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    The Impact of Periodic Low-Stakes Testing on Environmental Engineering Education
    (ASEE, 2019) Murray, Kyle R.; Sheehan, Nathaniel
    Perhaps the most fundamental goal in education is achieving student retention of new information in order to accomplish learning outcomes. Scores of educational studies coupled with a plethora of books and papers over recent decades attempt to identify ideal educational practices which enable students to better retain material taught in the classroom. From these, numerous conclusions further support a range of influential factors that impact student retention, such as the method of instruction, classroom environmental conditions, relationship dynamics between students and teachers, and assessment or testing patterns. The focus of this study centers on this last factor, testing patterns, and how student retention can be improved in order to better accomplish learning outcomes. In our study, we examine and compare the overall value of periodic open and closed note formative assessments in an engineering course. We analyzed student performance for 202 students enrolled in an undergraduate environmental engineering course that covers several major topics to include environmental engineering fundamentals and chemistry, water and wastewater treatment methods and design, as well as air pollution modeling and control. This semester-long study included a comparison of student performance on major graded events, including midterm and course-end comprehensive examinations along with final term grades between class sections completing open-note, closed-note, and no additional formative assessments. Our study indicates that the type of testing, open versus closed note, did not have a statistically different impact on overall course performance. However, the study did show a statistically significant increase of 2.97-4.87% in course performance and final averages between sections completing either type of periodic testing, versus sections completing no additional testing. This finding suggests that formative assessments not only serve to achieve better retention in an environmental engineering course, but further support current academic literature asserting that testing in the classroom generally results in improved student performance.
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    More than Weather: The Strategic Importance of Remote Environmental Monitoring Capabilities to DOD
    (Small Wars Journal, 2014) Pfluger, Andrew; Wright, William C.
    The Department of Defense (DOD) currently uses several satellite constellations to remotely monitor the environment. One of DOD’s primary interests in environmental monitoring is detecting current weather patterns and discerning how they affect the warfighter. While understanding real-time weather is critical to mission success, understanding long-term environmental impacts from population growth and urbanization, land use change, and climate change is also of critical importance to the strategic vision of the US armed forces. Indeed, many high-ranking officers and military officials have acknowledged that understanding effects from these environmental changes is critical to our nation’s security. A statement by Leon Panetta, former Secretary of Defense, concerning climate change elaborates this point: “The area of climate change has a dramatic impact on national security…rising sea levels, severe droughts, the melting polar caps, the more frequent and devastating natural disasters all raise demand for humanitarian assistance and disaster relief.” In the same speech, Panetta vowed that the Pentagon would take a leading role in combating these changes (Simeone, 2012).
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    Incorporating Structure from Motion from Unmanned Aerial Systems in an Undergraduate Photogrammetry Course
    (American Association for Geodetic Surveying, 2018) Wright, William C.; Oxendine, Christopher; Kerr, Darren J.; Brockhaus, John
    This project sought to develop a replicable learning experience in an undergraduate photogrammetry course that included mission planning, data acquisition, product development, and assessment of the impact of the project on student learning. During the past 2 years, the final project for the course was implemented using a commercial off the shelf Unmanned Aerial System (UAS) to collect imagery at the United States Military Academy (USMA) at West Point, NY, as part of the final project for the course. This teaching approach enabled students to participate in the planning, collection, processing, analysis, and production of a product from start to end. Some of the final project results generated by the students are presented. We have also presented the results from an assessment on how the course and academic program goals were impacted after the implementation of the final project.
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    Course Outcome Assessment: Is Using the Average Good Enough?
    (ASEE Conferences, 2020) Dacunto, Phil; Ng, Andrew
    Assessment of environmental engineering course outcomes is critical for measuring student achievement, evaluating course design, and ultimately assessing programs for ABET accreditation. Often such assessment relies upon the interpretation of results from direct, embedded indicators (graded events such as homework assignments or exams). The simplest approach uses the arithmetic mean of a particular graded event (or set of graded events) to assess the outcome: for example, an average of greater than 80% indicates successful achievement of the outcome. However, such an approach assumes a reasonably normal distribution of student grades, and thus may not be adequately descriptive in some cases. For example, one case where the use of the mean fails is a bimodal distribution of results: if half the students score 100% and half score 60% on a graded event, the resulting mean, 80% (which is generally considered successful) fails to capture the fact that half the students failed. Stoker, Blair, and Sobiesk (2014) proposed a “binning” approach, which accounts for the proportions of students who achieve different levels of success on each assignment; for example, if greater than 5% fail, we assess the outcome to be not successfully achieved, regardless of the overall average. Such an approach, however, is more complicated and time-intensive for faculty to employ. This study investigates the impact of course size (as measured by number of students) on assessment results. Specifically, we present a comparison of course outcome assessment results using both the simpler “mean” and more complicated “binning” approaches for three large (more than 160 students) and two small (less than 35 students) environmental engineering and science courses. The results indicate that the small courses had a greater drop in outcome achievement than the large ones when using the “binning” vs the “mean” approach; however, the "binning" approach could still be useful in these courses with minor modification. In addition, we present some adjustments to the method proposed by Stoker et al. (2014) to make overall outcome assessment more efficient. This study will inform programs as to the conditions under which the more time-intensive “binning” approach is worthwhile, and will enable them to implement the approach more effectively if they so choose. Ref: Stoker, Geoff; Blair, Jean; and Edward Sobiesk. “Meaningful Assessment.” Proceedings of the 15th Annual Conference on Information Technology Education. Atlanta, GA: 15-18 October, 2014.
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    Beer Brewing and the Environmental Engineer: “Tapping” into Experiential Learning
    (ASEE, 2019) Murray, Kyle R.; Wallen, Benjamin M.; Plante, Luke; Quell, Kimberly; Butkus, Michael
    Second to water, beer may perhaps be the next most desirable beverage in the lives of countless environmental engineering students. But do they fully understand or appreciate the engineering and scientific principles behind beer making? While considerable effort has been put forth in academia to teach and explain the critical environmental process of fermentation, too many students are limited to examples and explanations contained within a course textbook. The United States Military Academy is committed to providing experiential learning opportunities that reach beyond traditional classroom instruction. Our Environmental Biological Systems Course (EV396) offers an opportunity for environmental engineers to achieve a deeper, more practical understanding and appreciation for biological systems within our environment. As part of the experiential learning process, EV396 requires students to successfully brew beer in a laboratory setting to enhance their understanding of microbial metabolic processes, disinfection principles, and aseptic techniques. This paper aims to highlight and explain the linkage between the complex process of alcoholic fermentation involved in beer brewing to the environmental engineering practice. Indeed, environmental engineers often face challenges where they must design and operate biological systems and apply engineering concepts like those integral to brewing beer, including conventional wastewater management, microbial fuel cells, hazardous waste treatment and remediation, slow sand filtration, and disinfection. As part of this fermentation laboratory experience, students select the style of beer they wish to brew and exercise the engineered techniques required to brew a safe and refreshing product. Additionally, students are required to submit a detailed report demonstrating their ability to identify and evaluate key physiochemical and biochemical engineering processes. Calculations involve fermentation efficacy, specific gravity and yield, theoretical and actual ethanol content, and scaling from bench experiments to commercial production. The laboratory familiarizes students with engineering concepts, including substrates that serve as carbon and energy sources, methods for creating anaerobic reactors, and solid-liquid separation processes. Using the 5-point Likert scale, with 5 indicating greatest achievement, student laboratory performance scores are consistently greater than 3 and many are above 4, indicating effective learning, application, and understanding. Historical assessment and evaluation of how well this experiential learning laboratory supports course objectives and ABET Student Outcomes and Program Criteria are discussed in detail.
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    More than Weather: The Strategic Importance of Remote Environmental Monitoring Capabilities to DOD
    (Small Wars Journal, 2014) Pfluger, Andrew; Wright, William C.
    The Department of Defense (DOD) currently uses several satellite constellations to remotely monitor the environment. One of DOD’s primary interests in environmental monitoring is detecting current weather patterns and discerning how they affect the warfighter. While understanding real-time weather is critical to mission success, understanding long-term environmental impacts from population growth and urbanization, land use change, and climate change is also of critical importance to the strategic vision of the US armed forces. Indeed, many high-ranking officers and military officials have acknowledged that understanding effects from these environmental changes is critical to our nation’s security. A statement by Leon Panetta, former Secretary of Defense, concerning climate change elaborates this point: “The area of climate change has a dramatic impact on national security…rising sea levels, severe droughts, the melting polar caps, the more frequent and devastating natural disasters all raise demand for humanitarian assistance and disaster relief.” In the same speech, Panetta vowed that the Pentagon would take a leading role in combating these changes (Simeone, 2012).
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    The Five-minute Adsorption Demonstration
    (ASEE, 2020) Butkus, Michael; Shetty, Anand; Wallen, Benjamin; Sheehan, Nathaniel; Pfluger, Andrew
    Adsorption is one of the most common physicochemical treatment processes in environmental engineering. Faculty typically teach this process by explaining figures and equations in texts, which can limit learning. The five minute classroom demonstration presented here replicates the adsorption experiment and data analysis, which may engage students and enhance learning without imposing substantial demands on student time. Students observe removal of Crystal violet dye or food coloring by activated carbon in real time in a column demonstration. Simultaneously, data from an adsorption experiment is collected in an accelerated video format and an animated PowerPoint presentation illustrates how experimental data is used to quantify Isotherm Model parameters. Results from the Crystal violet adsorption experiment and isotherm model parameters are presented along with an in-class example problem.
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    Use of X-Ray Fluorescence to Expedite Sampling to Evaluate and Visualize Soil Lead Concentrations at West Point, NY
    (IEEE, 2020) Wallen, Benjamin; Kimball, M. A.; Wright, William C.; Sheehan, N. P.; Flagg, T. D.; Avellaneda-Ruiz, A. R.; Bier, P.V.
    The concentration of heavy metals, specifically lead, in soil may create unsafe environmental conditions. Unsafe conditions may occur based upon previous exposure to lead, such as particulate pollution from leaded gasoline. Accumulation of lead in the soil is especially concerning due to the detrimental physiological effects soil lead has on populations within residential neighborhoods. This study investigates the efficacy of an X-ray fluorescence (XRF) sensor compared to use of an inductively coupled plasma (ICP) laboratory instrument to measure soil lead concentration through a comparison of 87 soils samples. Findings note a strong correlation between both measurement methods. Additionally, 206 samples were evaluated to visualize soil lead concentrations throughout the residential West Point area. The highest soil lead concentrations are along the former route 9W, at locations associated with buildings that pre-date 1940.
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    Location, Location, Location: The Value of Disciplinary Adjacency in Enhancing Environmental Engineering Programs
    (ASEE, 2019) Dacunto, Phil; Butkus, Michael
    Since the field was largely born out of civil engineering, most of the initial environmental engineering degree-granting programs began in civil engineering departments. Many have stayed there. However, 10 of the last 25 environmental engineering programs accredited by ABET have emerged in other departments. The rationale for aligning environmental engineering programs with other disciplines can be based on numerous factors including diversity of perspectives within the department, collaboration opportunities, facilities requirements, and efficiency. This study examines the distribution of ABET-accredited environmental engineering programs across departments, to include specific program adjacencies and trends over time. In addition, the study examines faculty perspectives on the departmental alignment of environmental engineering programs, to include the faculty’s overall satisfaction with their program’s adjacencies, and the advantages and disadvantages of its particular alignment. Furthermore, it examines faculty perspectives on the program adjacencies that they believe would be most useful, as well as the reasons why. These faculty perspectives can be used to inform the actions of academic institutions who are forming new environmental engineering programs, or those considering a program realignment. In addition, they can inform faculty in existing programs of potential inter-program collaborative possibilities, regardless of which department currently houses their program.
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    Investigation of Diurnal Fluctuations of Heat and Water Distributions Around Landmines Impacted by Soil Heterogeneity
    (IEEE, 2020) Wallen, Benjamin; Wright, William C.; Oxendine, Christopher
    The environment in which landmines are placed is heterogeneous. Such differences in soil type, packing and moisture, combined with changes in surface and climate conditions can oftentimes mask the presence of a mine. Understanding the impact of heterogeneity on heat and mass transfer behavior near landmines is paramount to properly identifying landmine locations for demining operations. This study investigates the impact of soil heterogeneity on soil moisture and temperature distributions around buried objects to increase understanding of environmental conditions most dynamic to mine detection performance. A ten-day field experiment was conducted with sensors monitoring atmospheric, surface, and subsurface conditions relative to four different conditions associated with landmine emplacement. Experimental results demonstrate distinct behaviors in soil moisture and temperature distributions above and around buried objects that change due to soil heterogeneity and different climate conditions (i.e., temperature and rain events).
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    Technical Communications in an Environmental Engineering Curriculum: A Framework for Analysis and Continual Improvement
    (ASEE, 2020) McCollum, Caleb; Pfluger, Andrew; Butkus, Michael
    The ability to effectively communicate technical information is an important skill for engineers, especially young engineers entering the workforce upon completion of their education. Undergraduate environmental engineering programs normally address technical communications, but some do not provide intentionally placed discipline-specific technical communication experiences designed to progressively increase communication skills through the curriculum. Conducting a crosswalk of graded events with a technical communication component across a curriculum can help an institution understand the placement of technical communication graded events and identify opportunities for improvement. This study presents a survey-based approach for gathering information about all technical communication graded events within an environmental engineering curriculum and a method for analysis using a longitudinal crosswalk of all applicable courses from freshman to senior year. Results from this study indicate that the number of graded technical communication events in our program increases longitudinally from freshman to senior year. Further, the number of individually completed events and written events were highest in the sophomore year, with team events and oral communication events increasing in the junior and senior years. Additionally, the weighting of graded events shifted longitudinally through major courses. Graded events worth 5% of the course grade were most prevalent in the sophomore year, and events worth ≥ 5% occurred most frequently in the senior year. Implications for our university’s environmental engineering program are discussed, to include opportunities for scaffolding events across courses. The methods presented in this study can be used by other environmental engineering programs to identify gaps in technical communication education and methods for improvement within their curriculum.
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    Streamlining Experiment Projections For Resolute Bay Incoherent Scatter Radar (risr) To Facilitate Research Of Space Weather Driven Global Positioning System Scintillations
    (IEEE, 2021) Hoxeng, Adam; Loucks, Diana; Wright, William C.; Oxendine, Christopher
    Global navigation satellite system (GNSS) signals are used throughout the world for position, navigation, and timing. As these signals travel to Earth's surface from Medium Earth Orbit they can encounter ionospheric scintillation caused by ionospheric plasma irregularities, especially at high latitudes. This ionospheric scintillation is detrimental to GNSS signal strength, accuracy, and confidence. Incoherent scatter radars like Resolute Bay Incoherent Scatter Radar (RISR) are excellent tools for measuring the ionospheric conditions that surround the path of incoming GNSS signals. This paper outlines a process that utilizes Systems Toolkit (STK) and Matrix Laboratory (MATLAB) to streamline the process of identifying valid future conjunctions between GPS signals and RISR radar beams to advance study of the impact of ionospheric scintillations on GNSS signals at high latitudes.
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    Prediction of L-band signal attenuation in forests using 3D vegetation structure from airborne LiDAR
    (ISPRS Journal of Photogrammetry and Remote Sensing, 2011) Lui, Pang-Wei; Lee, Heezin; Judge, Jasmeet; Wright, William C.; Slatton, K. Clint
    In this study, we propose a novel method to predict microwave attenuation in forested areas by using airborne Light Detection and Ranging (LiDAR). While propagating through a vegetative medium, microwave signals suffer from reflection, absorption, and scattering within vegetation, which cause signal attenuation and, consequently, deteriorate signal reception and information interpretation. A Fresnel zone enveloping the radio frequency line-of-sight is applied to segment vegetation structure occluding signal propagation. Return parameters and the spatial distribution of vegetation from the airborne LiDAR inside Fresnel zones are used to weight the laser points to estimate directional vegetation structure. A Directional Vegetation Density (DVD) model is developed through regression that links the vegetation structure to the signal attenuation at the L-band using GPS observations in a mixed forest in North Central Florida. The DVD model is compared with currently-used empirical models and obtained better R2 values of 0.54 than the slab-based models. Finally, the model is evaluated by comparing with GPS observations of signal attenuation. An overall root mean square error of 3.51 dB and a maximum absolute error of 9.38 dB are found. Sophisticated classification algorithms and full-waveform LiDAR systems may significantly improve the estimation of signal attenuation.
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    Long-term Impact on Environmental Attitudes and Knowledge Assessed over Three Semesters of an Environmental Engineering Sequence
    (ASEE, 2019) Wallen, Benjamin; Sheehan, Nathaniel; Plante, Luke; Martinez, Erick; Starke, Jeffrey
    The pedagogy employed in a three-course environmental engineering sequence is investigated to determine the efficacy of enabling long-term improvement of knowledge and attitudes toward the environment. These three courses incorporate concepts of the five grand challenges released by the National Academy of Engineering and National Academy of Sciences and increase the breadth of knowledge for T-professionals. Previous studies of lengths from a few weeks to semester long courses evaluated the potential causality among various demographics and environmental knowledge and attitudes. The research presented herein contrasts and compares changes in environmental knowledge based upon a 12-question survey and changes in environmental attitude based upon a seven-question survey administered at the beginning and end of the environmental engineering sequence courses taught to over 200 students from a variety of disciplines. Survey results demonstrate that a positive increase (9.27%) in knowledge occurred from the start to the end of the first course and the elimination of statistical differences among numerous demographics such as sex and race. After 18 months of environmental education, an 8.6% increase in knowledge was retained compared to the initial knowledge where the female and non-white demographics increased the most but retained the least. Results regarding environmental attitudes suggest that a focus on learning about environmental issues decreased positive attitudes toward the environment, whereas focusing on solutions to environmental issues increased positive attitudes toward the environment. Evaluating changes or sustainment of improved environmental attitudes over three semesters demonstrates the potential for an environmental engineering education to have a multi-year impact on the values and environmental ethos of students across many disciplines.
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    Predicting L-band Microwave Attenuation through Forest Canopy using Directional Structuring Elements and Airborne Lidar
    (IEEE, 2008) Wright, William C.; Lui, Pang-Wei; Slatton, K. Clint; Shrestha, R. L.; Carter, W.E.; Lee, Heezin
    The L-band signals broadcast by GPS satellites are attenuated by vegetation, making it problematic, if not impossible, to predict the performance of the system in forested areas without some quantitative measure of the structure and density of the local forest canopy. Airborne laser swath mapping (ALSM) observations can be used to rapidly and remotely sample the structure and density of forested areas. We report here the results of a study performed to determine the attenuation of GPS signals in forests, by correlating changes in the signal-to-noise ratio (SNR) of the received GPS signals under different canopies, using three dimensional structure and density information about each canopy derived from ALSM observations. The results of this study verify that the loss of signal is strongly correlated with the local structure and density of the forest, and we demonstrate how the ALSM point cloud can be used to better predict the attenuation of the GPS signals. The results of this research also pertain to other modes of microwave transmission in forested areas, including satellite and cellular telephony, and the estimation of biomass from L-band radar.
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    Sea ice detection from persistent single-channel shortwave infrared satellite data
    (Ecological Informatics, 2019) Lewis, Nicholas S.; Koenig, Lora; Grant, Glenn; Gallaher, David; Schaefer, Kevin; Thompson, Jeffery; Campbell, G. Garrett
    The US Air Force has demonstrated an interest in deriving imagery products from classified military remote sensing platforms and making them available for civil and commercial operations. The US Air Force's Overhead Persistent Infrared (OPIR) is one such satellite constellation. A novel aspect of OPIR imagery is its near-continuous capture of single channel shortwave infrared data over the Arctic. Although traditionally used for missile warning and strategic defense, the exceptionally high temporal resolution of the OPIR data stream makes it an attractive source for Arctic remote sensing, particularly as the Arctic has warmed at a rate nearly double that of lower latitudes. This work assesses the feasibility of using Geostationary Operational Environmental Satellite – 16 (GOES-16) data as a proxy for OPIR imagery in the Arctic. Specifically, we seek to determine whether a single channel shortwave infrared (SWIR) approach can be used to detect and chart Arctic sea ice. We used a series of 32-image daily sets (4 images per hour x 8 h) over four-day periods acquired by GOES-16 in late April 2016 (as well as mid-March, mid-May, and mid-June) to chart sea ice, clouds and water in Hudson Bay, Canada. To do this, we applied image enhancement techniques to raw data imagery and then employed a time-based classification algorithm to the enhanced data cube. Overall, our method successfully discriminated sea ice from water and clouds when all conditions were present with improved discrimination over current daily products for sea ice charting in the Northern Hemisphere. The simple methodology of the developed algorithm is critical to ensuring the temporal resolution of the sensor is capitalized. The rapid timeline for production of this type of data is essential to the relevancy to military operations as well as emergency response/preparedness operations in the Arctic as it becomes more accessible in coming years. Our results make a compelling argument for the application of Air Force Missile Warning data to assist in the mapping, tracking, and assessment of sea ice in the high Arctic.
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    Estimating signal loss in pine forests using hemispherical sky oriented photos
    (Ecological Informatics, 2017) Wright, William C.; Wilkinson, Benjamin E.; Cropper, Wendell P.
    We depend on numerous technologies that use microwave signals. The reception of these signals is degraded by reflection, absorption, and scattering due to propagation through vegetation. An understanding of how these signals are influenced by vegetation structure allows for the determination of how specific technologies may be affected in certain forest environments. This study presents a model that predicts signal loss in forested areas using novel methods. We explore the relationships between forest parameters from traditional mensuration techniques and terrestrial-based hemispherical sky oriented photos (HSOPs), and GPS signal-to-noise ratios (SNRs). HSOPs can be used to rapidly estimate leaf area index (LAI) and canopy closure (CC) values at particular angles from zenith in forested areas. The relationships between changes in the observed SNR of received GPS L1-band signals under forest canopies and forest parameter estimates calculated using HSOPs and traditional forest measurements are used to model signal attenuation. Using ordinary least squares regression modeling, we present the Canopy Closure Predictive Model (CCPM). The CCPM outlines the key forest parameters used with an adjusted R2 of 0.71 and RMSE of 2.78 dB. The resulting CCPM predicts signal attenuation while using only the minimum number of statistically-significant parameters which, conveniently, are taken from sky oriented photos and GPS receivers allowing for simple and rapid replication.
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    Evaluating the relationship between data resolution and the accuracy of identified helicopter landing zones (HLZs)
    (Applied Geography, 2022) Erskine, John; Oxendine, Christopher; Wright, William C.; O'Banion, Matthew S.; Philips, Andrew
    Helicopters provide critical advantages in military operations because of their ability to land at small and unimproved sites. While the military uses models to identify helicopter landing zones (HLZs), little research has been conducted on their accuracy. This study evaluated the performance of an HLZ detection model derived from existing selection criteria that incorporated elevation and land cover data with spatial resolutions ranging from 1 m to 30 m. Multiple HLZs were selected as study sites at three geographically varied locations. The HLZ boundaries identified using the derived model were then compared to surveyed reference boundaries to assess their accuracy. This study found that as the spatial resolution of the data became coarser, accuracy decreased across all sites. However, there were some instances where noticeable increases in error were observed at certain resolutions for some sites. The resolution at which this occurred was always related to the size of features either bounding or located within the landing area. Thus, this study found that the most important consideration when determining ideal resolution for HLZ detection is the geography of the study area. While additional research is needed, this study presents initial findings and a framework upon which future assessments can build.
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    Effects of location, classroom orientation, and air change rate on potential aerosol exposure: an experimental and computational study
    (Environmental Science: Processes & Impacts, 2022) Dacunto, Phil; Ng, Andrew; Moser, D.; Tovkach, A.; Scanlon, S.; Benson, Michael J.
    This study examined the dispersion of potentially infectious aerosols in classrooms by means of both a CO2 tracer gas, and multizone contaminant transport modeling. A total of 20 tests were conducted in three different university classrooms at multiple air change rates (4.4–9.7/h), each with two different room orientations: one with the tracer gas released from six student desks toward the air return, and one with the same tracer gas released away from it. Resulting tracer concentrations were measured by 19 different monitors arrayed throughout the room. Steady-state, mean tracer gas concentrations were calculated in six instructor zones (A–F) around the periphery of the room, with the results normalized by the concentration at the return, which was assumed to be representative of the well-mixed volume of the room. Across all classrooms, zones farthest from the return (C, D) had the lowest mean normalized concentrations (0.75), while those closest to the return (A, F) had the highest (0.95). This effect was consistent across room orientations (release both toward and away from the return), and air change rates. In addition, all zones around the periphery of the room had a significantly lower concentration than those adjacent to the sources. Increasing the ventilation rate reduced tracer gas concentrations significantly. Similar trends were observed via a novel approach to CONTAM modeling of the same rooms. These results indicate that informed selection of teaching location within the classroom could reduce instructor exposure.
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    Engaging Students Through an Interactive Mass Balance Fundamentals Demonstration
    (ASEE, 2020) Wallen, Benjamin; Butkus, Michael; Sheehan, Nathaniel; Ng, Andrew; Pfluger, Andrew
    Employing mass balance concepts is one of the fundamental approaches to address many of the National Academy of Engineering’s Grand Challenges of the 21st century. Of the five stated grand challenges, the incorporation of mass balance principles is central to understanding and resolving four of the five technical challenges while it supports and informs decision making in the fifth. For burgeoning environmental engineers, the understanding of mass balance concepts is foundational for recognizing and solving the complex multimedia environmental problems they will face. Environmental engineering curricula therefore requires students to fully understand and demonstrate proficiency in the application of mass balance concepts. Unfortunately, many students struggle to initially visualize key aspects and understand assumptions used with the mass balance approach. A five-minute demonstration provides a visual, interactive classroom experience that improves understanding and learning for a broad spectrum of students’ learning style preferences. The approach presented in this paper has been successfully used in an introductory environmental engineering course taught predominantly to non-engineering majors as part of a three-course environmental engineering sequence. Current data suggests that the incorporation of this demo improves student understanding of mass balance concepts evidenced by improved quantitative testing scores over the past two years. Though longitudinal data is forthcoming on the efficacy on long term retention, we strive for each non-engineering major in the sequence to be able to more broadly contextualize and solve complex problems using mass balance principles by incorporating a deliberate systematic approach. Indeed, for our students to tackle the grand challenges of this century, they must be able to understand the inherent interconnectedness of global and regional environmental systems.