Environmental Engineering Commons^™

Dynamic Ventilation And Power Output Of Urban Bicyclists, Alexander Y. Bigazzi, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Bicyclist intake of air pollutants is linked to physical exertion levels, ventilation rates, and exposure concentrations. Whereas exposure concentrations have been widely studied in transportation environments, there is relatively scant research linking on-road ventilation with travel conditions and exertion levels. This paper investigates relationships among power output, heart rate, and ventilation rate for urban bicyclists. Heart rate and ventilation rate were measured on-road and combined with power output estimates from a bicycle power model. Dynamic ventilation rates increased by 0.4-0.8% per watt of power output, with a mean lag of 0.8 minutes. The use of physiology (ventilation) monitoring straps and …

Empirical Analysis Of Bus Bunching Characteristics Based On Bus Avl/Apc Data, Wei Feng, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Bus bunching takes place when headways between buses are irregular. Bus bunching is associated with longer waiting times for riders, overcrowding in some buses, and an overall decrease on the level of service and capacity. Understanding the temporal and spatial characteristics and the causes and effects of bus bunching incidents from archived bus data can greatly aid transit agencies to develop efficient mitigation strategies. This paper presents methods to identify and visualize specific time periods and segments where bus bunching incidents occur based on automatic vehicle location (AVL) and automatic passenger count (APC) data. The paper also proposes methods that …

Does The Bicycle Detector Symbol Change Cyclist Queuing Position At Signalized Intersections?, Stefan W. Bussey, Christopher M. Monsere, Peter Koonce

Civil and Environmental Engineering Faculty Publications and Presentations

The Manual of Traffic Control Devices (MUTCD) includes a bicycle detector pavement marking (Section 9C-05) and accompanying explanatory sign (R10-22) which may encourage cyclists to position themselves over detection at traffic signals. This paper presents the results of an observational and survey- based study evaluating the bicycle detector marking. Three minor actuated approaches at signalized intersections with significant bicycle volumes and without bicycle detector markings were selected for treatment. Three configurations were compared: 1) bicycle detector marking only 2) bicycle detector marking with the R10-22 explanatory sign, and 3) an alternative bicycle detector installed over a contrasting green rectangle. Analysis …

Exploring Thresholds For Timing Strategies On A Pedestrian Active Corridor, Sirisha Murthy Kothuri, Peter Koonce, Christopher M. Monsere, Titus Reynolds

Civil and Environmental Engineering Faculty Publications and Presentations

Traditional signal timing policies have typically prioritized vehicles over pedestrians at intersections, leading to undesirable consequences such as large delays and risky crossing behaviors. The objective of this paper is to explore signal timing control strategies to reduce pedestrian delay at signalized intersections. The impacts of change in signal controller mode of operation (coordinated vs. free) at intersections were studied using the micro-simulation software VISSIM. A base model was developed and calibrated for an existing pedestrian active corridor. A hypothetical network of three intersections was used to explore the effects of mode of operation and measures of delay for pedestrians …

Tides And The Swot Mission: Transition From Science Definition Team To Science Team, Brian K. Arbic, Florent Lyard, Aurelien Ponte, Richard D. Ray, James G. Richman, Jay F. Shriver, Edward Zaron, Zhongxiang Zhao

Civil and Environmental Engineering Faculty Publications and Presentations

As the SWOT wide-swath satellite altimeter mission transitions from the Science Definition Team to the Science Team, it is an opportune time to review the progress that has been made with respect to tides, and the work remaining to be done. As with previous altimeter missions, tides present both an opportunity and a challenge for the SWOT mission. The TOPEX/Jason class of altimeters have allowed high-accuracy mapping of open-ocean barotropic tides over their coverage latitudes (66°S to 66°N), but the inter-track spacing of these missions (~150 km) has limited their ability to map smaller-scale features such as shelf tides, coastal …

Assessing Biofiltration Pretreatment For Ultrafiltration Membrane Processes, Andrea Cumming

Electronic Theses and Dissertations

An engineered biological filtration (biofiltration) process treating a nutrient-enriched, low-alkalinity, organic-laden surface water downstream of conventional coagulation-clarification and upstream of an ultrafiltration (UF) membrane process was assessed for its treatment effectiveness. The impact of biofiltration pretreatment on UF membrane performance was evaluated holistically by investigating the native source water chemistry and extending the analysis into the drinking water distribution system. The biofiltration process was also compared in treatment performance to two alternative pretreatment technologies, including magnetic ion exchange (MIEX®) and granular activated carbon (GAC) adsorption. The MIEX®, GAC adsorption, and biologically active carbon (BAC) filtration pretreatments were integrated with conventional …

Color Removal From Pulp Mill Effluent Using Coal Ash Produced From Georgia Power Coal Combustion Plants, Christopher B. Willett

College of Graduate Studies: Theses & Dissertations

Two environmental concerns currently face Georgia: coal fly ash (CFA) waste from coal power plants, and the effluent generated by pulp mills. Pulp mill effluent discolors surface waters into which it is discharged, and has been proven to negatively impact the dissolved oxygen and carbon necessary for aquatic life. The proposed solution is a cost-effective adsorption treatment using an inexpensive but abundantly available waste material: CFA. CFA possesses beneficial properties that allow it to effectively remove contaminants, and is available at significantly reduced cost. The primary research objective was to define treatment parameters that would result in the maximum removal …

Ammonia Oxygen Demand Determination For The Design Of An Oxygenation System In A Water Supply Reservoir, Armond Jenkins

College of Graduate Studies: Theses & Dissertations

The Occoquan Reservoir is a eutrophic reservoir that is part of an indirect potable reuse system. To protect the reservoir water quality, a high quality nitrified product water from a water reclamation facility and an oxygenation system are used during periods of thermal stratification to prevent the onset of anaerobic conditions above the sediments. During the stratified warmest months of the year, oxygen depletion rates exceed nitrate and artificial oxygen supply rates near the dam resulting in ammonia accumulation in the water column. Field observations and laboratory experiments revealed that sediment ammonia release rates ranged from 170-542 mg/m²∙day. …

Numerical Modeling And Analysis Of Tidal Variance And Marsh Productivity In The Guana Tolomato Matanzas National Estuarine Research Reserve, Florida, Amanda S. Tritinger

UNF Graduate Theses and Dissertations

Long term sustainability in salt marsh and mangroves is dependent on dominant species, such as Spartina alterniflora, to capture organic and inorganic sediment. The research analyzes that sustainability. This work demonstrates the prediction of hydrodynamics and biomass density of salt marsh to provide useful information for the planning and mitigation of sea-level rise impacts on marsh sustainability in the Guana Tolomato Matanzas National Estuarine Research Reserve (GTMNERR), Florida. An advanced circulation code was applied to simulate hydrodynamics (i.e., shallow water equations) in the GTMNERR. The model used a set of parameters and conditions based on the GTMNERR domain to predict …

Evaluation Of School Vip Latrines And User Preferences And Motivations For Adopting Communal Sanitation Technologies In Zwedru, Liberia, Sarah J. Ness

USF Tampa Graduate Theses and Dissertations

This thesis has three objectives as follows: 1) to investigate VIP latrine design and establish if the communal school VIP latrines located on the shared campus of Tubman Wilson Institute (TWI) Junior and Senior High School and J.C. Barlee Elementary School were properly designed and constructed, 2) to explore the user preferences and motivations impacting the adoption of these school latrines, and 3) to develop a framework for factors that influence latrine adoption. These goals were formed by the author in response to her Peace Corps experience working at a high school in Zwedru, Liberia from August 2012 to August …

Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh

Theses and Dissertations

The goal of this study is to further advance the state of the art in developing self-sufficient methods to predict the performance of an aerosol filter. The simulation methods developed in this study are based on first principles and consequently, they do not rely on empirical correction factors. These simulation methods can be used to predict the instantaneous collection efficiency and pressure drop of a filter under dust-loading conditions. In the current study, 3-D micro- and macroscale CFD models are developed to simulate the service life of flat-sheet and pleated filters. These CFD micro- and macroscale models are also used …

Effects Of Solids Retention Time And Feeding Frequency On Performance And Pathogen Fate In Semi-Continuous Mesophilic Anaerobic Digesters, Nathan Daniel Manser

USF Tampa Graduate Theses and Dissertations

Anaerobic digestion is a biochemical process in which organic carbon is biodegraded in an oxygen free environment through a microbial consortium. Engineered biological systems used for resource recovery often utilize anaerobic digestion to treat anthropogenic organic wastes by reclaiming the carbon as energy (methane gas) and a soil amendment (biosolids). Small-scale, or household, semi-continuous anaerobic digesters have been used in developed and developing countries for many decades to produce biogas from human and livestock waste, which is used for heating, lighting, and cooking. This application has been shown to improve the quality of life of the user. Although there is …

Direct Membrane Filtration Of Domestic Wastewater: Implications For Coupling With Anaerobic Membrane Bioreactor (Df-Anmbr) For Wastewater Resource Recovery, George H. Dick

USF Tampa Graduate Theses and Dissertations

With the growing use of membranes in the water industry, different methods for using membranes to treat water is still occurring. Enhancing membrane performance is generally performed with extensive pretreatment methods before the feedwater is filtered by the membrane. With the utilization of direct membrane filtration (DF), no pretreatment is performed and the membrane is exposed to raw wastewater. While this may suggest that membrane performance and permeate quality would suffer in the process, DF testing with a 0.03 µm ultrafiltration PVDF membrane showed that relatively high membrane flux was sustained while producing a high quality effluent. Due to the …

Ecological Sanitation In Uganda: Promotion Through Demonstration Facilities And Potential For Ascaris Reduction By Free Ammonia Inactivation Using Stored Urine, John Thomas Trimmer

USF Tampa Graduate Theses and Dissertations

As Uganda works to transform itself into an industrialized, middle-income country in the coming decades, the country is faced with a number of problematic trends that could hinder this transition. High population growth and urbanization are quickly forcing small towns to deal with issues of limited space and the aesthetic conditions within sanitation systems, while declining soil fertility in surrounding rural areas calls into question the future nutritional security of the growing population. Ecological Sanitation (Eco-San) systems, which are designed to recover nutrients from human excreta, may help to address these trends.

Improved sanitation coverage in Uganda is currently estimated …

A Framework For Determining Building Water Cycle Resilience Using A Dynamic Water Resilience Assessment Model (Wram), Caryssa Joustra

USF Tampa Graduate Theses and Dissertations

The aim of this project was to quantitatively measure the resilience of the building water cycle. In order to accomplish this goal, a framework was developed that outlines how building water resilience can be evaluated. The framework presented assumed that resilience describes the fulfillment of system functions; in this case, the system functions considered are those actualized by the building water system. A building water resilience assessment model (WRAM) was developed with the ability to simulate different building water cycles and resilience scenarios. Resilience is dependent on the type and magnitude of a disturbance. Therefore, unique disruption scenarios were developed …