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Air Force Institute of Technology

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Articles 211 - 240 of 421

Full-Text Articles in Civil and Environmental Engineering

Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz Aug 2010

Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz

Faculty Publications

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility …

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Development Of Measures To Assess Product Modularity And Reconfigurability, Amie C. Stryker Mar 2010

Development Of Measures To Assess Product Modularity And Reconfigurability, Amie C. Stryker

Theses and Dissertations

Several fundamental benefits of modularity are agreed upon by industry including reusability, flexibility, reconfigurability and extensibility. Interfaces within or between modules which establish provide/depend relationships are the focus of current modularity measures. This research outlines a new method and measures for assessing product modularity in terms of degree of coupling and the recognized modularity benefits. A five–step analysis process is developed and used to guide the modularity assessment. Defining and decomposing products are performed first. Using the resultant functional model from the first step, the identified functions are mapped to modules in a product in the second step. In the …

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Cca: Exploratory Case Study Of Construction In A Contingency Environment, Michael J. Pluger Mar 2010

Cca: Exploratory Case Study Of Construction In A Contingency Environment, Michael J. Pluger

Theses and Dissertations

Top military leadership has identified problems with the timeliness and effectiveness of DoD contingency construction support. Qualitative data was collected in order to gain clarity on the problem space and lay a foundation for solution generation and selection. Interviews were conducted with agents with experience within the Iraq and Afghanistan theater of operation as well as support functions for the Pentagon. Commanders, Engineers, Lawyers, Acquisition Attorneys, Staff Officers and Program Managers have been interviewed. The interviews have been analyzed using open coding to answer research question and identify to emergent themes and concepts. The data collected has revealed that Contingency …

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Manpower Cost Analysis Of A Distributed En Route Support Structure Versus A Consolidated En Route Support Structure, Phillip M. Rehmert Mar 2010

Manpower Cost Analysis Of A Distributed En Route Support Structure Versus A Consolidated En Route Support Structure, Phillip M. Rehmert

Theses and Dissertations

The United States military has developed an en route support structure for airlift requirements to deploy and sustain combat forces in conflict. The Air Mobility Command (AMC) is interested in determining the cost effectiveness of two distinctly different en route structures, in particular, the cost effectiveness of one large facility versus supporting combat forces with many smaller facilities. With the current operational tempo, continued analysis must be accomplished to determine if a smaller footprint is possible in the deployment and sustainment scenarios of conflicts seen today; conflicts more centered on a leaner and faster deployment force. This research examines the …

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Knowledge Transformation In The United States Air Force Civil Engineer Career Field: A System Dynamics Approach, Gregory J. Ward Mar 2010

Knowledge Transformation In The United States Air Force Civil Engineer Career Field: A System Dynamics Approach, Gregory J. Ward

Theses and Dissertations

Recent operations in Iraq and Afghanistan have brought the level of expeditionary contractors to historically unprecedented levels, altering the work composition for military engineers. The alteration has shifted emphasis from technical knowledge areas toward managerial knowledge associated with supervising the increased number of contractors. This research utilizes System Dynamics modeling to analyze this shift in the United States Air Force Civil Engineer officer career field and resulting transformative effect on career field knowledge levels, both technical and managerial. The model is then tested with multiple external policy adjustments in the areas of career field structure, training, and operating policy. Results …

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Analysis And Modeling Of Motor Vehicle Crashes Involving Air Force Military Personnel, Antonios Markopoulos Sep 2009

Analysis And Modeling Of Motor Vehicle Crashes Involving Air Force Military Personnel, Antonios Markopoulos

Theses and Dissertations

The primary purpose of this thesis was to improve the data analysis of Motor Vehicle Crashes (MVCs). This thesis employed the Air Force Safety Center (AFSC) data, collected over 20 years, of MVCs in which US Air Force (USAF) military personnel are involved when off duty and off base. Categorical Data Analysis and Analysis of Variance (ANOVA) were applied to identify risk factors related to MVCs and influence the severity of injuries and those factors associated with the alcohol consumption before driving, and affect the number of lost workdays resulting from MVCs. Categorical Data Analysis showed that male USAF members …

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Ground Source Heat Pumps Vs. Conventional Hvac: A Comparison Of Economic And Environmental Costs, Paul W. Fredin Mar 2009

Ground Source Heat Pumps Vs. Conventional Hvac: A Comparison Of Economic And Environmental Costs, Paul W. Fredin

Theses and Dissertations

The world is undergoing a dramatic transformation with regard to how it produces and consumes energy due to increasing demand from developing nations and diminishing new resource discoveries. In addition, there has been increased concern over the effect of carbon dioxide emissions on the environment. All of these issues have created a combined pressure to force the world to begin to redefine how energy is utilized. Geothermal or ground source heat pumps (GSHPs) may provide one potential solution to these problems. This research investigated vertical borehole closed-loop GSHP systems in direct comparison to natural gas furnaces combined with traditional air-conditioning …

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An Economic Analysis Of Military Family Housing: Should The Government Continue To Privatize?, Chad A. Woods Mar 2009

An Economic Analysis Of Military Family Housing: Should The Government Continue To Privatize?, Chad A. Woods

Theses and Dissertations

Providing military family housing has always been a difficult task for the United States government. To solve the latest housing short fall, the government signed the Military Housing Privatization Initiative (MHPI) into law in 1996. Under this program the government contracts private developers to build, own, and operate housing units. The developer then collects rent through housing allowance payments. At the time MHPI was signed into law, military members were expected to pay 15 percent of their housing costs out of pocket. Subsequent legislation has increased housing allowance to provide 100 percent of all housing costs eliminating out of pocket …

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A Cost Assessment Of The Dayton Public Schools Vehicle Routing Problem, Frankie L. Woods Jr. Mar 2009

A Cost Assessment Of The Dayton Public Schools Vehicle Routing Problem, Frankie L. Woods Jr.

Theses and Dissertations

The routing and scheduling problem involves both constructing efficient routes to deliver goods or services to and from customers from a single depot or set of depots, as well as scheduling particular vehicles to these routes such that customers receive their goods within a specified time window. There have been several different methods developed to reduce the costs incurred in transporting goods or services (i.e. students) to customers (i.e. schools). This problem may be used to model many circumstances in logistics and public transportation. Several school districts do not utilize operations research techniques to minimize, as much as possible, the …

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An Analysis Of Construction Contractor Performance Evaluation System, Rebecca S. Brown Mar 2009

An Analysis Of Construction Contractor Performance Evaluation System, Rebecca S. Brown

Theses and Dissertations

A rigorous system for rating construction contractor performance does not exist for the USAF as identified by the Air Force Civil Engineer (USAF CE), Major General Del Eulberg (Eulberg, 2007). The United States Army Corp of Engineers (USACE) uses DD Form 2626 for contractor performance evaluation and contractor selection. The objective of this research is to strengthen the USAF contractor rating system by exploring USACE‘s use of DD Form 2626. Using data from DD Form 2626, statistical analysis was conducted to determine if the measured performance sub-items reflect their respective performance elements, whether the resulting performance elements relate to the …

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Ohio River Denial As A Transportation Corridor And Its Economic Impacts On The Energy Industry, Caglar Utku Guler Mar 2009

Ohio River Denial As A Transportation Corridor And Its Economic Impacts On The Energy Industry, Caglar Utku Guler

Theses and Dissertations

What if the Ohio River is disrupted or denied partially or completely as a transportation corridor? A disruption may be either a natural or man-made disaster or a planned outage on the river’s lock and dam structures. Recent history is full of water transport disruption events having significant economic effects on the waterside industries. To assess coal-based economic impacts, we developed a network flow model to represent waterside coal-fired power plants situated along the Ohio River, their respective coal supplying mines, and the various transportation modes that connect them. We show that significant transportation-centric insights can be derived by using …

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Development Of A Screening Tool To Facilitate Technology Of An Innovative Technology To Treat Perchlorate-Contaminated Water, Daniel A. Craig Mar 2008

Development Of A Screening Tool To Facilitate Technology Of An Innovative Technology To Treat Perchlorate-Contaminated Water, Daniel A. Craig

Theses and Dissertations

Perchlorate contamination of drinking water is a significant problem nationwide. The purpose of this study was to develop a tool to predict the cost and performance of tailored granular activated carbon (T-GAC), an innovative technology that is being evaluated as a cost-effective treatment for perchlorate-contaminated water. The ability to accurately predict performance and cost can facilitate the transfer and commercialization of innovative technologies. In the study, a model was developed to predict T-GAC performance and life-cycle costs for removing perchlorate under varying influent water quality and technology operating conditions. The model's design parameters were obtained from laboratory rapid small-scale column …

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Selecting The Best Thermal Building Insulation Using A Multi-Attribute Decision Model, Theodore J. Sotoropolis Mar 2008

Selecting The Best Thermal Building Insulation Using A Multi-Attribute Decision Model, Theodore J. Sotoropolis

Theses and Dissertations

Thermal building insulation has traditionally been viewed as a means to reduce thermal conductivity through the building envelope. Builders typically choose the least expensive material which meets the specifications in order to remain competitive. Other factors regarding long term health and environmental consequences are typically dismissed. However, a recent shift toward sustainability requires that architects and engineers take a more responsible approach to building design. This research takes a holistic approach to selecting thermal building insulation through the use of a multi-attribute decision model. Several types of insulating products from a variety of manufacturers were investigated in order to determine …

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Factors Leading To Effectiveness And Satisfaction In Civil Engineer Information Systems, Donald C. Crabtree Mar 2008

Factors Leading To Effectiveness And Satisfaction In Civil Engineer Information Systems, Donald C. Crabtree

Theses and Dissertations

The Air Force Civil Engineer Support Agency (AFCESA) has developed information systems in support of civil engineer operations. Over the last decade, the number of systems has grown to support the breadth of civil engineer functions. At this time, numerous (900+) decentralized systems support civil engineer functions around the world. Due to budget constraints, AFCESA is transforming civil engineer business processes to leverage the workforce in an optimized fashion. In support of this transition, AFCESA is posturing to acquire new information systems in support of civil engineer business processes. To help AFCESA improve upon its suite of information systems development …

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An Analysis Of Construction Cost And Schedule Performance, Michael J. Beach Mar 2008

An Analysis Of Construction Cost And Schedule Performance, Michael J. Beach

Theses and Dissertations

Cost and schedule performance are widely accepted in the literature and in industry as effective measures of the success of the project management effort expended. Earned Value Analysis (EVA) offers many metrics to objectively measure cost and schedule performance of many different types of projects. The author utilized EVA to objectively measure the cost and schedule performance of completed United States Air Force (AF) Military Construction (MILCON projects from 1990 to 2005. The impact of Major Command (MAJCOM), Construction Agent (CA), and facility type (CATCODE) and the combination of these variables on the EVA metrics of Cost Performance Index (CPI), …

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Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger Mar 2008

Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger

Theses and Dissertations

Environmental managers utilize a variety of tools when assessing lotic systems for stressors attributed to anthropogenic sources. Stream deposited sediment has been recognized as one of the major stressors affecting streams in the U.S. The detrimental effect on aquatic biota of sediment depositing within the interstitial spaces of stream substrate (embeddedness) has been established, yet lacking is an effective in situ method of quantifying embeddedness over short time periods. The goal of this research was to develop a short-term embeddedness (EMB) quantification method that can be linked to benthic macroinvertebrate health. Such a method would be a valuable tool when …

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Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon Mar 2008

Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon

Theses and Dissertations

16S rRNA gene analysis was performed on soil samples from a subsurface flow mesocosm experiment, mimicking a constructed wetland. Three typical wetland species of plant were used in nine of the columns and three columns were unplanted controls. Analyses showed that plant presence, plant species, and depth did not have a significant effect on microbial community composition. However, richness analyses illustrated that plant presence had a positive effect on richness, plant species analyses indicated that there was evidence that plant species affected richness in a significant manner, and lastly richness was negatively affected in the bottom depth for the control …

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Rapid Runway Repair (Rrr): An Optimization For Minimum Operating Strip (Mos) Selection, David J. Duncan Mar 2007

Rapid Runway Repair (Rrr): An Optimization For Minimum Operating Strip (Mos) Selection, David J. Duncan

Theses and Dissertations

Minimum Operating Strip (MOS) selection determines the exact placement of the MOS on the damaged runway, and therefore, the amount of munitions that need to be neutralized and the amount of damage that will need to be repaired. MOS selection, in essence, is the key determinant of the time required to attain an operational takeoff and recovery surface. Since the MOS selection stage determines the events and scope of work for all of the Rapid Runway Repair (RRR) stages that follow, it could be argued that this is the most important stage in the entire RRR process. The primary purpose …

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Decision Analysis With Value Focused Thinking As A Methodology To Select Building For Deconstruction, Erika E. Maiorano Mar 2007

Decision Analysis With Value Focused Thinking As A Methodology To Select Building For Deconstruction, Erika E. Maiorano

Theses and Dissertations

The purpose of this research was to examine the reuse and recycling of building materials on Wright-Patterson Air Force Base. There are a variety of conflicting factors concerning the removal of a building and the model quantitatively evaluates alternatives with respect to the decision maker’s values. The research questions were addressed with both a comprehensive literature review as well as the implementation of the value focused thinking methodology. The model found that the temporary living facilities are the alternatives that achieve the highest value. The result of this research effort was a value model that aids decision makers in identifying …

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Modeling In Situ Bioremediation Of Perchlorate-Contaminated Groundwater, Roland E. Secody Mar 2007

Modeling In Situ Bioremediation Of Perchlorate-Contaminated Groundwater, Roland E. Secody

Theses and Dissertations

Perchlorate-contaminated groundwater is a significant problem for the Department of Defense and the United States Air Force. An innovative technology was recently developed which uses dual-screened treatment wells to mix an electron donor into perchlorate-contaminated groundwater in order to effect in situ bioremediation of the perchlorate by indigenous perchlorate reducing bacteria without the need to extract the contaminated water from the subsurface. In this study, a model that simulates operation of the technology is calibrated and validated using 761 days of observational data obtained from a field-scale technology evaluation project. A genetic algorithm was used with the first 113 days …

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Biofiltration As A Viable Alternative For Air Pollution Control At Department Of Defense Surface Coating Facilities, David M. Hudock Mar 2007

Biofiltration As A Viable Alternative For Air Pollution Control At Department Of Defense Surface Coating Facilities, David M. Hudock

Theses and Dissertations

Surface coating operations at aircraft depot facilities are common throughout the Department of Defense (DoD). During paint application processes at Navy and Marine Corps Fleet Readiness Centers (FRCs), spray paints emit volatile organic compounds (VOCs) known to have harmful effects on human health and the environment. FRC East at Marine Corps Air Station Cherry Point, does not control the emissions of VOCs from any of its paint booths. The purpose of this research is to determine if FRC East and its surrounding area can benefit both economically and environmentally from a biofiltration system for air pollution control (APC) rather than …

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Development Of A Screening Model For Design And Costing Of An Innovative Tailored Granular Activated Carbon Technology To Treat Perchlorate-Contaminated Water, William C. Powell Mar 2007

Development Of A Screening Model For Design And Costing Of An Innovative Tailored Granular Activated Carbon Technology To Treat Perchlorate-Contaminated Water, William C. Powell

Theses and Dissertations

Perchlorate contamination of drinking water is a problem that has recently gained national attention. The purpose of this research was to develop a tool to predict the cost and performance of tailored granular activated carbon (T-GAC), an innovative technology to treat perchlorate-contaminated water. The ability to predict cost and performance is essential to promote transfer and commercialization of innovative technologies. This study investigated how data obtained from small-scale laboratory tests could be applied to predict cost and performance of a full-scale T-GAC system to treat perchlorate-contaminated water. A technology model was developed using GAC design principles and using a multi-component …

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The Effects Of Orthophosphate As A Copper Corrosion Control Inhibitor In High Alkalinity Drinking Water Systems, Stephen Grace Mar 2007

The Effects Of Orthophosphate As A Copper Corrosion Control Inhibitor In High Alkalinity Drinking Water Systems, Stephen Grace

Theses and Dissertations

The purpose of this research was to investigate orthophosphate as a corrosion inhibitor for copper pipe in a high-alkalinity drinking water system. Specifically, this thesis sought to answer three research questions regarding the impact of orthophosphate treatment, the nature of the mechanism by which orthophosphate controls copper corrosion, and the value of equilibrium modeling in predicting orthophosphate’s effects. The research questions were answered through a comprehensive literature review and experimental methodology integrating laboratory jar tests, water sampling and analysis from a field investigation, qualitative solids analysis, and equilibrium model application. This study analyzed field data obtained over the course of …

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Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron Mar 2007

Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron

Theses and Dissertations

Chlorinated solvents, including perchloroethene (PCE) and trichlorethene (TCE), are among the most common groundwater contaminants found in the United States. Once released into the environment, chlorinated solvents are extremely persistent and often require costly and lengthy remedial actions. The use of constructed wetlands has shown promise as an effective and less costly alternative for the treatment of chlorinated solvent contaminated groundwater. This study characterized and evaluated the concentration of chlorinated ethenes within a vertical flow constructed wetland, fed with PCE contaminated groundwater, at Wright-Patterson Air Force Base (WPAFB), Ohio. Chlorinated ethene concentrations were characterized within three distinct layers of the …

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A Decision Model For Selecting Energy Efficient Technologies For Low -Sloping Roof Tops Using Value-Focused Thinking, Michael J. Mccourt Mar 2007

A Decision Model For Selecting Energy Efficient Technologies For Low -Sloping Roof Tops Using Value-Focused Thinking, Michael J. Mccourt

Theses and Dissertations

The Air Force has a large inventory of low-sloping built up roofs (BURs) and millions of dollars are spent each year retrofitting these systems. The DOD has been directed to reduce non-renewable energy consumption by using energy-efficient technologies. These two details present a great opportunity to use the open roof space to install energy-efficient roofing technologies. The purpose of this research is to provide Air Force decision makers with a tool to assist them in deciding what roofing technologies should be installed on facilities. Value Focused-Thinking is the methodology used to construct the model, in which values were used, instead …

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A Value-Focused Thinking Model For The Selection Of The Best Rigid Pavement, Partial-Depth Spall Repair Material, Benjamin G. Speer Mar 2007

A Value-Focused Thinking Model For The Selection Of The Best Rigid Pavement, Partial-Depth Spall Repair Material, Benjamin G. Speer

Theses and Dissertations

Concrete spalls on airfield pavements generate foreign object debris (FOD) that is damaging to aircraft engines, and may damage landing gear by roughening of the pavement surface. Repairing spalled concrete on aging and deteriorating airfields is essential for its safe operational use. Picking the best repair material from many products on the commercial market is difficult. There is wide variation on material properties, and good performance on certain criteria is critical to constructing long lasting repairs. Since there is currently no procedure for Air Force decision-makers to select the best rigid-pavement repair material, a model was created using Value-Focused Thinking …

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Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone Mar 2007

Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone

Theses and Dissertations

Stormwater runoff occurs naturally after every storm event; however, traditional development practices have created many impervious surfaces, such as buildings, parking lots, and streets that increase runoff volume and flow rate. Conventional stormwater management practices focus on collecting runoff into centralized channels and conveying it as quickly as possible to local bodies of water. This type of conveyance system decreases the opportunity for stormwater to naturally infiltrate back into the ground. It also prevents contaminants from being naturally filtered out of stormwater flows. As a result, centralized conveyance systems can cause flooding, erosion, and terrestrial and aquatic habitat degradation. Innovative …

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Evaluation Of Microbial Diversity In Wetland Through Polymerase Chain Reaction (Pcr) And Restriction Fragment Length Polymorphism (Rflp), Gregory K. Joseph Jun 2006

Evaluation Of Microbial Diversity In Wetland Through Polymerase Chain Reaction (Pcr) And Restriction Fragment Length Polymorphism (Rflp), Gregory K. Joseph

Theses and Dissertations

The diversity of microbial communities in wetlands has not been fully measured. These communities may offer tools to naturally remediate sites polluted with chlorinated compounds. Polmerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) are genomic techniques that are capable of rapidly characterizing bacteria communities and can provide valuable information about the diversity of microbial communities.

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Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop Jun 2006

Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop

Theses and Dissertations

The use of wetlands to effectively remediate aquifers contaminated with chlorinated solvents is an emerging technique, which shows high promise. In order to better understand this process and test its legitimacy, a treatment wetland was constructed at Wright-Patterson AFB, Dayton, Ohio and, in a joint effort with Wright State University (WSU), has previously shown the effective removal of PCE. The purpose of this research was to characterize the soil bacterial community, pre-PCE injection, among three wetland plant species from the sedge family (Cyperaceae) within constructed wetland mesocosms and to identify any bacterial dominance. Carex comosa, Scirpus atrovirens, and Eleocharis erythropoda …

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Risk-Based Decision Model For Determining The Applicability Of An Earned Value Management System In Construction, Mark D. Workman Mar 2006

Risk-Based Decision Model For Determining The Applicability Of An Earned Value Management System In Construction, Mark D. Workman

Theses and Dissertations

New policy mandated by the Undersecretary of Defense for Acquisition, Technology and Logistics has lowered the dollar thresholds of contracts requiring earned value management (EVM). This policy directed that a "risk-based decision" be made to determine if EVM should be used on firm-fixed price contracts under $20 million. Although not previously applicable to Military Construction (MILCON) building projects or other Air Force Civil Engineer (CE) managed contracts, the new threshold requires that CE projects be evaluated for risk. Therefore, the focus of this research was to analyze the risk factors associated with construction contracts in an attempt to build a …

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