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Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng Jan 2005

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …


Computer-Simulation-Assisted Lean Manufacturing Training, Luoding Wang Jan 2005

Computer-Simulation-Assisted Lean Manufacturing Training, Luoding Wang

Theses and Dissertations

This thesis assesses the potential of using computer simulation to aid existing lean manufacturing training methods such as lecture and live simulation. An investigation of this possibility was carried out in conjunction with UMEP's Lean 101 class. In the study, two experimental computer simulation models demonstrating the push and pull production scenarios were constructed using ProModel software. Simulation models were equipped with a Visual Basic interface to aid trainees to manipulate the model via ActiveX. Constructed computer simulation was compared with live simulation to answer these research questions: 1. Was computer simulation able to teach additional lean concepts not covered …


Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock Jan 2005

Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

On/off operation and excess combustion air reduce boiler energy efficiency. This paper presents methods to quantify energy savings from switching to modulation control mode and reducing excess air in natural gas fired boilers.

The methods include calculation of combustion temperature, calculation of the relationship between internal convection coefficient and gas flow rate, and calculation of overall heat transfer assuming a parallel-flow heat exchanger model. The method for estimating savings from changing from on/off to modulation control accounts for purge and drift losses through the boiler and the improved heat transfer within the boiler due to the reduced combustion gas flow …


Identifying Crash Propensity Using Specific Traffic Speed Conditions, Mohamed Abdel-Aty, Anurag Pande Jan 2005

Identifying Crash Propensity Using Specific Traffic Speed Conditions, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

Introduction: In spite of recent advances in traffic surveillance technology and ever-growing concern over traffic safety, there have been very few research efforts establishing links between real-time traffic flow parameters and crash occurrence. This study aims at identifying patterns in the freeway loop detector data that potentially precede traffic crashes.

Method: The proposed solution essentially involves classification of traffic speed patterns emerging from the loop detector data. Historical crash and loop detector data from the Interstate-4 corridor in the Orlando metropolitan area were used for this study. Traffic speed data from sensors embedded in the pavement (i.e., loop …


Regional Scale Evidence For Improvements In Surface Water Chemistry 1990-2001, B. L. Skjelkvåle, J. L. Stoddard, D. S. Jeffries, K. Tørseth, T. Høgåsen, J. Bowman, J. Mannio, D. T. Monteith, R. Mosello, M. Rogora, D. Rzychon, J. Vesely, J. Wieting, A. Wilander, A. Worsztynowicz Jan 2005

Regional Scale Evidence For Improvements In Surface Water Chemistry 1990-2001, B. L. Skjelkvåle, J. L. Stoddard, D. S. Jeffries, K. Tørseth, T. Høgåsen, J. Bowman, J. Mannio, D. T. Monteith, R. Mosello, M. Rogora, D. Rzychon, J. Vesely, J. Wieting, A. Wilander, A. Worsztynowicz

United States Environmental Protection Agency: Publications

The main aim of the international UNECE monitoring program ICP Waters under the Convention of Long-range Transboundary Air Pollution (CLRTAP) is to assess, on a regional basis, the degree and geographical extent of the impact of atmospheric pollution, in particular acidification, on surface waters. Regional trends are calculated for 12 geographical regions in Europe and North America, comprising 189 surface waters sites. From 1990-2001 sulphate concentrations decreased in all but one of the investigated regions. Nitrate increased in only one region, and decreased in three North American regions. Improvements in alkalinity and pH are widely observed. Results from the ICP …


Mole Drainage For Increased Productivity In The South West Irrigation Area, D L. Bennett, Richard George, Bill Russell Jan 2005

Mole Drainage For Increased Productivity In The South West Irrigation Area, D L. Bennett, Richard George, Bill Russell

Bulletins 4000 -

Heavy soils, with low rates of soil-water movement, such as those found in the South-West Irrigation Area (SWIA), require closely spaced (2-6 m apart) subsoil drainage systems to provide sufficient water movement to control the effects of salt-waterlogging on pastures. Such close spacing using traditional buried pipe or tile drainage systems is impractical. As a result, mole drainage systems, used in other parts of the world for over 50 years, have gained popularity in the SWIA in recent years.

This Bulletin Farmnote reports the current ‘best-bet’ mole draining technique for SWIA conditions gathered from observations over a number of years …


Modeling Sediment Trapping In A Vegetative Filter Accounting For Converging Overland Flow, M. J. Helmers, D. E. Eisenhauer, Thomas G. Franti, Michael G. Dosskey Jan 2005

Modeling Sediment Trapping In A Vegetative Filter Accounting For Converging Overland Flow, M. J. Helmers, D. E. Eisenhauer, Thomas G. Franti, Michael G. Dosskey

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vegetative filters (VF) are used to remove sediment and other pollutants from overland flow. When modeling the hydrology of VF, it is often assumed that overland flow is planar, but our research indicates that it can be two-dimensional with converging and diverging pathways. Our hypothesis is that flow convergence will negatively influence the sediment trapping capability of VF. The objectives were to develop a two-dimensional modeling approach for estimating sediment trapping in VF and to investigate the impact of converging overland flow on sediment trapping by VF. In this study, the performance of a VF that has field-scale flow path …


Development Of A Graphical User Interface For Cal3qhc Called Calqcad, Sheetal Gawalpanchi Jan 2005

Development Of A Graphical User Interface For Cal3qhc Called Calqcad, Sheetal Gawalpanchi

Electronic Theses and Dissertations

One of the major sources of air pollution in the United States metropolitan areas is due to automobiles. With the huge growth of motor vehicles and, greater dependence on them, air pollution problems have been aggravated. According to the EPA, nearly 95% of carbon monoxide (CO ) (EPA 1999) in urban areas comes from mobile sources, of which 51% is contributed by on road vehicles. It is well known fact that, carbon monoxide is one of the major mobile source pollutants and CO has detrimental effects on the human health. Carbon monoxide is the result of mainly incomplete combustion of …


A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang Jan 2005

A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang

Electronic Theses and Dissertations

Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition …


Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi Jan 2005

Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi

Electronic Theses and Dissertations

In spite of the most up-to-date investigation of the relevant techniques to analyze the traffic characteristics and traffic operations at a toll plaza, there has not been any note worthy explorations evaluating delay from toll transaction data and using Artificial Neural Networks (ANN) at a toll plaza. This thesis lays an emphasis on the application of ANN techniques to estimate the total vehicular delay according to the lane type at a toll plaza. This is done to avoid the laborious task of extracting data from the video recordings at a toll plaza. Based on the lane type a general methodology …


Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe Jan 2005

Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe

Electronic Theses and Dissertations

Intersection related crashes form a significant proportion of the crashes occurring on roadways. Many organizations such as the Federal Highway Administration (FHWA) and American Association of State Highway and Transportation Officials (AASHTO) are considering intersection safety improvement as one of their top priority areas. This study contributes to the area of safety of signalized intersections by identifying the traffic and geometric characteristics that affect the different types of crashes. The first phase of this thesis was to classify the crashes occurring at signalized intersections into rear-end, angle, turn and sideswipe crash types based on the traffic and geometric properties of …


Numerical Modelling Of Sediments In Cork Harbour, Jérémy Pingon Jan 2005

Numerical Modelling Of Sediments In Cork Harbour, Jérémy Pingon

Theses

In recent years there have been considerable developments in the new and emerging field of hydroinformatics. This relatively new discipline is concerned with the application of computer and networking technology for the planning, management and protection of water bodies.

Environmental issues in estuaries require accurate and detailed knowledge of cohesive sediment transport processes to assess different issues including water quality, pollutant dispersion, and dredging and maintenance of navigation channels.

This thesis presents a review of the main sediment properties and processes required for modelling the behaviour and transport of sediments. It also introduces a new approach to sediment properties using …


Participatory Routing Of Electric Power Transmission Lines Using The Ep-Amis Gis/Multicriteria Evaluation Methodology, Keiron Bailey, Ted H. Grossardt, Ward Jewell Jan 2005

Participatory Routing Of Electric Power Transmission Lines Using The Ep-Amis Gis/Multicriteria Evaluation Methodology, Keiron Bailey, Ted H. Grossardt, Ward Jewell

Kentucky Transportation Center Faculty and Researcher Publications

The North American electric transmission network was developed under the guidance of the North American Electric Reliability Council (NERC) to enhance the reliability of electricity supply. The network also allows sale and marketing of electric power by one utility to another. Electricity marketing has taken on a much more prominent role with restructuring of the electric utility industry. As a result, long-distance sales of electric power have greatly increased the loading of some transmission lines, and have led to congestion on the transmission network. Recent system failures such as the northeast blackout of 2003 have highlighted the need for increased …


Modeling, Simulation And Analysis Of Multi-Barge Flotillas Impacting Bridge Piers, Peng Yuan Jan 2005

Modeling, Simulation And Analysis Of Multi-Barge Flotillas Impacting Bridge Piers, Peng Yuan

University of Kentucky Doctoral Dissertations

The current design code governing bridge structure resistance to vessel impact loads in the U.S. is the American Association of State Highway and Transportation Officials' (AASHTO) Guide Specification and Commentary for Vessel Collision Design of Highway Bridges. The code stipulated method, based on Meir-Dornberg's equivalent static load method, is usually not warranted because of insufficient data on the impact load histories and wide scatter of the impact force values. The AASHTO load equations ignore certain fundamental factors that affect the determination of impact forces and bridge dynamic responses. Some examples of factors that are omitted during standard impact force …


Integration Of Service-Learning Into Civil And Environmental Engineering Curriculum, T. C. Piechota, Shashi S. Nambisan Jan 2005

Integration Of Service-Learning Into Civil And Environmental Engineering Curriculum, T. C. Piechota, Shashi S. Nambisan

Civil and Environmental Engineering and Construction Faculty Research

Service-learning is defined as integrating the community service experience of students with their academic study so that learning is enhanced. The level of student participation in community service is at an all time high as students feel the need to confront today's technical and societal problems. However, service-learning is more than community service or volunteerism. Service-learning as defined above, integrates the community service experience with the student’s academic study (note the hyphen in "service-learning" means that both are considered equal). This enhances learning which is a fundamental goal of colleges and universities. Boyer highlights the need for service-learning stating that …


Assessing Crash Occurrence On Urban Freeways Using Static And Dynamic Factors By Applying A System Of Interrelated Equations, Rajashekar Pemmanaboina Jan 2005

Assessing Crash Occurrence On Urban Freeways Using Static And Dynamic Factors By Applying A System Of Interrelated Equations, Rajashekar Pemmanaboina

Electronic Theses and Dissertations

Traffic crashes have been identified as one of the main causes of death in the US, making road safety a high priority issue that needs urgent attention. Recognizing the fact that more and effective research has to be done in this area, this thesis aims mainly at developing different statistical models related to the road safety. The thesis includes three main sections: 1) overall crash frequency analysis using negative binomial models, 2) seemingly unrelated negative binomial (SUNB) models for different categories of crashes divided based on type of crash, or condition in which they occur, 3) safety models to determine …


Decision Support For Watershed Management Using Evolutionary Algorithms, Misgana K. Muleta, John W. Nicklow Jan 2005

Decision Support For Watershed Management Using Evolutionary Algorithms, Misgana K. Muleta, John W. Nicklow

Civil and Environmental Engineering

An integrative computational methodology is developed for the management of nonpoint source pollution from watersheds. The associated decision support system is based on an interface between evolutionary algorithms (EAs) and a comprehensive watershed simulation model, and is capable of identifying optimal or near-optimal land use patterns to satisfy objectives. Specifically, a genetic algorithm (GA) is linked with the U.S. Department of Agriculture’s Soil and Water Assessment Tool (SWAT) for single objective evaluations, and a Strength Pareto Evolutionary Algorithm has been integrated with SWAT for multiobjective optimization. The model can be operated at a small spatial scale, such as a farm …


Implementation Strategies For Real-Time Traffic Safety Improvements On Urban Freeways, Jeremy Harvey Dilmore Jan 2005

Implementation Strategies For Real-Time Traffic Safety Improvements On Urban Freeways, Jeremy Harvey Dilmore

Electronic Theses and Dissertations

This research evaluates Intelligent Transportation System (ITS) implementation strategies to improve the safety of a freeway once a potential of a crash is detected. Among these strategies are Variable Speed Limit (VSL) and ramp metering. VSL are ITS devices that are commonly used to calm traffic in an attempt to relieve congestion and enhance throughput. With proper use, VSL can be more cost effective than adding more lanes. In addition to maximizing the capacity of a roadway, a different aspect of VSL can be realized by the potential of improving traffic safety. Through the use of multiple microscopic traffic simulations, …


Numerical Modeling Of Dissimilatory Iron Reduction In Sediments At A Field Site, Chun-Wen Chen Jan 2005

Numerical Modeling Of Dissimilatory Iron Reduction In Sediments At A Field Site, Chun-Wen Chen

Electronic Theses and Dissertations

The primary purpose of this study is to identify the 'universal' rate formulations with scaled-dependent parameters for the biological reduction of hematite. Three possible rate formulations were proposed to describe the bioreduction rate of hematite, and two kinds of simulation were conducted to validate the formulations and parameters with both batch and column experimental data: a reaction-based biogeochemical (batch) modeling with BIOGEOCHEM 1.0 and a reactive biogeochemical transport (column) modeling via HYDROGEOCHEM 4.0. Based on the results of simulations, only the dual Monod kinetic with inhibition rate formulation with respect to the concentrations of lactate, ßFeOOH, and Fe2+ under certain …


Three Dimensional Modeling Of Wekiva Springshed With Wash123d, Sandeep Paladagu Jan 2005

Three Dimensional Modeling Of Wekiva Springshed With Wash123d, Sandeep Paladagu

Electronic Theses and Dissertations

This thesis presents a three-dimensional groundwater modeling of Wekia springshed in central Florida using a numerical model, WASH123D. Springs have historically played an important role in Florida's history. The Wekiva River is a spring-fed system associated with about 19 springs connected to the Floridan aquifer. With increased urbanization and population growth in this region, there has been an increased strain on the water levels of Floridan aquifer which is a major source of potable water. Maintaining groundwater recharge to the aquifer is a key factor of the viability of the regional water supply as well as Wekiva ecosystem. Hence, the …


Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo Jan 2005

Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo

Electronic Theses and Dissertations

The computational constitutive Modified Cam Clay Model (MCCM) was developed at Cambridge to study the behavior of clays and has been proven to be effective. In this study, this model is extended to the case of dense sands to analyze the accuracy of the stress-strain behavior. This analysis is based on triaxial test data applied to remolded and compacted sand samples under drained conditions. The laboratory triaxial tests were performed by the Florida Department of Transportation to research the permeability effect in sandy soils compacted up to 95% of maximum unit weight at the optimum moisture content. Each soil sample …


Behavior Of Heat Straightened Plates Bent Along The Minor Axis, Manish Sharma Jan 2005

Behavior Of Heat Straightened Plates Bent Along The Minor Axis, Manish Sharma

LSU Master's Theses

The heat straightening method of repair for damaged steel structures has been employed for many years. The method was based on the experience of practitioners. Recent research has given an engineering background for the technique and established certain procedures and guidelines to be followed while using heat straightening. Although a scientific basis has now been established, there still exist some major gaps in the data. Misuse of the heat straightening technique has produced fractures in the steel during repair.There are two parameters that may be keys to limiting fracture sensitivity: degree of damage and application of jacking force stress during …


Twelve Factors Influencing Sustainable Recycling Of Municipal Solid Waste In Developing Countries , Alexis Manda Troschinetz Jan 2005

Twelve Factors Influencing Sustainable Recycling Of Municipal Solid Waste In Developing Countries , Alexis Manda Troschinetz

Dissertations, Master's Theses and Master's Reports - Open

Sustainable management of solid waste is a global concern, as exemplified by the United Nations Millennium Development Goals (MDG) that 191 member states support. The seventh MDG indirectly advocates for municipal solid waste management (MSWM) by aiming to ensure environmental sustainability into countries’ policies and programs and reverse negative environmental impact. Proper MSWM will likely result in relieving poverty, reducing child mortality, improving maternal health, and preventing disease, which are MDG goals one, four, five, and six, respectively (UNMDG, 2005).

Solid waste production is increasing worldwide as the global society strives to obtain a decent quality of life. Several means …


Comparative Study Of The Physical And Mechanistic Properties Of Hma Mixture: Field Vs Laboratory, Chenggang Zhang Jan 2005

Comparative Study Of The Physical And Mechanistic Properties Of Hma Mixture: Field Vs Laboratory, Chenggang Zhang

LSU Master's Theses

The objectives of this study were to investigate the variability in the physical and mechanistic properties of HMA due to production, characterize and compare the mechanistic properties of roadway cores and laboratory compacted samples, develop the relationship between modulus from in situ NDT and those obtained from laboratory tests on roadway cores, and compare air voids measurements between laboratory and field test methods. Six ongoing rehabilitation projects in Louisiana were selected, in each of which several test sections were tested. Comparative analyses were conducted on density measurements between two laboratory (AASHTO T-166 and ASTM D6752-02, or Vacuum sealing) and one …


Study Of Particle Movement In The Nearshore Region Of Lake Superior With Radioisotope Tracers, Yingtao Chai Jan 2005

Study Of Particle Movement In The Nearshore Region Of Lake Superior With Radioisotope Tracers, Yingtao Chai

Dissertations, Master's Theses and Master's Reports - Open

Biogeochemical processes in the coastal region, including the coastal area of the Great Lakes, are of great importance due to the complex physical, chemical and biological characteristics that differ from those on either the adjoining land or open water systems. Particle-reactive radioisotopes, both naturally occurring (210Pb, 210Po and 7Be) and man-made (137Cs), have proven to be useful tracers for these processes in many systems. However, a systematic isotope study on the northwest coast of the Keweenaw Peninsula in Lake Superior has not yet been performed.

In this dissertation research, field sampling, laboratory measurements and …


Infrared Thermography And High Accuracy Gps For Automated Asphalt Crack Detection, Tarek M. Abdel-Monem Jan 2005

Infrared Thermography And High Accuracy Gps For Automated Asphalt Crack Detection, Tarek M. Abdel-Monem

Electronic Theses and Dissertations

Roads are major public assets. The USA spends billions of dollars each year on road construction and maintenance. To keep these roads in a healthy condition and for better planning and allocation of maintenance budgets, knowledge of distressed locations is needed. Roads develop cracks when they are subjected to stresses that exceed their designed criteria or their materials properties. Early detection and repair of cracks has proven to be the most cost-effective strategy in limiting the damage to roads and reducing expenditures. Various methodologies of crack detection were developed and significant techniques were made in the last few years. One …


Effects Of Bedding Void On Internal Moment Increase In Concrete Pipes, Jad Kazma Jan 2005

Effects Of Bedding Void On Internal Moment Increase In Concrete Pipes, Jad Kazma

Electronic Theses and Dissertations

Large diameter concrete pipes have been used in many areas of central Florida to carry pressured sewage flow. These pipes have been typically located at six feet below finished roadway elevation, and ranges in diameter from thirty six to sixty inches. The water table is typically located at shallow depth below finished roadway elevation, and generally fluctuates between five to ten feet depending on the relative roadway elevation to mean sea level. These pipes are under pressure when carrying the sewage flow, but return to normal atmospheric pressures when the flow stops. Since the water table encases most of the …


Corrugated Wood Composite Panels For Structural Decking, Wei Chiang Pang Jan 2005

Corrugated Wood Composite Panels For Structural Decking, Wei Chiang Pang

Dissertations, Master's Theses and Master's Reports - Open

High flexural strength and stiffness can be achieved by forming a thin panel into a wave shape perpendicular to the bending direction. The use of corrugated shapes to gain flexural strength and stiffness is common in metal and reinforced plastic products. However, there is no commercial production of corrugated wood composite panels. This research focuses on the application of corrugated shapes to wood strand composite panels.

Beam theory, classical plate theory and finite element models were used to analyze the bending behavior of corrugated panels. The most promising shallow corrugated panel configuration was identified based on structural performance and compatibility …


Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta Jan 2005

Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Best utilizing water resources requires coordinating their availability and use in time and space. Required can be: spatially and temporally distributed data; simulators to predict system response to stimuli; procedures for defining management goals, constraints, and scenarios; optimizers to compute optimal management strategies; and appropriate strategy implementation techniques. Here, a strategy is a set of controllable groundwater extraction and injection rates and surface water diversions. Simulation/optimization (S/O) models couple simulators and optimizers to compute optimal strategies for posed management problems. S/O models are becoming more commonly used for policy, planning, system design, and management. For example, water planners and managers …


Aggregate Gradation Optimization -- Literature Search, David Newton Richardson Jan 2005

Aggregate Gradation Optimization -- Literature Search, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.