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Recharge Dynamics Of A Perched Phreatic Aquifer, Joseph Neil Ketchum Jr.
Recharge Dynamics Of A Perched Phreatic Aquifer, Joseph Neil Ketchum Jr.
Graduate Theses, Dissertations, and Problem Reports
Numerous techniques were used to analyze recharge rates, timing, and mechanisms for a perched, phreatic aquifer. Recharge rates were estimated using fluid mass balance (FMB), integrated hydrograph separation (IHS), and innovative hydrograph manipulation techniques. Timing and mechanisms of recharge were analyzed using signal-processing and linear-system approaches. Hydrometeorologic and hydrologic data were collected for a 16-month period (4/97 to 8/98) using both manual and automated techniques. Precipitation totaled 135.6 cm and evapotranspiration (ET) calculated using the Penman-Monteith method totaled 107.5 cm. Recharge estimates from FMB ranged from 20.3% to 33.6%. Springflows were modeled using a stage-discharge cross-correlation method. Recharge estimates from …
Durability Of Fiber-Reinforced Composite Wrap System For The Rehabilitation Of Concrete Structures, Sachin Kshirsagar
Durability Of Fiber-Reinforced Composite Wrap System For The Rehabilitation Of Concrete Structures, Sachin Kshirsagar
Graduate Theses, Dissertations, and Problem Reports
The objective of this research was the investigation of the durability of composite materials employed for rehabilitation of concrete bridge piers. Standard concrete cylinders (4&inches; x 8&inches; in dimensions) wrapped with 1 layer of glass fabric embedded in an epoxy resin matrix were used to simulate the field situation. Wet lay-up method was used to wrap the concrete cylinders where the epoxy also served the purpose of bonding the composite to the concrete. Specimens were subjected to six different accelerated aging conditions: (i) pH 9.4, 73°F; (ii) pH 12.4, 73°F; (iii) pH 12.4, 150°F; (iv) pH 7.0, 150°F; (v) Dry …
Fuzzy Reliability Modeling Of Distributed Client -Server Systems, Patrick Louis Cross
Fuzzy Reliability Modeling Of Distributed Client -Server Systems, Patrick Louis Cross
Graduate Theses, Dissertations, and Problem Reports
With the proliferation of client-server systems there is a need for new approaches to determine their reliability in the uncertain environment of the internet. The proposed methods analyze client-server reliability by accounting for uncertainties in the operational environment of the internet. The uncertainties are addressed with a fuzzy paradigm applied in a tractable, verifiable reliability model of client-server systems. For computer hardware, fuzzy sets were used to address vague reliability data using bi-state fuzzy probabilistic theories. For software and operating systems, fuzzy sets account for the uncertainties in bi-state failure data using fuzzy possibility theories. Client-server architectures, such as hypercubes, …
Outline And Nearly Outline Triple Systems Of Even Index, Michael Neill Ferencak
Outline And Nearly Outline Triple Systems Of Even Index, Michael Neill Ferencak
Graduate Theses, Dissertations, and Problem Reports
The main result of this work describes a completely novel structural result for (v, 3, lambda)-designs in the case when lambda is even. Such designs are known as triple systems. Given a finite collection of n elements, a triple system of order n and index lambda is a collection of subsets of size three chosen from the given set with the property that each distinct pair of elements from the set occurs in exactly lambda of the triples. It is well known for what values of n and lambda such systems exist. A partial triple system of order n and …
Fractal Analysis Of Topography And Structure Across The Appalachian Foreland Of West Virginia, Ashley Shannon Burns Douds
Fractal Analysis Of Topography And Structure Across The Appalachian Foreland Of West Virginia, Ashley Shannon Burns Douds
Graduate Theses, Dissertations, and Problem Reports
Fractal analysis was conducted on topographic relief and seismic reflection travel time data in the state of West Virginia to determine the potential influence of subsurface structure on surface topography. Seismic travel-times digitized from two east-west seismic profiles and topographic relief extracted in north-south and west-east directions from a 1:250,000 Digital Elevation Model (DEM) for the entire state were used in the analysis. A limited local study was also conducted of hand-drawn topographic profiles extracted from U.S.G.S. 1:24,000 topographic quadrangles over the Cottageville gas field in western West Virginia. This study also incorporated extraction of profiles in the same location …
Investigation Of A Paleocatena Across A Late Pennsylvanian Landscape Comprised Of Organic And Mineral Paleosols, Nick Fedorko Iii
Investigation Of A Paleocatena Across A Late Pennsylvanian Landscape Comprised Of Organic And Mineral Paleosols, Nick Fedorko Iii
Graduate Theses, Dissertations, and Problem Reports
Exposures of the Pittsburgh coal bed, its seatearth, and correlative rocks at six sites along a 79 mile-long traverse from Morgantown, West Virginia south to near Burnsville, West Virginia comprise a paleocatena of organic and mineral paleosols formed on a coeval landscape. Northern sites were poorly drained leading to weakly developed Inceptisol profiles in the seatearth followed by thick accumulations of organic matter. More highly evolved profiles developed at the better drained sites to the south contain: highly leached, kaolinitic A horizons; slickensided horizons; subsurface accumulation of iron oxide; strong soil structure; in-situ clay production and translocation; and redoximorphic concentrations …
Emissions Reduction Benefits Of Adapting Electronic Closed Loop Fueling Control On A Mechanically Controlled Spark-Ignited Engine, Frederick Scott Richmond
Emissions Reduction Benefits Of Adapting Electronic Closed Loop Fueling Control On A Mechanically Controlled Spark-Ignited Engine, Frederick Scott Richmond
Graduate Theses, Dissertations, and Problem Reports
Recent government gaseous exhaust emissions regulations have been expanded to include a variety of mobile air pollution sources. Exhaust emissions from non-road engines have recently become a focus of Environmental Protection Agency (EPA) regulations. The term "non-road engines" covers many industrial and general aviation (GA) type engines that are currently unregulated. This study examines the gaseous exhaust gas emissions produced from a mechanically-controlled Lycoming IO-360-B GA engine and studies the benefits of conversion to electronic fuel injection with closed loop feedback control. The study concludes that the overall gaseous exhaust emissions from the unmodified engine far exceed current automotive standards. …