VictorJuiz/thesis huggingface dataset:
Seeing the Edges: How Art Museums Access the Educational Values of Storage Objects
Keywords: arts education
museum education
museum storage
museum educators
informal learning
Graduate School of Education Honors Thesis Stanford University
Thesis

This undergraduate honors thesis explores how education officers at American art museums seek to provide visitors with meaningful experiences that access the educational values of their storage collection. How do art museums tap into the educational value of the objects and artifacts kept in storage to provide the meaningful learning experiences for visitors? To whom do museums provide these experiences? Where are these storage interactions taking place and what values do they have, if any, that are different from gallery experiences? Where is there general agreement among museum educators and where do their perceptions differ? These questions are addressed, through interviews, by educators at 8 different art museums that represent a diverse range of size, visitor demographic, collection type, and location on the East and West coasts of the U.S. I present results that discuss the two types of storage experiences museums are providing: Formal Interactions and Informal Interactions; their values, including increased object visibility, new contexts and new questions, and personal connections; their challenges in preserving the objects and preserving the preciousness of the storage experience; and the counter-narratives that present different perspectives on opening access to storage. This research fills a current gap in our understanding of museum learning while opening and encouraging a conversation among museum educators.
Seeking justice in the courtroom and beyond [electronic resource] : confronting mass atrocity in law and literature
Keywords: Comparative Literature.

Seeking Justice takes as its starting point the growing prominence of legal mechanisms in censuring war and conflict related atrocities. It considers 1945 and the establishment of the International Military Tribunal in Nuremberg as a watershed moment that ushered in a new era in humanity's quest for post-atrocity justice. The historic decision, however, did not end the search for justice. Attempting to balance the scales of justice, legal institutions faced a crisis of incommensurability between the extraordinary crimes and basic elements of ordinary legal justice -- the goals of the process, especially retribution, its procedural form, and its resolution in a final judgment. In the process of overcoming these challenges of incommensurability, legal institutions -- the Nuremberg tribunal, the Israeli Court in the Eichmann trial and the South African Truth and Reconciliation Commission - imagined anew what justice is and should be in the aftermath of atrocity. Producing new notions of justice: enlightenment as justice, narrative as justice, and storytelling as justice, these institutions highlighted some aspects of justice, while marginalizing others. Stepping beyond the boundaries of the legal field, Seeking Justice examines cultural narratives that react - directly or explicitly - to the work of legal mechanisms of justice. The turn to the literary, from journalistic reports on legal proceedings to novels, plays, and films that fictionally engage with the pursuit of justice, my work sheds light on those elements of justice that remain absent, unaccounted for or marginalized in process of metaphorization: the desire for revenge, the dangers of omniscient narrative about the past, and the longing for conclusion and resolution. Bringing together the legal and the literary, Seeking Justice explores humanity's deep belief or desire to believe in the possibility of delivering justice in the aftermath of atrocity and the ongoing challenges it must face as it confronts extraordinary crimes in the courtroom and beyond.
Seismic wave velocity and attenuation in rocks with mesoscopic-scale heterogeneity [electronic resource]
Keywords: Geophysics.

This dissertation describes theoretical developments, numerical simulations, and a field case study on the effect of mesoscopic-scale medium heterogeneity on seismic velocity and attenuation. We focus on the relationship between the wave properties and water saturation. There are three approaches for the study of the effect mesoscale heterogeneity: regular geometry models, branching approaches, and statistical approaches. We develop a hybrid model providing velocity dispersion and attenuation in partially saturated rocks based on the last approach. It will be called Bounds-Averaged Dynamic-Equivalent-Medium Approach (BA-DEMA) and the variable characteristic length model. The developed model has advantages of both the branching and the statistical approaches; it has the appropriate low and high frequency limits; it has an analytical interpolation function which gives appropriate frequency dependence both in low and high frequency regimes, the interpolation function is defined with measurable parameters; and most of all, the mathematical expression is quite simple. These features are the advantages of the new model that would be enough to be recommended for the future use to predict seismic velocity and attenuation in multiphase-fluid saturated media. Forward seismic modeling is an inevitable step to connect rock's properties and their spatial distribution with observable seismic signatures. We describe a practical workflow to evaluate the effects of wave-induced fluid flow. It will serve as a practical guide in forward seismic attenuation modeling. Compared to classical forward seismic modeling procedures, two additional steps are required in attenuation modeling: permeability modeling and estimating dry rock heterogeneity scale. Many authors are trying to develop sophisticated algorithms to extract reliable attenuation information, and broad band seismic data is increasingly available even in exploration projects. The quantitative use of attenuation information derived from surface reflection seismic data is still quite challenging; however, it will become reality in the near future, where forward attenuation modeling discussed in this dissertation will become important. Not only surface reflection seismic but also other techniques such as vertical seismic profile or cross-well seismic profile are utilized to infer subsurface elastic properties and provide the useful information across a target reservoir or the overburden. The latter techniques use high frequency seismic pulse and transmitted waves, which are preferable in attenuation studies and open the possibility of extracting attenuation information more accurately. Recently, attenuation of full-waveform sonic data is also attracting attention. Procedures for the forward attenuation modeling shown in this dissertation can also help the analyses and the interpretations of the different seismic surveys.
Seismological constraints on the mechanics of intermediate-depth earthquakes in the Bucaramanga Nest [electronic resource]
Keywords: Geophysics.

For all the progress that seismology has made in the last century, intermediate-depth earthquakes are a relatively poorly understood phenomenon. They occur at depths 50-300 km, where high temperatures and pressures prohibit traditional brittle shear failure. Intermediate-depth earthquakes frequently occur in concentrated regions of seismicity called "earthquake nests". One such nest, the Bucaramanga Nest, beneath northern Colombia, is the focus of this work. It is the smallest and densest cluster of intermediate-depth seismicity in the world. This clustered region of seismicity produces thousands of events each year. While the nest does not pose the hazard other intermediate-depth earthquake nests might (e.g. the Vrancea Nest, Romania), the nest is capable of producing moderate shaking such as in the M 6.2 event that occurred in the nest in early 2015. This high level of seismicity provides an opportunity to study characteristics of the nest and its earthquakes as a natural laboratory. This dissertation utilizes the tools of observational seismology to expand on processes of intermediate-depth seismicity with particular emphasis on constraining the underlying failure mechanism. To maximize the observations of nest seismicity, I develop a new and novel earthquake detection method that bridges the gap between general and specific earthquake detection algorithms. Through observations of these events, I find repeating and reverse-polarity repeating signals and explain how the timing and relative locations of these earthquakes are indicative of subduction processes at intermediate-depths. I am also able to perform a comprehensive search for small magnitude earthquakes and find the Bucaramanga Nest deviates from traditional Gutenberg-Richter magnitude-frequency distributions at the small end magnitude of the magnitude spectrum. I find multiple lines of evidence that support a thermal shear instability failure mechanism for these intermediate-depth nest earthquakes.
Selective inference and learning mixed graphical models [electronic resource]
Keywords: Computational and Mathematical Engineering.

This thesis studies two problems in modern statistics. First, we study selective inference, or inference for hypothesis that are chosen after looking at the data. The motiving application is inference for regression coefficients selected by the lasso. We present the Condition-on-Selection method that allows for valid selective inference, and study its application to the lasso, and several other selection algorithms. In the second part, we consider the problem of learning the structure of a pairwise graphical model over continuous and discrete variables. We present a new pairwise model for graphical models with both continuous and discrete variables that is amenable to structure learning. In previous work, authors have considered structure learning of Gaussian graphical models and structure learning of discrete models. Our approach is a natural generalization of these two lines of work to the mixed case. The penalization scheme involves a novel symmetric use of the group-lasso norm and follows naturally from a particular parametrization of the model. We provide conditions under which our estimator is model selection consistent in the high-dimensional regime.
Selective inhibitors of the plasmodium proteasome as novel anti-malaria agents [electronic resource]
Keywords: Chemical and Systems Biology.

Malaria, a disease that affects millions of people in the world, is caused by the parasitic protozoan Plasmodium spp. In particular, Plasmodium falciparum leads to the most severe form of malaria and is especially lethal to young children. Although current anti-malaria medications are effective chemotherapeutics, the parasite can rapidly develop resistance to these agents and cases of resistance to even the first line of anti-malaria treatments have been reported. This increases the urgency to identify new malaria drugs and drug targets. In this thesis, I will first describe our efforts at identifying epoxyketone proteasome inhibitors that can attenuate Plasmodium growth with overall low host toxicity. We then synthesized activity based probes to monitor Plasmodium proteasome activity and together with subunit selective proteasome inhibitors, we assessed the importance of individual catalytic sites of the proteasome for parasite survival. We then screened covalent and non-covalent inhibitors against the catalytic site most crucial for parasite viability. Finally, we profiled the substrate cleavage signature of the P. falciparum proteasome and compared it to the human proteasome. We designed peptidic inhibitors based on dominant amino acid residues in the cleavages unique to P. falciparum proteasome. The inhibitor studies, along with cryo-electronmicroscopy structural elucidation of inhibitor bound Plasmodium proteasome, led us to the finding that the host and parasite [beta] 2 proteasome subunit have major differences in their substrate binding site. We then demonstrated how this difference could be exploited for design of potent and parasite selective proteasome inhibitor that was safely dosed in vivo. Taken together, this suggests that the Plasmodium proteasome is sufficiently different from the human proteasome for selective inhibition and promises to be an effective target for anti-malarial therapy.
Self-pressurizing propellant tank dynamics [electronic resource]
Keywords: Aeronautics and Astronautics.

Hybrid rockets frequently use nitrous oxide as a self-pressurizing oxidizer, where the high vapor pressure of the oxidizer is used to force the liquid out of the propellant tank and into the combustion chamber. To study this system, a series of small-scale pressure vessels with optical access have been developed that can be filled with nitrous oxide and then drained in a manner that replicates the conditions within a hybrid rocket. A high-speed camera has been used to visualize the nitrous oxide within the propellant tank and identify relevant phenomena. Experiments have identified two separate temporal regimes that are common to all blowdown tests: a transient and steady state, each described by distinct features. The transient regime is characterized by a rapid pressure drop and recovery, with homogeneous condensation of the ullage and heterogeneous nucleation and growth of bubbles. During steady state regime the liquid and vapor are both homogeneous two-phase mixtures and the pressure drops in a linear fashion as the liquid drains from the tank. Carbon dioxide was identified as a possible simulant fluid for nitrous oxide, and comparison tests showed that it behaves as an accurate analog. This low-cost and safe simulant fluid enabled a large number of tests that examined the effect of parameter variations, including flow rate, fill level, temperature, and scaling effects. Experimental data from this system have been used to develop a new model for self-pressurizing propellant tank dynamics. This was done by blending the 0-D lumped-node methods of previous researchers with a novel 1-D method that captures the dynamics of a changing bubble population. The direct quadrature method of moments was used to develop partial differential equations for parameters of this distribution. The proposed model was compared against experimental data and shown to have good agreement. The pressure drop and recovery seen in the transient regime, which is not captured by previous models, is visible in the model predictions. Convergence studies were performed in order to determine suitable parameters of the numerical integration schemes and the discretizations used. To complete the model, numerous submodels were incorporated by using relations from various sources in the literature. The effect of variations in these submodels was studied in order to justify the selection of adjustable constants.
Sensory substitution and augmentation of forces and torques using tactile skin deformation feedback [electronic resource]
Keywords: Mechanical Engineering.

Haptic devices aim to render a realistic sense of touch using kinesthetic and tactile feedback. Kinesthetic feedback provides forces and torques that affect the motion of the user's hand or arm. Tactile feedback stimulates cutaneous receptors in the user's skin. Currently, most commercial haptic devices aim to provide kinesthetic feedback. Although kinesthetic feedback can convey multiple degree-of-freedom information intuitively to the user, this type of feedback can potentially be destabilizing. In contrast, tactile feedback can be used to create the perception of forces and torques without physically imparting these forces and torques to the user, and is not destabilizing. However, conveying multi-degree-of-freedom force and torque information via the tactile channel, in a manner that is intuitive to a human user, can be challenging. This thesis focuses on the design, development, and experimental validation of a class of tactile feedback devices that provide feedback using local fingerpad skin deformation. Fingerpad skin deformation occurs in our daily interaction with objects, feels natural, and can intuitively express many degrees-of-freedom. Skin deformation tactile feedback can provide force and torque information through skin deformation cues on multiple fingers in a manner that is consistent with our interaction with external objects. This thesis describes several novel skin deformation feedback devices and shows in human participant studies that skin deformation feedback influences perception of stiffness. Skin deformation feedback can be used in conjunction with force feedback to improve the perception of stiffness of virtual surfaces, and can also be employed for sensory substitution and augmentation of force and/or torque information during manipulation of objects in virtual environment or teleoperation scenarios. When skin deformation feedback was used as a form of sensory substitution to convey force/torque information, study participants improved task performance compared to when no feedback was given. When skin deformation feedback was used to augment kinesthetic feedback to provide additional force/torque information, subject participants showed improvements in task performance compared to only kinesthetic feedback. The results of this thesis show that skin deformation tactile feedback is intuitive, and can be used to convey force and torque information to substitute, or augment, kinesthetic feedback. Skin deformation tactile feedback is potentially useful in scenarios where the provision of kinesthetic force and/or torque feedback is difficult, notably in teleoperated robot-assisted surgery, space and underwater teleoperation, where kinesthetic feedback may cause system instability.
The separation and imaging of continuously recorded seismic data [electronic resource]
Keywords: Geophysics.

Imaging targets for exploration seismology surveys are increasingly associated with subsurface conditions that pose serious challenges for both seismic model building and imaging. In particular, these zones of interest are often sub-salt, and can feature dipping, anisotropic overburdens. In order to construct representative Earth models, and hence an accurate image, reflection datasets with large offsets, high levels of reflection point redundancy, and rich azimuthal coverage are sought. This creates a requirement for denser and more efficient field acquisition techniques, which can be achieved through blended data acquisition. Here, multiple source points are acquired simultaneously and receivers continuously record the overlapping wavefields. Separating these simultaneously acquired seismic data into their conventionally acquired equivalent is the link between more efficient data acquisition and conventional imaging and model building techniques. The focus of this thesis is the development of a robust methodology for taking these continuously recorded, blended datasets and accurately separating each shot into an individual record, free from blending contamination. Successful existing techniques unanimously feature strict requirements on the randomness of the source distribution during acquisition, as a consequence, a technique which can separate data with repeatable delay patterns is demonstrated. By using extended seismic migration and inverse forward modeling, separation is demonstrated which is less sensitive to shooting pattern. The image space has several features amenable to the separation problem; it is of lower dimensionality, it has a higher signal-to-noise ratio and methods such as preconditioning and regularization can be employed. Images with a reduced quantity of interference-related noise are created, then a forward modeling process provides a separated output dataset. While forward modeling alone provides a high level of separation, amplitudes subleties of these input data can be lost. By posing the data recovery process as an inverse problem, representative amplitude character is recovered. Posing the problem in the extended image space relaxes requirements on the accuracy of the migration velocity model. This extended space preserves all kinematic and amplitude information present in the input data, and there is no loss of information during imaging. This methodology is demonstrated on three synthetic datasets, of varying complexity, and a 3D Ocean Bottom Node dataset. Qualitative and quantitative comparisons for the synthetic tests show the separation is accurate to the order of 5% after ten iterations. Qualitative analysis of the OBN separation shows that comparable images are achieved after separation, compared to an unblended input dataset.
Shape optimization in adaptive search spaces [electronic resource]
Keywords: Aeronautics and Astronautics.

Design space dimensionality is a persistent obstacle to high-fidelity aerodynamic shape optimization. The burden typically falls to the designer to select the shape design variables, which restricts the design space and impacts computational efficiency. In this work, I develop a system that automatically adapts the shape parameterization to efficiently solve the given design problem. Optimization begins with a small set of design variables, which is then progressively refined to enable the discovery of superior designs. The adaptation is goal-oriented and is driven by a novel refinement indicator that focuses shape control resolution on regions with the highest potential to improve the design. This indicator is computed from adjoint sensitivity information and a quasi-Newton Hessian approximation, which are both readily available in many design frameworks. To verify that the system can autonomously discover parameters sufficient to solve a problem, three inverse design problems are examined. For these cases, the procedure robustly converges to the continuous optimum from different starting points and with different refinement strategies. Several airfoil and wing shape optimization problems are then performed. The adaptive approach generally yields smoother design trajectories, at substantially lower cost than under fixed or uniformly-refined parameterizations. Finally, I consider the combinatorial problem of finding an optimal layout for an adaptive, trailing edge flap system. In fewer than 100 simulations, the adaptive procedure discovers a flap layout that outperforms naive layouts. I conclude with a discussion of the tremendous potential this approach offers for many other disciplines and design environments.