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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Development Of A Simplified Finite Element Approach For Frp Bridge Decks., Jignesh Vyas Jan 2006

Development Of A Simplified Finite Element Approach For Frp Bridge Decks., Jignesh Vyas

Electronic Theses and Dissertations

Moveable bridges in Florida typically use open steel grid decks due to the weight limitations. However, these decks present rideability, environmental, and maintenance problems, for they are typically less skid resistant than a solid riding surface, create loud noises, and allow debris to fall through the grids. Replacing open steel grid decks that are commonly used in moveable bridges with a low-profile FRP deck can improve rider safety and reduce maintenance costs, while satisfying the strict weight requirement for such bridges. The performance of the new deck system, which includes fatigue and failure tests were performed on full-size panels in …

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An Assessment Of Alignment Between Project Complexity And Project Management Style, Alper Camci Jan 2006

An Assessment Of Alignment Between Project Complexity And Project Management Style, Alper Camci

Electronic Theses and Dissertations

The main drivers for this research are the complexities associated with the project management and an organization's project management style in dealing with these complexities. This research aims to demonstrate that alignment between project complexity and project management style increases project performance and decreases project issues, and also, with increased project issues, project performance deteriorates. In order to test these claims, this research developed measures for assessing project complexity, project management styles and project issues by employing a survey of project management professionals. The measure for project complexity is based on a taxonomy with four categories: organizational complexity, product complexity, …

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Debris Characterization And Mitigation Of Droplet Laser Plasma Sources For Euv Lithography, Kazutoshi Takenoshita Jan 2006

Debris Characterization And Mitigation Of Droplet Laser Plasma Sources For Euv Lithography, Kazutoshi Takenoshita

Electronic Theses and Dissertations

Extreme ultraviolet lithography (EUVL) is a next generation lithographic techniques under development for fabricating semiconductor devices with feature sizes smaller than 32 nm. The optics to be used in the EUVL steppers is reflective optics with multilayer mirror coatings on each surface. The wavelength of choice is 13.5 nm determined by the optimum reflectivity of the mirror coatings. The light source required for this wavelength is derived from a hot-dense plasma produced by either a gas discharge or a laser. This study concentrate only on the laser produced plasma source because of its advantages of scalability to higher repetition rates. …

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Using Augmented Reality For Studying Left Turn Maneuver At Un-Signalized Intersection And Horizontal Visibility Blockage, Ghada Moussa Jan 2006

Using Augmented Reality For Studying Left Turn Maneuver At Un-Signalized Intersection And Horizontal Visibility Blockage, Ghada Moussa

Electronic Theses and Dissertations

Augmented reality "AR" is a promising paradigm that can provide users with real-time, high-quality visualization of a wide variety of information. In AR, virtual objects are added to the real-world view in a real time. Using the AR technology can offer a very realistic environment for driving enhancement as well as driving performance testing under different scenarios. This can be achieved by adding virtual objects (people, vehicles, hazards, and other objects) to the normal view while driving in a safe controlled environment. In this dissertation, the feasibility of adapting the AR technology into traffic engineering was investigated. Two AR systems; …

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Ten Step Manufacturing Problem Solvingprocess, Afsoun Panahi Jan 2006

Ten Step Manufacturing Problem Solvingprocess, Afsoun Panahi

Electronic Theses and Dissertations

The ten step problem solving is created to capture and resolve all issues that arise with designing, developing, manufacturing and delivering a new vehicle produce. These steps will provide a common process, which effectively defines and resolves concerns and prevents their recurrence. Step 1: Prepare for the process Step 2: Establish Team Step 3: Describe the Problem Step 4: Develop short term containment action Step 5: Define and verify root cause and escape point Step 6: Choose and verify permanent corrective actions Step 7: Implement and validate permanent corrective actions Step 8: Prevent recurrence Step 9: Recognize team and individual …

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Intrusion Detection In Wireless Sensor Networks, Hong Nhung Nguyen Jan 2006

Intrusion Detection In Wireless Sensor Networks, Hong Nhung Nguyen

Electronic Theses and Dissertations

There are several applications that use sensor motes and researchers continue to explore additional applications. For this particular application of detecting the movement of humans through the sensor field, a set of Berkley mica2 motes on TinyOS operating system is used. Different sensors such as pressure, light, and so on can be used to identify the presence of an intruder in the field. In our case, the light sensor is chosen for the detection. When an intruder crosses the monitored environment, the system detects the changes of the light values, and any significant change meaning that a change greater than …

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Improving Routing Efficiency, Fairness, Differentiated Servises And Throughput In Optical Networks, Bin Zhou Jan 2006

Improving Routing Efficiency, Fairness, Differentiated Servises And Throughput In Optical Networks, Bin Zhou

Electronic Theses and Dissertations

Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in next-generation Internet architectures. This dissertation addresses the important issues of improving four aspects of optical networks, namely, routing efficiency, fairness, differentiated quality of service (QoS) and throughput. A new approach for implementing efficient routing and wavelength assignment in WDM networks is proposed and evaluated. In this approach, the state of a multiple-fiber link is represented by a compact bitmap computed as the logical union of the bitmaps of the free wavelengths in the fibers of this link. A modified Dijkstra's shortest path algorithm and a wavelength …

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Ultrawideband Indoor Location And Tracking System, Qing Chen Jan 2006

Ultrawideband Indoor Location And Tracking System, Qing Chen

Electronic Theses and Dissertations

The objective of this thesis is to demonstrate an indoor intruder location and tracking system with UltraWideBand (UWB) technology and use data compression and Constant False Alarm Rate (CFAR) techniques to improve the performance of the location system. Reliable and accurate indoor positioning requires a local replacement for GPS systems since satellite signals are not available indoors. UWB systems are particularly suitable for indoor location systems due their inherent capabilities such as low-power, multi-path rejection, and wide bandwidth. In our application, we are using UWB radios as a radar system for tracking targets in indoor locations. We also use Discrete …

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Modeling, Simulation, And Visualization Of 3d Lung Dynamics, Anand Santhanam Jan 2006

Modeling, Simulation, And Visualization Of 3d Lung Dynamics, Anand Santhanam

Electronic Theses and Dissertations

Medical simulation has facilitated the understanding of complex biological phenomenon through its inherent explanatory power. It is a critical component for planning clinical interventions and analyzing its effect on a human subject. The success of medical simulation is evidenced by the fact that over one third of all medical schools in the United States augment their teaching curricula using patient simulators. Medical simulators present combat medics and emergency providers with video-based descriptions of patient symptoms along with step-by-step instructions on clinical procedures that alleviate the patient's condition. Recent advances in clinical imaging technology have led to an effective medical visualization …

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Optimizing The Global Performance Of Build-To-Order Supply Chains, Tarek Shaalan Jan 2006

Optimizing The Global Performance Of Build-To-Order Supply Chains, Tarek Shaalan

Electronic Theses and Dissertations

Build-to-order supply chains (BOSCs) have recently received increasing attention due to the shifting focus of manufacturing companies from mass production to mass customization. This shift has generated a growing need for efficient methods to design BOSCs. This research proposes an approach for BOSC design that simultaneously considers multiple performance measures at three stages of a BOSC – Tier I suppliers, the focal manufacturing company and Tier I customers (product delivery couriers). We present a heuristic solution approach that constructs the best BOSC configuration through the selection of suppliers, manufacturing resources at the focal company and delivery couriers. The resulting configuration …

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Simulation And Continuance Of Operation For The Use Of Transit (Lynx) To Be Used In Emergency Evacuation Incidents, Noor Elmitiny Jan 2006

Simulation And Continuance Of Operation For The Use Of Transit (Lynx) To Be Used In Emergency Evacuation Incidents, Noor Elmitiny

Electronic Theses and Dissertations

The evacuation planning has become an important issue addressed by many research studies and publications aiming to improve the security of the daily life for our public inside the United States of America. The main objective of this research was to address the growing need for evacuation planning using traffic simulation. With increased interests and awareness in emergency evacuation and first responder access to emergencies in public locations (airports, transit stations, ports or stadiums), the traffic simulation can be helpful in orchestrating the traffic flow during emergencies. Related to this issue, Federal Transit Administration has issued a large number of …

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Verification Of Faa's Emissions And Dispersion Modeling System (Edms), Anjoli Martin Jan 2006

Verification Of Faa's Emissions And Dispersion Modeling System (Edms), Anjoli Martin

Electronic Theses and Dissertations

Air quality has been a major environmental concern for many years. Recently the issue of airport emissions has presented growing concerns and is being studied in much more depth. Airport emissions come from a variety of point, line and area sources, making emissions modeling for airports very complex and more involved. Accurate air quality models, specific to airport needs, are required to properly analyze this complex array of air pollution sources created by airports. Accurate air quality models are needed to plan for increased growth of current airports and address concerns over proposed new ones. The Federal Aviation Administration's (FAA) …

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Density-Functional Theory Applied To Problems In Catalysis And Electrochemistry, Santosh Kumar Jan 2006

Density-Functional Theory Applied To Problems In Catalysis And Electrochemistry, Santosh Kumar

Electronic Theses and Dissertations

We study the structure and energetics of water molecules adsorbed at ceria (111) surfaces below one monolayer coverage using density-functional theory. The results of this study provide a theoretical framework for interpreting recent experimental results on the redox properties of water at ceria (111) surfaces. In particular, we have computed the structure and energetics of various absorption geometries at stoichiometric ceria (111) surface. In contrast to experiment results, we do not find a strong coverage dependence of the adsorption energy. For the case of reduced surface, our results show that it may not be energetically favorable for water to oxidize …

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Sub-Pixel Registration In Computational Imaging And Applications To Enhancement Of Maxillofacial Ct Data, Murat Balci Jan 2006

Sub-Pixel Registration In Computational Imaging And Applications To Enhancement Of Maxillofacial Ct Data, Murat Balci

Electronic Theses and Dissertations

In computational imaging, data acquired by sampling the same scene or object at different times or from different orientations result in images in different coordinate systems. Registration is a crucial step in order to be able to compare, integrate and fuse the data obtained from different measurements. Tomography is the method of imaging a single plane or slice of an object. A Computed Tomography (CT) scan, also known as a CAT scan (Computed Axial Tomography scan), is a Helical Tomography, which traditionally produces a 2D image of the structures in a thin section of the body. It uses X-ray, which …

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Effects Of Fiber And Lithium On Mechanical Properties Of Concrete Made Fromrecycled Concrete Aggregate, Ashraf Eskander Jan 2006

Effects Of Fiber And Lithium On Mechanical Properties Of Concrete Made Fromrecycled Concrete Aggregate, Ashraf Eskander

Electronic Theses and Dissertations

The growing demand of construction aggregates has raised concern about the availability of natural aggregates. Over two billion tons of natural aggregate are produced each year in the United States and that number is expected to increase to 2.5 billion tons by 2020. This has raised concern about the availability of natural aggregate. Discarding demolished concrete into landfills is a costly solution from an economical and environmental point of view. Many U.S. highway agencies are re-using Recycled Concrete Aggregates (RCA) as construction material. The use of fiber reinforcement in Portland Cement Concrete (PCC) has recently become a popular option in …

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An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed, Salem El-Nimri Jan 2006

An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed, Salem El-Nimri

Electronic Theses and Dissertations

An electromagnetic model for predicting the microwave blackbody emission from the ocean surface under the forcing of strong surface winds in hurricanes is being developed. This ocean emissivity model will be incorporated into a larger radiative transfer model used to infer ocean surface wind speed and rain rate in hurricanes from remotely sensed radiometric brightness temperature. The model development is based on measurements obtained with the Stepped Frequency Microwave Radiometer (SFMR), which routinely flys on the National Oceanic and Atmospheric Administration's hurricane hunter aircraft. This thesis presents the methods used in the wind speed model development and validation results for …

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A Life Cycle Software Quality Model Using Bayesian Belief Networks, Justin Beaver Jan 2006

A Life Cycle Software Quality Model Using Bayesian Belief Networks, Justin Beaver

Electronic Theses and Dissertations

Software practitioners lack a consistent approach to assessing and predicting quality within their products. This research proposes a software quality model that accounts for the influences of development team skill/experience, process maturity, and problem complexity throughout the software engineering life cycle. The model is structured using Bayesian Belief Networks and, unlike previous efforts, uses widely-accepted software engineering standards and in-use industry techniques to quantify the indicators and measures of software quality. Data from 28 software engineering projects was acquired for this study, and was used for validation and comparison of the presented software quality models. Three Bayesian model structures are …

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Wide Viewing Angle Liquid Crystal Displays, Qi Hong Jan 2006

Wide Viewing Angle Liquid Crystal Displays, Qi Hong

Electronic Theses and Dissertations

In this dissertation, novel phase compensation technologies are applied to the designs of wide viewing angle and high transmittance liquid crystal displays. First, a design of wide viewing angle liquid crystal displays utilizing crossed linear polarizers is proposed. The designed multi-domain vertical-alignment liquid crystal display predicts superb contrast ratio over wide viewing angles. Next, to increase the bright state transmittance while maintain the high contrast. Finally, to reduce the cost and improve the applicability of the broadband and wide-view circular polarizer, the device configuration of the broadband and wide-view circular polarizer is significantly simplified by the application of biaxial compensation …

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On-Chip Spiral Inductor/Transformer Design And Modeling For Rf Applications, Ji Chen Jan 2006

On-Chip Spiral Inductor/Transformer Design And Modeling For Rf Applications, Ji Chen

Electronic Theses and Dissertations

Passive components are indispensable in the design and development of microchips for high-frequency applications. Inductors in particular are used frequently in radio frequency (RF) IC's such as low-noise amplifiers and oscillators. High performance inductor has become one of the critical components for voltage controlled oscillator (VCO) design, for its quality factor (Q) value directly affects the VCO phase noise. The optimization of inductor layout can improve its performance, but the improvement is limited by selected technology. Inductor performance is bounded by the thin routing metal and small distance from lossy substrate. On the other hand, the in-accurate inductor modeling further …

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Design, Analysis And Implementation Of Orthogonal Frequency Coding In Saw Devices Used For Spread Spectrum Tags And Sensors, Derek Puccio Jan 2006

Design, Analysis And Implementation Of Orthogonal Frequency Coding In Saw Devices Used For Spread Spectrum Tags And Sensors, Derek Puccio

Electronic Theses and Dissertations

SAW based sensors can offer wireless, passive operation in numerous environments and various device embodiments are employed for retrieval of the sensed data information. Single sensor systems can typically use a single carrier frequency and a simple device embodiment, since tagging is not required. In a multi-sensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This dissertation presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. OFC offers all advantages inherent to spread spectrum communications including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown …

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A Real Option Strategic Scorecard Decision Framework For It Project Selection, Cesar Munoz Jan 2006

A Real Option Strategic Scorecard Decision Framework For It Project Selection, Cesar Munoz

Electronic Theses and Dissertations

The problem of project selection is of significant importance in management of information systems. Almost $2 trillion is spent worldwide every year on IT projects, with over $600 billion spent in the US alone. Traditionally, managers have being using the classical net present value (NPV) method in conjunction with multicriteria scoring models for ROI analysis and selection of IT project investments The multicriteria models use ad-hoc evaluation criteria to assign priority weights and then rate the alternatives against each criterion. These models have two limitations. First, the criteria and weights are based on subjective judgments, allowing the introduction of politics …

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Safety Effects Of Traffic Signal Installations On State Road Intersections In Northeast Florida, Christopher Ledew Jan 2006

Safety Effects Of Traffic Signal Installations On State Road Intersections In Northeast Florida, Christopher Ledew

Electronic Theses and Dissertations

The purpose of this thesis is to explore how the installations of traffic signals affect crash experience at intersections, to identify those factors which help predict crashes after a signal is installed, and to develop a crash prediction model. It is the intent of this thesis to supplement the Manual on Uniform Traffic Control Devices Signal Warrant procedure and aid the traffic engineer in the signal installation decision making process. Crash data, as well as operational and geometric factors were examined for 32 state road intersections in the northeast Florida area before and after signal installation. Signal warrant studies were …

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Algorithms For Discovering Communities In Complex Networks, Hemant Balakrishnan Jan 2006

Algorithms For Discovering Communities In Complex Networks, Hemant Balakrishnan

Electronic Theses and Dissertations

It has been observed that real-world random networks like the WWW, Internet, social networks, citation networks, etc., organize themselves into closely-knit groups that are locally dense and globally sparse. These closely-knit groups are termed communities. Nodes within a community are similar in some aspect. For example in a WWW network, communities might consist of web pages that share similar contents. Mining these communities facilitates better understanding of their evolution and topology, and is of great theoretical and commercial significance. Community related research has focused on two main problems: community discovery and community identification. Community discovery is the problem of extracting …

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Wavelets In Real-Time Rendering, Weifeng Sun Jan 2006

Wavelets In Real-Time Rendering, Weifeng Sun

Electronic Theses and Dissertations

Interactively simulating visual appearance of natural objects under natural illumination is a fundamental problem in computer graphics. 3D computer games, geometry modeling, training and simulation, electronic commerce, visualization, lighting design, digital libraries, geographical information systems, economic and medical image processing are typical candidate applications. Recent advances in graphics hardware have enabled real-time rasterization of complex scenes under artificial lighting environment. Meanwhile, pre-computation based soft shadow algorithms are proven effective under low-frequency lighting environment. Under the most practical yet popular all-frequency natural lighting environment, however, real-time rendering of dynamic scenes still remains a challenging problem. In this dissertation, we propose a …

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Synthesis Of Self-Resetting Stage Logic Pipelines, Rashad Oreifej Jan 2006

Synthesis Of Self-Resetting Stage Logic Pipelines, Rashad Oreifej

Electronic Theses and Dissertations

As designers began to pack multi-million transistors onto a single chip, their reliance on a global clocking signal to orchestrate the operations of the chip has started to face almost insurmountable difficulties. As a result, designers started to explore clockless circuits to avoid the global clocking problem. Recently, self-resetting circuits implemented in dynamic logic families have been proposed as viable clockless alternatives. While these circuits can produce excellent performances, they display serious limitations in terms of area cost and power consumption. A middle-of-the-road alternative, which can provide a good performance and avoid the limitations seen in dynamic self-resetting circuits, would …

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Coupling Of Hydrodynamic And Wave Models For Storm Tide Simulations: A Case Study For Hurricane Floyd (1999), Yuji Funakoshi Jan 2006

Coupling Of Hydrodynamic And Wave Models For Storm Tide Simulations: A Case Study For Hurricane Floyd (1999), Yuji Funakoshi

Electronic Theses and Dissertations

This dissertation presents the development of a two-dimensional St. Johns River model and the coupling of hydrodynamic and wave models for the simulation of storm tides. The hydrodynamic model employed for calculating tides and surges is ADCIRC-2DDI (ADvanced CIRCulation Model for Shelves, Coasts and Estuaries, Two-Dimensional Depth Integrated) developed by Luettich et al. (1992). The finite element based model solves the fully nonlinear shallow water equations in the generalized wave continuity form. Hydrodynamic applications are operated with the following forcings: 1) astronomical tides, 2) inflows from tributaries, 3) meteorological effects (winds and pressure), and 4) waves (wind-induced waves). The wave …

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A Multi-View Framework For Defining The Services Supply Chain Using Object Oriented Methodology, James Barnard Jan 2006

A Multi-View Framework For Defining The Services Supply Chain Using Object Oriented Methodology, James Barnard

Electronic Theses and Dissertations

Supply-chain management is the practice combining theory from logistics, operations management, production management and inventory control. Therefore, it is often associated exclusively with manufacturing or materials management industries. Application of supply-chain management to other industries often results in implementations that do not satisfy the needs of the involved enterprises. To improve the implementation of supply-chain solutions outside of the materials management and manufacturing industries there is a need for industry specific standards. One industry sector in need of a standard is the services industry. The current problem facing the services sector is the inability to adapt current frameworks to the …

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Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems, Matthew Rhodes Jan 2006

Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems, Matthew Rhodes

Electronic Theses and Dissertations

Laser tracking systems are an important aspect of the NASA space program, in particular for conducting research in relation to satellites and space port launch vehicles. Often, launches are conducted at remote sites which require all of the test equipment, including the laser tracking systems, to be portable. Portable systems are more susceptible to environmental disturbances which affect the overall tracking resolution, and consequently, the resolution of any other experimental data being collected at any given time. This research characterizes the optical coupling between two systems in a Mobile Experimental Laser Tracking system and evaluates several control solutions to minimize …

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Developing Microscopic Toll Plaza Model Using Paramics, Nezamuddin Nezamuddin Jan 2006

Developing Microscopic Toll Plaza Model Using Paramics, Nezamuddin Nezamuddin

Electronic Theses and Dissertations

Simulation modeling is the most cost-effective way of studying real life transportation problems, either existing or anticipated, without disturbing the balance of the transportation system. There is a vast suite of simulation models available in market, ready to choose from macroscopic, mesoscopic, or microscopic in nature, to study different transportation system elements like freeways, highways, signalized and un-signalized intersections. However, most of these network simulation models, like PARAMICS, VISSIM, CORSIM … etc, do not come readily available with built in toll plaza models. On the other hand, many researchers have independently developed toll plaza models, which can only model an isolated …

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Bench Scale Analysis Of Experimental Fouling-Resistent Low Pressure Reverse Osmosis Membranes Using High Organic Surface Water And Synthetic Colloidal Water, Matthew Doan Jan 2006

Bench Scale Analysis Of Experimental Fouling-Resistent Low Pressure Reverse Osmosis Membranes Using High Organic Surface Water And Synthetic Colloidal Water, Matthew Doan

Electronic Theses and Dissertations

The utilization of membrane treatment for the production of potable water has become more prevalent in today's industry. As drinking water regulations become more stringent this trend is expected to continue. Widespread use is also a result of membrane treatment being the best available treatment in many cases. While membrane treatment is a proven technology that can produce a consistently superior product to conventional treatment methods, membrane fouling and concentrate disposal are issues that drive up the cost of membrane treatment and can effectively eliminate it from consideration as a treatment alternative. This research focused on membrane fouling. A series …

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