VictorJuiz/thesis huggingface dataset:
Justice by Geography: After Proposition 57, Some Kids Left in Legal Limbo
Keywords:  Department of Communication
Juvenile Justice
California
Proposition 57
Direct File
Thesis

Last November, Californians voted to eliminate direct filing – a procedure that gave prosecutors exclusive power to decide whether to try youth as adults. Direct file was being applied unevenly across counties in California and it targeted youth of color at alarming rates. Champions of juvenile justice reform celebrated. Now, judges – who are seen as more impartial - decide who to send to adult court. But seven months after Proposition 57’s passage, some prosecutors are still fighting to keep minors – whose trials began before last November - in adult court, putting those kids’ futures in limbo.
Kant and the structure of the given [electronic resource]
Keywords: Philosophy.

The aim of this dissertation is to provide an interpretation that can resolve the prima facie tension between Kant's simultaneous commitment to the duality of the faculties (the Duality Principle) and the claim that they must work together to produce cognition (the Togetherness Principle). This tension is at the center of the recent debate between conceptualist and nonconceptualist interpretations of the Critique of Pure Reason. I aim to resolve the tension by accommodating Kant's commitment to the non-conceptual nature of space and time (the Duality Principle) while explaining the fundamental role of the understanding not only in judgment but also in perception (the Togetherness Principle). Drawing on the contemporary distinction between the content of perception and the requirements for the possession of that content, I argue that the primary content of empirical and pure intuition is non-conceptual. Against most nonconceptualists, however, I argue that this content can only be "given" to subjects who possess certain conceptual capacities that, for Kant, are fundamentally linked to the conditions for the unity of apperception. There is an important sense in which conceptual capacities transform what is given in intuition, so that what Kant calls "perception" involves the introduction of a conceptual structure into the non-conceptual given.
Laboratory study on the effects of carbonates and clay content on viscoplastic deformation of shales at reservoir conditions [electronic resource]
Keywords: Geophysics.

Inelastic time-dependent deformation or viscoplsatic behavior in clay-rich and carbonate-rich reservoir rocks causes wellbore instability in the scale of days, changes the response to hydraulic fracturing stimulation in the scale of years, and it also can change the state of stress in sedimentary basins in the larger time scales of millions of years. The main focus of this thesis is on how the inelastic time-dependent deformation affects hydraulic fracturing operations in unconventional oil and gas reservoirs. Horizontal drilling and hydraulic fracturing developments have made hydrocarbon production from very low-permeable unconventional reservoirs economically feasible. Hydraulically stimulated fractures propagate perpendicular to the direction of least principal stress, while the state of stress determines the growth of these fractures. Viscoplastic rock formations are more likely to have higher values of the least principal stress (or frac gradient), which makes them potential barriers to vertical hydraulic fracture propagation. In this thesis, I have studied viscoplasticity of rock samples from different formations using conventional experimental methods at various reservoir conditions. Additionally, I have used multi-scale imaging techniques to investigate the sources of inelastic deformations in shale rocks.
Large-scale inference with block structure [electronic resource]
Keywords: Statistics.

The detection of weak and rare effects in large amounts of data arises in a number of modern data analysis problems. Known results show that in this situation the potential of statistical inference is severely limited by the large-scale multiple testing that is inherent in these problems. Here we show that fundamentally more powerful statistical inference is possible when there is some structure in the signal that can be exploited, e.g. if the signal is clustered in many small blocks, as is the case in relevant applications. We derive the detection boundary in such a situation where we allow both the number of blocks and the block length to grow polynomially with sample size. This result recovers as special cases the heterogeneous mixture detection problem (1) where there is no structure in the signal, as well as scan problem (2) where the signal comprises a single interval. We develop methodology that allows optimal adaptive detection in the general setting, thus exploiting the structure if it is present without incurring a penalty in the case where there is no structure. The advantage of this methodology can be considerable, as in the latter case the means need to increase at the rate of square root of the log of the problem size to ensure detection, while in the former case the means may decrease at a polynomial rate. The identification version of this problem is also considered in this thesis, where the length of the block is allowed to grow polynomially with the sample size while the number of blocks is assumed to grow at most logarithmically with the sample size. This setting greatly generalizes previous results. The multivariate version of this problem is also considered, in which we try to identify the support of the rectangular signal(s) in the hyper-rectangle. A lower bound below which the identification is impossible is presented and an asymptotically optimal and computationally efficient procedure is proposed under Gaussian white noise. This signal identification problem is shown to have the same statistical difficulty as the corresponding detection problem, in the sense that whenever we can detect the signal, we can identify the support of the signal. We also discuss about the signal identification problem under the exponential family setting and the robust identification problem where the noise distribution is unspecified.
Level Up Languages: Contextualizing Foreign Language Learning Through Text-Based Adventure Games
Keywords: Language Learning
Task-Based Language Teaching
Gaming
Computer Assisted Language Learning
Digital Game-Based Language Learning
Thesis

Outside of formal language classrooms, the resources to learn a foreign language are limited. Many people traveling abroad turn to technology for help, and take advantage of free language learning apps like Duolingo. However, users of these programs often feel like they can’t transfer what they’ve learned from the app to a real-world interaction where they want to accomplish a specific communicative goal. Research has pointed to contextualized practice to help with transfer, and the pedagogical approach of Task-Based Language Teaching (TBLT) lends itself well to this practice. However, the most popular language learning apps do not use TBLT in their approach to language teaching because of the difficulty of incorporating such a complex instructional system into their simplified instructional mechanics. One area of technology that can easily incorporate TBLT into its instructional approach is video games. Research supports the benefits of video games for learning as well as the relevance of TBLT in gaming. Several language games currently use TLBT as their pedagogical model; however, of those that are available to the public, none incorporate contextualized tasks into a larger cohesive game narrative. To address this gap, I propose to incorporate authentic, contextualized, and relevant tasks for the motivated traveler within the engaging narrative of a text-based adventure computer game. My solution focuses on 1) addressing essential language for travel and 2) increasing learner engagement by contextualizing learning through story narrative.
Leveraging similarity in statistical learning [electronic resource]
Keywords: Statistics.

Machine learning literature has provided a toolbox of techniques for general use by the modern applied statistician. For some data analysis, these methods can be improved to yield better results based on the properties of the data in question. In this manuscript, we develop methodology for three different problems in which, in some sense, similarity can be leveraged to make better predictions, as demonstrated in baseball and epidemiology applications. First, we propose adding a penalty on the nuclear norm of the regression coefficient matrix in multinomial regression to learn which outcomes are similar. Second, we propose adding a clustering step to l1 penalized regression, to build customized training sets of observations that are similar to the test set. Third, we propose and evaluate several approaches to mining electronic medical records to support physician decision-making with data on patients similar to a patient in question. This last problem is especially challenging because of the observational and high-dimensional nature of the data.
Literature and existentialism in Italy [electronic resource] : history and interpretation
Keywords: French & Italian.

Questo lavoro è uno studio (preparatorio) dei rapporti tra esistenzialismo e letteratura italiana nel Novecento secondo un approccio geo-critico, che mira a indagare i rapporti genetici tra letteratura e filosofia. Nel primo capitolo delineo la metodologia critica adottata nel lavoro e i problemi storico-interpretativi che fino ad oggi hanno impedito una lettura di questo genere, attraverso la costruzione di un modello spaziale che tocca quattro città italiane e i rispettivi autori: Milano (Antonia Pozzi e Vittorio Sereni); Firenze (Mario Luzi, Piero Bigongiari, Alessandro Parronchi); Torino (Cesare Pavese, Italo Calvino, Beppe Fenoglio); Padova (Andrea Zanzotto). Il secondo capitolo, che costituisce il cuore della tesi, è dedicato alla poesia di Pozzi e Sereni, e di come Antonio Banfi, Enzo Paci -- e dunque Husserl, Heidegger e Jaspers -- abbiano formato e influenzato la loro poetica. Attraverso un'analisi testuale, ho cercato di far emergere gli elementi di continuità, discontinuità e di novità tra i poeti e filosofi presi in esame, e quali sono le conseguenze sul piano estetico dell'incontro tra poesia, esistenzialismo, fenomenologia e relazionismo.
Local control of magnetic anisotropy [electronic resource]
Keywords: Applied Physics.

Investigating physical mechanisms to manipulate magnetic anisotropy is important for technological applications. We use a scanning superconducting quantum interference device (SQUID) microscope to image the response of micron-scale magnetism to externally controlled currents, voltages and strains. The first part of this thesis (chapters 2 and 3) focus on the physics behind devices and materials that could replace silicon transistors. Chapter 2 focuses on a proposal for a new magnetic memory device using spin transfer torque from the spin Hall effect to manipulate ferromagnetic insulators. Ultimately, this proposal did not prove to be fruitful because of diverging ferromagnetic damping at low temperatures and lacking studies on the spin transparency between the spin Hall metal and the magnetic insulator. Chapter 3 is about SQUID characterization of a composite multiferroic, which can be the basis for another magnetic memory proposal. These results proved to be inconclusive, and modeling these systems proved to be difficult because of the multi-domain behavior of these films. The second part of this thesis (chapters 4 and 5) focuses on how a common substrate, SrTiO$_3$ (STO) can profoundly affect electronic properties including transport and magnetism. Chapter 4 describes experiments on the conducting interface between band insulators LaAlO$_3$/STO. We examined magnetism in related compounds LaGaO$_3$/STO and NdGaO$_3$/STO, and found that ferromagnetic patches in those systems, like in LaAlO$_3$/STO was very sparse and nearly non-existent. In addition, we measured how electronic transport on a local scale changed with strain, and our results were inconclusive. Finally, Chapter 5 describes how magnetism in EuS, a ferromagnetic insulator that could be used to induce exotic phases like Majorana bound states or chiral edge states, is strongly coupled to the STO substrate. We explore how strain from the STO substrate could affect magnetic anisotropy. This thesis highlights the importance of temperature on controlling magnetic anisotropy for switching experiments and for constructing devices that require homogeneous magnetic exchange.
Long-term decrease in plate coupling prior to the 2011 Tohoku, Japan earthquake [electronic resource] : insights from GPS and seismicity data and physics-based models
Keywords: Geophysics.

Until the turn of the century, studies of crustal deformation had shown that strain around active fault zones, as measured by geodetic techniques, accumulates at a constant rate between large earthquakes. Over the past fifteen years, however, thanks to the rapid growth of continuous geodetic data, mainly using the Global Positioning System (GPS), a variety of transient deformation signals have been discovered. Mostly occurring in subduction zones, these transient events last for several days to a few years and manifest as anomalous deviations from the interseismic strain rate. In this thesis, I present evidence of a much longer-term deformation transient in northern Japan, over the 15-year period from 1996 to 2011, prior to the M 9 Tohoku-Oki earthquake. GPS position time series in the south-central Tohoku region exhibit nonlinear trends from 1996 to 2011, but in the period 2003--2011 the time series are heavily influenced from postseismic transients due to several M ∼ 6--7 earthquakes. In the first part of the thesis, I correct for these effects and quantify the residual change in interseismic strain rate. I find spatially coherent and statistically significant accelerations in the position time series at numerous stations throughout the Tohoku region. These accelerations can be explained by accelerating aseismic creep on the Japan trench plate interface in the decades before the 2011 Tohoku-Oki earthquake. In the second part of the thesis, I show that changes in the recurrence intervals of repeating earthquakes on the megathrust in the period 1996 to 2011 are consistent with accelerating slip preceding the Tohoku-Oki earthquake. All sequences of repeating earthquakes with statistically significant trends in recurrence interval (at 95% confidence) offshore south-central Tohoku occurred at an accelerating rate. Furthermore, estimates of the magnitude of slip acceleration from repeating earthquakes are consistent with the completely independent geodetic estimates. From joint modeling of the GPS and seismicity data, I infer that a substantial portion of the megathrust experienced accelerating slip, partly surrounding the eventual rupture zone of the M 9 earthquake. The inference of long-term accelerating creep challenges the conventional "asperity model" for the Japan Trench megathrust which, before 2011, posited that the fault was partitioned into fixed velocity-weakening patches (asperities) that are locked interseismically and velocity-strengthening regions that creep stably without accumulating stress. In the third part of the thesis, I use physics-based simulations of earthquake cycles with thermal pressurization to develop a physical model for shrinking asperities. This model may provide a viable physical mechanism for this surprising transient.
Loop equations and string dualities in lattice gauge theories [electronic resource]
Keywords: Mathematics.

The purpose of this dissertation is to explore loop equations and string dualities in lattice gauge theories. A lattice gauge theory involves a lattice, a compact Lie group, a matrix representation of the group and a parameter which is called an inverse coupling strength. The main objects of interest in the lattice gauge theories are the Wilson loop variables. A loop equation refers to expressing the expectation of a Wilson loop variable in terms of the expectations of Wilson loop sequences obtained from the loop by various loop operations. These loop equations can be used to establish the 1/N expansion of Wilson loop expectations in a strongly coupled regime. The coefficients of this expansion are represented as absolutely convergent sums over trajectories in a string theory on the lattice, establishing one kind of gauge-string duality. Finally, we will present several applications of this expansion such as the Wilson area law upper bound, the factorization property, and the correspondence of SO(N) and SU(N) Wilson loop expectations in the large N limit.
Low-cost growth of III-V and II-VI semiconductor thin films [electronic resource]
Keywords: Materials Science and Engineering.

This dissertation explores methods to obtain high-quality, low-cost III-V and II-VI semiconductor thin films. Silicon is the predominant semiconductor material of choice for most electronics applications, but non-silicon semiconductors may be more well-suited to certain applications. III-V materials such as GaAs and InP have favorable optoelectronic properties but are currently too expensive to compete in the market. Methods that could separate III-V thin films from their substrates could lower these costs significantly. In the first section InP single-crystal thin films are separated from their substrates with the selective absorption of a short and intense laser pulse, a process called epitaxial laser liftoff. The physical mechanisms driving laser liftoff are explored and compared with GaAs liftoff, and spatially-resolved measurements of the threshold fluence for liftoff and transmitted intensity through a wafer are devised. Conversely, II-VI based semiconductors like Cu2ZnSnSe4 are more defect-tolerant and simpler than silicon to manufacture, but are not efficient enough to be cost-effective. Alloying this material with Cu2ZnGeSe4 could allow for tuning of the properties for improved performance. In the second section Cu2ZnSn(1-x)Ge(x)Se4 thin films in the composition range 0< x< 1 are grown by co-sputtering and reactive annealing. Growth conditions are described that yield single phase films for all values x, tunable band gaps in the range 1.0 to 1.5 eV, or composition gradients through-thickness for band gap grading. The mechanisms for growth and recipe to produce dense thin films with large, faceted grains are also provided.
Low-power coherent optical links for data center interconnects [electronic resource]
Keywords: Electrical Engineering.

Hyperscale data centers built to accommodate variable traffic patterns supporting virtualization and cloud computing are evolving to employ a flatter network topology, comprising fewer layers of switches, but with much more interconnection between them. The requirements of these networks, coupled with expected compound annual growth rates of 32% for data center-to-data center IP traffic in the next five years, necessitate scaling the per-wavelength bit rates of optical links beyond 100 Gb/s while keeping power consumption and cost low. Coherent detection can offer the requisite performance demanded by future intra- and inter-data center links, but current implementations consume too much power and are too costly for optical transceivers needed for future data center networks. In the first part of this dissertation, we address the transmitter side of future coherent optical transceivers by designing and validating silicon-based Mach-Zehnder modulators. We leverage the efficiency of the silicon modulator to configure submillimeter-length coherent modulators that can be driven by low-power CMOS drivers and show that their performance can match existing lithium niobate modulators for coherent transmission. We further leverage the efficiency of the silicon-based modulators by segmenting them and showing that higher-order modulation formats can be generated by driving segmented modulators with only binary signals, precluding the need for expensive and power-hungry linear drivers and digital-to-analog converters. The second part of this dissertation addresses coherent receivers for future optical transceivers. We propose various analog coherent receiver architectures that do not employ the high-speed DSP and analog-to-digital converters that make existing DSP-based coherent receivers power-hungry and costly. Implementing these analog coherent receivers for data center links requires performing functions, such as carrier recovery and polarization demultiplexing, that are typically done using DSP. We propose and simulate a marker tone-based polarization demultiplexing solution using an optical polarization controller consisting of a sequence of phase shifters.
Magnetic effects at complex oxide interfaces [electronic resource]
Keywords: Materials Science and Engineering.

Control, manipulation, and measurement of the spin state of electrons, termed spintronics, has been critical to the development of magnetic memory devices which have dominated non-volatile data storage in computers, servers, and often even media formats. Likewise, performing computational operations using electron spins is under active development to supplement, or in some cases replace, traditional charge based logic. Complex oxides are a powerful tool for spintronics as their strong electron interactions and correlations lead to unique and powerful spin functionality. The myriad interesting phenomena observed in complex oxides, from multiferroics to high Tc superconductors, suggests not only their viability as spintronic materials but also the ability to couple the relevant spin operations to a wide variety of novel functionalities. In this work, complex oxide materials are investigated to explore two spintronics opportunities. The first half of this research attempts to introduce a spin-polarized conducting interface between two diamagnetic, insulating materials. The second half explores spin-pumping behavior in the previously unutilized spinel ferrites. One avenue for the development of spintroincs is the concept of "materials by design" where material properties and functionality are tuned or introduced through their nanostructure or interfaces. A leading example of this paradigm is the LaAlO3/SrTiO3 interface where conductivity is observed between two insulating materials. Magnetic ordering at the interface has been inconsistently observed in previous studies, however generation of a spin-polarized conduction layer on-demand would be extremely useful for spintronic devices. Therefore, this work pursues this emergent spin phenomenon by introducing magnetic dopants at the interface. The system is observed to be electrically and magnetically unaffected by the presence of the dopants however. Furthermore, no evidence for magnetic ordering is observed in undoped LaAlO3/SrTiO3 systems, drawing into question the intrinsic origin of the previously observed magnetic moments. The remainder of this work is devoted to characterizing spin pumping in a previously unexplored class of materials, the spinel ferrites. Here "pure" spin currents, where spin moments are transported without net charge flow, are generated in adjacent metals, and the efficiency is characterized through the spin-mixing conductance at the spinel-ferrite/metal interface. The order-of-magnitude improvement in intrinsic damping and a spin-mixing conductance competitive with literature-leading systems indicate Ni0.65Zn0.35Al0.8Fe1.2O4 to be a viable spin-pumping material. The design parameters of this model system can be extracted to myriad other spinel materials and paves the way for future all-oxide spin-pumping systems.