Scholar Commons - Institutional Repository of the University of South Carolina
Not a member yet
34867 research outputs found
Sort by
Exploring Different Metal-Oxide Cathode Materials for Structural Lithium-Ion Batteries Using Dip-Coating
No full textIn this study, a selection of active materials were coated onto commercially available intermediate modulus carbon fibers to form and analyze the performance of novel composite cathodes for structural power composites. Various slurries containing polyvinylidene fluoride (PVDF), active material powders, 1-methyl-2-pyrrolidone (NMP) and carbon black (CB) were used to coat carbon fiber tows by immersion. Four active materials—lithium cobalt oxide (LCO), lithium iron phosphate (LFP), lithium nickel manganese cobalt oxide (NMC), and lithium nickel cobalt aluminum oxide (NCA)—were individually tested to assess their electrochemical reversibility. The cells were prepared with a polymer separator and liquid electrolytes and assembled in 2025-coin cells. Electrochemical analysis of the cathode materials showed that at C/5 and room temperature the measured capacities ranged from 39.8 Ah kg−1 to 64.7 Ah kg−1 for the LFP and NCA active materials, respectively. The full cells exhibited capacities of 18.1, 23.5, 27.2, and 28.2 Ah kg−1 after 55 cycles for LFP, LCO, NCA, and NMC811, respectively. Finally, visual and elemental analysis were performed via scanning electron microscope (SEM) and energy-dispersive x-ray (EDX) confirming desirable surface coverage and successful transfer of the active materials onto the carbon fiber tows
Archaeological Survey and Testing at Site 38BU1834, United States Marine Corps Recruit Depot, Parris Island, South Carolina
No full textThis report covers the archaeological investigations at site 38BU1834, which falls within the boundary of the Charlesfort/Santa Elena National Historic Landmark on Parris Island, South Carolina. Initial investigations involved a search for activity areas associated with the Spanish pottery kiln discovered in 1993 near the golf course clubhouse. Later work on the site focused on a pond or sinkhole containing a deposit of World War I era U. S. Marine Corps trash and the prehistoric period earth and shell mounds that line the periphery of the pond/sinkhole.https://scholarcommons.sc.edu/archanth_books/1240/thumbnail.jp
Human Contributions to Global Soundscapes Are Less Predictable Than the Acoustic Rhythms of Wildlife
No full textAcross the world, human (anthropophonic) sounds add to sounds of biological (biophonic) and geophysical (geophonic) origin, with human contributions including both speech and technophony (sounds of technological devices). To characterize society’s contribution to the global soundscapes, we used passive acoustic recorders at 139 sites across 6 continents, sampling both urban green spaces and nearby pristine sites continuously for 3 years in a paired design. Recordings were characterized by bird species richness and by 14 complementary acoustic indices. By relating each index to seasonal, diurnal, climatic and anthropogenic factors, we show here that latitude, time of day and day of year each predict a substantial proportion of variation in key metrics of biophony—whereas anthropophony (speech and traffic) show less predictable patterns. Compared to pristine sites, the soundscape of urban green spaces is more dominated by technophony and less diverse in terms of acoustic energy across frequencies and time steps, with less instances of quiet. We conclude that the global soundscape is formed from a highly predictable rhythm in biophony, with added noise from geophony and anthropophony. At urban sites, animals experience an increasingly noisy background of sound, which poses challenges to efficient communication
‘And on one toils, into the hill’: Working and walking in Nan Shepherd’s North East
No full textThis article considers the duality of working and walking in Nan Shepherd’s writings about the North East of Scotland. Exploring Shepherd’s works from the perspectives of social and intellectual history, it considers the ways in which she represented both working and walking as labour during the first half of Scotland’s twentieth century
Trios for Oboe, Bassoon, and Piano by Underrepresented Composers: An Annotated Bibliography and Performance Guide
No full textThe purpose of this project is to highlight repertoire for the trio of oboe, bassoon, and piano, focusing on works by historically underrepresented composers, specifically women and people of color (including Black, Latinx, Indian, Asian, and Native American composers), as well as my performance suggestions and comments for each piece. By creating an annotated bibliography and providing performance insights for each piece, the author seeks to increase the visibility and accessibility of these compositions. This research reflects a broader effort to diversify classical music, promoting works that mirror our society’s diverse cultural landscape. As a first of its kind, this document addresses the lack of resources on trios for these instruments by underrepresented composers and draws upon composer interviews, score analyses, and conference materials. Although limited to pieces available at the time of publication, the research will continue online through The Diverse Bassoon website, providing a growing archive of compositions that encourage performers to explore new repertoire and expand their musical range
A Multifaceted Perspective of Scaling Entrepreneurial Innovation and Impact in Developing Country Contexts
No full textThis paper redefines the understanding of venture scaling in emerging and developing countries through a longitudinal case study of over a decade of transformative growth by Gojek, a local venture in Indonesia. Contrary to the replication logic common among global players—which prioritizes rapid and broader market opportunity expansion using a single, proven business model—Gojek adopted a more incremental and depth-oriented approach. By identifying untapped local demands and developing new market opportunities through stacking different business models, Gojek generated both demand- and supply-side complementarities within its business model portfolio that led to subsequent scaling. The findings suggest that scaling in developing countries requires a multifaceted perspective, and that exploring local market opportunity deeply enables ventures to discover new opportunities and capitalize on them by operating multiple business models within the portfolio
Exploiting Structures in Reinforcement Learning: Multi-Agent Homogeneity, Euclidean Symmetry, and Natural Languages
No full textReinforcement learning (RL) has emerged as a powerful paradigm for decision-making in complex environments. However, many RL tasks exhibit inherent structural properties—such as homogeneity, symmetry, and linguistic patterns—that are often underutilized, leading to inefficiencies in learning and generalization. This dissertation systematically exploits these structures to improve the efficiency, scalability, and robustness of RL algorithms across multi-agent and sequential decision-making settings. First, we investigate homogeneity in multi-agent systems, where agents share similar roles and objectives. By leveraging this structure, we develop communication-efficient actor-critic methods for homogeneous Markov games, enabling scalable learning with reduced coordination overhead. Second, we introduce Euclidean symmetry in RL, demonstrating how equivariant function approximators can significantly enhance sample efficiency and generalization in spatially structured tasks, such as robotic control. Third, we integrate large language models (LLMs) into RL to improve sequential decision-making while avoiding expensive retraining. Our framework efficiently combines LLM inference with RL-based optimization, leading to better adaptability and reduced computational costs in contextual decision-making tasks. Finally, we explore Markov Potential Games (MPGs), a subclass of multi-agent RL with inherent homogeneity. We develop best-response learning dynamics that mitigate non-stationarity and improve equilibrium quality, providing theoretical guarantees on convergence and the first known Price of Anarchy (POA) bounds for policy gradient methods in MPGs. Through extensive theoretical analysis and empirical validation on diverse benchmarks, this work demonstrates the power of structural exploitation in RL. By leveraging homogeneity, symmetry, and natural languages, this research lays the foundation for more efficient, generalizable, and scalable RL algorithms, with applications in multi-robot coordination, traffic management, recommendation systems, and strategic game playing
Stories Between the Stacks: Current Black Women School Librarians\u27 Lived Experiences
No full textBlack women school librarians navigate complex professional landscapes shaped by their lived experiences, intersecting identities, and systemic barriers. Despite their significant contributions to school librarianship, their perspectives remain largely absent from scholarly work. This qualitative study explored how the lived experiences and positionalities of Black women school librarians shape their practices. It addressed the critical gap in research on Black women school librarians. Grounded in Black Critical Theory (BlackCrit) and guided by Black feminist-womanist storytelling, this study employs a narrative approach to explore the experiences of four Black women school librarians in the Southeastern Region of the United States. Data collection methods included in-depth semi-structured interviews and a focus group interview. Through the stories, the study illuminates the persistent anti-Blackness these librarians encountered in K12 school environments, including racial microaggressions and institutional constraints on culturally responsive practices. Regardless of these barriers, participants engage in deliberate acts of resistance and care, including culturally affirming collection development, embedding diverse literacy practices into their programming, and adopting othermothering practices to foster student success and well-being. It examines the barriers and challenges four Black women school librarians face and the strategies they employ to overcome them. The findings reveal that Black women school librarians are knowledge curators, mentors, and advocates, disrupting dominant narratives that often exclude Black voices. However, their work continues to be undervalued within the broader education and library science profession. By centering on Black women school librarians’ lived experiences, this research calls attention to the need for changes in school librarianship, including prioritizing culturally sustaining pedagogies and fostering transformative love in school libraries. This study contributes to scholarship on Black women’s knowledge production in education and librarianship. It demonstrates how Black women school librarians actively shape the field despite systemic challenges. It underscores the necessity for school librarianship to move beyond white hegemonic norms and adopt culturally responsive frameworks that acknowledge and affirm Blackness. By amplifying the voices of Black women school librarians, this research advocates for a more equitable and just profession
Experiences of Adolescent and Young Mothers Through Pregnancy and Motherhood and the Influence of Stressors and Supports
No full textAim: To describe how stressors and supports influence young mothers’ emotional wellbeing during pregnancy and postpartum. Design: Semi-structured interviews analyzed using grounded theory based on Corbin and Strauss. Methods: Twenty young mothers between 17-25 years old with children under 3 years old were interviewed about their emotional wellbeing, social supports, and stressors during pregnancy and postpartum. Interviews were recorded and transcribed verbatim. Using theoretical sampling, open coding was completed in NVivo and secondary coding was completed in Microsoft Excel. Results: Eleven themes were derived from the qualitative analysis and can be organized into four main categories: (1) experiences and perceptions of pregnancy and motherhood, (2) stressors experienced during pregnancy and motherhood, (3) social supports experienced during pregnancy and motherhood, and (4) the transition from pregnancy to motherhood. Conclusions: Young mothers began pregnancy with overwhelmingly negative feelings about the prospect of motherhood. Emotional support from peers, romantic partners, and family members helped some mothers develop more positive feelings towards motherhood. Implications: Future interventions may want to strengthen the mother-daughter relationship as young mothers relied on their mothers to provide the emotional support and friendship that they would have otherwise sought from friends
An Exploratory Study of Disclosure of X-Linked Conditions Between Mothers and Daughters
No full textCarriers of X-linked conditions, both asymptomatic and symptomatic, face unique challenges regarding their experiences navigating the healthcare system and understanding implications of their carrier status. Studies show that mothers are known to be the main communicators of genetic information within their families, but in families affected with X-linked conditions, communication between mothers and daughters are hindered by factors such as lack of knowledge about the condition and reproductive implications, lack of emotional support, anxiety, and uncertainty about how to initiate these conversations. The purpose of this study was to explore the motivations behind mothers\u27 decisions to initiate conversations with their daughters, identify current facilitators and barriers to these discussions, and provide suggestions for future resource development. We surveyed mothers with daughters at risk or known to be carriers of X-linked conditions and conducted virtual semi-structured interviews with selected mother-daughter pairs. Participants were recruited online through social media groups, email groups, and X-linked condition advocacy groups. Ninety-two survey responses were included in the data analysis, and seven interviews were conducted. Thirteen X-linked conditions were represented in the data. Participants identified the most difficult topics to discuss with their daughters were life expectancy, reproductive risks, symptomatic carrier risks, and reproductive options. About 60% of participants felt comfortable and prepared for these conversations. Many expressed a need for additional resources, including accessible information about medical and reproductive implications of being a carrier, support groups for both mothers and young carriers, mental health resources, information about reproductive options, and practical guides informed by lived experiences. The helpfulness of genetic counselors and healthcare providers in supporting these conversations was found to be variable among participants. The study highlights gaps in current support systems and offers recommendations for future resource development to better serve the needs of mothers and daughters in the X-linked condition community. Understanding the needs of this community can also help inform education and resources aimed to better equip healthcare providers with the ability to support carriers as they navigate conversations with their relatives about the condition in their family