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USING COMMUNITY ENGAGEMENT TO ADAPT ANXIETY COGNITIVE BEHAVIORAL THERAPY FOR AUTISTIC YOUTH RECEIVING SERVICES IN COMMUNITY-BASED ORGANIZATIONS
No full textThesis (Ph.D.)--Michigan State University. Psychology - Doctor of Philosophy, 2025Anxiety disorders are among the most common co-occurring mental health conditions experienced by autistic youth (Kerns et al., 2016; Van Steensel et al., 2011). Fortunately, researchers have developed evidence-based mental and behavioral health interventions (MH-EBPs) for autistic children to address functional impairment and interference due to co-occurring anxiety disorders (National Autism Center, 2015; Ung et al., 2015; C. Wong et al., 2015). However, researchers inattention to the differences between the settings in which they develop MH-EBPs and the community-based settings in which autistic youth, often from marginalized and/or minoritized communities, may receive care results in a significant research-to-practice gap in the delivery of MH-EBPs to autistic youth (Boyd et al., 2021; Dingfelder & Mandell, 2011; McIntyre & Barton, 2010). Engaging community partners in intervention adaptation may ensure that these MH-EBPs better respond to community-based settings and intervention recipients (Aarons et al., 2011). This study aimed to use and evaluate a community-engaged intervention adaptation method (i.e., Adapted Method for Program Adaptation through Community Engagement [AM-PACE)]; Chen et al., 2013; Yingling et al., 2020) to develop a community-adapted version of Behavioral Interventions for Anxiety in Children with Autism (BIACA; Wood et al., 2009).A complex intervention adaptation mixed methods design was used to obtain community members\u2019 ratings of implementation outcomes and perspectives regarding facilitators, barriers, and possible improvements for the original BIACA intervention, the community-adapted BIACA intervention, and AM-PACE (Creswell & Clark, 2018a). A Community Advisory Board provided ongoing input about study procedures and results while autistic adults, caregivers of autistic individuals, community providers, and community agency leaders participated in and evaluated AM-PACE. These individuals were purposefully sampled for overrepresentation of marginalized and/or minoritized communities. A masked sample of community providers (N = 188) also comparatively evaluated the original BIACA and the community-adapted BIACA. On average, community members gave moderate ratings for implementation outcomes for the original BIACA intervention. Autistic adults and caregivers provided substantially lower ratings than community providers and agency leaders, and these ratings were contextualized in emerging themes from qualitative interviews (e.g., prior therapy experiences). Community suggested adaptations to BIACA were made in domains of content, delivery, and training/evaluation. Initial role-plays of the resulting community-adapted BIACA indicated more favorable ratings of implementation outcomes compared to ratings of the original BIACA. Consistently, masked community providers rated the community-adapted BIACA as more acceptable and appropriate with a higher likelihood of intent to use compared to the original BIACA. This suggests adaptations identified through community engagement may enhance the potential for BIACA to be implemented in community-based settings. In terms of the evaluation of AM-PACE, community members gave high ratings of some implementation outcomes (e.g., acceptability and appropriateness) with more moderate ratings of other implementation outcomes (e.g., feasibility, usability). These ratings were also contextualized in emerging themes from qualitative interviews (e.g., organizational barriers and capacity). Identified adaptations needed to AM-PACE were in areas of content, delivery, and training/evaluation. This evaluation of AM-PACE can be used to support and improve the process for adapting other MH-EBPs for autistic youth in community-based settings or even MH-EBPs for other clinical populations in community settings.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Frequency Syntonization for Decentralized Distributed Phased Arrays
Full text linkThesis (M.S.)--Michigan State University. Electrical and Computer Engineering - Master of Science, 2025This thesis presents the research and development of an alignment method for spatially diverse, decentralized, distributed phased array systems. The challenge of limited access to reliable alignment signals from a destination or other external primary control system is a significant hurdle for distributed antenna systems in the context of emerging 5G/6G technologies. Even without reference signals, the system is designed to remain fully functional. Decentralized and open-looped wireless sensor networks (WSNs) coordination can mitigate these issues. Still, it necessitates a high level of precision in signal agreement for proper signal operation, such as distributed antenna array beam forming.This work presents a wireless distributed system intended to complement a decentralized distributed wireless antenna array for communication and remote sensing systems without needing information from second or third-party entities to achieve consensus. The intent is also to demonstrate the partial independence of the syntonization from the synchronization approach. Through the sole use of software in software-defined radios (SDRs), I explore different parameter estimation techniques designed to reduce the residual error when the system achieves frequency consensus, presented as a proof of concept and initial research into such applications that leverage the use of this technique in legacy architecture.The system uses orthogonal frequency division multiplexing (OFDM) to identify transmitters. It implements an average consensus approach at a system level, which requires minimal prior information from neighboring nodes. This approach ensures that the frequencies converge to the desired residual error tolerance of less than 18\u25e6, ensuring constructive interference with a relative power gain of 90% concerning an ideal constructively interfering set of signals.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Grassroots Climate Justice Innovation Theory
Full text linkThesis (Ph.D.)--Michigan State University. Community Sustainability-Doctor of Philosophy, 2025This dissertation explores the emerging concept of climate justice. I conducted interviews with 12 grassroots climate activists to explore climate justice as an approach to sociopolitical change. All participants are feminist figures of color who were identified by their own communities as leaders in the climate justice movement.Personal stories illuminate important nuance, context, and complexity in the climate justice discourse and highlight the role of underrepresented actors in affecting place-based change. An emergent thematic analysis of these conversations surfaces persistent and damaging impacts of U.S. political and economic systems on marginalized communities and the shared belief that in order to be effective, climate solutions need to acknowledge the interwoven nature of environmental justice, gender equity, and Indigenous resilience. Participants argue for the pressing urgency of both collective action and political resolve to confront the complex challenges of climate change and social inequality. Their experiences on the frontline provide insight into effective actions toward just and sustainable change.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
ADVANCES IN MATRIX AND TENSOR ANALYSIS : FLEXIBLE AND ROBUST SAMPLING MODELS, ALGORITHMS, AND APPLICATIONS
Full text linkThesis (Ph.D.)--Michigan State University. Applied Mathematics - Doctor of Philosophy, 2025This thesis investigates robust and flexible methods for matrix and tensor analysis, which are fundamental in data science. The primary focus of this work is the development of Guaranteed Sampling Flexibility for Low-Tubal-Rank Tensor Completion, a project aimed at addressing the limitations of existing sampling methods for tensor completion, such as Bernoulli and t-CUR sampling, which often lack flexibility across diverse applications.To overcome these challenges, we introduce Tensor Cross-Concentrated Sampling (t-CCS), an extension of the matrix Cross-Concentrated Sampling (CCS) model to tensors, and propose a novel non-convex algorithm, Iterative Tensor CUR Completion (ITCURC), specifically tailored for t-CCS-based tensor completion. Theoretical analysis provides sufficient conditions for low-rank tensor recovery and presents a detailed sampling complexity analysis. These findings are further validated through extensive testing on both real-world and synthetic datasets. In addition to the main project, this thesis includes another one complementary study. The study explores the robustness of CCS model for matrix completion, a recent approach demonstrated to effectively capture cross-concentrated data dependencies. However, its robustness to sparse outliers has remained underexplored. To address this gap, we propose the Robust CCS Completion problem and develop a non-convex iterative algorithm, Robust CUR Completion (RCURC). Empirical results on synthetic and real-world datasets demonstrate that RCURC is both efficient and robust against outliers, making it a powerful tool for recovering incomplete data. Collectively, these projects advance the robustness and flexibility of matrix and tensor methods, enhancing their applicability in complex, real-world data environments.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
RHETORICS OF THE SMALL : THE EVERYDAY PHENOMENA OF THE HOME
Full text linkThesis (Ph.D.)--Michigan State University. Rhetoric and Writing - Doctor of Philosophy, 2025This project investigates the experience of the home as both personal and socio/cultural phenomenon through creative-critical inquiry into the lives and homes of three generations of women in my family. Using a method I developed called \u201csensory interviewing\u201d \u2013 an auto/ethnographical and reflexive form of video interviewing, I focus on capturing the intimate, lived experience of place and how material and everyday encounters shape our individual sense of \u201chome.\u201d By exploring the relationships between bodies, space, and time, I center the three unique stories of my sister, mother, and grandmother to gain insight into their embodied and sensory experiences of the home in how they come to \u2018make\u2019 a home, form a sense of place, and actively construct memory through engagement with the materiality of their daily lives. Building on scholarship in feminist theory, memory studies, phenomenology, multimodality, and cultural rhetorics, I theorize \u201crhetorics of the small\u201d as an embodied practice of attunement to the everyday objects, stories, and practices that create meaning and memory across generations, most especially in sites not traditionally studied as rhetorical (e.g., the domestic/private sphere). The home, while not public, is rhetorical in how it serves as a starting point, as a place from which we go out from, in how we begin to make sense of our lived worlds. I argue that this entanglement of the senses, of memory, and the impressions we leave and are left on us by others serve as a necessary framework for understanding the reverberative e/affects of the small, everyday practices and actions as starting points for change.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
LEVERAGING DIFFERENTIATION OF PERSISTENCE DIAGRAMS FOR PARAMETER SPACE OPTIMIZATION AND DATA ASSIMILATION
No full textThesis (Ph.D.)--Michigan State University. Mechanical Engineering - Doctor of Philosophy, 2025Persistent homology, the flagship tool from Topological Data Analysis (TDA) has been successfully utilized in many different domains despite the absence of a differentiation framework. Only recently a differential calculus has been defined on the space of persistence diagrams thus unlocking new possibilities for combining persistence with powerful solvers and optimizers. This work explores harnessing persistence differentiation for topologically driven data assimilation and for optimally navigating the parameter space of dynamical systems. Specifically, in Chapter 1, I give an overview of this thesis and present background on optimization and persistence optimization. In Chapter 2, I introduce a new topological data assimilation framework, and demonstrate the capabilities of this new method. In Chapter 3, I show how persistence-based cost functions can be constructed and used to optimally traverse the parameter space of a dynamical system. The cost functions are designed by specifying criteria that correspond to the structure of a desirable target persistence diagram while penalizing undesirable persistence features. Other applications of persistent homology are also presented in Chapter 4 where a texture analysis pipeline was developed to quantify specific features of a texture using TDA. Finally, in Chapter 5, I present a time delay framework for modeling metabolic oscillations in Yeast cells and numerical methods are used to locate parameters of the system that lead to limit cycles.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
ESTIMATING AIR INFILTRATION RATES THROUGH LARGE OPENINGS FOR IMPROVED BUILDING ENERGY USE IMPACTS EVALUATION
Full text linkThesis (M.S.)--Michigan State University. Civil Engineering - Master of Science, 2025Industrial buildings represent a substantial portion of building energy consumption throughout the U.S., with heating, ventilation and air conditioning (HVAC) making up approximately 9.3% of net electricity and 6% of natural gas consumption. One of the main drivers of operation and energy use of the HVAC system is infiltration. For industrial buildings, many have a substantial number of large openings for shipping and receiving, often with these doors remaining open for extended period of time. Opportunities to reduce infiltration through these openings exist, such as through the use of air or plastic curtains. However, the relative energy savings impact of the such retrofits is not standardized in part because the baseline level of unconditioned air flowing into the existing large openings is not well established. This study examines wind speed variations impact on air infiltration rates within a large opening in an industrial-style building through experimental testing, in an effort to establish an empirical relationship between weather station wind speed and the wind-driven air flow experienced through large openings. Wind speed measurements were collected from multiple sensors installed at the opening and compared with data from a nearby weather station. Results show that wind speeds at weather station height (~10 m) level (4.75 m/s) were significantly higher than those at the opening (0.72 m/s), with the lowest sensor within the opening recording the highest wind speeds. Results also suggest that compared to the estimated wind speeds based on the existing EnergyPlus Effective Area Infiltration model, air speeds measured at the large opening were 60.9% lower. A data-driven regression model was then developed to estimate wind speed at the opening based on weather-station height wind speed data, achieving an R2 of 0.75, with cross-validation confirming its reliability. The resulting data-driven model can be used to better estimate the air speeds and thus infiltration experienced at large door openings, improving the overall ability of existing models to estimate energy implications of large door openings.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
INTEGRATED MANAGEMENT OF KEY PESTS IN CORN-POTATO SYSTEMS : VOLUNTEER POTATO AND COLORADO POTATO BEETLE
Full text linkThesis (M.S.)--Michigan State University. Crop and Soil Sciences - Master of Science, 2025Colorado potato beetle (Leptinotarsa decemlineata (Say), CPB) and volunteer potatoes (Solanum tuberosum L.) are detrimental pests in potato producing regions. Warming winter temperatures has increased the likelihood of volunteer potato survival, an early season food source for CPB. Therefore, field experiments were conducted in 2023 and 2024 to evaluate integrated management strategies of these key pests. Experiments included: (1) management of volunteer potatoes and CPB in corn rotations using tillage and tank-mixed herbicides-insecticides, and (2) planting delayed potato trap crops to manage second generation CPB. In volunteer potato studies, reduced intensity tillage reduced volunteer emergence by 80% compared to high intensity tillage, due to increased exposure of volunteers to lethal winter temperatures. Late season volunteer control was greatest with mesotrione, which reduced the number and weight of daughter tubers by 55-78% and 80-88%, respectively, in the moldboard plow tillage system. Insecticide tank mixes reduced CPB density on volunteers and decreased defoliation of volunteers throughout the season. Corn injury was less than 5% across all tank-mixed herbicide-insecticide treatments. In the trap crop study, delaying potato trap crop planting by 2 wks resulted in increased CPB density by at least 57% or greater relative to the 0 wk treatment. Trap crop treatments did not reduce the rate of defoliation in the potato crops planted next to the trap crops, resulting in no difference in yield. However, results from this study demonstrate that delaying potato trap crop planting can alter CPB infestation of field edges providing an opportunity for localized management with foliar insecticide applications. Overall, this research investigated multiple integrated management approaches to control these key pests in corn and potato rotations.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Essays on Digital Platforms
Full text linkThesis (Ph.D.)--Michigan State University. Economics - Doctor of Philosophy, 2025This dissertation develops theoretical frameworks to examine how digital platforms shape and monetize interactions among consumers and producers. It analyzes the incentives that drive platforms\u2019 design and pricing decisions, as well as the regulatory implications of these choices. Chapter 1: Price Coherence and Sponsored Search. Online marketplaces lose revenue when consumers discover products through the platforms but purchase directly from sellers at lower prices. To prevent this, platforms often enforce \u201cprice coherence,\u201d requiring sellers to offer their lowest prices through the platforms. Such practices face scrutiny for purportedly raising prices and reducing welfare. I explore the welfare implications of regulating price coherence when a platform may respond by adjusting its online search design. I develop a model in which a platform monetizes seller-consumer access through \u201ctransaction fees\u201d\u2014commission on intermediated transactions\u2014and \u201creferral fees\u201d\u2014proceeds from the sale of prominent search slots. With price coherence, the platform offers many prominent slots to help consumers find high value products but calibrates transaction fees to prevent any price reduction from increased competition. With a ban on price coherence, the platform loses its ability to influence prices through transaction fees and responds by offering fewer prominent slots, stifling competition to bolster its revenue from referral fees. My model thus reveals a novel tradeoff: prices are higher with price coherence, but consumers consider fewer products without it. I show that in face of this tradeoff, regulatory proscription of price coherence may unintentionally lower both total welfare and consumer surplus. Chapter 2: Platform Coherence Policies with a Multiproduct Seller. I study a vertically differentiated product market intermediated by a monopoly platform. A monopoly seller offers a low- and a high-quality product to consumers with heterogenous preferences to purchase through the platform rather than directly from the seller. Absent any restrictions imposed by the platform, the seller may draw consumers to purchase directly through differences in product prices and product availability between its direct and platform selling channels. I characterize the strategic pricing and assortment decisions made by the seller. Strategic assortment can substantially lessen the platform\u2019s ability to monetize the access it provides in buyer-seller interactions. The platform always finds it optimal to implement both cross-channel price and availability coherence policies if feasible. In contrast to general optimality of price coherence in similar markets supplied by a single-product seller, the platform may optimally allow for cross-channel price flexibility if it cannot enforce cross-channel availability coherence. Chapter 3: Product Recommendations with Match Externalities. Platforms designing product recommender systems face a tradeoff between providing familiar \u201csafe\u201d recommendations likely to engage consumers or unfamiliar \u201cdiscovery\u201d recommendations with more engagement uncertainty but higher potential value. Committing to provide discovery recommendations when safe ones offer little value increases buyers\u2019 willingness to pay but may reduce successful consumer-producer matches. I show how match externalities to third-party advertisers can tip the scale of this tradeoff towards safe recommendations to prioritize consumer engagement over value. Although some consumers would prefer discovery, a platform provides them with safe recommendations to increase its revenue from third-party advertisers, compensating the consumers with lower participation fees. Despite reduced recommendation efficiency, consumer surplus increases with the presence of third-party advertisers. These match externalities typically cause a platform to prefer improving the \u201callure\u201d (match likelihood) of discovery recommendations over their \u201csuitability\u201d (expected value from successful matches).Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Investigation of Stochastically Excited Suspension Systems using an Inertially Nonlinear Vibration Absorber with Energy Harvesting Capabilities
Full text linkThesis (Ph.D.)--Michigan State University. Mechanical Engineering - Doctor of Philosophy, 2025The push towards electric vehicles in modern times is complemented by mobile and renewablepower technology. In automotive vehicles, ride comfort and road handling are also important metrics to consider. Energy harvesting shock absorbers (EHSA) have potential, but traditional applications have resulted in tradeoffs between ride comfort, road handling, and power generation. Hence, research involving new technologies for power generation with multi-objective performance capabilities is very valuable. This work specifically investigates a novel approach for vibration suppression and electric power harvesting in systems subjected to stochastic and broadband excitations, focusing on automotive suspensions. The proposed solution harnesses the concept of inertance to provide mass amplification via rotational inertia and also introduces inertial nonlinearity, enhancing bandwidth and overall performance.This work specifically explores vibration suppression, energy transfer, and the qualitativechange in the probability density function (PDF) with the application of a device with nonlinearity due to inertia. This device is an inerter-based pendulum vibration absorber (IPVA). The change in the PDF is called P-bifurcation. The IPVA is first applied to a single-degree- of-freedom (SDOF) spring-mass-damper system subjected to white noise excitation. A perturbation method identifies and tracks bifurcation points, revealing that the marginal PDF of the pendulum\u2019s angular displacement undergoes a P-bifurcation, transitioning from monomodal to bimodal behavior. A cumulant-neglect technique predicts the system\u2019s mean squares, demonstrating significant vibration suppression near the P-bifurcation by transferring kinetic energy from the structure to the pendulum. Results are validated via Monte Carlo simulations (MCS), approximating the PDF and mean squares.The study extends to integrating energy harvesting into the nonlinear device, applying itto a quarter-car model under class C road conditions (average road, ISO 8608). The impact of pendulum length on power generation, ride comfort, and road handling is assessed. Near P-bifurcation, simultaneous enhancements are seen in power output (40%), ride comfort (60%), and road handling (60%) compared to a linear benchmark. A Wiener path integration (WPI) method predicts the PDF and its second derivative, enabling efficient detection of monomodal, bimodal, and rotational PDF regions in the noise intensity-electrical damping plane. MCS confirm performance improvements of up to 43% in energy transfer and 20% in power harvested compared to optimized linear systems, alongside at least 59% gains in ride comfort and road handling. A novel bifurcation detection algorithm reduces computational demands by linking qualitative PDF changes to performance metrics.Experimental studies verify P-bifurcation and the energy harvesting IPVA\u2019s effectivenessin vibration reduction and energy harvesting for a SDOF structure under Gaussian broadband base excitation. Various experimental scenarios help identify unknown mathematical model parameters, minimizing discrepancies between experimental and simulated results for the pendulum\u2019s velocity, with all RMS velocity differences below 3%. The fitted model predicts power, vibration suppression, and P-bifurcation boundaries in the noise intensity-electrical damping plane, corroborated experimentally. Power spectral density analyses reveal bimodal and rotational systems outperform monomodal configurations, enhancing power and suppressing resonant peaks by up to factors of four and two, respectively. Near resonance, mean square relative velocity improves by a factor of two.These findings inform the design and manufacture of a full-scale IPVA-integrated EHSAfor off-road vehicles. The shock design involves balancing durability, weight, ride comfort, energy harvesting, and road handling. The shock absorber undergoes sinusoidal testing on a hydraulic machine to fit a developed mathematical model. A nonlinear least-squares based optimization routine fits model parameters, yielding two viable parameter sets. Numerical simulations implement the shock in a quarter car model with class F road excitation (off-road; ISO 8608) and quantify energy harvesting, ride comfort, and road handling. A correlation between performance and the PDF shape is finally made.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references