DRUM - Digital Repository at the University of Maryland

DRUM collects, preserves, and provides public access to the scholarly output of the university. Faculty and researchers can upload research products for rapid dissemination, global visibility and impact, and long-term preservation.

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Submit to DRUM

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Equitable Access Policy

Equitable Access Policy

The University of Maryland Equitable Access Policy provides equitable, open access to the University's research and scholarship. Faculty can learn more about what is covered by the policy and how to deposit on the policy website.
Theses and Dissertations

Theses and Dissertations

DRUM includes all UMD theses and dissertations from 2003 forward.

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Recent Submissions

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    P2E in a Consortium: One Simple Trick to Remove Unwanted Electronic Portfolios!
    (Ex Libris Users of North America (ELUNA), 2025-06-19) Seguin, Linda
    After sharing a single Aleph database for over twenty years, the University System of Maryland & Affiliated Institutions (USMAI) consortium migrated to seventeen Alma Institution Zones (IZs) with a Network Zone (NZ) in 2024. Having once used the "single record approach" to add physical and e-holdings to the same bibliographic record, we found our legacy data was ill-suited for Ex Libris' standard Physical to Electronic (P2E) process of migrating ILS data for e-resources. As designed, if any institution had e-holdings on an Aleph record, then every institution with physical holdings on the same record would get an electronic portfolio for that title in their Alma IZ. Pre-migration cleanup was not feasible, and post-migration cleanup would have been difficult in Alma. The presentation will describe some challenges of P2E and how we discovered that a simple Linux command could prevent these errant portfolios in Alma.
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    Efficiency Gains in Rare Book Assessment: Evaluating Generative AI as an Adjunct Approach
    (2025) Coulbourne, Mark; Jones, Carolina; Grabowsky, Connor
    Months of environmental fluctuations in the rare book storage area compelled the Preservation Department to conduct a condition assessment. To limit the possibility of inattentional blindness and to test the quality of generative AI systems two different generative AI systems were tested against well-trained humans. The test consisted of one-hundred books which were evaluated by humans for damage to the text-block, the spine, the margin/gutter and the paper. The areas were photographed, those photographs and uniform text were input into Gemini Pro and ChatGPT Pro. The human results were compared against Gemini Pro and ChatGPT Pro. Considering generative AI was not designed to perform rare book assessments, the AI systems performed better than expected evaluating the text block, the condition of the paper and suggested preservation actions.
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    Electrolyte design for aqueous Zn batteries
    (Joule, 2025) Heo, Jiyun; Dong, Dejian; Wang, Zeyi; Fu, Chen; Wang, Chunsheng
    Context & scaleZn-based batteries with aqueous electrolytes are garnering great interest as the most promising next-generation batteries due to their intrinsic high safety, low cost, and environmental friendliness. However, the short cycle life of the Zn battery, originating from the low reversibility of the Zn metal electrode, is far from satisfactory. To achieve high reversibility of Zn metal electrode, tackling the water decomposition reaction and the inhomogeneous deposition/dissolution reaction is crucial. We present design principles for aqueous co-solvent electrolytes with high Zn reversibility and suggest a new parameter for accurately selecting beneficial organic molecules for Zn-based batteries. Electrolytes prepared using this principle effectively overcome the challenges in aqueous systems and demonstrate record-high cycling stability. This work provides new insight into aqueous electrolyte systems.Highlights•Thorough electrolyte design principles are suggested for aqueous batteries•An effective descriptor for selecting organic co-solvent is discovered•Designed electrolyte provides high reversibility and cycling stability of Zn batteriesSummaryPolarity scales are often used as descriptors for selecting organic molecules for aqueous Zn battery (AZB) electrolytes. However, failure to accurately predict the solvation of Zn2+ raises questions about their applicability for designing high-performance AZB electrolytes. Here, Dimroth and Richardt's Et(30) polarity scale is introduced as an effective guideline for screening organic molecules. A clear volcanic correlation is demonstrated between Et(30) and Zn Coulombic efficiency (CE). This challenges the common consensus in the aqueous electrolyte design formula, which typically uses highly polar organic molecules to improve Zn CE, and indicates that the roles of organic molecules beyond altering the Zn2+ solvation structure are critical for obtaining high AZB performances. Based on the Et(30) scale, the designed electrolyte achieves a high average Zn CE (99.8%), an exceptionally long cycle life (5,500 h), and a high specific energy (110 Wh kg?1). Et(30) polarity scale offers general frameworks for selecting organic molecules in aqueous electrolytes.Graphical abstract
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    Solvent?Free Electrolyte for High?Temperature Rechargeable Lithium Metal Batteries
    (Advanced Functional Materials, 2023) Phan, An; Jayawardana, Chamithri; Le, Phung, Loan, My; Zhang, Jiaxun; Nan, Bo; Zhang, Weiran; Lucht, L., Brett; Hou, Singyuk; Wang, Chunsheng
    Abstract The formation of lithiophobic inorganic solid electrolyte interphase (SEI) on Li anode and cathode electrolyte interphase (CEI) on the cathode is beneficial for high?voltage Li metal batteries. However, in most liquid electrolytes, the decomposition of organic solvents inevitably forms organic components in the SEI and CEI. In addition, organic solvents often pose substantial safety risks due to their high volatility and flammability. Herein, an organic?solvent?free eutectic electrolyte based on low?melting alkali perfluorinated?sulfonimide salts is reported. The exclusive anion reduction on Li anode surface results in an inorganic, LiF?rich SEI with high capability to suppress Li dendrite, as evidenced by the high Li plating/stripping CE of 99.4% at 0.5 mA cm ?2 and 1.0 mAh cm ?2 , and 200?cycle lifespan of full LiNi 0.8 Co 0.15 Al 0.05 O 2 (2.0 mAh cm ?2 )
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    Optimal bandwidth selection in stochastic regression of Bio-FET measurements
    (Journal of Mathematical Biology, 2025) Melara, Luis; Evans, M., Ryan; Cho, Seulki; Balijepalli, Arvind; Kearsley, J., Anthony
    Biological field effect transistors (Bio-FETs) are modern bioelectronics instruments that offer rapid, low-cost and accurate point of care (POC) biomarker measurements. The time series data produced by these devices contain noise which interferes with quantitative analysis. Stochastic regression, which relies on modeling the measurement with a linear stochastic drift-diffusion equation with unknown coefficients, is employed to separate signal from noise. Coefficients are estimated through local weighted regression and maximum likelihood estimation, both of which depend on a kernel function and the size of a bandwidth parameter. In this work we determine the optimal bandwidth parameter associated with an experimental Bio-FET measurement, by considering three distinct but related kernel functions. Cross validation is performed with respect to different instrument aspect ratios. Results show optimal bandwidth parameters are surprisingly consistent across aspect ratios, and suggest a choice of kernel function.