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Unsettling Femininity in Ottessa Moshfegh’s My Year of Rest and Relaxation
No full textThis thesis covers how Ottessa Moshfegh’s My Year of Rest and Relaxation critiques traditional understandings of femininity and the inadequacy of neoliberal feminism to address the systemic issues that women face. Using Lauren Berlant’s concept of femininity as a genre, this thesis traces how Moshfegh implements disgust and abjection to reject mandates of cleanliness and emotional labor that are central to traditional femininity. Moshfegh also utilizes disgust and the narrator’s attempt at a year-long sleep to resist the ideals of productivity and self-care that are central to neoliberal feminism. In employing these affects, Moshfegh resists the social structures that exploit women’s labor with the false promise of empowerment. However, the novel refuses to give an alternative or offer a resolution for these failures and instead portrays the narrator’s resistance as futile. The lack of resolution resists traditional narrative arcs of transformation, creating an unsettling reading experience. The unresolved nature of the novel then functions as a critique of the inescapability of restrictive frameworks when met with individual resistance, thus calling for a broader consideration of collective resistance towards oppressive systems
Laboratory Performance Evaluation of Hot Mix Asphalt Mixtures With Incorporations of Different Recycled Plastic Additives Using the Dry Method
Full text linkAsphalt pavements are susceptible to distresses such as cracking, rutting, and moisture damage, which reduce service life and increase maintenance costs. This study evaluated the use of recycled materials from HDPE and LDPE plastics (shredded and pelletized) and PET fibers of two lengths as asphalt mixture additives to provide a sustainable approach to improve performance. The materials were incorporated into two control mixtures designed with the Balanced Mix Design (BMD) method. Laboratory testing assessed cracking and rutting resistance, moisture susceptibility, abrasion resistance, and dynamic modulus across a range of conditions.
Results showed that PET fibers improved cracking resistance due to a reinforcement effect during crack formation. In contrast, plastics, particularly LDPE, significantly increased stiffness and rutting resistance but reduced cracking resistance. The addition of either plastics or fiber also improved abrasion and moisture resistance. Dynamic modulus tests confirmed that plastics increased the stiffness of the mixture, while fibers provided a more flexible response.
Combinations of the additives exhibited that the stiffening due to plastics affected the mixture performance, limiting the benefits of fibers and reducing the feasibility of using HDPE and LDPE to improve the overall asphalt concrete behavior. In addition, fiber-reinforced mixtures at lower binder contents still met performance thresholds, showing potential for cost savings. Overall, recycled plastics enhance rutting resistance, while PET fibers offer a promising solution to improve cracking resistance in asphalt mixtures
A Parametric Study of Compact Wind Borne Debris in Tornadoes
Full text linkDebris lofted and transported by tornadoes is a significant source of damage during these storms. Several approaches have been taken to model such debris flight, ranging in complexity from fine-scale CFD simulations to coupling the compact debris flight equations with simplified analytic models for the tornado vortex. Both approaches have their merits, though the latter comes with significantly lower computational costs. Despite the simplifications, this second approach has successfully captured details of debris flight events established in post-tornado forensic surveys. Herein, we take advantage of the low computational cost of the latter approach to undertake a detailed parametric study of compact debris flight in tornadoes. The tornado was simulated using the Baker and Sterling vortex model and the compact debris flight equations. The tornado model is parameterized in terms of a tornado aspect ratio (δ = zm/rm), the swirl ratio, (S = vm/um), and the tornado Froude number (Ψ = grm/u2m). For the standard compact debris flight model, the debris is characterized by Φ = ρair ArmCD /2m.
However, unlike more straight-line windstorms, such as gust fronts of hurricanes, tornadoes have relatively small radii. Therefore, near the center of the tornado, there can be a significant radial pressure gradient. This pressure gradient has the potential to produce an additional force on a piece of debris due to the pressure differential across the surface of the debris. This ‘buoyancy’ force can become significant for less dense debris such as wood. To illustrate this, a simulation was run using the approximate wind field for the July 1, 2023, Didsbury, AB EF4 tornado. The simulation was run for a 20 cm wooden sphere with and without the additional buoyancy force. Their result shows significant differences in the trajectories in the modeled radial location during flight. Including the buoyancy force introduces a second debris parameter Γ = ρair /ρdebris. There are, therefore, three tornado parameters (δ, S, Ψ), two debris parameters (ϕ, Γ) and the initial conditions which require specification of the vertical and radial initial locations and the three components of the initial debris ii velocity for a total of five parameters and five initial conditions.
A large-scale parametric study was done by changing these parameters and initial conditions. Then, a series of simulations are run for a tornado ranging from EF2 to EF5 scale. Debris simulated ranges from tiny raindrops and sediment through larger aggregates like gravels and wood chunks to cars. The result highlights the conditions under which debris can remain airborne for prolonged periods, when debris will be lofted and ejected radially, and when debris will simply fall out of the wind field. It is seen that the visible core of the tornado can be considerably smaller than the actual region of extreme wind speeds, as the visible core only shows small-scale debris that is drawn in and lofted by the tornado. Whereas large-scale debris can remain in the air well outside the visible core
Mechanistic Insights Into Polymer-Assisted Graphene Exfoliation: The Roles of Velocity, Adhesion, Cohesion, Temperature, Peeling Mode, and Edge Defect via Coarse-Grained Molecular Dynamics
No full textGraphene exfoliation is a critical step in the fabrication of high-quality graphene
layers. However, the underlying fracture mechanisms remain poorly understood. In this
work, I employed coarse-grained (CG) molecular dynamics (MD) simulations to
investigate how factors such as interfacial binding energy, substrate cohesion, temperature,
peeling mode, and edge defects influence the outcome of the exfoliation process. To model
polymer-assisted mechanical exfoliation, I used a finite-size system in which multilayer
graphene (MLG) is sandwiched between two thin polymer films. Leveraging the
spatiotemporal efficiency of the CG model, I performed fifty simulation iterations per
parameter set and analyzed the results from a probabilistic perspective.
The simulation results reveal that interfacial adhesion plays a pivotal role in
determining exfoliation failure modes—governing whether the failure occurs through
adhesive separation at the polymer–graphene interface or through successful exfoliation of
graphene layers. At low interfacial binding energies, adhesive failure is predominant. As
the interfacial binding energy increases, the failure mode shifts toward layer separation
within MLG. A sharp transition zone exists between these regimes, where the probability
of exfoliating different numbers of graphene layers becomes highly sensitive to interfacial
adhesion strength.
Additionally, I found that temperature, substrate adhesion, and peeling mode can
modulate this transition. Notably, corner peeling introduces greater localized stress
compared to side peeling, enabling monolayer exfoliation under conditions where
interfacial and cohesive energies are comparable.
To further investigate the role of edge defects, I modified the CGMD model by
introducing edge cracks in MLG, which was treated as a stand-alone system. By
systematically varying the crack length and model dimensions, I found that longer edge
cracks significantly reduce the exfoliation force required for layer separation, while shorter
cracks demand higher forces to initiate fracture. These results suggest that edge crack
defects can be deliberately engineered to improve exfoliation efficiency and enable higher
control over the location and propagation of fractures.
Overall, this thesis provides new insights into the underlying mechanics of
graphene exfoliation, establishing a computational modeling-based probabilistic
framework for predicting failure modes. The findings demonstrate how interfacial
adhesion, peeling configuration, and defect engineering can be strategically manipulated
to optimize exfoliation outcomes and facilitate the reliable production of high-quality
graphene for a wide range of advanced applications
Emerging Applications on Reconfigurable Computing Platforms
Full text linkSecurity and high-performance computing have become two of the most critical demands in modern technology. The increasing complexity of digital systems, the need for real-time processing, and the emergence of sophisticated cyber threats require computing solutions that balance computational power with adaptability and security. Reconfigurable computing platforms, particularly Field-Programmable Gate Arrays (FPGAs), offer a promising solution to these challenges by combining flexibility with hardware acceleration. Many new applications have emerged with the developing of reconfigurable platforms.
FPGAs can be utilized in two primary directions: as control and high-precision measurement units for security-sensitive applications, and as accelerators capable of outperforming GPUs in specific computational workloads. This dissertation explores both of these directions by developing FPGA-based solutions for time-domain reflectometry (TDR), finite-difference time-domain (FDTD) simulations, SPICE-based power electronics simulation, and recurrent neural network (RNN) training. The TDR implementation provides a high-precision diagnostic tool that has been further adapted to enhance hardware security by detecting unauthorized probes in communication lines. The FPGA-based FDTD accelerator enables efficient simulations for designing ultra-compact photonic devices, demonstrating the advantages of hardware acceleration in scientific computing. Additionally, a SPICE accelerator has been developed to optimize the design process of LLC converters in power electronics, reducing simulation time while maintaining accuracy. Finally, an FPGA-based RNN training accelerator is introduced to address the challenge of real-time learning, showcasing how FPGAs can be leveraged for emerging AI applications
Teacher Support and Professional Development Needs in a New Virtual Academy
Full text linkABSTRACT
As the need for virtual learning options for K-12 public students rapidly grew in large part as a response to COVID-19, Foothills Virtual Academy[1] (FVA) has developed as an option for online learning for students enrolled in the School District of Foothills County[2] (SDFC), a district of approximately 16,000 students located in South Carolina. This educational program offers families the option for their students to become full-time virtual students while still remaining enrolled as a student in SDFC. This program features instructional programs specifically tailored for each age and grade level and features a mixture of synchronous and asynchronous learning opportunities through a variety of online platforms. With students from Kindergarten through 8th grade in the district choosing this option, it requires a separate allocation of teachers and support personnel to staff and operate. Properly supporting and preparing these teachers and staff is important so that they can provide the best learning opportunity for all of the students in SDFC regardless of their learning method, race, socioeconomic level, or location. New online programs like FVA are an important piece of a school system’s instructional delivery model. While teachers need support to be able to teach effectively in virtual settings, the types of supports and professional development teachers need is not well understood. This study helped to determine the types of support and professional development the teachers and staff of this new program needed in order to feel supported and be successful in educating each and every student enrolled in SDFC. As the district moved forward, it was important that the teachers in this program felt supported and prepared so that appropriate time, resources, and effort could be dedicated into helping the teachers be better prepared to teach in this new format and program. Results may help inform other districts in South Carolina and around the nation as they face similar issues and seek options for online learning.
[1] Foothills Virtual Academy (FVA) (see Footnote 1) is a pseudonym to protect the identity of the school district program.
[2] School District of Foothills County (SDFC) (see Footnote 2) is a pseudonym to protect the identity of the school district
The New Road Chosen: An Examination of Why Black Educators Are Choosing Alternative Certification Pathways
Full text linkThis narrative study explores the experiences of eight Black educators who entered the teaching profession through alternative certification programs. Alternative certification programs were originally designed to address teacher shortages by providing individuals with a college degree a fast-track route to teacher licensure; however, research reveals an extreme shortage of Black educators and a growing number of Black educators completing alternative certification pathways. Grounded in Black Critical Theory (BlackCrit) and Social Cognitive Career Theory (SCCT), this study examines how anti-Blackness impacts the Black educator pipeline and how self-efficacy beliefs, perceived outcomes, personal goals, and contextual variables influence career decisions. Findings reveal that both personal influences and alternative certification program features significantly shaped participants\u27 pathways into teaching. The broad theme of influence emerged across all narratives and was broken down into subthemes such as divine influence, relational influence, purpose-driven influence, and the impact of life and societal events. Additionally, program features—both beneficial and challenging—were present in every participant’s account. This study provides a deeper insight into the factors that attract Black professionals to the field through alternative pathways, contributing to strengthening the current research on the Black educator pipeline and offering implications for both traditional teacher preparation programs and alternative certification routes seeking to better support Black educators
Upstate South Carolina Mental Health and Sport Initiative: Contributing Solutions to the Mental Health Crisis Via Improvement of Mental Health Literacy Among Adults in Youth Sport Communities
Full text linkThis study contributed solutions to the youth mental health crisis by providing effective options for mental health awareness training (MHAT) that can be utilized in youth sport for increasing mental health literacy (MHL) among adults. Widely implementing MHAT has the potential to improve youth mental health status through increased help-seeking behaviors by adults. This study first evaluated whether mental health status and MHL are correlated in a youth sport setting with significant results indicating that investing time and resources into MHAT is worthwhile. Next, two MHAT modules were evaluated to determine their effectiveness for increasing MHL among this audience, i.e., one well-established (Mental Health First Aid - MHFA) and one new (ACT! Mental Health Awareness Certification) program.
Results indicated that both MHAT courses effectively increased MHL and its factor of knowledge about mental health, meaning they each could be considered by sport organizers for implementation among adults within their organizations. There were not significant differences found between the effectiveness of MHFA and ACT!, indicating that the newly developed 2-hour ACT! Certification performed just as well as the well-established 8-hour MHFA course and provides a promising new option that may be more viable for wide implementation. Neither MHAT module significantly changed outcomes of attitudes toward mental health.
The results from this study indicate that MHAT may be a great addition to training offered through youth sport organizations for improving MHL. Further, it has validated a new MHAT course, the ACT! Certification, that should be considered for wide implementation by sport practitioners
Synthesis of Nanoparticles in Silicate Matrix and Stimuli Responsive Nanocomposite Polymer Films
Full text linkInteractions between aqueous metal ions and soluble silicates lead to the formation of insoluble metal silicate complexes that form nanoparticles via condensation polymerization. Metal silicates function as nanoreactors, effectively condensing metal ions into nano-sized particles that can undergo further chemical transformations. Core-shell nanostructures present an intriguing strategy for integrating materials with different properties. The silicate shell around the silver nanoparticles can be successfully infused with other metal ions, enabling subsequent reactions to tailor their properties. Silver nanoparticles exhibit strong interactions with light, surpassing other chromophores, including noble metal nanoparticles, due to their highly efficient surface plasmonic resonance. The unique optical properties of silver nanoparticles can be integrated with new functionalities by incorporating different materials into a single nanostructure, forming hybrid silver nanoparticles. The silicate shell around the silver nanoparticles can be utilized as a scaffold for complexing other metal ions, opening a possibility for the synthesis of different shells. Chapter 1 is more focused on metal silicate complex formation studies, and Chapter 2 explains the attempt to incorporate new materials via infusing metal ions into the silicate matrix, followed by further chemical reactions. Synthesizing a metal sulfide shell around the silver core to integrate semiconductor properties and plasmonic properties is challenging because the silicate layer is permeable to sulfide, and the Ag has a higher affinity to sulfide compared to most metals. The silver core is incorporated with CuS and ZnS using the proposed model, but the long-term stability of the hybrid nanoparticles needs to be addressed. Lanthanide ions are another important metal silicate iv forming group. Eu3+ has successfully been used to incorporate photoluminescence properties into AgNPs using the proposed model integrating both plasmonic and photoluminescence properties.
Chapter 3 discusses polymer-based stimuli-responsive self-folding materials. Polymers can be doped with various species, such as metal ions, molecules, or nanoparticles, to develop stimuli-responsive, self-folding materials. Self-folding behavior can be achieved by generating differential responses to external stimuli due to the inhomogeneous properties within the polymer films. To address the delamination issues in bilayer polymer films, plasma and ozone oxidation treatments, as well as mechanical compression, were explored to enhance interlayer adhesion. Additionally, a novel approach was developed using homopolymer films, where only one side is selectively doped with various species. This method enables the fabrication of stable, stimuli-responsive, self-folding polymer films with improved structural integrity and performance
Domain Decomposition for Coupled Systems of Fluid-Structure Interaction and Numerical Modeling for Thin Film Polymers
Full text linkWe consider two primary areas of physical application in this work: fluid interaction systems with either linear elastic structures or with poroelastic structures, and thin film polymers, where the majority of the work focuses on the fluid-structure interaction systems.
In the first chapter, we present a strongly coupled partitioned method for fluid structure interaction (FSI) problems based on a monolithic formulation of the system which employs a Lagrange multiplier (LM). We prove that both the semi-discrete and fully discrete formulations are well-posed. To derive the partitioned scheme, a Schur complement equation, which implicitly expresses the Lagrange multiplier and the fluid pressure in terms of the fluid velocity and structural displacement, is constructed based on the monolithic FSI system. Solving the Schur complement system at each time step allows for the decoupling of the fluid and structure subproblems, making the method non-iterative between subdomains. We investigate bounds for the condition number of the Schur complement matrix and present initial numerical results to demonstrate the performance of our approach, which attains the expected convergence rates.
Next, we consider the employment of a projection-based reduced order model (ROM) on one or both subdomains. The inclusion of ROMs in the non-iterative partitioned scheme provides a more robust framework and offers a cheaper alternative to the full order model in terms of computational time and the size of the linear systems. Utilizing the supremizer enrichment technique, we offer detailed investigations into the performance of our method with respect to the use of supremizers and with respect to the basis sizes of the reduced order variables. Results indicate that the ROM-ROM coupled formulation yields results that agree well with the full order solution in a shorter computational time and with a large reduction in the size of the algebraic systems.
We then move from considering a linear elastic structure to a poroelastic one, in which a fluid flow modeled by Darcy\u27s law saturates an elastic structural skeleton. Similarly to the linear elastic case, we develop a monolithic formulation of the system that uses three LMs to enforce boundary conditions. We show well-posedness, stability, and convergence results for this formulation and then develop a non-iterative partitioned method based on the monolithic system for its solution. We propose a preconditioner for the Schur complement system at the center of this partitioned scheme and demonstrate the numerical performance of the method over a range of parameters. Implementing ROMs in this context, we conduct reproductive and predictive studies with respect to the physical parameters. As in the linear elastic case, our method proves to be robust, and the computational gains provided by the inclusion of the ROMs improves the viability of the scheme.
Lastly, the self-healing process of thin film polymers is modeled numerically under two different temperature regimes. We then consider optimization problems which provide insight into the behavior and structure of these self-healing polymers