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Compartmental Disaggregation: Bridging Simulation and Sampling Methods for Synthetic Population Data Generation
Full text linkAs agent-based models (ABMs) grow increasingly widespread in public health, their associated challenges have become all the more significant. Lauded for their ability to capture population heterogeneity, nonlinear dynamics, and emergent behaviors, disease ABMs are also computationally expensive and often require detailed inputs that describe each agent at the individual-level, known as synthetic population data. Current approaches for synthetic population data generation generally fall into one of two categories: sampling or simulation. These methods are both feasible only under restricted conditions and suffer from challenges surrounding data availability and computing power. This thesis proposes compartmental disaggregation, an intermediate method for producing synthetic, individual-level time series data. By combining population-level measurements with a compartmental model that imposes assumptions about how individuals transition between a set of states, we can recover synthetic data at the individual-level. These data obey the mechanics of a given dynamic process and individual-level data in aggregate match the population-level measurement data by construction. The synthetic population data generated by compartmental disaggregation were found to effectively recover unobserved states from various simulation studies using a classical susceptible-infected-recovered (SIR) model. Applications of compartmental disaggregation will be discussed and include the construction of epidemiological profiles and network inference
Partially Supervised Reinforcement Learning for GPS-Denied Navigation
Full text linkNavigating dynamic environments is a key challenge for autonomous agents, yet most existing research focuses on 3D settings or settings where the agent has full access to relevant semantics. In this work, we propose a learning framework for aerial navigation in the presence of changing dynamics and limited positional information. Specifically, we consider a drone navigation task where a drone at one time has access to GPS location information, which it has now lost and needs to navigate in the same area but at a future time with no GPS signal and differing transition dynamics. To address this, we introduce a novel simulator and algorithm for navigation that provides a similarity map of the agent\u27s position compared to a previously taken reference map of the area. This, combined with other state information, is fed to a feature extractor to calculate a map of the agent\u27s estimated position. The position estimate is provided to a policy network, allowing the agent to navigate. We show how the locational information can be useful for understanding the agent\u27s current perception of its environment and show interesting emergent behaviors of the agent. Our results underscore the importance of robust, sample-efficient learning methods for real-world scenarios where the environment evolves over time and precise localization cannot be assumed
America is Banking on You! Selling American Ideology During World War II
Full text linkThis essay uncovers advertising from World War II found in tear sheet archives. Through deep reading and contextual analysis, this essay seeks to determine what these advertisements—found in magazines, newspapers, and posters—were asking their viewers to do in response to the global conflict of the 1940s. It argues that advertisers used emotions and racism to entice citizens of specific classes to invest, enlist, and align their values with American ideals. The creators of these advertisements were hired by American companies, who used government sponsored tactics to woo citizens to the American Ideology while keeping the corporate brand in the public eye. Ultimately the paper exposes the self-serving nature of these American War advtisements and their impact upon visual culture
Weep No More, My Lady (Oh! Weep No More Today): Love, Violence, Printmaking, and Kentuckian Futurity
Full text linkSituated within a regressive political climate, this essay considers the writer’s thesis artwork Weep No More, My Lady as a simultaneous account of Southern gendered violence and a desire for healing. Through personal and historical connections to Kentucky’s material culture, the work navigates binaries of class, race, and gender that have dictated the dominant contemporary conception of the region. Placing the competing forces of care and brutality in dialogue, Weep No More, My Lady translates these theoretical challenges into formal attributes. The work suggests modes of making — stitching, unraveling, tearing — can act against the construction and naturalization of hierarchy in the United States. Similarly, its use of printmaking mirrors historical discourse, since printmaking is both archival and able to meaningfully break from its own repetitive precedent. Therefore, Weep No More, My Lady attempts to reconcile a harmful past with sentimental longing, seeing a way forward in the process
Measuring Income and Income Inequality
Full text linkIncome inequality is important, but attempts to measure it arrive at strikingly different conclusions. Why? We use recent disputes over measuring United States income inequality to return to first principles about both the income concept and inequality measurement. We emphasize two broad points. First, no measure of the income distribution is truly comprehensive, or could attempt to be comprehensive without making controversial choices. We document the practical and conceptual problems that the standard ideal—comprehensive Haig-Simons income—raises. Second, much of the controversy in this area turns on the many tradeoffs between starting with individual tax data versus more expansive income concepts. Individual tax data reflect only a shrinking subset of a more comprehensive income concept--but they are individual data. More expansive alternatives, on the other hand, are harder to allocate to individuals. We document some of the most important and contestable assumptions that such an allocation requires
Review of mechanoreceptors and the neural processing of touch sensations
Full text linkThis report provides an overview of mechanoreceptors and their role in the somatosensory system, emphasizing their structural characteristics, response properties, and functional specialization. Four major types of mechanoreceptors—Pacinian corpuscles, Meissner’s corpuscles, Merkel’s disks, and Ruffini endings—are described. The report includes the neural pathways from the skin to the brain, focusing on the dorsal column–medial lemniscus pathway and its precise somatotopic organization. Cortical processing in the primary and secondary somatosensory cortices is discussed, alongside competing models of serial and parallel tactile information flow
Tire Modeling and Data Analysis in the FSAE Context
Full text linkAn understanding of tire behavior is crucial to designing a Formula SAE racecar. What variables affect a tire’s performance? How can complex behaviors be modeled mathematically and evaluated with a computer? In this study, data for the Hoosier 16” x 7.5 – 10 R20 tire was analyzed and fit to a Pacejka Magic Formula model, then compared to the WashU Formula SAE team’s current tire (Hoosier 18” x 7.5 – 10) to evaluate the feasibility of switching to a smaller diameter tire. Possible advantages include significant weight savings and a reduction in rotational inertia; however, many other aspects of the tire must be scrutinized. This study focused on overcoming a particular barrier to this analysis: data for the longitudinal performance of 16” tires is not available. Thus, two strategies for estimating the 16” longitudinal behavior were explored: 1) predicting Magic Formula model parameters by training an algorithm on other complete models, and 2) predicting 16” test data by interpolating spline fits of other tires’ test data. Neither method yielded satisfactory estimations, but progress was made toward more efficient model fitting, and new insights for evaluating 16” tires were uncovered. A preliminary analysis of 16” lateral performance data found that the Hoosier 16 x 7.5 – 10 R20 exhibits significant tradeoffs in driving response and maximum grip compared to the team’s current tire. Beyond this study, next steps include incorporating the Magic Formula models into vehicle dynamics simulations, and ideally, doing physical on-car testing
Financial Facts: SEED OK Child Development Accounts at Age 17
Full text linkThe SEED for Oklahoma Kids experiment (SEED OK) is a longitudinal, randomized test a statewide Child Development Account (CDA) policy. The essential feature of the CDA in SEED OK is a state-owned Oklahoma 529 College Savings Plan account, which was automatically opened for newborns in late 2007 with an initial deposit of $1,000. That sum has grown over time, and this Fact Sheet presents financial outcomes as of December 31, 2024, when children in the experiment were 17 years old
The Impacts of the St. Louis Guaranteed Basic Income Program on Economic Security
No full textHow does guaranteed basic income influence the economic security of recipients?
In late 2023, the City of St Louis launched a pilot program providing $500 a month for 18 months to more than 500 low-income St. Louis households with children. Researchers from the Center for Social Development and the Brown School Evaluation Center conducted a mixed-methods evaluation of the program, tracking recipients’ journeys over the pilot’s duration. This brief presents findings on the effects of the St. Louis Guaranteed Basic Income Program on the economic security of program participants, including their experience of economic hardships, their use of the payments, their financial goals, and their overall financial well-being
Open Fiber Fabry–Pérot Microcavities Enabled by CO₂-Laser-Fabricated Concave Mirrors
No full textOpen-fiber Fabry–Pérot microcavities provide a compact and versatile platform for enhancing light–matter interaction, yet their practical deployment is often limited by fabrication complexity, alignment sensitivity, and environmental instability. This thesis presents the design, fabrication, and experimental characterization of open-fiber Fabry–Pérot microcavities based on CO₂-laser-fabricated concave mirrors formed directly on single-mode fiber end faces.
Using a pulsed CO₂ laser micromachining process, concave micro-mirrors with radii of curvature around 160 µm and sub-nanometer surface roughness were reproducibly fabricated without lithographic processing or cleanroom facilities. Gaussian-beam analysis and numerical simulations guided cavity geometry selection, established mode-confinement criteria, and evaluated diffraction loss as a function of cavity length and mirror aperture. Both asymmetric plane–concave and symmetric concave–concave configurations were analyzed, with the latter shown to support robust single-mode operation over extended cavity lengths at telecommunication wavelengths.
Open-fiber cavities were assembled and characterized using reflection-based resonance measurements. Free spectral range, resonance linewidth, finesse, and quality factor were extracted through quasi-static piezoelectric scanning. The measured finesse is found to be close to the coating-limited value set by the mirror reflectivities, demonstrating stable cavity operation and quantitatively consistent agreement with theory. These results establish a complete experimental workflow linking mirror fabrication, optical design, and cavity-level performance.
Beyond fabrication and static characterization, this work positions open-fiber microcavities as a flexible experimental platform for probing dynamic cavity phenomena. The sensitivity of cavity resonances to thermally driven fluctuations motivates future studies of Brownian motion in liquid environments, while dielectric mirror coatings are identified as a key tool for engineering cavity response and enhancing optical sensitivity. Together, these results lay the groundwork for compact, robust, and application-oriented fiber-based cavity systems for precision sensing and mesoscopic photonics