VictorJuiz/thesis huggingface dataset:
Nonlinear angles-only orbit estimation for autonomous distributed space systems
Keywords: Aeronautics and Astronautics.

There is a growing interest in future space mission concepts which involve the interaction of multiple satellites, including on-orbit servicing and debris mitigation, space situational awareness, and swarm-based sensing. These so-called distributed space systems place strict requirements on spaceborne relative navigation accuracy and robustness, autonomy in early phases of the mission, scalability to multiple agents, and resource efficiency in order to meet mission specifications. This research rises to these demands by focusing on a mid- to far-range estimation method called angles-only navigation, wherein observer satellites use bearing angles obtained from onboard monocular camera imagery of target space objects to infer the target orbital trajectories. In this context, vision-based estimation is chosen because it provides a passive and high-dynamic-range navigation technology that uses simple, flight-proven, and miniaturization-friendly hardware. However, since a target appears as only a cluster of pixels in the images, estimating its orbital motion with respect to the observer is fundamentally constrained due to a lack of range information and generally results in poor (or even divergent) navigation performance. To overcome this limitation, a novel angles-only navigation architecture is developed which leverages a deep insight into the relative motion dynamics and advanced filtering techniques to capture key nonlinearities in the dynamics and measurement modeling that lead to range disambiguation. Whereas current approaches require repetition of complex maneuver profiles to gain new vantage points on the target for range rectification, the new methods posed here are completely maneuver-free. To address further deficiencies in the current state of the art, the proposed framework generalizes the applicability of angles-only navigation to new domains beyond low Earth orbit, to situations where no prior state knowledge is available for estimator initialization, and to new scenarios involving multiple observers and/or targets. The functionality and performance of the proposed navigation architecture are verified using rigorous software-based and hardware-in-the-loop simulation. Finally, the algorithms developed in this work have led to the systematic design of the Starling Formation-flying Optical eXperiment (StarFOX), which will test angles-only navigation for future deep-space swarms while flying on board NASA's Starling1 technology demonstration formation in 2021
Nonlinear stability analysis of acoustic streaming using the energy method
Keywords:  Energy Resources Engineering
School of Earth Energy &amp; Environmental Sciences
stability analysis
acoustic streaming
energy method
Thesis

Acoustic streaming is recently used in lithium metal batteries to inhibit the formation of dendrites. We review the concepts of hydrodynamic stability and its necessity for finding critical parameters. The energy method is further explored to study the nonlinear stability of outer Rayleigh streaming in a channel. Dimensionless analysis yields a critical parameter in the form of an acoustic Reynolds number and the resulting Euler-Lagrange equations contain nonlinear eigenvalues. The eigenvalue problem is solved numerically and an optimization algorithm is introduced to deal with the nonlinearity. Discontinuities in the domain were handled by solving and matching two models, and energy stability curves were generated for different wave amplitude ratios and channel thicknesses. The obtained critical numbers showed that monotonic stability is maintained longer in thinner channels due to smaller velocities in the base flow. Instabilities are guaranteed to be absent for acoustic Reynolds number less than 259 for thin channels and 0.011 for thick channels. The results proved to be in-line with experimental observations of acoustic flows in batteries. With the provided nonlinear stability thresholds, minimum requirements for instabilities in a channel are better understood.
A nonparametric measure of conditional dependence
Keywords: Statistics.

There are numerous problems where one needs to quantify the dependence between two random variables and how this dependence changes by conditioning on a third random variable. Correlated random variables might become independent when we observe a third random variable or two independent random variables might become dependent after conditioning on the third one. Thanks to the wide potential application range e.g., bioinformatics, economics, psychology, etc, finding efficient measures of conditional dependence has been an active area of research in many subareas of statistics and machine learning. However, the literature on measures of conditional dependence is not so large, especially in the non-parametric setting. We introduce two novel measures of conditional dependence, and propose estimators based on i.i.d. samples. Using these statistics, we devise a new variable selection algorithm, called Feature Ordering by Conditional Independence (FOCI). FOCI is model-free with no tuning parameters and is provably consistent under sparsity assumptions. We provide a number of example application analyses to both synthetic and real datasets
Nonsense and nostalgia in the Lewis Carroll settings of György Ligeti
Keywords: Music.

This dissertation offers a comprehensive investigation of composer György Ligeti's (1923-2006) relationship to the work of Lewis Carroll (1832-98). Drawing on Ligeti's interviews, essays, and archival material, I locate the two Alice books (1865/71) as a node on the composer's biographical web where various strands of his life and music intersect. In parsing his memories of growing up in Transylvania—his "childhood mythos"—I evaluate Ligeti's earliest encounter with Alice's Adventures in Wonderland via a Hungarian translation by Dezső Kosztolányi. His late-life reengagement with Carroll in the six Nonsense Madrigals (1988-93), composed for the British King's Singers sextet, is indicative of a personal and stylistic strain of nostalgia in the composer's late-period oeuvre. Adopting theories on nostalgia set forth by literary scholar Svetlana Boym, I interpret Ligeti's late-life settings of Carroll and his Victorian contemporaries as a response to exile and old age.
No-One Else Was in the Room Where It Happened: A legislative solution to party-switching in Malaysia
Keywords:  Public Policy Program
Stanford University
Humanities and Sciences
Public Policy Program
Malaysia
Commonwealth
anti-defection
party switching
political party
Thesis

The Malaysian political crisis of 2020 threw the country into socio-political and economic chaos and highlighted the danger of party-switching, also known as party defection, to a growing democracy with a parliamentary system. Several countries across the world have sought to stop the threat of party-switching by implementing anti-defection laws. I examine the efficacy of global anti-defection laws, the prevalence of Malaysian party defections and suggest a possible legislative solution for Malaysia.
Novel droplet techniques for integrative single cell analyses
Keywords: Bioengineering.

The last decade has yielded transformative new methods to analyze single cells, revealing new insights into cellular diversity, tissue organization, and organism development. Droplet microfluidics, in particular, has made it possible to characterize single cells by their genome, epigenome, and transcriptome at unprecedented scale. These techniques have given rise to the first cell atlases, catalogs of hundreds of thousands of cells classified by type across tissues, systems, and even whole organisms. However, despite these advances, researchers lack an unbiased, high-throughput means to link cellular phenotype to genotype within the same cell. This capability would allow single cell analyses to move beyond simply characterizing the heterogeneity within systems and toward a more mechanistic understanding of whole-cell regulation. Here I describe the development of a new technology, Droception, that marries the three most powerful single cell analysis techniques — droplet microfluidics, flow cytometry, and next-generation sequencing — to screen and sort cells by complex phenotypes with downstream sequencing. This technology has the potential to expand our mechanistic understanding of rare biological populations, identify novel cell types unresolved by current techniques, and unlock new avenues for single cell multi-omics
Novel methods of organic electrochemical device nanofabrication and characterization
Keywords: Materials Science and Engineering.

Recent advances in the development of organic mixed ionic/electronic conductors (OMIECs) have paved the way for novel applications that harness these materials' ability to effectively transduce ionic fluxes into electronic signals, such as in the fields of biosensors and neural interfaces. With the modulation taking place throughout the bulk of the material, such organic electrochemical devices offer a volumetric advantage over their inorganic counterparts, with high-transconductance operation feasible even at low operating voltages. This unique mode of operation may be exploited by a wide variety of applications, some yet unexplored. However, while some classes of organic semiconductors have seen tremendous success in market realization, such as the multi-billion-dollar OLED industry, integration of OMIEC semiconducting polymers systems into traditional fabrication processes remains a difficult technological challenge. In this work, I lay out novel strategies to allow for the nanofabrication of previously unattainable organic electrochemical devices, as well as the characterization thereof. The first part of this dissertation provides an introductory background to both organic electrochemical materials and devices, as well as nanofabrication, with a third chapter discussing the work done to bridge the gap between the two. In the second part, I turn to focus on specific applications of nanofabricated organic electrochemical devices, first exploring the properties of an organic electrochemical transistor (OECT) comprised of a lithographically patterned semiconducting polymer and a non-aqueous electrolyte. The remainder of the dissertation focuses on utilizing OMIEC materials for acceleration of artificial neural networks, discussing the characterization and fabrication strategies developed for realizing submicron-scale, MHz addressable, fully encapsulated organic ECRAM devices
Novel tools for optical coherence imaging : gold nanoparticle contrast agents and high-resolution pathology registration by optical barcoding
Keywords: Applied Physics.

Biomedical imaging is a vital part of preventative, diagnostic, and therapeutic medical treatment, but there are surprisingly few viable clinical tools at the microscale (1 to 100 microns; from a single to dozens of cells). Optical Coherence Tomography (OCT) is a high speed and portable 3D imaging technology poised to fill this gap. This work develops on two directions that expand the capabilities of OCT imaging and set up the groundwork for new clinical applications. The first is an investigation of gold nanoparticles as contrast agents in the second near-infrared imaging window. We demonstrate that injected gold nanoprisms are highly scattering contrast agents with tune-able scattering resonances which can be used to greatly enhance the sensitivity of OCT-based vascular imaging. Postinjection OCT angiograms reveal 41% and 59% more vasculature compared to control subjects in healthy and melanoma-bearing mouse skin respectively. We then demonstrate a spectral de-mixing model for gold nanoparticles, that allows us to resolve the proportions of up to 3 different gold nanobipyramids within each voxel. With this, we demonstrate the first instance of triplex OCT contrast agent imaging, used to visualize in vivo regional dynamics within a mouse lymphatic network. The second part of this work explores a new data-centric approach to interpreting optical medical images, a task that remains challenging for clinical professionals in spite of high imaging resolution. We have developed a laser-based barcoding technology that allows us to achieve ultra-high resolution registration (down to 25 microns) of OCT images with H&E pathology images. This technology has allowed us to assemble a library of hundreds of OCT-H&E images pairs from human skin samples obtained during Mohs surgery in a dermatology clinic. We then train a generative neural network on the image library and demonstrate the ability to virtually generate realistic H&E images directly from OCT images. This opens the door to an entirely virtual and non-invasive biopsy based on OCT imaging, bypassing the traditionally labor- and time- intensive biopsy procedure
Nowhere to Go: Community-Based Research on Tenant Displacement and Relocation in the San Francisco Bay Area
Keywords: Stanford Urban Studies
San Francisco Bay Area
tenant displacement
tenant protection policy
relocation assistance
community-based research
Thesis

The San Francisco Bay Area housing crisis is among the worst in the nation, with hundreds of thousands of renters facing rapid gentrification and forced displacement. In response, many Bay Area local governments are considering a variety of tenant protection policies and working to compromise amidst stifling political gridlock between tenant and landlord groups over rent stabilization. Research on residential mobility and evictions suggests that forced displacement leads to financial and health consequences and that displaced tenants face barriers to accessing housing due to discrimination and lack of information. However, few studies examine local tenant protection policies besides rent control, leaving policymakers blind to their effects. One such policy, tenant relocation assistance (TRA)—money given from landlords to tenants upon eviction—has become increasingly popular because of its general acceptance from both tenant and landlord groups. This exploratory study evaluates TRA policies in the Bay Area by considering the impacts of displacement on tenants and landlords. Using a community-based research approach, this project partners with local housing and community-based organizations and draws on (1) an overview of all TRA policies in the Bay Area, (2) quantitative analysis of two municipal-level TRA datasets, and (3) 13 semi-structured interviews with tenants and landlords. Main findings show that due to various policy eligibility constraints and unaddressed barriers to relocation, TRA does little to keep displaced tenants in their hometowns or mitigate the consequences of forced displacement. Policy recommendations suggest alternatives to TRA that proactively prevent forced displacement.
Numerical studies of electron-phonon mediated superconductors
Keywords: Physics.

Electron-phonon interactions are ubiquitous in materials and give rise to bipolarons, charge-density wave order, and superconductivity. The Holstein model is a toy model of electrons coupled to phonons and exhibits much of the same low-energy physics observed in real materials. We study the Holstein model in two dimensions in the limit of weak-coupling through many-body perturbation theory to compute and analyze the superconducting and charge-density wave susceptibilities and various spectral properties. These calculations are performed for systems both in and out of equilibrium and make connections with angle-resolved photoemission and time-resolved angle-resolved photoemission spectroscopy. For systems in equilibrium, we discuss the enhancement of superconductivity driven by the renormalization of the phonon propagator and a surprising difference in two common definitions of the dimensionless electron-phonon coupling strength. Out of equilibrium, we simulate a novel method of determining electron-phonon coupling strength by analyzing electron relaxation dynamics and also characterize the Higgs excitation in a \textit{d}-wave superconductor. In the intermediate coupling limit, no perturbative apporoach or general analytic solution exists for the Holstein model. To overcome this challenge, we study the Holstein model using determinantal quantum Monte Carlo which provides a numerically exact and unbiased method to explore the superconducting and charge-density wave tendencies across a wide range of the phase diagram. We find that superconductivity is optimized at intermediate electron densities and intermediate coupling strength and the strength of the superconducting tendency monotonically increases with phonon frequency
Of Dinners and Diplomacy: What White House State Dinners Reveal About Relationship Building and Goodwill Signaling in U.S. Foreign Policy
Keywords: Program in International Relations
International Relations
White House State Dinners
Diplomacy
Interpersonal Relationships
Goodwill
Gerald Ford
Jimmy Carter
Ronald Reagan
Thesis

Behind their glamour, White House State Dinners are innately political events that put the U.S. president face-to-face with a foreign counterpart for an evening of food and entertainment, usually followed or preceded by days of bilateral meetings. This thesis explores how these Dinners fit into presidents’ diplomatic toolbox by asking How do White House State Dinners relate to U.S. Foreign Policy? It answers this question by quantitatively examining the characteristics of international states invited to Dinners since the first one in 1874 through President Obama's last Dinner in 2016. It then offers in-depth case studies of the Dinners hosted under Presidents Ford, Carter, and Reagan to further illuminate why Dinners occur. This thesis finds that Dinners are used as signals and as mechanisms to improve leaders' interpersonal relationships. It further concludes that the United States invites states to Dinners to endorse U.S.-oriented behavior, to build regional influence, to maintain traditional relationships, and/or to celebrate diplomatic breakthroughs.
On Late Tanizaki Jun’ichirō: Transcription, Authorial Discontent, and Creative Revival
Keywords:  Stanford Global Studies
Modern Japanese Literature
Tanizaki Junichiro
1959-1963
Late Style
Transcription
Irony
Allegory
Freud
Paul de Man
Subjectivity
Thesis

Researchers have long presented Tanizaki Jun'ichirō’s (1886-1965) late works as a trilogy: Kasanka Manganmizuno Yume (1955), The Key (1957), and Diary of a Mad Old Man (1961). They selected these three works for a thematical continuity (in a Freudian term) – personal probation of his late-year existential problems through infantile sexuality in contrast with the genital sexuality observed in his earlier works. This observation, however, overshadows a critical transition of Tanizaki’s writing technique in 1959, the year he started to have his works dictated due to neuralgia. In particular, this study focuses on Diary of an Old Man (1961) and The Maids (1962-1963), the last two novels published before his death in 1965, to examine a stylistic transition influenced by the transcription process after 1959. This paper argues that accepting transcription as writing involving two people meant to be a disillusioning loss of masculine control over his text and thus his belief in literature as art for individual cultivation. This sense of loss was represented in the multi-layered ironic device in Diary of a Mad Old Man. In contrast, the succeeding novel, The Maids, stylistically overturned the extreme ironic device in The Key to demonstrate a masochistic reception and utilization of his late-year biological dilemma. In general, this close investigation aims to complicate the previously constructed understanding of Tanizaki’s late style and to illustrate Tanizaki’s way out of the old-age disabilities and its impact on creation itself.
On linking of lagrangians in symplectic 4-manifolds
Keywords: Mathematics.

In this thesis, we study certain questions related to linking of Lagrangian submanifolds in symplectic 4-manifolds. In Chapter 2, we study linking of Lagrangian tori in R^4. Our main contribution is to prove that the linking properties of Lagrangian tori are closely connected to their enumerative geometry. As an application, we prove that any pair of monotone Clifford tori in R^4 (of possibly different monotonicity constant) are unlinked in an appropriate sense. The analogous result is false for Chekanov tori. In Chapter 3, which is joint work with Georgios Dimitroglou Rizell, we study linking of Lagrangian tori in T*T^2 and in certain rational symplectic 4-manifolds. We discuss various applications; in particular, we exhibit examples of pairs of totally real tori K_1, K_2 \subset T^2 − 0_{T^2} , each of which is isotopic to the zero section through totally real tori, but such that K_1 \cup K_2 is not smoothly isotopic to a Lagrangian. In chapter 4, which is also joint work with Georgios Dimitroglou Rizell, we study symplectic rigidity of cotangent fibers in open Riemann surfaces. This chapter can be seen as a generalization of the celebrated work of Eliashberg-Polterovich proving the Nearby Lagrangian Conjecture for T*R^2. As a corollary, we answer a strong form of a question of Eliashberg that was previously answered in dimensions at least 8 by Ekholm and Smith
On Pre-Colonial Arab Queerness; Abu Nuwas's Homoeroticism as a Site of Investigation
Keywords: Arab Queerness
Comparative Studies in Race and Ethnicity
School of Humanities and Sciences
Joseph Massad
Abu Nuwas
Poetry
Queer
Sexuality
Comparative Literature
Jasbir Puar
Edward Said
Michael Foucault
Thesis

Arab notions of sexuality are rich with literary and aesthetic explorations and representations, particularly as they exist in male same-sex romantic and sexual relations. Among such representations, and of the earliest that exist, is the homoerotic collection of poetry, Ghazal, written by the classical Abbasid period Arab poet Abu Nuwas al-Ḥasan ibn Hānī al-Ḥakamī, otherwise known as Abu Nuwas. In the 21st century, Arab Queer representations and explorations slowly migrated into other mediums of aesthetic representation, including and mostly in autobiographical novels. These include, as pertinent to the research paper at hand, Saleem Haddad’s Guapa, Mohammed Abdel Nabi’s In The Spider’s Room, and Abdellah Taïa’s Salvation Army. Recognizing this aesthetic migration, representations of homoeroticism in Abu Nuwas’s poetry might not only offer a site of investigation for a pre-colonial Arab Queer experience that is separate from Western definitions of Queerness rooted in the Gay Liberation movement of the 1960s, but might also carry forward in modern conceptions of Arab Queerness, as can be traced in the three autobiographical novels earlier mentioned.