VictorJuiz/thesis huggingface dataset:
Neo-Aztec aesthetics and mytho-historical critique [electronic resource] : the return of Quetzalcóatl in the Mexican intellectual imagination [1925-1950]

This work examines the appearance of the Mesoamerican god of civilization and humanity Quetzalcóatl in modern Mexican literature. In selected critical and philosophical writings of José Vasconcelos and Octavio Paz, the ancient Quetzalcóatl transforms into a proposed neo-Aztec mythology, which functions as a medium for these writers to express a distinct critique of Mexican history. This mythology reinforces an Indianist Vanguard aesthetic, based on primary accounts of the Aztec civilization, and revolves around Quetzalcóatl emerging as a post-revolutionary Mexican cultural and poetic hero. An analysis of this nature informs contemporary studies on pre-Hispanic myth and anthropology in modern Latin-American literature. The contribution of this work supplements the limited studies on the under-explored theme of pre-Hispanic myth in Mexican and Latin-American cultural and intellectual discourse as well. On a wider scale, this critical analysis offers a unique perspective of the trans-historical and heterogenous re-configuration of ancient myth systems and symbols in the modern literary imagination.

Keywords: Iberian and Latin American Cultures
Advisor: Ruffinelli Jorge primary advisor. Thesis advisor
Hoyos Ayala Héctor advisor. Thesis advisor
Rocha Marília Librandi advisor. Thesis advisor
Network models and infectious disease control [electronic resource] : analysis and insights

Many models of infectious disease do not explicitly consider the underlying contact network through which the disease spreads. However, network structure can greatly influence the dynamics of an epidemic and has implications for infectious disease control policies. This dissertation explores two important themes of network science as it relates to infectious disease control policy: first, how to incorporate network structure into the modeling and evaluation of infectious disease control policies; and second, how to leverage network structure in the design of optimal control policies. Complete network information is rarely available. Furthermore, even when network data is available, it generally only represents a snapshot in time and does not capture population or network dynamics (e.g., the formation and dissolution of contacts). In Chapter 2, we address these data limitations and describe a general simulation framework for modeling the spread of infectious disease in a dynamic contact network. We provide a methodology for inferring important model parameters, such as those governing network structure and network dynamics, from readily available data sources. In Chapter 3, we present an application of this framework in evaluating the effectiveness and cost-effectiveness of mass media campaigns aimed at reducing concurrent sexual partnerships in sub-Saharan Africa for HIV prevention. In Chapter 4, we address the problem of leveraging network structure in designing infectious disease control policies. In particular, we consider the problem of identifying which links to remove from a contact network in order to maximize the number of individuals who are protected from infection. We show that this problem can be posed as a non-convex quadratically-constrained quadratic program (QCQP), from which a link removal algorithm can be derived. Evaluation of the QCQP algorithm on standard network models demonstrates that it exhibits near-optimal performance and outperforms other intuitive link removal algorithms, such as removing links in order of edge centrality.

Keywords: Electrical Engineering
Advisor: Brandeau Margaret L. primary advisor. Thesis advisor
Bambos Nicholas advisor. Thesis advisor
Johari Ramesh
Networked to the catalytic core [electronic resource] : structure-function studies of RNA enzymes reveal distinct connections from the periphery

The past two decades of functional and structural studies on RNA enzymes have largely focused on revealing active site interactions between ribozymes and their substrates. More recently, active site interactions among ribozyme residues themselves and the substrate have revealed an intricate network of interactions in and around the active site that involves metal ions, metal ion ligands, hydrogen bonding, and stacking interactions. Does this network extend into the broader structure of the RNA? The current studies in this thesis are aimed at understanding how the overall structural scaffold of RNA is involved in catalysis. Peripheral elements that are brought into close proximity via long-range tertiary contacts surround the catalytic core of most group I introns. In the well-studied Tetrahymena group I intron, ablation of each of five long-range tertiary contacts destabilizes the folded ribozyme, indicating a role for these tertiary contacts in overall stability, as expected. But once folded, three of the five tertiary contact mutants exhibit distinct functional roles in catalysis. Structural changes distal from the mutation site, revealed by hydroxyl radical footprinting, suggest that that these contacts are coupled to the catalytic core from a distance. These structural data combined with X-ray crystal structures and phylogenetic data suggest a number of networks that structure functional sites by using long-range tertiary contacts to position rigid helices and their more local tertiary interactions relative to the rest of the RNA. Preliminary data that tests these hypotheses suggest that some, but not all, of these networks between the periphery and the functional sites may be conserved among group I introns and that long-range tertiary contacts as well as more local tertiary interactions such as base triples may act redundantly to maintain the structure of the same regions of RNA. This redundancy could allow RNAs that change conformation over their reaction cycles to rearrange only a few tertiary contacts while maintaining a global fold. With the studies described herein, we are poised to understand the structural networks that couple the peripheral regions of RNA to its catalytic sites. These insights may lead to a better understanding of how structural networks of communication are exploited to facilitate multi-step processes that are driven by more complex RNA enzymes like the ribosome and the spliceosome.

Keywords: Chemistry
Advisor: Herschlag Daniel primary advisor. Thesis advisor
Boxer Steven G. (Steven George)
Khosla Chaitan
A new approach to predicting analyst forecast errors [electronic resource] : do investors overweight analyst forecasts?

I provide evidence that investors overweight analyst forecasts by demonstrating that prices do not fully reflect predictable components of analyst errors, which conflicts with conclusions in prior research. I highlight estimation bias in traditional approaches and develop a new approach that reduces this bias. I estimate 'characteristic forecasts' that map current firm characteristics into forecasts of future earnings. Contrasting characteristic and analyst forecasts predicts analyst forecast errors and revisions. I document abnormal returns to strategies that sort firms by predicted forecast errors, consistent with investors overweighting analyst forecasts and predictable biases in analyst forecasts influencing the information content of prices.

Keywords: Business.
Advisor: Lee Charles M. C. primary advisor. Thesis advisor
Barth Mary E. advisor. Thesis advisor
Larcker David F. advisor. Thesis advisor
Piotroski Joseph D. (Joseph David) advisor. Thesis advisor
New materials systems for aqueous batteries [electronic resource]

Existing battery technologies do not offer the cycle life, power, energy efficiency, or low cost needed for widespread adoption on the electric power grid. In the first part of this thesis, the development of aqueous lithium ion batteries is discussed. In the second part of this thesis, the use of Prussian Blue analogues as battery electrodes in aqueous potassium ion and sodium ion cells is presented. These materials have extremely fast kinetics and long cycle life when operated as battery electrodes in aqueous electrolytes. The effects of insertion species and electrode composition on the performance of Prussian Blue analogue electrodes were characterized in aqueous half-cells. Cycle lives of up to 40,000 cycles and high rate capability (over 80C) were observed for these electrode materials. Full cells were built using a copper hexacyanoferrate cathode, an activated carbon/conductive polymer anode, and an aqueous potassium ion electrolyte. These batteries batteries show promise for stationary storage applications including those on the electric grid.

Keywords: Materials Science and Engineering
Advisor: Cui Yi
Dionne Jennifer Anne advisor. Thesis advisor
Huggins Robert A. (Robert Alan)
New results on the singularity analysis of the Kaehler-Ricci flow [electronic resource]

In this thesis, we study the singularity development of the Kaehler-Ricci flow on holomorphic fibrations, and classify the singularity models of some classes of fibrations using parabolic rescaling. We first study the collapsing behavior of Calabi-Yau fibrations under the Kaehler-Ricci flow. A compact Kaehler manifold with semi-ample canonical line bundle admits a fibration of Calabi-Yau manifolds with possibly singular fibers. The convergence behavior for this class of manifolds under the Kaehler-Ricci flow was first studied by Song and Tian who establish the metric convergence in the sense of currents. In this thesis, we obtain the optimal collapsing rate of the nonsingular Calabi-Yau fibers, thus improving Song and Tian's work in analytic and geometric aspects. Secondly, we focus on a specific type of holomorphic fibration, namely the CP^1-bundles over Kaehler-Einstein manifolds. Fiber collapsing in the sense of Gromov-Hausdorff convergence was shown to occur in this case by Song, Szekelyhidi and Weinkove. We study the finite-time singularities for these manifolds using parabolic rescaling and dilation procedures adapted from Hamilton and Perelman in their works of the Ricci flow on 3-manifolds. We prove that when the flow metric has cohomogeneity-1 symmetry the collapsing occurs as a Type I singularity and we show that the singularity is modelled by C^n X CP^1.

Keywords: Mathematics
Advisor: Schoen Richard (Richard M.) primary advisor. Thesis advisor
Brendle Simon
White Brian
Noise coupling analysis for mixed signal systems [electronic resource]

Trends toward portable electronics are leading forces in developing new systems. Accordingly, two features have become crucial in implementing these integrated systems: wireless communication and efficiency in size and energy consumption. Efforts to facilitate both digital and analog features produce mixed signal System-On-Chip (SOC), which include both analog and digital functions on a single die. Noise coupling in such an environment is a key issue in improving system performance; in particular, the noise coupling through the common substrate (i.e. substrate noise) is unavoidable as physical separation between the functions shrinks with technology scaling. To prevent the system performance from degenerating due to the substrate noise, methodologies for analyzing, estimating and measuring the noise in both simulated and practical conditions are essential and worthy of full investigation. This dissertation has conducted such an investigation in mixed signal SOCs Overall, this dissertation presents methodologies regarding how to understand, estimate, and measure the substrate noise in the mixed-signal SOC. As long as mixed-signal systems prevail in the integrated electronics industry, the SOC as well as the SIP should become the main frames of system implementations, and the presented research can contribute to shaping these frames.

Keywords: Electrical Engineering
Advisor: Dutton Robert W. primary advisor. Thesis advisor
Wong S. Simon primary advisor. Thesis advisor
Mitra Subhasish advisor. Thesis advisor
Non-equilibrium effects and multiphase flow in porous media [electronic resource]

We encounter flow in porous media, knowingly or otherwise, on a daily basis; percolation of precipitation into top soil, ground-water supplies obtained from aquifers (ground-water hydrogeology), ground-water contamination studies and remediation thereof, recovery of oil and gas be it primary, secondary, or tertiary (enhanced-oil-recovery), and storage of Carbon-Dioxide in saline aquifers are just a few examples. Our fundamental understanding of the physics of multiphase flow in porous media is the cornerstone of all endeavors to develop mathematical descriptions and use models to make predictions and decide on the proper course of action in efforts to utilize such resources. The objectives of this research are to investigate the relevant physical mechanisms responsible for instabilities in flow dynamics via detailed experimentation and to incorporate the findings in mathematical models that improve upon the predictive capabilities of current models. This work starts with an experimental program comprising a series of core-scale drainage displacement experiments using pairs of immiscible fluids covering a wide range of viscosity ratios. The experiments are designed and carried out with a focus on the fluid mechanics of drainage processes. The analysis of the experimental observations clearly shows the time-evolution of constitutive relationships and flux functions in the formulation of multiphase flow in porous media. A self-consistent general formulation for multiphase flow in porous media is developed that is firmly based in physics observed in core-scale and micromodel experiments. We account for nonequilibrium effects by considering redistribution time and treat saturation by evolving locally moving time-averages of the saturation. The proposed abstraction provides a non-zero temporal support for constitutive relationships for porous media. Several families of models arise from approximations to the general formulation with various degrees of accuracy. The classical Buckley-Leverett and Barenblatt expressions are examples of these families. We explore the behaviors of a number of special cases arising from the proposed general formulation using established and novel numerical schemes by providing nonlinear physics-based preconditioning to reduce the stiffness inherent in models derived with higher orders of accuracy of approximation. Finally, results of numerical simulations of these models are presented and comparison is made with experimental observations. The agreement observed between numerical and experimental results demonstrates the consistency of the proposed abstraction.

Keywords: Energy Resources Engineering.
Advisor: Kovscek Anthony R. (Anthony Robert) primary advisor. Thesis advisor
Castanier Louis M. advisor. Thesis advisor
Tchelepi Hamdi advisor. Thesis advisor
Nonlinear frequency conversion in III-V semiconductor photonic crystals [electronic resource]

Nonlinear optical processes provide a physical mechanism for converting the frequency of light. This allows the generation of tunable light sources at wavelengths inaccessible with lasers, leading to a diverse set of applications in fields such as spectroscopy, sensing, and metrology. To make these processes efficient has conventionally required relatively exotic materials that are incompatible with state of the art nanofabrication, resulting in large-area devices that operate at high optical powers and cannot be integrated with on-chip optical and electronic circuits. This dissertation shows how optical nanocavities, by localizing light into sub-cubic optical wavelength volumes with long photon storage times, can greatly enhance the efficiency of nonlinear frequency conversion processes in III-V semiconductors, while simultaneously shrinking the device footprint, reducing the operating power, and providing a scalable on-chip platform. This approach also enables on-chip quantum frequency conversion interfaces, which are crucial for the construction of quantum networks. First, photonic crystal nanocavities in gallium phosphide are shown to generate second harmonic radiation with only nanowatts of coupled optical powers, and efficiency many orders of magnitude greater than in previous nanoscale devices. This approach is then extended to demonstrate sum-frequency generation in GaP photonic crystal cavities with multiple cavity modes, as well as broadband upconversion employing photonic crystal waveguides. The nanocavity-enhanced second harmonic generation is then integrated with a single quantum dot to create a single photon source triggered at 300 MHz by a telecommunication wavelength laser coupled with an external electro-optic modulator, a simpler and faster configuration than standard approaches. The efficiency of all the aforementioned processes can be further improved through resonant photonic crystal nanocavities allowing large frequency separation, which are described in this thesis. Finally, this dissertation presents spectroscopic measurements of quantum systems that emit photons at visible wavelengths, which are promising candidates for a number of quantum and classical applications and well-suited for integration with on-chip frequency conversion.

Keywords: Electrical Engineering
Advisor: Vuckovic Jelena primary advisor. Thesis advisor
Fan Shanhui
Miller D. A. B. advisor. Thesis advisor
Non-proportional hazards in clinical trials with failure-time endpoints [electronic resource]

In clinical trials, enrolled patients are randomized into treatment and control groups to test if the new treatment has advantages over the control. Data have been collected from both groups to form test statistics. For life-threatening diseases, such as cancer and heart attacks, the primary endpoint of a confirmatory trial for a new treatment is time to failure. This endpoint often involves censored data because some subjects may not fail by the end of the study or may have been lost to follow-up. To handle survival data in the problem of explanatory variables, Cox (1972) introduced a semi-parametric model based on the assumption of proportional hazards. In this model, the log ratio of the hazard function of the treatment group to that of the control group is a constant that does not vary over time. Earlier Mantel (1966) introduced the logrank test that is asymptotically efficient for proportional hazards alternative. Both logrank test and proportional hazards regression model have become standard procedures in clinical trials with survival endpoints. Since clinical trials can run for years, interim analyses by a Data and Safety Monitoring Board (DSMB) are typically included in the trial protocol. This led to the development of ``time-sequential'' methods for early stopping during interim analyses. Lan and DeMets (1988) have noted that there are two time scales in time-sequential trials. One is the calendar time t at which interim analysis is carried out, and the other is the information time V(t), which can be measured by the variance of the test statistic (under the null hypothesis) based on all the data collected up to time t and is unknown before time t. Therefore, to determine the sample size and study duration, assumptions have to be made on the accrual rate, the survival distribution of both treatment and control groups, and the censoring distribution. These assumptions are commonly based on the literature concerning related studies and on educated guesses. In particular, since logrank tests and time-invariant hazard ratios are typically used to summarize the results of the studies, it is convenient to assume proportional hazards as the working model at the design stage. During interim analyses, marked discrepancies for the assumptions at the design stage may be observed. Herein we propose a group sequential design that addresses theses discrepancies and thereby makes the trial more efficient in terms of power, study duration and expected sample size. The design allows one to combine the logrank statistic with the more powerful test statistics in case of non-proportional hazards at the terminal stage. A new approach to futility stopping is developed as well as a piecewise constant hazard ratio model replacing the proportional hazards model.

Keywords: Statistics
Advisor: Lai T. L. primary advisor. Thesis advisor
Lavori Philip W.
Shih Mei-Chiung advisor. Thesis advisor
Nonvolatile monolithic three-dimensional field programmable gate array with stacked resistive configuration memory [electronic resource]

The majority of conventional Field Programmable Gate Arrays (FPGAs) store their configuration bits in Static Random Access Memory (SRAM) on chip. Configuration SRAM is the primary contributor to the large area, power consumption and delay of FPGAs relative to Application Specific Integrated Circuits (ASICs). The solution is a Three-Dimensional (3D) FPGA, in which the configuration memory is vertically stacked over programmable logic and routing fabric. Several 3D-FPGA concepts with various integration schemes and alternative memory technologies for the configuration memory have been demonstrated recently. However, those concepts required materials and process that may not be compatible or scalable with standard CMOS process. This dissertation presents the first experimental 3D-FPGA with monolithically stacked configuration memory based on the emerging Resistive Random Access Memory (RRAM) technology, which is compatible and scalable with CMOS process. The RRAM, here, are not used in a typical FLASH memory application. Rather, they are used as programmable resistors to construct configuration memory cells that store and represent active static logic. To demonstrate the concept, a 1Kbit nonvolatile resistive configuration memory array and a 17x17-tile 3D-FPGA with 21Kbit configuration are fabricated and tested. This dissertation delves into the architecture, design, implementation, fabrication and validation of the memory array and 3D-FPGA prototypes. Both prototypes are implemented in 0.18um general purpose CMOS process with 1 poly-silicon and 6 metal layers. The programmable resistors (RRAM) are sandwiched between the 5th and 6th metal layers. The measurement results demonstrated the concept of resistive configuration memory and confirmed the programmability and logic functionality of the RRAM based 3D-FPGA. This dissertation also projects the potential improvements in area, energy consumption and delay of the RRAM based 3D-FPGA over conventional SRAM based design, when the prototype is scaled to advanced 65nm CMOS technology. Simulation result shows 40% reduction in area is expected. This work also examines the potential benefits of monolithic 3-layer 3D-FPGA, designed also in the 65nm node. Simulation results show that 70% area reduction is expected.

Keywords: Electrical Engineering
Advisor: Wong S. Simon primary advisor. Thesis advisor
El Gamal Abbas A. advisor. Thesis advisor
Pease R. (R. Fabian W.) advisor. Thesis advisor