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Full-Text Articles in Engineering
A Joint Data Rate - Error Rate Analysis In Correlated Space-Time-Wireless Channels, Hui Tong
A Joint Data Rate - Error Rate Analysis In Correlated Space-Time-Wireless Channels, Hui Tong
Dissertations, Master's Theses and Master's Reports - Open
No abstract provided.
Localized Annealing Of Polysilicon Microstructures By Inductively Heated Ferromagnetic Films, Melissa L. Trombley
Localized Annealing Of Polysilicon Microstructures By Inductively Heated Ferromagnetic Films, Melissa L. Trombley
Dissertations, Master's Theses and Master's Reports - Open
The monolithic integration of dissimilar microsystems is often limited by conflicts in thermal budget. One of the most prevalent examples is the fabrication of active micro-electromechanical systems (MEMS), as structural films utilized for surface micromachining such as polysilicon typically require processing at temperatures unsuitable for microelectronic circuitry. A localized annealing process could provide for the post-deposition heat treatment of integrated structures without compromising active devices. This dissertation presents a new microfabrication technology based on the inductive heating of ferromagnetic films patterned to define regions for heat treatment. Support is provided through theory, finite-element modeling, and experimentation, concluding with the demonstration …
Hydrologic Monitoring Of An Integrated Low Impact Development (Lid) Underdrained Stormwater Management System , Nancy-Jeanne Bachmann
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
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, NOy, NO …
Non-Intrusive Pressure Measurement In Microchannels, Derek Fultz
Non-Intrusive Pressure Measurement In Microchannels, Derek Fultz
Dissertations, Master's Theses and Master's Reports - Open
A non-intrusive interferometric measurement technique has been successfully developed to measure fluid compressibility in both gas and liquid phases via refractive index (RI) changes. The technique, consisting of an unfocused laser beam impinging a glass channel, can be used to separate and quantify cell deflection, fluid flow rates, and pressure variations in microchannels. Currently in fields such as microfluidics, pressure and flow rate measurement devices are orders of magnitude larger than the channel cross-sections making direct pressure and fluid flow rate measurements impossible. Due to the non-intrusive nature of this technique, such measurements are now possible, opening the door for …
Effect Of Segmented Anodes On The Performance And Plume Of A Hall Thruster, Alexander W. Kieckhafer
Effect Of Segmented Anodes On The Performance And Plume Of A Hall Thruster, Alexander W. Kieckhafer
Dissertations, Master's Theses and Master's Reports - Open
Development of alternative propellants for Hall thruster operation is an active area of research. Xenon is the current propellant of choice for Hall thrusters, but can be costly in large thrusters and for extended test periods. Condensible propellants may offer an alternative to xenon, as they will not require costly active pumping to remove from a test facility, and may be less expensive to purchase. A method has been developed which uses segmented electrodes in the discharge channel of a Hall thruster to divert discharge current to and from the main anode and thus control the anode temperature. By placing …
Nitrogen Oxides In The North Atlantic Troposphere: Impacts Of Boreal Wildfire And Anthropogenic Emissions, Maria Val Martin
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
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.