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Full-Text Articles in Engineering

Comparison Of Safety Performance By Design Types At Freeway Diverge Areas And Exit Ramp Sections, Hongyun Chen Dec 2010

Comparison Of Safety Performance By Design Types At Freeway Diverge Areas And Exit Ramp Sections, Hongyun Chen

USF Tampa Graduate Theses and Dissertations

The primary objective of the study is to evaluate the safety performance of different freeway exit types used in current practical designs. More specific, the research objectives include the following two parts: 1) to compare the safety performance of different design types at freeway diverge areas and exit ramp sections; and 2) to identify the impact factors contributing to the crashes happening at these two specific segments.

The study area includes four subjects, the freeway widely-spaced diverge areas; the freeway closely-spaced diverge areas; the left-side off-ramps and the exit ramp sections. For the freeway diverge areas, design types were defined …


Modeling And Predicting Taxi Times At Airports, Arjun Chauhan Oct 2010

Modeling And Predicting Taxi Times At Airports, Arjun Chauhan

USF Tampa Graduate Theses and Dissertations

This research aims at providing methods in analyzing and estimating the taxi times of aircraft at airports, which are expected to be an important element for reducing taxiing delay and consequent excess fuel consumption and environmental costs. The proposed model involves a set of regression equations to model the taxi-out and taxi-in times at airports. The estimated results can be used to calculate the nominal taxi times, which are essential measures for evaluating the taxiing delays at airports. Given the outcomes of the regression model, an iterative algorithm is developed to predict taxi times. A case study at LGA shows …


The Green And Ampt Infiltration Model Accounting For Air Compression And Air Counterflow In The Shallow Water Table Environment: Laboratory Experiments, Yuliya Lukyanets Oct 2010

The Green And Ampt Infiltration Model Accounting For Air Compression And Air Counterflow In The Shallow Water Table Environment: Laboratory Experiments, Yuliya Lukyanets

USF Tampa Graduate Theses and Dissertations

Water infiltration into the unsaturated zone especially in a shallow water table environment is affected by air compression ahead of the wetting front and air counterflow. Neglecting air compression in infiltration modeling can overestimate infiltration and infiltration rates, whereas not accounting for air counterflow can underestimate infiltration and infiltration rates due to unrealistic buildup of air pressure resistance ahead of the wetting front. A method, derived on the basis of the Green and Ampt (1911) infiltration model, is introduced to simulate air compression and air counterflow during infiltration into a shallow water table. The method retains the simplicity of the …


Env Engineering Engagement, Maya Trotz Oct 2010

Env Engineering Engagement, Maya Trotz

Service-Learning Syllabi

No abstract provided.


A Roof Runoff Strategy And Model For Augmenting Public Water Supply, Robert Carnahan Aug 2010

A Roof Runoff Strategy And Model For Augmenting Public Water Supply, Robert Carnahan

USF Tampa Graduate Theses and Dissertations

Water is the essential resource that is becoming extremely scarce worldwide. The 21st century will further stress all available water resources through the growth and expansion of developing nations. It is not only the quantity of cheap water that is being depleted, but the quality of these waters is being endangered. Florida is an example where rapid development and an exploding population are competing for shrinking groundwater resources. Current water use does not address the use of alternative supplies and reuses in the United States.

The objective of this research was to determine a strategy for augmenting existing water supplies …


Enhancement Of Predictive Capability Of Transit Boardings Estimation And Simulation Tool (Tbest) Using Parcel Data: An Exploratory Analysis, Tejsingh Rana Aug 2010

Enhancement Of Predictive Capability Of Transit Boardings Estimation And Simulation Tool (Tbest) Using Parcel Data: An Exploratory Analysis, Tejsingh Rana

USF Tampa Graduate Theses and Dissertations

TBEST is a comprehensive third generation transit demand forecasting model, developed by the FDOT Public Transit Office (PTO) to help transit agencies in completing their Transit Development Plans (TDPs). The on-going project funded by FDOT, related to TBEST, aims at further enhancing the capabilities of the TBEST model based on additional opportunities identified by the research team. The project focuses on enhancing TBEST’s capabilities in following areas: 1) Improving the precision of socio- demographic data by using property appraisal data (parcel data) and, 2) Improving the quality of data regarding trip attraction. Based on the improvement areas, this study aims …


An Analysis Of The Travel Patterns And Preferences Of The Elderly, Sujan Sikder Aug 2010

An Analysis Of The Travel Patterns And Preferences Of The Elderly, Sujan Sikder

USF Tampa Graduate Theses and Dissertations

The number of elderly is increasing; to meet their transportation needs, it is important to clearly understand their travel patterns and preferences. Since travel patterns and preferences depend on socio-demographic and other factors, it is essential to identify these factors first to understand the travel behavior of the elderly. The main purpose of this thesis is to analyze the travel patterns and preferences of the elderly age 65 and above using 2009 National Household Travel Survey (NHTS) data. This thesis presents a detailed descriptive analysis of 2009 NHTS data to understand the travel patterns of the elderly. Along with a …


Ecotourism And Water Quality: Linking Management, Activities And Sustainability Indicators In The Caribbean, Ken Darrie Thomas May 2010

Ecotourism And Water Quality: Linking Management, Activities And Sustainability Indicators In The Caribbean, Ken Darrie Thomas

USF Tampa Graduate Theses and Dissertations

Ecotourism from its genesis and founding theories has been set out to conserve and preserve the environment through sustainable operation that includes surrounding communities in efforts to reduce their poverty levels. Over the years ecotourism has been hypothesized to have departed from this ideal with several researchers, through social, qualitative analyses, have said that these non-sustainable ecotourism operations are simply due to poor management. This work sought to test this central hypothesis as a first approach to quantitatively linking ecotourism activities to management with surface water quality as the key indicator of sustainable ecotourism as a complex system through systems …


Polarization Of Galvanic Point Anodes For Corrosion Prevention In Reinforced Concrete, Margareth Dugarte Apr 2010

Polarization Of Galvanic Point Anodes For Corrosion Prevention In Reinforced Concrete, Margareth Dugarte

USF Tampa Graduate Theses and Dissertations

The polarization performance of two types of commercial galvanic point anodes for protection of reinforced steel around patch repairs was investigated. Experiments included measurement of the polarization history of the anode under constant current impressed by galvanostatic circuits and in reinforced concrete slabs. The tests revealed, for both types of anodes, a potential-current function (PF) indicating relatively little anodic polarization from an open circuit potential at low current levels, followed by an abrupt increase in potential as the current approached an apparent terminal value. Aging of the anodes was manifested by a continually decreasing current output in the concrete tests, …


Mercury In The Environment: Field Studies From Tampa, Bolivia, And Guyana, Joniqua A'Ja Howard Mar 2010

Mercury In The Environment: Field Studies From Tampa, Bolivia, And Guyana, Joniqua A'Ja Howard

USF Tampa Graduate Theses and Dissertations

Tampa (US), Guyana (SA), and Bolivia (SA), are geographically, socially, economically, and politically unique which make them ideal sites to study issues of mercury and sustainability. Mercury’s innate ability to bioaccumulate and biomagnify in aquatic and terrestrial ecosystems poses a severe threat to both human and environmental health. The most vulnerable populations affected by mercury consumption include coastal communities, children, women of child-bearing age, the indigenous poor and persons with high environmental/occupational exposure factors. Communities in the regions of Florida, Bolivia, and Guyana whose diets are high in fish and are environmentally/occupationally exposed to mercury may be at a higher …