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Full-Text Articles in Engineering

Assessing The Feasibility And Mechanism Of Destructive Removal Of Per- And Polyfluoroalkyl Substances (Pfas) From Water, Kaushik Vinaykumar Londhe Dec 2023

Assessing The Feasibility And Mechanism Of Destructive Removal Of Per- And Polyfluoroalkyl Substances (Pfas) From Water, Kaushik Vinaykumar Londhe

Dissertations

One of the most pertinent challenges faced by the drinking water community is the widespread contamination of per- and polyfluoroalkyl substances (PFAS). These anthropogenic chemicals have been ubiquitously used in everyday products such as carpets, stain repellents, dyes, shampoos, non-stick cookware as well as in aqueous firefighting foams. PFAS are linked with adverse health effects in humans such as thyroid disease, obesity, immunological and reproductive disorders and linked to cancer in adults and low birth weight and developmental defects in infants.

Conventional water treatment technologies have proven to be largely ineffective in PFAS remediation, due to their extreme stability and …


Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar Nov 2023

Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar

Dissertations

Water shortage in many coastal parts of the world is reaching alarming situation, including the United Arab Emirates. Urbanization and rapid population growth are generating critical water demands with an increase in per capita consumption. Seawater is usually treated by membrane processes such as Reverse Osmosis (RO). However, this technology is energy intensive and generates excessive brine as a waste. The solution to this problem can be found in natural remediation techniques that can reduce salt concentration from seawater, such as halophytes. A salt-tolerant species can consume Na+ and Cl- ions and increase cellular growth which is termed …


Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq Nov 2023

Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq

Dissertations

Recycling construction waste material offers a sustainable solution to the problem of disposing of concrete construction and demolition waste. The use of basalt fibers (BF) and basalt fiber-reinforced polymer (BFRP) reinforcing bars in concrete structures made of recycled concrete aggregate (RCA) would prolong their service life and reduce the maintenance cost. This research aims to investigate the potential use of BF, RCA, and BFRP reinforcing bars to produce sustainable and steel-free structural concrete. The study consisted of material characterization testing, numerical simulation, and large-scale beam testing.
Material characterization tests were performed on normal-strength concrete (NSC) and high-strength concrete (HSC). The …


Colloidal Behavior Of Nanobubbles And Their Application In Enhancing Plant Growth: Mechanisms Of Nanobubble Interactions With Microbial And Soil Species, Shan Xue Aug 2023

Colloidal Behavior Of Nanobubbles And Their Application In Enhancing Plant Growth: Mechanisms Of Nanobubble Interactions With Microbial And Soil Species, Shan Xue

Dissertations

Climate change has resulted in increasing uncertainties of water resources and disturbance on agricultural activities. For example, the shortage of water resources, land erosion and pollution from runoff significantly affect agricultural sustainability. This dissertation research focuses on the fundamental studies of nanobubble (NB) water and explores the benefits for irrigation to enhance plant germination and growth. Unlike bulk bubbles, NBs exhibit prolonged stability in water and possess large surface areas that facilitate efficient mass transfer and potential tailored reactions (e.g., disinfection). However, the enhancement mechanisms for NBs on seed germination and plant growth remain elusive.

This research first evaluated the …


Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma Dec 2022

Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma

Dissertations

Facet engineering of nanomaterials, especially metals and metal oxides has become an important strategy for tuning catalytic properties and functions from heterogeneous catalysis to electrochemical catalysis, photocatalysis, biomedicine, fuel cells, and gas sensors. The catalytic properties are highly related to the surface electronic structures, surface electron transport characteristics, and active center structures of catalysts, which can be tailored by surface facet control. The aim of this doctoral dissertation research is to study the facet-dependent properties of metal or metal oxide nanoparticles using multiple advanced characterization techniques. Specifically, the novel atomic force microscope-scanning electrochemical microscope (AFM-SECM) and density functional theory (DFT) …


Bioremediation Of Petroleum Hydrocarbons In Coastal Sediments, Charbel Abou Khalil Dec 2022

Bioremediation Of Petroleum Hydrocarbons In Coastal Sediments, Charbel Abou Khalil

Dissertations

The biodegradation of dispersed crude oil in the ocean is relatively rapid (a half-life of a few weeks). However, it is often much slower on shorelines, usually attributed to low moisture content, nutrient limitation, and higher oil concentrations in beaches than in dispersed plumes. Another factor may be the increased salinity of the upper intertidal and supratidal zones since these parts of the beach are potentially subject to prolonged evaporation and only intermittent inundation. Therefore, two laboratory experiments are conducted to investigate whether such an increase in porewater salinity results in additional inhibitory effects on oil biodegradation in seashores.

In …


Developing Distributed Real-Time Hybrid Simulation For Dynamic Response Evaluation Of Floating Wind Turbine, Hezha Lutfalla Sadraddin Dec 2022

Developing Distributed Real-Time Hybrid Simulation For Dynamic Response Evaluation Of Floating Wind Turbine, Hezha Lutfalla Sadraddin

Dissertations

Floating wind turbine (FWT) has a significant role in producing clean and sustainable energy in unlimited spaces with more steady wind and less cost. The design, construction, and safe operation of FWTs require a deep understanding of their dynamic responses under combined aerodynamic and hydrodynamic loads. Conventional FWT model experiments utilize wave tanks and wind tunnels. However, laboratory size and capacity and the scaling conflicts between the Froude and the Reynold numbers in these coupled wind-wave loading tests impose challenges to replicate dynamic responses of FWT. Alternatively, real-time hybrid simulation (RTHS), which combines numerical simulation and physical experiment of FWT …


A Comprehensive Evaluation Of Satellite-Based Precipitation Products And Their Performance In Arid And Temperate Climates, Mohammed Tarig Mahmoud Nov 2022

A Comprehensive Evaluation Of Satellite-Based Precipitation Products And Their Performance In Arid And Temperate Climates, Mohammed Tarig Mahmoud

Dissertations

Accurate and continuous precipitation monitoring is critical to enable effective water resources management; the challenge arises from the spatial and temporal variability of precipitation. The recently launched Global Precipitation Measurement (GPM) satellite has the capability to detect and measure all types of precipitation using advanced instruments. Being at its early stages of development, the products of the GPM IMERG (early, late, and final-run-products) need to be validated using multiple spatial and temporal assessment techniques. Several studies have emerged over the past few years evaluating GPM IMERG results over areas of limited size. These areas were set by hydrologic interest (e.g., …


Behavior Of Novel Cementitious Composites For Use In Sustainable Construction And Rehabilitation, Noah A. Thibodeaux Aug 2022

Behavior Of Novel Cementitious Composites For Use In Sustainable Construction And Rehabilitation, Noah A. Thibodeaux

Dissertations

Cementitious composites are a class of cement-based materials that incorporate a cement paste and other constituents to form a composite material. Cementitious composites may include coarse and/or fine aggregate, admixtures, supplementary cementitious materials (SCMs), or fibers in order to achieve a desired workability, strength, or durability property.

Recently, material scientists and engineers have developed a variety of novel cementitious composites for the purpose of new construction, rehabilitation, and reconstruction applications. Such materials can be used to improve the sustainability of civil infrastructure through the use of recycled, repurposed, or low-embodied carbon materials. Since many of the qualification standards and tests …


Optimizing Speed Profiles For Sustainable Train Operation With Wayside Energy Storage Systems, Leon A. Allen May 2022

Optimizing Speed Profiles For Sustainable Train Operation With Wayside Energy Storage Systems, Leon A. Allen

Dissertations

Large hauling capability and low rolling resistance has put rail transit at the forefront of mass transportation mode sustainability in terms of congestion mitigation and energy conservation. As such, rail vehicles are one of the least energy-intensive modes of transportation and least environmentally polluting. Despite, these positives, improper driving habits and wastage of the braking energy through dissipation in braking resistors result in unnecessary consumption, extra costs to the operator and increased atmospheric greenhouse gas emissions.

This study presents an intelligent method for the optimization of the number and locations of wayside energy storage system (WESS) units that maximize the …


Planning Methodology For Alternative Intersection Design And Selection, Liran Chen May 2022

Planning Methodology For Alternative Intersection Design And Selection, Liran Chen

Dissertations

The recent publication of the 6th Edition of the Highway Capacity Manual included a chapter on Ramp Terminals and Alternative Intersections that introduces various alternative intersection designs and assesses the performance of Median U-turn, Restricted crossing U-turn and Displaced left-turn intersections. Missing from the literature is an alternative intersection selection tool for identifying whether an alternative intersection would be successful under local conditions. With limited information of organized alternative intersection research, most planners must rely heavily on their personal judgement while selecting the most suitable intersection designs. As appealing as alternative intersections are, there is no comprehensive methodology for planners …


A Self-Learning Intersection Control System For Connected And Automated Vehicles, Ardeshir Mirbakhsh May 2022

A Self-Learning Intersection Control System For Connected And Automated Vehicles, Ardeshir Mirbakhsh

Dissertations

This study proposes a Decentralized Sparse Coordination Learning System (DSCLS) based on Deep Reinforcement Learning (DRL) to control intersections under the Connected and Automated Vehicles (CAVs) environment. In this approach, roadway sections are divided into small areas; vehicles try to reserve their desired area ahead of time, based on having a common desired area with other CAVs; the vehicles would be in an independent or coordinated state. Individual CAVs are set accountable for decision-making at each step in both coordinated and independent states. In the training process, CAVs learn to minimize the overall delay at the intersection. Due to the …


Understanding The Interfacial Processes Of Reactive Nanobubbles Toward Agricultural Applications, Xiaonan Shi May 2022

Understanding The Interfacial Processes Of Reactive Nanobubbles Toward Agricultural Applications, Xiaonan Shi

Dissertations

There is a growing interest in nanobubble (NB) technology because of its diverse applications (e.g., detergent-free cleaning, water aeration, ultra-sound imaging and intracellular drug delivery, and mineral processing). NBs have a higher efficiency of mass transfer compared to bulk scale bubbles due to the high specific surface areas. The high specific surface also facilitates physical adsorption and chemical reactions in the gas liquid interface. Furthermore, the collapse of NBs creates shock waves and the formation of hydroxyl radicals (OH).

However, it remains elusive why or how NBs are stabilized in water and particularly, the states of internal pressures of NBs …


The Impact Of Material And Environmental Properties On The Ettringite - Metaettringite Thermochemical Reaction, Aaron Strand May 2022

The Impact Of Material And Environmental Properties On The Ettringite - Metaettringite Thermochemical Reaction, Aaron Strand

Dissertations

The use of energy is an essential need for people, with demand constantly increasing due to an increasing population and an increase in living and comfort standards. Since 1965, world energy consumption has quadrupled. During peak utilization, the strain on the grid infrastructure can be immense. As energy demand fluctuates during different times of the day and year, the energy production needs to scale accordingly This creates inefficiencies within the system such as over building generation capacity or losses from start up or ramping up production. This can be alleviated through load leveling where excess energy generated during low demand …


Reactive Iron Mineral Coatings In Redox Transition Zones Of A Site With Historical Contamination: Abiotic Attenuation, Xin Yin May 2022

Reactive Iron Mineral Coatings In Redox Transition Zones Of A Site With Historical Contamination: Abiotic Attenuation, Xin Yin

Dissertations

Reactive iron mineral coatings are found throughout reduction-oxidation (redox) transition zones and play a significant role in contaminant transformation processes. In this study, an 18.3-meter core is collected, subsampled, and preserved under anoxic conditions to maintain its original redox state. Screening analyses are conducted at sampling increments of 5.08 cm in depth for the following: elemental concentrations with X-ray fluorescence (XRF), sediment pH, sediment oxidation-reduction potential (ORP), total volatile organic carbon (TVOC) in the sample headspace, and abundant bacteria (16S rRNA sequencing). Using the Fe and S gradients correlated with microbial data, five RTZs are delineated. To characterize iron mineral …


Behavior Of Steel Fiber Reinforced Concrete Made With Recycled Concrete Aggregates: Material Characterization And Deep Beam Shear Response, Nancy Kachouh Apr 2022

Behavior Of Steel Fiber Reinforced Concrete Made With Recycled Concrete Aggregates: Material Characterization And Deep Beam Shear Response, Nancy Kachouh

Dissertations

This research aims to examine the performance of concrete made with recycled concrete aggregates (RCAs) and steel fibers. It comprises material characterization tests, large-scale reinforced concrete (RC) deep beam tests, and numerical modeling. Material characterization test parameters included the RCA replacement percentage (30, 70, and 100%) and the steel fiber volume fraction (vf = 1, 2, and 3%). Fourteen large-scale deep beam numerical models with and without web openings made with 100% RCAs and steel fibers were developed and validated through a comparative analysis with test results. A numerical parametric study was conducted to investigate the effect of varying …


Crash Injury Severity Prediction With Artificial Neural Networks, Rima Abisaad Dec 2021

Crash Injury Severity Prediction With Artificial Neural Networks, Rima Abisaad

Dissertations

Motor vehicle crashes are one of our nation's most serious social, economic and health issues. They are the leading cause of death among children and young adults, killing approximately 1.35 million people each year. Providing a safe and efficient transportation system is the primary goal of transportation engineering and planning. To help reduce traffic fatalities and injuries on roadways, crash prediction models are used to forecast the injury severity of potential crashes and apply precautionary countermeasures accordingly. Most of these models are reactive as they use historical crash data to categorize crash-related factors. Recently, advancements have been made in developing …


Connected And Automated Vehicles: Their Implication On Capacity Of A Basic Freeway Section And Impacts On Walkway Safety, Sia Macmillan Lyimo Dec 2021

Connected And Automated Vehicles: Their Implication On Capacity Of A Basic Freeway Section And Impacts On Walkway Safety, Sia Macmillan Lyimo

Dissertations

Autonomous vehicles have recently gained the attention of researchers due to their expected potential benefits on highway traffic streams, such as improving roadway capacity, among others. It is imperative to investigate how these expected benefits can be leveraged in the transportation sector. Understanding the safety and operational benefits helps the concerned transportation agencies and other key stakeholders to make necessary infrastructural and policy adjustments to accommodate such future traffic operation changes. The main goal of this dissertation is to study the impact of connected and automated vehicles on freeway capacity. The simulated environment was created to emulate autonomous vehicle behaviors, …


Impact Of Exposure On Thin Epoxy Overlay Performance, Abul Fazal Mazumder Nov 2021

Impact Of Exposure On Thin Epoxy Overlay Performance, Abul Fazal Mazumder

Dissertations

Thin epoxy overlays are used for improving the condition and extending the service life of bridge decks. The tensile bond pull-off strength, evaluated as per the ASTM C1583, is used as the performance indicator. A failure in the substrate with a tensile strength of 250 psi or greater is considered acceptable. However, the performance evaluated on in-service bridge decks shows inconsistent results. Laboratory studies by several researchers documented a distinct performance difference when the overlays are exposed to room temperatures in comparison to elevated temperatures. However, the most influential parameters such as concrete surface profile, thermal compatibility between overlay and …


Infrastructure Risk Reduction: The Case Of Drinking Water Emergencies, Mark Paine Oct 2021

Infrastructure Risk Reduction: The Case Of Drinking Water Emergencies, Mark Paine

Dissertations

Public water systems are an integral part of community infrastructure. Drinking water contamination or service disruptions have the potential to cause economic losses, limit fire suppression capability, and result in human illnesses. Until 2016, the United States federal government had not issued a disaster declaration due to contaminated water. The first federal drinking water disaster declaration due to contaminated water serves as a sentinel event demonstrating the need to increase focus on public water systems during all phases of emergency management: mitigation, preparation, response, and recovery. Previous studies evaluating risks to vulnerable populations associated with drinking water primarily utilized qualitative …


Short-Term Crash Risk Prediction Considering Proactive, Reactive, And Driver Behavior Factors, Sina Darban Khales Aug 2021

Short-Term Crash Risk Prediction Considering Proactive, Reactive, And Driver Behavior Factors, Sina Darban Khales

Dissertations

Providing a safe and efficient transportation system is the primary goal of transportation engineering and planning. Highway crashes are among the most significant challenges to achieving this goal. They result in significant societal toll reflected in numerous fatalities, personal injuries, property damage, and traffic congestion. To that end, much attention has been given to predictive models of crash occurrence and severity. Most of these models are reactive: they use the data about crashes that have occurred in the past to identify the significant crash factors, crash hot-spots and crash-prone roadway locations, analyze and select the most effective countermeasures for reducing …


Shale Softening Based On Pore Network And Laboratory Investigations, Di Zhang Aug 2021

Shale Softening Based On Pore Network And Laboratory Investigations, Di Zhang

Dissertations

This dissertation consists of two major parts: Firstly, experimental investigation of four major shale softening mechanisms and quantifications of structural parameters. Secondly, numerical simulations of nano-scale flow behaviors using the previous experiments determined parameters based on modified pore network modeling.

Hydraulic fracturing is widely applied to economical gas production from shale reservoirs. Still, the gradual swelling of the clay micro/nano-pores due to retained fluid from hydraulic fracturing causes a gradual reduction of gas production. Four different gas-bearing shale samples are investigated to quantify the expected shale swelling due to hydraulic fracturing. These shale samples are subject to heated deionized (DI) …


Analysis Of Container Throughput: Demand Forecast And Seaport Competitiveness Assessment, Hussain Talat Sulaimani Aug 2021

Analysis Of Container Throughput: Demand Forecast And Seaport Competitiveness Assessment, Hussain Talat Sulaimani

Dissertations

Seaports play a crucial role in the container industry, where they act as important nodes in the transport chain to facilitate international trade. In a competitive market, port capacity plays a significant role in defining its competitive position to attract demand and avoid congestion. Failing to provide suitable capacity results in the loss of market share. Therefore, port decision-makers face the challenge of maintaining and developing suitable port facilities to provide efficient services to port users. One of the aspects that decision-makers consider in the planning and development process is analyzing container demand. The analysis of container demand can be …


Performance Evaluation Of Transportation Systems For Sustainability And Smart-Growth Of Cities: An Integrated Assessment Of Health Impacts, Ahmad Feizi Aug 2021

Performance Evaluation Of Transportation Systems For Sustainability And Smart-Growth Of Cities: An Integrated Assessment Of Health Impacts, Ahmad Feizi

Dissertations

The performance of transportation systems is a significant component that influences the quality of life. The performance evaluation refers to a process of determining how well transportation systems perform regarding their intended goals and objectives. The advancement of information and communication technology and the integration between transportation systems and advanced technologies have directed more attention to the concept of smart cities. Smart cities are constituted of several interrelated components. Therefore, this offers comprehensive and integrated frameworks to evaluate the transportation performance and understanding of multifaceted interactions between the components from a transportation engineering perspective in four sections.

In the first …


Data Mining Of Unstructured Textual Information In Transportation Safety Domain: Exploring Methods, Opportunities And Limitations, Keneth Morgan Kwayu Jun 2021

Data Mining Of Unstructured Textual Information In Transportation Safety Domain: Exploring Methods, Opportunities And Limitations, Keneth Morgan Kwayu

Dissertations

The unprecedented increase in volume and influx of structured and unstructured data has overwhelmed conventional data management system capabilities in organizing, analyzing, and procuring useful information in a timely fashion. Structured data sources have a pre-defined pattern that makes data preprocessing and information retrieval tasks relatively easy for the current technologies that have been designed to handle structured and repeatable data. Unlike structured data, unstructured data usually exists in an unorganized format that offers no or little insight unless indexed and stored in an organized fashion. The inherent format of unstructured data exacerbates difficulties in data preprocessing and information extraction. …


Safe Yield Comparisons For The 1960’S And 2000’S Drought In The Passaic River Basin, Stephanie R. Santos May 2021

Safe Yield Comparisons For The 1960’S And 2000’S Drought In The Passaic River Basin, Stephanie R. Santos

Dissertations

The Passaic River Basin is a complex system of rivers, tributaries, reservoirs, and some of the largest water purveyors in the State of New Jersey. Located in the northeastern part of the State, it drains approximately 800 square miles of water that is used for distribution to the five major purveyors: North Jersey District Water Supply Commission, Passaic Valley Water Commission, Jersey City, Newark, and New Jersey American Water. These purveyors operate under a safe yield, which is defined by the New Jersey Department of Environmental Protection (NJDEP) as the amount of water that should be continuously available should the …


Optimizing Work Zone Schedules Considering Traffic Diversion With Artificial Bee Colony Algorithm, Celina Semaan May 2021

Optimizing Work Zone Schedules Considering Traffic Diversion With Artificial Bee Colony Algorithm, Celina Semaan

Dissertations

Highway maintenance activities often decrease roadway capacity and intrude traffic movements. The need to finish the project on time and under a specific budget while minimizing the traffic congestion and complying with the emission standards requires an appropriate work zone schedule optimization. The objective of this research is to improve the efficiency of work zone activities and minimize the total project cost including maintenance, user, and emission cost.

While previous studies investigated the work zone optimization problem, they did not consider the implementation of emission standards nor applied a green diversion strategy. This dissertation analyzes the optimization of work zone …


A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek Dec 2020

A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek

Dissertations

The introduction of deep learning and big data analytics may significantly elevate the performance of traffic speed prediction. Work zones become one of the most critical factors causing congestion impact, which reduces the mobility as well as traffic safety. A comprehensive literature review on existing work zone delay prediction models (i.e., parametric, simulation and non-parametric models) is conducted in this research. The research shows the limitations of each model. Moreover, most previous modeling approaches did not consider user delay for connected freeways when predicting traffic speed under work zone conditions. This research proposes Deep Artificial Neural Network (Deep ANN) and …


High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv Dec 2020

High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv

Dissertations

This study uses a complex network model to analyze the causes of accidents in high-speed railway operations. By identifying the key factors that led to high-speed railway accidents, hidden safety hazards were discovered. This will help improve the operational safety of the U.S. high-speed rail line under construction.

The analysis uses the regional high-speed railway network in Guangzhou, China as a case study, including the railway (including high-speed railway) accidents that occurred in the company's jurisdiction from 2013 to 2017. With comparative analysis between general railways and high-speed railways, the changes of high-speed railway safety factors are explored. Data analysis …


Characterizing Reactive Iron Mineral Coatings And Their Roles In Natural Attenuation At A Site With Historical Contamination, Han Hua Dec 2020

Characterizing Reactive Iron Mineral Coatings And Their Roles In Natural Attenuation At A Site With Historical Contamination, Han Hua

Dissertations

Reactive iron mineral coatings in redox transition zones play an important role in contaminant attenuation. These mineral coatings include poorly crystalline to crystalline iron sulfides, carbonates, and oxyhydroxides, and are a signature of the biogeochemical processes occurring. To better understand these processes, reactive iron mineral coatings are characterized in an 18-m Anaerobic Core collected from a contaminated industrial site. This study targets redox transition zones uncovered in the core. A suite of complementary analyses is applied to distinguish the surface coating mineralogy using X-ray Diffraction, X-ray fluorescence, and field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray analyzer (EDX). In …