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Full-Text Articles in Civil Engineering
Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou
Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou
Open Access Theses
Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …
Graphical Performance Measures For Practitioners To Identify Split Failures, Richard Scott Freije
Graphical Performance Measures For Practitioners To Identify Split Failures, Richard Scott Freije
Open Access Theses
Detector occupancy is commonly used to measure traffic signal performance. Despite improvements in controller computational power, there have been relatively few innovations in occupancy-based performance measures or integration with other data. This thesis introduces and demonstrates the use of graphical performance measures based on detector occupancy ratios to verify potential split failures and other signal timing shortcomings reported to practitioners by the public. The proposed performance measures combine detector occupancy during the green interval, detector occupancy during the first five seconds of the red interval, and phase termination cause (gap out or force off). These are summarized by time of …
Attached-Growth System For Nitrification At Low Temperature, Zhe Sun
Attached-Growth System For Nitrification At Low Temperature, Zhe Sun
Open Access Theses
Attached-growth biological treatment systems have potential to conduct nitrification in cold-temperature climates. In this research, in order to simulate the attached-growth nitrification process (using BOBBER biological reactor) at a real wastewater treatment facility, two laboratory-scale mini-BOBBER systems were installed in a temperature-controlled room and were operated for 101 days with pure ammonium chloride feed solution. Steady-state conditions were approached at 20°C, 15°C, 10°C, and 5°C. In addition, a series of batch experiments were conducted at temperatures of 20°C and 5°C to investigate the relationship between nitrification rate and ammonia-N concentration. Results from these experiments were analyzed and compared with the …