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Old Dominion University

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Articles 31 - 60 of 540

Full-Text Articles in Civil and Environmental Engineering

Low Dissolved Oxygen Operation Enhances Biological Phosphorus Removal In Wastewater Treatment, Haley Morgan Apr 2025

Low Dissolved Oxygen Operation Enhances Biological Phosphorus Removal In Wastewater Treatment, Haley Morgan

Civil & Environmental Engineering Theses & Dissertations

Biological phosphorus (bio-P) removal occurs when bacteria are exposed to anaerobic/aerobic conditions that stimulate polyphosphate-accumulating organisms (PAOs) to uptake phosphorus. In most treatment plants, dissolved oxygen (DO) concentrations in the aeration tanks are commonly at or above 2.0 mg O2/L, which is often referred to as the most optimal aeration condition for bio-P. If bio-P can happen efficiently at lower DO (< 0.3 mg O2/L), then the energy demand of aeration can be decreased appreciably. This research was conducted in a biological nutrient removal (BNR) pilot plant to assess the performance of bio-P at progressively lower DO operation. This …

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Modeling The Impacts Of Disruptive Events On Driving Behaviors, Transportation Safety, And Equity: Advanced Statistical Insights From The Covid-19 Pandemic, Xiaomeng Dong Apr 2025

Modeling The Impacts Of Disruptive Events On Driving Behaviors, Transportation Safety, And Equity: Advanced Statistical Insights From The Covid-19 Pandemic, Xiaomeng Dong

Civil & Environmental Engineering Theses & Dissertations

This dissertation aims to understand how disruptive events —particularly the COVID-19 pandemic—affect driving behaviors, transportation safety and equity by leveraging advanced statistical modeling techniques and data from Virginia. This research pursues three overarching objectives. First, it employs multigroup structural equation modeling (SEM) to uncover the complex interrelationships among risky driving behaviors, injury severity, and pandemic-related factors, delineating the mechanisms through which COVID-19 has impacted crash outcomes via changing risky driving behaviors. Second, it leverages hidden Markov models to trace shifts in safety states over the pre-, during-, and post-pandemic periods, determining whether and when safety conditions return to pre-pandemic norms. …

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Estimating Depth Of Roadway Flooding Using Data From Lidar And Surveillance Cameras, Mahta Zamanizadeh, Mecit Cetin Feb 2025

Estimating Depth Of Roadway Flooding Using Data From Lidar And Surveillance Cameras, Mahta Zamanizadeh, Mecit Cetin

Graduate Student Government Association Research Conference

In this study, we fuse data from a 3D LIDAR mounted on a vehicle and images from an external traffic surveillance camera to create a 3D representation of a segment of a roadway that experiences frequent flooding. The point cloud data from the LiDAR in this study is collected from a road segment of W 49th Street in Norfolk, near the ODU campus. The traffic surveillance camera is mounted on a public parking building in the same area. The LiDAR collects continuous point cloud frames as the vehicle traverses the section. Multiple LIDAR frames related to the respective segment …

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Rapid Prediction Of Coastal Flooding With Deep Neural Networks, Ali Shahabi, Navid Tahvildari Feb 2025

Rapid Prediction Of Coastal Flooding With Deep Neural Networks, Ali Shahabi, Navid Tahvildari

Graduate Student Government Association Research Conference

With the increasing impact of climate change and relative sea level rise, low-lying coastal communities face growing risks from extreme storm tides and recurrent nuisance flooding. Thus, timely and reliable predictions of coastal water levels are critical to resilience in vulnerable coastal areas. Over the past decade, enormous efforts have been made to utilize machine learning (ML) based data-driven models for the emulation and prediction of storm tides. However, flood advisory systems still rely on running computationally demanding real-time hydrodynamic models. because developing highly reliable ML-based models suitable for real-time forecasting and capable of capturing any surge levels is challenging. …

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A Bridge Too Low, John Adam Jan 2025

A Bridge Too Low, John Adam

Mathematics & Statistics Faculty Publications

The article "A bridge too low" in the Physics Teacher journal discusses a low bridge near the River Greta in Keswick, England, with an arch shaped like a semiellipse. It presents questions about the maximum height a person of a certain height can walk under the bridge without hitting their head, the cross-sectional area of the arch, its eccentricity, and perimeter. The article also mentions the approximation by Indian mathematician Srinivasa Ramanujan for the perimeter of an ellipse and invites readers to find the answers online.

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Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park Jan 2025

Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park

Engineering Management & Systems Engineering Faculty Publications

Traditionally, traffic incident management (TIM) programs coordinate the deployment of emergency resources to immediate incident requests without accommodating the interdependencies on incident evolutions in the environment. However, ignoring these inherent interdependencies while making current deployment decisions is shortsighted, and the resulting naive deployment strategy can significantly worsen the overall incident delay impact on the network. The interdependencies on incident evolution in the environment, including those between incident occurrences and those between resource availability in near-future requests and the anticipated duration of the immediate incident request, should be considered through a look-ahead model when making current-stage deployment decisions. This study develops …

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Human Perception Of Ai Capabilities At Classifying Perturbed Roadway Signs, Katherine R. Garcia, Jing Chen, Yanru Xiao, Scott Mishler, Cong Wang, Bin Hu Jan 2025

Human Perception Of Ai Capabilities At Classifying Perturbed Roadway Signs, Katherine R. Garcia, Jing Chen, Yanru Xiao, Scott Mishler, Cong Wang, Bin Hu

Psychology Faculty Publications

Artificial Intelligence (AI) is crucial to numerous functions required for driving automation systems, including the computer vision techniques used to detect the roadway environment and make real-time decisions. However, the images used as inputs to the AI system may be maliciously perturbed, or manipulated, causing the AI system to make an incorrect classification. In this study, we examined humans’ perception of the AI’s computer vision capability of classifying various road sign images, including the original images, images with two different types of malicious attacks, and images that are scrambled randomly at the pixel level. Our results showed that participants rated …

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Tidal Flooding Contributes To Eutrophication: Constraining Nonpoint Source Inputs To An Urban Estuary Using A Data Driven Statistical Model, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Sophie Clayton, Peter W. Bernhardt, Thomas R. Allen Jan 2025

Tidal Flooding Contributes To Eutrophication: Constraining Nonpoint Source Inputs To An Urban Estuary Using A Data Driven Statistical Model, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Sophie Clayton, Peter W. Bernhardt, Thomas R. Allen

OES Faculty Publications

In coastal urban areas, tidal flooding brings water carrying nutrients and particles back from land to estuarine and coastal waters. A statistical model to predict nutrient loads during tidal flooding events can help estimate nutrient loading from previous and future flooding events and adapt nutrient reduction strategies. We measured concentrations of dissolved inorganic nitrogen and phosphorus in floodwater at seven sentinel sites during 15 tidal flooding events from January 2019 to September 2020. The study area was the Lafayette River watershed in Norfolk, VA, USA, which is prone to tidal flooding and is predicted to experience more frequent and intense …

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The Bioremediation Of Nutrients And Heavy Metals In Watersheds: The Role Of Floating Treatment Wetlands, Nirmal Kumar, Bhupinder Singh, Yuanze Chen, Abishek Kafle, Ram L. Ray, Sandeep Kumar, Xiaonan Shan, Venkatesh Balan Jan 2025

The Bioremediation Of Nutrients And Heavy Metals In Watersheds: The Role Of Floating Treatment Wetlands, Nirmal Kumar, Bhupinder Singh, Yuanze Chen, Abishek Kafle, Ram L. Ray, Sandeep Kumar, Xiaonan Shan, Venkatesh Balan

Civil & Environmental Engineering Faculty Publications

Floating treatment wetlands (FTWs) are engineered systems that utilize floating platforms planted with aquatic vegetation to treat polluted water such as stormwater, agricultural runoff, and wastewater. FTWs have emerged as promising and environmentally sustainable solutions for water purification. This review synthesizes the current knowledge on FTW design, plant selection, and performance evaluation. It highlights key factors influencing nutrient and heavy metal removal, including the hydraulic retention time, mat thickness, and types of plant species. Recent findings on the roles of root architecture, microbial interactions, and seasonal variability in treatment efficiency are also discussed. Additionally, the review explores advanced analytical methods …

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A Blueprint To Greener Shorelines: Advancing The Effectiveness, Sustainability, And Widespread Adoption Of Coastal Nature-Based Solutions Through Transdisciplinary Research, Taylor M. Sloey, Sierra Hildebrandt, Rebecca L. Morris, Matthew V. Bilskie, Aaron Bland, David Bushek, Gabriella Dipetto, Daniel Elefant, Vincent Encomio, Ramin Familkhalili, Christine Hladik, Danielle Kreeger, Avery B. Paxton, Cindy M. Palinkas, Latina Steele, Andrew Scheld, Daisuke Taira, Jason D. Toft, Armando J. Ubeda, Christine Whitcraft, Donna Marie Bilkovic Jan 2025

A Blueprint To Greener Shorelines: Advancing The Effectiveness, Sustainability, And Widespread Adoption Of Coastal Nature-Based Solutions Through Transdisciplinary Research, Taylor M. Sloey, Sierra Hildebrandt, Rebecca L. Morris, Matthew V. Bilskie, Aaron Bland, David Bushek, Gabriella Dipetto, Daniel Elefant, Vincent Encomio, Ramin Familkhalili, Christine Hladik, Danielle Kreeger, Avery B. Paxton, Cindy M. Palinkas, Latina Steele, Andrew Scheld, Daisuke Taira, Jason D. Toft, Armando J. Ubeda, Christine Whitcraft, Donna Marie Bilkovic

Biological Sciences Faculty Publications

Coastal nature-based solutions (NbS) have emerged as powerful tools to enhance sustainable development and ecological restoration goals. As a rapidly growing field spanning across social, political, ecological, economic, and engineering disciplines, it is critical that researchers working in coastal NbS regularly attempt to identify emerging focal areas for scientific inquiry. Following the 27th Biennial meeting of the Coastal and Estuarine Research Federation, we provide a transdisciplinary perspective (including biologists, engineers, oceanographers, geoscientists, economists, and facilitators of workforce training programs) of pertinent research questions that, if answered, will advance the effectiveness, sustainability, and widespread adoption of coastal NbS. These suggestions for …

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Integrated Valuation Of The Ecological, Social And Economic Benefits Provided By A Multifunctional Nature-Based Solution, Laura Costadone, Shan Zhang Jan 2025

Integrated Valuation Of The Ecological, Social And Economic Benefits Provided By A Multifunctional Nature-Based Solution, Laura Costadone, Shan Zhang

ODU Articles

Nature-based Solutions (NbS) offer multifunctional approaches to address climate change and environmental challenges, providing a sustainable alternative to traditional gray infrastructure. Despite their promise, widespread adoption remains limited, in part due to an incomplete understanding of their full costs and benefits relative to conventional infrastructure. Traditional benefit–cost analyses often overlook non-monetized benefits and the interconnected ecosystem services provided by NbS. This study introduces a methodological approach to quantify both the physical and monetary value of ecosystem services and co-benefits delivered by an NbS project. We applied an integrated valuation framework to a case study in Virginia Beach, VA, USA, where …

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Long-Term Traffic Prediction Using Deep Learning Long Short-Term Memory, Ange-Lionel Toba, Sameer Kulkarni, Wael Khallouli, Timothy Pennington Jan 2025

Long-Term Traffic Prediction Using Deep Learning Long Short-Term Memory, Ange-Lionel Toba, Sameer Kulkarni, Wael Khallouli, Timothy Pennington

School of Cybersecurity Faculty Publications

Traffic conditions are a key factor in our society, contributing to quality of life and the economy, as well as access to professional, educational, and health resources. This emphasizes the need for a reliable road network to facilitate traffic fluidity across the nation and improve mobility. Reaching these characteristics demands good traffic volume prediction methods, not only in the short term but also in the long term, which helps design transportation strategies and road planning. However, most of the research has focused on short-term prediction, applied mostly to short-trip distances, while effective long-term forecasting, which has become a challenging issue …

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Applying Transfer Learning For Street-Scale Nuisance Flood Forecasting In Coastal-Urban Cities, Binata Roy, Jonathan L. Goodall, Diana Mcspadden, Chetan Kumar, Steven Goldenberg, Yidi Wang, Malachi Schram Jan 2025

Applying Transfer Learning For Street-Scale Nuisance Flood Forecasting In Coastal-Urban Cities, Binata Roy, Jonathan L. Goodall, Diana Mcspadden, Chetan Kumar, Steven Goldenberg, Yidi Wang, Malachi Schram

VMASC Publications

An important challenge with Machine Learning (ML) is its transferability; i.e., whether a ML model trained on one set of data can be applied to a second set of data without requiring full re-training of the model. Transfer Learning (TL) addresses this challenge by transferring knowledge learned in the source domain (the data it was trained on) to the target domain (a second set of data that is statistically different but related, which the model was not trained on). This study investigates the use of TL for street-scale nuisance flood forecasting by exploring whether a ML model trained for one …

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Green Chelation Strategy For Deashing Of Algal Biomass, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar Jan 2025

Green Chelation Strategy For Deashing Of Algal Biomass, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

This study investigated a green chelation strategy for deashing algal biomass using nitrilotriacetic acid (NTA) and deionized water (DI) to enhance its suitability for biofuel and bioproduct applications. Solid-state algal turf scrubber (SS ATS), green algal turf scrubber (ATS), and Scenedesmus were analyzed, with Scenedesmus selected for detailed evaluation due to its high ash removal efficiency. The objective was to optimize a purification process that minimizes ash and heavy metal content while preserving biochemical integrity. Algal biomass underwent sequential washing with DI, NTA, and NTA+DI under varying temperatures (90-130 °C). Analytical techniques including Fourier Transform Infrared (FTIR) spectroscopy, Inductively Coupled …

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Social Susceptibility-Driven Longitudinal Tornado Reconnaissance Methodology: 2021 Midwest Quad-State Tornado Outbreak, John W. Van De Lindt, Wanting "Lisa" Wang, Blythe Johnston, P. Shane Crawford, Guirong Yan, Thang Dao, Trung Do, Katie Skakel, Mojtaba Harati, Tu Nguyen, Robinson Umeike, Silvana Croope Jan 2025

Social Susceptibility-Driven Longitudinal Tornado Reconnaissance Methodology: 2021 Midwest Quad-State Tornado Outbreak, John W. Van De Lindt, Wanting "Lisa" Wang, Blythe Johnston, P. Shane Crawford, Guirong Yan, Thang Dao, Trung Do, Katie Skakel, Mojtaba Harati, Tu Nguyen, Robinson Umeike, Silvana Croope

Civil & Environmental Engineering Faculty Publications

With the impact of climate change, the intensity and frequency of tornado events have been increasing. Enhancing tornado reconnaissance methods can comprehensively capture building damage and recovery data following tornado events and outbreaks, thereby strengthening community resilience against the threat of future tornado events. Advancements in tornado data reconnaissance research have embraced remote sensing techniques to assess building damage after tornado events, supplanting traditional reconnaissance methods relying on handheld cameras with GIS mapping. Community resilience research offers a groundbreaking perspective, stressing the importance of assessing buildings throughout their recovery cycle-from damage and functionality to recovery-and considering their socioeconomic stability in …

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Biochar For Soil Amendment: Applications, Benefits, And Environmental Impacts, Ujjwal Pokharel, Gururaj Neelgund, Ram L. Ray, Venkatesh Balan, Sandeep Kumar Jan 2025

Biochar For Soil Amendment: Applications, Benefits, And Environmental Impacts, Ujjwal Pokharel, Gururaj Neelgund, Ram L. Ray, Venkatesh Balan, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

The excessive use of chemical fertilizers results in environmental issues, including loss of soil fertility, eutrophication, increased soil acidity, alterations in soil characteristics, and disrupted plant–microbe symbiosis. Here, we synthesize recent studies available from up to 2025, focusing on engineered biochar and its application in addressing issues of soil nutrient imbalance, soil pollution from inorganic and organic pollutants, soil acidification, salinity, and greenhouse gas emissions from fields. Application of engineered biochar enhanced the removal of Cr (VI), Cd²+, Ni²+, Zn²+, Hg²+, and Eu³+ by 85%, 73%, 57.2%, 12.7%, 99.3%, and 99.2%, …

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A Global Application Programming Interface-Enabled Earthquake Ground Motion Relational Database For Engineering Applications, Tristan E. Buckreis, Chukwuebuka C. Nweke, Pengfei Wang, Scott J. Brandenberg, Maria E. Ramos-Sepúlveda, Rashid Shams, Shako Mohammed, Renmin Pretell, Silvia Mazzoni, Paolo Zimmaro, Jonathan P. Steward Jan 2025

A Global Application Programming Interface-Enabled Earthquake Ground Motion Relational Database For Engineering Applications, Tristan E. Buckreis, Chukwuebuka C. Nweke, Pengfei Wang, Scott J. Brandenberg, Maria E. Ramos-Sepúlveda, Rashid Shams, Shako Mohammed, Renmin Pretell, Silvia Mazzoni, Paolo Zimmaro, Jonathan P. Steward

Civil & Environmental Engineering Faculty Publications

We present a application programming interface (API)-enabled relational database of global earthquake ground motion intensity measures, associated metadata, and processed time-series data. Raw ground motion records were processed by the authors using either manual or semi-automated processing procedures, and every processed record has passed a quality review by a trained analyst. Computed intensity measures include peak acceleration and velocity, pseudo-spectral acceleration response spectra, cumulative absolute velocity, Arias Intensity, and Fourier amplitude spectra. The processed time-series data, associated metadata, and ground motion intensity measures were organized into a web-served relational database consisting of 32 tables connected by primary/foreign key pairs. Ground …

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Environmentally Friendly Chelation For Enhanced Algal Biomass Deashing, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar Jan 2025

Environmentally Friendly Chelation For Enhanced Algal Biomass Deashing, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

High ash content in algal biomass limits its suitability for biofuel production by reducing combustion efficiency and increasing fouling. This study presents a green deashing strategy using nitrilotriacetic acid (NTA) and deionized (DI) water to purify Scenedesmus algae, which was selected for its high ash removal potential. The optimized sequential treatment (DI, NTA chelation, and DI+NTA treatment at 90–130 °C) achieved up to 83.07% ash removal, reducing ash content from 15.2% to 3.8%. Elevated temperatures enhanced the removal of calcium, magnesium, and potassium, while heavy metals like lead and copper were reduced below detection limits. CHN analysis confirmed minimal …

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Revealing Rainfall Partitioning Characteristics Of Shrubs In Semi-Arid Sandy Land: Based On In-Situ Measurement Data, Hu Liu, Limin Duan, Yongzhi Bao, Xin Tong, Huimin Lei, Zhiming Han, Wenrui Zhang, Xixi Wang, V. P. Singh, Tingxi Liu Jan 2025

Revealing Rainfall Partitioning Characteristics Of Shrubs In Semi-Arid Sandy Land: Based On In-Situ Measurement Data, Hu Liu, Limin Duan, Yongzhi Bao, Xin Tong, Huimin Lei, Zhiming Han, Wenrui Zhang, Xixi Wang, V. P. Singh, Tingxi Liu

Civil & Environmental Engineering Faculty Publications

Rainfall is partitioned by the vegetation canopy into three components: throughfall, stemflow, and canopy interception, which profoundly influence key hydrological processes, including vegetation growth, groundwater recharge, water cycling, and regional water balance. However, research comparing the applicability of throughfall measurement methods in semi-arid shrub communities remains scarce, and quantitative analyses of rainfall partitioning processes based on in-situ observations are still inadequate. This study focuses on the sand-fixing pioneer vegetation of semi-arid sandy land, Caragana microphylla, and conducts simultaneous throughfall measurements using the rain gauge method and the trough method to compare the differences between the two approaches. Based on …

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Sustainable Management Of Erosive Shores: An Interdisciplinary Approach Integrating Engineering And Social Sciences At A Tide-Dominant Beach Area, Jun Ik Sohn, Hyun Dong Kim, Kiran Adhithya Ramakrishnan Jan 2025

Sustainable Management Of Erosive Shores: An Interdisciplinary Approach Integrating Engineering And Social Sciences At A Tide-Dominant Beach Area, Jun Ik Sohn, Hyun Dong Kim, Kiran Adhithya Ramakrishnan

Civil & Environmental Engineering Faculty Publications

This study investigates the causes and consequences of shoreline erosion at Kkotji Beach, a prominent tourist destination on the west coast of South Korea, where the degradation of the coastal environment has increasingly threatened the local tourism industry and economy, by employing a mixed-methods approach that combines field observations with MIKE 21 hydrodynamic simulations and by integrating perspectives from coastal engineering and the social sciences to develop practical, site-specific strategies for mitigating erosion, enhancing public awareness, and promoting sustainable coastal planning and development that support long-term environmental resilience and economic stability. The results show that dominant ebb currents drive southward …

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Laboratory Investigation Of Shape And Initial Orientation Effects On Surf Zone Object Migration, Temitope E. Idowu, Jack A. Puleo Jan 2025

Laboratory Investigation Of Shape And Initial Orientation Effects On Surf Zone Object Migration, Temitope E. Idowu, Jack A. Puleo

Civil & Environmental Engineering Faculty Publications

Discarded objects like munitions in marine environments pose public safety risks. The behavior of various density objects deployed at four cross-shore positions in the surf zone of a large-scale 120 m x 5 m x 5 m wave flume were observed under different forcing conditions. Net migration was predominantly directed offshore, with approximately 70 % offshore migration observed near the outer surf zone. Density, shape, and initial orientation were identified as important to object behavior, with density acting as the dominant driver in 67 % of the object pairing scenarios. The influence of shape and initial orientation on net migration …

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Developing Entrepreneurial Mindsets In Construction Management Through Experiential Projects, Dalya Ismael Jan 2025

Developing Entrepreneurial Mindsets In Construction Management Through Experiential Projects, Dalya Ismael

Engineering Technology Faculty Publications

Entrepreneurial Minded Learning (EML), a framework supported by the Kern Entrepreneurial Engineering Network (KEEN), promotes critical thinking and innovation by encouraging students to explore real-world problems through the 3Cs: Curiosity, Creating Value, and Connections. In construction management education, the focus often remains on technical skills and project execution, neglecting the development of entrepreneurial skills like adaptability, value creation, and stakeholder engagement, leaving a gap in preparing students for the challenges of the industry. To bridge this gap, micro-moment activities were introduced prior to the main project to prime students for EML-based thinking. These short, focused exercises encouraged students to solve …

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Physics-Informed Deep Learning With Kalman Filter Mixture For Traffic State Prediction, Niharika Deshpande, Hyoshin (John) Park Jan 2025

Physics-Informed Deep Learning With Kalman Filter Mixture For Traffic State Prediction, Niharika Deshpande, Hyoshin (John) Park

Engineering Management & Systems Engineering Faculty Publications

Accurate traffic forecasting is crucial for understanding and managing congestion for efficient transportation planning. However, conventional approaches often neglect epistemic uncertainty, which arises from incomplete knowledge across different spatiotemporal scales. This study addresses this challenge by introducing a novel methodology to establish dynamic spatiotemporal correlations that captures the unobserved heterogeneity in travel time through distinct peaks in probability density functions, guided by physics-based principles. We propose an innovative approach to modifying both prediction and correction steps of the Kalman Filter (KF) algorithm by leveraging established spatiotemporal correlations. Central to our approach is the development of a novel deep learning model …

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A Bridge Too Low: Solutions For Fermi Questions, May 2025, John Adam Jan 2025

A Bridge Too Low: Solutions For Fermi Questions, May 2025, John Adam

Mathematics & Statistics Faculty Publications

The article discusses a low bridge in Keswick, England, near the River Greta, with an arch shaped like a semiellipse. It presents Fermi questions related to the bridge's dimensions, such as the maximum distance a person of a certain height can walk under it without hitting their head. The solutions involve mathematical calculations and approximations, including the use of formulas provided by the Indian mathematician Srinivasa Ramanujan.

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The Pluralistic Natural Capital Values Of A Tropical City, Adrienne Grêt-Regamey, Justine Saunders, Peter Edwards, Daniel Richards, Jahson I. Alemu, Natasha Bhatia, Roman Carrasco, Zuzana Drillet, Tze Kwan Fung, Yan Feng Leon Gaw, Wanggi Jaung, Andrea Law, Rachel Ai Ting Leong, Aikeen Youu Ming Lim, Mahyar Masoudi, Yudhishthra Nathan, Rachel Rui Ying Oh, Wen Ting Ooi, Fairul Edros Ahmad Shaikh Shaikh, Xiao Ping Song, Claudia L.Y. Tan, Puay Yok Tan, Sergio Wicki, Lynn-Wei Wong, Yanyun Yan, Erik Yando, Alex Thiam Koon Yee, Jingyuan Zhang, Daniel A. Friess Jan 2025

The Pluralistic Natural Capital Values Of A Tropical City, Adrienne Grêt-Regamey, Justine Saunders, Peter Edwards, Daniel Richards, Jahson I. Alemu, Natasha Bhatia, Roman Carrasco, Zuzana Drillet, Tze Kwan Fung, Yan Feng Leon Gaw, Wanggi Jaung, Andrea Law, Rachel Ai Ting Leong, Aikeen Youu Ming Lim, Mahyar Masoudi, Yudhishthra Nathan, Rachel Rui Ying Oh, Wen Ting Ooi, Fairul Edros Ahmad Shaikh Shaikh, Xiao Ping Song, Claudia L.Y. Tan, Puay Yok Tan, Sergio Wicki, Lynn-Wei Wong, Yanyun Yan, Erik Yando, Alex Thiam Koon Yee, Jingyuan Zhang, Daniel A. Friess

Biological Sciences Faculty Publications

Nature in cities is essential for human well-being. Quantifying and valuing the goods and services provided by nature to city dwellers is missing in tropical contexts. Yet, as cities worldwide face similar challenges, understanding the services provided by tropical urban ecosystems becomes imperative for effective management. Here, we present the first Natural Capital Assessment of a tropical city, unveiling three critical insights. Firstly, we demonstrate the vital reliance of a developed tropical city on nature, particularly for climate change mitigation through regulating services. Secondly, we identify intact natural areas as Singapore’s most valuable assets, stressing the significance of the quality …

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Drone-Based Medication Delivery For Rural, Flood-Prone Coastal Cities, Yin-Hsuen Chen, Amro M. El-Adle, Kevin J. O'Brien, Taylor Wentworth, Heather G. Richter Jan 2025

Drone-Based Medication Delivery For Rural, Flood-Prone Coastal Cities, Yin-Hsuen Chen, Amro M. El-Adle, Kevin J. O'Brien, Taylor Wentworth, Heather G. Richter

Center for Geospatial Science, Education & Analytics Faculty Publications

Access to healthcare remains a critical challenge for rural populations, particularly in flood-prone coastal communities where transportation barriers limit access to essential medical services. This study evaluates the effectiveness of drone-based medication delivery in improving healthcare accessibility for vulnerable populations on Virginia’s Eastern Shore. Compared to traditional personal vehicle travel, drone delivery reduced trip times from up to 50 minutes to under 10 minutes for more than 80% of the population, including elderly patients. Using publicly available datasets, we developed two transportation vulnerability indices that incorporate age, travel time, and flood risk to prioritize patients for drone-based pharmaceutical delivery. These …

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Engagement In Practice: Partnering With Communities To Address Nuisance Flooding Challenges, Carol L. Considine, Mujde Erten-Unal, Dalya Ismael, Luka Alandra Hamal-Serenity, Farzaneh Soflaei Jan 2025

Engagement In Practice: Partnering With Communities To Address Nuisance Flooding Challenges, Carol L. Considine, Mujde Erten-Unal, Dalya Ismael, Luka Alandra Hamal-Serenity, Farzaneh Soflaei

Engineering Technology Faculty Publications

Many communities are already experiencing the impacts of climate change that disrupt their daily lives. In Coastal Virginia, these impacts take the form of nuisance and stormwater flooding caused by sea level rise and changes in precipitation. Coastal Virginia has one of the highest relative sea level rise rates on the Atlantic Coast and the regional planning district commission recommends that Atlas 14 rainfall intensity, duration, and frequency curves be increased by 20% to account for changes in rainfall. The Coastal Community Design Collaborative (CCDC), a partnership between Hampton University Architecture and Old Dominion University Engineering & Technology, has had …

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Pla Polymer Binder In Core Production - Influence On Final Casting Dimensions, Artur Soroczyński, Krzysztof Rechowicz Jan 2025

Pla Polymer Binder In Core Production - Influence On Final Casting Dimensions, Artur Soroczyński, Krzysztof Rechowicz

Virginia Digital Maritime Center (VDMC) Faculty Publications

The foundry industry is seeking an ecological alternative to synthetic molding resins. This study evaluates the technological properties of core sands bonded with biodegradable polylactide (PLA). Cores prepared on a 2% quartz sand matrix were subjected to casting processes using two alloys with extremely different pouring temperatures: gray cast iron (approx. 1200 °C) and AK11 silumin (approx. 710 °C). The research methodology included macroscopic assessment, dimensional analysis using 3D scanning (GOM Inspect), and qualitative knock-out assessment supported by numerical temperature field simulation. The results showed that the high crystallization temperature of cast iron leads to complete thermal degradation of the …

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A Review Of Infrared Thermography Applications For Civil Infrastructure, Prabal Shrestha, Onur Avci, Sahabeddin Rifai, Feras Abla, Michael Seek, Karl Barth, Udaya Halabe Jan 2025

A Review Of Infrared Thermography Applications For Civil Infrastructure, Prabal Shrestha, Onur Avci, Sahabeddin Rifai, Feras Abla, Michael Seek, Karl Barth, Udaya Halabe

Engineering Technology Faculty Publications

Civil infrastructure is continuously subject to aging and deterioration due to multiple factors, which lead to a decline in performance and impact structural health. Accumulated damage on structures increases operational costs and poses significant risks to public safety. Effective maintenance, repair, and rehabilitation strategies are needed to ensure civil infrastructure’s overall safety and reliability. Non-Destructive Evaluation (NDE) methods are utilized to assess latent damage and provide decision-makers with real-time information for mitigating hazards. Within the last decade, there has been a significant increase in the research and development of innovative NDE techniques to improve data processing and promote efficient and …

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Evaluating The Effectiveness Of Stay-In-Place Forms To Improve The Tosional Stability Of Box Beam Bridges During Erection, Karl E. Barth, Michael W. Seek, Gregory K. Michaelson, Dimitra Pyrialakou, Brook T. Woldegabriel Jan 2025

Evaluating The Effectiveness Of Stay-In-Place Forms To Improve The Tosional Stability Of Box Beam Bridges During Erection, Karl E. Barth, Michael W. Seek, Gregory K. Michaelson, Dimitra Pyrialakou, Brook T. Woldegabriel

Engineering Technology Faculty Publications

Cold-formed tub girders provide an effective steel solution for short-span bridges. The girders are often delivered with an open top with stay-in-place forms installed on site. Walkways may be installed to the side of the girder that can induce significant torsion rotations in the open cross section. Full scale tests on girder specimens have shown that installing one or two panels of stay in place forms at the ends of the girder can significantly reduce the torsion rotation of the girder by providing warping resistance. Cantilever tests on the stay in place forms are performed to investigate the influence of …

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