University of Texas at Austin
Permanent URI for this collectionhttps://hdl.handle.net/2249.1/29224
Welcome to The University of Texas at Austin, the largest institution of The University of Texas System. The University of Texas at Austin is a major research university home to more than 48,000 students, 2,700 faculty and 17,000 staff members. This collection contains the theses and dissertations produced at the University of Texas.
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Item 1,000 miles : bridging the distance between Austin and Chicago(2013-05) Hinderaker, Andrew Dean; Dietz, Steven; Lynn, Kirk; Zeder, Suzan1,000 miles marks the culmination of my course of study at the University of Texas. As an MFA student in the playwriting program, I have juggled my responsibilities to the department with my role as a professional playwright, frequently splitting time between Austin and my hometown of Chicago, where I opened four world premieres from 2010-2012. In this thesis, I discuss the ways in which my work has been influenced by the aesthetics of both artistic communities. I focus on two of my plays in particular: Kingsville, which premiered in Chicago during my first semester at UT, and Colossal, which opened in Austin just weeks before graduation. Through the lens of these two plays, I outline my artistic evolution over the past three years, highlighting the ways in which my work has drawn from the very best of Chicago’s storefront theaters and Austin’s experimental scene.Item 1,400 years of biomass burning, climate variability, and environmental change on Ometepe Island, Lake Nicaragua(2007-05) Avnery, Shiri; Dull, RobertThis study examines the relationship between short-term climate variability, paleo-fires, and anthropogenic sources of environmental change over the past 1,400 years on Ometepe Island, located in the tropical dry forests of southwestern Nicaragua. Macroscopic charcoal, loss on ignition, and magnetic susceptibility records were reconstructed from a lake sediment core, and statistical wavelet analyses were performed to contextualize natural fire regimes in this under-investigated tropical biome. Results from this project suggest that fire regimes on Ometepe Island respond to high frequency (sub-centennial scale) climate variations potentially due to the 11- and 22-year sunspot cycles and/or the El Niño Southern Oscillation, with dominant periodicities of ~7, 14, and 24 years. Results additionally support regional paleoenvironmental analyses by providing evidence of anthropogenic environmental impacts between ~600 and 1500 A.D. with a drastic decline after European contact, as well as evidence of widespread drought conditions between 800 - 1000 A.D. and 1150 – 1300 A.D.Item A 1,500-year record of late Holocene temperature variability and recent warming from Laguna Chingaza, Colombia(2012-08) Bixler, Curtis William; Shanahan, Timothy M.Rapid tropical glacier retreat over the last 50 years has been well documented, and has received significant media attention. Many studies suggest these changes are due to rising global surface air temperatures, however disentangling the effects of temperature and precipitation has hampered scientific consensus. Furthermore, because of the shortness of the instrumental record, it is difficult to assess the larger significance of the climate changes associated with the decline of tropical glaciers. Here, we present a locally calibrated, independent temperature reconstruction for the past 1,500 years from Laguna Chingaza, Colombia based on distributions of branched Glycerol Dialkyl Glycerol Tetraethers (brGDGTs) in order to assess the controls on long term temperature variability in the tropical Andes, and their relationship with growth and demise of Andean glaciers. Comparison of reconstructed temperatures with the instrumental record suggests that our proxy record faithfully records decadal to century scale trends in temperature. The largest temperature decline over the last 1,500 years was a decrease of 2.5 ± 0.3 °C during the Little Ice Age (LIA), reaching lowest temperatures during the mid-17th century, and is broadly consistent with terrestrial temperature reconstructions throughout the tropics and the higher latitudes. The structure and timing of temperature changes at Laguna Chingaza are remarkably similar to recent terrestrial temperature reconstructions from elsewhere in the tropics, including sites in the tropical Pacific and equatorial Africa, suggesting that these changes are widespread in the tropics. Together, these records suggest that warming over the last few decades is unprecedented over the last 1,500 years, including the Medieval Climate Anomaly (800-1150 AD). Comparison of these temperature changes with records of Andean glacier limits suggests that temperature is the dominant driver of glacial retreat, particularly over the past few decades. Additionally, paleotemperatures inferred from LIA and recent glacial equilibrium line altitudes (ELAs) underestimate past changes in temperature when compared with brGDGTs reconstructions, suggesting that changes in precipitation complicate the use of glacier ELAs to reconstruct past temperatures. The coupling of temperature and ice extent in South America suggests that with projected future warming, the health of tropical glaciers could be in jeopardy, significantly impacting the communities and ecosystems that depend on them.Item 1-800 worlds : embodiment and experience in the Indian call center economy(2010-08) Krishnamurthy, Mathangi Kasi; Hartigan, John, 1964-; Visweswaran, Kamala; Brow, James; Stewart, Kathleen; Abraham, Itty; Flores, RichardThis dissertation is concerned with the everyday lives of transnational Indian call center workers when situated within the global politics of voice-based outsourcing. The call center economy gained impetus in early 2000-2001, when multinational corporations began to train young men and women in India to mask their spatial and temporal location, in order that they could serve customers in the US and the UK. Taking calls through the night to serve the work day of Western consumers, these customer service agents were asked to assume a different name, location, and cultural and language markers, as part of the requirements of work. I explore the ways in which these young, middle-class workers located themselves within practices, contentious representations, and material outcomes of this transnational outsourcing economy. Through ethnographic research in Pune, a prominent university town and call center hub in western India, I investigate (1) everyday life in and out of the call center, (2) labor management practices within call centers, and (3) the socio-economic and cultural transformations that accompanied and framed the development of the urban Indian call center economy. This research engages with the machinations of multinational corporations as they incorporate large number of labor forces worldwide into transnational work. It builds on three main bodies of theory - flexible or late capital and flexibility, the South Asian postcolonial nation-state, and affective labor. Through these, I provide a thick description of the history, construction, maintenance and disruption of this site, as also the ways in which this particular story of capital was stabilized. I engage with questions such as, what complex negotiations underlie the ostensible success of new service economies in India? What are its cultural, political and economic determinants and ramifications? What grounds are the claims of state, capital and culture being contested or reified upon, and what do such negotiations mean for service workers within the landscape of urban India? This dissertation shows how the practice of everyday life in this transnational milieu is best explained as the collusion and tension between the contested socio-economic spaces of the new Indian middle-classes and middle-class-ness, and an ungrounded discourse of mobile and flexible capital. The stories of call center workers in this analysis are the stories of particular subjects called upon and striving to be constantly flexible in order to successfully become middle-class and global in the same breath, one often seamlessly overlapping the other.Item The (112) surface of group-IV semiconductors and properties of PtSi : a first principle study(2007-08) Bentmann, Hendrik; Demkov, Alexander A.First principle calculations on the (112) surface of the group-IV elements diamond, silicon, germanium and α-tin were carried out within the framework of Density Functional Theory (DFT). We report chemical trends in surface energies, reconstructions and work functions. In addition we investigate two models for the 7x1 indium induced reconstruction of the silicon (112) surface by means of adsorption energies and STM simulations. We find a substitutional model to be favorable compared to on-terrace adsorption in good agreement with LEED and STM experiments. A drop of 0.46 eV in the work function due to the adsorption is found. Furthermore, we investigate the electrical and optical properties of the two room temperature stable silicide phases PtSi and Pt2Si. Experimental data on optical constants is provided and found to be in good qualitative agreement with the theory. Among various orientations the (121) surface of PtSi has the lowest calculated surface energy. This orientation also produces the distinctively highest peak in an X-ray spectrum of a 300 Å film of PtSi. We demonstrate theoretically that PtSi surfaces can perform reconstructions with similar energy gains as known for semiconductor surfaces.Item A 12-bit, 10 Msps two stage SAR-based pipeline ADC(2012-12) Gandara, Miguel Francisco; Sun, Nan; Gharpurey, RanjitThe market for battery powered communications devices has grown significantly in recent years. These devices require a large number of analog to digital converters (ADCs) to transform wireless and other physical data into the digital signals required for digital signal processing elements and micro-processors. For these applications, power efficiency and accuracy are of the utmost importance. Successive approximation register (SAR) ADCs are frequently used in power constrained applications, but their main limitation is their low sampling rate. In this work, a two stage pipelined ADC is presented that attempts to mitigate some of the sampling rate limitations of a SAR while maintaining its power and resolution advantages. Special techniques are used to reduce the overall sampling capacitance required in both SAR stages and to increase the linearity of the multiplying digital to analog converter (MDAC) output. The SAR sampling network, control logic, and MDAC blocks are completely implemented. Ideal components were used for the clocking, comparators, and switches. At the end of this design, a figure of merit of 51 fJ/conversion-step was achieved.Item 14 MeV neutron generator dose modeling(2013-12) McConnell, Kristen Alycia; Biegalski, Steven R.Modeling and understanding the doses around the neutron generator provides insightful data in regard to radiation safety and protection precautions. Published data can be used to predict doses, but realistic data for the Nuclear Engineering Teaching Laboratory’s Thermo MP 320 Neutron Generator helps health physicists more accurately predict dose rates and protect experimenters against exposure. The goal was to create a model inclusive of the entire setup and room where the neutron generator is housed. Monte Carlo N-Particle (MCNP) Code reigns as the preferred method for modeling radiation transport and was utilized to model the transport of neutrons within the current configuration of the 14 MeV neutron generator facility. This model took into account all shielding materials and their respective dimensions and locations within the concrete room. By utilizing tallies and tally modifiers, the model predicts dose rates that can be used with experimental factors such as irradiation time and flux to predict a dose in millirem. Validation experiments were performed in the current setup using Landauer Luxel®+ with Neutrak dosimeters placed in strategic locations to record the neutron dose vi received as well as a Ludlum Model 42-41 PRESCILA neutron probe to predict dose rates. The dosimeters and PRESCILA measurement locations matched the positions of the point detector tallies in MCNP. After laboratory analysis, a comparison was performed between the model output and the dosimeter and PRESCILA values to successfully validate the accuracy of the model.Item The 1941 Junior League docent training course conducted by the Metropolitan Museum of Art : an examination of museum education beliefs and convictions towards volunteer educators(2011-05) Roath, Elizabeth Grace Margaret; Bolin, Paul Erik, 1954-; Mayer, Melinda M.This thesis explored the 1941 docent-training course for members of the Junior League held at the Metropolitan Museum of Art. The research focused on understanding what place this philanthropic organization held in the American art museum at that time. This course at the Metropolitan Museum of Art was formed as an attempt to teach Junior League members to become trainers of docents and volunteers in their own communities. Additionally, I looked into the background of the museum staff members Francis Henry Taylor and Roberta Murray Fansler Alford Capers and the Junior League member Helen T. Findlay. Utilizing historical research methods, four augments were formed regarding why this docent-training course occurred; (a) the new leadership and structure in the museum facilitating those training, (b) the collaborative work of Helen T. Findlay and Francis Henry Taylor and their passion towards art education for all audiences, (c) the Junior League’s continued commitment to community involvement, and (d) the fundamental need women had for involvement outside the home. The research concludes with a reflection toward the difficulties and hardships that accompany conducting historical research into the women of art education including non-traditional forms of historical documentation.Item 19th century plantation counter-discourses in Juan Francisco Manzano, Gabriel de la Concepción Valdés (Plácido), and Eleuterio Derkes(2010-12) Oleen, Garrett Alan; Arroyo-Martínez, Jossianna; Salgado, César Augusto; Nicolopolus, James R.; Harney, Michael P.; Sidbury, James; Bernucci, LeopoldoMy purpose in writing this dissertation is to re-evaluate the works of three influential Spanish-Caribbean authors who seem to be remembered more as exceptional historical characters rather than for their literature itself. Although often considered to be important contributors to the Spanish-Caribbean literary canon, these writers have also suffered a measure of marginalization as scholars have relegated them to the status of discursive subjects rather than evaluate them as authorial agents. As a consequence, the majority of their works have not been fully recognized as important factors in nineteenth, twentieth, and twenty first century literary production. I show how in their writings – many of which have been misunderstood, under-evaluated, and/or forgotten altogether – these writers narrated their own precarious situations and lifted their voice in protest against slavery, racism and economic oppression at a time when the dominant discourses and heavy-handed controls of the Spanish colonial government strictly forbid them to do so. These authors are Juan Francisco Manzano, Gabriel de la Concepción Valdés (Plácido) and Eleuterio Derkes. Because these authors lived in Cuba (Manzano and Plácido) and Puerto Rico (Derkes) as colonial subjects underneath the oppressive structures of their respective plantation and hacienda economies based on sugar production and slave labor, they experienced difficult colonial conditions and as such are able to narrate this life through a unique perspective that other writers associated with the dominant discourses of the time could not. While these brands of hegemony were indeed forced upon them as writers and artists, it did not stop them from narrating and communicating their unique Spanish Caribbean perspective. I show how these authors, as marginalized figures of nineteenth century plantation society, engineered their own discourses around these hegemonic institutions – writing between the lines of hegemony and concurrent with it at the same time – in order to create an alternative image of nineteenth century Spanish Caribbean society that requires further critical consideration and perspective.Item 2-D magnetic equilibrium and transport modeling of the X-divertor and super X-divertor for scrape-off layer heat flux mitigation in tokamaks(2014-08) Covele, Brent Michael; Mahajan, Swadesh M.; Gentle, Kenneth W.Intense heat fluxes from the divertor incident on material surfaces represent a “bottleneck” problem for the next generation of tokamaks. Advanced divertors, such as the X-Divertor (XD) and Super X-Divertor (SXD), offer a magnetic solution to the heat flux problem by (a) increasing the plasma-wetted area via flux expansion at the targets, and (b) possibly opening regimes of stable, detached operation of the divertor via flux tube flaring, as quantified by the Divertor Index. The benefits of the XD and SXD are derived from their unique magnetic geometries, foregoing the need for excessive gas puffing or impurity injection to mitigate divertor heat fluxes. Using the CORSICA magnetic equilibrium code, XDs and SXDs appear feasible on current- and next-generation tokamaks, with no required changes to the tokamak hardware, and respecting coil conductor limits. Divertor heat and particle transport modeling is performed in SOLPS 5.1 for XD or SXD designs in NSTX-Upgrade, Alcator C-Mod, and CFNS/FNSF. Incident heat fluxes at the targets are kept well below 10 MW/m², even for narrow SOL widths in high-power scenarios. In C-Mod and CFNS, parallel temperature profiles imply the arrestment of the detachment front near the targets. Finally, an X-Divertor for ITER is presented.Item The 2.7 Å resolution structure of the catalytic domain of the dihydrolipoamide succinyltransferase from Escherichia coli in complex with coenzyme A and the 1.45 Å resolution structure of murine macrophage migration inhibitory factor in complex with phenylacetylenepyruvate(2005) Golubkov, Pavel Aleksandrovich; Hackert, Marvin L.Item A 20-coil array system for high-throughput dynamic contrast-enhanced mouse MRI(2011-12) Ramirez, Marc Stephen; Bankson, James A.; Hazle, John D.MRI is a versatile tool for systematically assessing anatomical and functional changes in small animal models of human disease. Its noninvasive nature makes MRI an ideal candidate for longitudinal evaluation of disease progression in mice; however achieving the desired level of statistical power can be expensive in terms of imaging time. This is particularly true for cancer studies, where dynamic contrast-enhanced (DCE-) MRI, which involves the repeated acquisition of anatomical images before, during, and after the injection of a paramagnetic contrast agent, is used to monitor changes in tumor vasculature. A means of reducing the overall time required to scan multiple cohorts of animals in distinct experimental groups is therefore highly desirable. Multiple-mouse MRI, in which several animals are simultaneously scanned in a common MRI system, has been successfully used to improve study throughput. However, to best utilize the next generation of small-animal MRI systems that will be equipped with an increased number of receive channels, a paradigm shift from simultaneously scanning as many animals as possible to scanning a more manageable number, at a faster rate, must be considered. Given a small-animal MRI system with 16 available receive channels, the simulations described in this work explore the tradeoffs between the number of animals scanned at once and the number of array elements dedicated to each animal for maximizing throughput. An array system consisting of 15 receive and 5 transmit coils allows throughput-optimized acceleration of a DCE-MRI protocol by a combination of multi-animal and parallel imaging techniques. The array system was designed and fabricated for use on a 7.0-T / 30-cm MRI system, and tested for high-throughput imaging performance in phantoms. Results indicate that up to a nine-fold throughput improvement is possible without sacrificing image quality compared to standard single-animal imaging hardware. A DCE-MRI study throughput improvement of just over six times that achieved with conventional single-mouse imaging was realized. This system will lower the barriers for DCE-MRI in preclinical research and enable more thorough sampling of disease pathologies that progress rapidly over time.Item The 2008 U.S. housing crisis and its potential impacts on planning : a comparison of Austin, Atlanta, and Miami(2008) Balwierz, Abel; Kahn, Terry D.The United States is in the midst of a rather severe housing crisis. Home prices have declined and foreclosures have increased in cities all over the country. The crisis began in 2007 and has continued into the fourth quarter of 2008. Some cities have been severely affected by the housing crisis while others have been able to maintain relatively healthy housing markets. This paper demonstrates the local nature of housing markets and the factors which shape them. Analyses of the local housing markets of Austin, TX, Atlanta, GA and Miami, FL comprise the bulk of this paper and demonstrate the broad spectrum of housing market conditions that exist today. The lessons learned from the three case studies finally lead to some recommendations for local planners which could prove effective for creating and maintaining healthy local housing markets.Item 20th century romantic serialism : the Opus 170 greeting cards of Mario Castelnuovo-Tedesco(2005-05) Asbury, David S., 1963-; Holzman, Adam, 1960-; Dell'Antonio, AndrewsItem 20th century romantic serialism: the Opus 170 greeting cards of Mario Castelnuovo-Tedesco(2005) Asbury, David S.; Holzman, Adam; Dell'Antonio, AndrewMario Castelnuovo-Tedesco’s Opus 170 Greeting Cards is a cycle of 51 pieces that span the last two decades of the composer’s life. Intended as musical gifts for his friends and colleagues, he devised a system for assigning each note in the alphabet two musical counterparts using ascending and descending chromatic scales and wrote works that derive their principal themes from the recipient’s name or names. The Greeting Cards are scored for a variety of solo instrument and duo settings, 20 of which were written for the guitar and are the primary focus of this treatise that will have format consisting of Castelnuovo-Tedesco’s biography, an overview of Opus 170 and an examination of specific works. The opus 170 Greeting Cards offer insight into the stylistic traits that characterize Castelnuovo-Tedesco’s music and historical perspective regarding many of the world’s leading musicians from the 1950’s and 1960’s. Research for the treatise has included investigation of published and non-published materials, interviews with those recipients who are still living and musical analysis of the select representative works. Castelnuovo-Tedesco was one the most influential and important musicians of the 20th century. His legacy as a composer and teacher is one that has been largely overlooked in modern scholarship where the common practice of atonal serial composition dominated all other musical styles, especially in academic circles. Castelnuovo-Tedesco always maintained tonal frameworks and a melodic lyricism in his music that in turn caused critics to dismiss him as being unworthy of serious consideration. This treatise, through the examination of one element of the composers work, seeks to help change a general perception that his style, through its conservatism, lacked currency and inventiveness. The Greeting Cards have to date not been studied collectively, leaving a formidable gap in our understanding of the compositional mechanisms employed by this influential and important composer.Item The 21st century classroom : integrating educational technology with 21st century competencies in support of workforce development(2011-05) Bailie, Christine Marie; Treisman, Philip Uri; King, Christopher T.Information and communication technology demands are increasing across a range of occupations, creating intense global competition for highly-skilled workers. In order to meet the economic needs of the next century, education reform must prioritize student-directed learning that fosters innovation and creativity, enabling the United States to compete internationally in attracting and creating high-quality jobs for its citizens. Our system must strive to create lifelong learners and ensure equity in preparing all students for college- and career-readiness, which increasingly, are considered one in the same. Manor New Technology High School, in Central Texas, has successfully used technology immersion and project-based learning to expand the opportunities for its minority-majority population. Emphasis is placed on teaching students how to learn and in making authentic learning connections with the world through applied, and interdisciplinary coursework. An understanding of how educational technology can be used to create better student outcomes, through investment in teacher peer-to-peer supports to effectively integrate technology into instruction, has led to a sustainable and scalable model of technology immersion at Manor Independent School District. Through its partnerships with local businesses and not-for-profit organizations, Manor New Technology High School is graduating highly skilled and college-bound students, while concurrently promoting sector-based economic development within the high-tech industry. State educational agencies are ill-equipped to meet the challenges of workforce development; therefore, new mechanisms and incentives should be created to encourage and enable school districts to pursue 21st Century competencies (analytic skills, interpersonal skills, ability to execute, information processing, and capacity for change), which are enabled through the “invisible tool” of educational technology in the classroom.Item 2D and 3D multiphase active contours without edges based algorithms for simultaneous segmentation of retinal layers from OCT images(2013-05) Klotz, Andrew Criston; Rylander, H. Grady (Henry Grady), 1948-Glaucoma is a common disease that is difficult to diagnosis early using only visual field tests. Current research indicates that determination of retinal nerve fiber layer thickness (RNFLT) can serve as an early indicator of glaucoma [1]. RNFLT is measured by segmenting non-invasive optical coherence tomography images. However, high speckle noise and presence of artifacts in the images cause traditional layer detection and segmentation methods to fail. Multiphase active contours segmentation methods utilize region intensity and shape terms to produce multiple continuous boundaries simultaneously in noisy environments. A 2D and 3D multiphase active contours based algorithm was created to segment synthetic and real human retina OCT images. The 2D multiphase algorithm segmented eight simultaneous layers with a 3.14% mean A-scan error rate per layer. The 3D approach performed qualitatively accurate segmentation of a 20 image stack simultaneously. In an artificial, high-noise image stack the incorporation of more pixels per layer allowed improved segmentation using the 3D algorithm over the 2D. These results indicate that 2D and 3D multiphase active contours algorithms can be used to accurately segment retina layers. With further development to reduce computation time and automate initialization, these algorithms could be used to provide close to real-time clinical retinal image segmentation.Item The 2nd Earl of Essex and the history players : the factional writing of John Hayward, William Shakespeare, Samuel Daniel, and George Chapman(2012-12) Davies, Matthew Bran; Whigham, Frank; Loehlin, James; Barret, J.K.; Friedman, Alan; Levack, BrianRobert Devereux, 2nd Earl of Essex, Queen Elizabeth’s last favorite and the last man she executed for treason, has been harshly treated by posterity. Given his leading role at court in what Patrick Collinson calls the “nasty nineties,” Essex has taken much of the blame for the divisive factional politics of Elizabeth’s final decade. However, leading recent efforts to salvage Essex’s reputation, historian Paul Hammer has uncovered a sophisticated bureaucracy operated by highly educated scholars and led by an intelligent, cultivated statesman. A considerable number of high-profile literary figures, moreover, willingly engaged with this ambitiously expanding Essex faction. This thesis proposes that evidence of interference by the censor and the Privy Council, sensitive to a politicized historiography promoting the Earl’s interests chiefly on London’s stages, discloses the presence of a loose, autonomous federation of authors associated with the Essex and post-Essex factions between 1590 and 1610. This thesis considers the suspected works of an eclectic group of writers bonded by their ideological affiliations with Essex’s “radical moderatism”: civil lawyer John Hayward’s prose history of The Life and Raigne of Henrie IIII (1599); William Shakespeare’s second “tetralogy” (1595-99) dealing with the same historical period; Samuel Daniel’s closet drama of the downfall of the Greek general Philotas (1605); and innovative playwright George Chapman’s double tragedy set in France, The Conspiracy and Tragedy of Charles, Duke of Byron (1608). I situate these authors within the intellectual and public relations wing of the Essex circle in order to consider how they made contact with the center and with each other, and where they resided within the broader operation of the faction; what they offered and what they expected in return; how they shaped political thinking and how their dramaturgy developed as a consequence; whether they were attracted by the purse or the person; and to what extent they were artistically or ideologically motivated. In considering, finally, whether these writers worked in collaboration or alone, on message or off-the-cuff, as propagandists or political commentators, I illuminate the critically neglected role of the factional writer in early modern England.Item 3-D fracture tracing for X-ray computed tomography data(2016-12) Hildebrandt, Jordan; Ketcham, Richard Alan, 1965-; Cardenas, Meinhard B; Sharp, John MX-ray computed tomography (CT) is a nondestructive imaging method that shows differences in X-ray attenuation, which is a proxy for density. Sensitivity to density differences makes CT a good choice for imaging open natural fractures because of the significant density contrast between air and rock. The image data, however, are prone to artifacts and blurring, which makes taking accurate measurements challenging. As a first step to addressing this problem, a tool was created to quantify the spatial resolution of CT data with a point-spread function (PSF). The PSF tool permits accurate measurement of fine-scale features in CT data – critical for measuring fractures, which are often thinner in one dimension than the PSF size, in turn influencing measurement of aperture. The difference between the measurements given by the PSF method and a simple threshold value pick is shown to demonstrate a non-trivial improvement in accuracy. In addition, a 3-D fracture network tracing algorithm was developed, for which the PSF is a necessary input, to characterize accurately the network’s attributes, such as fracture orientations, apertures, and roughnesses. To date, only single, isolated, relatively flat fractures have been characterized thoroughly in 3-D for CT data, and most numerical modeling has been conducted on 2D subsets. Additionally, research involving fracture networks is currently limited to simplified numerical models and simulations. This new work extends CT fracture characterization to the majority of fractured materials with 3-D networks, thus providing a source of real data for studying the difference between fracture networks and single fractures. A sample of Packsaddle schist, with a large number of thin fractures and complex, anastomosing bifurcations, was selected as a testing ground for the network tracing algorithms being developed. Preliminary analysis verifies the method’s efficacy.Item 3D (embodied) projection mapping and sensing bodies : a study in interactive dance performance(2016-12) Beira, Joao Filipe; Strover, Sharon; Pennycook, Bruce, 1949-; Sharir, Yacov; Coelho, António; Penha, RuiThis dissertation identifies the synergies between physical and virtual environments when designing for immersive experiences in interactive dance performances. The integration of virtual information in physical space is transforming our interactions and experiences with the world. By using the body and creative expression as the interface between real and virtual worlds, dance performance creates a privileged framework to research and design interactive mixed reality environments and immersive augmented architectures. The research is primarily situated in the fields of visual art and interaction design. It combines performance with transdisciplinary fields and intertwines practice with theory. The theoretical and conceptual implications involved in designing and experiencing immersive hybrid environments are analyzed using the reality–virtuality continuum. These theories helped frame the ways augmented reality architectures are achieved through the integration of dance performance with digital software and reception displays. They also helped identify the main artistic affordances and restrictions in the design of augmented reality and augmented virtuality environments for live performance. These pervasive media architectures were materialized in three field experiments, the live dance performances. Each performance was created in three different stages of conception, design and production. The first stage was to “digitize” the performer’s movement and brain activity to the virtual environment and our system. This was accomplished through the use of depth sensor cameras, 3D motion capture, and brain computer interfaces. The second stage was the creation of the computational architecture and software that aggregates the connections and mapping between the physical body and the spatial dynamics of the virtual environment. This process created real-time interactions between the performer’s behavior and motion and the real-time generative computer 3D graphics. Finally, the third stage consisted of the output modality: 3D projector based augmentation techniques were adopted in order to overlay the virtual environment onto physical space. This thesis proposes and lays out theoretical, technical, and artistic frameworks between 3D digital environments and moving bodies in dance performance. By sensing the body and the brain with the 3D virtual environments, new layers of augmentation and interactions are established, and ultimately this generates mixed reality environments for embodied improvisational self-expression.