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Full-Text Articles in Environmental Engineering

Ground Tire Rubber As A Sustainable Additive: Transforming Desert Sand Behavior, Nabil Ismael, Dalya Ismael, Asmaa Al-Ahmad Jan 2024

Ground Tire Rubber As A Sustainable Additive: Transforming Desert Sand Behavior, Nabil Ismael, Dalya Ismael, Asmaa Al-Ahmad

Engineering Technology Faculty Publications

Managing waste tires presents a significant challenge globally, particularly in regions experiencing high temperatures and shortage of landfill sites. This issue is affecting countries like Kuwait, where the abundance of waste tires is a major source of environmental and safety risks, particularly during the intensely hot summer months. This extreme heat has sparked numerous fires, leading to substantial air pollution due to thick black smoke. Given the limited disposal options, recycling waste tires and finding practical applications for ground tire rubber (GTR) is essential. To address the challenge, a comprehensive laboratory testing program was conducted, using locally produced rubber aggregates …


Recognizing The Potential To Reduce Ghg Emissions Through Air Transportation Electrification, Julio Roa, Joseph Oldham, Marina Lima Jul 2023

Recognizing The Potential To Reduce Ghg Emissions Through Air Transportation Electrification, Julio Roa, Joseph Oldham, Marina Lima

Mineta Transportation Institute

California is aggressively moving forward with efforts to deploy zero-emission transportation technology to fight climate change, especially the Greenhouse Gas (GHG) emissions from the high-impact transportation sector. However, to date, the investments California has made with Cap-and-Trade funding have focused on ground transportation and some marine sources and not the aircraft at the over 140 airports in the state. Through a California-focused comprehensive GHG emissions analysis, this research project seeks to determine how RAM using electric/hybrid electric aircraft can provide new high-speed transportation for high-priority passenger and cargo movement within Fresno County and connections to coastal urban centers. Using VISION, …


Columbus, Nebraska: Southern Housing Development Design Proposal, Ryan Weyers, Caiden Dynek, Alex Papa, Brexton Robertson, Kaden Perala May 2023

Columbus, Nebraska: Southern Housing Development Design Proposal, Ryan Weyers, Caiden Dynek, Alex Papa, Brexton Robertson, Kaden Perala

Honors Theses

The following paper proposes the design and creation of a new housing development in the city of Columbus, Nebraska in a lot to the south of the city and directly north of the Columbus wastewater treatment plant. The goal of this proposal is to provide readers with confidence that our company is the most qualified to complete the project and will create the safest, most comfortable, most efficient, and most cost-effective final design. This proposal seeks to offer a solution to the lack of affordable housing for the growing workforce in Columbus. In order to arrive at this solution, each …


Virtual Accident Curb Risk Habituation In Workers By Restoring Sensory Responses To Real-World Warning, Namgyun Kim, Laurent Grégoire, Moein Razavi, Niya Yan, Changbum R. Ahn, Brian A. Anderson Jan 2023

Virtual Accident Curb Risk Habituation In Workers By Restoring Sensory Responses To Real-World Warning, Namgyun Kim, Laurent Grégoire, Moein Razavi, Niya Yan, Changbum R. Ahn, Brian A. Anderson

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

In high-risk work environments, workers become habituated to hazards they frequently encounter, subsequently underestimating risk and engaging in unsafe behaviors. This phenomenon has been termed "risk habituation"and identified as a vital root cause of fatalities and injuries at workplaces. Providing an effective intervention that curbs workers' risk habituation is critical in preventing occupa-tional injuries and fatalities. However, there exists no empirically supported intervention for curbing risk habituation. To this end, here we investigated how experiencing an accident in a virtual reality (VR) environment affects workers' risk habituation toward repeatedly exposed workplace hazards. We examined an underlying mechanism of risk habituation …


Data-Driven Analysis For Facility Management In Higher Education Institution, Ashish Kumar Pampana, Jungho Jeon, Soojin Yoon, Theodore J. Weidner, Makarand Hastak Nov 2022

Data-Driven Analysis For Facility Management In Higher Education Institution, Ashish Kumar Pampana, Jungho Jeon, Soojin Yoon, Theodore J. Weidner, Makarand Hastak

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Planned Preventive Maintenance (PPM) and Unplanned Maintenance (UPM) are the most common types of facility maintenance. This paper analyzes current trends and status of Facility Management (FM) practice at higher education institutions by proposing a systematic data-driven methodology using Natural Language Process (NLP) approaches, statistical analysis, risk-profile analysis, and outlier analysis. This study utilizes a descriptive database entitled "Facility Management Unified Classification Database (FMUCD)" to conduct the systematic data-driven analyses. The 5-year data from 2015 to 2019 was collected from eight universities in North America. A preprocessing step included but was not limited to identifying common data attributes, cleaning noisy …


Large Eddy Simulations Of Wind Shear From Passing Vehicles Under A Freeway Overpass, Hamid Rahai, Assma Begum Oct 2022

Large Eddy Simulations Of Wind Shear From Passing Vehicles Under A Freeway Overpass, Hamid Rahai, Assma Begum

Mineta Transportation Institute

California is moving toward a 100% clean energy future, and expanded wind energy will be a major component of the state’s future energy portfolio. Innovations in wind energy resources will move California closer to achieving its goal. To gain a better understanding of transient pressure and the wind shear generated at the bridge poles from passing vehicles, this study performed large-eddy simulations of a vehicle (also called an Ahmed body) moving under a freeway overpass at a distance of 0.75 w (width) from the bridge poles. Results include transient contours of mean velocity, turbulent kinetic energy, vorticity, and pressure around …


North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev Jan 2022

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Theses

The following project report was a study of the North 14th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14th Street and the 14th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …


Cruser Place Green Streets Plan, Neal Friedman Jan 2022

Cruser Place Green Streets Plan, Neal Friedman

Master of Urban and Regional Planning Capstone Projects

Combining green and complete street design techniques leads to multiple environmental, social and economic benefits that often enhance each other's effectiveness. In urban areas confronting increased pressures of sea level rise, green streets, which incorporate landscaped features or vegetative areas to manage stormwater within the right of way, can be crucial pieces of pedestrian oriented urban design and multimodal planning frameworks that consider and plan for diverse, complementary transportation options. This plan works with the Colonial Place and Riverview Civic League as well as the Norfolk Preservation Collective to come up with green street design recommendations in order to strengthen …


Transportation Sustainability, Eleni Christofa Jan 2021

Transportation Sustainability, Eleni Christofa

Sustainability Education Resources

An overview of sustainable transportation planning practices and management strategies and policies; current transportation trends; environmental and energy policies; nonmotorized modes (mainly bicycles and pedestrians); public transportation; life-cycle assessment for transportation infrastructure; alternative fuel vehicles; vehicle emission estimation models; demand management strategies (including parking policies, pricing strategies).


The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay Jan 2021

The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay

Civil & Environmental Engineering Faculty Publications

We combine archival research, semi-analytical models, and numerical simulations to address the following question: how do changes to channel geometry alter tidal properties and flood dynamics in a hyposynchronous, strongly frictional estuary with a landward decay in tidal amplitudes? Records in the Saint Johns River Estuary since the 1890s show that tidal range has doubled in Jacksonville, Florida. Near the estuary inlet, tidal discharge approximately doubled but tidal amplitudes increased only ∼6%. Modeling shows that increased shipping channel depths from ∼5 to ∼13m drove the observed changes, with other factors like channel shortening and width reduction producing comparatively minor effects. …


Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 1. Scamper Method Characterization, Dennis R. Fitz, Kurt Bumiller, Charles Bufalino, David E. James Apr 2020

Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 1. Scamper Method Characterization, Dennis R. Fitz, Kurt Bumiller, Charles Bufalino, David E. James

Civil and Environmental Engineering and Construction Faculty Research

Based on emission factors derived from the AP-42 algorithm, particulate matter from paved roads has been estimated to be a major source of PM10 of geologic origin. This is an empirical formula based on upwind-downwind measurement of PM10 concentrations and is dependent solely on the silt loading of the pavement and the weight of vehicles. A number of upwind-downwind studies conducted in urban areas to validate this algorithm have been generally inconclusive because the PM10 concentration difference between upwind and downwind often is within the measurement uncertainty. In the approach presented here PM10 concentrations were measured directly behind a moving …


A Novel Self-Healing System: Towards A Sustainable Porous Asphalt, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen Mar 2020

A Novel Self-Healing System: Towards A Sustainable Porous Asphalt, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Self-healing asphalt, aimed to produce a sustainable asphalt pavement using green technology, has been studied in the past two decades. Technologies including encapsulated rejuvenator and induction heating have been proposed, demonstrated in the laboratory, and gradually evaluated in field application. This paper looks into the synergy effect of the above two technologies, where induction heating serves as the asphalt damage repair mechanism, requiring just 2 min heating time and encapsulated rejuvenator will replenish (rejuvenate) aged asphalt binder and reinstate bitumen’s healing ability. Moreover, the increased temperature from induction heating could in turn accelerate the diffusion process of rejuvenator into aged …


Finding Patterns In Subsurface Using Bayesian Machine Learning Approach, Wang Hui Mar 2020

Finding Patterns In Subsurface Using Bayesian Machine Learning Approach, Wang Hui

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Stochastic simulation approaches and uncertainty quantification are usually adopted for gaining insight into variability in soil stratigraphy configurations. Previous investigations at geotechnical site characterization and interpretation can be broadly categorized into geostatistics- and process-based methods. On the other hand, modern site exploration techniques provide high-quality, dense datasets in physical spaces with high resolution, either directly from sensors (for example, cone penetration testing data) or indirectly from geophysical inversion (such as seismic inversion, electromagnetic induction inversion, and ground penetrating radar). In this work, anisotropy and heterogeneity are considered as possible patterns that inherently exist in the observations, and these are inferred …


A Smart Growth & Equity Framework And Tool For Measuring, Understanding, And Realizing Transportation Land Use Coordination For Sustainability, Livability, And Equity, Bruce Appleyard, Chris Allen, Jonathan Stanton Feb 2020

A Smart Growth & Equity Framework And Tool For Measuring, Understanding, And Realizing Transportation Land Use Coordination For Sustainability, Livability, And Equity, Bruce Appleyard, Chris Allen, Jonathan Stanton

Mineta Transportation Institute

The coordination and integration of transportation and land use (also known as “smart growth”) has been a long-standing goal for planning and engineering professionals, but to this day remains an elusive concept to realize. As this approach is a widely recognized as key to achieving sustainable, livable, and equitable (SLE) outcomes for individuals and society, a key aim of this report is to instill the coordination of transportation and land use into practice by the collection of key actors and agents (MPOs, DOTs, and local land use authorities, etc.) through new measurement and policy guidance frameworks and tools. A fundamental …


Carbon-Based Interlayers In Perovskite Solar Cells, Aleksandr P. Litvin, Xiaoyu Zhang, Kevin Berwick, Anatoly V. Fedorov, Weitao Zheng, Alexander V. Baranov Jan 2020

Carbon-Based Interlayers In Perovskite Solar Cells, Aleksandr P. Litvin, Xiaoyu Zhang, Kevin Berwick, Anatoly V. Fedorov, Weitao Zheng, Alexander V. Baranov

Articles

Perovskites are solution-processed, high-performance semiconductors of interest in low-cost photovoltaics. The interfaces between the perovskite photoactive layers and the top and bottom contacts are crucial for efficient charge transport and minimizing trapping. Control of the collection of charge carriers at these interfaces is decisive to device performance. Here, we review recent progress in the realization of efficient perovskite solar cells using cheap, easily processed, stable, carbon-based interlayers. Interface materials including graphene, carbon nanotubes, fullerenes, graphene quantum dots and carbon dots are introduced and their influence on device performance is discussed.


Wastewater Treatment Fatty Acids For Biodiesel Production, Zachary Christman Jan 2020

Wastewater Treatment Fatty Acids For Biodiesel Production, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wastewater scum is the thick oily substance that floats on top of the primary and secondary tanks within a wastewater treatment plant. Scum has a 30% to 60% lipid content making it an excellent resource for the biodiesel industry. Also the use of scum would reduce the cost of current management practices such as landfill disposal or incineration. In this article there is an overview of lipid byproducts currently being produced at wastewater treatment plants today. This is followed by a presentation showing a full length process for turning wastewater scum into biodiesel raw material.


Moving From Walkability? Evaluation Traditional And Merging Data Sources For Evaluating Changes In Campus-Generated Greenhouse Gas Emissions, Troy Kawahara, Bo Liu, Anurag Pande, Calvin Thigpen, Carole Turley Voulgaris Nov 2019

Moving From Walkability? Evaluation Traditional And Merging Data Sources For Evaluating Changes In Campus-Generated Greenhouse Gas Emissions, Troy Kawahara, Bo Liu, Anurag Pande, Calvin Thigpen, Carole Turley Voulgaris

Mineta Transportation Institute

Universities are increasingly committing to reduce campus-generated greenhouse gas emissions, whether voluntarily or in response to a legal mandate. As an initial step to keeping these commitments, universities need an accounting of baseline greenhouse gas emissions levels and means of monitoring changes in campus-generated greenhouse gas emissions over time. Commute-generated greenhouse gas emissions from travel to and from campus by students and employees are among the most difficult to quantify. This report examines some of the challenges associated with estimating campus-generated greenhouse gas emissions and evaluates ways to address those challenges. The purpose of this study is to identify changes …


Participatory Sensing-Based Geospatial Localization Of Distant Objects For Disaster Preparedness In Urban Built Environments, Hongjo Kim, Youngjib Ham Nov 2019

Participatory Sensing-Based Geospatial Localization Of Distant Objects For Disaster Preparedness In Urban Built Environments, Hongjo Kim, Youngjib Ham

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Although the benefit of participatory sensing for collecting local data over large areas has long been recognized, it has not been widely used for various applications such as disaster preparation due to a lack of geospatial localization capability with respect to a distant object. In such applications, objects of interest need to be ro- bustly localized and documented for supporting data-driven decision-making in site inspection and resource mobilization. However, participatory sensing is inappropriate to localize a distant object due to the absence of ranging sensors in citizens' mobile devices; thus, the localization accuracy varies to a large extent. To address …


Simulation Of The Impact Of Connected And Automated Vehicles At A Signalized Intersection, Hamad Bader Almobayedh, Deogratias Eustace, Philip Appiah-Kubi Oct 2019

Simulation Of The Impact Of Connected And Automated Vehicles At A Signalized Intersection, Hamad Bader Almobayedh, Deogratias Eustace, Philip Appiah-Kubi

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Intersections are locations with higher likelihood of crash occurences and sources of traffic congestion as they act as bottlenecks compared with other parts of the roadway networks. Consequently, connected and automated vehicles (CAVs) can help to improve the efficiency of the roadways by reducing traffic congestion and traffic delays. Since CAVs are expected to take control from drivers (human control) in making many important decisions, thus they are expected to minimize driver (human) errors in driving tasks. Therefore, CAVs potential benefits of eliminating driver error include an increase in safety (crash reduction), smooth vehicle flow to reduce emissions, and reduce …


Evaluation And Enhancement Of Carbon Sequestration Potential Of Existing Vegetation Along Roadsides, Vikram Kapoor, Jeffrey Hutchinson, Samer Dessouky Aug 2019

Evaluation And Enhancement Of Carbon Sequestration Potential Of Existing Vegetation Along Roadsides, Vikram Kapoor, Jeffrey Hutchinson, Samer Dessouky

Publications

The objectives of this study were to evaluate the vegetative composition and carbon sequestration potential of vegetation along a major roadway in Texas. Soil and vegetation were evaluated along IH-35 within Bexar County for composition and carbon content. Three 20 m transects were placed at each site and percent vegetative cover was estimated and above ground plant biomass, and soil was collected from three 0.25 m2 subplots along each transect. Plant and soil samples were analyzed for carbon content. Two non-native grasses, bermudagrass and King Ranch bluestem, were the dominant cover at all sites accounting for > 90% coverage at several …


Biomethane Production From Distillery Wastewater, Zachary Christman Jun 2019

Biomethane Production From Distillery Wastewater, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Distillery wastewater treatment is a great ecological problem, for example, India produces 2.7 billion liters of alcohol that results in 40 billion liters of wastewater. However, this material can be seen as a resource since 11 million cubic meters of biogas at 60% methane could be produced in addition to cleaning the water. The distillery has two options of what to do with the biogas. The first is to use the biogas to fuel the distillery making the production plant more energy efficient and removing some of the need to buy natural gas. The other is to upgrade the biogas …


Unl-Cc Outdoor Education Center Master Plan, Marie Wagner Apr 2019

Unl-Cc Outdoor Education Center Master Plan, Marie Wagner

Honors Theses

The following report contains the work done by the group Griswold Engineering in completion of the Senior Design requirements for Civil Engineering and the Honors Requirements of the Project Manager. As the project manager, my job was to organize the project as a whole and to work alongside the Structural Engineer on the project. One of the main problems to overcome was the division of labor amongst the group. The project was originally conceived as a group project with one project manager and five other students to serve as the project engineers in each subdiscipline. Since this group only had …


Civil Engineering Design Of Cornhusker Council's Outdoor Education Center, Kelly Weiler Apr 2019

Civil Engineering Design Of Cornhusker Council's Outdoor Education Center, Kelly Weiler

Honors Theses

A team of geotechnical, structural, hydraulic, environmental, and transportation experts collaborated to provide engineering solutions to the Cornhusker Council in an effort to solve the current problems facing their Outdoor Education Center. This results of this project provided the structural design of three bridges on the property, transportation plans for two parking lots and roadway design, geotechnical recommendations for soil testing and erosion prevention, and an environmental and hydraulic analysis of the property. A major challenge in the design of this project is the consideration of the dangers and regulations that accompany the floodway and floodplain regions on site. Various …


Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi Apr 2019

Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Understanding the key factors that contribute to transit travel times and travel time variability is an essential part of transit planning and research. Delay that occurs when buses service bus stops, dwell time, is one of the main sources of travel time variability and has therefore been the subject of ongoing research to identify and quantify its determinants. Previous research has focused on testing new variables using linear regressions that may be added to models to improve predictions. An important assumption of linear regression models used in past research efforts is homoscedasticity or the equal distribution of the residuals across …


Measuring Landscape Performance: Case Study Investigation, Hannah Michelle Lopresto, Brandon Zambrano, Catherine De Almeida Aug 2018

Measuring Landscape Performance: Case Study Investigation, Hannah Michelle Lopresto, Brandon Zambrano, Catherine De Almeida

UCARE Research Products

Participating in the Landscape Architecture Foundation’s 2018 Case Study Investigation has been an incredibly informative experience for our research team at the University of Nebraska-Lincoln. We are eager to shine a spotlight on the landscape performance of two Great Plains projects: P Street Corridor, a revitalized downtown streetscape in Lincoln, Nebraska, and Tom Hanafan River’s Edge Park, a waterfront redevelopment in Council Bluffs, Iowa. Working on the post-occupancy study of both projects has been extremely beneficial in understanding how reclaiming underutilized sites can create high-performing landscapes. Both are public projects in urban settings with primary goals of transforming formerly unpleasant, …


Spot-R By Triax, Purdue Ect Team Jan 2018

Spot-R By Triax, Purdue Ect Team

ECT Fact Sheets

Triax’s Spot-r system was developed to tackle the construction industry’s unique safety and productivity challenges, stemming from a demonstrated lack of total jobsite visibility and automatically collected, easily accessible field data. Spot-r by Triax combines a proprietary mesh network with sensor technology to record and transmit previously unattainable workforce and equipment location, activity and safety data within a defined area – all in real-time.

The Spot-r network is installed around the site and operates in a 900 MHz network, with a subset using a cellular connection to forward Spot-r sensor data to Triax’s custom, cloud dashboard. In the hazardous construction …


Mdp (Machine Drive Power) Intelligent Compaction Technology, Purdue Ect Team Jan 2018

Mdp (Machine Drive Power) Intelligent Compaction Technology, Purdue Ect Team

ECT Fact Sheets

Caterpillar developed MDP (Machine Drive Power) technology to fill this gap. Rather than an accelerometer and vibratory drum, it uses the principle of rolling resistance to provide indications of soil stiffness. This allows it to perform more reliably on cohesive and granular soils with less variability than accelerometer systems. It also means that the technology can be used on both vibratory and static drum compactors, which are often used on larger sites. While the technology is quite useful on its own, it is even better as a complementary technology to the existing accelerometer-based systems. Contractors who use vibratory soil compactors …


Purdue’S Biowall, Purdue Ect Team Jan 2018

Purdue’S Biowall, Purdue Ect Team

ECT Fact Sheets

Mechanical ventilation, energy recovery ventilation, and infiltration (air that leaks into a building) are commonly used to introduce fresh air. These are all valid approaches, but a living plant-based filter is an innovative complement to these traditional technologies. A Biowall has the potential to improve indoor air quality while reducing the quantity of air needed for ventilation, creating the potential for energy savings. Figure 1 shows a Biowall prototype being evaluated in the ReNEWW House, a research home located near the Purdue University campus (http://www.renewwhouse.com/).


Datumate, Purdue Ect Team Oct 2017

Datumate, Purdue Ect Team

ECT Fact Sheets

Datumate is digitally transforming civil engineering processes used in construction, surveying and infrastructure inspection markets with fully automated, highly precise, cost effective and safe tools. It utilizes state-of-the-art image processing and advanced drones and camera technologies dramatically reducing the amount of time surveying crews spend in the field, speeding up construction progress checks and shortening infrastructure inspection duration, while maintaining survey grade accuracy. The intuitive, simple and automated solutions increase productivity by saving field and office time in civil engineering and inspection projects of roads, intersections, stockpile volumes, topography, piping, industrial facilities, bridges, property surveys, building facades, railways, cellular infrastructure …


Drones For Commercial Last-Mile Deliveries: A Discussion Of Logistical, Environmental, And Economic Trade-Offs, Miguel Figliozzi Sep 2017

Drones For Commercial Last-Mile Deliveries: A Discussion Of Logistical, Environmental, And Economic Trade-Offs, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

There are no studies that model the potential effectiveness of Unmanned Aerial Vehicles (UAVs) or drones to reduce CO2e lifecycle (including both utilization and vehicle phase) emissions when compared to conventional diesel vans, electric trucks, electric vans, and tricycles. This study presents a novel analysis of lifecycle UAV and ground commercial vehicles CO2e emissions.