Engineering Commons^™

Hydrologic Monitoring Of An Integrated Low Impact Development (Lid) Underdrained Stormwater Management System , Nancy-Jeanne Bachmann

Dissertations, Master's Theses and Master's Reports - Open

In 2005, Wetland Studies and Solutions, Inc. (WSSI) installed an extensive Low Impact Development (LID) stormwater management system on their new office site in Gainesville, Virginia. The 4-acre site is serviced by a network of LID components: permeable pavements (two proprietary and one gravel type), bioretention cell / rain garden, green roof, vegetated swale, rainwater harvesting and drip irrigation, and slow-release underground detention. The site consists of heavy clay soils, and the LID components are mostly integrated by a series of underdrain pipes. A comprehensive monitoring system has been designed and installed to measure hydrologic performance throughout the LID, underdrained …

Analysis Of Atmospheric Transport And The Effects Of Seasonal And Interannual Transport Variability On Measurements Made At The Pico Mountain Observatory, Jessica Marie Strane

Dissertations, Master's Theses and Master's Reports - Open

A non-hierarchical K-means algorithm is used to cluster 47 years (1960–2006) of 10-day HYSPLIT backward trajectories to the Pico Mountain (PM) observatory on a seasonal basis. The resulting cluster centers identify the major transport pathways and collectively comprise a long-term climatology of transport to the observatory. The transport climatology improves our ability to interpret the observations made there and our understanding of pollution source regions to the station and the central North Atlantic region. I determine which pathways dominate transport to the observatory and examine the impacts of these transport patterns on the O₃, NO_y, NO …

Nitrogen Oxides In The North Atlantic Troposphere: Impacts Of Boreal Wildfire And Anthropogenic Emissions, Maria Val Martin

Dissertations, Master's Theses and Master's Reports - Open

Nitrogen oxides play a crucial role in the budget of tropospheric ozone (O sub(3)) and the formation of the hydroxyl radical. Anthropogenic activities and boreal wildfires are large sources of emissions in the atmosphere. However, the influence of the transport of these emissions on nitrogen oxides and O sub(3) levels at hemispheric scales is not well understood, in particular due to a lack of nitrogen oxides measurements in remote regions. In order to address these deficiencies, measurements of NO, NO sub(2) and NO sub(y) (total reactive nitrogen oxides) were made in the lower free troposphere (FT) over the central North …

Regulation Issues And Prediction Of Natural Estrogen Loads For Wastewater Treatment Plants, Michelle E. Jarvie

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.

Twelve Factors Influencing Sustainable Recycling Of Municipal Solid Waste In Developing Countries , Alexis Manda Troschinetz

Dissertations, Master's Theses and Master's Reports - Open

Sustainable management of solid waste is a global concern, as exemplified by the United Nations Millennium Development Goals (MDG) that 191 member states support. The seventh MDG indirectly advocates for municipal solid waste management (MSWM) by aiming to ensure environmental sustainability into countries’ policies and programs and reverse negative environmental impact. Proper MSWM will likely result in relieving poverty, reducing child mortality, improving maternal health, and preventing disease, which are MDG goals one, four, five, and six, respectively (UNMDG, 2005).

Solid waste production is increasing worldwide as the global society strives to obtain a decent quality of life. Several means …

Quickbird Satellite Imagery For Riparian Management : Characterizing Riparian Filter Strips And Detecting Concentrated Flow In An Agricultural Watershed , Sarah Volkman

Dissertations, Master's Theses and Master's Reports - Open

Riparian ecology plays an important part in the filtration of sediments from upland agricultural lands. The focus of this work makes use of multispectral high spatial resolution remote sensing imagery (Quickbird by Digital Globe) and geographic information systems (GIS) to characterize significant riparian attributes in the USDA’s experimental watershed, Goodwin Creek, located in northern Mississippi. Significant riparian filter characteristics include the width of the strip, vegetation properties, soil properties, topography, and upland land use practices. The land use and vegetation classes are extracted from the remotely sensed image with a supervised maximum likelihood classification algorithm. Accuracy assessments resulted in an …

Corrugated Wood Composite Panels For Structural Decking, Wei Chiang Pang

Dissertations, Master's Theses and Master's Reports - Open

High flexural strength and stiffness can be achieved by forming a thin panel into a wave shape perpendicular to the bending direction. The use of corrugated shapes to gain flexural strength and stiffness is common in metal and reinforced plastic products. However, there is no commercial production of corrugated wood composite panels. This research focuses on the application of corrugated shapes to wood strand composite panels.

Beam theory, classical plate theory and finite element models were used to analyze the bending behavior of corrugated panels. The most promising shallow corrugated panel configuration was identified based on structural performance and compatibility …

Testing Wisconsin Asphalt Mixtures For The 2002 Aashto Mechanistic Design Procedure , Christopher J. Robinette

Dissertations, Master's Theses and Master's Reports - Open

There has been a continuous evolutionary process in asphalt pavement design. In the beginning it was crude and based on past experience. Through research, empirical methods were developed based on materials response to specific loading at the AASHO Road Test. Today, pavement design has progressed to a mechanistic-empirical method. This methodology takes into account the mechanical properties of the individual layers and uses empirical relationships to relate them to performance. The mechanical tests that are used as part of this methodology include dynamic modulus and flow number, which have been shown to correlate with field pavement performance.

This thesis was …

Countermeasures Against Scour At Bridge Abutments, Hua Li

Dissertations, Master's Theses and Master's Reports - Open

Scour at bridge abutments can cause damage or failure of bridges and result in excessive repairs, loss of accessibility, or even death. To mitigate abutment scour, both clear-water and live-bed laboratory experiments in a compound channel were performed using parallel walls and spur dikes as countermeasures, respectively. In addition, collars were tested under clear-water conditions only. It was found that both parallel walls and spur dikes can efficiently protect the abutment from scour provided that they are properly designed. Design guidelines were discussed for both countermeasures. Preliminary clear-water tests of collars as countermeasures against scour showed some promising results although …

Study Of Particle Movement In The Nearshore Region Of Lake Superior With Radioisotope Tracers, Yingtao Chai

Dissertations, Master's Theses and Master's Reports - Open

Biogeochemical processes in the coastal region, including the coastal area of the Great Lakes, are of great importance due to the complex physical, chemical and biological characteristics that differ from those on either the adjoining land or open water systems. Particle-reactive radioisotopes, both naturally occurring (²¹⁰Pb, ²¹⁰Po and ⁷Be) and man-made (¹³⁷Cs), have proven to be useful tracers for these processes in many systems. However, a systematic isotope study on the northwest coast of the Keweenaw Peninsula in Lake Superior has not yet been performed.

In this dissertation research, field sampling, laboratory measurements and …

Optimal Design Of Pump And Treat Remediation Systems : Treatment Modeling, Source Modeling And Time As A Decision Variable, Karen L. Endres

Dissertations, Master's Theses and Master's Reports - Open

Groundwater optimization and simulation is a maturing science. Research work contained in this thesis extends into areas that have not been fully explored. The incorporation of source and treatment systems selection and design produces information to help decision makers. Further insight is gained by evaluating some of the requirements and standards enforced by regulations such as, remediation time.

The technical aspects of a remediation system are set by the physical properties and the regulatory constraints enforced. As an example, the addition of a realistic treatment system gives more accurate cost estimates, but the pump and treat (PAT) systems parameters do …

Topographic And Meteorological Influences On Spatial Scaling Of Heavy Convective Rainfall In Mountainous Regions, Antonio Rubert Godoy

Dissertations, Master's Theses and Master's Reports - Open

Characterizing the spatial scaling and dynamics of convective precipitation in mountainous terrain and the development of downscaling methods to transfer precipitation fields from one scale to another is the overall motivation for this research. Substantial progress has been made on characterizing the space-time organization of Midwestern convective systems and tropical rainfall, which has led to the development of statistical/dynamical downscaling models. Space-time analysis and downscaling of orographic precipitation has received less attention due to the complexities of topographic influences. This study uses multiscale statistical analysis to investigate the spatial scaling of organized thunderstorms that produce heavy rainfall and flooding in …

Evaluating The Usefulness Of Soil Moisture (Forecasts) In Streamflow Prediction For Central Texas , Mohammed Mahmoud

Dissertations, Master's Theses and Master's Reports - Open

The past decade has brought significant advancements in seasonal climate forecasting. However, water resources decision support and management continues to be based almost entirely on historical observations and does not take advantage of climate forecasts. This study builds on previous work that conditioned streamflow ensemble forecasts on observable climate indicators, such as the El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) for use in a decision support model for the Highland Lakes multi-reservoir system in central Texas operated by the Lower Colorado River Authority (LCRA). In the current study, seasonal soil moisture is explored as a climate indicator …

Climatological Study Of Transport To The Pico-Nare Site Using Atmospheric Backward Trajectories, Robert Christopher Owen

Dissertations, Master's Theses and Master's Reports - Open

This study developed a transport climatology to the PICO-NARE station, in the central North Atlantic Ocean, using a 40-year set of atmospheric back trajectories. The trajectory set was subjected to a cluster analysis in order to group trajectories into six flow patterns, or clusters. An air flow probability analysis was conducted in conjunction with the cluster analysis in order to determine the source regions for flow to the site. Seasonal differences in the flow patterns were found, which included enhanced westerly flow in the winter, decreased westerly flow in the summer, and spring and fall having moderate westerly flow. The …

Selected Chemoautotrophic Processes In Wastewater Treatment: Low Temperature Nitrification Inhibition By An Azo Dye And Biofiltration For Odor Control Of Hydrogen Sulfide, Ronald W. Martin Jr.

Dissertations, Master's Theses and Master's Reports - Open

Biochemical processes by chemoautotrophs such as nitrifiers and sulfide and iron oxidizers are used extensively in wastewater treatment. The research described in this dissertation involved the study of two selected biological processes utilized in wastewater treatment mediated by chemoautotrophic bacteria: nitrification (biological removal of ammonia and nitrogen) and hydrogen sulfide (H2S) removal from odorous air using biofiltration.

A municipal wastewater treatment plant (WWTP) receiving industrial dyeing discharge containing the azo dye, acid black 1 (AB1) failed to meet discharge limits, especially during the winter. Dyeing discharge mixed with domestic sewage was fed to sequencing batch reactors at 22oC and 7oC. …