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Full-Text Articles in Engineering

Immobilized Algae For Produced Water Treatment And Desalination, Shibin Nadersha, Ashraf Aly Hassan Dec 2022

Immobilized Algae For Produced Water Treatment And Desalination, Shibin Nadersha, Ashraf Aly Hassan

Department of Civil and Environmental Engineering: Faculty Publications

Produced water (PW) is the effluent generated during oil mining and extraction. On average, for every barrel of oil, 4-5 barrels of PW are generated worldwide. The presence of various contaminants in PW makes it toxic. Disposal of untreated PW into oceans and water bodies can cause adverse effects on human health and the environment. Taking into account the large volumes of it being generated, and its effects on the environment, proper treatment is required before reuse or disposal. Microalgal treatment is an effective method for the bioremediation and biodesalination of produced water when acclimatized algal biomass is used for …


G-Dam: A Distributed Data Storage With Blockchain Framework For Management Of Groundwater Quality Data, Sukrutha L. T. Vangipuram, Saraju P. Mohanty, Elias Kougianos, Chittaranjan Ray Nov 2022

G-Dam: A Distributed Data Storage With Blockchain Framework For Management Of Groundwater Quality Data, Sukrutha L. T. Vangipuram, Saraju P. Mohanty, Elias Kougianos, Chittaranjan Ray

Department of Civil and Environmental Engineering: Faculty Publications

Groundwater overuse in different domains will eventually lead to global freshwater scarcity. To meet the anticipated demands, many governments worldwide are employing innovative and traditional techniques for forecasting groundwater availability by conducting research and studies. One challenging step for this type of study is collecting groundwater data from different sites and securely sending it to the nearby edges without exposure to hacking and data tampering. In the current paper, we send raw data formats from the Internet of Things to the Distributed Data Storage (DDS) and Blockchain (BC) edges. We use a distributed and decentralized architecture to store the statistics, …


Agrostring: Visibility And Provenance Through A Private Blockchain Platform For Agricultural Dispense Towards Consumers, Sukrutha L. T. Vangipuram, Saraju P. Mohanty, Elias Kougianos, Chittaranjan Ray Oct 2022

Agrostring: Visibility And Provenance Through A Private Blockchain Platform For Agricultural Dispense Towards Consumers, Sukrutha L. T. Vangipuram, Saraju P. Mohanty, Elias Kougianos, Chittaranjan Ray

Department of Civil and Environmental Engineering: Faculty Publications

It is a known fact that large quantities of farm and meat products rot and are wasted if correct actions are not taken, which may lead to serious health issues if consumed. There is no proper system for tracking and communicating the status of the goods to their respective stakeholders in a secure way. Consumers have every right to know the quality of the products they consume. Using monitoring tools, such as the Internet of Agricultural Things (IoAT), and modern data protection techniques for storing and sharing, will help mitigate data integrity issues during the transmission of sensor records, increasing …


Hybrid Timber Concrete Composite Slab For Analysis Of Lag Screw Embedment Connections, Jawad Al Lawati, Ece Erdogmus, Dennis Young, Husam Al Dughaishi, Moad Alosta, Zainab Al-Khafaji, Zaher Mundher Yaseen, Abdalrhman Milad Oct 2022

Hybrid Timber Concrete Composite Slab For Analysis Of Lag Screw Embedment Connections, Jawad Al Lawati, Ece Erdogmus, Dennis Young, Husam Al Dughaishi, Moad Alosta, Zainab Al-Khafaji, Zaher Mundher Yaseen, Abdalrhman Milad

Department of Civil and Environmental Engineering: Faculty Publications

Push-out-shear tests were used in this study to analyze lag screw connections in timber-concrete composite (TCC) slabs based on the embedment depth. The goal of this research is to look into the relationship between shear capacity and embedment depth in TCC, as well as to investigate the embedment strength of the wood. Experiments were carried out at different embedment depths (5.08 cm, 7.0 cm, and 8.9 cm). The prepared samples were examined in order to determine the failure modes and provide an accurate assessment of the influence of embedment depth on TCC slabs. The investigation on the embedment strength of …


Effects Of Nutrient Level And Growth Rate On The Conjugation Process That Transfers Mobile Antibiotic Resistance Genes In Continuous Cultures, Mohammadreza Shafieifini, Yuepeng Sun, Zachery R. Staley, University Of Nebraska-Lincoln, Jean-Jack Riethoven, Xu Li Sep 2022

Effects Of Nutrient Level And Growth Rate On The Conjugation Process That Transfers Mobile Antibiotic Resistance Genes In Continuous Cultures, Mohammadreza Shafieifini, Yuepeng Sun, Zachery R. Staley, University Of Nebraska-Lincoln, Jean-Jack Riethoven, Xu Li

Department of Civil and Environmental Engineering: Faculty Publications

Bacteria in the effluent of wastewater treatment plants (WWTPs) can transfer antibiotic resistance genes (ARGs) to the bacteria in receiving water through conjugation; however, there is a lack of quantitative assessment of this phenomenon in continuous cultures. Our objective was to determine the effects of background nutrient levels in river water column and growth rates of bacteria on the conjugation frequency of ARGs from effluent bacteria to river bacteria, as well as on the resulting resistance level (i.e., MICs) of the river bacteria. Chemostats were employed to simulate the discharge points of WWTPs into rivers, where effluent bacteria (donor cells) …


Laboratory Study Of Consolidation Of Marine Soft Soil Using Flocculation-Vacuum Preloading-Electro-Osmosis, Lei Zhang, Yan-Dong Lu, Bing-Hui Wang, Dan-Dan Jin, Ming-Xing Zhu, Chen Fang Sep 2022

Laboratory Study Of Consolidation Of Marine Soft Soil Using Flocculation-Vacuum Preloading-Electro-Osmosis, Lei Zhang, Yan-Dong Lu, Bing-Hui Wang, Dan-Dan Jin, Ming-Xing Zhu, Chen Fang

Department of Civil and Environmental Engineering: Faculty Publications

To solve the technical issues in vacuum preloading method, including the sediment clogging of drains and the limitation of drainage conditions, this study investigated vacuum preloading combined with flocculation and electro-osmosis consolidation for marine soft soil. A series of column settling tests was conducted to determine the optimal organic flocculant for the combined method. With the selected organic flocculant, laboratory tests were performed on the soil samples using the combined consolidation method, in which the electro-osmosis was added at different time moments. The tests considered three representative cases at different time moments: (i) at 48 h, i.e., the initial stage …


Project-Based Learning Promotes Students’Perceived Relevance In An Engineering Statistics Course: A Comparison Of Learning In Synchronous And Online Learning Environments, Wen Huang, Jeremi S. London, Loga A. Perry Sep 2022

Project-Based Learning Promotes Students’Perceived Relevance In An Engineering Statistics Course: A Comparison Of Learning In Synchronous And Online Learning Environments, Wen Huang, Jeremi S. London, Loga A. Perry

Department of Civil and Environmental Engineering: Faculty Publications

Understanding statistics is essential for engineers. However, statistics courses remain challenging for many students, as they find them rigid, abstract, and demanding. Prior research has indicated that using project based learning (PjBL) to demonstrate the relevance of statistics to students can have a significant effect on learning in these courses. Consequently, this study sought to explore the impact of a PjBL intervention on student perceptions of the relevance of engineering and statistics. The purpose of the intervention was to help students understand the connection between statistics and their academic majors, lives, and future careers. Four mini-projects connecting statistics to students’ …


Dataset For Large-Scale, Lateral-Torsional Buckling Tests Of Continuous Beams In A Grillage System, Ahmed Rageh, C. Shawn Sun, Daniel G. Linzell, Jay A. Puckett Aug 2022

Dataset For Large-Scale, Lateral-Torsional Buckling Tests Of Continuous Beams In A Grillage System, Ahmed Rageh, C. Shawn Sun, Daniel G. Linzell, Jay A. Puckett

Department of Civil and Environmental Engineering: Faculty Publications

A number of large-scale tests of a grillage system are summarized and reduced data are provided. The tests were completed in association with a Louisiana Transportation Research Center (LTRC) project for the Louisiana Department of Transportation and Development (LA DOTD) whose goal was to better quantify behavior and limit states of steel bridge floor systems to refine longitudinal member (stringer) load- rating calculations. A number of tests focused on the behavior of the stringers resting on transverse members (a floorbeam), a system akin to a grillage. The system was proportioned with the expectation that stringer lateral-torsional buckling, a key steel …


Study And Comparison Of The Performance Of Steel Frames With Brb And Sma Bracing, Mohsen Jalalvandi, Ahmad Soraghi, Seyed Mohammadreza Farooghi Mehr, Abbas Haghollahi, Ali Abasi Aug 2022

Study And Comparison Of The Performance Of Steel Frames With Brb And Sma Bracing, Mohsen Jalalvandi, Ahmad Soraghi, Seyed Mohammadreza Farooghi Mehr, Abbas Haghollahi, Ali Abasi

Department of Civil and Environmental Engineering: Faculty Publications

Designing steel structures with Concentric Braced Frame (CBF) lateral systems has been common in recent decades. This type of bracing has a quite unstable and complicated behavior in relatively intense earthquakes. This study tries to improve the seismic behavior of steel frames with CBF braces equipped with Shape Memory Alloy (SMA) and Buckling Restrained Braces (BRBs). In this manner, a multi-story building with inverted V chevron bracing was considered. Nonlinear time-history analyses have been performed using OpenSEES software. The dynamic responses of frames with SMA and BRB braces were compared. The results showed that the SMA and BRB braces provide …


Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu Jul 2022

Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu

Department of Civil and Environmental Engineering: Faculty Publications

Coda wave interferometry (CWI) has been used to measure the relative wave-velocity change (dV/V) caused by small changes in materials. This study uses the stretching processing technique which has been used for CWI analysis to investigate velocity changes of direct longitudinal (P) wave, direct shear (S) wave, and coda wave in concrete by choosing different time windows of ultrasonic signals. It is found that the obtained wave-velocity change depends on the time window position, because the relative contribution of P wave and S wave is different in each signal window. This paper presents three experimental scenarios of velocity …


Chemical Toxicants In Water: A Geohealth Perspective In The Context Of Climate Change, Naveen Joseph, Tate Libunao, Elizabeth Herrmann, Shannon L. Bartelt-Hunt, Catherine R. Propper, Jesse E. Bell, Alan S. Kolok Jul 2022

Chemical Toxicants In Water: A Geohealth Perspective In The Context Of Climate Change, Naveen Joseph, Tate Libunao, Elizabeth Herrmann, Shannon L. Bartelt-Hunt, Catherine R. Propper, Jesse E. Bell, Alan S. Kolok

Department of Civil and Environmental Engineering: Faculty Publications

The editorial focuses on four major themes contextualized in a virtual GeoHealth workshop that occurred from June 14 to 16, 2021. Topics in that workshop included drinking water and chronic chemical exposure, environmental injustice, public health and drinking water policy, and the fate, transport, and human impact of aqueous contaminants in the context of climate change. The intent of the workshop was to further define the field of GeoHealth. This workshop emphasized on chemical toxicants that drive human health. The major calls for action emerged from the workshop include enhancing community engagement, advocating for equity and justice, and training …


Revealing Driver Psychophysiological Response To Emergency Braking In Distracted Driving Based On Field Experiments, Ying Li, Li Zhao, Kun Gao, Yisheng An, Jelena Andric Jul 2022

Revealing Driver Psychophysiological Response To Emergency Braking In Distracted Driving Based On Field Experiments, Ying Li, Li Zhao, Kun Gao, Yisheng An, Jelena Andric

Department of Civil and Environmental Engineering: Faculty Publications

Purpose – The purpose of this paper is to characterize distracted driving by quantifying the response time and response intensity to an emergency stop using the driver’s physiological states.

Design/methodology/approach – Field tests with 17 participants were conducted in the connected and automated vehicle test field. All participants were required to prioritize their primary driving tasks while a secondary nondriving task was asked to be executed. Demographic data, vehicle trajectory data and various physiological data were recorded through a biosignalsplux signal data acquisition toolkit, such as electrocardiograph for heart rate, electromyography for muscle strength, electrodermal activity for skin conductance and …


Metal-Free Synthesis Of N-Heterocycles Via Intramolecular Electrochemical C-H Aminations, Huiqiao Wang, Yongjun Zheng, Hucheng Xu, Jiaru Zou, Congrui Grace Jin Jun 2022

Metal-Free Synthesis Of N-Heterocycles Via Intramolecular Electrochemical C-H Aminations, Huiqiao Wang, Yongjun Zheng, Hucheng Xu, Jiaru Zou, Congrui Grace Jin

Department of Civil and Environmental Engineering: Faculty Publications

N-heterocycles are key structural units in many drugs, biologically interesting molecules and functional materials. To avoid the residues of metal catalysts, the construction of N-heterocycles under metal-free conditions has attracted much research attention in academia and industry. Among them, the intramolecular electrochemical C-H aminations arguably constitute environmentally friendly methodologies for the metal-free construction of N-heterocycles, mainly due to the direct use of clean electricity as the redox agents. With the recent renaissance of organic electrosynthesis, the intramolecular electrochemical C-H aminations have undergone much progress in recent years. In this article, we would like to summarize the advances in this research …


Assessing The Effectiveness Of Problem-Based Learning Across Two Concrete Construction Courses, Anthony Torres, Jiong Hu, Vedaraman Sriraman, Araceli Martínez-Ortiz, Jorge Membrillo-Hernández May 2022

Assessing The Effectiveness Of Problem-Based Learning Across Two Concrete Construction Courses, Anthony Torres, Jiong Hu, Vedaraman Sriraman, Araceli Martínez-Ortiz, Jorge Membrillo-Hernández

Department of Civil and Environmental Engineering: Faculty Publications

The goal of this study is to assess the effectiveness of a Problem-Based Learning (PBL) pedagogy that was implemented in two different concrete construction courses. Both courses are a part of an industry focused four-year undergraduate concrete degree program. One of the classes focused on concrete problems, diagnosis, and repair of existing concrete, while the other class focused on handling and management methods of various concrete mixtures. In both courses, a PBL pedagogy was implemented such that students were self-learning and discovering the knowledge through an action-research case study. The action-research case study was specific to the course outcomes relevant …


Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu Jan 2022

Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu

Department of Civil and Environmental Engineering: Faculty Publications

Coda wave interferometry (CWI) has been used to measure the relative wave-velocity change (dV/V) caused by small changes in materials. This study uses the stretching processing technique which has been used for CWI analysis to investigate velocity changes of direct longitudinal (P) wave, direct shear (S) wave, and coda wave in concrete by choosing different time windows of ultrasonic signals. It is found that the obtained wave-velocity change depends on the time window position, because the relative contribution of P wave and S wave is different in each signal window. This paper presents three experimental scenarios of velocity …


Geospatial Distribution Of Age-Adjusted Incidence Of The Three Major Types Of Pediatric Cancers And Waterborne Agrichemicals In Nebraska, Balkissa S. Ouattara, Jagadeesh Puvvula, Azar Abadi, Siddhi Munde, Alan S. Kolok, Shannon Bartelt-Hunt, Jesse E. Bell, Christopher S. Wichman, Eleanor Rogan Jan 2022

Geospatial Distribution Of Age-Adjusted Incidence Of The Three Major Types Of Pediatric Cancers And Waterborne Agrichemicals In Nebraska, Balkissa S. Ouattara, Jagadeesh Puvvula, Azar Abadi, Siddhi Munde, Alan S. Kolok, Shannon Bartelt-Hunt, Jesse E. Bell, Christopher S. Wichman, Eleanor Rogan

Department of Civil and Environmental Engineering: Faculty Publications

This study was conducted to examine, at the county level, the relationship between pediatric cancer incidence rate and atrazine and nitrate mean concentrations in surface and groundwater. A negative binomial regression analysis was performed to investigate the association between central nervous system (CNS) tumors, leukemia, lymphoma, and atrazine and nitrate mean concentrations in groundwater. The age-adjusted brain and other CNS cancer incidence was higher than the national average in 63% of the Nebraska counties. After controlling for the counties socio-economic status and nitrate concentrations in groundwater, counties with groundwater atrazine concentrations above 0.0002 μg/L had a higher incidence rate for …


Probability-Based Crack Width Estimation Model For Flexural Members Of Underground Rc Box Culverts, Sang-Hyo Kim, Syed Haider Ali Shah, Sang-Kyun Woo, Inyeop Chu, Chungwook Sim Jan 2022

Probability-Based Crack Width Estimation Model For Flexural Members Of Underground Rc Box Culverts, Sang-Hyo Kim, Syed Haider Ali Shah, Sang-Kyun Woo, Inyeop Chu, Chungwook Sim

Department of Civil and Environmental Engineering: Faculty Publications

Crack control for slabs and beams in current design practices in Korea are based on the Frosch’s model, which is adapted in ACI 318. It is more difficult to have consistent quality control in underground construction sites, such as the RC box culverts used for electric power distribution built below the ground level. There are more discrepancies between the as-built dimensions and the design dimensions provided in drawings in these structures. Due to this variability in construction error, the crack widths measured in such structures have higher potential to have more differences than the calculated values. Although crack control is …


Assessing The Impacts Of Covid-19 On Activity-Travel Scheduling: A Survey In The Greater Toronto Area, Alireza Dianat, Jason Hawkins, Khandker Nurul Habib Jan 2022

Assessing The Impacts Of Covid-19 On Activity-Travel Scheduling: A Survey In The Greater Toronto Area, Alireza Dianat, Jason Hawkins, Khandker Nurul Habib

Department of Civil and Environmental Engineering: Faculty Publications

The COVID-19 lockdown provided many individuals an opportunity to explore changes in their daily routines, particularly when considered in combination with an ever-changing Information and Communication Technology (ICT) landscape. These new routines and alternative activities have the potential to be continued in the post-COVID era. Transportation planners must understand how routines vary to effectively estimate activity-travel scheduling. The purpose of this study is to determine the influence of the COVID-19 pandemic lockdown on activity-travel behavior and the adoption of ICT-based alternative options. A special emphasis is placed on predicting the long-term effects of this disturbance on activity-travel scheduling. This study …


Effects Of Friction On The Dynamic Behavior Of Flexible Rocking Bodies, S. Mohammadreza Farooghi Mehr, Christine E. Wittich Jan 2022

Effects Of Friction On The Dynamic Behavior Of Flexible Rocking Bodies, S. Mohammadreza Farooghi Mehr, Christine E. Wittich

Department of Civil and Environmental Engineering: Faculty Publications

Flexible rocking bodies are freestanding structures that are free to deform and rock, potentially overturning, when subject to ground excitation. Prior research on the seismic behavior of this type of structure typically assumed sufficient friction at the ground surface to avoid sliding motion. However, experimental observations showed that this assumption was often violated and structures demonstrated non-negligible sliding during their responses. The overarching goal of this study is to evaluate the impact of sliding on the overturning response of flexible rocking bodies. To this end, a two-dimensional analytical model was developed in a Lagrangian formulation, which is presented in this …