USMA Athena
USMA Athena is a secure digital service managed by the United States Military Academy Library to make the work of USMA scholars freely available, while also ensuring these resources are organized to preserve the legacy of USMA scholarship. The mission of USMA Athena is to showcase the academic impact and intellectual capital that has become synonymous with the celebrated heritage of educational prowess attributed to the Long Gray Line. Scholarship submitted to USMA Athena benefits from added visibility and discoverability via Google Scholar in addition to the use of persistent URLs that will provide enduring access to the work over time.
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Recent Submissions
Use of an augmented reality sand table for satellite remote sensing education
(Informa UK Limited, 2022-06-13) O’Banion, Matthew S.; Lewis, Nicholas S.; Boyce, Michael W.; Jordan Laughlin; Majkowicz, Deborah C.
This experiment utilized advanced visualization technology for the delivery of an introductory remote sensing lesson in an undergraduate geography course. Given the numerous immersive visualization solutions available, it is now possible to leverage the capabilities of augmented, mixed, and virtual reality (AR, MR, and VR) technology in a classroom learning environment. For instructors, it is important to understand how advanced visualization technologies can enhance the learning experience and enable greater knowledge retention. To validate the use of an AR sand table/sandbox in a group academic setting, approximately 400 participants were evaluated to assess the impact on students’ retention of both foundational and practical remote sensing concepts. This work represents a between-subjects design with two AR sand table experimental groups (instructor sand table interaction, and student sand table interaction) and one control group with no sand table exposure. The use of the AR sand table in a classroom environment was found to improve retention of foundational remote sensing knowledge and elevate the assessment performance for subjects identified as lower performers.
Interactive Visualization of 3D Coordinate Uncertainties in Terrestrial Laser
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Scanning Point Clouds Using OpenGL Shader Language
(American Society of Civil Engineers (ASCE), 2019-02) O’Banion, Matthew S.; Olsen, Michael J.; Parrish, Christopher E.; Bailey, Michael
Although laser-scanning total propagated uncertainty (TPU) is an active topic in the research community, there is a current dearth of commercial or open-source software for generating point clouds with per-point, three-dimensional (3D) coordinate uncertainties from terrestrial, mobile, and airborne laser scanning. Consequentially, there is a corresponding lack of tools for on-the-fly 3D visualization of these point cloud uncertainties. Visualization tools could be incredibly valuable for analyzing and communicating the spatial variability of uncertainty in a data set, ultimately enhancing both qualitative and quantitative analyses. This study presents an efficient visualization framework for terrestrial laser-scanning (TLS) point cloud uncertainty calculation utilizing the OpenGL Shader Language (GLSL). The methods were tested on four data sets, ranging from a controlled indoor scene containing objects representing simple geometric shapes (e.g., spheres and cones) to a complex forest environment with many types of natural objects. OpenGL shader-based uncertainty visualization was found to aid with the assessment of the effects of modifying models of measurement uncertainty, such as accounting for the nonlinear increase in laser beam radius at short ranges when modeling laser beamwidth-derived uncertainty, as well as range- and angular-based component uncertainties.
Monitoring of a rockfill embankment dam using TLS and sUAS point clouds
(Walter de Gruyter GmbH, 2024-06-14) Bolkas, Dimitrios; O’Banion, Matthew S.; Laughlin, Jordan; Prickett, Jakeb
Terrestrial laser scanning (TLS) and camera-equipped small unmanned aircraft systems (sUAS) are two methods that are often used to produce dense point clouds for several monitoring applications. This paper compares the two methods in their ability to provide accurate monitoring information for rockfill embankment dams. We compare the two methods in terms of their uncertainty, data completeness, and field data acquisition/processing challenges. For both datasets, we derive an error budget that considers registration and measurement uncertainty. We also proceed to merge the TLS and sUAS data and leverage the advantages of each method. Furthermore, we conduct an analysis of the multiscale model-to-model cloud comparison (M3C2) input parameters, namely projection scale, normal scale, and sub-sampling of the reference point cloud, to show their effect on the M3C2 distance estimation. The theoretical methodologies and practical considerations of this paper can assist surveyors, who conduct monitoring of rockfill embankment dams using point clouds, in establishing reliable change/deformation estimations.
Assessment of a Membrane Filter Coated with Hygroscopic Glycerol for Improved Recovery of Airborne Viable Bacteriophage MS2
(Aerosol and Air Quality Research Research, 2024-12-09) Washeem, Mohammad; Vass, William B.; Becker, Drew W.; Shirkhani, Amin; Shankar, Sripriya Nannu; Zhang, Yuetong; Alipanah, Morteza; Fan, Z. Hugh; Lednicky, John A.; Wu, Chang-Yu
The viability of viruses collected on membrane filters during air sampling is compromised by desiccation. This leads to an underestimation of the concentration of viable viruses in the air. We investigated whether adding a hygroscopic glycerol coating to membrane filters could enhance the recovery of viable bacteriophage MS2 collected through air sampling. Mixed cellulose ester (MCE) filters were coated with glycerol and compared with as-packaged filters (APF) as a control to determine the impact of glycerol on MS2 viability. First, MS2 viability upon direct deposition of MS2 suspension on APF vs. glycerol-coated filters (GCF) was assessed at benchtop. On average 121% more viable MS2 were recovered from GCF than APF (p = 0.031). MS2 was then aerosolized and collected onto APF, GCF, phosphate-buffered saline (PBS)-wetted filters (PWF), and gelatin filters (GF). All filter types collected statistically similar (p > 0.05) amounts of aerosolized virus at 50% RH according to RT-qPCR analysis. Viable virus recovery from GCF was significantly lower than from APF (p = 0.011) at 50% RH but significantly higher (p = 0.0004) at 80% RH. APF and GCF preconditioned for 30 minutes at 80% RH were also assessed for MS2 aerosol sampling. Results showed higher viable virus recovery from GCF than either APF (p = 0.021) or GF (p = 0.006). High RH in aerosols facilitated viability conservation of MS2 on GCF, leading to improved recovery of viable virus from membrane filters.
Occupational exposure monitoring of airborne respiratory viruses in outpatient medical clinics
(Taylor & Francis: Aerosol Science and Technology, 2024-10-23) Vass, William B.; Shirkhani, Amin; Washeem, Mohammad; Nannu Shankar, Sripriya; Zhang, Yuetong; Moquin, Tracey L.; Messcher, Rebeccah L.; Jansen, Matthew D.; Clugston, James R.; Walser, Matthew P.; Yang, Yang; Lednicky, John A.; Fan, Z. Hugh; Wu, Chang-Yu
Exposure to airborne respiratory viruses can be a health hazard in occupational settings. In this study, air sampling was conducted from January to March 2023 in two outpatient medical clinics—one primary care clinic and one clinic dedicated to the diagnosis and treatment of respiratory illnesses—for the purpose of assessing airborne respiratory virus presence. Work involved the operation of a BioSpot-VIVAS as a stationary air sampler and deployment of NIOSH BC-251 bioaerosol samplers as either stationary devices or personal air samplers worn by staff members. Results were correlated with deidentified clinical data from patient testing. Samples from seven days were analyzed for SARS-CoV-2, influenza A H1N1 and H3N2 viruses, and influenza B Victoria- and Yamagata-lineage viruses, with an overall 17.5% (17/97) positivity rate. Airborne viruses predominated in particles of aerodynamic diameters from 1–4 μm and were recovered in similar quantities from both clinics. BC-251 samplers (17.4%, 15/86) and VIVAS (18.2%, 2/11) collected detectable viruses at similar rates, but more numerous BC-251 samplers provided greater insight into virus presence across clinical spaces and job categories. 60% of samples from reception areas contained detectable virus, and exposure to significantly more virus (p = 0.0028) occurred at reception desks as compared to the “mobile” job categories of medical providers and nurses. Overall, this study provides valuable insights into the impacts of hazard mitigation controls tailored to reducing respiratory virus exposure and highlights the need for continued diligence toward exposure risk mitigation in outpatient medical clinics.