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Modeling Study To Quantify The Benefits Of Groundwater Contaminant Source Remediation, David E. Wagner Mar 2006

Modeling Study To Quantify The Benefits Of Groundwater Contaminant Source Remediation, David E. Wagner

Theses and Dissertations

The purpose of this research was to quantify the benefits of groundwater contaminant source remediation by using a model to simulate how reduction of source mass was related to reduction of contaminant concentration at a receptor. This thesis sought to answer three research questions: (1) how are contaminant source mass reduction and reduction of mass flux leaving the source-zone related; (2) how can we quantify the effect of the important natural attenuation processes that act upon the dissolved contaminant as it travels from the source zone to downgradient receptors, and (3) under specified site conditions, what is the maximum contaminant …

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Efficient And Accurate Computation Of Elastic Cross Sections In The Single-Level Breit-Wigner Resonance Region, Edward L. Hobbs Mar 2006

Efficient And Accurate Computation Of Elastic Cross Sections In The Single-Level Breit-Wigner Resonance Region, Edward L. Hobbs

Theses and Dissertations

The use of piecewise cubic Hermite polynomials to approximate resonance region cross sections provides a means to accomplish the same task with increased accuracy and fewer points that require exact cross section calculation. Once the derivative of the cross section formula is derived and the interpolating cubic is appropriately shifted and scaled for numerical stability, use of the piecewise cubic Hermite polynomial is easily inserted into computer codes that depend on cross section calculation in the resonance energy region.

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A Meaning-Based Instruction To Enhance Literacy Learning In A Dual-Language Kindergarten Classroom, Megan Melissa Fife Mar 2006

A Meaning-Based Instruction To Enhance Literacy Learning In A Dual-Language Kindergarten Classroom, Megan Melissa Fife

Theses and Dissertations

Concerns among educators continue to grow with the increased enrollment of Second Language Learners (SLL) in classrooms throughout the United States. This influx has stressed the boundaries of current methods of literacy instruction, which are not designed to meet the needs of these at-risk students. Literacy instructional methods need to be remediated through early intervention, followed by effective literacy instruction that is designed to meet the specific needs of SLL. Effective literacy instruction overcomes differences in culture and background by using meaning-based instruction coupled with engaging and varied contexts. This study evaluated the effectiveness of incorporating meaning-based instructional activities into …

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The Personal Impact On Female Therapists From Working With Sexually-Abused Children, Kinsey Drouet Pistorius Mar 2006

The Personal Impact On Female Therapists From Working With Sexually-Abused Children, Kinsey Drouet Pistorius

Theses and Dissertations

Although previous research has established that therapists who work with sexually-abused children experience symptoms of vicarious trauma, few studies have addressed the process by which the therapist is affected. In order to understand therapists' personal experiences and how working with sexually-abused children impacts them in their personal lives, the researcher interviewed therapists who were currently working with this specific population. Data analysis was completed by using ethnographic research methods and three major themes emerged during the interviews. The first theme included the "job characteristics" inherent in working with sexually-abused children. This theme refers to how the therapists entered the field …

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An Evaluation Of How Organizational Culture Can Perpetuate A Formal Mentoring Relationship, Daniel J. Rieker Mar 2006

An Evaluation Of How Organizational Culture Can Perpetuate A Formal Mentoring Relationship, Daniel J. Rieker

Theses and Dissertations

The purpose of this research was to investigate how an organization's culture can have an effect on formal mentoring. Specifically, this thesis sought to determine if perceptions among gender, ethnicity, and organizational position differ for mentoring and organizational culture. Additionally, this thesis sought to determine if any correlations may exist between organizational culture and formal mentoring overall.

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Evaluation Of Chlorinated Solvent Removal Efficiency Among Three Wetland Plant Species: A Mesocom Study, Jun Yan Mar 2006

Evaluation Of Chlorinated Solvent Removal Efficiency Among Three Wetland Plant Species: A Mesocom Study, Jun Yan

Theses and Dissertations

Different species of plants need to be studied individually to compare the remediation efficiency of each species. This research will study three different wetland plants species and an unplanted control, under a laboratory setting. Each plant has a different characteristic favorable for chlorinated solvent degradation. Eleocharis erythropoda (Spike Rush) are plants with thin tube like leaves and large root mass. Carex comosa (Bearded Sedge) has broad leaves and Scirpus atrovirens (Green Bulrush) are broad leafed wetland plants with a long flowering stem during reproduction. PCE will be injected into the plant mesocosm and any possible PCE degradation will be observed. …

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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 …

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An Analysis Of Usaf Aircraft Noise And Hedonic Property Values, Melissa R. Johnson Mar 2006

An Analysis Of Usaf Aircraft Noise And Hedonic Property Values, Melissa R. Johnson

Theses and Dissertations

The primary purpose of the research was to evaluate whether there was a significant difference in housing values of those affected by the noise of USAF aircraft. The secondary purpose was to evaluate whether there was a significant difference in housing values located near USAF bases with and without aircraft noise and to evaluate whether type of aircraft changed the results created by the aircraft noise. This research effort found that homes located within the 65 dB DNL contour of US Air Force installations showed a significant negative impact due to the presence of aircraft noise when studied with the …

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Modeling E & F Region Ionospheric Response To X-Ray Solar Flares, Annette M. Parsons Mar 2006

Modeling E & F Region Ionospheric Response To X-Ray Solar Flares, Annette M. Parsons

Theses and Dissertations

This research takes an existing ionospheric model and modifies it to include the effects of solar flare activity. Solar flares are a localized explosive release of magnetic energy that appears as a sudden, short-lived brightening in the sun’s chromosphere. This additional energy is deposited in the earth’s ionosphere, temporarily changing its properties, which can affect military communications. Studying the effects of moderate solar flares will improve our understanding of the ionosphere’s response, leading to better operational models. Modification of the model is accomplished by adding a flare irradiance model to represent solar irradiance changes due to a flare. The irradiance …

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Prediction Of Flight-Level Radiation Hazards Due To Solar Energetic Protons, Matthew P. Sattler Mar 2006

Prediction Of Flight-Level Radiation Hazards Due To Solar Energetic Protons, Matthew P. Sattler

Theses and Dissertations

The radiation environment at aircraft altitudes is caused primarily by high-energy particles originating from outside the near-earth environment. These particles generally come from outside our solar system and are called galactic cosmic rays. Occasionally however, a transient solar event will also accelerate energetic protons toward the earth. If these protons reach the upper atmosphere, they produce secondary particles via collisions, resulting in increased radiation levels in the atmosphere. Air crews and electronic systems flying at high altitudes during one of these events are subjected to these increased levels of radiation which can result in health problems for personnel and soft …

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Terrain And Spatial Effects On Hazard Prediction And Assessment Capability (Hpac) Software Dose-Rate Contour Plot Predictions As Compared To A Sample Of Local Fallout Data From Test Detonations In The Continental United States, 1945-1962, Kevin D. Pace Mar 2006

Terrain And Spatial Effects On Hazard Prediction And Assessment Capability (Hpac) Software Dose-Rate Contour Plot Predictions As Compared To A Sample Of Local Fallout Data From Test Detonations In The Continental United States, 1945-1962, Kevin D. Pace

Theses and Dissertations

Hazard Prediction and Capability (HPAC) Software is validated by comparing modeled predictions to historical test data. Reanalysis weather data is acquired and reformatted for use in HPAC. Simulations are made using various amounts of weather data by use of a spatial domain. Simulations are also varied by levels of terrain resolution. The predicted output of the software is numerically compared to historical test data. The result of this research culminated in the knowledge that HPAC prediction accuracy is improved by using terrain resolutions beyond the flat earth assumption. Furthermore, this research establishes that domain size variation produces no significant advantage …

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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 …

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An Exploration Of The Effects Of Genetic Drift On The Endangered Red-Cockaded Woodpecker, Ryan E. Nelson Mar 2006

An Exploration Of The Effects Of Genetic Drift On The Endangered Red-Cockaded Woodpecker, Ryan E. Nelson

Theses and Dissertations

The Red-cockaded Woodpecker (RCW) (Picoides borealis) is classified as an endangered species under the Endangered Species Act of 1973 due to habitat fragmentation and prescribed burn suppression. Given the endangerment of the RCW, the genetic variation of the small populations will decrease over time due to random genetic drift. The only method of battling the negative effects of random genetic drift is to move, or translocate, genetically diverse birds into the fragmented populations thereby increasing the genetic diversity of the small populations. The objective of this research effort was to explore the effects of random genetic drift on small RCW …

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Formal Mitigation Strategies For The Insider Threat: A Security Model And Risk Analysis Framework, Jonathan W. Butts Mar 2006

Formal Mitigation Strategies For The Insider Threat: A Security Model And Risk Analysis Framework, Jonathan W. Butts

Theses and Dissertations

The advancement of technology and reliance on information systems have fostered an environment of sharing and trust. The rapid growth and dependence on these systems, however, creates an increased risk associated with the insider threat. The insider threat is one of the most challenging problems facing the security of information systems because the insider already has capabilities within the system. Despite research efforts to prevent and detect insiders, organizations remain susceptible to this threat because of inadequate security policies and a willingness of some individuals to betray their organization. To investigate these issues, a formal security model and risk analysis …

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Usability And Accessibility Of Air Force Intranet Web Sites, Richard S. Bentley Mar 2006

Usability And Accessibility Of Air Force Intranet Web Sites, Richard S. Bentley

Theses and Dissertations

The Air Force is moving to a network centric environment where information must be data visible, accessible, and understandable. This transformation has seen the adoption of the Internet web browser as a de facto standard for information access. The Technology Acceptance Model suggests that information systems must not only be useful but also be usable and a large body of usability engineering knowledge exists to support usable design. In addition, the U.S. government mandates specific minimum design features required to support disabled user access. This research effort seeks to establish an understanding of how well common practice usability design principles …

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An Epidemiological Approach To Terrorism, Kjirstin A. Bentson Mar 2006

An Epidemiological Approach To Terrorism, Kjirstin A. Bentson

Theses and Dissertations

There are many types of models for counterterrorism, explaining different problems that the military faces in the fight against terrorism. This thesis proposes that one of the fundamental assumptions underlying existing models of counterterrorism is that the struggle with terrorists can be understood as a war in the traditional sense of the term. We propose to rethink the struggle against terrorism as a fight against an infection. The epidemic of terrorist ideology within part of the world is a result, from this perspective, of the infectiousness of that ideology. Using the insights of the field of the epidemiology of ideas, …

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Quantitative Analysis Of A Turbulent Wind Tunnel With Obstructions For Use In Liquid Flame Spread Experiments, Beau M. Brantley Mar 2006

Quantitative Analysis Of A Turbulent Wind Tunnel With Obstructions For Use In Liquid Flame Spread Experiments, Beau M. Brantley

Theses and Dissertations

The research was done as part of an effort to develop alternative fire suppressant technologies for aircraft engine nacelles. The turbulent shear flow behind a surface mounted fence inside an open circuit wind tunnel was investigated experimentally. The tunnel test section was designed to be 2-D and exhibit flow qualities similar to those found in a typical engine nacelle. A 279 mm wide fuel pan was inserted approximately four fence heights downstream of the fence location. The fuel pan was filled using water to simulate fuel with a depth of 32 mm. Cold flow tests were done on different fence …

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Using Value-Focused Thinking To Evaluate The Practicality Of Porous Pavement Parking Areas On Air Force Installations, Christopher D. Bulson Mar 2006

Using Value-Focused Thinking To Evaluate The Practicality Of Porous Pavement Parking Areas On Air Force Installations, Christopher D. Bulson

Theses and Dissertations

Natural runoff processes have been altered by urban development; impervious surfaces (rooftops, highways, parking areas) and their associated storm water systems channel runoff from a vast area into one concentrated outflow. This storm water runoff can cause erosion, flooding, landslides, and significant damage to aquatic ecosystems. Runoff from highways and parking areas has also been known to contain high levels of suspended solids, heavy metals and hydrocarbons. Porous pavements allow infiltration of water through typically impervious surfaces, reducing storm water volumes and acting as a pollutant filtration system. Since there is currently no methodology for Air Force decision-makers to compare …

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Building A Consensus Forecast For Crude Oil Prices, Kenneth W. Burke Mar 2006

Building A Consensus Forecast For Crude Oil Prices, Kenneth W. Burke

Theses and Dissertations

Skyrocketing fuel prices have stressed the Department of Defense's budget in recent years. In 2001 the DoD spent $4.7 Billion on fuel with the Air Force consuming $2.7 Billion. These figures have grown over due to these increases as well as the increased flying ours to support the Global War On Terror. In fact, the Fiscal Year 2007 budget has already been increased by $1.1 billion, or 1% of the total budget, to accommodate the increased price of fuel. Current forecasts of this resource have yielded poor results, impairing the DoD's ability to budget this critical expense. Further because the …

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Comparative Analysis Of Airborne Chemical Exposure To Air Force Small Arms Range Instructors, Eric J. Cameron Mar 2006

Comparative Analysis Of Airborne Chemical Exposure To Air Force Small Arms Range Instructors, Eric J. Cameron

Theses and Dissertations

This study examines airborne chemical exposure to Air Force small arms range instructors during M16 firing of lead and lead-free bullets. Historical range information collected from 63 active duty Air Force bases identified that two thirds of the Air Force military ranges within the Continental United States are currently firing lead-free ammunition. Average 8-hr TWA exposures for lead during M16 firing of leaded ammunition were 17% of the Occupational Exposure Limit (OEL). Task exposures, representing worst case conditions, were found to be 1.2 time the OEL. Two indoor and four outdoor firing ranges currently firing frangible lead-free ammunition were evaluated …

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A Market Reaction To Dod Contact Delay, Robert D. Carden Mar 2006

A Market Reaction To Dod Contact Delay, Robert D. Carden

Theses and Dissertations

Development projects are occurring at a faster rate in the civilian world than for the Department of Defense (DoD). In the civilian world, faster development means quicker delivery and sales. In the DoD, quicker product development equates to a more capable warfighter. On average, DoD Acquisition Category One (ACAT I) development projects are approaching a 15 year procurement cycle. In the last three years, acquisition cycle time has grown nearly 20 percent. It turns out that the very companies that have learned to be faster, leaner and more effective in their civilian endeavors do not seem to be functioning the …

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Hazardous Material Cargo Frustration At Military Aerial Ports Of Embarkation, Niel E. Christensen Mar 2006

Hazardous Material Cargo Frustration At Military Aerial Ports Of Embarkation, Niel E. Christensen

Theses and Dissertations

Since military units often require critical hazardous materials in an expedited manner, identifying choke points within the supply chain is necessary to improve logistic support to front line forces. Hazardous materials are some of the most critical assets for the war fighter, as well as the most restrictive and often most time consuming for transportation. This research quantifies the extent that vendor and depot supplied cargo is being delayed at Aerial Ports of Embarkation. By looking at frustrated hazardous material at Charleston Air Force Base, South Carolina and Dover Air Force Base, Delaware, a case study methodology is used to …

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Analysis Of Bacterial Population And Distribution In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Bioremediation, Milton J. Clausen Jr. Mar 2006

Analysis Of Bacterial Population And Distribution In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Bioremediation, Milton J. Clausen Jr.

Theses and Dissertations

Chlorinated hydrocarbons and their degradation products are among of the most common organic groundwater contaminates in the United States. These compounds attack the central nervous system in animals and can affect the photosynthesis of plants. These compounds are also resistant to degradation in the environment and, because of this, pose a risk to any ecosystem in which they are present. This study identified the dominant microbial species in a constructed treatment wetland at Wright-Patterson AFB, Dayton, Ohio using 16S rRNA gene sequence analysis. Samples were taken from three different depths and during each of the four seasons. These samples were …

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Contemplating A New Model For Air Force Aerospace Medical Technician Skills Sustainment Training, Robert M. Corrigan Mar 2006

Contemplating A New Model For Air Force Aerospace Medical Technician Skills Sustainment Training, Robert M. Corrigan

Theses and Dissertations

Two decades ago, Aerospace Medical Technicians received robust skills sustainment training through exposure to multifaceted patient treatment environments. Available training environments included inpatient care, outpatient care, and emergency services. This diverse training environment made possible through large operating budgets and an extraordinary infrastructure could not last. Today (after five separate base closure and realignment initiatives), medical funding and infrastructure is but a shadow of what it once was. Budget constraints and the rising cost of healthcare have necessitated a purposeful movement away from inpatient and emergency care, toward outpatient and preventative medicine. Although changes in Air Force health care delivery …

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In Vitro Toxicity Of Aluminum Nanoparticles In Rat Alveolar Macrophages, Andrew J. Wagner Mar 2006

In Vitro Toxicity Of Aluminum Nanoparticles In Rat Alveolar Macrophages, Andrew J. Wagner

Theses and Dissertations

Nanomaterials, which are by definition in the 1 - 100 nanometer range, have numerous possible benefits to society, but currently there is a lack of data that characterizes these materials effects on human health and environment. In general nanomaterials are of interest to the Air Force because of their applications in electronics, sensors, munitions and energetic/reactive systems. Nanoparticles such as aluminum have been considered for enhancing propulsion in solid rocket fuel. To date, only a few studies have looked at the toxicological effects of direct exposure to nanoparticles, none with aluminum. It is important to increase the understanding of the …

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An Asymmetrical Look At Air Force Human Capital Management: More Emphasis On Qualifications And Less On Rank, Daniel M. Romano Mar 2006

An Asymmetrical Look At Air Force Human Capital Management: More Emphasis On Qualifications And Less On Rank, Daniel M. Romano

Theses and Dissertations

This research explored an asymmetrical concept of personnel management, specifically whether status, rank, is an artificial barrier to employing qualified enlisted personnel in some company grade officer duties. It takes the approach under the Human Capital Theory and questions whether rank plays a roll in effective performance and whether eliminating rank as a criterion to employment, in some duties, can support Air Force transformation efforts, without negatively affecting culture (i.e. chain-of-command, customs and courtesies). It describes a concept where more emphasis is put on meeting the knowledge, education, experience, and training qualifications and the required rank be interchangeable between enlisted …

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Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii Mar 2006

Discrete Event Simulation Model Of The Ground Maintenance Operations Cycle Of A Reusable Launch Vehicle, John T. Pope Iii

Theses and Dissertations

The Air Force uses a family of expendable launch vehicles to meet its spacelift needs. Unfortunately, this method is not responsive: months of preparation are typically required and launch costs are high. Consequently, the Air Force seeks a reusable military launch vehicle that can be launched inexpensively and quickly regenerated between flights. Air Force Research Laboratory personnel desire a tool to help evaluate candidate designs and perform tradeoff studies necessary to acquire a launch vehicle that will achieve Air Force goals. The objective of this research was first to develop a conceptual model of maintenance operations needed to regenerate a …

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A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum Mar 2006

A Risk Assessment Methodology For Divesting Military Capabilities To Allied Nations, Jason A. Gastelum

Theses and Dissertations

The United States spent over $400 billion dollars on national defense in 2005. Even with support for the war on terrorism still strong, it is doubtful that the U.S. can sustain such a level of defense investment. One strategy to offset the increasing burden of defense spending is to divest the procurement and/or sustainment of individual defense capabilities to allied nations. The decision to divest any capability, however, introduces risk. This thesis presents a methodology to quantify the risk of the decision to divest a military capability to an allied nation, where risk is defined as the set of risk …

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Classification Characteristics Of Carbon Nanotube Polymer Composite Chemical Vapor Detectors, Huynh A. Hinshaw Mar 2006

Classification Characteristics Of Carbon Nanotube Polymer Composite Chemical Vapor Detectors, Huynh A. Hinshaw

Theses and Dissertations

The first step in combating a chemical weapons threat is contamination avoidance. This is accomplished by the detection and identification of chemical agents. The Air Force has several instruments to detect chemical vapors, but is always looking for lighter, faster, and more accurate technology for a better capability. This research is focused on using carbon nanotube polymer composite sensors for chemical detection. More specifically, models are developed to classify three sets of sensor data according to vapor using various multivariate techniques. Also, prediction models of a mixed sensor output are developed using neural networks and regression analysis. The classifiers developed …

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Analysis Of Patient Information: An Empirical Modeling Approach, Tony A. Murphy Mar 2006

Analysis Of Patient Information: An Empirical Modeling Approach, Tony A. Murphy

Theses and Dissertations

With rising costs and increasing complexities, many hospitals seek to better understand the intricate details of their operations. Increasingly, these organizations have a strong desire to accurately predict the resources required to effectively treat their patient load. This research investigates patient length-of-stay in a hospital neurological unit using an empirical modeling approach. Factors significantly affecting patient length of stay were identified and used to construct a regression model. The predictive model provides hospital decision makers with a compact tool to input what-if scenarios and predict future patient treatment lengths, thus, allowing the hospital to properly allocate resources.

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