Esta dissertação tem como objetivo o estudo da altimetria e do modelo geoidal no Estado de São Paulo. Para isso, uma abordagem detalhada do Problema de Valor de Contorno da Geodésia foi realizada. Além disso, são apresentados conceitos relacionados ao sistema de altitudes e a determinação das ondulações geoidais. Uma investigação do movimento e deslocamento vertical da crosta terrestre por meio do processamento preciso por ponto de duas estações de monitoramento contínuo (Cananeia NEIA e Ubatuba UBAT), localizadas no litoral paulista, foi efetuada. Constatou-se uma similaridade nos resultados por meio da comparação com o processamento feito pelo IBGE. A comparação envolvendo o Nível Médio dos Mares de duas estações maregráficas com relação ao nivelamento advindo de Imbituba foi outro estudo executado, onde a diferença após algumas correções foi de 0,34 cm. Uma análise a partir de 199 estações GPS sobre nivelamento foi realizada para comparação da ondulação geoidal com as anomalias de altura. As anomalias foram calculadas a partir dos modelos do geopotencial (EIGEN-GL04, EIGEN-5C e EGM08 para diferentes valores de grau e ordem). Os modelos que apresentaram melhor consistência com as estações GPS sobre nivelamento foram o EIGEN-GL04C e EIGEN-5C grau e ordem 360 e o EGM08 grau e ordem 360 e 2160. O modelo geoidal do Estado de São Paulo foi gerado para um modelo digital de 5. Utilizou-se a integral modificada de Stokes a partir do pacote computacional canadense SHGEO para o cálculo da componente de curto comprimento de onda. Foram empregados dados gravimétricos já existentes e dados advindos dos trabalhos de campo referentes ao Projeto Temático da FAPESP. No cálculo da componente de médio e longo comprimento de onda foi utilizado o modelo do geopotencial EGM08 (grau e ordem 150). A comparação com os dados GPS sobre nivelamento apresentou média de -0,22 m e RMSD 0,21 m. A escolha do Estado de São Paulo está relacionada à grande quantidade de trabalhos geodésicos e atividades na área da engenharia e que necessitam da utilização de um sistema altimétrico. Além disso, a grande quantidade de dados gravimétricos e de estações GPS/RN é mais uma justificativa para a realização do trabalho no Estado. / The investigation of the altimetry and the geoid model in São Paulo state is the aim of this dissertation. A detailed study concerning the Geodetic Boundary Value Problem was carried out. Moreover, the concepts related to the height system are presented. The analysis of the crust vertical displacement involving two continuous monitoring GPS stations (Cananeia NEIA and Ubatuba UBAT) in the coast of the state was performed. It was detected similar results between the comparison involved IBGE processing. A comparison involving the mean sea level of two tide gauge stations with respect to levelling from Imbituba was carried out. After some corrections the difference found was 0.34 m. A comparison between height anomalies by the Global Geopotential Models (EIGEN-GL04, EIGEN-5C and EGM08 for different degree and order) and 199 GPS observations on Bench Marks of the spirit leveling network was performed. The Global Geopotential Models that presented consistency with GPS on Bench Marks were: EIGEN-GL04C and EIGEN- 5C degree and order 360 and EGM08 degree and order 2160. São Paulo state geoid model was computed in 5 digital model. The modified Stokes integral by the Canadian package SHGEO to compute the short wavelength component was used, from Helmert gravity anomalies derived. Existing gravity data and data from FAPESP Thematic Project was processed. EGM08 model was used as a reference field restricted to degree and order 150 to obtain the long and medium wavelength components. The comparison with GPS on Bench Marks presented mean -0.22 m and RMSD 0.21 m. The reason for the choice of São Paulo state is that there are a lot of geodetic activities and important engineering works that require the use of a height system. Furthermore, there are a lot of gravimetric and GPS/BM data all around the state.

A crescente demanda por informações gravimétricas consistentes em âmbito sul-americano, visando, sobretudo, a unificação de um sistema altimétrico para o continente, foi a motivação maior deste trabalho. Nesse contexto, procurou-se evidenciar informações detalhadas, de cunho técnico e operacional, voltadas à execução de levantamentos gravimétricos. Assim, conceitos básicos introdutórios seguidos de uma resenha histórica da gravimetria no Brasil e no mundo, são delineados. É efetuada a proposta de uma nova abordagem para um sistema gravimétrico. Apresentam-se aspectos práticos detalhados sobre o manuseio do gravímetro LaCoste & Romberg. Sugerem-se, adicionalmente, procedimentos metodológicos para as diversas etapas de uma operação gravimétrica. Ao final, à guisa de estudo de caso, disponibilizam-se resultados que são analisados e comparados. / The increasing demand for consistent South American gravimetric informations, aiming, most of all, the unification of a height system for the continent, was the motivation for this work. Within this context, an effort was made to evince detailed technical and operational informations related to the execution of gravimetric surveys. Basic concepts are exposed, followed by a historical summary of gravimetry in Brazil and throughout the world. A proposal of a new approach for a gravimetric system is made and detailed practical aspects on the use of LaCoste & Romberg gravity meter are given. In addition, methodological procedures are suggested for the several stages of a gravimetric operation. Finally, as a case study, results are made available after analysis and comparisons.

<p> In this thesis, path planning for an autonomous ground vehicle (AGV) in an urban environment is considered. The following problem is considered. starting from an initial location, the AGV desires to reach a final location by taking the shortest distance, while minimizing the AGVs position estimation error and guaranteeing that the AGVs position estimation uncertainty is below a desired threshold. The AGV is assumed to be equipped with receivers capable of producing pseudodange measurements on Global Navigation Satellite System (GNSS) satellites and cellular long-term evolution (LTE) towers. Using a geographic information system (GIS) three-dimensional (3-D) building map of the urban environment, a signal reliability map is introduced, which provides information about regions where large errors due to cellular signal multipath or poor GNSS line-of-sight (LOS) are expected. The vehicle uses the signal reliability map to calculate the position estimation mean-squared error (MSE). An analytical expression for the AGV's state estimates is derived for a weighted nonlinear least-squares (WNLS) estimator, which is used to find an analytical upper bound on the position bias due to multipath. A path planning approach based on Dijkstra's algorithm is proposed to optimize the AGV's path while minimizing the path length and the position estimation MSE, subject to keeping the position estimation uncertainty and position estimation bias due to multipath being below desired thresholds. The path planning approach yields the optimal path together with a list of feasible paths. Simulation results are presented demonstrating that utilizing ambient cellular LTE signals together with GNSS signals (1) reduces the uncertainty about the AGV's position, (2) increases the number of feasible paths to choose from, which could be useful if other considerations arise, e.g., traffic jams and road blockages due to construction, and (3) yields significantly shorter feasible paths, which would otherwise be infeasible with GNSS signals alone. Experimental results on a ground vehicle navigating in downtown Riverside, California, are presented demonstrating a close match between the simulated and experimental results.</p><p>

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 334-349). Available also in a digital version from Dissertation Abstracts.

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

<p> Since the late eighties, an ever increasing number of American craft breweries have opened up across the United States. Although the industry has a relatively high success rate, there are still a number of craft breweries that fail. As craft brewing is an inherently location based business, the sites selected for new brewery locations are important to that business&rsquo;s success. This research aims to examine how geodemographic information plays a role in strategic location decisions for craft breweries. By building a consumer profile for Phoenix craft brewery customers and comparing the results to the actual demographics of trade areas surrounding craft breweries, we begin to get a picture of geodemographics role in the site selection process. The research looks specifically at two locations; Bad Water Brewing Company and a site they are interested in acquiring. An analysis is performed to compare the geodemographic and behaviors of craft beer consumers in Phoenix, Arizona and those of the Bad Water Brewing location and their potential new site. This analysis ultimately results in intelligent business information related to location. The information compiled in this study can be used to make informed site selection decisions.</p>

<p> Light Detection And Ranging (LiDAR) data can be used to accurately model three- dimensional surfaces for quantifying fluvial erosion and deposition. Terrestrial LiDAR is typically used for monitoring banks, but can be used for monitoring planar forms such as point bars. Point bars are topographic features that form on the convex bank of a meander. While point bars are considered to be formed by depositional processes, they display features such as chute channels and scour holes that suggest that erosion, due to high flow events, may significantly influence point bar evolution. Through the use of Terrestrial Laser Scanning (TLS), we observed how a point bar on the White Clay Creek near Newark, Delaware, responded to a flood event with a return period of 6.1 years, and to multiple small events over a 1 year period with return periods between 1.00 and 1.25 years. Scans of the point bar were completed on April 11, 2014, May 8, 2014, and April 16, 2015. Scans were referenced to a common coordinate system, scan data representing vegetation points were removed, and three 0.1 m x 0.1 m gridded Digital Elevation Models (DEMs) were created from the remaining data. DEMs of Difference (DoDs) were calculated by subtracting the cell values in subsequent DEMs and by thresholding out positional and surface roughness errors. The 6.1 year flood that occurred between the April 11, 2014 scan and the May 8, 2014 scan resulted in 88.53 m³ of erosion and 39.12 m³ of deposition. The net volumetric change was -49.40 m³ over an area of 631.72 m². The smaller events that occurred between the May 8, 2014 scan and the April 16, 2015 scan resulted in 13.33 m³ of erosion and 53.46 m³ of deposition. The net volumetric change was x i 40.13 m³ over an area of 620.74 m². Our results suggest that 1) sediment deposited on point bars is eroded frequently by flood events; and 2) TLS can provide useful estimates of erosion and deposition. Although our results are for a short period, longer datasets can be used to calculate sediment residence times for point bar deposits. Additionally, we can gain a better understanding of how point bar deposits are preserved in the geologic record. This information is useful for creating accurate sediment budgets, remediating contamination issues, and interpreting geologic history.</p>

<p> This survey study examines cell phone usage data and focuses on the application of the data to disaster response management. Through the course of this study, the structure of cell phone usage data and its characteristics will be reviewed. Cell phone usage data provides us with valuable information about human movements and their activities. The uniqueness of the data is that it contains both spatial and temporal information and this information is free of fixed routes such as roads or any preset data capturing timing. In short, it is a very fluid kind of data which reflects our activities as humans with freedom of movement. Depending on data extraction methods, the data server can provide additional information such as application activities, battery level and charge activities. However, cell phone usage data contains shortcomings including data inconsistency and sparseness. Both the richness and the shortcomings of the data expose the hurdles required in data processing and force us to devise new ways to analyze this kind of data. Once the data has been properly analyzed, the findings can be applied to our real life problems including disaster response. By understanding human movement patterns using cell phone usage data, we will be able to allocate limited emergency resources more adequately. Even more, when disaster victims lose their cell phone functionality during a disaster, we might be able to identify or predict the locations of victims or evacuees and supply them with necessary assistance. The results of this study provide some insights to cell phone usage data and human movement patterns including the concentration of cell phone activities in specific zones and rather universal cell phone charging patterns. The potential of the data as a movement analysis resource and the application to disaster response is apparent. As a base to leverage the study to the next level, a possible conceptual model of human movement factors and data processing methods will be presented.</p>

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

<p>This study involves creating archaeological predictive models (APMs) for Bradford County, Pennsylvania: a known site model, a regression analysis model, and a multi-criteria analysis model. The APMs show the areas of highest sensitivity for archaeological sites but utilize different methods so that the models can be compared. The thesis also compares locations of known archaeological sites and the areas of high archaeological probability to natural gas well sites to determine the impact of natural gas drilling on the archaeological record. Finally, the thesis addresses whether new archaeological sites can be located using different types of remote sensing. The goal of this study is to provide a planning strategy for the protection of cultural resources. The Commonwealth of Pennsylvania statewide historic plan for 2012-2017 calls for the creation of a statewide archaeological probability map. This study provides a baseline for the future creation of predictive models for the state of Pennsylvania.