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Turnover Intentions: A Quantitative Analysis Of Comments From Air Force Civil Engineering Company Grade Officers, TJ E. Gabrielson 2012 Air Force Institute of Technology

Turnover Intentions: A Quantitative Analysis Of Comments From Air Force Civil Engineering Company Grade Officers, Tj E. Gabrielson

Theses and Dissertations

Voluntary turnover is a concern for the military and many other organizations from a financial and performance standpoint. This study applied grounded theory to code and network comments provided by CE officers in 2010. The results of this study found the most influential construct that predicts turnover intentions to be the relationship of OPSTEMPO influencing interrole conflict. This conflict is increased by the workload at home station due to under manning within CE. OPSTEMPO is an important aspect of a military member's decision to stay or leave the service because it was found to interact with a multitude of other …


Asset Management: Roof Maintenance And Facility Energy Retrofits, Joseph P. DiRosario 2012 Air Force Institute of Technology

Asset Management: Roof Maintenance And Facility Energy Retrofits, Joseph P. Dirosario

Theses and Dissertations

The United States Air Force (USAF) needs aggressive new techniques to compliment its asset management of its real estate portfolio. Air Force officials are experiencing budget cuts that have led to degraded facility infrastructure. Two areas of operations in which there are opportunities to improve the asset management of Air Force facilities are roof maintenance and energy retrofits. Information obtained via a geospatial information systems analysis revealed that the current state of the rooftop maintenance program was deficient and supported strategic sourcing as a potential solution to the program's deficiencies. In addition, two methodologies were created to gauge the effectiveness …


Understanding The Impact Of Bead Type On Paint And Thermoplastic Pavement Markings, Joshua D. Hollingsworth 2012 Air Force Institute of Technology

Understanding The Impact Of Bead Type On Paint And Thermoplastic Pavement Markings, Joshua D. Hollingsworth

Theses and Dissertations

Each year the United States spends approximately two billion dollars maintaining pavement markings. In addition, an impending Federal policy establishing a minimum retro-reflectivity value for pavement markings has driven asset managers to develop performance models to effectively and efficiently manage these high quantity, low cost assets. Research over the past decade has sought to identify and understand the many factors influencing pavement marking degradation. Despite the fact that reflective glass beads are foundational to pavement marking retro-reflectivity, little research has specifically considered the impacts of bead type. The purpose of this study is to quantify the impact that bead type …


Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard 2012 University of South Florida

Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard

USF Tampa Graduate Theses and Dissertations

Self supply is an emerging approach to water supply which focuses on fostering household investment in incremental improvements to their water sources. When successful, it can lower costs and increase sustainability by offering users a larger share

of ownership in their own supply, and harnessing the already existing strengths of a community rather than trying to impose an external perspective. In addition to well upgrading and source protection, one of the key self supply areas is rainwater harvesting.

Uganda has a diverse selection of rainwater storage options, but many of them are scattered and disparate.

The objective of this study …


Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks 2012 University of South Florida

Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks

USF Tampa Graduate Theses and Dissertations

In recent years, much focus has been put on the sustainability of water and sanitation development projects. Experts in this field have found that many of the projects of the past have failed to achieve sustainability because of a lack of demand for water and sanitation interventions at a grassroots level. For years projects looked to create this demand through various subsidy schemes, with the "software" of behavior change and education taking a backseat to the "hardware" of infrastructure provision. Community-Led Total Sanitation (CLTS) is a fairly new way of looking at the issues of increasing basic sanitation coverage, promoting …


Time-Weighted Average Spme Analysis For In Planta Determination Of Cvocs, Emily M. Sheehan, Matt A. Limmer, Philipp Mayer, Ulrich Gosewinkel Karlson, Joel Gerard Burken 2012 Missouri University of Science and Technology

Time-Weighted Average Spme Analysis For In Planta Determination Of Cvocs, Emily M. Sheehan, Matt A. Limmer, Philipp Mayer, Ulrich Gosewinkel Karlson, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Potential of Phytoscreening for Plume Delineation at Contaminated Sites Has Promoted Interest in Innovative, Sensitive Contaminant Sampling Techniques. Solid-Phase Microextraction (SPME) Methods Have Been Developed, Offering Quick, Undemanding, Noninvasive Sampling Without the Use of Solvents. in This Study, Time-Weighted Average SPME (TWA-SPME) Sampling Was Evaluated for in Planta Quantification of Chlorinated Solvents. TWA-SPME Was Found to Have Increased Sensitivity over Headspace and Equilibrium SPME Sampling. using a Variety of Chlorinated Solvents and a Polydimethylsiloxane/carboxen (PDMS/CAR) SPME Fiber, Most Compounds Exhibited Near Linear or Linear Uptake over the Sampling Period. Smaller, Less Hydrophobic Compounds Exhibited More Nonlinearity Than Larger, More …


Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh 2012 University of South Florida

Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh

USF Tampa Graduate Theses and Dissertations

While understanding the kinetics of algae growth plays an important role in improving algae cultivation technology, none of the existing kinetic models are able to describe algae growth when more than three growth limiting factors are involved. A model was developed in this study to describe algae growth in a photobioreactor. Two expressions were proposed based on the Monod model to relate the specific growth rate of algae to the concentration of nitrogen, phosphorus, inorganic carbon and light intensity in the culture media. Algal biomass concentration as a function of time was calculated by solving mass and energy balances around …


Life-Cycle Cost Analysis Of Alternative Reinforcement Materials For Bridge Superstructures Considering Cost And Maintenance Uncertainties, Christopher D. Eamon, Elin A. Jensen, Nabil F. Grace, Xiuwei Shi 2012 Wayne State University, Detroit, MI

Life-Cycle Cost Analysis Of Alternative Reinforcement Materials For Bridge Superstructures Considering Cost And Maintenance Uncertainties, Christopher D. Eamon, Elin A. Jensen, Nabil F. Grace, Xiuwei Shi

Civil and Environmental Engineering Faculty Research Publications

A life cycle cost analysis (LCCA) was conducted on prestressed concrete bridges using carbon fiber reinforced polymer (CFRP) bars and strands. Traditional reinforcement materials of uncoated steel with cathodic protection and epoxy-coated steel were also considered for comparison. A series of deterministic LCCAs were first conducted to identify a range of expected cost outcomes for different bridge spans and traffic volumes. Then, a probabilistic LCCA was conducted on selected structures that included activity timing and cost random variables. It was found that although more expensive initially, the use of CFRP reinforcement has the potential to achieve significant reductions in life …


Damage Tolerance Of Unidirectional Carbon And Fiberglass Composites With Aramid Sleeves, Charles Andrew Sika 2012 Brigham Young University - Provo

Damage Tolerance Of Unidirectional Carbon And Fiberglass Composites With Aramid Sleeves, Charles Andrew Sika

Theses and Dissertations

Unidirectional carbon fiber and fiberglass epoxy composite elements consolidated with aramid sleeves were radially impacted at 5 J (3.7 ft-lbs) and 10 J (7.4 ft-lbs), tested under compression, and compared to undamaged control specimens. These structural elements represent local members of open three-dimensional composite lattice structures (e.g., based on isogrid or IsoTruss® technologies). Advanced three-dimensional braiding techniques were used to continuously fabricate these specimens. The unidirectional core specimens, 8 mm (5/16 in) in diameter, were manufactured with various sleeve patterns. Bi-directional braided sleeves and unidirectional spiral sleeves ranged from a nominal full to half coverage. These specimens were tested for …


Evaluating Climate Change Effects In Two Contrasting Reservoirs Using Two-Dimensional Water Quality And Hydrodynamic Models, Oliver Obregon 2012 Brigham Young University - Provo

Evaluating Climate Change Effects In Two Contrasting Reservoirs Using Two-Dimensional Water Quality And Hydrodynamic Models, Oliver Obregon

Theses and Dissertations

I analyzed and compared impacts from global climate change (GCC) and land use change to Deer Creek (United States) a temperate reservoir and Aguamilpa (Mexico), a tropical reservoir by using calibrated CE-QUAL-W2 (W2) water quality and hydrodynamic models based on field data over an extended time period. I evaluated and compared the sensitivity to predicted GCC and land use changes. I individually evaluated changes to air temperature (TAIR), inflow rates (Q), and nutrient loads (PO4-P and NO3-NO2-N) followed by analysis of worst case scenarios. I developed analysis methods using indexes to represent the total …


Study Of Water Quality Of Utah Lake Tributaries And The Jordan River Outlet For The Calibration Of The Utah Lake Water Salinity Model (Lksim), Gordon Killarney Liljenquist 2012 Brigham Young University - Provo

Study Of Water Quality Of Utah Lake Tributaries And The Jordan River Outlet For The Calibration Of The Utah Lake Water Salinity Model (Lksim), Gordon Killarney Liljenquist

Theses and Dissertations

The water quality of Utah Lake is of great importance to agriculture, recreation, and wildlife. The Utah Lake Simulation Model (LKSIM) was created to accurately predict changes in water quality parameters. However, a potential limitation of LKSIM is the age of the underlying data which was gathered from 1930 to 1980. New sample data were collected from March 2009 through May 2011. Samples were taken from 13 tributaries, the Jordan River Outlet, and various wastewater treatment plants (WWTP). Upon dividing the collected data points into seasons and plotting them in Microsoft Excel, trendline equations were produced. These equations correlated TDS …


Losing The Lake: Development And Deployment Of An Educational Game, Joseph M. Vesco, Katie Gilgen, Anne Paine, Marissa Owens, Michael Nussbaum, Gale M. Sinatra, Sajjad Ahmad, Kent J. Crippen, Sergiu Dascalu, Frederick C. Harris 2012 University of Nevada, Reno

Losing The Lake: Development And Deployment Of An Educational Game, Joseph M. Vesco, Katie Gilgen, Anne Paine, Marissa Owens, Michael Nussbaum, Gale M. Sinatra, Sajjad Ahmad, Kent J. Crippen, Sergiu Dascalu, Frederick C. Harris

Civil and Environmental Engineering and Construction Faculty Research

When asked what the top three issues of the Las Vegas region were, the reply was “water, water, water!" This was the result of a survey done a few years ago of Las Vegas Valley TV anchors. The reason for this response is that sustainability of the urban environments requires sufficient water resources as does population growth. With the advent of global climate change, this resource is in danger. Water flow and mountainous ice packs are impacted by this change in climate there by impacting the amount of water the the region. This is compounded over time as the population …


Civil Engineering And Construction News, Georgia Southern University 2012 Georgia Southern University

Civil Engineering And Construction News, Georgia Southern University

Civil Engineering & Construction News (2011-2022)

  • New Allen E. Paulson College of Engineering and Information Technology Announced


Maintenance Operations Degradation Of Airfield Pavement Markings, John C. Jaszkowiak 2012 Air Force Institute of Technology

Maintenance Operations Degradation Of Airfield Pavement Markings, John C. Jaszkowiak

Theses and Dissertations

Pavement markings are an essential element in the navigational aids subsystem for any airfield. Most airfields still use waterborne paint as the primary marking material, although there are other materials in use on roadways that airfield managers could use to save time and money. An airfield experiences a host of maintenance operations that cause degradation of the pavement markings. Of particular concern are rubber removal operations, sweeping operations, and snowplowing operations. This research focuses on chemical rubber removal operations and sweeping operations. The study evaluates waterborne paint markings and thermoplastic marking strips to determine if these marking materials perform differently …


Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser 2012 University of South Florida

Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser

USF Tampa Graduate Theses and Dissertations

It is estimated that only one percent of global freshwater is available to humans, with nearly three billion people living in water scarce conditions. Populations living in impoverished settings are particularly vulnerable to water related illnesses, with approximately 2.2 million people dying each year from to waterborne illnesses. This research uses modeling and field studies to assess the quantity, quality, and economics of distillate produced for drinking water from a brackish water source using two single-sloped, single-basin distillation reactors. The reactors were constructed from adobe and concrete in an arid rural community in San Luis Potosí, Mexico and tested from …


Characterization And Pollutant Loading Estimation For Highway Runoff In Omaha, Nebraska, Camilo Torres 2012 University of Nebraska-Lincoln

Characterization And Pollutant Loading Estimation For Highway Runoff In Omaha, Nebraska, Camilo Torres

Camilo Torres

Stormwater from roadways could have negative effects on the environment. Typical highway runoff pollutants include heavy metals, petroleum hydrocarbons, gasoline constituents, PAHs (polyaromatic hydrocarbons), oxygen demanding compounds measured as COD (chemical oxygen demand) and BOD (biochemical oxygen demand), and road salts. The objectives of this research were: characterize the pollutants in roadway runoff and determine the effectiveness of the existing stormwater BMPs at the study site. To accomplish these objectives, eleven rainfall events were sampled from November 2008 through November 2010. First flush and composite highway runoff samples were analyzed for heavy metals, anions, nutrients, particulates, BOD, COD, VOCs, and …


Evaluation Of Toxicity Analysis For Foundry Sand Specifications, M. Katherine Banks, A. Paul Schwab 2012 Purdue University

Evaluation Of Toxicity Analysis For Foundry Sand Specifications, M. Katherine Banks, A. Paul Schwab

Arthur Paul Schwab

Byproducts from many industries have the potential to be used as construction materials, but some means is required to determine if the material is environmentally benign. Foundry sands are produced in many states and can be useful as in transportation projects. However, INDOT currently requires the use of the MICROTOX test to assess the potential toxicity of the sands, and this requirement is viewed as an unnecessary impediment by the producers of foundry sands and is a requirement not encountered in other states. Therefore, the goal of this project was to review current requirements for testing of recycled materials, determine …


Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais 2012 University of Massachusetts Amherst

Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais

Mary Dehais

Nonpoint source (NPS) pollution is one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices that include bioretention. The two most common …


Estimating Dilemma Zone Hazard Function At High Speed Isolated Intersection, Anuj Sharma, Darcy Bullock, Srinivas Peeta 2012 University of Nebraska at Lincoln

Estimating Dilemma Zone Hazard Function At High Speed Isolated Intersection, Anuj Sharma, Darcy Bullock, Srinivas Peeta

Darcy M Bullock

The traditional surrogate measures of safety (like number of vehicles in dilemma zone) fail to quantify the risk of crash. Traffic conflict has been proposed as an improved surrogate measure of safety for operations at isolated intersections to quantify the risk. This paper develops a dilemma zone hazard function estimating procedure to obtain the probability of traffic conflict occurring. This approach is an extension of the current approach of dilemma zone boundaries to determine the risk of traffic conflict for an individual vehicle in the case of a dilemma zone incursion. Field data collected from the intersection of SR37 and …


Evaluation Of Stop Bar Video Detection Accuracy At Signalized Intersections, Avery Rhodes, Darcy M. Bullock, James R. Sturdevant, Zachary Thomas Clark 2012 Kittelson & Associates, Inc.

Evaluation Of Stop Bar Video Detection Accuracy At Signalized Intersections, Avery Rhodes, Darcy M. Bullock, James R. Sturdevant, Zachary Thomas Clark

Darcy M Bullock

Many agencies nationwide have adopted video vehicle detection technology as an alternative to inductive loops. While many product evaluations have been performed, the majority of these evaluations have concentrated on freeway applications where speed and volume were the primary evaluation criteria. At an actuated intersection, the metrics of speed and volume do not necessarily represent how well a device will operate as a presence detector. Video detection was evaluated at two signalized intersections in West Lafayette, Indiana and Noblesville, Indiana. A camera on each approach was located at the vendor recommended position, at a height of 40 feet and offset …


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