VictorJuiz/thesis huggingface dataset:
Actuated Mobile Sensing in Distributed, Unstructured Environments

Mobile sensor networks present opportunities for improved in situ sensing in complex hydrodynamic environments such as estuarial deltas. This dissertation considers the design and implementation of the mobile sensor network system that was built as part of the Floating Sensor Network project for use in the Sacramento-San Joaquin Delta in California over the 2007-2012 time period. Individual Lagrangian sensor units collect hydrodynamic state information, which is then transmitted to a centralized server and assimilated to produce a state estimate for the entire hydrodynamic system. Physical obstacles, including the shoreline and natural vegetation, present a major challenge to operating mobile sensors in estuarial environments. Actuated mobile sensors are shown to be a viable solution; appropriate control techniques allow these sensors to avoid obstacles, meet navigational goals, and still collect the Lagrangian data necessary for the sensing objective. Issues addressed include physical design, communication techniques for mobile sensor networks, control schemes for fleets of underactuated vehicles in unstructured flow environments, assimilation techniques for mobile Lagrangian data, and field experiments to validate and demonstrate the actuated mobile Lagrangian sensor concept.

Advisor: Bayen, Alexandre M
High Resolution Additive Patterning of Nanoparticles and Polymers Enabled by Vapor Permeable Polymer Templates

The structure and chemistry of nanoparticles and polymers are interesting for applications in electronics and sensors. However, because they are outside of the standard material set typically used for these applications, widespread use of these materials has not yet been realized. This is due in part to the limited ability of traditional manufacturing processes to adapt to these unique materials. As a result, several alternative manufacturing methods have been developed, including nanoimprint lithography, gravure printing, inkjet printing, and screen printing, among many others. However, these current processes are not able to simultaneously produce patterns with high resolution and high dimensional fidelity, rapidly, over large areas, and in a completely additive manner./nIn this work, high-resolution patterns of nanoparticles and polymers are created on a variety of substrates in a completely additive manner using a template-based microfluidic process. Permeation of solvent through a vapor-permeable polymer template is used to both drive the flow of ink and concentrate the solute inside of template features. This fluidic process is shown to allow gradual packing of solute inside the template features, enabling creation of three-dimensional features with low defect densities. Additionally, because the mechanical properties of the template material are found to significantly impact patterning resolution and fidelity, and a process for creating rigid, vapor permeable templates from poly(4-methyl-2-pentyne) is developed. These templates are used for creating patterning of nanoparticles and polymers with a minimum line width of smaller than 350 nm. The process is then applied to the creation of low temperature metallization for polymer electronics using metallic nanoparticles and a highly-sensitive ultraviolet light sensor from zinc oxide nanoparticles.

Advisor: Pisano, Albert P
Observing the Chemistry of Cities: Space-based Spectroscopy of NO2

The atmospheric chemistry of cities depends strongly on the concentration of the hydroxyl radical (OH). OH removes organic molecules (τ = minutes - days), nitrogen oxides (NOx: NO + NO2; τ = 2 - 20 h), and sulfur dioxide (τ = 2 - 3 d) from the atmosphere and forms ozone and particulate matter in the process. The spatial and temporal variability of OH is not fully understood due in large part to its strong nonlinear dependence on the concentration of NOx. In this dissertation, I use measurements of the NO2 column from the Ozone Monitoring Instrument (OMI), a satellite-based UV/Visible spectrometer, and calculations from chemical transport models to investigate the relationship of OH and NOx in urban regions. I characterize the instrumental and model performance necessary to accurately infer OH concentration from space-based measurements of the NO2 column. I use the OMI observations and the WRF Chem model to investigate the spatial variability of the NO2 column over a variety of emission sources. I find, not surprisingly, that a result of the nonlinear dependence of OH on NOx is that the lifetime of NOx depends on the spatial distribution of NOx. Where the nonlinear NOx-OH feedbacks are most important, I find that a spatial resolution of 4 - 8 km is necessary for both model simulations and measurements to accurately capture variations of the NO2 column. Although this result is expected, quantitative analyses of the nonlinear coupling were not previously available and the calculations presented in this dissertation serve as a guide to interpretation of coarse-resolution measurements and models. I investigate the response of the NO2 column observed by OMI to variations of wind speed and day-of-week emission patterns. I find that these high spatial resolution measurements (13 × 24 km2 at nadir) contain independent information on both NOx emissions and removal.

Advisor: Cohen, Ronald C
Optimization of superconducting flux qubit readout using near-quantum-limited amplifiers

Though superconducting qubits offer the potential for a scalable quantum computing architecture, the high-fidelity readout necessary to execute practical algorithms has thus far remained elusive. Moreover, achievements toward high fidelity have been accompanied by either long measurement times or demolition of the quantum state. In this dissertation, we address these issues with the novel integration of two ultralow-noise, superconducting amplifiers into separate dispersive flux qubit measurements. We first demonstrate a flux qubit inductively coupled to a 1.294-GHz nonlinear oscillator formed by a capacitively shunted DC SQUID. The frequency of the oscillator is modulated by the state of the qubit and is detected via microwave reflectometry. A microstrip SQUID (Superconducting QUantum Interference Device) amplifier (MSA) is used to increase the sensitivity of the measurement over that of a semiconductor amplifier. In the second experiment, we report measurements of a flux qubit coupled via a shared inductance to a quasi-lumped element 5.78-GHz readout resonator formed by the parallel combination of an interdigitated capacitor and a meander line inductor. The system noise is substantially reduced by a near-quantum-limited Josephson parametric amplifier (paramp)./nWe present measurements of increased fidelity and reduced measurement backaction using the MSA at readout excitation levels as low as one hundredth of a photon in the readout resonator, observing a 4.5-fold increase in the readout visibility. Furthermore, at low readout excitation levels below one tenth of a photon in the readout resonator, no reduction in T1 is observed, potentially enabling continuous monitoring of the qubit state. Using the paramp, we demonstrate a continuous, high-fidelity readout with sufficient bandwidth and signal-to-noise ratio to resolve quantum jumps in the flux qubit. This is enabled by a readout which discriminates between the readout pointer state distributions to an error below one part in 1000. This, along with the ability to make many successive readouts in a time T1, permits the use of heralding to ensure initialization to a fiducial state, such as the ground state. This method enables us to eliminate errors due to spurious thermal population, increasing the fidelity to 93.9%. Finally, we use heralding to introduce a simple, fast qubit reset protocol without changing the system parameters to induce Purcell relaxation.

Advisor: Clarke, John
Linear, Low Noise Microwave Photonic Systems using Phase and Frequency Modulation

Photonic systems that transmit and process microwave-frequency analog signals have traditionally been encumbered by relatively large signal distortion and noise. Optical phase modulation (PM) and frequency modulation (FM) are promising techniques that can improve system performance. In this dissertation, I discuss an optical filtering approach to demodulation of PM and FM signals, which does not rely on high frequency electronics, and which scales in linearity with increasing photonic integration. I present an analytical model, filter designs and simulations, and experimental results using planar lightwave circuit (PLC) filters and FM distributed Bragg reflector (DBR) lasers. The linearity of the PM and FM photonic links exceed that of the current state-of-the-art.

Advisor: Wu, Ming C
The Role of Folklore Study in the Rise of Russian Formalist and Czech Structuralist Literary Theory

Russian formalism and Czech structuralism are understood to have initiated the study of literature as a self-sufficient discipline by applying linguistic concepts to the analysis of literary texts. This dissertation seeks to enrich our understanding of this development by examining the transition from linguistics to literary theory from an intellectual-historical perspective. My thesis is that folklore study played a crucial role in the rise of formalist and structuralist literary theory by serving as a mediating field between language and <&ldquo>high literature. Folkloristics, which traditionally approached its subject matter through linguistic theory, understood verbal art to behave like language<&mdash>--as an impersonal repertoire of poetic forms which adhere to regular laws governing their usage and evolution. This body of scholarly work provided early literary theorists with a model for theorizing literature or art as a law-abiding, <&ldquo>scientific object of study akin to language./nThe transfer of ideas from the field of folkloristics to literary theory was the product of scholarly training, personal intellectual exchange, and institutional affiliations. In the first chapter I focus on Victor Shklovsky's use of A. N. Veselovsky's writings to develop a universalist theory of narrative structure in his Theory of Prose . Drawing on Roman Jakobson's The Newest Russian Poetry and his work on the Cyrillo-Methodian legacy, the second chapter illustrates parallels between Jakobson's conceptions of literary value and literary evolution and the work of his teacher V. F. Miller. The last chapter argues that Jan Mukařovský's Aesthetic Function, Norm and Value as Social Facts drew on P. G. Bogatyrev's functional structural ethnography and compares their respective conceptions of the semiotic collective./nBy tracing these intersections, we can see how the emergence of theory intended to explain <&ldquo>high literature was galvanized by moments of contact with folklore studies. Highlighting the role that folkloristics played in the work of these three pioneering literary theorists (Shklovsky, Jakobson and Mukařovský) allows us to better understand the emergence of twentieth-century literary theory as an autonomous discipline.

Advisor: Paperno, Irina
Investigation of the hydrophobic/steric ratchet mechanism of the anthrax toxin φ clamp

Transmembrane protein translocation is a fundamental and ubiquitous process that operates under several conserved principles. Protein conducting machines, known as translocase channels, catalyze the unfolding and subsequent transport of substrate proteins through narrow pores in an energy-dependent manner. Investigating how translocase machines rectify external energy inputs is key to understanding their force transduction mechanisms and overall function. Molecular ratchets are believed to be an integral mechanism for providing directional polypeptide transport through translocase channels, and several types of ratchets have been identified in these machines./nIn this work, anthrax toxin, a protein translocase that possesses a hydrophobic gasket known as the φ clamp, is used as a model system to investigate the role of hydrophobic/steric ratcheting in/nprotein translocation. Planar lipid bilayer electrophysiology was used to establish that the PA φ clamp binds hydrophobic/aromatic residues in peptide substrates, and to determine the consequences this binding interaction has on transport of these peptides. Under conditions where protein unfolding is shown to be rate-limiting, sequences identified as φ-clamp interacting increase translocation of folded downstream domains./nSingle channel electrophysiology was used to record substrate and driving force dependent changes in the conductance of a single PA channel. Open, bound, and two intermediate conductance states are identified, which we hypothesize correspond to different conformations of the catalytic φ-clamp loop. Crystallographic evidence, which supports this theory, is presented. A kinetic analysis of single channel peptide binding and translocation events shows that the translocation pathway for hydrophobic/aromatic sequences has committed steps. A hydrophobic ratchet model is proposed to explain φ-clamp catalysis and how the favorable interaction between the clamp and hydrophobic/aromatic sequences may favor unfolding and increase directional movement of the translocating chain.

Advisor: Krantz, Bryan
Multiexponential T2 and Diffusion Magnetic Resonance Measurements of Glioma Cells

Using monoexponential models, magnetic resonance (MR) parameters transverse relaxation time (T2) and apparent diffusion coefficient (ADC) have been used to non–invasively assess cell density, which characteristically increases with brain tumor malignancy. Multiexponential models of T2 and ADC may allow for a more accurate evaluation of cell density than the traditionally used monoexponential model. To better understand how cell density affects multicomponent T2 and ADC, tumor models with a range of cell densities were created by suspending astrocytoma cells in agarose at different densities. T2 was measured using a Carr–Purcell–Meiboom–Gill (CPMG) sequence with 64 echo times. ADC was measured using a diffusion–weighted sequence with 32 b–values. Three models were used to fit the data and determine the T2 values, ADC values, and associated fractions: monoexponential, biexponential, non–negative least squares (NNLS). Spearman Rank was used to test the correlation with cell density./nBoth the monoexponential T2 and ADC were significantly negatively correlated with cell density. The biexponential model identified two T2 components, short and long. Both T2 components’ values and fractions were significantly correlated to cell density. The biexponential model identified two ADC components, slow and fast. Both ADC components’ values were significantly correlated with cell density, but not the fractions. The NNLS model identified up to three T2 and three ADC components. For the NNLS identified T2s, the components were labeled short, medium, and long. Both the NNLS short and medium T2 values and fractions were significantly correlated with cell density. For the NNLS identified ADCs, the components were labeled slow, intermediate, and fast. Only the fast fraction was significantly correlated with cell density./nThe NNLS components obtained from samples of packed cells were further evaluated by washing the samples with a gadolinium contrast agent (Gd–DTPA) to shorten the T2 associated with the extracellular space. Gd–DTPA did not affect the short T2, which was considered to be associated with the intracellular space. The medium T2 component was no longer identified in samples with Gd–DTPA and was considered to be associated with the extracellular space. Overall, the results suggest that separately measurable components exist that could be utilized for compartment specific information.

Advisor: McKnight, Tracy R
Speech Analysis Methodologies towards Unobtrusive Mental Health Monitoring

The human voice encodes a wealth of information about emotion, mood and mental states. With the advent of pervasively available speech collection methods (e.g., mobile phones) and the low-computation costs of speech analysis, it suggests that non-invasive, relatively reliable, and modestly inexpensive platforms are available for mass and long-term deployment of a mental health monitor. In the thesis, I describe my investigation pathway on speech analysis to measure a variety of mental states, including affect and those triggered by psychological stress and sleep deprivation./nThis work has contributions in many folds, and it brings together techniques from several areas, including speech processing, psychology, human-computer interaction, and mobile computing systems. First, I revisited emotion recognition methods by building an affective model with a naturalistic emotional speech dataset, which is consisted of a realistic set of emotion labels for real world applications. Then, leveraging the speech production theory I verified that the glottal vibrational cycles, the source of speech production, are physically affected by psychological states, e.g., mental stress. Finally, I built the AMMON (Affective and Mental health MONitor) library, a low footprint C library designed for widely available phones as an enabler of applications for richer, more appropriate, and more satisfying human- computer interaction and healthcare technologies.

Advisor: Canny, John F
Healing Lessons: Urban High School Teachers Learning to Teach Black Youth with Post-Traumatic Stress Disorder

Significant research reveals that youth who reside in neighborhoods of high crime and violence can often be exposed to external stressors that result in Post-Traumatic Stress Disorder (PTSD). These youths are disproportionately Black, and this condition often goes untreated. Consequently, their challenges with PTSD can surface and have tremendous impacts on teaching and learning at the schools they attend. These impacts include severe problems with academic achievement and discipline. The site of this research is a public, urban continuation high school in Northern California where many students exhibit symptoms of PTSD. This study explored the outcomes of professional development (PD) sessions designed to better prepare teachers to work with students who have exhibited behaviors connected to traumatic experiences. A mental health therapist led the first two sessions and assisted a focal teacher who was certified in cognitive behavioral therapy (CBT) in presenting the final session. Data sources are videotapes of the PD sessions, audio taped interviews of participating teachers, teacher surveys, observations, and field note documentation of the teachers' classroom instruction. Findings indicated that teachers found the PD sessions highly effective in helping them to better understand student behaviors as well as ways that they themselves were vicariously affected by their students' traumatic experiences. This study also found that mental health training helped teachers re-conceptualize their approaches to curriculum and instruction. Finally, this research explored the effects of the PD on implementation across the range of disciplines that were taught. A key implication is that when mental health training is incorporated into PD in urban schools, ameliorative impacts for both students and teachers are achieved. Teachers who learn about the effects of and pedagogical responses to PTSD are better prepared to create effective learning environments for traumatized students.

Advisor: Mahiri, Jabari
Planning Beirut: For the War Yet to Come

This dissertation investigates the spatial practices through which Beirut's post-civil war (1975-1990) peripheries have been transformed into sectarian frontiers of urban growth mired in new forms of urban conflict. Based on ethnographic and archival research in three peripheral areas of Beirut (2009-2010) and building on ten years of urban research and practice in Beirut, this study examines the intervention of religious-political organizations -- such as Hezbollah, the Druze Progressive Socialist Party, the Maronite Church, and the Sunni Future Movement -- in the design and implementation of urban planning and zoning policies, execution of infrastructure projects, operations of land and housing markets, and legislation of property and building laws as part of their territorial battles over land in Beirut. This research shows how these spatial practices are articulated within imagined and planned geographies of local and regional wars "yet to come."/nThis dissertation makes three contributions. First, the study demonstrates how these religious-political organizations play a significant role in ordering the present through their role in the futures of violence with severe repercussions on the environment, displacement, and future cycles of violence in the city. The project hence positions such complex actors -- whose practices do not always fit neatly in the binaries of private-public or state-market -- at the center of how cities in both the Global South and the Global North are restructured. Second, this study challenges the common conception of planning as a tool through which to order the present for a projected better future (via resource management, spatial justice, redistribution, risk mitigation, etc.). Specifically, it shows how, by becoming decoupled from the question of development, the practice of urban planning in Beirut involves innovative techniques that aim to "balance" spatialities of political difference in order to keep a war at bay. Simultaneously, these techniques allow for urban growth and development profit. Third, this work illustrates how the production of sectarian difference is unstable and contested like the spaces of conflict, domination, and profit it shapes in its image. The spatialities of the sectarian political order are constantly being negotiated, reconfigured, and reproduced, re-defining in turn what "sectarianism" comes to mean at each historical moment./nMethodologically, this study rethinks the ways in which cities in the Global South are often conceptualized: a binary between the city's center and its marginalized peripheries. By illustrating how the "peripheries" of Beirut are centers in the transnational landscapes of finance, conflict, and resistance ideologies, with their own peripheries and frontiers, the project calls for an alternative approach to conceptualizing cities in the Global South.

Advisor: Roy, Ananya