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Articles 1741 - 1770 of 39790
Full-Text Articles in Civil and Environmental Engineering
Preliminary Assessment Of Non-Volatile Particulate Matter And Gaseous Emissions From A Premixed Pre-Vaporized Combustor Designed For Civil Supersonic Transport, Ugochukwu Ewuzie, Godwin Ifeanyi Ogbuehi, Steven Achterberg, Monday Uchenna Okoronkwo, Philip D. Whitefield
Preliminary Assessment Of Non-Volatile Particulate Matter And Gaseous Emissions From A Premixed Pre-Vaporized Combustor Designed For Civil Supersonic Transport, Ugochukwu Ewuzie, Godwin Ifeanyi Ogbuehi, Steven Achterberg, Monday Uchenna Okoronkwo, Philip D. Whitefield
Miners Solving for Tomorrow Research Conference
No abstract provided.
Innovative Design Methodology For Durable Open-Graded Friction Course Asphalt Mixtures, Anas Abualia
Innovative Design Methodology For Durable Open-Graded Friction Course Asphalt Mixtures, Anas Abualia
LSU Doctoral Dissertations
Open-graded friction course (OGFC) is a thin asphalt mixture surface layer with a high percentage of coarse aggregates and high interconnected air voids, which provides improved skid resistance, visibility, and decreased pavement-tire noise. However, construction personnel at DOTD reported that conventional OGFC mixtures have short service life (raveling distress). Further, their structural contribution to the pavement structure is commonly neglected and designed only for functionality purposes.
The objective of this study was to develop a rational mix design methodology to improve the durability of OGFC asphalt mixtures. Specific objectives are to: (1) conduct a rheological and chemical characterization of polymer-, …
Arbuscular Mycorrhizal Fungi Combined With Biosolids And Biochar Sustained Phytostabilization And Enhanced Soil Properties Of Mine Tailings, Emma Kettler, Mariam K. Al-Lami, Joel Gerard Burken
Arbuscular Mycorrhizal Fungi Combined With Biosolids And Biochar Sustained Phytostabilization And Enhanced Soil Properties Of Mine Tailings, Emma Kettler, Mariam K. Al-Lami, Joel Gerard Burken
Miners Solving for Tomorrow Research Conference
No abstract provided.
Integrating Standards For Infrastructure Improvement And Resilience In University Curricula, Lisa Greenwood, Jennifer Schneider, Sumita Mishra, Yewande S. Abraham, Shriram Karpoora Sundara Pandian
Integrating Standards For Infrastructure Improvement And Resilience In University Curricula, Lisa Greenwood, Jennifer Schneider, Sumita Mishra, Yewande S. Abraham, Shriram Karpoora Sundara Pandian
Articles
In today’s ever-changing world, we are increasingly vulnerable to shocks and stresses that disrupt industry and society. Persistent threats from natural and manmade hazards require our communities and infrastructure to be resilient despite possible disruption. Creating robust infrastructures is founded on operational and physical standards to withstand and respond to threats such as environmental exposures, climate change, and informational security breaches. The significant U.S. investment in infrastructure projects through the Infrastructure Investment and Jobs Act has amplified the need for professionals in engineering and related fields who – in addition to technical knowledge - possess the necessary knowledge and skill …
Underlying Mechanisms Of The Effect Of Microfines Of Manufactured Sand On Non-Linear Structural Build-Up Of Cement Paste, Jiang Zhu, Jiaping Liu, Kamal H. Khayat, Xin Cheng, Wei Zhao, Zhen Li, Xin Shu, Yongbo Huang
Underlying Mechanisms Of The Effect Of Microfines Of Manufactured Sand On Non-Linear Structural Build-Up Of Cement Paste, Jiang Zhu, Jiaping Liu, Kamal H. Khayat, Xin Cheng, Wei Zhao, Zhen Li, Xin Shu, Yongbo Huang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The rheological properties of cement-based materials made with manufactured sand vary with the content and physio-chemical properties of microfines in the sand. However, the evaluation of rheological properties regarding the structural build-up at early-age hydration remains challenging for the cementitious materials prepared with different manufactured sands, due to complicated underlying structuration mechanisms. This paper studies the effect of disparate microfines of different manufactured sands on the non-linear growth of static yield stress of cement pastes at rest. The paste mixtures were prepared with 0.40 and 0.275 water-to-cement mass ratio (W/C) and had a fixed mini-slump flow of 240 ± 5 …
Impulse, Spring 2025, Jill Fier, Micayla Standish, Jerome J. Lohr College Of Engineering
Impulse, Spring 2025, Jill Fier, Micayla Standish, Jerome J. Lohr College Of Engineering
Impulse (Jerome J. Lohr College of Engineering Publication)
2 | Faculty, Staff Honored
4 | The State of Lithium
6 | 100 Years of Ag and Biosystems Engineering
8 | Major Milestones
12 | Distinguished Engineer Geldert-Murphy
14 | Distinguished Engineering Heitkamp
16 | By the Numbers
18 | Space Grant Consortium at SDSU
20 | Healthcare Systems Engineering Program
22 | Ridgway Three-Peat
23 | Aerospace Club Launches
24 | Power and Energy Scholarships
25 | More Take Part in Nasa Challenges
26 | Weber Recognized as Student Leader
30 | Wild Hare Racing Ready
32| Sebern’s Success as Sole Operator
34 | Meink: From Prairie to …
Turning Farm Waste Into Energy: Pragmatic Approaches For Cleaner Midwestern American Communities, Rebecca Gaisie
Turning Farm Waste Into Energy: Pragmatic Approaches For Cleaner Midwestern American Communities, Rebecca Gaisie
Selected or Submitted Student Research Papers/Projects
Mismanagement of farm waste in the Midwest of the United States has resulted in significant methane emissions, water contamination, and public health concerns. The present manure management rules are still inconsistent, underfunded, and insufficient to motivate individuals to behave in a way that benefits the environment, despite increasing concerns about the environment. This policy study investigates anaerobic digestion as a potential means to convert waste into energy that could support rural and environmental development. Some of the problems with the federal and state legislation examined in this study under an EPI framework are a lack of incentives, inadequate technical support, …
Co2 Utilization For Cementitious Materials - A Review, Seongho Han, Jae Hong Kim, Rohitashva Kumar Singh, Surendra P. Shah
Co2 Utilization For Cementitious Materials - A Review, Seongho Han, Jae Hong Kim, Rohitashva Kumar Singh, Surendra P. Shah
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
This review examines methods for utilizing CO2 in construction materials to reduce the carbon footprint of cement and concrete production. Key approaches include direct carbonation of calcium silicates through CO2 curing, use of industrial by-products as supplementary cementitious materials activated by carbonation, production of alternative binders and aggregates via CO2 treatment of waste materials, injection of CO2 into fresh concrete mixtures, and use of CO2-dissolved mixing water. Both academic research and emerging commercial technologies are covered. While these methods show promise for enhancing material properties and sequestering CO2, challenges remain in optimizing …
Development Of Sustainable Nano-Engineered Cementitious Composites Reinforced With Graphene Oxide From Invasive Seaweed, Steven Garcia, Will Weber, Noah Chun
Development Of Sustainable Nano-Engineered Cementitious Composites Reinforced With Graphene Oxide From Invasive Seaweed, Steven Garcia, Will Weber, Noah Chun
Civil, Environmental and Sustainable Engineering Senior Theses
This research explores the integration of graphene oxide (GO) derived from invasive sargassum seaweed into cementitious composites to enhance concrete performance while addressing critical environmental and sustainability challenges. With the dual goal of reducing the carbon footprint of cement and repurposing harmful sargassum blooms in Puerto Rico, the research investigates the viability of sargassum-derived GO (SGO) as a partial cement substitute in mortar mixes. The study is motivated by the urgent need to lower cement-related CO₂ emissions—currently contributing nearly 8% of global totals—and by the ecological and economic burdens caused by the accumulation of sargassum along coastlines. Graphene oxide, with …
Bridging Deterministic And Probabilistic Analysis For Dam Safety, Giselle Aviles
Bridging Deterministic And Probabilistic Analysis For Dam Safety, Giselle Aviles
Civil, Environmental and Sustainable Engineering Senior Theses
Dams play a critical role in water supply, flood control, energy generation, and infrastructure resilience. However, many existing dams face significant risks due to aging structures, evolving environmental conditions, and outdated design methodologies. These dams pose a danger to downstream populations, demanding greater attention to investment in measures to help reduce risks to public safety and economic assets. Traditional deterministic methods for dam stability assessments rely on static factors of safety (FS), often resulting in either overly conservative or underestimated designs. In this approach, engineers input known material properties, loads, and the dam's geometry into a single FS, which is …
Cob Structure Optimization For Oaxacan Community Center, Dana Johnson, Benjamin Lanzas, Alfonso Zepeda Perez
Cob Structure Optimization For Oaxacan Community Center, Dana Johnson, Benjamin Lanzas, Alfonso Zepeda Perez
Civil, Environmental and Sustainable Engineering Senior Theses
Oaxaca, Mexico is one of the most seismically active states in the country. Earthen-based structures are common in this area as well due to their cultural acceptance, affordability, and accessibility. However, due to the seismicity, these structures often face challenges related to durability. This project serves as an exploration, aimed at increasing the lifespan and resilience of cob construction. The design builds off of the work of GRUPEDSAC, a nonprofit focused on utilizing bioconstruction to provide structures for rural communities in Mexico. This thesis proposes the incorporation of a hybrid wall system that incorporates cob with timber framing, and is …
Pajaro River Levee Remedial Design For Climate Resiliency, Anna Krebs, Karina Martin, Olivia Leonardis
Pajaro River Levee Remedial Design For Climate Resiliency, Anna Krebs, Karina Martin, Olivia Leonardis
Civil, Environmental and Sustainable Engineering Senior Theses
With climate change causing extreme weather events, low-income, underrepresented residents living in Pajaro, California need a more resilient flood mitigation solution because existing infrastructure– the Pajaro River Levee– has recently failed. A hydraulic analysis and overtopping analysis was performed to evaluate potential levee cross sections for a 1.7 mile stretch along the Pajaro River in California. These cross-sections were assessed based on both their material costs and ability to provide sufficient evacuation time.
Changes In The Western Flank Of The North Atlantic Subtropical High Since 1140 Ce: Extremes, Drivers, And Hydroclimatic Patterns, Joshua C. Bregy, Justin T. Maxwell, Scott M. Robeson, Grant L. Harley, Valerie Trouet
Changes In The Western Flank Of The North Atlantic Subtropical High Since 1140 Ce: Extremes, Drivers, And Hydroclimatic Patterns, Joshua C. Bregy, Justin T. Maxwell, Scott M. Robeson, Grant L. Harley, Valerie Trouet
Publications
Summer circulation and moisture patterns in the Southeast United States are controlled by the position of the North Atlantic subtropical high. In a warming climate, the subtropical high is projected to strengthen and expand west, but there remains uncertainty regarding its variability and linkages to natural drivers. Here, we use a tree-ring network across the Southeast United States to reconstruct the relative intensity of the pressure gradient across the subtropical high’s western flank over the past 870 years. Variations in the flank’s position and the pressure gradient have been a major driver of the hydroclimate—including creating a Southeast-Caribbean moisture dipole—since …
Gis Cpd Geospatial Skills, Niamh O'Reilly
Gis Cpd Geospatial Skills, Niamh O'Reilly
Case studies: Digital Education
The GIS CPD programme is delivered to people from industry wishing to develop their Geospatial skills in GIS. For many this is an important skill. Many organisations and companies encourage and pay for their staff to attend the programme and get the CPD Students gain important skills for managing, analysing and presenting geospatial data in a GIS environment. certificate. Students come from many different industries including local authorities, semi state bodies, National mapping agency, transport consultant practices, cable companies, environmental companies. The programme has been running for almost 30 years by my former colleague Eamonn Donnelly. Up until the pandemic …
Hybrid Treatment Method Of Biofiltration Preceded With Advanced Oxidation Process For The Removal Of Emerging Contaminants From The Wastewater Treatment Plant Effluent, Anjali Mohan Payathuparambil
Hybrid Treatment Method Of Biofiltration Preceded With Advanced Oxidation Process For The Removal Of Emerging Contaminants From The Wastewater Treatment Plant Effluent, Anjali Mohan Payathuparambil
Theses
The global demand for potable quality water has been on a continuous rise. Consequently, water reuse is now considered as an alternative to significantly expand supplies of freshwater in communities facing water shortages. Most of the conventional wastewater treatment plants (WWTP) are not efficient in the removal of emerging contaminants from the water, which will cause serious issues to the environment, human and animal life. This research investigated the possibilities of treating wastewater for reuse. First, the feasibility of utilizing a biofiltration system without pre-treatment for removing emerging contaminants from the WWTP effluent was investigated. Two types of biofilter media- …
Design And Evaluation Of Geopolymer Composite As A Potential Sorbent Of Heavy Metals From Water, Ebtesam Mohammed Alghafri
Design And Evaluation Of Geopolymer Composite As A Potential Sorbent Of Heavy Metals From Water, Ebtesam Mohammed Alghafri
Theses
Reducing the levels of heavy metals in water is crucial, given their severe environmental and health impacts. Various methods exist for heavy metals removal. Yet, they mostly come with multiple drawbacks, such as costly treatments and limited efficiency. Previous studies have found geopolymer to be a promising sorbent because it is synthesized using by-product materials, making it an eco-friendly and economically sustainable alternative. Limited studies explored the sorption potential of fly ash-slag blended geopolymers; none examined the effect of mix design factors synergically on sorption, mechanical properties, and durability, and few considered solution characteristics and operating conditions simultaneously. Therefore, this …
A Bayesian Belief Networks Approach To Prioritize Road Safety Mitigation Measures For Eco-Mobility Modes, Fatmah Mohamed Alyammahi
A Bayesian Belief Networks Approach To Prioritize Road Safety Mitigation Measures For Eco-Mobility Modes, Fatmah Mohamed Alyammahi
Theses
This study presents an innovative decision-making approach that enables the prioritization of road safety measures for eco-mobility users—pedestrians, cyclists and light-electric micromobility riders—in Abu Dhabi. The analysis uses 2032 eco-mobility crash records (1016 pedestrian, 567 bicycle, 449 e-scooter) from 2020-2023 supplied by Abu Dhabi Police and the Department of Municipalities and Transport. A supervised Bayesian Belief Network (BBN) was constructed around six empirically estimated variables: visibility, predictability, road curvature, obstructions, lighting and speed limit. Maximum-likelihood conditional-probability tables were derived from the cleaned dataset; Beta priors were applied only where cell counts were sparse. Ten conventional machine-learning models—including Random Forest, Gradient …
Quality Assurance Framework For Recovered Binders And Aggregates From Asphalt Mixtures Incorporating Recycled Materials, Eslam Deef-Allah, Magdy Abdelrahman
Quality Assurance Framework For Recovered Binders And Aggregates From Asphalt Mixtures Incorporating Recycled Materials, Eslam Deef-Allah, Magdy Abdelrahman
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
This study proposes that a proactive quality assurance (QA) framework for asphalt mixes with recycled materials, i.e., reclaimed asphalt pavement and recycled asphalt shingles, should be developed. Quality control (QC) is generally concerned with the contractor's obligation to produce mixes which meet the job mix formula (JMF) targets. However, QA considers the variability in fabrication processes and materials and offers monitoring by evaluating the contractor's performance. Although both aggregate gradations and asphalt contents were within the JMF specifications, the recovered binders revealed significant differences from the contract binders in the JMF. Rheological tests indicated increased stiffness and elasticity but reduced …
Live Recording Of Lectures, Louise Lynch
Live Recording Of Lectures, Louise Lynch
Case studies: Digital Education
The final year module, consisting of 2-hour lectures and 2-hour tutorials, focuses on worked examples. To support students, especially those repeating the module, lectures were recorded and uploaded to Brightspace. Due to the difficulty of the subject and the small class size, in-person delivery was prioritised. The IT 360 mic was used for audio only, no video was recorded, calculations were done on OneNote Class Notebook using the pen functionality of the Surface Pro. This method gives students immediate access to worked examples. Open Broadcast Studio (OBS) was employed to manage different programmes without screen sharing interruptions, while maintaining the …
Numbas For Formative Assessment, Louise Lynch
Numbas For Formative Assessment, Louise Lynch
Case studies: Digital Education
Numbas is an open-source e-assessment system aimed at mathematics and other numerate disciplines. It allows for the setup of individual assessments for students, increasing academic integrity. Numbas can autograde attempts, and the use of the Learning Tool Interoperability (LTI) within Brightspace allows instructors to view attempts, monitor progress, and alter marks where applicable. This adds a valuable element for both formative and summative assessments. In this module, Numbas was used to provide students with individual parameters for the same problems as part of their continuous assessment. These problems would consist of several steps and typically take over 30 minutes to …
Incorporating Screenpal Video To Brightspace Quiz “Hints” Function, Michael O Connor
Incorporating Screenpal Video To Brightspace Quiz “Hints” Function, Michael O Connor
Case studies: Digital Education
I have used the quiz function in Brightspace for some time as an asynchronous learning support and formative assessment technique for various cohorts from apprentice to UG FT students. Typically, I would create several MCQ quizzes around key learning outcomes (LOs) or “muddiest point” discoveries in the classroom. These quizzes were set up to allow the students unlimited attempts, with results published automatically and all question attempts shown with correct answers. While it was effective and well received (interesting particularly by apprentices whose summative assessment results are often high stakes) I often felt it became a repetitive answer selection exercise …
I-280 Wildlife Culvert, Gunner Craig, Tate Reese
I-280 Wildlife Culvert, Gunner Craig, Tate Reese
Civil, Environmental and Sustainable Engineering Senior Theses
Interstate 280 (I-280) serves as one of two (2) main arteries between San Francisco and the peninsula and south Bay Area. Being situated through various nature reserves at the foothills of the Santa Cruz Mountains, I-280 creates a barrier between said mountains and surrounding areas, disrupting migratory patterns. The heavy usage of this road, along with natural migratory patterns of large and medium sized mammals in the area results in high amounts of wildlife vehicle collisions (WVC’s). In order to provide remedial efforts, the team explored various methods to alleviate WVC’s. Ultimately the final proposed design consisted of a cast …
Ptap Memo: Methods For Tn Reduction Of Sewering, Unh Stormwater Center
Ptap Memo: Methods For Tn Reduction Of Sewering, Unh Stormwater Center
UNH Stormwater Center
No abstract provided.
Investigating The Discrepancies Between Acoustic And Radar Measurements Of Water Level Using Data Analysis And Computational Modeling, Ohiedul Haque Mohammad Asad
Investigating The Discrepancies Between Acoustic And Radar Measurements Of Water Level Using Data Analysis And Computational Modeling, Ohiedul Haque Mohammad Asad
Civil & Environmental Engineering Theses & Dissertations
Observations indicate that there is a discrepancy between water level measurements from NOAA’s acoustic gauges and radar gauges. NOAA’s acoustic gauges use a downward-looking acoustic sensor that measures the instantaneous distance from the sensor to the water level. To create a calm water surface for measurements, the sensor is placed in a PVC tube that penetrates the water surface to a certain depth. This tube is called the stilling well. In this thesis, discrepancies in water level measurements from acoustic and radar sensors were explored through data analysis and computational modeling. Specifically, the correlations between the error, which is defined …
Valorization Of Industrial Wastes To Low-Carbon Minerals, Nandan Nag
Valorization Of Industrial Wastes To Low-Carbon Minerals, Nandan Nag
Civil & Environmental Engineering Theses & Dissertations
This study concentrates on developing methods for utilizing industrial waste materials such as red mud and phosphate slag. In this study, an electrochemical process was developed for recovering iron metal powder from red mud. Red mud is a waste material from aluminum refineries. Although red mud can be utilized as a construction and building material, its use is becoming controversial due to its high metal content, which contributes to its toxicity. However, the high iron oxide content in red mud makes it a good feedstock for producing iron. In this project, we employed an electrochemical technique for extracting iron powder …
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. …
Low Dissolved Oxygen Operation Enhances Biological Phosphorus Removal In Wastewater Treatment, Haley Morgan
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 …
Measurement Of Groundwater And Contaminant Fluxes In Fractures Using A Combined System Of Passive Flux Meter And Multiport Sampler, Qasim Raza Khan
Measurement Of Groundwater And Contaminant Fluxes In Fractures Using A Combined System Of Passive Flux Meter And Multiport Sampler, Qasim Raza Khan
Dissertations
Groundwater and contaminant movement in fractured rock aquifers is highly variable. Its dependence on fracture apertures and orientation as well as fracture network interconnectivity is not well understood. This poses a challenge to the measurement of groundwater and contaminant fluxes, especially when using open-hole techniques, which significantly alter natural flow conditions by connecting different fractures along an open borehole or a well. Hence, downhole techniques to directly measure groundwater fluxes and map fractures' locations, orientations, and apertures are considered valuable tools. In this work, the use of Fractured Rock Passive Flux Meter (FRPFM) with invisible tracer and visible dye component …
Analysis Of Responder-Involved Struck-By Crashes, Jacob Wilhelm
Analysis Of Responder-Involved Struck-By Crashes, Jacob Wilhelm
Doctoral Dissertations and Master's Theses
Emergency responders face significant risks of injury and death from struck-by crashes while operating on or near roadways. Annually, about 50 responders are killed, and hundreds more are injured, leading to operational disruptions and damage to life-saving equipment (ERSI, 2024). This study takes a data-driven approach to identify key risk factors and effective countermeasures for reducing the severity of struck-by crashes. Key findings indicate that struck-by crashes most frequently occur on weekends during late-night hours (2 AM–4 AM), often at crash scenes or disabled vehicle scenes on limited-access highways. Driver behavior – particularly “D” drivers (distracted, drugged, drowsy, disgruntled) – …
Evaluating The Impact Of Access Density On Pedestrian And Bicycle Safety, Charles Hruda
Evaluating The Impact Of Access Density On Pedestrian And Bicycle Safety, Charles Hruda
Doctoral Dissertations and Master's Theses
This study examines the impact of access density on pedestrian and bicycle crash rates in urban areas of Florida. Access management, defined as the strategic control of vehicular access points along roadways, plays a crucial role in mitigating conflicts between various roadway users. Previous research has established a positive correlation between access density and crash rates, yet limited studies have analyzed its effects on vulnerable road users such as pedestrians and cyclists.
To quantify these impacts, this study identified high-crash roadway segments using Florida Department of Transportation (FDOT) data. Geometric, traffic, crash, and access management information was collected and analyzed …