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Full-Text Articles in Engineering

Adsorption Of Per- And Polyfluoroalkyl Substances On Functionalized Minerals: Effects Of Modifier Property And Mineral Structure, Qianqian Dong Aug 2022

Adsorption Of Per- And Polyfluoroalkyl Substances On Functionalized Minerals: Effects Of Modifier Property And Mineral Structure, Qianqian Dong

Theses and Dissertations

ABSTRACTADSORPTION OF PER- AND POLYFLUOROALKYL SUBSTANCES ON FUNCTIONALIZED MINERALS: EFFECTS OF MODIFIER PROPERTY AND MINERAL STRUCTURE

by Qianqian Dong

The University of Wisconsin-Milwaukee, 2022Under the Supervision of Professor Yin Wang

Per-and polyfluoroalkyl substances (PFAS) are a large group of manmade chemicals widely used in various consumer and industrial products. The adverse effect of PFAS exposure includes bioaccumulation, organ damage and birth defects. Although the primary feedstock perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) has been phased out since the 2000s, PFAS are worldwide detectable in water bodies due to the historical production, accumulation and endless substitution of long-chain PFAS in …


Oxidized Graphitic Nano-Amendment Of Cement Composites: Exploring Truly Low Concentrations And Novel Particle Morphologies, Shohana Iffat Jul 2022

Oxidized Graphitic Nano-Amendment Of Cement Composites: Exploring Truly Low Concentrations And Novel Particle Morphologies, Shohana Iffat

Theses and Dissertations

Oxidized graphitic nanoparticles such as multiwalled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs), can produce enhancements in physicomechanical properties of cement composites that are relevant to structural and durability performance, provided that said nanoparticles are well dispersed in the composite. Lower-bound MWCNT concentrations are reported in the literature in the range 0.01-0.05% in weight of cement (wt%). Such concentrations may not be costeffective for practical applications and may also be excessive since they would result in a nanoparticle surface area at or above 105 m2 for 1 m3 of cement paste, or 104.5 m2 for 1 m 3 of concrete, …


Changes In Drought Characteristics Under Future Climate Projections, Diogo Stalin De Alcantara Araujo Jul 2022

Changes In Drought Characteristics Under Future Climate Projections, Diogo Stalin De Alcantara Araujo

Theses and Dissertations

Accumulating evidence on the impact of climate change on droughts, highlight the necessity for developing effective adaptation and mitigation strategies. Global Drought Layers were developed for historic and future runs of nine global climate models (GCM) of the Coupled Model Intercomparison Model 6th phase (CMIP6). Relative changes of drought characteristics were estimated, and hotspots were identified, especially in South America, Africa, Europe, Western USA, and Australia. Further, changes in future drought risk and severity in Australia are quantified. Historic conditions (1981-2014) and projections for mid-century (2015-2050) and end-century (2051-2100) from four shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) are …


Development Of Software Tools For Efficient And Sustainable Process Development And Improvement, Jake P. Stengel Jun 2022

Development Of Software Tools For Efficient And Sustainable Process Development And Improvement, Jake P. Stengel

Theses and Dissertations

Infrastructure is a key component in the well-being of our society that leads to its growth, development, and productive operations. A well-built infrastructure allows the community to be more competitive and promotes economic advancement. In 2021, the ASCE (American Society of Civil Engineers) ranked the American infrastructure as substandard, with an overall grade of C-. The overall ranking suffers when key infrastructure categories are not maintained according to the needs of the population. Therefore, there is a need to consider alternative methods to improve our infrastructure and make it more sustainable to enhance the overall grade. One of the challenges …


Laboratory Assessement Of Emulsion-Cement Paste And Cold Recycled Mixtures At Varying Amounts Of Emulsion, Cement, And Water, Ahmed Saidi Jun 2022

Laboratory Assessement Of Emulsion-Cement Paste And Cold Recycled Mixtures At Varying Amounts Of Emulsion, Cement, And Water, Ahmed Saidi

Theses and Dissertations

The main objective of this study was to assess the performance of cold recycled mixtures (CRMs) at: (1) binder level through evaluating the rheological and mechanical properties of emulsion-cement paste (ECP), and (2) mix level through characterizing the density and performance of CRMs. The testing program for ECPs included multiple stress creep recovery (MSCR), bending beam rheometer (BBR), linear amplitude sweep (LAS), penetration test, and isothermal calorimetry. For CRMs, a balanced mix design (BMD) approach was used to develop performance interaction charts to select optimum contents of emulsion, cement, and water maximizing the resistance of CRMs to rutting and cracking. …


Legal Characterization Of The Challenges Faced By The Construction Industry During Covid-19 And Devaluation Of The Egyptian Pound, Riham Abuzaid Jun 2022

Legal Characterization Of The Challenges Faced By The Construction Industry During Covid-19 And Devaluation Of The Egyptian Pound, Riham Abuzaid

Theses and Dissertations

With all the challenges this past decade has inflicted on the economy on a global scale, Egypt had its share with two major events, starting with the Egyptian pound devaluation against the U.S dollar in 2016 and currently the emergence of the COVID-19 pandemic. These major events instigated the interference of the legal/contractual sectors in the construction market to find solutions that range from agreeable to stringent to protect the assets of their beneficiaries.

Both events are impactful and require extensive analysis to determine and classify each situation. This thesis addresses the implementation of standard internationally acknowledged legislative acts used …


A Model For The Sustainable Achievement Of The Optimum Return For Crops In Greenhouses, Eman Elnahas May 2022

A Model For The Sustainable Achievement Of The Optimum Return For Crops In Greenhouses, Eman Elnahas

Theses and Dissertations

This study provides a tool for accurate estimation of the irrigation water needs for various crop combinations under different environmental conditions; and employs a genetic optimization algorithm to reach optimum combinations. In the interest of sustainability, the source of energy required to drive the pumps is selected to be a renewable source, namely solar energy, which is converted to electricity employing photovoltaic (PV) modules. Having a single crop will lead to an uneconomical system because the PV installed capacity will not be exploited most of the time.

This research was conducted by establishing the required database, generating different scenarios, assessing …


Mechanical Property Relationships Of Cement Or Lime Stabilized Soils Throughout A Pavement's Life, Leigh E.W. Ayers May 2022

Mechanical Property Relationships Of Cement Or Lime Stabilized Soils Throughout A Pavement's Life, Leigh E.W. Ayers

Theses and Dissertations

Soil-cement is an integral part of pavement design, especially in areas that are aggregate deprived, such as Mississippi. Current designs are reliant on the relationship of unconfined compressive strength (UCS) to other mechanical properties. The other properties discussed in this dissertation are Modulus of Elasticity (E), Indirect Tensile Strength (St), and Modulus of Rupture (MOR). This dissertation includes a comprehensive review of past design methods and mechanical property relationships. While some mechanical property relationships were shown to be well understood (i.e. St to UCS), others were not as accurate, especially for the later life mechanical properties (i.e. MOR to UCS …


Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju May 2022

Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju

Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis …


Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates May 2022

Development And Evaluation Of Seasonal, Continental-Scale Streamflow Forecasts, Elissa Marie Yeates

Theses and Dissertations

Methods of forecasting streamflow using atmospheric ensembles and hydrologic routing have greatly improved over the past decades. These forecasts anticipate the timing and magnitude of streamflow peaks, enabling early warning of floods. Recent advances in atmospheric modeling have enabled production of forecasts months ahead, which are less precise but give a useful sense of trends.

The purpose of this study is to produce and evaluate a seasonal streamflow forecast model using a Muskingum routing hydrologic model coupled with runoff from a land surface model, and atmospheric input from a medium-term atmospheric and precipitation model. To evaluate the skill of the …


Enhancing The Performance Of Dowel Type Fasteners And A Case Study Of Timber Truss Failure, Lon A. Yeary May 2022

Enhancing The Performance Of Dowel Type Fasteners And A Case Study Of Timber Truss Failure, Lon A. Yeary

Theses and Dissertations

This document will outline the findings of three separate and independent studies: Study 1: In or around 1972, an experimental building was constructed. One of the intents of the construction project was to demonstrate advancements in wood building construction design. It was value-engineered throughout. That is, its materials and systems were intended to function at or near design capacity. In 2019, part of the roof of the structure collapsed. This case study investigates two potential factors that led to the failure: stress concentration in excess of the 12 allowable stress for 2 × 4 web members and insufficient plywood sheathing …


Environmental Impact And Life Cycle Assessment Of Biomass Supported Power Systems For Rural Communities, Hariteja Nandimandalam May 2022

Environmental Impact And Life Cycle Assessment Of Biomass Supported Power Systems For Rural Communities, Hariteja Nandimandalam

Theses and Dissertations

Dependence on fossil fuels in the electric sector is one of the major contributors towards Greenhouse gas (GHG) emissions. The increase in renewable contribution has been observed in recent years but there is still potential to utilize wood waste in rural communities for electricity generation promoting energy independence and sustainable development. For this study, a life cycle assessment approach was utilized to estimate the emissions of electricity produced from wood residue in a rural community. Therefore, the process from planting to supply for bioenergy facility to generate electricity are included. The results showed a decrease of 92-96 % in global …


Urban Water Quality Monitoring And Analysis Using Event Detection System And Machine Learning Methods, Nabila Nafsin May 2022

Urban Water Quality Monitoring And Analysis Using Event Detection System And Machine Learning Methods, Nabila Nafsin

Theses and Dissertations

Water quality is defined as the measure of physical, chemical, and biological characteristics of water. Monitoring water quality is a growing challenge because of accidental or intentional spills of industrial, domestic, and agricultural wastes into surface water. Conventional methods used for measuring water quality parameters are time-consuming and expensive, making real-time contamination detection difficult. Advanced monitoring technology can be employed for real-time monitoring, providing a reliable and cost-effective solution to water management. CANARY event detection system (EDS) has been used in water distribution networks and wastewater treatment plants for detecting anomalous water quality events and proved to be an effective …


Forecasting Salinity In The Laguna Madre Using Deep Learning, Martin J. Flores Jr. May 2022

Forecasting Salinity In The Laguna Madre Using Deep Learning, Martin J. Flores Jr.

Theses and Dissertations

Salinity is an important metric in the Laguna Madre for establishing the long term health of the local ecological population. By utilizing Deep Learning (DL) techniques, the predicted and forecasted salinity in the Laguna Madre is generated from data provided by the Moderate Resolution Imaging Spectroradiometer (MODIS)-Aqua satellite.

Currently, only one other DL model has been used to forecast Sea Surface Salinity (SSS), being a Recurrent Neural Network (RNN). However, the RNN model requires the prediction of a full area of salinity to function.

As such, several model architectures were tested, with the best one, being a Multi-input MPNN, utilized …


Water Quality Monitoring To Assess Pollutant Loadings In Brownsville Ship Channel Watershed, Ivan Rene Santos Chavez May 2022

Water Quality Monitoring To Assess Pollutant Loadings In Brownsville Ship Channel Watershed, Ivan Rene Santos Chavez

Theses and Dissertations

The Brownsville Ship Channel (BSC) was listed as an impaired waterway from 2010 to 2018 due to screening levels of bacteria concentration. This study aims to address water quality at the three main tributary ditches draining into Brownsville Ship Channel to model present along with future pollutant loads within Brownsville Ship Channel Watershed. Load Duration Curves (LDCs) and Spatial Explicit Load Enrichment Calculation Tool (SELECT) models were developed to determine if current pollutant loads meet water quality standards stablished by the Texas Commission on Environmental Quality (TCEQ), and to estimate average daily potential E. Coli loading contribution from sub-watersheds within …


Detailing Of Carbon Fiber Reinforced Polymer Anchorage For Shear Strengthening, Paul Joseph Ryan May 2022

Detailing Of Carbon Fiber Reinforced Polymer Anchorage For Shear Strengthening, Paul Joseph Ryan

Theses and Dissertations

Carbon Fiber Reinforced Polymers (CFRP) have increased in popularity in the repair and strengthening of reduced shear capacity of concrete bridges. Significant design challenges arise when using CFRP to repair or strengthen bridge girders as the top faces of girders are in contact with decking (i.e. the members cannot be fully wrapped). A full wrap laminates all faces with CFRP and ensures that the failure mode is governed by shear fracture combined with, or followed by, fracture of the CFRP. The Florida Department of Transportation (FDOT) Structural Design Manual permits three-sided wrapping schemes (i.e. U-wraps), but the CFRP must be …


Quantifying Responsiveness In The Vaccine Industry To Evaluate And Improve Pandemic Response, Connor Hill May 2022

Quantifying Responsiveness In The Vaccine Industry To Evaluate And Improve Pandemic Response, Connor Hill

Theses and Dissertations

In the wake of the pandemic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) we can look at many aspects of the global response, including social, scientific, and governmental. Current research in the areas of vaccine development and manufacturing find the process of developing a new vaccine takes an especially long time and is unresponsive. Understanding the factors that influence responsiveness can help organizations be better prepared to address the needs of society should another pandemic strike. Responsiveness can be linked to product, process, and volume. The vaccine development and manufacturing process historically takes years to reach distribution for public use. …


Machine Learning Based Surrogate Model For Hurricane Storm Surge Forecasting In The Laguna Madre, Cesar E. Davila Hernandez May 2022

Machine Learning Based Surrogate Model For Hurricane Storm Surge Forecasting In The Laguna Madre, Cesar E. Davila Hernandez

Theses and Dissertations

Texas coastal communities are at constant risk of hurricane impacts every storm season. It is especially important to model and predict storm surge variations during hurricane and storm events. Traditionally, hurricane storm surge predictions have been the result of numerical hydrodynamics based simulations. This type of simulations often requires high amounts of computational resources and complex ocean modelling efforts. Recently, machine learning techniques are being explored and are gaining popularity in hydrologic and ocean engineering modelling fields based on their performance to model nonlinear relationships and low computational requirements for prediction. Advances in machine learning and artificial intelligence (A.I.) demand …


Behavior Of Narrow Mechanically Stabilized Earth Walls With Secondary Reinforcement, Abraham Alejandro Alvarez Reyna May 2022

Behavior Of Narrow Mechanically Stabilized Earth Walls With Secondary Reinforcement, Abraham Alejandro Alvarez Reyna

Theses and Dissertations

Mechanically Stabilized Earth (MSE) walls have been used in past decades as an alternative, cost-effective, and performance solution to replace conventional retaining walls. AASHTO guidelines recommend a reinforcement length-to-height ratio of 0.7. However, this ratio is not applicable where there exist constraint conditions. FHWA guidelines recommend the minimum reinforcement length-to-height ratio of 0.3 for Narrow Mechanically Stabilized Earth (NMSE) walls in these cases. However, published guidelines have not sufficiently accounted for several parameters influencing NMSE performance and efficiency. Using finite element analysis (PLAXIS 2D), this study focuses on finding a relation between the length-to-height ratio and other parameters/components of the …


Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna May 2022

Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna

Theses and Dissertations

During a high intensity storm events, a series of catastrophic events occur. These catastrophic events include flooding and destruction of infrastructure. Engineers have determined a method to design for high intensity storms based off hydrologic analysis of previous storms. With this data engineers can determine the outflow of major rivers and streams that may impact infrastructure. By determining the watershed engineers can predict the flow of the water and as well as the location of the outfall. In the Rio Grande Valley, water quality is very important because after rain events stormwater from cities is carried out towards the Laguna …


Sars-Cov-2 Rna Persistence In Municipal Wastewater Treatment Systems Proves Wastewater Surveillance Is An Effective Tool For Monitoring Covid-19 Community Health Burdens, Melissa K. Schussman May 2022

Sars-Cov-2 Rna Persistence In Municipal Wastewater Treatment Systems Proves Wastewater Surveillance Is An Effective Tool For Monitoring Covid-19 Community Health Burdens, Melissa K. Schussman

Theses and Dissertations

Wastewater surveillance of SARS-CoV-2 is used worldwide to track COVID-19 infection trends. However, there is no standard method for SARS-CoV-2 measurement from wastewater, and uncertainties of pre-analytical influences from the wastewater collection system persist. This study builds upon the growing body of knowledge surrounding wastewater surveillance and aims to understand how wastewater measurements relate to other public health metrics, explain the influence of wastewater conveyance systems, and improve SARS-CoV-2 detection and quantification from wastewater. Our laboratory has been part of the ongoing Wisconsin SARS-CoV-2 wastewater surveillance program since August 2020, analyzing almost 4,000 samples to date. Through various experiments, our …


Classification Of Acoustic Emission Data Into Load Steps Using An Artificial Neural Network, Allen Ross Apr 2022

Classification Of Acoustic Emission Data Into Load Steps Using An Artificial Neural Network, Allen Ross

Theses and Dissertations

The average age of bridges in South Carolina is approaching 40 years, very close to the 50-year service life. Almost 11% of the bridges in South Carolina are rated as structurally deficient, greater than the national average of 7.5% (South 2021). Health monitoring is the concept that in-situ sensors can continuously monitor civil structures and send real time signals of damage. This process allows for automation and could save time and money on the inspection and load rating of bridges. Health monitoring requires sensors that provide uninterrupted data without sacrificing the functionality of the bridge. A prime candidate for this …


The Effect Of Concrete Material Properties On Rigid Pavement Design In South Carolina, Nicolet Anne Devine Apr 2022

The Effect Of Concrete Material Properties On Rigid Pavement Design In South Carolina, Nicolet Anne Devine

Theses and Dissertations

This thesis presents the effect of concrete material inputs on rigid pavement design in the state of South Carolina. The impact of concrete strength input parameters in the historical AASHTO pavement design method and MEPDG method is investigated using three newly constructed concrete sections, I-85 in Cherokee County, I-20 in Lexington County, and I-85 in Spartanburg County. Strength data obtained from the sections were the result of QA/QC testing provided by the SCDOT during construction, as well as from UofSC laboratory testing. The compressive strength data from these tests was correlated to the elastic modulus and modulus of rupture (which …


Coalitional Game Theory For Stormwater Management And Green Infrastructure Practices, Carly Lawyer Apr 2022

Coalitional Game Theory For Stormwater Management And Green Infrastructure Practices, Carly Lawyer

Theses and Dissertations

As global warming and climate Variability bring about more frequent and intense rainstorms and accelerate sea level rise, our social and built environments are at heightened risk of flood induced damages and consequent costs. This is particularly true for coastal areas, facing the coupled effects of these threats while serving as home to people, businesses, unique landscapes, and historic landmarks. Complex decisions at all levels of government and community planning stand to benefit from increased understanding of possible outcomes and pathways resulting from decentralized human behavior and decision making in the realm of water resources engineering and management. Game theory …


Upper Regime Bedform Geometries And Types As A Function Of Sediment Supply And Grain Size, Sydney Sanders Apr 2022

Upper Regime Bedform Geometries And Types As A Function Of Sediment Supply And Grain Size, Sydney Sanders

Theses and Dissertations

Most research on fluvial bedforms focuses on the study of dunes (lower regime), and much less is known on upper regime bedforms. Studying upper regime bedforms, the conditions in which they form and how the geometry changes with flow and sediment properties is necessary for interpreting the stratigraphic record, estimate flow resistance and reconstruct flow characteristics from observed geometries. Here I present results of laboratory experiments designed to investigate the role of suspended bed material and sediment grain size on upper regime bedforms. Experiments were performed in open channel flow mode in a sediment-feed flume with a 0.19 m wide, …


Investigating The Relationship Of Preventive And Corrective Maintenance In Chiller Assets Using Linear Regression Analysis, Jacob A. Franke Mar 2022

Investigating The Relationship Of Preventive And Corrective Maintenance In Chiller Assets Using Linear Regression Analysis, Jacob A. Franke

Theses and Dissertations

Asset managers must balance maintenance plans between preventive (PM) and corrective maintenance (CM). While PM plans have been a staple for decades, the benefits achieved have not been thoroughly examined at the asset specific level. This study focuses on the U.S. Air Force chiller portfolio to better understand the relationship between PM and CM, utilizing multiple stages of linear regression modeling and data from 14 US Air Force installations. PM and CM were found to be positively correlated, with PM accounting for relatively small portions of the variance experienced in CM. This study reveals the value of standardized data collection …


A Scientometric Analysis Of Smart Sensors In Facility Management And Applications In Air Force Operations, Joseph-Thomas H. Lehotsky Mar 2022

A Scientometric Analysis Of Smart Sensors In Facility Management And Applications In Air Force Operations, Joseph-Thomas H. Lehotsky

Theses and Dissertations

To investigate the areas which smart sensors can be implemented to assist facility managers to optimize limited resources, this research consists of a scientometric analysis to identify the areas of research quantitatively and qualitatively. Existing literature related to smart sensors in facility management operations were compiled and trends were analyzed to determine the ways in which researchers have been applying this technology. The title, abstracts, and keyword were used to perform frequency, networking, and clustering analysis. This research effort serves to provide ways in which Air Force installations can implement smart sensors in a way which fulfills the initiatives posed …


A United States Air Force Site Selection Methodology In A Contested Agile Combat Employment Environment, Zachary T. Moer Mar 2022

A United States Air Force Site Selection Methodology In A Contested Agile Combat Employment Environment, Zachary T. Moer

Theses and Dissertations

The United States Air Force’s (USAF) Agile Combat Employment (ACE) strategy relies on host country access and underlying local infrastructure to facilitate airpower. However, numerous factors, including peer-to-peer threats, complex geopolitics, and intricate supply chain management, often complicate site access and thwart site selection decisions. When shaping the battlespace for future conflict, strategists and planners face the difficult task of identifying optimal locations to conduct adaptive basing operations given these complicating factors. Multi-Criteria Decision Analysis (MCDA) can help strategists appropriately account for competing objectives and maintain a competitive advantage with theater adversaries. This thesis presents an MCDA model that evaluates …


Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes Mar 2022

Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes

Theses and Dissertations

Review of construction-related AM literature is used to identify the advantages, challenges, and current trends of the research. Using a scientometric analysis of 522 bibliographic records, this research systematically analyzed construction related AM research to determine the key research areas and trends. Results showed that starting in 2015, the field has been growing at an exponential rate. Recent AM research focused on materials and reinforcement topics, which matched the most notable challenges of AM, which are material rheology, reinforcement, and lacking construction standards. This study provides an insight into AM research and identifies areas requiring more innovation before its commercial …


A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia Mar 2022

A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia

Theses and Dissertations

The purpose of this research is to explore the utility and current state of touchless technologies. Five categories of technologies are identified as a result of collecting and reviewing literature: facial/biometric recognition, gesture recognition, touchless sensing, personal devices, and voice recognition. A thematic analysis was conducted to evaluate the advantages and disadvantages of the five categories. A reference analysis was also conducted to determine the similarities between articles in each category. Touchless sensing showed to have the most advantages and least similar references. Gesture recognition was the opposite. Comparing analyses shows more reliable technology types are more beneficial and diverse.