that the HR is an ice cloud characteristic and since the method needs additional temperature information if the halo observation is to be associated with cirrus, a cirrus detection algorithm is necessary to screen out non-ice clouds before deriving reliable HR statistics. Cloud detection is determined by quantifying the temporal fluctuations of sky radiance, expressed as brightness temperature (BT), through De-trended Fluctuation Analysis and setting a clear sky fluctuation threshold. Cloud phase discrimination instead is achieved through first constructing an analytic radiative transfer model to obtain an estimate for average molecular absorption cross-section of water vapour within the spectral window of the radiometer. This is done to model the down-welling clear sky radiance, which is in turn used to correct cirrus emissivity and ultimately determine a dynamic BT threshold for the transition from ice to liquid-containing clouds. In addition to the molecular cross section the screen level air temperature and integrated water vapour are used as input parameters to the model. The utilisation of the all sky camera for such quantitative measurement was the particularly novel aspect of this work; this has not been done previously to the best of my knowledge. The cirrus detection method proposed is also innovative in that with respect to previous works it does not rely on the use of additional techniques such as LIDAR or microwave radiometry for discriminating cloud phase. Furthermore, the cirrus threshold proposed is not fixed but accounts for the attenuating properties of the atmosphere below the cloud. Once the cirrus detection algorithm is validated and cirrus occurrences determinable, the HR could be extended to estimating the asymmetry parameter and crystal roughness. These are retrievable, for instance, from in-situ observations of single ice crystal 2D scattering patterns from cloud probes of the SID (Small Ice Detector) type. This would be significant for the constraining of the optical and microphysical properties of cirrus.
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Demir, Metin Aytekin. "Perturbation theory of electromagnetic scattering from layered media with rough interfaces." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1174660001.
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Bhang, Kon Joon. "Remote Sensing Approach for Hydrologic Assessments of Complex Lake Systems." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1212787335.
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Demir, Metin A. "Perturbation theory of electromagnetic scattering from layered media with rough interfaces." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1174660001.
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Li, Wen-Hao. "Significance of multiple scattering in remotely sensed images of natural surfaces /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/6743.
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Aggarwal, Vikas. "Remote sensing and imaging in a reconfigurable computing environment." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012171.
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Almond, Simon John. "Remote sensing within GIS for woodland inventory and monitoring." Thesis, University of Portsmouth, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386832.
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Westin, Benjamin Alexander. "Applications in Remote Sensing Using the Method of Ordered Multiple Interactions." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19346.
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The Method of Ordered Multiple Interactions provides a numerical solution to the integralequations describing surface scattering which is both computationally efficient and reliably
convergent. The method has been applied in a variety of ways to solving the electromagnetic
scattering from perfectly-conducting rough surfaces. A desire to more accurately predict
the scattering from natural terrain has led to the representation of the surface material as
penetrable instead of conductive.
For this purpose, the Method of Ordered Multiple Interactions is applied to numerically
solve the electromagnetic scattering from randomly-rough dielectric surfaces. A primary
consequence of the penetrable surface material is the introduction of a pair of coupled integral equations in place of the single integral equation used to solve the problem with a perfectly conducting surface. The method is tested and analyzed by developing independent scattering solutions for canonical cases in a transform domain and by comparing results with solutions from other techniques.
The dielectric implementation of the Method of Ordered Multiple Interactions is used to solve
the electromagnetic scattering from a class of randomly-rough dielectric surfaces. This allows
for the characterization of the effect of a number of transmitter and surface parameters in the
scattering problem, observing bistatically and also specifically in the backscatter direction.
MOMI is then applied as a method to examine subsurface penetration characteristics from
a similar family of rough surfaces. Characteristics of the environment parameters and the
scattered field itself are examined, and the numerical challenges associated with observing
beneath the surface are identified and addressed.
The Method of Ordered Multiple Interactions is then incorporated as a major component of
a larger solution which computes the total scattering when a dielectric object is buried just
beneath the rough surface. This hyrid approach uses MOMI and the Method of Moments to
iteratively account for multiple interactions between the target and the dielectric interface,
enabling the study of scattering from the combined environment of a rough surface and the
embedded object, as well as the individual scattering events which combine to form the
steady-state solution.
Ph. D.
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Wallerman, Jörgen. "Remote sensing aided spatial prediction of forest stem volume /." Umeå : Dept. of Forest Resource Management and Geomatics, 2003. http://epsilon.slu.se/s271.pdf.
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Sarton, Christopher J. "Autopilot using differential thrust for ARIES autonomous underwater vehicle." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FSarton.pdf.
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Stephen, Haroon. "Microwave Remote Sensing of Saharan Ergs and Amazon Vegetation." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1461.pdf.
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Ratilal, Purnima 1971. "Remote sensing of submerged objects and geomorphology in continental shelf waters with acoustic waveguide scattering." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/91377.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2002.Includes bibliographical references (p. 347-354).
The long range imaging of submerged objects, seafloor and sub-seafloor geomorphology in continental shelf waters using an active sonar system is explored experimentally and theoretically. A unified model for 3-D object scattering and reverberation that takes into account the coupling between propagation and scattering in a stratified medium is developed from wave theory. The conditions necessary for scattering in a waveguide to become diffuse is derived directly from Green's Theorem. Simulations with the unified model indicate that the detection of submerged target echoes above diffuse seafloor reverberation is highly dependent upon waveguide properties, bandwidth, array aperture, measurement geometry, and the scattering properties of the target. Analysis with the unified model shows that it is theoretically plausible for coherent returns from the scattering of evanescent waves by extended but discrete sub-bottom geologic features to stand significantly above diffuse or incoherent returns arising from small-scale roughness of the waveguide boundaries. A long-range bistatic sonar system was deployed in a field experiment and used to image extensive networks of buried river channels and inclined sub-seafloor strata over tens of kilometers in nearreal time. Such a capability is of great advantage in geophysical applications. Since buried river channels are expected to be ubiquitous in continental shelf environments, sub-seafloor geomorphology will play a major role in producing "false alarms" or cluster in long-range sonar systems that search for submerged objects such as underwater vehicles.
(cont.) A generalized extinction theorem for object scattering in a stratified medium is derived that can be applied to detect and classify objects from the total field in the forward scatter direction in a waveguide. Analytic expressions are derived for the attenuation and dispersion in the forward propagated field due to scattering from random surface and volume inhomogeneities in a waveguide. The unified model is applied to show that the active sonar equation is not in general valid for scattering in a waveguide. It is shown that the sonar equation may be made approximately valid in a waveguide by lowering the active frequency of operation sufficiently for the given measurement scenario to simplify analysis for target classification and localization.
by Purnima Ratilal.
Ph.D.
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Dobbs, Brian M. "The incorporation of atmospheric variability into DIRSIG /." Online version of thesis, 2006. https://ritdml.rit.edu/dspace/handle/1850/3014.
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Frey, Elizabeth G. "An examination of distributional assumptions in LANDSAT TM imagery /." Online version of thesis, 1995. http://hdl.handle.net/1850/12253.
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Charlebois, Daniel. "A planning system based on plan re-use and its application to geographical information systems and remote sensing." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq20994.pdf.
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Zhang, Zhibo. "Computation of the scattering properties of nonspherical ice crystals." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1267.
Full textAbstract:
This thesis is made up of three parts on the computation of scattering properties of nonspherical
particles in the atmosphere. In the first part, a new crystal type-droxtal-is introduced to make a better
representation of the shape of small ice crystals in the uppermost portions of midlatitude and tropical cirrus
clouds. Scattering properties of droxtal ice crystals are investigated by using the Improved-Geometric Optic
(IGO) method. At the visible wavelength, due to the presence of the hexagonal structure, all elements of the
phase matrix of droxtal ice crystals share some common features with hexagonal ice crystals, such as 220
and 460 halos. In the second part of this thesis, the possibility of enhancing the performance of current
Anomalous Diffraction Theory (ADT) is investigated. In conventional ADT models, integrations are
usually carried out in the domain of the particle projection. By transforming the integration domain to the
domain of scaled projectile length, the algorithm of conventional ADT models is enhanced. Because the
distribution of scaled projectile length is independent of the particle's physical size as long as the shape
remains the same, the new algorithm is especially efficient for the calculation of a large number of particles
with the same shape but different sizes. Finally, in the third part, the backscattering properties of
nonspherical ice crystals at the 94GHz frequency are studied by employing the Finite-Difference Time-
Domain (FDTD) method. The most important factor that controls the backscattering cross section is found
to be the ratio of the volume-equal radius to the maximum dimension of the ice crystal. Substantial
differences in backscattering cross sections are found between horizontal orientated and randomly oriented
ice crystals. An analytical formula is derived for the relationship between the ice water (IWC) content and
the radar reflectivity ( e Z ). It is shown that a change to the concentration of ice crystals without any
changes on the size distribution or particle habits leads only to a linear e Z IWC - relationship. The famous
power law e Z IWC - relationship is the result of the shift of the peak of particle size distribution.
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Hong, Kan. "Remote sensing of strong emotions using electro-optical imaging technique." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/8035.
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This thesis reports a summary of the PhD programme for the assessment of person‘s emotional anxiety using Electro-optical technology. The thesis focuses mainly on the understanding of fundamental properties of physiological responses to emotional anxiety and how they can be captured by using Electro-optical (EO) imaging methods such as hyperspectral imaging (HSI) and thermal imaging (TI) techniques. The thesis summarises three main areas of work that have been undertaken by the author in the programme: (a) Experimental set up including HSI system and data acquisition software design and implementation, (b) fundamental understanding of physiological responses to emotional anxiety from the EO perspective and (c) the development of a novel remote sensing technique for the assessment of emotions without the requirement of base line information. One of our main results is to provide evidence to prove that the mean temperature in the periorbital region remains the same within 0.2°C during emotional anxiety. Furthermore, we have shown that it is the high temperature pixels within the periorbital, which increases in numbers by a huge amount after 2 minutes of the onset of anxiety. We have also developed techniques to allow the assessment anxiety without the need of base line information. The method has been tested using a sample size of about 40 subjects, and achieved promising result. Technologies for the remote sensing of heart beat rate has been in great demand, this study also involves the development of heart beat detection using TI system. Moreover, we have also attempted for the first time to sense glucose concentration from the blood sample in-vivo using HSI technique remotely.
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Licenciado, Jose Luis Alvarex-Perez. "Two novel studies of electromagnetic scattering in random media in the context of radar remote sensing." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368345.
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Álvarez-Pérez, José Luis. "Two novel studies of electromagnetic scattering in random media in the context of radar remote sensing /." Köln : DLR, Bibliotheks- und Informationswesen, 2003. http://www.gbv.de/dms/bs/toc/377331473.pdf.
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Tiemann, Christopher O. "Acoustic scattering and remote sensing in the Strait of Gibraltar : the role of internal solitary waves /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p3035909.
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Stjernman, Anders. "Design and development of a microwave multifrequency polarimetric scatterometer for biosphere remote sensing." Doctoral thesis, Umeå universitet, Rymdfysik, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-100377.
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Microwave radar and radiometer techniques are used to gather crucial information about the earth and its atmosphere. The ERS-1, JERS-1, RadarSAT and NASA’s Mission to Planet Earth projects are designed to study the changing global environment. In all these endeavors, the key instrument is the radar or scatterometer. The advantage of microwave radar is that it is hindered very little by clouds, fog or solar radiation. Polarimetrie sensors like the shuttle-borne SIR-C radar, provides additional information compared to single polarization systems. Correct interpretation of polarimetrie data necessitates proper understanding of the scattering mechanism. Thus theory of polarization synthesis is discussed. Solution to the Kennaugh eigenvalue problem for point targets is derived. Polarimetrie signatures of point targets are shown as surfaces of spherical co-ordinates based on the Poincare sphere. Statistics of the covariance matrix elements for distributed targets are presented. The main topic of this research report is the design and development of a multifrequency, polarimetrie scatterometer for biosphere remote sensing. The system was developed using a standard HP network analyzer, a crossed log-periodic dipole antenna and a reflector. The scatterometer functions in a linear polarization basis between the L- and X-bands and gathers full-polarimetric information. The standard S-parameter measurements using the network analyzer were related to surface and volume scattering coefficients of rough surface, snow cover and vegetation media. The scatterometer measurements were carried out in the frequency domain to make use of narrow band filters in the receiver chain. The fast Fourier transform was used to convert the frequency domain measurements to the time domain. The range resolution of the system was 20 cm; azimuthal and elevation resolutions are determined by the antenna beam widths. Range side lobes were reduced by making use of appropriate weighting (Kaiser-Bessel window) functions. In the process of receiver design, we developed a number of signal processing techniques which are illustrated using appropriate numerical examples. The accuracy of target characterization depends on the quality of scatterometer calibration. A novel technique to estimate the absolute gain and crosstalk of the radar system was developed. Using a distortion matrix approach, the cross-polarization response of the system was improved by 10 to 25 dB. The radar measurements were validated by comparing point target radar observations with the corresponding theoretical values. Also, measurements of fading decorrelation distance and decorrelation bandwidth of rough surfaces were in good agreement with the theory. Backscatter observations of vegetation and snow cover were comparable to earlier published values for a similar environment. Based on initial test results and operations capability, we propose to use the present scatterometer for ground-truthing in support of ERS-1 missions. Direct comparisons of electromagnetic backscatter coefficients are possible between the ERS-1 and the present scatterometer. These joint studies are beneficial for developing inverse scattering techniques, designing new experiments and calibrating ERS-1 radar systems for distributed target environments.Diss. Umeå : Umeå universitet, 1995
digitalisering@umu
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Kramer, Tyler Christian. "The Polarimetric Impulse Response and Convolutional Model for the Remote Sensing of Layered Vegetation." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/41732.
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To date, there exists no complete, computationally efficient, physics-based model to compute the radar backscatter from forest canopies. Several models attempt to predict the backscatter coefficient for random forest canopies by using the Vector Radiative Transfer (VRT) Theory with success, however, these models often rely on purely time-harmonic formulations and approximations to integrals. Forms of VRT models have recently been developed which account for a Gaussian pulse incident waveform, however, these models often rely heavily on very specific and obfuscated approximations to solve the associated integrals.
This thesis attempts to resolve this problem by outlining a method by which existing, proven, time harmonic solutions to the VRT equation can be modified to account for arbitrary pulse waveforms through simple path delay method. These techniques lend physical insight into the actual scattering mechanisms behind the returned waveform, as well as offer explanations for why approximations of previous authors' break down in certain regions. Furthermore, these radiative transfer solutions can be reformulated into a convolutional model which is capable of quickly and accurately predicting the radar return of random volumes. A brief overview of radiative transfer theory as it applies to remote sensing is also given.Master of Science
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Makkeasorn, Ammarin. "MULTISENSOR FUSION REMOTE SENSING TECHNOLOGY FOR ASSESSING MULTITEMPORAL RESPONSES IN ECOHYDROLOGICAL SYSTEMS." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4068.
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Earth ecosystems and environment have been changing rapidly due to the advanced technologies and developments of humans. Impacts caused by human activities and developments are difficult to acquire for evaluations due to the rapid changes. Remote sensing (RS) technology has been implemented for environmental managements. A new and promising trend in remote sensing for environment is widely used to measure and monitor the earth environment and its changes. RS allows large-scaled measurements over a large region within a very short period of time. Continuous and repeatable measurements are the very indispensable features of RS. Soil moisture is a critical element in the hydrological cycle especially in a semiarid or arid region. Point measurement to comprehend the soil moisture distribution contiguously in a vast watershed is difficult because the soil moisture patterns might greatly vary temporally and spatially. Space-borne radar imaging satellites have been popular because they have the capability to exhibit all weather observations. Yet the estimation methods of soil moisture based on the active or passive satellite imageries remain uncertain. This study aims at presenting a systematic soil moisture estimation method for the Choke Canyon Reservoir Watershed (CCRW), a semiarid watershed with an area of over 14,200 km2 in south Texas. With the aid of five corner reflectors, the RADARSAT-1 Synthetic Aperture Radar (SAR) imageries of the study area acquired in April and September 2004 were processed by both radiometric and geometric calibrations at first. New soil moisture estimation models derived by genetic programming (GP) technique were then developed and applied to support the soil moisture distribution analysis. The GP-based nonlinear function derived in the evolutionary process uniquely links a series of crucial topographic and geographic features. Included in this process are slope, aspect, vegetation cover, and soil permeability to compliment the well-calibrated SAR data. Research indicates that the novel application of GP proved useful for generating a highly nonlinear structure in regression regime, which exhibits very strong correlations statistically between the model estimates and the ground truth measurements (volumetric water content) on the basis of the unseen data sets. In an effort to produce the soil moisture distributions over seasons, it eventually leads to characterizing local- to regional-scale soil moisture variability and performing the possible estimation of water storages of the terrestrial hydrosphere. A new evolutionary computational, supervised classification scheme (Riparian Classification Algorithm, RICAL) was developed and used to identify the change of riparian zones in a semi-arid watershed temporally and spatially. The case study uniquely demonstrates an effort to incorporating both vegetation index and soil moisture estimates based on Landsat 5 TM and RADARSAT-1 imageries while trying to improve the riparian classification in the Choke Canyon Reservoir Watershed (CCRW), South Texas. The CCRW was selected as the study area contributing to the reservoir, which is mostly agricultural and range land in a semi-arid coastal environment. This makes the change detection of riparian buffers significant due to their interception capability of non-point source impacts within the riparian buffer zones and the maintenance of ecosystem integrity region wide. The estimation of soil moisture based on RADARSAT-1 Synthetic Aperture Radar (SAR) satellite imagery as previously developed was used. Eight commonly used vegetation indices were calculated from the reflectance obtained from Landsat 5 TM satellite images. The vegetation indices were individually used to classify vegetation cover in association with genetic programming algorithm. The soil moisture and vegetation indices were integrated into Landsat TM images based on a pre-pixel channel approach for riparian classification. Two different classification algorithms were used including genetic programming, and a combination of ISODATA and maximum likelihood supervised classification. The white box feature of genetic programming revealed the comparative advantage of all input parameters. The GP algorithm yielded more than 90% accuracy, based on unseen ground data, using vegetation index and Landsat reflectance band 1, 2, 3, and 4. The detection of changes in the buffer zone was proved to be technically feasible with high accuracy. Overall, the development of the RICAL algorithm may lead to the formulation of more effective management strategies for the handling of non-point source pollution control, bird habitat monitoring, and grazing and live stock management in the future. Soil properties, landscapes, channels, fault lines, erosion/deposition patches, and bedload transport history show geologic and geomorphologic features in a variety of watersheds. In response to these unique watershed characteristics, the hydrology of large-scale watersheds is often very complex. Precipitation, infiltration and percolation, stream flow, plant transpiration, soil moisture changes, and groundwater recharge are intimately related with each other to form water balance dynamics on the surface of these watersheds. Within this chapter, depicted is an optimal site selection technology using a grey integer programming (GIP) model to assimilate remote sensing-based geo-environmental patterns in an uncertain environment with respect to some technical and resources constraints. It enables us to retrieve the hydrological trends and pinpoint the most critical locations for the deployment of monitoring stations in a vast watershed. Geo-environmental information amassed in this study includes soil permeability, surface temperature, soil moisture, precipitation, leaf area index (LAI) and normalized difference vegetation index (NDVI). With the aid of a remote sensing–based GIP analysis, only five locations out of more than 800 candidate sites were selected by the spatial analysis, and then confirmed by a field investigation. The methodology developed in this remote sensing-based GIP analysis will significantly advance the state-of-the-art technology in optimum arrangement/distribution of water sensor platforms for maximum sensing coverage and information-extraction capacity. Effective water resources management is a critically important priority across the globe. While water scarcity limits the uses of water in many ways, floods also have caused so many damages and lives. To more efficiently use the limited amount of water or to resourcefully provide adequate time for flood warning, the results have led us to seek advanced techniques for improving streamflow forecasting. The objective of this section of research is to incorporate sea surface temperature (SST), Next Generation Radar (NEXRAD) and meteorological characteristics with historical stream data to forecast the actual streamflow using genetic programming. This study case concerns the forecasting of stream discharge of a complex-terrain, semi-arid watershed. This study elicits microclimatological factors and the resultant stream flow rate in river system given the influence of dynamic basin features such as soil moisture, soil temperature, ambient relative humidity, air temperature, sea surface temperature, and precipitation. Evaluations of the forecasting results are expressed in terms of the percentage error (PE), the root-mean-square error (RMSE), and the square of the Pearson product moment correlation coefficient (r-squared value). The developed models can predict streamflow with very good accuracy with an r-square of 0.84 and PE of 1% for a 30-day prediction.Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering PhD
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Meißner, Henry. "Determination and Improvement of Spatial Resolution obtained by Optical Remote Sensing Systems." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22348.
Full textAbstract:
Das Bereitstellen von Parametern bezüglich Auflösungsvermögen und effektiver Auflösung ist ein gut erforschtes Wissenschaftsfeld, dennoch sind noch einige offen Fragen zu klären, wenn eine standardisierte Erhebung angestrebt wird. Zu diesem Zweck ist im Rahmen der vorliegenden Arbeit ein Framework definiert und mathematisch und methodologisch beschrieben worden unter Einbeziehung aller untergeordneten Prozesse. Weiterhin liefert sie einen detaillierten Überblick zu den verwendeten Methoden und Strukturen, um räumliche Auflösung zu messen. Das zuvor definierte Framework wird darüber hinaus genutzt, um alle zugehörigen Probleme bezüglich eines genormten Prozesses zu identifizieren und zu lösen. Der so definierte Prozess ist außerdem Teil der bevorstehenden, neuen Norm: DIN 18740-8.
Im Hinblick auf die Norm sind alle Messeinflüsse an den möglichen Stellen quantifiziert worden und an Stellen, wo dies nicht möglich ist, wurden Vorkehrungen definiert, die diese Einflüsse mindern. Darüber hinaus wurde ein zugehöriges Softwaretool entwickelt, das ebenfalls die neue Norm unterstützt.
Als weiterer Schwerpunkt dieser Arbeit wurde ein Verfahren zur Verbesserung der räumlichen Auflösung entwickelt und bewertet. Das zugehörige Softwaretool kombiniert dabei verschiedene Super-Resolution-Ansätze unter Einbeziehung zusätzlicher Kenntnis über die Bildqualität.
Der neuartige Super-Resolution-Ansatz verbessert die räumliche Auflösung von Luftbildern und True-Ortho-Mosaiken indem er ein Set von niedrig aufgelösten Rohbildern, deren optimierter, äußerer und innerer Orientierung und die abgeleitete 3D-Oberfläche als Eingangsdaten akzeptiert. Anschließend werden ein oder mehrere hochaufgelöste Bilder als hybride Kombination von klassischen Super-Resolution-Methoden und De-Mosaikierung berechnet, unter Berücksichtigung der photogrammetrischen Projektionen auf die 3D-Oberfläche. Dabei werden Limitierungen der Bildkoregistrierung mit üblich verwendeten Optical-Flow-Ansätzen überwunden.Although acquisition of resolving power and effective spatial resolution is a well-studied field of research, there are still several scientific questions to be answered when it comes to a standardized determination. Therefore, this thesis provides a description of a framework for the imaging process of remote sensing sensors mathematically and methodologically including imaging components and subsequent processes. Furthermore, a detailed review for different structures and methods to measure spatial resolution is included. Aforementioned framework then is utilized to identify related issues to a standardized process obtaining spatial resolution parameters as an image quality criterion to support an upcoming standard DIN 18740-8. With respect to define the norm-procedure every measurement influence is quantified where possible and in other cases arrangements are specified to diminish their influence. Moreover, the development of an associated software measurement tool has been accomplished as part of this thesis, which also supports the norm for aerial image quality, spatial resolution in particular. As part of a further objective of this thesis, a super-resolution approach to improve spatial resolution of aerial images has been developed and evaluated. The related software tool is able to combine different super-resolution techniques and includes known image quality parameter in subsequent calculations. The novel super-resolution approach improves spatial resolution of aerial imagery and true ortho-mosaics by taking a set of multiple low-resolved raw images (color filter array), their optimized exterior and interior orientation parameters and the derived 3D-surface as input. Then, one or more super-resolved images are calculated as a hybrid of classic super-resolution method and demosaicing while considering photogrammetric back-projections onto the 3D-surface. Thereby, limitations of image co-registration with commonly used optical flow approaches can be neglected.
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Smith, H. Todd. "A systems engineering approach to designing a remote sensing satellite simulation system." Master's thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-02162010-020240/.
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Chen, Ming. "Characterization of Pedestrian Electromagnetic Scattering at 76-77GHz." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385579499.
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Almutairi, Abdullah. "An investigation of the role of image properties in influencing the accuracy of remote sensing change detection analysis." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3596.
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Thesis (Ph. D.)--West Virginia University, 2004.Title from document title page. Document formatted into pages; contains xiii, 129 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 86-95).
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Jones, Phillip J. "Cooperative area surveillance strategies using multiple unmanned systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28134.
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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Dr. George Vachtsevanos; Committee Member: Ayanna Howard; Committee Member: Dr. Thomas Michaels; Committee Member: Eric Johnson; Committee Member: Linda Wills.
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Alrowaijeh, Jamal Salem. "Fluidic Energy Harvesting and Sensing Systems." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/96241.
Full textAbstract:
Smart sensors have become and will continue to constitute an enabling technology to wirelessly connect platforms and systems and enable improved and autonomous performance. Automobiles
have about two hundred sensors. Airplanes have about eight thousand sensors. With technology advancements in autonomous vehicles or fly-by-wireless, the numbers of these sensors is expected to increase significantly. The need to conserve water and energy has led to the development of advanced metering infrastructure (AMI) as a concept to support smart energy and water grid systems that would respond to emergency shut-offs or electric blackouts. Through the Internet of things (IoT) smart sensors and other network devices will be connected to enable exchange and control procedure toward reducing the operational cost and improving the efficiency of residential and commercial buildings in terms of their function or energy and water use.
Powering these smart sensors with batteries or wires poses great challenges in terms of replacing the batteries and connecting the wires especially in remote and difficult-to-reach locations. Harvesting free ambient energy provides a solution to develop self-powered smart sensors that can support different platforms and systems and integrate their functionality. In this dissertation, we develop and experimentally assess the performance of harvesters that draw their energy from air or water flows. These harvesters include centimeter-scale micro wind turbines, piezo aeroelastic harvesters, and micro hydro generators. The performance of these different harvesters is determined by their capability to support wireless sensing and transmission, the level of generated power, and power density. We also develop and demonstrate the capability of multifunctional systems that can harvest energy to replenish a battery and use the harvested energy to sense speed, flow rate or temperature, and to transmit the data wirelessly to a remote location.PHD
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Shih, Shih-En 1964. "Direct and inverse scattering models for electromagnetic remote sensing of time-varying sea ice and snow cover." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/17461.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Vita.
Includes bibliographical references (p. 175-184).
by Shih-En Shih.
Ph.D.
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Zurk, Lisa M. "Electromagnetic wave propagation and scattering in dense, discrete random media with application to remote sensing of snow /." Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/5981.
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Huang, Junyi. "Investigation on landslide susceptibility using remote sensing and GIS methods." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/33.
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Landslides are one of the most destructive disasters that cause damage to both property and life every year. Various methodologies have been reported for landslide susceptibility mapping. Statistical methods are widely used to fit the mathematical relationship between observed landslides and the factors considered to influence the slope failure, and have shown remarkable accuracy. Among these models, frequency ratio and logistic regression models are the most popular for its simplicity and high accuracy. However, virtually all previous studies randomly extracted and reserved a portion of historical landslide records to perform the model evaluation. The purpose of this study are: 1) To produce a landslide susceptibility map for Lantau Island by GIS and remote sensing methods as well as statistical modeling techniques 2) To add extra value to the literature of evaluating their “prediction rate” (rather than “success rate”) for landslide susceptibility mapping in a temporal context. The mountainous terrain, heavy and prolonged rainfall, as well as dense development near steep hillsides make Hong Kong as one of the most vulnerable metropolitans to the risk of landslides. As there is an increasingly high demand for land resource to support the growth of economic and population, regional specific landslide susceptibility assessment in Hong Kong is necessary for hazard management and effective land use planning. Firstly, the spatial relationship among landslide occurrence and nine causative factors (elevation, slope aspect, slope gradient, plan curvature, profile curvature, NDVI, distance to river, SPI and lithology) were explored. The distribution of landslides on Lantau Island is largely governed by a combination of geo-environmental conditions, such as elevation of 200m-300m, slope gradient of 25°-35°, slope aspect of west or northwest, high degree of positive or negative plan curvature and profile curvature, sparse vegetation in terms of NDVI in 0.3-0.5 (shrub/grassland), proximity (0.6-1.2km) to fault line, presence of volcanic bedrocks (especially rhyolite lava and tuff) and high stream power index. Second, landslide susceptibility maps were generated by frequency ratio and logistic regression model, respectively. Validations of the mapping results were performed by calculating relative operating characteristics (ROC). The models, trained by 1,864 (70%) landslides records in the Enhanced Natural Terrain Landslide Inventory (ENTLI) from 2000 to 2008, were validated by subsequent 799 (30%) landslide occurred from 2008 to 2009. The validation result shows that logistic regression model (88.70%) possesses a better prediction power than frequency ratio model (78.00%) for the study area. The findings suggested that logistic regression analysis is more reliable for landslide susceptibility mapping. The resultant maps are expected to provide a scientific assessment of the risk areas with respect to landslides on Lantau Island, and to serve as a basis for decisions or justification of the Lantau development planning. Keywords: landslide susceptibility; frequency ratio; logistic regression; temporal verification; GIS; Hong Kong
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Ducey, Craig David. "Hierarchical Image Analysis and Characterization of Scaling Effects in Remote Sensing." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/399.
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The effects of scale influence all aspects of spatial analysis and should be expressly considered early in research planning. Remotely sensed images provide unique landscape perspectives and possess several features amenable to dealing with scale. In particular, images can be segmented into image objects representative of landscape features and structured as nested hierarchies for evaluating landscape patterns across a range of scales. The objectives of this research are to evaluate methods for: 1) characterizing candidate image objects to inform the selection of user-supplied segmentation parameters and 2) exploring the multi-scale structure of landscape patterns for defining and describing potentially important scales for conducting subsequent geospatial and ecological investigations. I followed a recursive strategy to develop an image hierarchy using a corrected version of the normalized difference vegetation index (NDVIc) derived from a Landsat ETM+ satellite image over a complex, forested landscape at Lava Cast Forest (LCF), Oregon. At each scale level, I calculated an objective function based on within-object variance and spatial autocorrelation to distinguish between alternative image objects created with the region-merging segmentation algorithm available in the Definiens Developer 7 software. Segmentation quality was considered highest for results exhibiting the lowest overall within-object variance and between-object spatial autocorrelation. I then applied geographical variance analysis to calculate the independent contribution and relative variability of each level in the hierarchy to evaluate the scene's spatial structure across scales. My results reveal overall trends in image object spatial variance consistent with scaling theory, but suggest judging image object quality without sampling the entire range of segmentation parameters is insufficient. Statistical limitations of the spatial autocorrelation coefficient at small sample sizes constrained the number of possible hierarchy levels within the image spatial extent, preventing identification of larger-scale landscape patterns. Geographical variance analysis results show patterns in vegetation conditions at LCF possess a multi-scaled structure. Three levels exhibiting high variance relative to the entire hierarchy coincide with abrupt transitions in the slopes of within-object variance and spatial autocorrelation trends, which I interpreted as scale thresholds potentially important for relating landscape patterns and processes. These methods provide an objective, object-oriented approach for addressing scale issues within heterogeneous landscapes using remote sensing.
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Ball, Jessica Lynne. "Field and numerical investigations of lava dome hydrothermal systems and their effects on dome stability." Thesis, State University of New York at Buffalo, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3612916.
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This study investigates the potential for hydrothermal alteration and circulation in lava domes using combined analytical, remote sensing and numerical modeling approaches. This has been accomplished in three parts: 1) A comprehensive field, geochemical and remote sensing investigation was undertaken of the hydrothermal system in the Santiaguito lava dome complex in Guatemala. The Santiaguito domes were found to contain mainly hydrous silica alteration, which is unlikely to weaken dome rock, but the summit of Santa Maria was found to contain pervasive argillic alteration (clay minerals), which do pose more of a collapse-related hazard. These results were confirmed by hot spring geochemistry which indicated that water in the domes was responsible for some rock dissolution but had a residence time too short to allow for secondary mineralization. 2) A finite element numerical modeling approach was developed which was designed to simulate the percolation of meteoric water in two dome geometries (crater-confined and 'perched'), and the results were compared to the surface expression of hydrothermal systems on existing lava domes. In both cases, we concluded that simulated domes which lacked a high-temperature (magmatic) heat source could not develop a convecting hydrothermal system and were dominated by gravitational water flow. In these low-temperature simulations, warm springs (warmer high fluid fluxes) were produced at the base of the dome talus and cool springs were dispersed lower down the slope/substrate; fumaroles (high vapor fluxes) were confined to the dome summits. Comparison with existing dome cross sections indicates that the simulations were accurate in predicting fumarole locations and somewhat accurate at predicting spring locations, suggesting that springs may be subject to permeability contrasts created by more complicated structural features than were simulated in this study. 3) The results of the numerical modeling were used to calculate alteration potential in the simulated domes, indicating the most likely areas where alteration processes might either reduce the strength of a dome or reduce permeability that could contribute to internal pressurization. Rock alteration potential in low-temperature lava domes was found to be controlled by material permeability and the presence or absence of a sustained heat source driving hydrothermal circulation. High RAI values were preserved longer in low-permeability domes, but were more strongly developed in domes with higher permeabilities. Potential for mineral dissolution was highest at the base of the dome core, while the potential for mineral precipitation is highest at the dome core-talus interface. If precipitated minerals are impermeable, the dome core/talus interface would be a likely location for accumulation of gases and initiation of gas-pressurization-related collapse; if alteration is depositing weak (i.e. clay) minerals in this area, the dome core/talus interface might be a candidate for collapses occurring as the result of alteration processes.
The results of this study are all geared toward answering two broad questions: Where are hydrothermal alteration processes likely to occur or be focused within lava domes? and What effect could these processes have on dome stability? In the specific case of the Santiaguito dome complex, the combination of a quickly-recharged, low-temperature hydrothermal system in the inactive domes actually indicated a low possibility of collapse related to alteration minerals. This result was reinforced by the results of the numerical modeling, which indicated that domes are unlikely to develop sustained hydrothermal convection without the presence of a significant (magmatic) heat source and—in the case of Santiaguito—are likely to produce more hydrous silica alteration minerals when they also lack a source of acidic gases. Models of alteration potential do detail, however, that both shallow and deep dome collapses are still a possibility with a low-temperature hydrothermal system, given either a) a source of acidic gases to drive the formation of clay minerals (which are most likely to be deposited at the core/talus interface of a dome, or b) enough deposition of silica minerals in pore spaces to lower permeability in dome rock and promote internal gas pressurization. The results of this study are not limited to lava domes, as the volcanic edifices on which they rest are composed of the same materials that comprise lava domes and are therefore susceptible to the same hydrothermal processes. Further simulations of both lava domes and their associated edifices, including mineral species models, could help constrain under what conditions a lava dome or volcano is likely to develop areas of weak mineral precipitates (such as clay minerals) which could provide sites for collapse, or develop an impermeable cap of silicate minerals which could trap rising vapor and contribute to the pressurization of the edifice in question (which can in turn lead to collapse).
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Bryant, Roderick C. "Optimal systems for echo-location /." Title page, abstract and table of contents only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phb915.pdf.
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Al-Rousan, Naief Mahmoud. "System calibration, geometric accuracy testing and validation of DEM and orthoimage data extracted from spot stereo-pairs using commercially available image processing systems." Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264262.
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Prasert, Sunyaruk. "Multi angle imaging with spectral remote sensing for scene classification." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Mar%5FPrasert.pdf.
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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, March 2005.Thesis Advisor(s): Richard C. Olsen. Includes bibliographical references (p. 95-97). Also available online.
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Tyoda, Zipho. "Landslide susceptibility mapping : remote sensing and GIS approach." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79856.
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Thesis (MSc)--Stellenbosch University, 2013.Landslide susceptibility maps are important for development planning and disaster management. The current synthesis of landslide susceptibility maps largely applies GIS and remote sensing techniques. One of the most critical stages on landslide susceptibility mapping is the selection of landslide causative factors and weighting of the selected causative factors, in accordance to their influence to slope instability. GIS is ideal when deriving static factors i.e. slope and aspect and most importantly in the synthesis of landslide susceptibility maps. The integration of landslide causative thematic maps requires the selection of the weighting method; in order to weight the causative thematic maps in accordance to their influence to slope instability. Landslide susceptibility mapping is based on the assumption that future landslides will occur under similar circumstances as historic landslides. The weight of evidence method is ideal for landslide susceptibility mapping, as it calculates the weights of the causative thematic maps using known landslides points. This method was applied in an area within the Western Cape province of South Africa, the area is known to be highly susceptible to landslide occurrences. A prediction rate of 80.37% was achieved. The map combination approach was also applied and achieved a prediction rate of 50.98%. Satellite remote sensing techniques can be used to derive the thematic information needed to synthesize landslide susceptibility maps and to monitor the variable parameters influencing landslide susceptibility. Satellite remote sensing techniques can contribute to landslide investigation at three distinct phases namely: (1) detection and classification of landslides (2) monitoring landslide movement and identification of conditions leading up to an event (3) analysis and prediction of slope failures. Various sources of remote sensing data can contribute to these phases. Although the detection and classification of landslides through the remote sensing techniques is important to define landslide controlling parameters, the ideal is to use remote sensing data for monitoring of areas susceptible to landslide occurrence in an effort to provide an early warning. In this regard, optical remote sensing data was used successfully to monitor the variable conditions (vegetation health and productivity) that make an area susceptible to landslide occurrence.
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Sahar, Liora. "Using remote-sensing and gis technology for automated building extraction." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/37231.
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Extraction of buildings from remote sensing sources is an important GIS application and has been the subject of extensive research over the last three decades. An accurate building inventory is required for applications such as GIS database maintenance and revision; impervious surfaces mapping; storm water management; hazard mitigation and risk assessment. Despite all the progress within the fields of photogrammetry and image processing, the problem of automated feature extraction is still unresolved.
A methodology for automatic building extraction that integrates remote sensing sources and GIS data was proposed. The methodology consists of a series of image processing and spatial analysis techniques. It incorporates initial simplification procedure and multiple feature analysis components. The extraction process was implemented and tested on three distinct types of buildings including commercial, residential and high-rise. Aerial imagery and GIS data from Shelby County, Tennessee were identified for the testing and validation of the results. The contribution of each component to the overall methodology was quantitatively evaluated as relates to each type of building. The automatic process was compared to manual building extraction and provided means to alleviate the manual procedure effort.
A separate module was implemented to identify the 2D shape of a building. Indices for two specific shapes were developed based on the moment theory. The indices were tested and evaluated on multiple feature segments and proved to be successful.
The research identifies the successful building extraction scenarios as well as the challenges, difficulties and drawbacks of the process. Recommendations are provided based on the testing and evaluation for future extraction projects.