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Full-Text Articles in Engineering

Risks Associated With Federal Construction Projects, Krishna R. Surajbally Jun 2011

Risks Associated With Federal Construction Projects, Krishna R. Surajbally

Theses and Dissertations

The rise in terrorism, corporate espionage, cyber attacks, and federal fiscal constraints play an important role in the federal construction process. The risks associated with these occurrences are studied to aid in the risk management of the military construction process. This paper presents the status of research into these areas to identify how methods, policies, applications, and information obtained from case studies can be used by stakeholders to manage risk in the United States Air Force construction process. The author reviewed research on risk associated with four essential components of the military construction process – Critical Infrastructure, Information Technology, Contracts, …


Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim Mar 2011

Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim

Theses and Dissertations

Nanomaterials, classified as materials within the 1 - 100 nanometer range, have seemingly endless applications. It is very important to the Air Force to increase the understanding of Cu-NPs and the possible health impacts from nanomaterial exposure prior to wide-spread industry and military use. Therefore, the purpose of this research is to thoroughly characterize the properties of three different copper samples upon suspension into aqueous solutions over time: Cu-NPs (Cu 25 nm), CuO-NPs (CuO 40 nm), and Cu-MSP (Cu 500nm). Additionally, this research seeks to observe in vitro effects upon murine neuroblastoma cells (N2A) by these three types of particles …


Paint Pavement Marking Performance Prediction Model That Includes The Impacts Of Snow Removal Operations, Dale M. Mull Mar 2011

Paint Pavement Marking Performance Prediction Model That Includes The Impacts Of Snow Removal Operations, Dale M. Mull

Theses and Dissertations

The results of this research effort were captured in two manuscripts drafted for publication in peer reviewed journals. The first manuscript validated a previously published model with an expanded data set, updated service life predictions for painted pavement markings using recently released pavement marking retroreflectivity minimums, and incorporated recent cost data to evaluate two alternative methods of compliance with the new retroreflectivity minimums for two-lane roads. The second manuscript developed a new performance prediction model for paint pavement markings that includes the impact of snow removal operations and then applied the model to four real-world roadways to determine if replacement …


Modeling Vertical Flow Treatment Wetland Hydraulics To Optimize Treatment Efficiency, David T. Roen Ii Mar 2011

Modeling Vertical Flow Treatment Wetland Hydraulics To Optimize Treatment Efficiency, David T. Roen Ii

Theses and Dissertations

An upward Vertical Flow Treatment Wetland (uVFTW) at Wright Patterson AFB designed to bioremediate contaminated groundwater exhibits hydraulic short-circuiting. Prior studies estimated that groundwater flowed through less than 50% of the wetland’s volume, and that the mean residence time was significantly less than the nominal residence time, which was calculated assuming flow through the entire wetland volume. The objective of this research was to investigate how uVFTW hydraulics affects treatment efficiency, and to propose design strategies to maximize treatment efficiency. A groundwater flow and contaminant transport model of a uVFTW that couples hydraulics and degradation kinetics was built and applied …


Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter Mar 2011

Modeling Enhanced Storage Of Groundwater Contaminants Due To The Presence Of Cracks In Low Permeability Zones Underlying Contaminant Source Areas, Jeremy M. Miniter

Theses and Dissertations

Throughout DoD, chlorinated aliphatic hydrocarbons (CAHs), a type of Dense Non-Aqueous Phase Liquid (DNAPL), have been frequently used. In the subsurface, spilled DNAPLs may pool atop low permeability clay layers. In this study a numerical model is constructed using the Groundwater Modeling System to assess how cracks in the clay, either pre-existing or the result of DNAPL-clay interactions, might impact a dissolved CAH plume generated by the DNAPL source. The conceptual model posits a DNAPL source in a high permeability sand aquifer sitting atop a low permeability clay layer. The model assumes dissolved CAH generated by the DNAPL is transported …


Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker Mar 2011

Retrospective Geospatial Modeling Of Pm10 Exposures From Open Burning At Joint Base Balad, Iraq, John P. Rinker

Theses and Dissertations

Predicting, determining, and linking theater-related source-specific exposures to health effects has proven difficult. The purpose of this research is to delineate retrospective exposure zones using spatially interpolated particulate air sampling point data from Joint Base Balad, create burn pit exposure isopleths from dispersion model outputs, and merge into a combined exposure model in GIS. Interpolated monitoring results and dispersion modeled results were combined to compare modeled exposures across base. Burn pit contribution to total PM10 was also modeled. The combined dispersion and interpolation map showed elevated concentrations within a 1 kilometer buffer of the burn pit. Buildings within this area …


Understanding Schedule Forecasting Shortfalls In Federal Design-Build Facility Procurement, Timothy W. Gannon Mar 2011

Understanding Schedule Forecasting Shortfalls In Federal Design-Build Facility Procurement, Timothy W. Gannon

Theses and Dissertations

This research explores whether initial schedules provide reliable forecasting for project control in federal design build facility procurement. The purpose of this research is to understand how scheduling operates in the Department of Defense environment and identify how project change underscores schedule uncertainty. The research methodology involves a comparative analysis of project schedule data from three case studies. The investigation documents how initial project schedules fail to sufficiently forecast and provide a reliable baseline for total cost, final duration, and activity count for three design-build projects. Most schedule variability occurs after the 100% design benchmark. Furthermore, activity growth highlights the …


Application Of Relational Contracting Methods To Federal Construction Projects, Travis R. Johnson Mar 2011

Application Of Relational Contracting Methods To Federal Construction Projects, Travis R. Johnson

Theses and Dissertations

Relational contracting is a method designed to improve relationships between contracted parties. The federal construction sector was a leader in the development and implementation of an early form of relational contracting known as partnering. Since then, alliancing has emerged as the new evolution of relational contracts. While it provides many potential benefits to contracting parties, alliancing has not yet been utilized in federal construction procurement, which is subject to stringent regulations. A commercially available standard form alliancing contract was selected for analysis against the Federal Acquisition Regulation. Key practices that characterize the alliancing method were identified. Utilizing a panel of …


Impact Of Snow Removal Operations On Thermoplastic Pavement Markings, Monica L. Monfette Mar 2011

Impact Of Snow Removal Operations On Thermoplastic Pavement Markings, Monica L. Monfette

Theses and Dissertations

This pilot study explored the effect snow removal operations have on thermoplastic pavement markings. Including snow removal as a separate independent variable is unique because much of the previous research performed on pavement marking degradation mentioned snow removal as a direct cause in a marking degrading more rapidly; however, it is mentioned as an afterthought and a suggestion to be considered in future research. This pilot study looked at 10 thermoplastic markings and all marking data were collected in the field, using a hand-held retroreflectometer. Data collected began 60 days after initial marking application and ended 12 months after initial …


Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham Mar 2011

Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham

Theses and Dissertations

Polyurea is a long life pavement marking material used for assets requiring long periods of uninterrupted accessibility. Knowing the performance characteristics of such markings is critical to asset management planning focused on maximizing marking material life-cycles. This paper presents the performance characteristics of polyurea pavement markings in North Carolina using linear regression models. The models generated by this research provide pavement marking managers with tools to better allocate limited manpower and resources in order to optimize budgets while meeting newly proposed pavement marking retroreflectivity levels of service as proposed by the Federal Highway Administration. This research constructed performance models for …