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Full-Text Articles in Physical Sciences and Mathematics

Filter-Based Air Sampler Capable Of Integration Into Small Unmanned Aerial Vehicles, Robert M. Eninger, Stepanie A. Ohms, Jeremy M. Slagley Apr 2023

Filter-Based Air Sampler Capable Of Integration Into Small Unmanned Aerial Vehicles, Robert M. Eninger, Stepanie A. Ohms, Jeremy M. Slagley

AFIT Patents

A filter-based air sampler, more specifically a filter-based air sampler capable of integration into small unmanned aerial systems is disclosed. The filter-based air sampler may include a filter assembly which has as its component parts: an open faced air intake component, a filter, and a filter support that has a central supporting grid. The filter assembly may joined to the housing of a fan, such as a centrifugal fan, with the supporting grid of the filter support being disposed over the air inlet of the fan.


A Comparative Analysis Of Viral Aerosol Biological Sampling Efficiency Of A Small Unmanned Aircraft System (Suas)-Mounted Aerosol Sampler And A Reference Static Biosampler®, Jonathan D. Moroz Mar 2023

A Comparative Analysis Of Viral Aerosol Biological Sampling Efficiency Of A Small Unmanned Aircraft System (Suas)-Mounted Aerosol Sampler And A Reference Static Biosampler®, Jonathan D. Moroz

Theses and Dissertations

Bioaerosol sampling using small unmanned aerial systems (sUAS) is a rapidly developing field that may result in a paradigm shift in emergency response and industrial hygiene sampling conventions. These technologies offer decreased sample acquisition times, larger sampling area coverage, and reduced health and safety risks to traditional human sampling teams. This potential requires a comprehensive investigation of sUAS capabilities and limitations. This study is a continuation of the characterization of an AFIT-developed sUAS-mounted aerosol sampler, proven capable of collecting viable vegetative and spore-forming bacteria through previous AFIT research. Within this study, viral biological sampling efficiency (BSE) of the sUAS-mounted aerosol …


Crop Circles In The Corn Belt: A Farm-Scale Model To Curb Future Crop Yield Loss With Blended Policy-Structural Adaptations, Daniel Ress Mar 2021

Crop Circles In The Corn Belt: A Farm-Scale Model To Curb Future Crop Yield Loss With Blended Policy-Structural Adaptations, Daniel Ress

Theses and Dissertations

In today's rainfed agricultural regions farmers reliably produce marketable yields without the need for irrigation technology or specific planting policies. However, climate change is expected to challenge global food security. As a result, farmers might seek adaptation strategies. This research investigates the spatiotemporal suitability of blended policy-structural adaptations to reduce yield losses in Greene County, Ohio. A crop-water model is used to calibrate and generate field-scale yield predictions. The resultant framework holds the potential to inform farmer and county-level decision making under future climate uncertainty, and it illustrates the tradeoffs between adaptation cost and yield security.


Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding Mar 2021

Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding

Theses and Dissertations

Legacy per- and polyfluoroalkyl substances (PFASs) exist in the form of aqueous film-forming foams within hangar fire suppression systems throughout the country, posing a threat to both surrounding environments as well as local populations. The United States (US) Department of Defense (DoD), in conjunction with the US Environmental Protection Agency (EPA), is investigating best practices to flush out existing contaminants prior to disposal and replacement with a less environmentally harmful replacement. While current procedures dictate a triple rinse of the entire system to yield contaminant levels acceptable to the DoD, the practice has never truly been tested. Designed as a …


Analysis Of Pollution Prevention Business Case Analyses, Erwin A. Spencer Jr. Mar 2021

Analysis Of Pollution Prevention Business Case Analyses, Erwin A. Spencer Jr.

Theses and Dissertations

The purpose of this research is to improve the Business Case Analysis (BCA) process in the context of pollution prevention. The research will inform guidance, training, and policy recommendations. Using grounded theory methods allowed us to gather qualitative data directly from participants actively involved in pollution prevention projects. In addition to answering several research questions, the results of the research informed the design of a tool to help government and contractor personnel agree on what constitutes a high-quality BCA. This research has implications for DoD decision making and future studies in environmental cost analysis.


Characterization And Analysis Of Bomarc Accident Debris, Aaron J. Heffelfinger Mar 2021

Characterization And Analysis Of Bomarc Accident Debris, Aaron J. Heffelfinger

Theses and Dissertations

Accidents involving nuclear weapons, such as the Boeing Michigan Aeronautical Research Center (BOMARC) accident in 1960, always pose a significant risk of allowing particles composed of nuclear materials to enter the environment. These particles often differ in characteristics and can be of greatly varying sizes. Gamma ray analysis was conducted on the soil sample and radioisotopes within the sample were identified. Two non-destructive methods for locating actinide bearing particles within the sample were testing, resulting in 70 actinide bearing particles ranging from 1-34 microns being identified. These 70 particles underwent both morphological and elemental characterization, indicating uranium and other elements.


Quantifying Permafrost Extent, Condition, And Degradation At Eielson Air Force Base, Theodore J. Labedz Mar 2019

Quantifying Permafrost Extent, Condition, And Degradation At Eielson Air Force Base, Theodore J. Labedz

Theses and Dissertations

The DoD is executing over $500M in military construction on Eielson Air Force Base (AFB) within the next three years. This construction program will expand the footprint of facilities and change parts of the storm water management scheme, which may have second order effects on the underlying permafrost layers. These changes in permafrost will drive engineering decision, and help shape the overall strategy for military readiness in the Arctic. Little site-specific knowledge exists on the human caused effects to permafrost at this location. In 2016, the permafrost degradation rates at Eielson AFB were modeled using the Geophysical Institute Permafrost Laboratory …


The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski Mar 2017

The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski

Theses and Dissertations

The Department of Defense is planning over $552M in military construction on Eielson Air Force Base within the next three fiscal years. Although many studies have been conducted on permafrost and climate change, the future of our climate as well as any impacts on permafrost soils, remains unclear. This research focused on future climate predictions to determine likely scenarios for the United States Air Force’s Strategic Planners to consider. The most recent 2013 International Panel on Climate Change report predicts a 2.2ºC to 7.8ºC temperature rise in Arctic regions by the end of the 21st Century in the Representative Concentration …


Environmental Applications Of Small Unmanned Aircraft Systems In Multi-Service Tactics, Techniques, And Procedures For Chemical, Biological, Radiological, And Nuclear Reconnaissance And Surveillance, Brandon B. Barnes Mar 2017

Environmental Applications Of Small Unmanned Aircraft Systems In Multi-Service Tactics, Techniques, And Procedures For Chemical, Biological, Radiological, And Nuclear Reconnaissance And Surveillance, Brandon B. Barnes

Theses and Dissertations

Small unmanned aircraft systems can be used for a variety of environmental applications. SUAS under 50 kg have the most utility at the tactical level and benefit from the research and development of systems currently being manufactured. Integrating chemical sensors into these systems can enhance Multi-service Tactics, Techniques, and Procedures for Chemical, Biological, Radiological, and Nuclear Reconnaissance and Surveillance. Considering the advantages and disadvantages in the fundamental science of twelve detection technologies, four types of sensors emerged as candidates for SUAS integration. Using specifications from commercial-off-the-shelf sensors, these four detection technologies (Electrochemical, Metal Oxide Semiconductor, Photoionization, and Catalytic Bead) were …


A Simulation-Based Analysis Of Chemical And Radiological Hazard Zones Adapted To Physical Boundaries, Mickie J. Sundheim Mar 2016

A Simulation-Based Analysis Of Chemical And Radiological Hazard Zones Adapted To Physical Boundaries, Mickie J. Sundheim

Theses and Dissertations

In the United States, industrial and terrorist use of chemical, biological, radiological, and nuclear (CBRN) materials pose a risk to public safety. During the initial phase of typical CBRN incidents, emergency responders establish hazard zones based on standard distances from published guidelines and recommendations. This research investigates how standard hazard zones change in a real world environment that accounts for physical boundaries. Using a python simulation in ArcGIS®, new hazard zones were created by expanding standard hazard zones to follow nearby roads, railroads, and rivers. The new and standard zones were compared by calculating the population and area affected by …


Upward Flow Constructed Wetland For Treatment Of Water Contaminated With Chlorinated Aliphatics, Michael Shelley, Abinash Agrawal, Ke Qin, Garrett Struckhoff, Carl Enfield, James Waldron, Christina Powell Nov 2014

Upward Flow Constructed Wetland For Treatment Of Water Contaminated With Chlorinated Aliphatics, Michael Shelley, Abinash Agrawal, Ke Qin, Garrett Struckhoff, Carl Enfield, James Waldron, Christina Powell

AFIT Patents

An improved upward flow constructed wetland cell for treatment of water contaminated with chlorinated aliphatics is disclosed. The improvements include adding ammonia-oxidizing microorganisms to the methane-oxidizing microorganisms already present in an oxygenated root zone and adding improved pore-water sample chambers for measuring the performance of the constructed wetland cell.


Prototyping The Use Of Dispersion Models To Predict Ground Concentrations During Burning Of Deployed Military Waste, Val Oppenheimer Mar 2012

Prototyping The Use Of Dispersion Models To Predict Ground Concentrations During Burning Of Deployed Military Waste, Val Oppenheimer

Theses and Dissertations

United States military forces in Iraq and Afghanistan have often used open burning of solid waste as a means to achieve volume reduction and to minimize vector borne illnesses. Assessing exposures to burn pit emissions has proven challenging, requiring significant numbers of personnel and sampling equipment. This study examined the use of three common dispersion models to determine the feasibility of using software modeling to predict short-range exposures to burn pit emissions, in lieu of sole reliance on ground sampling. Four open burn tests of municipal solid waste were conducted at Tooele Army Depot, Utah. Aerial samples were collected above …


Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall Mar 2012

Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall

Theses and Dissertations

U.S. military forces have relied primarily on open burning as an expedient method of volume reduction and treatment of solid waste during the conflicts in Afghanistan and Iraq. This study is the first effort to characterize a broad range of pollutants and their emission factors during the burning of military waste and the effects that recycling efforts, namely removing plastics, might have on emissions. Piles of simulated military waste were constructed, burned, and emissions sampled at the U.S. Environmental Protection Agency (EPA) Open Burn Testing Facility (OBTF), Research Triangle Park, NC. Three tests contained polyethylene terephthalate (PET #1 or PET) …


An Evaluation Of A Networked Radiation Detection System, Leif A. Hansen Mar 2010

An Evaluation Of A Networked Radiation Detection System, Leif A. Hansen

Theses and Dissertations

First responders assess a Nuclear/Radiological (NUCRAD) event in a timely and accurate manner by creating a site characterization that reflects the location of various levels of contamination based on their instruments’ readings. The survey team experiences difficulty in accurately recording this critical data due to the challenge of operating multiple devices and communicating the devices’ readings to other survey members. First responders produce a representation of the contamination or activity on a map that contain rings outlining the levels of activity and/or single locations of a single activity. Recently, several agencies began creating software programs that record a first responder’s …


Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz Mar 2007

Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz

Theses and Dissertations

This research determined the rate and extent of aerobic biodegradation of fuel oxygenates ethyl tert butyl ether (ETBE), tert amyl methyl ether (TAME), and ethyl alcohol (ethanol). Biodegradation was measured using gas chromatography (GC), respirometry, and biochemical oxygen demand (BOD) tests. Additionally, the research determined the effects of toluene on degradation rates. This microcosm study used a microbial consortium obtained from a petroleum refinery wastewater treatment facility. Respirometry data were collected from chambers containing pure oxygenates, or oxygenate/toluene mixtures. Samples were withdrawn periodically for GC analysis. Aerobic conditions were maintained in the chambers at all times. The five-day BOD test …


Comparative Analysis Of Biosurveillance Methodologies, David M. Kempisty Mar 2006

Comparative Analysis Of Biosurveillance Methodologies, David M. Kempisty

Theses and Dissertations

The purpose of this research is to compare two different biosurveillance methodologies: BioWatch and "A Hot Idea". BioWatch is fielded and operating in major US cities today. Air samples are collected on filter paper and analyzed for the presence of harmful biological agents. "A Hot Idea" is an evolving methodology using the human body's immune response to identify the onset of infection from a harmful pathogen. Detecting a temperature increase, using infrared thermographers, in a statistically significant portion of population would allow earlier identification of a biological release, accelerating initiation of response actions. A selected population including policemen, firemen, and …


Validation Of Methods To Measure Mass Flux Of A Groundwater Contaminant, Hyouk Yoon Mar 2006

Validation Of Methods To Measure Mass Flux Of A Groundwater Contaminant, Hyouk Yoon

Theses and Dissertations

In this study, flux measurements obtained using two methods are compared with known mass fluxes in a meso-scale three-dimensional artificial aquifer. One method, the tandem recirculating well (TRW) method, is applied using two different techniques. One technique is simple and inexpensive, only requiring measurement of heads, while the second technique requires conducting a tracer test. The second method, the integrated pump test (IPT) method, requires use of one or more pumping and observation wells in various configurations. The results of the experiments in the artificial aquifer show that the most expensive technique, the TRW method using tracers, provides the most …


Characterization Of Microbial Processes That Degrade Chlorinated Solvents In A Constructed Wetland Using Organic Acid And Inorganic Anion Concentration Profiles, Chad B. Bondurant Mar 2004

Characterization Of Microbial Processes That Degrade Chlorinated Solvents In A Constructed Wetland Using Organic Acid And Inorganic Anion Concentration Profiles, Chad B. Bondurant

Theses and Dissertations

Chlorinated solvents have been used in industrial cleaning and degreasing processes in the United States since the early 1900s, and their induction into the environment increased significantly with the growth of industrial processes over the past century. PCE, TCE and their daughter products have been associated with a number of human health concerns and are currently the most common contaminants found in groundwater in the United States. Wetlands possess characteristics necessary for the complete degradation of chlorinated ethenes by microorganisms via anaerobic and aerobic regions that foster the necessary oxidation-reduction conditions. Organic acid and inorganic anion concentrations were evaluated in …


Remote Sensing Systems Optimization For Geobase Enhancement, Steve J. Paylor Mar 2003

Remote Sensing Systems Optimization For Geobase Enhancement, Steve J. Paylor

Theses and Dissertations

The U.S. Air Force is in the process of implementing GeoBase, a geographic information system (GIS), throughout its worldwide installations, Air Force GIS needs can be augmented by imagery from aerial and satellite platforms. Imagery has greatly improved over the past several years and provides high resolution coverage of features on earth. Various imagery types will significantly increase GeoBase usefulness in a range of mission requirements, Potential Air Force uses of imagery include identifying heat loss, environmental monitoring, command decision-making, and emergency response, The research develops a decision tool to determine the appropriate imagery for a given Air Force Application, …


A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates Mar 2003

A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates

Theses and Dissertations

The red-cockaded woodpecker (Picoides borealis) is classified under the Endangered Species Act of 1973 as an endangered species As such, the red-cockaded woodpecker (RCW) is afforded strict protection in an effort to return the RCW population to a self-sustainable level. Endemic to southeastern United States mature pine forests, the presence of the RCW impacts the operations of many Department of Defense (DoD) installations. A particular challenge in sustaining what are often small populations of RCW at these locations is the loss of genetic variation due to genetic drift. The optimal method for mitigating such loss is through the artificial immigration, …


Evaporation Of Jet Fuels, Charles Eric Hack Dec 1999

Evaporation Of Jet Fuels, Charles Eric Hack

Theses and Dissertations

Determining the fate and transport of JP-8 jet fuel is a complex and important problem. As part of the startup procedures for jet engines, fuel is passed through aircraft engines before combustion is initiated. Because of the extremely low temperatures at northern tier Air Force bases, the unburned fuel does not evaporate readily and may come into contact with ground crew. To determine the amount and duration of contaminant contact, the evaporation of the emitted fuel must be modeled. The amount and composition of the fuel upon reaching the ground crew may be determined by droplet evaporation models that have …


The Fate And Transport Of Airborne Jp-4 And Jp-8 Aerosol During Cold Startup, Bradford Eugene Buckman Dec 1997

The Fate And Transport Of Airborne Jp-4 And Jp-8 Aerosol During Cold Startup, Bradford Eugene Buckman

Theses and Dissertations

During cold startup (engine warm-up) procedures at northern tier bases, fuel aerosol (JP-4 and JP-8) is emitted before complete combustion of the fuel occurs. The time necessary for complete combustion to occur may be as long as 10 minutes. Hence, during these first few minutes, aerosol is emitted at relatively high concentrations. This research investigates the principle behavior of the emitted aerosol: advection, dispersion, evaporation, and settling. Using previous work in fuel jettisoning and evaporation as a foundation, this thesis investigates the physical factors affecting the airborne concentration of fuel aerosol at different times, the amount of fuel aerosol reaching …


A System Dynamics Model Of The Bioavailability Of Metals In Constructed Wetland Sediment, Timothy S. Wood Dec 1997

A System Dynamics Model Of The Bioavailability Of Metals In Constructed Wetland Sediment, Timothy S. Wood

Theses and Dissertations

Constructed wetlands used for storm water treatment accumulate metals primarily in their sediment. This sediment has the potential to produce toxic effects in benthic organisms at some period in time. Bioavailability of metals in sediment is directly linked to pore water metal activity. The mechanisms that influence pore water metal activity are included in physical, chemical, and biological processes. A system dynamics model was developed to represent these processes and the major influences affecting pore water metal activity in a treatment wetland receiving storm water influent. The model structure and behavior was tested and validated using several system dynamics validation …


Modeling Uptake And Translocation Of Lead (Pb) In Maize For The Purposes Of Phytoextraction, Mark A. Brennan Dec 1997

Modeling Uptake And Translocation Of Lead (Pb) In Maize For The Purposes Of Phytoextraction, Mark A. Brennan

Theses and Dissertations

Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. This technology has the potential to decrease the costs of remediating contaminated sites by several orders of magnitude compared to traditional technologies. To effectively implement this technology requires an understanding of the plant processes that control uptake and translocation of metals from the soil. Currently these processes are poorly understood, and especially so for Pb. The purpose of this thesis was to gain insights concerning the plant mechanisms that control uptake and translocation of Pb and how these mechanisms interact to control levels of Pb accumulation …


Surfactant Enhanced Microbial Degradation Of Jp-8 Contaminated Soil, John D. Thomas Dec 1996

Surfactant Enhanced Microbial Degradation Of Jp-8 Contaminated Soil, John D. Thomas

Theses and Dissertations

This research effort used an automated respirometer to evaluate the enhancement of JP-8 fuel biodegradation, from surfactant addition. Two nonionic surfactants, Novell 1412-7 and Alfonic 810-4.5 were chosen for addition to contaminated JP-8, microcosms at three levels of treatment. The three levels of treatment included sub-CMC, CMC, and supra-CMC concentrations for each surfactant. The Novell II, nonionic surfactant, exhibited inhibitory characteristics, and was eliminated from the study. The focus of the study was to determine if JP-8 was actually degraded, and if enhancement of JP-8 biodegradation would be achieved from surfactant addition. The respirometer was found to be repeatable within …


Local Effects Of Solid Rocket Motor Exhaust On Stratospheric Ozone Concentrations, Brian K. George Dec 1996

Local Effects Of Solid Rocket Motor Exhaust On Stratospheric Ozone Concentrations, Brian K. George

Theses and Dissertations

Solid Rocket Motors (SRMs) power the initial flight of the Space Shuttle and Titan IV rocket. During those first two minutes after liftoff, the exhaust plumes from these motors emit large quantities of chlorine compounds and alumina particles into the atmosphere. For years scientists have argued that such a large chlorine input, injected directly into the stratosphere, would photochemically react with the surrounding air to cause significant ozone depletion. To answer the question of whether SRM exhaust causes a significant ozone depletion, Version 7 data from the Total Ozone Mapping Spectrometer (TOMS) instrument was analyzed for the 30 days prior …


The Biodegradation Characteristics Of Proposed Fuel Systems Icing Inhibitors (Fsii), Charles E. Meshako Dec 1996

The Biodegradation Characteristics Of Proposed Fuel Systems Icing Inhibitors (Fsii), Charles E. Meshako

Theses and Dissertations

The biodegradation characteristics of three fuel system icing ihhibitors (FSII) were evaluated. FSII are jet fuel additives that partition into water readily and are present in the water drained from storage tank bottoms in concentrations approaching 40%. These concentrations raise concerns as to the disposal and handling of these wastes. The current FSII, DiEGME was evaluated along with two new candidates, dipropylene glycol and glycerol formal. DiEGME appeared to be moderately but not completely biodegradable. It is likely that much of it would be removed in a wastewater treatment plant. Dipropylene glycol only showed signs of degradation after more than …


Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman Dec 1996

Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman

Theses and Dissertations

Laser-induced breakdown spectroscopy (LIBS) is a spectroscopic technique where output from a pulsed laser is focused onto a target in order to create an intense plasma. The optical emission is characteristic of the elements in the focal volume and can be used for elemental analysis. Research on the detection of nickel in solution in addition to solvent detection of CCl4, CHCl3, C2Cl4, and C2HCl3 has been performed. Breakdown was formed at the sample surface via a Q-switched Nd:YAG laser. Initially, operation of the laser was at 1064 nm/repetition rate of 5 Hz. Experiments …


Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner Dec 1996

Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner

Theses and Dissertations

Volatile organic compounds (VOCs) dissolved in the saturated zone are transported into the vadose zone primarily by gaseous phase diffusion. If the saturated zone is remediated, VOCs present in the vadose zone may become a secondary source of contamination for the groundwater. The amount of VOCs that remain in the vadose zone is dependent on site hydrology, soil properties, and the chemical properties of the contaminants. The purpose of this study was to determine what conditions caused VOC concentrations in the vadose zone to significantly recontaminate the saturated zone. A one-dimensional numerical model was developed to investigate the transport of …


Evaluating The Hazardous Materials (Hazmat) Pharmacy Among Air Force Majcoms Using Waste Reductions And Activity Indicators, W. Edward Iseman Jr. Dec 1996

Evaluating The Hazardous Materials (Hazmat) Pharmacy Among Air Force Majcoms Using Waste Reductions And Activity Indicators, W. Edward Iseman Jr.

Theses and Dissertations

The Hazardous Materials (HazMat) Pharmacy has been designed as an environmentally friendly vehicle to handle, store, dispense, track, recycle, and dispose of hazardous materials in the Air Force. This thesis effort proposed a method in which valuable feedback for the pharmacy can be obtained. Because it is still in the early stages of implementation, there has been little feedback on the pharmacy. An activity index that uses a variable most closely associated with the generation of hazardous waste in a MAJCOM is proposed. Using an aircraft maintenance related variable, like maximum take-off weight, the fluctuations in mission over time can …