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Full-Text Articles in Engineering

Sea Level Rise Impacts On Wastewater Treatment Plants And Their Social Vulnerability Differences, David S. P. Robinson Mar 2023

Sea Level Rise Impacts On Wastewater Treatment Plants And Their Social Vulnerability Differences, David S. P. Robinson

Theses and Dissertations

Many of the United States’ major cities that have a high population are located along the coast. The number of people residing in low elevation coastal areas, be-low 10 meters, is increasing. Coastal areas may be affected by various short- and long-term climate hazards, such as sea level rise (SLR). Climate change induced SLR will threaten residents and infrastructure in low-lying coastal areas. A household’s capacity to respond to hazards is highly dependent on its socio-demographic situation which determines its social vulnerability. Wastewater treatment facilities area particularly critical piece of infrastructure often located in low-lying areas due to gravity fed …


Temporal And Spatial Variability Of Specific Energy Consumption For Atmospheric Water Generators, Anthony T. Brenes Mar 2023

Temporal And Spatial Variability Of Specific Energy Consumption For Atmospheric Water Generators, Anthony T. Brenes

Theses and Dissertations

Atmospheric Water Generators (AWG) produce potable water from the moisture in the air, providing a potentially viable water source in austere locations or emergency response scenarios. In this study, the operating constraints of three existing commercially available AWG devices are investigated, compared to historical weather data from across the continental United States. Utilizing linear regression modeling and weather station data for the years of 1985-2019, the monthly and spatial trends of energy demand to produce water from these devices are evaluated. Energy and water production efficiencies for the devices are highly dependent on environmental conditions with relative humidity and temperature …


Protection Of Linear Assets In Arctic Regions Using Basic Expeditionary Airfield Resources (Polaar Bear), Christopher P. Lintz Mar 2023

Protection Of Linear Assets In Arctic Regions Using Basic Expeditionary Airfield Resources (Polaar Bear), Christopher P. Lintz

Theses and Dissertations

In the 2018 United States National Defense Strategy, the Department of Defense mandated that forces are to be more dynamic and decentralized. The Arctic region was a key topic that was addressed. This means that in the future, it is possible that personnel will need to operate in the Arctic, away from the standard built up infrastructure, to enhance the capabilities of the Air Force and enable the power projection required for mission execution. When establishing a new location, water systems are one of the first requirements for setting up a temporary base infrastructure. However, the Air Force’s current expeditionary …


Topological Variability In Water Distribution Networks, James M. Anderson Mar 2023

Topological Variability In Water Distribution Networks, James M. Anderson

Theses and Dissertations

Water distribution networks are critical infrastructure characterized by difficulties in their assessment and deteriorating performance due to aging components. Resilience analysis of networked infrastructure has replaced traditional risk analysis to focus on performance. Global Resilience Analysis can provide useful information to decision makers and system managers regarding repair and expansion of networks. Network performance has been found to be directly informed by network structure. This work leverages graph theory to assess network qualities that correlate with resiliency characteristics across 69 real world water networks. These networks are then grouped by their structural properties through k-means clustering and compared using parametric …


Environmental Trade-Offs Of Reverse Osmosis Water Purification Units (Rowpus) And Bottled Water, Caleb A. Boone Mar 2023

Environmental Trade-Offs Of Reverse Osmosis Water Purification Units (Rowpus) And Bottled Water, Caleb A. Boone

Theses and Dissertations

The Department of Defense (DoD) conducts many remote missions around the globe. As part of any remote basing strategy, potable water needs to be secured. Currently, there are three primary means of procuring potable water at remote locations: bottled water, on-site purification, or tie-in to existing, local infrastructure. The purpose of this study is to determine the environmental tradeoffs of bottled water and on-site treatment via a Reverse Osmosis Water Purification Unit (ROWPU), which uses multiple levels of filtration to make potable water from freshwater or saline water. A cradle-to- gate assessment was developed for both systems to create a …


Mission Dependency Weighted Water Distribution Networks, Payten A. Connally Mar 2023

Mission Dependency Weighted Water Distribution Networks, Payten A. Connally

Theses and Dissertations

How does the United States Air Force (USAF) assess and plan to replace their most critical drinking water infrastructure? The historical answer is to wait for it to break and then replace or repair the failed pipe. While this has been the process in the past, it is no longer a sustainable approach with resources and funding becoming more constrained in the public and private sectors, and aging assets approaching the end of their usable life. The USAF has taken the first step in asset management to identify their underground water lines, but they have not developed ways to convey …


The Kinetics Of Biocontaminant Inactivation: A Comparative Study With Bacillus Globigii And Bacillus Anthracis, Leigh M. Durden Mar 2023

The Kinetics Of Biocontaminant Inactivation: A Comparative Study With Bacillus Globigii And Bacillus Anthracis, Leigh M. Durden

Theses and Dissertations

Bacillus anthracis has been a biological threat for decades and after the 2001 terrorist attack via the U.S. Postal Service where five people died, there was heightened awareness and inquiry on the subject (Goel, 2015; Greenberg et al., 2010; Nicholson & Galeano, 2003; Spotts Whitney et al., 2003). The health risk to humans makes this biological agent, a Tier 1 agent and one of the most likely to be used in an attack (Anthrax as a Bioterrorism Weapon | CDC, n.d.; Driks, 2009; Rose & Rice, 2014). B. anthracis is one of most resistant and potent biological warfare agents as …


Net Zero Water Air Force Installations, Kenneth R. Mcknight Mar 2023

Net Zero Water Air Force Installations, Kenneth R. Mcknight

Theses and Dissertations

The United States continues to face problems of a reduction in quality and quantity of groundwater sources because water extraction exceeds natural source recharge. The Air Force has recognized the importance of these groundwater sources but has put minimal effort into determining their contribution to the depletion of these sources. The purpose of this study is to determine this contribution by determining whether Air Force installations are net zero water. This is done using a geospatial information system to determine the volume of water recharging groundwater sources associated with an Air Force installation. This volume is then compared to the …


Long-Term Asset Prioritization To Support District Planning, Melissa R. Sallberg Mar 2023

Long-Term Asset Prioritization To Support District Planning, Melissa R. Sallberg

Theses and Dissertations

The United States Air Force (USAF) relies on its installations to project military power across the globe. However, due to the deferred infrastructure maintenance and recapitalization backlog of $33 billion as of 2019 (Wilson & Goldfein, 2019), it is more critical than ever for base-level community planners to focus their attention to the projects that will achieve each installation’s long-term goals. The recent incorporation of asset management principles into the USAF District Planning Process allows a unique opportunity to improve the existing scoring model for a holistic look at what matters to enterprise leaders and community planners making the plans …


Applications Of Fragile Curves To Water Distribution Networks, Danielle M. Van Lanen Mar 2023

Applications Of Fragile Curves To Water Distribution Networks, Danielle M. Van Lanen

Theses and Dissertations

Water distribution networks are of critical importance to provide uninterrupted services to a city. Not only do they provide potable drinking water to customers they also are used for fire services and other emergency support functions. By the year 2039, the United States’ drinking water investment gap is estimated to grow to $136 billion dollars. As the gap between available funding and funding required, being able to prioritize assets for investments is critical. Unfortunately, water distribution networks are typically managed reactively rather than proactively. This paper showcases a methodology for a proactive approach to asset management through the use of …


Arctic Construction Under Climatological Constraints: A Decision Support System For Expeditionary Construction Site Selection In The Arctic Environment, Zachary S. Wontrop Mar 2023

Arctic Construction Under Climatological Constraints: A Decision Support System For Expeditionary Construction Site Selection In The Arctic Environment, Zachary S. Wontrop

Theses and Dissertations

The natural physical barriers present in the Arctic are being eroded by climate change, increasing near peer adversaries' abilities to exploit this region for strategic and economic gain. To maintain the Arctic as a region of strategic and economic international cooperation, increased infrastructure investment by the United States and its allies are required. No methodology currently exists to quantify construction-limiting climatological factors over time and space. Decision support systems can provide actionable information to guide decision makers during site selection. This research employs geographic, and time-coded historical climatology applied to a project case study, to develop a site selection decision …


Civilian And Military Civil Engineer Mission In The Space Domain, Linda E. Kuster Mar 2023

Civilian And Military Civil Engineer Mission In The Space Domain, Linda E. Kuster

Theses and Dissertations

Military and civil interest in space-based operations has increased dramatically in recent years due to the discovery of life sustaining properties such as water on Mars and advancements in cyber technology. Civilian sector discussions and research have centered on the establishment of permanent extraterrestrial infrastructure, while discussions from the military perspective have focused on providing reliable, resilient infrastructure, capable of withstanding cyber-based and kinetic attacks. Both perspectives account for known threats and sustainment methods required to ensure success in the space domain. With the existence of threats for the military and civilian missions, civil engineers will undoubtedly be critical to …


Investigation Of Possible Alternatives To Fossil Fuels For The Dod In Indopacom, Terrence W. Caploe Mar 2023

Investigation Of Possible Alternatives To Fossil Fuels For The Dod In Indopacom, Terrence W. Caploe

Theses and Dissertations

Energy security, greenhouse gas (GHG) emissions, and geopolitical concerns in the south pacific require diversification and independence from legacy energy sources in the Indo-Pacific Combatant Command (INDOPACOM) area of operation (AO). The United States Government has placed mandates and directives to minimize the impacts of GHG on the climate. These orders require divestment from GHG producing fuel sources by 2050. This study compares the energy alternates to Jet Propulsion 8 (JP8) as Ammonia, Hydrogen, and Lithium-ion Batteries. The study uses Life Cycle Assessment (LCA) tools to determine the environmental impacts of various energy candidates in the South Pacific. These results …


Climate-Informed Idf Curve Updates And Impact On Design Policy, Douglas C. Jaks Mar 2023

Climate-Informed Idf Curve Updates And Impact On Design Policy, Douglas C. Jaks

Theses and Dissertations

Stormwater systems across the United States (US) are aging with the American Society of Civil Engineers awarding a grade of D for the state of the infrastructure. Additionally, these aging systems are under-designed for climate-induced non-stationarity of rainfall. Several studies indicate a global increase of extreme rainfall events as a result of climate change, driving the need for future stormwater management designs that account for a changing climate. Specifically, this research generates climate-change informed intensity-duration-frequency (IDF) curve change factors through downscaled climate scenario change factors. While previous work has identified processes for predicting future IDF curves, this study generated curves, …


Decontamination Of Perfluoroalkyl Substances From Stainless Steel Piping Used In Aqueous Film Forming Foam Fire Suppression Systems, Ryan M. Register Mar 2023

Decontamination Of Perfluoroalkyl Substances From Stainless Steel Piping Used In Aqueous Film Forming Foam Fire Suppression Systems, Ryan M. Register

Theses and Dissertations

This study examines the removal of perfluoroalkyl substances (PFAS) from legacy hangar fire suppression systems which utilized PFAS containing aqueous film forming foam (AFFF). Hundreds of these systems are currently in place throughout the Department of Defense, with planned phase-out occurring by 2024. The estimated cost of replacing these systems is $2.1 billion dollars. To mitigate this cost, a triple-rinse method of decontamination has been proposed. This thesis explores the release of PFAS from AFFF systems during a triple-rinse decontamination, and the continued removal of PFAS after a triple-rinse is complete while simultaneously analyzing methylene blue dye as a potential …


Project Selection In Facility And Infrastructure Maintenance Organizations, Bayram M. Kurbanov Dec 2022

Project Selection In Facility And Infrastructure Maintenance Organizations, Bayram M. Kurbanov

Theses and Dissertations

The current Air Force Civil Engineer Center (AFCEC) built infrastructure Facility Sustainment Restoration and Modernization (FSRM) portfolio management methodology results in an unbalanced project portfolio. The consequence of this unbalance is that majority of the funding goes towards buildings on the flightline and Facility Support Services activities do not get adequate funding which leads to further deterioration of those facilities. This research investigates whether decision support framework based on Value-Focused Thinking (VFT) process yields better project selection outcomes for facility and infrastructure maintenance organizations. To accomplish that, the investigation focuses on understanding current AFCEC decision support methodology, building an alternative …


Cost-Benefit Analysis Of The Saudi Land Bridge Project, Faris J. Alotaibi Sep 2022

Cost-Benefit Analysis Of The Saudi Land Bridge Project, Faris J. Alotaibi

Theses and Dissertations

Projects are the backbone of economic thrive of nations, especially infrastructure projects. It’s counted as the base layer of allowing economic trade between beneficiaries. Railway projects have always been a huge element in increasing trade operations between Saudi Arabia and the rest of the world, by providing an efficient and environmentally friendly way that is capable of hauling large loads of exports all the way to the seaports and from there to the rest of the world. The Saudi land bridge project will cost about $11 billion and will provide a new link between the existent railway in the eastern …


Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski Mar 2022

Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski

Theses and Dissertations

Atmospheric Water Generators (AWG) extract water from the air using one of three available technologies: refrigeration, sorption, and fog harvesting. A refrigeration device works like a dehumidifier and works best in conditions above 60% relative humidity. A sorption device utilizes a desiccant to extract the water vapor from the air and works in very low humidity levels. A fog harvesting device utilizes a mesh to capture the water vapor from the air and requires 100% relative humidity. In this research, I analyze two refrigeration-based devices and one sorption-based device and their efficacy in providing supplemental water supply. Due to climatological …


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 Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr. Mar 2022

A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr.

Theses and Dissertations

This thesis is a response to climate threats identified by DoD report on Climate Change in 2019. A critical review of climate change literature related to coastal infrastructure was conducted to synthesize past research and to inform future research. This review intends to inform how climate change may impact infrastructure systems, how those impacts are evaluated, can the investigation be improved, and what can stakeholders learn from the outcomes. The end goal is to find climate change mitigation strategies and adaptation measures, or identify the easiest path to get to that end. The compiled information will inform civilian and military …


Prioritizing Water Distribution Network Asset Maintenance Using Graph Theory Methods, Ashton E. Doyal Mar 2022

Prioritizing Water Distribution Network Asset Maintenance Using Graph Theory Methods, Ashton E. Doyal

Theses and Dissertations

Water distribution networks, like any other large infrastructure system, should be designed for reliability and resilience to resist failure. A literature review of graph theory methods pertaining to water distribution networks reveals a wide scope of mathematical and statistical measures that can be used to identify and classify many important features of a network. From this, an analysis using a combination of graph theory metrics and generated condition indices for the pipes is performed on the Tyndall drinking water system as a case study. The goal is to provide understanding to the risk of the current system and propose asset …


Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej Mar 2022

Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej

Theses and Dissertations

This thesis aims to contribute to the future development of this technology by providing an in-depth literature review of how this technology physically operates and can be numerically modeled. Additionally, this thesis reviews literature of machine learning models that have been applied to gasification to make accurate predictions regarding the system. Finally, this thesis provides a framework of how to numerically model an experimental plasma gasification reactor in order to inform a variety of machine learning models.


Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald Mar 2022

Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald

Theses and Dissertations

The persistence, fate, and transport of per- and poly-fluoroalkyl substances, which have been shown to have adverse effects on human health, have been previously studied in environmental media such as soils and groundwater. This study investigates concrete, a medium that is rarely studied but frequently present in instances where PFAS originating from AFFF releases and spills have occurred. Used heavily throughout aviation firefighting, AFFF poses environmental hazards due to the length of PFAS degradation and toxicological implications, thus its classification as a forever chemical. From the very limited reports to date, studies have suggested very slow release from concrete, potentially …


A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik Mar 2022

A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik

Theses and Dissertations

Intensifying extreme weather events, tied to the rise in the global average temperature, put global built infrastructure at risk. This presents a daunting challenge for organizational leaders who are tasked to determine how best to adapt current infrastructure to uncertain future events. To develop adaptation plans and policies, vulnerability and risk must be downscaled to an actionable scale, such that planners, designers, and engineers can make adaptation recommendations. However, previous research has largely assessed risk at coarser scales, e.g., regional, national, or global. These assessments are informative, but do not help those tasked to lead adaptation to make detailed, actionable …


Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray Mar 2022

Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray

Theses and Dissertations

Recent executive orders and international agreements require the United States to significantly reduce its carbon and greenhouse gas emissions. The DoD is a significant contributor to the carbon emissions of the USA and will be required to reduce the emissions. Therefore, in order to make appropriate programmatic decisions the DoD needs to develop an appropriate method for estimating carbon and making programmatic decisions; trading-off carbon emissions with the traditional cost-schedule-performance metrics. This thesis examines the possibility of developing a model that can be used to estimate the carbon footprint of producing a system before detailed engineering designed have been complete.


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 …


Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance Mar 2022

Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance

Theses and Dissertations

Hurricane frequency and magnitude intensification are expected over the remainder of the twenty-first century. Uncertainty in future projections requires that coastal communities approach adaptation decisions with caution. Traditional approaches are costly and inflexible. Soft policy adaptations are largely unenforceable. Hard, natural adaptations have emerged as an opportunity to partially mitigate the growing risk of extreme flooding, without the large investments required for traditional approaches, where natural infrastructure already exists. Existing literature for natural adaptations has not leveraged intensification expectations for hurricane events. This research uses multihazard damage evaluation software and spatial analysis to investigate placement of dredged sediment as a …


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 …


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.


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 …