Civil and Environmental Engineering Commons^™

Advanced Treatment Technologies For Mitigation Of Nitrogen And Off-Flavor Compounds In Onsite Wastewater Treatment And Recirculating Aquaculture Systems, Laura C. Rodriguez-Gonzalez

USF Tampa Graduate Theses and Dissertations

Non-point sources (NPS) of pollution are non-discernable, diffuse sources of pollution that are often difficult to localize and in turn mitigate. NPS can include stormwater runoff, agricultural/aquaculture wastes and wastes from small decentralized wastewater treatment systems, such as conventional septic systems. The mitigation of these NPS is imperative to reduce their potential detrimental effects on the water environment. This dissertation addresses novel treatment technologies for the mitigation of nutrients, particularly nitrogen, in Recirculating Aquaculture Systems (RAS) and onsite wastewater treatment systems (OWTS). The removal of trace organics limiting RAS production and water reuse were also investigated.

The first question this …

Autonomous Vehicles: An Empirical Assessment Of Consumers’ Perceptions, Intended Adoption, And Impacts On Household Vehicle Ownership, Nikhil Menon

USF Tampa Graduate Theses and Dissertations

Emerging automotive and transportation technologies have provided revolutionary possibilities in the way we might travel in the future. Major car manufacturers and technology giants have demonstrated significant progress in advancing and testing autonomous vehicles in real-life traffic conditions. Governmental agencies are grappling with how to plan transportation systems for a world with autonomous vehicles. Past research has shown that not all technologies are immediately welcomed by the public. Autonomous Vehicles would have to likely go through a similar phase, and would need to overcome not just technological challenges but also social barriers for successful penetration into the marketplace. Most previous …

Carbon And Nutrient Balances In Microalgal Bioenergy System, Eunyoung Lee

USF Tampa Graduate Theses and Dissertations

This research investigated life cycle environmental impacts and benefits of an integrated microalgae system with wastewater treatment system using an integrated process modeling approach combined with experimentation. The overall goal of this research is to understand energy, carbon and nutrient balances in the integrated system and to evaluate the environmental impacts and benefits of the integrated system from a carbon, nutrient, and energy perspective. In this study, four major research tasks were designed to contribute to a comprehensive understanding of the environmental and economic sustainability of the integrated system, which included development of an integrated co-limitation kinetic model for microalgae …

Quantifying And Modeling Surface Inflow And Groundwater Infiltration Into Sanitary Sewers In Southern Pinellas County, Fl, Megan E. Long

USF Tampa Graduate Theses and Dissertations

Following large rain events, excess flow in sanitary sewers from inflow and infiltration (I/I) cause sanitary sewer overflows (SSO), resulting in significant problems for Pinellas County and the Tampa Bay area. Stormwater enters the sanitary sewers as inflow from improper or illegal surface connections, and groundwater enters the system as infiltration through cracks in subsurface infrastructure. This pilot study was designed to develop methods to separate and quantify the components of I/I and to build a predictive model using flowmeter and rainfall data.

To identify surface inflow, daily wastewater production and groundwater infiltration patterns were filtered from the flow data, …

Recommendation Of A New Transit Performance Measure In The National Transit Database, Fatemeh Baratian-Ghorghi, Hossein Ahmadianyazdi

Journal of Public Transportation

The frequency of incidents negatively changes public perception with regard to the public safety in transit systems. The level of safety expressed as performance measures, ensures contractors and users that a quality safety level is maintained. Both the private and public sectors in the U.S. annually report accurate data to the National Transit Database (NTD) to be used in assessing the progress of the nation's public transportation systems. Although they must provide both the annual report and monthly reports including Safety and Security data, measures are only grouped into the indicators of efficiency and effectiveness of a system and there …

A Fuzzy Ahp Approach To Compare Transit System Performance In Us Urbanized Areas, Xin Li, Yingling Fan, John W. Shaw, Yunlei Qi

Journal of Public Transportation

Public transit systems in the United States often face multiple policy objectives. Typically, stakeholders desire frequent service on an extensive network, but funding and other resources are constrained, creating complicated relationships between service effectiveness goals and business efficiency goals. Using data from the National Transit Map (NTM), this study evaluated the general performance of transit systems across 294 Urbanized Areas (UZAs) in the US, which were stratified into six peer groups based on population. Transit efficiency and effectiveness were compared by developing a composite business efficiency index score and a composite service effectiveness index score for each urbanized area. The …

Evaluating The Effect Of Temporary Casing On Drilled Shaft Rock Socket Capacity, Daniel J. Hagerman

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine the effect on side shear resistance in limestone when temporary casing is used. Due to testing in actual limestone being an unrealistic goal, simulated limestone mixes were prepared and cast into 6 – 42 in. diameter beds. Limestone throughout Florida can be quite varied (e.g. 50-5000 psi) but where stronger limestone is not likely to be penetrated by casing installation. Therefore, target unconfined compressive strengths of the study specimens ranged between 60 psi to 850 psi.

A simulated limestone material was developed based on over 200 cylinders cast for unconfined compression testing …

The Sustainability Of Ion Exchange Water Treatment Technology, Adib Amini

USF Tampa Graduate Theses and Dissertations

This research investigated using a life cycle environmental and economic approach to evaluate IX technology for small potable water systems, allowing for the identification and development of process and design improvements that reduce environmental impacts and costs. The main goals were to evaluate conventional IX in terms of life cycle environmental and economic sustainability, develop a method for improving designs of IX systems from a environmental and economic sustainability standpoint, evaluate potential design improvements, and make the research findings accessible to water professionals through user-friendly tools and frameworks that take into account their feedback. This research provides an understanding, from …

Cwr 4812 Water Resources Design, Sarina Ergas

Service-Learning Syllabi

No abstract provided.

Mechanism Of Cathodic Prevention Of Carbon Steel In Concrete, Krittin Rattakham

USF Tampa Graduate Theses and Dissertations

In this work, I aim to clarify the mechanism that allows steel to attain higher chloride threshold as it is cathodically polarized. Specifically, I seek to provide empirical information on whether an intrinsic (predominantly interfacial effects of polarization) or an extrinsic (predominantly concentration changes due to polarization) mechanism may be dominant in the beneficial effect of polarization. I carried out this experiment with 12 identical concrete specimens, each with a cast-in steel plate, constantly exposed them to high-chloride environment. The specimens were divided into 4 triplicates and polarized at 4 different level from OCP, -200, -300 to -400 mV_{SCE …}

Electrochemical Methods To Characterize Drilled Shaft Deficiencies, Sarah Jo Mobley

USF Tampa Graduate Theses and Dissertations

In recent years drilled shafts have become the preferred foundation method for marine bridges. Typically, the drilled shaft is selected over traditional driven piles due to soil strata encountered, construction economy, increased lateral stiffness requirements, and/or vibration control considerations. The most critical component in drilled shaft construction is borehole stabilization. Wall sloughing or groundwater inclusion can have devastating effects on the strength of the finished shaft however recent research has shown that the materials, more specifically the slurry, used to accomplish stabilization may be having a negative impact on the durability of the finished product. This thesis investigates the durability …

Opportunities To Mainstream Gender In Water And Wastewater Infrastructure Projects: A Case Study In Barbados, Wainella Isaacs

USF Tampa Graduate Theses and Dissertations

According to the World Resources Institute, Barbados is one of seven Caribbean countries ranked as being the most water stressed territories in the world. Prevailing drought conditions for the period 2010-2016 further compromised its water security while confirming predictions of a drier regional Caribbean climate. The simultaneous failing of at least 50-year-old water infrastructure at many points in the distribution network adds to these water stress conditions, and presents a financial burden to the local water utility in the form of lost revenues, and increased energy consumption for pumping.

Climate change and its impacts are not gender-neutral, and water infrastructure …

A Framework For Measuring The Spatial Equity In The Distribution Of Public Transportation Benefits, Seyyed Amir Hosein Mortazavi, Meisam Akbarzadeh

Journal of Public Transportation

This paper proposes that an equitable transit system requires that the geographical distribution of transit service benefits conform to the geographical distribution of the citizens with the greatest need for public transportation. This is the essence of vertical equity. This study calculated “connectivity power,” which reflects public transit service quality in each traffic analysis zone (TAZ) in a city to indicate the amount of benefit that TAZ is receiving from the transit system. The number of carless citizens in each TAZ was also calculated as an index of need to the public transit services in that area. Conformity of need …

Identifying Key Factors Of Rail Transit Service Quality: An Empirical Analysis For Istanbul, Erkan Isikli, Nezir Aydin, Erkan Celik, Alev Taskin Gumus

Journal of Public Transportation

Providing a high quality of service in public transportation is essential to reduce dissatisfactions stemming from traffic congestion and noise. Public transport providers need to find ways to dilute the effects of immoderate use of private cars in big cities while maintaining a sufficient level of customer satisfaction. This study aimed to identify the key service quality (SQ) factors that drive passenger satisfaction in Istanbul’s rail transit (RT) system using data obtained from an extensive survey conducted by the Istanbul Public Transportation Co. A total of 11,116 passengers who used rail transport from May 15–June 3, 2012, and June 17–July …

Impact Of Different Bus Stop Designs On Bus Operating Time Components, Xiaodong Liu, Yao Yang, Meng Meng, Andreas Rau

Journal of Public Transportation

The design of bus stops significantly affects bus operation. The delay time caused by inappropriate bus stop design adversely influences the efficiency of the system. This paper aims to examine the influence of bus stops on bus operating time components through statistical analysis, using Singapore as a case study. Two common types of bus stops, bus bay and curb-side stop, were investigated during the field survey to obtain actual data of bus operation at stops. Sixteen stops were chosen in pairs to compare the differences in operating time at bus stops. Bus operating times, including acceleration time, dwell time, deceleration …

A New Market Segmentation Approach: Evidence From Two Canadian Cities, Dea Van Lierop, Ahmed El-Geneidy

Journal of Public Transportation

Traditionally, transit market research has categorized passengers into two distinct groups: captive riders and choice riders. Market analyses that depend on such broad categories are likely to overlook important details about the needs and desires of their customer base. This study attempts to better understand the complexities of the different groups who take transit by using information from five years of customer satisfaction questionnaires collected by two Canadian transit providers. Employing a series of clustering techniques, the analysis reveals that nine market segments are present across different modes in both transit agencies. Three different overarching groups of transit users are …

Numerical Analysis Of Heat-Curved I-Girders, Antoine Gergess, Rajan Sen

Civil and Environmental Engineering Faculty Publications

Heat curving is a practical and economical process used by steel fabricators for curving structural steel. In this method, the flange edges of a fabricated straight girder are asymmetrically heated to induce residual curvature on cooling. Available analytical methods for predicting the resulting residual stress, strain and curvature are complex and iterative because of the need to account for material and geometric non-linearity. This paper presents a single-step, non-iterative, numerical procedure for determining the effects of heat-curving on residual stress and strain based on a previously developed simplified analysis. Thermal equilibrium equations for idealized heating profiles are first recast in …

Air Transport Versus High-Speed Rail: An Overview And Research Agenda, Xiaoqian Sun, Yu Zhang, Sebastian Wandelt

Civil and Environmental Engineering Faculty Publications

The development of high-speed rail (HSR) services throughout the last decades has gradually blurred the concept of competition and cooperation with air transportation. There is a wide range of studies on this subject, with a particular focus on single lines or smaller regions. This article synthesizes and discusses recently published studies in this area, while aiming to identify commonalities and deviations among different regions throughout the world, covering services from Europe, Asia, and North America. Our meta-analysis reveals that the literature is highly controversial and the results vary substantially from one region to another, and a generalization is difficult, given …

Finding P-Hub Median Locations: An Empirical Study On Problems And Solution Techniques, Xiaoqian Sun, Weibin Dai, Yu Zhang, Sebastian Wandelt

Civil and Environmental Engineering Faculty Publications

Hub location problems have been studied by many researchers for almost 30 years, and, accordingly, various solution methods have been proposed. In this paper, we implement and evaluate several widely used methods for solving five standard hub location problems. To assess the scalability and solution qualities of these methods, three well-known datasets are used as case studies: Turkish Postal System, Australia Post, and Civil Aeronautics Board. Classical problems in small networks can be solved efficiently using CPLEX because of their low complexity. Genetic algorithms perform well for solving three types of single allocation problems, since the problem formulations can be …

Advances In Modelling Connected And Automated Vehicles, Xiaobo Qu, Xiaopeng Li, Meng Wang, Vinayak Dixit

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Evaluation Of Red Rrfb Implementation At Freeway Off-Ramps And Its Effectiveness On Alleviating Wrong-Way Driving, Seckin Ozkul, Pei-Sung Lin

CUTR Faculty Journal Publications

Wrong-way crashes are a major cause for safety concern along freeways and limited access facilities. This study investigated three different aspects of the use of Rectangular Rapid Flashing Beacons (RRFBs): 1) different settings of red RRFBs and their perceived effectiveness on reducing wrong-way driving based on a public opinion survey, 2) the effect of active red RRFBs on the behavior of drivers traveling on adjacent roadways via a before-and-after study, and 3) the effectiveness of red RRFBs on alleviating wrong-way driving on freeway off-ramps by analyzing the percentage of vehicles turning back after observing the red RRFB activation. Based on …

Improvement Assessment Of Bus Serviceability By Proposing Route Revision, Shahrzad Ainkeshavarzi, Hamed Soleimani

CUTR Faculty Journal Publications

Public transit is an essential part of a city’s transportation. An efficient transit system makes a city more sustainable by reducing the number of single occupancy vehicles leading to a reduction in emissions, energy consumption and less congestion on streets. Public serviceability is an important indicator to indicate how good a transit route is determined; however, it could change during the years since population density is variable. This study is intended to do a comparison between serviceability of a bus line in Memphis, Tennessee for one zip code area to point out the necessity of considering route revising in short-term …

Exploring Factors Contributing To Lane Changes During Left Turns On Quadruple Left-Turn Lanes At Signalized Intersections, Fulu Wei, Zhenyu Wang, Jian Lu

CUTR Faculty Journal Publications

Quadruple left-turn lanes are employed gradually at some major intersections in Jilin, China. At these intersections, frequent lane changes during left turns of vehicles can lead to vastly disordered traffic operations. In this study, the factors contributing to lane changes during left turn behaviors at quadruple left-turn lane intersections were interpreted based on a field survey. In total, data on 192 green intervals and 550 individual lane-change behaviors were collected in Changchun, Jilin Province. A lane-changing rate model was established to predict the rate of lane changes during left turns. In addition, an interval selection model was built to estimate …

Assessment Of Changes In Riverine Nitrate In The Sesan, Srepok And Sekong Tributaries Of The Lower Mekong River Basin, Chanta Oeurng, Thomas A. Cochrane, Mauricio E. Arias, Bikesh Shrestha, Thanapon Piman

Civil and Environmental Engineering Faculty Publications

Changes in nitrates are of particular concern in tropical regions undergoing rapid development, as these changes may affect local and downstream riverine ecosystems. This study assessed the spatial and temporal differences in nitrate loads within the Sesan, Srepok, and Sekong (3S) Rivers, the largest tributaries of the Mekong River. Simulation results from a flow and nitrate calibrated SWAT model show large differences in year-to-year nitrate loads, a strong seasonality, and clear variability patterns in monthly nitrate loads in the 3S outlet during the wet season. The annual total nitrate loading from the 3S Rivers account for approximately 30% of the …

Optimal Limited-Stop Bus Routes Selection Using A Genetic Algorithm And Smart Card Data, Yongju Yi, Keechoo Choi, Young-Jae Lee

Journal of Public Transportation

In recent years, express bus service has come into the spotlight by overcoming slow bus operating speeds while maintaining its accessibility when it operates with local bus services. This study developed an optimal limited-stop bus routes selection (LSBRS) guideline as a scenario-based analysis and compared it with case study results. Smart card data and a genetic algorithm (GA) were used to develop the model with different scenarios. Then, total travel time savings as a result of implementing limited-stop bus service generated by the GA model were computed. The effectiveness of each factor was verified by multiple regression analysis, and the …

Passenger Satisfaction And Mental Adaptation Under Adverse Conditions: Case Study In Manila, Andra Charis Mijares, Mio Suzuki, Tetsuo Yai

Journal of Public Transportation

Public transportation systems in several developing cities face congestion, air pollution, and safety problems, yet many passengers use them regularly. This study examines the structure of passenger satisfaction and the role of mental adaptation under such conditions. Metro Manila MRT-3 was analyzed as a case study.

The actual and perceived conditions at the MRT-3 were assessed using surveys. Results of the waiting time and PM_2.5 monitoring surveys revealed that passengers queue for 30 minutes, on average, while being exposed to unsafe levels of PM_2.5. The questionnaire survey results show some discrepancies between actual and perceived values, suggesting …

Regularity Of Public Transport Usage: A Case Study Of Bus Rides In Lisbon, Portugal, Stefan Foell, Santi Phithakkitnukoon, Marco Veloso, Gerd Kortuem, Carlos Bento

Journal of Public Transportation

This paper presents an analysis of regularity in public transport usage based on a large-scale bus transportation data of Lisbon, Portugal. By exploring the combined information from the bus boarding history of riders and bus arrivals at each bus stop, an analysis of individual bus usage was performed. Daily and weekly patterns were extracted, from which it was observed that a rider takes, on average, 2 trips, visits 1.93 distinct stops, and uses 1.55 distinct bus lines daily. Inter-trip time analysis revealed a daily cycle, and a study of the interaction between riders and bus infrastructure explored how usage was …

Innovative Gtfs Data Application For Transit Network Analysis Using A Graph-Oriented Method, Philippe Fortin, Catherine Morency, Martin Trépanier

Journal of Public Transportation

Public transit networks are constantly evolving in the face of frequent economic and social challenges. There exists a large knowledge base on travel demand; however, there is a shortage of information on travel supply and networks. To our knowledge, no analysis tool can, at this point, systematically characterize a network and observe changes over time in a structured and automated manner. This paper addresses this issue and proposes a graph-oriented method for developing an analysis tool that will characterize a single network and then provide the necessary means to compare two distinct networks. A time-expanded model was applied to import …

Applying Ahp And Clustering Approaches For Public Transportation Decisionmaking: A Case Study Of Isfahan City, Alireza Salavati, Hossein Haghshenas, Bahador Ghadirifaraz, Jamshid Laghaei, Ghodrat Eftekhari

Journal of Public Transportation

The main purpose of this paper is to define appropriate criteria for the systematic approach to evaluate and prioritize multiple candidate corridors for public transport investment simultaneously to serve travel demand, regarding supply of current public transportation system and road network conditions of Isfahan, Iran. To optimize resource allocation, policymakers need to identify proper corridors to implement a public transportation system. In fact, the main question is to adopt the best public transportation system for each main corridor of Isfahan. In this regard, 137 questionnaires were completed by experts, directors, and policymakers of Isfahan to identify goals and objectives in …

Assessing Park-And-Ride Efficiency And User Reactions To Parking Management Strategies, Krae E. Stieffenhofer, Michael Barton, Vikash Gayah V.

Journal of Public Transportation

Increasing the number of spaces at overutilized park-and-rides often is not possible due to budgetary and other constraints. Instead, transit agencies may instead seek to maximize the number of people that are able to use the existing spaces through various parking management strategies. Unfortunately, the efficiency of park-and-rides is difficult to measure, so agencies cannot accurately quantify existing use or improvement after parking management strategies have been applied. This study proposed and tested a method to measure the person-efficiency of park-and-ride lots through an onsite audit. Additionally, a user survey was proposed to confirm the audit results and unveil reactions …