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Full-Text Articles in Engineering

Flexible Urban Drainage Systems In New Land-Use Areas, Jochen Eckart Jun 2012

Flexible Urban Drainage Systems In New Land-Use Areas, Jochen Eckart

USF Tampa Graduate Theses and Dissertations

Urban drainage systems are influenced by several future drivers that affect the performance as well as the costs of the systems. The uncertainties associated with future drivers and their impact creates difficulties in designing urban drainage systems sustainably. A review of the different future drivers for urban drainage systems illustrates that no sufficient future predictions for the long operational life spans of the systems are possible. This dissertation contends that to deal with future uncertainties, flexibility in urban drainage systems is necessary.

At present, profound insights about defining, measuring, and generating flexible urban drainage systems do not exist. This research …


Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan May 2012

Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan

USF Tampa Graduate Theses and Dissertations

Over the past century the study of gas exchange rates between the atmosphere and the ocean has received increased attention because of concern about the fate of greenhouse gases such as CO2 released into the atmosphere. Of interest is the oceanic uptake of CO2 in shallow water coastal regions as biological productivity in these regions is on average about three times larger than in the open ocean. It is well-known that in the absence of breaking surface waves, the water side turbulence controls gas transfer of sparingly soluble gases such as CO2 from the air to the …


Modeling Travel Time And Reliability On Urban Arterials For Recurrent Conditions, Prony Bonnaire Fils Apr 2012

Modeling Travel Time And Reliability On Urban Arterials For Recurrent Conditions, Prony Bonnaire Fils

USF Tampa Graduate Theses and Dissertations

Abstract

Travel time reliability is defined as the consistency or dependability in travel times during a specified period of time under stated conditions, and it can be used for evaluating the performance of traffic networks based on LOS (Level of Service) of the HCM (Highway Capacity Manual). Travel time reliability is also one of the most understood measures for road users to perceive the current traffic conditions, and help them make smart decisions on route choices, and hence avoid unnecessary delays (Liu & Ma, 2009). Therefore, travel time reliability on urban arterials has become a major concern for daily commuters, …


Understanding Operating Speed Variation Of Multilane Highways With New Access Density Definition And Simulation Outputs, Bing Huang Apr 2012

Understanding Operating Speed Variation Of Multilane Highways With New Access Density Definition And Simulation Outputs, Bing Huang

USF Tampa Graduate Theses and Dissertations

Traffic speed is generally considered a core issue in roadway safety. Previous studies show that faster travel is not necessarily associated with an increased risk of being involved in a crash. When vehicles travel at the same speed in the same direction (even high speeds, as on interstates), they are not passing one another and cannot collide as long as they maintain the same speed. Conversely, the frequency of crashes increases when vehicles are traveling at different rates of speed. There is no doubt that the greater speed variation is, the greater the number of interactions among vehicles is, resulting …


Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter Mar 2012

Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter

USF Tampa Graduate Theses and Dissertations

A simple anaerobic digestion model has been developed for a continuously-stirred tank reactor (CSTR), which links the specific biogas production rate to the food/microorganism ratio (F/M). The model treats the various microbial populations involved in the sequential biological processes involved in anaerobic digestion as a composite and links the entire biomass specific growth rate directly to the specific biogas production rate. The model was calibrated by determining the specific gas production rate for a range of F/M values using a municipal wastewater seed sludge. The model predictions for steady-state biogas production rates were compared to observed biogas production and volatile …


Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard Mar 2012

Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard

USF Tampa Graduate Theses and Dissertations

Self supply is an emerging approach to water supply which focuses on fostering household investment in incremental improvements to their water sources. When successful, it can lower costs and increase sustainability by offering users a larger share

of ownership in their own supply, and harnessing the already existing strengths of a community rather than trying to impose an external perspective. In addition to well upgrading and source protection, one of the key self supply areas is rainwater harvesting.

Uganda has a diverse selection of rainwater storage options, but many of them are scattered and disparate.

The objective of this study …


Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks Mar 2012

Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks

USF Tampa Graduate Theses and Dissertations

In recent years, much focus has been put on the sustainability of water and sanitation development projects. Experts in this field have found that many of the projects of the past have failed to achieve sustainability because of a lack of demand for water and sanitation interventions at a grassroots level. For years projects looked to create this demand through various subsidy schemes, with the "software" of behavior change and education taking a backseat to the "hardware" of infrastructure provision. Community-Led Total Sanitation (CLTS) is a fairly new way of looking at the issues of increasing basic sanitation coverage, promoting …


Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh Mar 2012

Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh

USF Tampa Graduate Theses and Dissertations

While understanding the kinetics of algae growth plays an important role in improving algae cultivation technology, none of the existing kinetic models are able to describe algae growth when more than three growth limiting factors are involved. A model was developed in this study to describe algae growth in a photobioreactor. Two expressions were proposed based on the Monod model to relate the specific growth rate of algae to the concentration of nitrogen, phosphorus, inorganic carbon and light intensity in the culture media. Algal biomass concentration as a function of time was calculated by solving mass and energy balances around …


Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser Mar 2012

Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser

USF Tampa Graduate Theses and Dissertations

It is estimated that only one percent of global freshwater is available to humans, with nearly three billion people living in water scarce conditions. Populations living in impoverished settings are particularly vulnerable to water related illnesses, with approximately 2.2 million people dying each year from to waterborne illnesses. This research uses modeling and field studies to assess the quantity, quality, and economics of distillate produced for drinking water from a brackish water source using two single-sloped, single-basin distillation reactors. The reactors were constructed from adobe and concrete in an arid rural community in San Luis Potosí, Mexico and tested from …


Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick Mar 2012

Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick

USF Tampa Graduate Theses and Dissertations

Land based aquaculture systems are growing in popularity, and there is a drive to improve the efficiency of their energy and water systems for both economic and environmental benefit. Recirculating Aquaculture Systems (RAS) generally refer to systems that recycle their wastewater streams to be more or less a zero discharge facility. A more sustainable approach is emerging in the form of Integrated Aquaculture Systems (IAS) where maximum utility is realized from the various components so that fresh water use is reduced, water quality is improved, energy use is reduced, and new markets are created or fulfilled. Under a grant from …


Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice Jan 2012

Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice

USF Tampa Graduate Theses and Dissertations

Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …


Estimation Of The Impact Of Single Airport And Multi-Airport System Delay On The National Airspace System Using Multivariate Simultaneous Models, Nagesh Nayak Jan 2012

Estimation Of The Impact Of Single Airport And Multi-Airport System Delay On The National Airspace System Using Multivariate Simultaneous Models, Nagesh Nayak

USF Tampa Graduate Theses and Dissertations

Airline delays lead to a tremendous loss of time and resources and cost billions of dollars every year in the United States (U.S.). At certain times, individual airports become bottlenecks within the National Airspace System (NAS). To explore solutions for reducing the delay, it is essential to understand factors causing flight delay and its impact on airports in the NAS. Major causal factors of flight delay at airports include over-scheduling, en-route convective weather, reduced ceiling and visibility around airports, and upstream delay propagation. Delay at one airport can be passed on to other airports in the NAS, in another word, …


On The Development Of The Extradosed Bridge Concept, Steven Lynn Stroh Jan 2012

On The Development Of The Extradosed Bridge Concept, Steven Lynn Stroh

USF Tampa Graduate Theses and Dissertations

The Extradosed Prestressed Bridge represents a relatively new bridge type. The first of this type bridge was constructed in Japan in 1994, and Japan has since built at least 29 examples of this bridge type. Throughout the rest of the world, another 34 of this bridge type have been built, with most countries having only one, or at most a few, examples. A broader application of this bridge type has been hampered by lack of design information and in particular lack design criteria for the stay cables. The purpose of this dissertation is to progress the understanding and application of …


Estimation Of Evapotranspiration And Water Budget Components Using Concurrent Soil Moisture And Water Table Monitoring, Mandana Rahgozar, Nirjhar Shah, Mark Ross Jan 2012

Estimation Of Evapotranspiration And Water Budget Components Using Concurrent Soil Moisture And Water Table Monitoring, Mandana Rahgozar, Nirjhar Shah, Mark Ross

Civil and Environmental Engineering Faculty Publications

Simultaneous measurements of soil moisture profiles and water table heads, along a flow path, were used to determine evapotranspiration (ET) along with other components of the water budget. The study was conducted at a small-scale (~0.8 Km2) hydrologic monitoring field site in Hillsborough County, Florida, from January 2002 to June 2004. Frequency Domain Reflectometry soil moisture probes, installed in close proximity to water table monitoring wells were used to derive changes in the soil water storage. A one-dimensional transect model was developed; changes in the soil water storage and water table observations served as input to determine all vertical and …


Numerical Simulation Of Sliding Friction And Wet Traction Force On A Smooth Tire Sliding On A Random Rough Pavement, Janaka Vishwanath Kosgolla Jan 2012

Numerical Simulation Of Sliding Friction And Wet Traction Force On A Smooth Tire Sliding On A Random Rough Pavement, Janaka Vishwanath Kosgolla

USF Tampa Graduate Theses and Dissertations

Availability of analytical and numerical tools that can provide reliable and accurate estimates of wet frictional resistance in different pavements would preclude the need for time consuming field tests. Therefore, many research efforts have been made to develop such tire-pavement friction predictive tools that are invaluable for friction management programs. However, due to the complexity of the problem, most existing tools have been developed based on several simplifying assumptions and without field verification of their predictions. The current study is focused on the evaluation of two specific prediction methods that can be used to predict friction on a smooth tire …


Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales Jan 2012

Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales

USF Tampa Graduate Theses and Dissertations

The David L. Tippin Water Treatment Facility (DLTWTF) serving the city of Tampa, Florida is an advanced drinking water treatment facility consisting of coagulation/flocculation, ozonation, granular activated carbon biofiltration, and disinfection by chloramine. New regulations and the recent economic crisis pushed the facility to investigate methods to decrease costs and meet regulatory requirements easier.

The two major issues identified as priorities for investigation were the optimization of the biofiltration system and the use of a novel process to reduce the formation of bromate during ozonation.

Optimization of the biofiltration system is needed to remove more of the assorted particles that …


Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor Jan 2012

Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor

USF Tampa Graduate Theses and Dissertations

The two objectives of this work were to develop a simplified method for the analysis of chlorinated organics in water samples and to improve an existing soil remediation technology. The contaminants considered for these studies were chlorinated hydrocarbons because of their relative frequency of appearance at contaminated sites. The first half of this study involved the analysis of chlorinated ethenes by gas chromatography with flame ionization detection (GC-FID). I tested the hypothesis that the FID response factor is the same for all chlorinated ethene compounds. The rationale for this investigation is that if the hypothesis is correct, a single calibration …


Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin Jan 2012

Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.

Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …


Development And Application Of Its Operations Evaluation Models (Itsoems), Gummadavelly Narasimha Murthy Jan 2012

Development And Application Of Its Operations Evaluation Models (Itsoems), Gummadavelly Narasimha Murthy

USF Tampa Graduate Theses and Dissertations

Intelligent Transportation Systems (ITS) play an important role in supporting motorists and first responders to handle major incidents, hazmat spills, security measures and other emergency operations. Increasingly, technology advancements and applications are providing invaluable integration opportunities to interconnect safety, maintenance, ITS, traffic operations, facilities, and transportation equipment programs to maximize available resources and achieve efficiency in transportation operations.

This research focuses on one of the prominent ITS devices: Dynamic Message Signs (DMS) operations. Using real time incident management operations data and ITS operations data, an attempt is made to develop ITS Operations Evaluations Models (ITSOEMs) that are capable of quantifying …


Corrosion Evaluation And Durability Estimation Of Aluminized Steel Drainage Pipes, Mersedeh Akhoondan Jan 2012

Corrosion Evaluation And Durability Estimation Of Aluminized Steel Drainage Pipes, Mersedeh Akhoondan

USF Tampa Graduate Theses and Dissertations

Aluminized steel pipes are expected to have a long service life, e.g. 75 years. Spiral ribbed aluminized pipes (SRAP) have been widely specified and used by the Florida Department of Transportation (FDOT) for drainage of runoff water. Confidence in the long term durability of SRAP has been challenged by recent unexpected early corrosion failures in various Florida locations. SRAP premature corrosion incidents have occurred in two modalities. Mode A has taken place in near-neutral soil environments and has often been associated with either gross manufacturing defects (i.e. helical cuts) or corrosion concentration at or near the ribs. Mode B took …


Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody Jan 2012

Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody

USF Tampa Graduate Theses and Dissertations

Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006).

This study analyzed one such HWTS, the ceramic pot water …


Water's Dependence On Energy: Analysis Of Embodied Energy In Water And Wastewater Systems, Weiwei Mo Jan 2012

Water's Dependence On Energy: Analysis Of Embodied Energy In Water And Wastewater Systems, Weiwei Mo

USF Tampa Graduate Theses and Dissertations

Water and wastewater treatment is a critical service provided for protecting human health and the environment. Over the past decade, increasing attention has been placed on energy consumption in water and wastewater systems for the following reasons: (1) Water and energy are two interrelated resources. The nexus between water and energy can intensify the crises of fresh water and fossil fuel shortages; (2) The demand of water/wastewater treatment services is expected to continue to increase with increasing population, economic development and land use change in the foreseeable future; and (3) There is a great potential to mitigate energy use in …


Assessing The Reuse Potential Of Wastewater For Irrigation: The Removal Of Helminth Eggs From A Uasb Reactor And Stabilization Ponds In Bolivia, Matthew Eric Verbyla Jan 2012

Assessing The Reuse Potential Of Wastewater For Irrigation: The Removal Of Helminth Eggs From A Uasb Reactor And Stabilization Ponds In Bolivia, Matthew Eric Verbyla

USF Tampa Graduate Theses and Dissertations

Extreme hunger, malnutrition, and the lack of access to sanitation are among the most pressing development challenges, but the world is not on track to meet the targets that have been established by the Millennium Development Goals. The integration of wastewater treatment and food production systems allows for the recovery of resources from wastewater, and can provide an important solution to meet the sanitation needs of growing urban populations and provide periurban farmers with a consistent supply of water and nutrients. Stabilization ponds have been long considered to be an appropriate technology for wastewater reuse systems in developing countries, but …


2d And 3d Imaging Of The Metamorphic Carbonates At Omalos Plateau/Polje, Crete, Greece By Employing Independent And Joint Inversion On Resistivity And Seismic Data, Hamdan Ali Hamdan Dr, Nikos Economou, Giorgos Kritikakis, Nikos Andronikidis, Emmanuil Manoutsoglou, Antonis Vafidis, Pangratis Pangratis, Georgina Apostolidou Jan 2012

2d And 3d Imaging Of The Metamorphic Carbonates At Omalos Plateau/Polje, Crete, Greece By Employing Independent And Joint Inversion On Resistivity And Seismic Data, Hamdan Ali Hamdan Dr, Nikos Economou, Giorgos Kritikakis, Nikos Andronikidis, Emmanuil Manoutsoglou, Antonis Vafidis, Pangratis Pangratis, Georgina Apostolidou

International Journal of Speleology

A geophysical survey carried out at Omalos plateau in Chania, Western Crete, Greece employed seismic as well as electrical tomography methods in order to image karstic structures and the metamorphic carbonates (Tripali unit and Plattenkalk group) which are covered by post-Mesozoic deposits (terra rossa, clays, sands and gravels). The geoelectrical sections image the metamorphic carbonates which exhibit a highly irregular relief. At the central part of the plateau the thickness of post-Mesozoic deposits (terra rossa, clays, sands and gravels) ranges from 40-130 m. A 3D resistivity image was generated by inverting resistivity data collected on a grid to the south …