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A 1.7GS/s SAR ADC in 28nm CMOS
No full textThis thesis presents a 1.7GS/s 9b single channel SAR ADC in 28nm CMOS technology. The main focus of the thesis is the leveraging of the pipelining, passive residue transfer, and partial interleaving techniques to increase sample rate of the ADC. The first chapter explains the motivation for increasing the single channel ADC speed as well as the operation of the SAR ADC and pipelined SAR ADC and their inherent limitations. The second chapter presents the architecture investigated in this project. The third chapter details the circuit level implementation of the ADC. The fourth chapter shows simulation results, and the fifth chapter presents the conclusions.Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2026-02-19 without embargo termsThe student, John Burns, accepted the attached license on 2025-12-12 at 11:47.The student, John Burns, submitted this Thesis for approval on 2025-12-12 at 11:56.This Thesis was approved for publication on 2025-12-12 at 13:07.DSpace SAF Submission Ingestion Package generated from Vireo submission #23150 on 2026-02-19 at 18:30:3
Computational modeling of dynamic phase change materials in thermal energy storage for concentrated solar power
No full textEnergy demand is rapidly growing on a global scale. Population growth, electrification, and the advent of artificial intelligence and other high-power computing functions are among the biggest drivers of this increasing demand. The design and implementation of reliable, modernized power systems such as modular, networked microgrids is essential to meet this growing demand. Thermal energy resources such as parabolic trough concentrated solar power (CSP) are commonly used in microgrids to support thermal power demands, but CSP power production is intermittent. Implementing thermal energy storage to modulate the power output of thermal energy systems can manage intermittence. Power system planning, however, involves uncertainty around the quantitative impact that power resource investments such as concentrated solar power (CSP) and thermal energy storage will have on the reliability and resilience of a microgrid. Conventional latent thermal energy storage technologies have shortcomings, such as migration of the melting front over time. This introduces additional conductive resistance during the charge cycle that negatively impacts heat flux into the energy storage phase change material (PCM). A new conceptual technology called dynamic phase change materials (dynPCMs) have been developed to address this shortcoming by applying mass or piston-based pressure to the solid state of the energy storage PCM to keep close contact between the heated boundary and the solid portion of the PCM as it melts. This technology theoretically improves the performance of thermal energy storage. This study introduces a computational model that calculates metrics for the expected performance of parabolic trough Concentrated Solar Power (CSP) systems with conventional latent thermal energy storage versus dynPCM thermal energy storage. The model includes a control system to modulate the CSP system’s power output and match a power demand profile as closely as possible. This study shows that, while latent thermal energy storage enables the example CSP system to achieve a power availability of 68.6%, dynPCM thermal energy storage enables the CSP system to achieve a higher power availability than latent thermal energy storage—as high as 79.5%. The study also involves a parametric analysis of the factors which influence the power availability of the system. This model is built for incorporation into a larger computational model which we term Analysis of Microgrid Performance, Reliability, and Resilience (AMPeRRe) to evaluate the performance impacts of incorporating CSP systems and thermal energy storage in larger microgrids. The stand-alone model and AMPeRRe will produce actionable analytics for decision-makers to inform their investment decisions around implementing CSP and thermal energy storage in varied applications. The results shown here can enable a better understanding of thermal energy storage-coupled intermittent energy resources that can meet the energy security needs of a growing world.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01The student, Jessica Nicholson, accepted the attached license on 2025-11-14 at 14:33.The student, Jessica Nicholson, submitted this Thesis for approval on 2025-11-14 at 14:57.This Thesis was approved for publication on 2025-11-17 at 14:56.DSpace SAF Submission Ingestion Package generated from Vireo submission #22872 on 2026-02-19 at 18:45:4
“We need to save civilization first”: examining the role of cyberlibertarian design in the disinformation culture of Reddit’s /r/The_Donald
No full textCyberlibertarian design principles have become an increasingly common feature of mainstream social media platforms, with Facebook, YouTube, TikTok, Reddit, and other platforms employing once-experimental models of content moderation that assume a cyberlibertarian stance towards free speech. Seeking to understand the impact of this design politic upon our media landscape, this dissertation explores Reddit’s alt-right subreddit /r/The_Donald, utilizing a framework rooted in both science and technology studies and critical theories of the media. To that end, the dissertation examines the form and content of the subreddit, beginning from its inception in 2015, and culminating with the apex of its prominence in the public consciousness during 2017’s Unite the Right rally. By examining this critical site of development of the online far right within the context of the right-wing media ecosystems from which it emerged, I seek to understand the critical differences between human- and algorithmically-moderated (dis)information flows, their intersection and interaction with far-right subjects, and the impact of their design and affordances upon democratic publics in a time of informational crisis.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01The student, Gabriel Malo, accepted the attached license on 2025-11-21 at 15:53.The student, Gabriel Malo, submitted this Dissertation for approval on 2025-11-21 at 16:01.This Dissertation was approved for publication on 2025-11-24 at 11:33.DSpace SAF Submission Ingestion Package generated from Vireo submission #22925 on 2026-02-19 at 18:45:5
Sequence and structural effects on molecular conductance of bioinspired peptoid oligomers
No full textThe sequence-structure-function paradigm demonstrates that polymer sequence directly impacts the three-dimensional structure, which in turn dictates biological function—principles we can apply to synthetic polymer design. One class of sequence-defined polymer that has made great progress in attaining biology-like control over sequence and structure are peptoids or N-substituted polyglycines. The sequence-defined modularity of peptoids enables precise control over their structure–function relationships, enabling potential materials applications in energy storage, energy conversion, and biomedical technologies. In Chapter 1, I lay the foundations of the motivations behind studying how helical secondary structure affects molecular charge transport in peptoid oligomers.
In Chapter 2, characterizations of electron charge transport in peptoid oligomers uses the scanning tunneling microscopy break-junction (STM-BJ) method build upon previous studies on the effect of sequence and molecular conformation and secondary structure in synthetic organic molecules and peptides on molecular charge transport. Despite recent progress, understanding the role of peptoid sequence and conformation in electron transport has been challenging to study. Here, I synthesize a library of peptoid oligomers and characterize their molecular electronic properties using the scanning tunneling microscope-break junction (STM-BJ) technique. The work in this chapter reveals well-defined electron transport pathways for peptoids lacking secondary structure. In particular, peptoid sequences with aromatic side groups lacking hydrogen bonds and methyl substitutions at the N-Cα position led to well-defined conductance features. This behavior fundamentally differs from electron transport in peptides, where secondary structure derived from hydrogen bonds leads to an enhanced conductance feature compared to peptides with non-helical backbones. All-atom molecular dynamics (MD) simulations are used to understand the conformational heterogeneity of peptoids. The molecular conformations obtained from MD simulations are used in quantum mechanical calculations based on the non-equilibrium Green’s function–density functional theory (NEGF-DFT) formalism, and the results show reasonable qualitative agreement with experiments. Overall, these results reveal new insights into structure-function relationships describing electron transport in peptoid-based electronic materials.
In Chapter 3, we move away from single-molecule studies and investigate the role of sequence and secondary structure on a self-assembled monolayer (SAM) of peptoids. This study specifically focuses on peptoid self-assembled monolayers (SAMs) as a model system that still preserves molecular-level information (sequence, side-chain identity, expected conformation) while introducing intermolecular organization. This allows us to probe how secondary structure and intermolecular packing together influence electronic functionality. I synthesized and characterized a library of rationally designed peptoid oligomers with and without helical nanostructures. SAMs were fabricated, and their film morphology and current voltage relationship was characterized. Film morphology is characterized using atomic force microscopy (AFM) scratching experiments and the charge transport properties of these monolayers are characterized using the eutectic gallium indium alloy (EGaIn) soft contact method where we measure the current voltage relationship.
Chapter 4 outlines future directions including designing in situ probes for monitoring peptoid conformation and studies of charge transport through two-dimensional peptoid nanosheet assemblies.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01The student, Brittany Prempin, accepted the attached license on 2025-11-24 at 13:57.The student, Brittany Prempin, submitted this Dissertation for approval on 2025-11-24 at 14:02.This Dissertation was approved for publication on 2025-11-25 at 11:46.DSpace SAF Submission Ingestion Package generated from Vireo submission #22940 on 2026-02-19 at 18:45:5
Biomaterial tools for modeling endometriosis
No full textEndometriosis is a common gynecological disorder that can cause chronic pain and infertility. To better understand mechanisms of disease etiology and progression, researchers are increasingly turning to model systems. In vivo approaches have notable limitations, including limited ability to model human anatomy-related pathologies and poor translation of therapeutics developed in animal models. This chapter describes the current body of work surrounding the recent emergence of in vitro models of endometriosis. This work aims to describe methods by which researchers can consider specifying their work to stages of disease, lesion location, and interactions that could drive disease progression. This chapter defines a roadmap for the development of more robust and specific models of endometriosis with the goal of realizing translatable therapeutic strategies and non-invasive metrics of disease presence and progression.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01The student, Hannah Theriault, accepted the attached license on 2025-12-01 at 12:43.The student, Hannah Theriault, submitted this Thesis for approval on 2025-12-01 at 13:06.This Thesis was approved for publication on 2025-12-01 at 16:46.DSpace SAF Submission Ingestion Package generated from Vireo submission #22974 on 2026-02-19 at 18:46:0
Perceived barriers and minority stress in college ecosystems as factors of support for LGBTQIA+ students’ utilization of campus resources
No full textThis study aimed to explore how LGBTQIA+ students experience the decision-making process about utilizing campus resources, including sexual misconduct resources. These processes are based how and to what extent they feel their sexual orientation and gender identity play a role in their experiences when deciding to use resources; levels of support throughout their educational ecosystem; and their feelings and attitudes toward the institution regarding support for resource utilization. The study uses Bronfenbrenner’s ecological systems theory model (1979) and the minority stress theory (Meyer, 2003) as frameworks to assess the support experienced by LGBTQIA+ students in their college environments. A mixed methods approach was employed to address the dearth in qualitative data to illuminate a deeper understanding of these students’ lived experiences of support.
The data collected supports the predetermined themes found in the existing literature: barriers to resource utilization, diminishing levels of support, impact of “outness”, and the existence of LGBTQIA+-informed resources. The findings of this study emphasize the need for LGBTQIA+-informed and inclusive resources to better support this population of students on college campuses. Minority stress can be lessened if colleges encourage and improve support for LGBTQIA+ students which leads to a more equitable college environment.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-12-01The student, Victoria Harris-Karnes, accepted the attached license on 2025-12-01 at 11:29.The student, Victoria Harris-Karnes, submitted this Dissertation for approval on 2025-12-01 at 11:38.This Dissertation was approved for publication on 2025-12-01 at 11:57.DSpace SAF Submission Ingestion Package generated from Vireo submission #22994 on 2026-02-19 at 18:46:0
Thermo-optic Phase Spectroscopy techniques for multiscale thermal conductance characterization in semiconductor integrated circuits
No full textThermal management remains a critical challenge in the advancement of semiconductor integrated circuits, particularly with the emergence of three-dimensional (3D) architectures for high-performance applications. This thesis introduces Thermo-optic Phase Spectroscopy (TOPS), a family of non-destructive techniques for multiscale thermal conductance characterization across bulk materials, buried films and interfaces, and nanoscale films.
Three variants are developed: Displacement TOPS (D-TOPS) for bulk solids, Immersion TOPS (I-TOPS) for deeply embedded films and interfaces, and High-Resolution TOPS (HR-TOPS) for nanoscale semiconductor films. Each technique combines AC laser heating, temperature sensing via probe beam deflection, and analytical modeling to extract thermal properties with high spatial resolution, sensitivity, and speed. A unified modeling framework accommodates multilayer structures with anisotropic thermal expansion and elastic constants. Experimental validation demonstrates TOPS’s ability to extract thermal conductivity and thermal boundary conductance with improved accuracy and reduced acquisition time compared to conventional methods.
By enabling precise thermal conductance characterization across multiple scales, TOPS provides essential data for optimizing fabrication processes, improving thermal simulations, and guiding temperature sensor placement in next-generation IC designs.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-12-01The student, Jinchi Sun, accepted the attached license on 2025-10-08 at 23:02.The student, Jinchi Sun, submitted this Dissertation for approval on 2025-10-09 at 08:44.This Dissertation was approved for publication on 2025-10-10 at 09:07.DSpace SAF Submission Ingestion Package generated from Vireo submission #22823 on 2026-02-19 at 20:08:3
I. Reaction mining—a next-generation platform for reaction discovery II. Rapid, anhydrous, homogenous Suzuki-Miyaura cross-coupling of aryl and alkylboronates
No full textHerein, this work informs two distinct areas of research and development on: (1) a reaction discovery platform enabled by the merger of high-throughput experimentation (HTE) and data science, and (2) preparative methods for aryl-aryl and B-alkyl Suzuki-Miyaura cross-coupling of boronic esters and boronates. Chapter 1 describes previous efforts by Sarlah and Shved to accelerate the reaction discovery process with the combination of data science, HTE, and artificial isotope distributions. A workflow was subsequently designed with this strategy and showcased with a multimetallic catalyst screen, resulting in the discovery of a few new reactions. Chapter 2 provides an overview of the Suzuki-Miyaura reaction, with a focus on studies pertaining to its mechanism and its B-alkyl variant. This section includes a description of the pioneering reports by Denmark, where a tremendous rate enhancement was observed for the anhydrous Suzuki-Miyaura cross-coupling of neopentyldiol arylboronic esters with a soluble base, potassium trimethylsilanolate (TMSOK). However, the commercial availability of these organoboron species is poor, rendering the method inaccessible for most practitioners. To address this limitation, in Chapter 3, a rapid one-pot Miyaura borylation/Suzuki-Miyaura cross-coupling of aryl halides that leverages commercially available bis(neopentylglycolato)diboron is described. The TMSOK-promoted cross-coupling conditions reported by Denmark were found to be also applicable to alkylboronic esters, facilitating the discovery of a rapid B-alkyl Suzuki-Miyaura cross-coupling of primary alkylboronic esters, However, the extension of this method to secondary alkylboronic esters resulted in failure, owing to significant protodehalogenation. Mechanistic studies aimed at identifying the origin of this unproductive side reaction revealed that the boronic ester itself was surprisingly the predominant hydride source. After a survey of boronic esters, in collaboration with the Burke lab, tetramethyl N-methyliminodiacetic boronates (BTIDA) were identified as a precursor to a highly reactive boronate species, mitigating protodehalogenation while affording rapid cross-coupling. Compared to previous methods, this advance demonstrates unparalleled generality for both aryl halide and organoboron reaction partners. To highlight this feature, the development of an HTE-informed substrate scope is shown. Moreover, the reaction is highly stereospecific, proceeding with either retention or inversion of configuration depending on the choice of ligand and substrate. Lastly, the identity of the unknown boronate has been determined through structural studies, suggesting RB(OTMS)3 as a likely candidate.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-12-01The student, Matthew Bock, accepted the attached license on 2025-11-14 at 11:17.The student, Matthew Bock, submitted this Dissertation for approval on 2025-11-14 at 11:41.This Dissertation was approved for publication on 2025-11-17 at 15:12.DSpace SAF Submission Ingestion Package generated from Vireo submission #22871 on 2026-02-19 at 20:08:4
Hailstorm events over a maritime tropical region: a study of environments and microphysics of Surabaya hail events, Indonesia
No full textIn recent years, several hail events have been observed in the Maritime Tropics (mT), including five occurrences in the urban area of Surabaya, Indonesia. Past studies of mT hailstorms have been limited to individual case studies and often have restricted accessibility to a general international audience, leading to an under-representation of hail research in this region within global hail studies, even though this type of severe convective storm (SCS) is among the costliest weather events. Therefore, this study is presented to explore in more depth the hailstorm environments in mT regions and their implications for cloud microphysical processes related to hail production.
Using real-case simulations with the Weather Research and Forecasting (WRF) Model, we reproduced ten thunderstorms over Surabaya: five documented hail events and five additional no-hail storms for comparison. We found that common environmental predictors of hail used for mid-latitude SCS events, such as Convective Available Potential Energy (CAPE) and deep-layer bulk shear, were less useful for this region. Consequently, we proposed a new metric for predicting hail environments in maritime tropical areas, namely NetCAPE, which incorporates water-loading correction and accounts for the net values of CAPE and CIN across several atmospheric layers within the defined hail growth zone (HGZ), from freezing level up to –20°C. The median low-level NetCAPE for the five hail events was over 40% greater within various depths of the HGZ. When combined with lower near-surface (surface to 925 hPa) relative humidity and lower melting level heights, it effectively differentiated hail from no-hail cases. We also classified the hail environments based on this metric into three main types, the most common of which are single-cell, pulse-type, and short-lived storms.
We further tested the NetCAPE variable—particularly the value from the surface to the 0°C level, termed NetCAPE0C—to understand why this variable effectively predicts hail environments in these specific mT regions. We conducted idealized simulations using the Cloud Model 1 (CM1) for typical single-cell and pulse-type hailstorms in this environment. In general, we found that as the NetCAPE0C in the simulated environment increased, the maximum hail size near the ground also increased. Our results further show that NetCAPE0C is effective because the layer extending from the surface to the 0°C isotherm encompasses the region where supercooled liquid water content (SLWC) is maximized—typically concentrated near the –5°C isotherm. NetCAPE0C also controls the updraft width and depth, especially in the earlier stages of storm development, where larger values promote quicker raindrop formation and thus accelerate riming and hail growth. In these simulated pulse storms, we also learned that hail growth in this mT region is generally constrained by three mechanisms: (1) the rapid warm-rain process, which, under weaker updrafts, leads to earlier precipitation fallout and reduces the chance for raindrops to be lifted higher and later freeze as hail embryos; (2) an imbalance between updraft strength, abundant SLWC, and a shallow HGZ, which confines most SLWC near the freezing level instead of higher in the HGZ, thereby reducing the vertical distance available for riming and limiting hail size; and (3) relatively simple hail trajectories, which primarily undergo wet growth with abundant shedding while descending just above the 0°C level.
Finally, the results of this study reveal the distinct environmental and microphysical characteristics of hailstorm development specific to mT regions, which differ markedly from those of mid-latitude supercell-type hailstorms. Nonetheless, future work should aim to conduct broader studies, including a climatology of hail events across different areas within mT regions, to assess potential local influences of topography and land use. This would also allow testing whether the proposed NetCAPE metric is robust in predicting hail events across a wider range of storm types and regional environments. Such climatological analyses are expected not only to identify more general and robust environmental predictors but also to investigate how future climate warming, land-use change, and aerosol variations might affect hail occurrence and size in these regions. This effort would ultimately strengthen the understanding and generality of mT hailstorm behavior and address questions that could not be fully answered in the present study.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-12-01The student, Fitria Sari, accepted the attached license on 2025-11-20 at 10:35.The student, Fitria Sari, submitted this Dissertation for approval on 2025-11-20 at 11:01.This Dissertation was approved for publication on 2025-11-24 at 11:44.DSpace SAF Submission Ingestion Package generated from Vireo submission #22910 on 2026-02-19 at 20:08:5
The role of genomic selection and advanced statistical modeling in domesticating perennial sorghum
No full textThe perennialization of agronomically valuable grain crops, such as sorghum (Sorghum bicolor (L.)), has the potential to significantly enhance sustainable agriculture and food security, particularly in regions experiencing soil degradation, water scarcity, and resource limitations. Genomic prediction (GP) is a crucial tool for accelerating the selection process in breeding perennial sorghum for key domestication and perenniality traits.
The goal of the research presented in this dissertation is to assess and implement the most effective GP model for accelerating breeding cycles. This work focused on two key questions. First, are there benefits of incorporating genetic architecture (using multi-kernel) into GP predictive ability? Second, can accounting for Genotype × Environment (GxE) interactions, including the use of environmental covariates (ECs), improve predictive ability?
We found that partitioning single nucleotide polymorphisms (SNPs) based on a priori genetic features did not consistently boost predictive ability when compared to standard genomic best linear unbiased prediction (GBLUP) for these populations. Therefore, we inferred that the added complexity of MultiBLUP is not worth the negligible gains. In our multi-environment studies, we found that simple traits such as flowering time showed high and stable predictive ability. In contrast, perenniality traits were more complex to predict, and including ECs had little effect on improving their predictive ability.
We developed GenSelect, an accessible R Shiny application that implements advanced GP models (GBLUP, MultiBLUP, GxE with and without ECs), allowing practitioners to easily upload their own data and identify the optimal model for their unique accessions. This application makes these models usable and broadens the potential impact of this research.
This dissertation aims to identify the most effective and practical genomic prediction strategies for accelerating the breeding of perennial sorghum. These findings and the GenSelect tool facilitate the development of a practical GP pipeline for perennialized sorghum, guiding future efforts to create environmentally sustainable crops and enhance food security. Future research should focus on obtaining below-ground environmental covariates and collecting data in more diverse environments to boost multi-environment predictive abilities for perenniality traits.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-12-01The student, Sarah Widener, accepted the attached license on 2025-12-03 at 16:50.The student, Sarah Widener, submitted this Dissertation for approval on 2025-12-03 at 16:57.This Dissertation was approved for publication on 2025-12-05 at 08:38.DSpace SAF Submission Ingestion Package generated from Vireo submission #23051 on 2026-02-19 at 20:09:5