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.

Submit to DRUM

Submit to DRUM

To submit an item to DRUM, login using your UMD credentials. Then select the "Submit Item to DRUM" link in the navigation bar. View DRUM policies and submission guidelines.
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.

List of Communities

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UM Community-managed Collections

Recent Submissions

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    Satellite Orbit Simulation to Support Sensor Calibration/Validation
    (2026-08-19) Liu, David; Bai, Yan; Shao, Xi; Cao, Changyong; Bai, Yan; Shao, Xi; Cao, Changyong
    This presentation was shared at the in-person conference of the 2026 ESSIC/CISESS Summer Internship Program held on 19 August 2026. The slides were presented by David Liu, a student at Marriotts Ridge High School, under the mentorship of Yan Bai (UMD/ESSIC/CISESS), Dr. Xi Shao (UMD/ESSIC/CISESS), and Dr. Changyong Cao (NOAA). In this presentation, the intern examined satellite orbit prediction using Two-Line Element (TLE) data and the Simplified General Perturbations 4 (SGP4) propagation model, with attention to orbital perturbations and their effects on prediction accuracy. The study also compared Systems Tool Kit (STK), a high-fidelity aerospace analysis platform, with Zerua, a web-based orbital visualization tool, and applied Zerua to simulate satellites from the Joint Polar Satellite System (JPSS) and the six-satellite COSMIC-2 constellation. The simulations were used to visualize satellite orbits and support analysis of satellite positioning, overpasses, and coordinated observations relevant to sensor calibration and validation. This internship study provides an important foundation for future satellite orbit prediction and coordinated observation studies, contributing to advancements in environmental monitoring and the evaluation of Earth-observing satellite sensor data quality.
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    Satellite Orbit Simulation to Support Sensor Calibration/Validation
    (2026) Liu, David; Bai, Yan; Shao, Xi; Cao, Changyong; Bai, Yan; Shao, Xi; Cao, Changyong
    Satellite orbit predictions are utilized to determine a spacecraft’s timing and position relative to Earth, which are necessary for identifying overpasses, coordinating observations, and supporting the calibration and validation of environmental satellites. This study examines how satellite trajectories can be predicted using Two-Line Element (TLE) data and the Simplified General Perturbations 4 (SGP4) model. It considers factors that alter satellite orbits, including Earth’s nonspherical gravity, atmospheric drag, solar radiation pressure, Earth and ocean tides, the gravitational pull of the Sun and Moon, and spacecraft maneuvers, all of which can reduce prediction accuracy over time. To do so, the study compares Systems Tool Kit (STK), a high-fidelity aerospace analysis platform, with Zerua, a more accessible web-based 3D satellite visualization tool. Zerua was used to simulate satellites from the Joint Polar Satellite System (JPSS) and the six-satellite COSMIC-2 constellation and to examine their orbits, ground tracks, and opportunities for coordinated observations. Reliable orbit prediction helps ensure that their measurements can be accurately calibrated. Overall, this study shows how satellite orbit simulation and visualization can support more reliable Earth-observing data and strengthen the environmental information scientists use to better understand changes in Earth’s systems. These applications are relevant to environmental science because these satellites collect data used for weather forecasting, climate research, and environmental monitoring.
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    Maryland Voters’ Attitudes About Their Typical Voting Experience
    (2026-09) Hanmer, Michael; Gibson, Isabelle
    In Maryland, there are essentially three ways of casting a ballot: 1) in-person on Election Day at a neighborhood precinct; 2) in-person early, before Election Day, at a countywide early voting center; or 3) using a mail ballot that a voter returns by mail or drops off. In the 2024 elections, voters were split almost evenly across these three modes of voting. As the 2026 primary and general elections approached, we sought to learn about the proportion of Marylanders who have used each of these modes of voting, their overall satisfaction with their typical voting experience across the modes they have used, and about key aspects of the voting experience. This report presents the results of a survey of 1,001 Maryland adult citizens, conducted from April 15-26, 2026. The questions discussed here focused on their typical voting experience. Our results can be summarized straightforwardly. Overall, Maryland voters express high levels of satisfaction with each mode of voting: 65.8% report being very satisfied with their typical precinct voting experience on Election Day, 62.8% with voting early in-person, and 63.4% with voting by mail. The proportion indicating that they are somewhat satisfied was also high across modes of voting, with 29% of those who have voted on Election Day, 31.3% of those who have voted early in-person, and 31% of those who have voted by mail providing this response. As discussed below, satisfaction with key components of the voting experience, such as the performance of poll workers (election judges), is also high.
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    "Think, Check... and Think Again:" A Checklist
    (2026) Wilson, Michelle
    This checklist, produced to accompany a poster presentation at the 2026 Charleston Conference, is a distillation of preliminary findings from an in-process research study that seeks to evaluate a growing class of English-language journal titles owned by Chinese institutions. Standard journal evaluation tools do not tell researchers who owns, funds or supervises a journal. This ongoing project combines a literature review with a structured content analysis of 350 journals and aims to produce a practical tools for librarians can use with researchers acting as authors, peer reviewers, and especially for prospective editors or board members, where a named, ongoing affiliation may need to be disclosed to employers and funders. However, Chinese-owned journals are the test case – not the limit: the same questions about ownership, sponsorship and funding apply to any journal, and the aim is informed navigation, not avoidance and the overall goal of this project is to make ownership and sponsorship a routine part of journal evaluation, alongside indexing, impact and editorial practice.
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    America at 250: Library Programming on Black Americans in the Founding Era, A Survey
    (2026-10-09) Baker, Lindsey; Harper, Arthur; McPherson, Shabrina; Sweeting, Lana; Wilson, Aaron; Robinson, Deborah
    In 2025, a team of ALA Emerging Leaders and mentors from BCALA designed a toolkit for libraries, schools, and museums incorporating Black history and agency into their 250th U.S. Anniversary celebrations. The America at 250: Black Perspectives of the Founding Era toolkit provided information professionals with a timeline of the founding era, five major themes, discussion questions, and potential programming around the themes. Institutions across the United States utilized this toolkit to design programs specific to their patrons’ interests and local history. This session will review some of the successes and challenges libraries experienced in using the toolkit, lessons learned from creating a national toolkit, and ways libraries can continue to use the toolkit beyond 2026.