Texas A&M University at College Station
Permanent URI for this collectionhttps://hdl.handle.net/2249.1/23606
Texas A&M University is a land-grant, sea-grant and space-grant institution located in College Station, Texas. The university’s enrollment includes approximately 44,000 students studying for degrees in 10 academic colleges. This collection contains the theses and dissertations produced at A&M since 2002.
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Item 1,1-bis(3-indolyl)-1-(p-substitutedphenyl) methanes induce apoptosis and inhibit renal cell carcinoma growth(2009-06-02) York, Melissa DawnRenal cell carcinoma (RCC) accounts for 85% of kidney cancer incidence in the US. Since 1950 there has been a 126% increase in kidney cancer incidence in the US. Thirty percent of new patients present with a localized easily treatable carcinoma while 30% of patients present with a high-grade metastatic carcinoma. Five-year survival rates for metastatic RCC is 6-12 months (Lipworth et al, 2006). Current disease treatment options for metastasis include chemotherapy and radiation (8% response rate), immunotherapy (15-30% response rate) and newly developed angiogenesis inhibitors which are in phase III trials (Staehler et el, 2005). In RCC cells, it has been shown that PPAR? agonists inhibit cell proliferation, induce apoptosis, and induce anti-angiogenic effects in vitro. Unlike most tumor types, PPAR? is downregulated in tissue samples from 47 RCC patients. However, in cell culture studies PPAR? expression does not correlate with growth inhibitory or apoptotic effects of PPAR? agonists in renal cell lines indicating that PPAR? independent responses may play a large role in actions associated with the PPAR? agonists (Yuan et al, 2006). 1,1-Bis(3'-indolyl)-1-(p-substitutedphenyl)methanes containing p-trifluoromethyl, p-t-butyl and p-phenyl substituents activate peroxisome proliferator-activated receptor (PPAR) and inhibit growth of ACHN and 786-0 renal cell carcinoma cell lines. PPAR is overexpressed in ACHN cells and barely detectable in 786-0 cells, and treatment with the t-butyl analog (DIM-C-pPhtBu) induces cell cyle inhibition. DIM-C-pPhtBu also induced several common PPAR-independent proapoptotic responses in ACHN and 786-0 cells, including increased expression of nonsteroidal antiimflammatory drug-activated gene-1 (NAG-1) and endoplasmic reticulum stress which activates death receptor 5 and the extrinsic pathway of apoptosis. In addition, DIM-C-pPhtbu (40 mg/kg/d) also inhibited tumor growth in an orthotopic mouse model for renal carcinogenesis, and this was accompanied by induction of apoptosis in renal tumors treated with DIM-C-pPhtBu but not in tumors treated with the corn oil vehicle (control). Thus, DIM-C-pPhtBu and related compounds represent a novel class of mechanism-based drugs that have potential for treatment of renal adenocarcinoma for which there are currently limited options for successful chemotherapy.Item 11th Grade Students' English Reading Motivation, Language Problems and Reading Achievement in Taiwan(2012-07-16) Su, Jung-HsuanMotivation has been viewed as a very influential factor to successful reading for English as foreign language learners. Learners can be motivated to read English by extrinsic or intrinsic motivation, and the motivational orientations could also influence their reading achievement. However, language problems that EFL learners encounter while reading can affect their willingness to read as well as their reading achievement. The purpose of this study was to investigate Taiwanese EFL students? English reading motivation and its relationship with perceived language problems and reading achievement. 302 11th grade students from an urban district in southern Taiwan participated in the study. Measures included an English reading comprehension test, an English reading motivation questionnaire, and a questionnaire regarding language problems in reading English. A factor analysis was used to determine the motivational orientations. Multiple regression and correlation analysis were performed to examine the relationship among reading motivation, language problems, and reading achievement. The results showed that: 1) Taiwanese senior high school students were largely motivated to read English by extrinsic motivation, specifically the importance and instrumental utility of reading English and the drive for recognition and competition, although they could also be motivated by intrinsic motivation to read English for knowledge and social purposes. Moreover, extrinsic motivation to read for compliance was significantly associated with their English reading scores. 2) While reading English, unknown idiomatic expressions and vocabulary were frequently reported language problems that influenced students? willingness to read. Nevertheless, lack of grammar knowledge was generally not considered a big language problem to most of the students while reading. 3) Language problems in reading English and reading motivation were correlated, and motivation to read for compliance, grammar knowledge, and overall reading comprehension were significant predictors of students? English reading scores. This study highlights the influential role of extrinsic motivation to EFL students in English reading and the importance of knowledge of vocabulary and idiomatic expressions in order to help understand the meaning of English texts. It provides implications for English teachers in designing appropriate curriculum that suits students? needs and interests, and also suggestions for choosing proper reading materials.Item 142pr glass seeds for the brachytherapy of prostate cancer(Texas A&M University, 2007-09-17) Jung, Jae WonA beta-emitting glass seed was proposed for the brachytherapy treatment of prostate cancer. Criteria for seed design were derived and several beta-emitting nuclides were examined for suitability. 142Pr was selected as the isotope of choice. Seeds 0.08 cm in diameter and 0.9 cm long were manufactured for testing. The seeds were activated in the Texas A&M University research reactor. The activity produced was as expected when considering the meta-stable state and epi-thermal neutron flux. The MCNP5 Monte Carlo code was used to calculate the quantitative dosimetric parameters suggested in the American Association of Physicists in Medicine (AAPM) TG-43/60. The Monte Carlo calculation results were compared with those from a dose point kernel code. The dose profiles agree well with each other. The gamma dose of 142Pr was evaluated. The gamma dose is 0.3 Gy at 1.0 cm with initial activity of 5.95 mCi and is insignificant to other organs. Measurements were performed to assess the 2-dimensional axial dose distributions using Gafchromic radiochromic film. The radiochromic film was calibrated using an X-ray machine calibrated against a National Institute of Standards and Technology (NIST) traceable ion chamber. A calibration curve was derived using a least squares fit of a second order polynomial. The measured dose distribution agrees well with results from the Monte Carlo simulation. The dose was 130.8 Gy at 6 mm from the seed center with initial activity of 5.95 mCi. AAPM TG-43/60 parameters were determined. The reference dose rate for 2 mm and 6 mm were 0.67 and 0.02 cGy/s/mCi, respectively. The geometry function, radial dose function and anisotropy function were generated.Item 16S rRNA-Based Tag Pyrosequencing of Complex Food and Wastewater Environments: Microbial Diversity and Dynamics(2012-02-14) McElhany, KatherineEnvironmental microbiology has traditionally been performed using culture-based methods. However, in the last few decades, the emergence of molecular methods has changed the field considerably. The latest development in this area has been the introduction of next-generation sequencing, including pyrosequencing. These technologies allow the massively parallel sequencing of millions of DNA strands and represent a major development in sequencing technologies. The purpose of this study was to use both pyrosequencing and traditional culture-based techniques to investigate the diversity and dynamics of bacterial populations within milk and untreated sewage sludge samples. Pasteurized and raw milk samples were collected from grocery stores and dairies within Texas. Milk samples were analyzed by plating, pyrosequencing, and an assay for the presence of cell-cell signaling molecules. Samples were processed, stored, and then evaluated again for spoilage microflora. The results of this study showed that raw milk had a considerably higher bacterial load, more diversity between samples, and a significantly higher concentration of pathogens than pasteurized milk. Additionally, this study provided evidence for varying spoilage microflora between raw and pasteurized milk, as well as evidence for the production of cell-cell signaling molecules by bacterial organisms involved in milk spoilage. Four samplings of untreated sewage sludge were collected from wastewater treatment plants in seven different municipalities across the United States. Samples were subjected to quantification of selected bacterial organisms by culture and a pyrosequencing analysis was performed on extracted community DNA. The results of this study showed that untreated sewage sludge is inhabited by a huge diversity of microorganisms and that certain municipalities may have distinct bacterial populations that are conserved over time. Additionally, this study provided some evidence for seasonal differences in several of the major bacterial phyla. Lastly, this study emphasized the challenges of comparing results obtained by culture and pyrosequencing. In conclusion, this study showed that both milk and sewage are highly diverse, dynamic environments that can contain organisms of public health concern. The use of both culture-based methods and pyrosequencing in this study proved a complementary approach, providing a more comprehensive picture of both microbial environments.Item 16th Century Cast-Bronze Ordnance at the Museu de Angra do Heroismo(Texas A&M University, 2004-09-30) Hoskins, Sara GraceWithin the collections of the Museu de Angra do Heroismo (Terceira Island, Azores, Portugal) are nine cast bronze guns from the 16th century. Most were raised from the seafloor between the 1960s and 1990s, but this study comprises the first in-depth research into their design and manufacture. The importance of this kind of study lies in the fact that ordnance is commonly found on shipwrecks of this time. A greater knowledge of guns will help provide information about the ships from which they came. Careful documentation and study of the Museu de Angra cannon will add greatly to their value as museum exhibits, by allowing museum patrons to better understand where the guns came from, how they were cast, and why they were important. This documentation adds to our knowledge of Western European gunfounding technology during the sixteenth century, as four different countries commissioned the guns: Portugal, Spain, France, and England. With detailed documentation and publication, the Museu de Angra bronze guns can be added to the bibliography of ordnance of this period, which will aid future researchers who encounter similar pieces. The Museu de Angra bronze guns, as symbols of the military and naval power of the countries that commissioned them, were sent aboard ships, into the field, and mounted on fortress walls. Bronze guns of this time period are particularly important, as bronze was an expensive commodity, and the demand for ordnance was increasing rapidly. Countries developed more effective ways to make use of iron for the founding of guns, and the use of bronze became more symbolic of wealth. The information that each gun contains includes both the cutting-edge military technology of the time and the artistic statement of the founder. Some of the finest metalwork of the period was displayed in cast bronze guns, and due to the founding techniques, no two are the same, making each an important piece of history.Item 2-Dimensional Seismic Refraction Mapping Study of the Cretaceous-Paleogene Boundary Complex from the Brazos, Texas Section(2012-07-16) Gowan, Joshua SmithMany scientific studies have been conducted on the Cretaceous-Paleogene boundary (KTB) in the Gulf coast region and, in particular, the Brazos River section in Falls County, Texas. Despite this, there remains much to be learned about the KTB and its depositional environment. Study of the KTB has been multidisciplinary, primarily in the fields of sedimentology and paleontology. Some researchers in these disciplines have questioned the consensus view of the placement of the KTB and subsequent interpretation of the timing of depositional events and mass extinction events. Geophysical methods have potential to provide additional understanding of the physical properties of the KTB. To date, study of the KTB has relied on point data and borehole information to create cross sections of the complex. Seismic refraction surveys can provide spatially continuous information on susburface horizons located adjacent to the KTB. In this study, seismic first-arrival traveltimes are processed with a tomographic modeling program to map the top of the hummocky cross-bedded sandstone (HCS), which is a key indicator of the deposition environment at the time of KTB boundary complex placement. The survey area is located at Cottonmouth Creek, a tributary of the Brazos River. Three seismic lines were surveyed, one across Cottonmouth Creek, and two parallel to the creek on either side. The data from the two parallel lines were processed using the 2-D seismic refraction tomography algorithm of Zelt and Smith. The reconstructed depth to the HCS in the survey area is approximately 6 m, with layer seismic velocities of 364, 1800, and 2200 m/s, respectively. Seismic tomography successfully mapped the HCS layer and reveals approximately 1 m amplitude undulations vertically and undulations on the order of several m horizontally. These variations are consistent with exposed surfaces of the HCS in the creek bed. Seismic refraction has been utilized successfully herein to map a key buried indicator, namely the top of the HCS layer, associated with the KTB complex. A detailed 3-D seismic refraction survey at this site is recommended to generate a high-resolution 2-D terrain map of the top of the HCS layer.Item 2008 Midwest Levee Failure: Erosion Studies(2011-02-22) Bernhardt, Michelle LeeThe United States contains an estimated 100,000 miles (160000 km) of levees in which erosion related issues are the top priorities. Proper documentation of overtopping induced erosion is a complicated issue involving the collection and analysis of timesensitive field data and personal observations. This thesis is a study of the performance of the Midwest Levee system during the 2008 flooding events. The goal of the Midwest Levee investigation was to gather and analyze perishable data in an effort to provide a comprehensive overview at each breach location. To predict how a site will perform during a particular flood event, there are three main inputs: the flood conditions, the site conditions, and the soil properties. Site geometry and imperfections can greatly affect the performance of a levee system. Any low spots or potential seepage paths can concentrate the flow and be detrimental to the levee. The vegetative cover is the single most important condition at a site. As seen in the Brevator case, vegetative armor can prevent failure of a levee comprised of less resistant soils subjected to long periods of overtopping. Recommended grasses include: Switchgrass, Smooth Brome, Reed Canarygrass, and Tall Fescue. It is also recommended that grasses are kept at least 0.5 m tall during the flood season and to limit the presence of trees to 10 m beyond the levee toe. The erosion resistance of the materials comprising the levee is also important. From the correlations in this study, it was determined that erodibility is influenced by grain size, relative compaction, clay content, and activity. Devices like the Torvane and Pocket Erodometer can also be used to get a quick field estimate of erosion. While these correlations and field devices give insight into an erodibility value, they are no substitute for site specific analysis with laboratory equipment such as the Erosion Function Apparatus. Soil behavior is highly nonlinear and the entire erosion function is needed to get an accurate measure of the erodibility of a soil. By combining these properties in an erosion matrix, a prediction of whether a site will withstand a given flood event can be made.Item 2011 Corporate Headquarters: An Analysis of Immediate Communities(2013-04-25) Conti, Serena NicoleWhile the Bay Area?s history has shaped today?s culture, there is little written about how corporations affect their immediate communities. This thesis focuses on the largest corporations in the Bay Area to determine if these corporations have any effect on the surrounding communities. The study focuses on Fortune 500?s list of Largest Corporations for 2011, and within that list, the top 30 companies located in the nine Bay Area counties. These nine counties include: Alameda County, Contra Costa County, Marin County, Napa Country, San Francisco County, San Mateo County, Santa Clara County, Solano Country, and Sonoma County. Using each corporations? headquarter address as the reference point, a 1-mile radius surrounding each of the 30 companies was assessed. Data was gathered for the years 2000, 2010, and projected 2015. These data are available via ESRI?s Business Analyst Online application, which is accessible through the Texas A&M University Library?s website. Demographic information such as population, income, education, and related characteristics were reviewed. To understand the population?s lifestyle and possible implications for real estate development opportunities, the study reviewed the local demographic spending patterns, what these people do for recreation, their occupations, whether they rent or own their home, how they travel to work and their commute times, and other lifestyle variables. There were 40 variables tested and 53-percent of those variables produced statistically significant results. While the Demographic variable yielded a 56-percent statistical significance rate and the Consumer Spending variable yielded a 43-percent statistical significance rate, the Business variable did not produce any statistical significance. The most significant variables drawn from the reports were Demographics and Income Comparison, House and Home Expenditures, and Recreation Expenditures. This analysis provides important information regarding whether there is a statistical significance between characteristics within these companies? 1-mile radii and the overall MSA. In the future, if a company would like to expand and build another headquarters, this analysis may provide insight on what metrics to focus on for future development. There may also be important information for future development opportunities around these 30-companies.Item 3-D Electrical Resistivity Tomography for Cliff Stability Assessment at Pointe du Hoc in Normandy, France(2010-01-14) Udphuay, SuwimonPointe du Hoc overlooking the English Channel in Normandy, France was host to one of the most important military engagements of World War II. While the site is a valuable historic cultural resource, it is vulnerable to cliff collapses that already have endangered the observation post and Rudder?s command post. The observation post has been closed to visitors for some time due to safety concerns. Geophysical techniques have been used increasingly in recent years for slope stability investigation purposes. The objective of this study is to apply advanced 3?D resistivity tomography toward a detailed site stability assessment with special attention to the two at-risk buildings. 3?D resistivity tomography datasets at Pointe du Hoc in the presence of extreme topography and dense cultural clutter have been successfully acquired, inverted, and interpreted. The cliff stability in the areas around the two at?risk buildings has been analyzed. A hazard assessment scheme has been designed in which regions of high resistivity are interpreted as zones of open, dry fractures with a moderate mass movement potential. Regions of low resistivity are zones of wet, clay?filled fractures with a high mass movement potential. The observation post tomography results indicate that the highest mass movement hazard appears to be associated with the marine caverns at the base of the cliff that are positioned at the point of strongest wave attack. These caverns likely occupy the future site of development of a sea arch which will definitely threaten the observation post building. A high probability of a soil wedge failure is on the east?facing cliff edge close to the observation post that could damage or destroy the building. The mass movement potential at the Rudder?s command post area is low to moderate. The greatest risk is associated with soil wedge failures at the top of the cliffs. The resistivity geophysical data add great value to the natural geohazard assessment at Pointe du Hoc and constitute an integral component of an interdisciplinary approach to the problem of cultural resource preservation at the site. Geophysics is a non?invasive and relatively inexpensive technology that provides unique constraints which are unobtainable using traditional engineering geology methods for site characterization. However, the technology is difficult to master and the inherent limitations must be carefully understood to ensure a reliable geotechnical interpretation.Item 3-D multichannel seismic reflection study of variable-flux hydrocarbon seeps, continental slope, northern Gulf of Mexico(Texas A&M University, 2004-11-15) Thomas, Ryan DouglasIn the northern Gulf of Mexico, seafloor hydrocarbon fluid and gas seepage is an ubiquitous process on the continental margin. Although seafloor seepage and seep-related features (mud volcanoes, carbonate formation) have been studied for many years, little is known about their mechanisms of formation and the relationship of sub-surface structure to current seep activity. In this study, we examined three seafloor seeps in the Garden Banks and Mississippi Canyon areas using exploration and reprocessed 3D multi-channel seismic (MCS) data augmented with side-scan sonar (Garden Banks site) to characterize hydrocarbon seep activity and develop an understanding of the processes that led to their formation. Side-scan sonar data provided high resolution coverage of the seafloor while the exploration seismic data were used to image near and deep sub-surface features. Additionally, the 3D amplitude extraction maps were useful in delineating amplitude anomalies often associated with seep related activity. The reprocessed 3D seismic data were used to map in greater detail near seafloor features and amplitude anomalies. Using remote sensing geophysical data, we were effectively able to map sub-surface features such as salt topography, seep-related faults and geophysical indicators of hydrocarbons and correlate them with seafloor amplitude anomalies and fault traces in order to characterize seep activity level. The southern mud volcano in the Garden Banks site is characterized as an established high flux seep vent owing to signs of active seepage and sediment flows as well as the build-up of hard grounds. The northern mud volcano in the area, with greater hard ground build-up and fewer signs of active seepage represents an established low flux seep vent. In the Mississippi Canyon area, the data suggest that the seep mound can be characterized as a mature high flux vent due to the extensive build-up of hard ground, evidence of gas hydrates and signs of active seepage and sediment flows. The mechanisms of formation are similar between the two study sites. Upwelling salt appears to have fractured the sub-surface leading to the formation of fault induced depressions. Mapping of geophysical indicators of hydrocarbons implies that hydrocarbon migration is occurring along bedding planes to the fault systems underlying the depressions. Here they appear to migrate vertically to the seafloor creating the topographic features and seafloor amplitude anomalies that characterize the seepsItem 3-D structural and seismic stratigraphic interpretation of the Guasare-Misoa Interval, VLE 196 Area, Block V, Lamar Field, Lake Maracaibo, Venezuela(Texas A&M University, 2004-09-30) Arzuman, SadunIn this study, the structure, depositional system, and the seismic stratigraphy of the VLE 196 area, Block V in Lamar Field were interpreted using 3-D seismic data and well logs to characterize structural and depositional settings of the Guasare-Misoa interval. To demonstrate structural settings of the study area 3-D seismic data were interpreted. Three main seismic reflectors, which are the Late Eocene unconformity, Guasare, and La Luna formations, were picked. The most dominant structure in the area is the VLE 400 Fault which was interpreted as a left-lateral strike-slip reverse fault due to its behaviors as a reverse fault in cross sections and as a strike-slip fault in strike sections. The VLE 400 Fault subdivides the VLE 196 area into two main structural blocks, a downthrown block in the western part and the upthrown block in the eastern part of the field where the hydrocarbons were trapped. Several en echelon normal and reverse faults were located along the both sides of the area. The main importance of these faults are that they fractured the La Luna source rock and created migration pathways through the reservoir layers of the Misoa Formation. To interpret depositional system of the Guasare-Misoa interval, tops of the C4 and C5 intervals and associated C4 layers were picked based on well logs and lithofacies maps were prepared. The results of this part of the study show that the sandstones of the Misoa Formation are delta front and fluvial/distributary channel facies of delta system. The net sand thickness map of the C4 interval also exhibits southeast northwest contour patterns reflecting depositional axes in the area. Shaly units of the C4 interval interpreted as potential seals and are of variable thickness and extend. Seismic stratigraphic interpretation of the area shows that the four main seismic facies are dominant which mainly represent the recent sediments, "C" sands of the Misoa Formation, underlying Colon and Mito Juan shales, and basement respectively. Some distributary eroded channel fill structures were also observed within the Misoa Formation, but they were not continuous through the area because of the intensive faulting.Item 38-kHz ADCP investigation of deep scattering layers in sperm whale habitat in the northern Gulf of Mexico(Texas A&M University, 2005-02-17) Kaltenberg, Amanda MayA hull-mounted 38-kHz phased-array acoustic Doppler current profiler (ADCP) was used to acoustically survey the continental margin of the northern Gulf of Mexico (GOM) during 6 cruises in 2002-2003. This is the first backscatter survey with a 38-kHz ADCP in the Gulf of Mexico. ADCPs have been used as a proxy to measure the volume backscatter return from plankton in the water column, however previous studies were restricted to the upper 200 to 300 meters due to the relatively high frequency of operation (150-300 kHz) of the transducers. In addition to measuring deep water current velocities, the 38-kHz phased-array ADCP can measure Relative Acoustic Backscatter Intensity (RABI) as deep as 1000 meters. The daytime depth of the main deep scattering layer at 400 to 500 meters was resolved, and locally high backscatter intensity can be seen down to 800 meters. The objectives were to determine how to analyze RABI from the instrument to resolve scattering layers, and then to seek secondary deep scattering layers of potential prey species below the main deep scattering layer, from 600 to 800 meters in the feeding range for Gulf of Mexico sperm whales. Based on RABI from the 38-kHz ADCP, secondary DSLs in sperm whale diving range were more commonly recorded over the continental shelf than in the deep basin region of the Gulf of Mexico. The daytime depths of migrating plankton showed variation depending on physical circulation features (cyclone, anticyclone, proximity to Mississippi river, and Loop Current) present. Vertical migrations compared between concurrently running 38 and 153-kHz ADCPs showed an overlap of acoustic scatterers recorded by the two instruments, however the 153-kHz instrument has much finer vertical resolution. Vertical migration rates were calculated and simultaneous net tow samples from one of the cruises was used to compare abundance estimates by the two methods.Item 3D characterization of acidized fracture surfaces(Texas A&M University, 2007-09-17) Malagon Nieto, CamiloThe complex interrelations among the different physical processes involved in acid fracturing make it difficult to design, and later, to predict the outcome of stimulation jobs. Actual tendencies require the use of computational models to deal with the dynamic interaction of variables. This thesis presents a new study of acidized surface textures by means of a laser profilometer to improve our understanding of the remaining etched surface topography and its hydraulic response. Visualization plots generated by the profilometer identified hydrodynamic channels that could not be identified by the naked eye in acidized surfaces. The plots clarified the existence of rock heterogeneities and revealed how the processes of dissolution function in chalk rock. Experimental data showed clearly that the effect of dissolution depends on the type of rock and the fluid system; dolomite, for example, dissolves more rapidly but more roughly than limestone. Fluid leakoff rate and temperature also affect the dissolution. Further research is necessary to clarify the effects of conductivity.Item 3D engine for immersive virtual environments(Texas A&M University, 2005-02-17) Anderson, Christopher DeanThe purpose of this project is to develop a software framework, a 3D engine, which will generate images to be projected onto facets of a spatially immersive display (SID). The goal is to develop a software library to support the creation of images of specified 3D environments which are specific to the display geometries of a polyhedral class of SIDs. Part of this goal is developing auxiliary software to allow this library to be thoroughly tested. When properly working, the images being displayed on adjoining faces of the SID appear spatially and temporally consistent with one another, creating the illusion that the user is within a surrounding three-dimensional space.Item 3D face recognition with wireless transportation(2009-05-15) Zou, LeIn this dissertation, we focus on two related parts of a 3D face recognition system with wireless transportation. In the ?rst part, the core components of the system, namely, the feature extraction and classi?cation component, are introduced. In the feature extraction component, range images are taken as inputs and processed in order to extract features. The classi?cation component uses the extracted features as inputs and makes classi?cation decisions based on trained classi?ers. In the second part, we consider the wireless transportation problem of range images, which are captured by scattered sensor nodes from target objects and are forwarded to the core components (i.e., feature extraction and classi?cation components) of the face recognition system. Contrary to the conventional de?nition of being a transducer, a sensor node can be a person, a vehicle, etc. The wireless transportation component not only brings ?exibility to the system but also makes the ?proactive? face recognition possible. For the feature extraction component, we ?rst introduce the 3D Morphable Model. Then a 3D feature extraction algorithm based on the 3D Morphable Model is presented. The algorithm is insensitive to facial expression. Experimental results show that it can accurately extract features. Following that, we discuss the generic face warping algorithm that can quickly extract features with high accuracy. The proposed algorithm is robust to holes, facial expressions and hair. Furthermore, our experimental results show that the generated features can highly di?erentiate facial images. For the classi?cation component, a classi?er based on Mahalanobis distance is introduced. Based on the classi?er, recognition performances of the extracted features are given. The classi?cation results demonstrate the advantage of the features from the generic face warping algorithm. For the wireless transportation of the captured images, we consider the location-based wireless sensor networks (WSN). In order to achieve e?cient routing perfor?mance, a set of distributed stateless routing protocols (PAGER) are proposed for wireless sensor networks. The loop-free and delivery-guaranty properties of the static version (PAGER-S) are proved. Then the performance of PAGER protocols are compared with other well-known routing schemes using network simulator 2 (NS2). Simulation results demonstrate the advantages of PAGER.Item 3D Facial Performance Capture From A Single RGBD Camera(2013-05-28) Chen, Yen-LinRealistic facial animation remains one of the most challenging problems in computer graphics, where facial performance capture of real people has been a key component. The current state-of-the-art technologies used to capture facial performances are far too expensive and cumbersome for general users, which limits the potential applications of performance capture. The primary contribution of this dissertation is to propose two systems that are suitable for common users to capture facial performance using a single low-cost device. Our first system focuses on large-scale facial performance reconstruction from a single RGBD image. Our goal is to accurately reconstruct global transformation, as well as large-scale deformations from the images provided by a single shot of a Microsoft Kinect camera. With the combination of a robust facial feature detector and an image-based registration method, our system is automatic, robust and accurate to reconstruct facial movements. The result face meshes are topology consistent and with dense correspondences. Since people are natural experts of native human expressions and can distinguish subtle differences, e.g. dynamic facial wrinkles, we propose a second system combining our performance capture with a 3D scanning system to add person-specific high-resolution details in an efficient and effective way. We demonstrate the power of our proposed systems by testing on both real and synthetic data, as well as a commercially available motion capture system. Results show that the proposed systems generate believable and comparable results. We believe the proposed systems should be useful and applicable for general as well as professional users.Item 3D interactive pictorial maps(Texas A&M University, 2005-02-17) Naz, AsmaThe objective of my research is to revive and practice the art of traditional pictorial maps in 3D cartographic visualization. I have chosen to create both graphical and statistical pictorial maps which can be used for the purpose of tourism and data representation respectively. Some traditional hand-drawn and sculptural pictorial maps of famous artists have been picked out to start as a base for my work. The goal was to recreate or imitate the style, character and features of these traditional hand-drawn and sculptural maps with 3D computer graphics and to analyze how effectively 3D tools can be used to communicate map information. I also wanted to explore ways to make these maps interactive on the Web and have them accessible to a large number of viewers. The results show a number of interactive 3D pictorial maps of different countries and continents. These maps are initially built with Maya, a 3D modeling software, and converted into web pages using the Viewpoint Technology. For statistical maps, Mel scripts have been used in Maya to take input from the user and change the shape of models accordingly to represent data. These maps are interactive and navigable and are designed to be easily accessible on the Web.Item 3D Maneuvers For Asymmetric Under-Actuated Rigid Body(2013-08-01) Kim, Dong HoonMost spacecraft are designed to be maneuvered to achieve pointing goals. This is generally accomplished by designing a three-axis control system. This work explores new maneuver strategies when only two control inputs are available: (i) sequential single-axis maneuvers and (ii) three-dimensional (3D) coupled maneuvers. The sequential single-axis maneuver strategies are established for torque, time, and fuel minimization applications. The resulting control laws are more complicated than the equivalent results for three-axis control because of the highly nonlinear control switch-times. Classical control approaches lead to optimal, but discontinuous control profiles. This problem is overcome by introducing a torque-rate penalty for the torque minimization case. Alternative approaches are also considered for achieving smooth continuous control profiles by introducing a cubic polynomial multiplicative control switch smoother for the time and fuel minimization cases. Numerical and analytical results are presented to compare optimal maneuver strategies for both nominal and failed actuator cases. The 3D maneuver strategy introduces a homotopy algorithm to achieve optimal nonlinear maneuvers minimizing the torque. Two cases are considered: (i) one of the three-axis control actuators fails and (ii) two control actuators fail among four control actuators. The solution strategy first solves the case when all three actuators are available. Then, the failed actuator case is recovered by introducing a homotopy embedding parameter, ?, into the nonlinear dynamics equation. By sweeping ?, a sequence of neighboring optimal control problems is solved that starts with the original maneuver problem and arrives at the solution for the under-actuated case. As ? approaches 1, the designated actuator no longer provides control inputs to the spacecraft, effectively modeling the failed actuator condition. This problem is complex for two reasons: (i) the governing equations are nonlinear and (ii) ? fundamentally alters the spacecraft?s controllability. Davidenko?s method is introduced for developing an ordinary differential equation for the costate variable as a function of ?. For each value of ?, the costate initial conditions are iteratively adjusted so that the terminal boundary conditions for the 3D maneuver are achieved. Optimal control applications are presented for both rest-to-rest and motion-to-rest cases that demonstrate the effectiveness of the proposed algorithm.Item 3D Modeling of Coupled Rock Deformation and Thermo-Poro-Mechanical Processes in Fractures(2012-07-16) Rawal, ChakraProblems involving coupled thermo-poro-chemo-mechanical processes are of great importance in geothermal and petroleum reservoir systems. In particular, economic power production from enhanced geothermal systems, effective water-flooding of petroleum reservoirs, and stimulation of gas shale reservoirs are significantly influenced by coupled processes. During such procedures, stress state in the reservoir is changed due to variation in pore fluid pressure and temperature. This can cause deformation and failure of weak planes of the formation with creation of new fractures, which impacts reservoir response. Incorporation of geomechanical factor into engineering analyses using fully coupled geomechanics-reservoir flow modeling exhibits computational challenges and numerical difficulties. In this study, we develop and apply efficient numerical models to solve 3D injection/extraction geomechanics problems formulated within the framework of thermo-poro-mechanical theory with reactive flow. The models rely on combining Displacement Discontinuity (DD) Boundary Element Method (BEM) and Finite Element Method (FEM) to solve the governing equations of thermo-poro-mechanical processes involving fracture/reservoir matrix. The integration of BEM and FEM is accomplished through direct and iterative procedures. In each case, the numerical algorithms are tested against a series of analytical solutions. 3D study of fluid injection and extraction into the geothermal reservoir illustrates that thermo-poro-mechanical processes change fracture aperture (fracture conductivity) significantly and influence the fluid flow. Simulations that consider joint stiffness heterogeneity show development of non-uniform flow paths within the crack. Undersaturated fluid injection causes large silica mass dissolution and increases fracture aperture while supersaturated fluid causes mineral precipitation and closes fracture aperture. Results show that for common reservoir and injection conditions, the impact of fully developed thermoelastic effect on fracture aperture tend to be greater compare to that of poroelastic effect. Poroelastic study of hydraulic fracturing demonstrates that large pore pressure increase especially during multiple hydraulic fracture creation causes effective tensile stress at the fracture surface and shear failure around the main fracture. Finally, a hybrid BEFEM model is developed to analyze stress redistribution in the overburden and within the reservoir during fluid injection and production. Numerical results show that fluid injection leads to reservoir dilation and induces vertical deformation, particularly near the injection well. However, fluid withdrawal causes reservoir to compact. The Mandel-Cryer effect is also successfully captured in numerical simulations, i.e., pore pressure increase/decrease is non-monotonic with a short time values that are above/below the background pore pressure.Item 3D Multi-Field Multi-Scale Features From Range Data In Spacecraft Proximity Operations(2012-07-16) Flewelling, Brien RoyA fundamental problem in spacecraft proximity operations is the determination of the 6 degree of freedom relative navigation solution between the observer reference frame and a reference frame tied to a proximal body. For the most unconstrained case, the proximal body may be uncontrolled, and the observer spacecraft has no a priori information on the body. A spacecraft in this scenario must simultaneously map the generally poorly known body being observed, and safely navigate relative to it. Simultaneous localization and mapping(SLAM)is a difficult problem which has been the focus of research in recent years. The most promising approaches extract local features in 2D or 3D measurements and track them in subsequent observations by means of matching a descriptor. These methods exist for both active sensors such as Light Detection and Ranging(LIDAR) or laser RADAR(LADAR), and passive sensors such as CCD and CMOS camera systems. This dissertation presents a method for fusing time of flight(ToF) range data inherent to scanning LIDAR systems with the passive light field measurements of optical systems, extracting features which exploit information from each sensor, and solving the unique SLAM problem inherent to spacecraft proximity operations. Scale Space analysis is extended to unstructured 3D point clouds by means of an approximation to the Laplace Beltrami operator which computes the scale space on a manifold embedded in 3D object space using Gaussian convolutions based on a geodesic distance weighting. The construction of the scale space is shown to be equivalent to both the application of the diffusion equation to the surface data, as well as the surface evolution process which results from mean curvature flow. Geometric features are localized in regions of high spatial curvature or large diffusion displacements at multiple scales. The extracted interest points are associated with a local multi-field descriptor constructed from measured data in the object space. Defining features in object space instead of image space is shown to bean important step making the simultaneous consideration of co-registered texture and the associated geometry possible. These descriptors known as Multi-Field Diffusion Flow Signatures encode the shape, and multi-texture information of local neighborhoods in textured range data. Multi-Field Diffusion Flow Signatures display utility in difficult space scenarios including high contrast and saturating lighting conditions, bland and repeating textures, as well as non-Lambertian surfaces. The effectiveness and utility of Multi-Field Multi-Scale(MFMS) Features described by Multi-Field Diffusion Flow Signatures is evaluated using real data from proximity operation experiments performed at the Land Air and Space Robotics(LASR) Laboratory at Texas A&M University.