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2009

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The Design Of An Ic Half Precision Floating Point Arithmetic Logic Unit, Balaji Kannan Dec 2009

The Design Of An Ic Half Precision Floating Point Arithmetic Logic Unit, Balaji Kannan

All Theses

A 16 bit floating point (FP) Arithmetic Logic Unit (ALU) was designed and implemented in 0.35µm CMOS technology. Typical uses of the 16 bit FP ALU include graphics processors and embedded multimedia applications.
The ALU of the modern microprocessors use a fused multiply add (FMA) design technique. An advantage of the FMA is to remove the need for a comparator which is required for a normal FP adder. The FMA consists of a multiplier, shifters, adders and rounding circuit. A fast multiplier based on the Wallace tree configuration was designed. The number of partial products was greatly reduced by the …

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A Particle Swarm Optimization Using Random Keys For Flexible Flow Shop Scheduling Problem With Sequence Dependent Setup Times, Vinodh Sankaran Dec 2009

A Particle Swarm Optimization Using Random Keys For Flexible Flow Shop Scheduling Problem With Sequence Dependent Setup Times, Vinodh Sankaran

All Theses

In this research, a particle swarm optimization algorithm (PSO) using random keys is developed to schedule flexible flow lines with sequence dependent setup times to minimize makespan. The flexible flow line scheduling problem is a branch of production scheduling and is found in industries such as printed circuit board and automobile manufacturing. It is well known that this problem is NP-hard. For this reason, we approach the problem by implementing a particle swarm optimization (PSO), a metaheuristic which is inspired by the motion of a flock of birds or a school of fish searching for food. The proposed PSO has …

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Effect Of Oscillating And Static Retort Thermal Processing Technology Using An Institutional Size Pouch, Judith Trevino Dec 2009

Effect Of Oscillating And Static Retort Thermal Processing Technology Using An Institutional Size Pouch, Judith Trevino

All Theses

The effects of oscillating and static retort thermal processing on heat penetration using an institutional size pouch were evaluated. A literature review of general information on retort thermal processing, process modes, processing mediums, retort pouches and starch was presented.
Frigex-W starch (National Starch Food Innovation) and water mixtures were prepared at three different concentrations (1%, 3% and 5%). Five replications of starch and water mixtures were processed using water spray as the processing medium in institutional size retort pouches (29.2 cm. x 38.1 cm.) using both oscillating and static processing modes.
Viscosity (by Brookfield viscometer and Bostwick consistometer), residual air …

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Principal Component Thermography For Steady Thermal Perturbation Scenarios, Rohit Parvataneni Dec 2009

Principal Component Thermography For Steady Thermal Perturbation Scenarios, Rohit Parvataneni

All Theses

The work focuses on the qualitative enhancement of Thermographic Inspection data using Principal Component Analysis technique. A new processing tool named Economical Singular Value Decomposition (SVD) is proposed for analyzing the infrared image sequences acquired from the test specimen.
Experiments are carried out on test sample using thermal excitation modalities such as flash, halogen and induction to create temperature variations. The infrared (IR) image sequence containing the information about the sample is captured using IR cameras. The acquired IR image sequences are processed using the proposed Economical SVD which projects the matrix of raw pixel values of image sequence into …

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Neomycin Enhances Glutaraldehyde Crosslinking And Glycosaminoglycan Stability In Bioprosthetic Heart Valves, Vincent Friebe Dec 2009

Neomycin Enhances Glutaraldehyde Crosslinking And Glycosaminoglycan Stability In Bioprosthetic Heart Valves, Vincent Friebe

All Theses

The native heart valve will open and close an astonishing 3 billion times in the average lifetime, implicating immense biomechanical ramifications that necessitate near-flawless structure and functional behavior. Deviations from this idyllic function as a result of heart valve disease (HVD) affect millions of individuals worldwide and result in over 275,000 heart valve replacements worldwide every year. Glutaraldehyde (GLUT) cross-linked porcine aortic heart valves, a common type of bioprosthetic heart valve (BHV), are used frequently in these valve replacement surgeries. The native valve leaflets entail a tri-composite design of type I collagen, elastin and glycosaminoglycans (GAGs), each of which are …

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Modeling The Cooling Phase Of The Lens Molding Process, Saravanan Kannan Dec 2009

Modeling The Cooling Phase Of The Lens Molding Process, Saravanan Kannan

All Theses

The lens molding process is a relatively new technique used to manufacture lenses, in particular, high precision aspheric lenses. In order to achieve the desired size and shape of the lens, the cooling process after pressing must be controlled precisely because of the time and temperature dependent viscoelastic behavior of glass near and below the molding temperature. This thesis gives a detailed description of a three-dimensional computational model for analyzing the cooling phase of the lens molding process. Conduction, convection and radiation are considered in the model by coupling a computational fluid dynamics analysis of the flow of nitrogen through …

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Interactive Perception For Cluttered Environments, Robert Willimon Dec 2009

Interactive Perception For Cluttered Environments, Robert Willimon

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Robotics research tends to focus upon either non-contact sensing or machine manipulation, but not both. This paper explores the benefits of combining the two by addressing the problem of extracting and classifying unknown objects within a cluttered environment, such as found in recycling and service robot applications. In the proposed approach, a pile of objects lies on a flat background, and the goal of the robot is to sift through the pile and classify each object so that it can be studied further. One object should be removed at a time with minimal disturbance to the other objects. We propose …

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Comparing Problem-Based Learning And Lecture As Methods To Teach Whole-Systems Design To Engineering Students, Michael Dukes Dec 2009

Comparing Problem-Based Learning And Lecture As Methods To Teach Whole-Systems Design To Engineering Students, Michael Dukes

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The objective of this research is to compare problem-based learning and lecture as methods to teach whole-systems design to engineering students. A case study, Appendix A, exemplifying successful whole-systems design was developed and written by the author in partnership with the Rocky Mountain Institute. Concepts to be tested were then determined, and a questionnaire was developed to test students' preconceptions. A control group of students was taught using traditional lecture methods, and a sample group of students was taught using problem-based learning methods. After several weeks, the students were given the same questionnaire as prior to the instruction, and the …

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Light Beaming From A Single Subwavelength Metal Slit, Pengyu Chen Dec 2009

Light Beaming From A Single Subwavelength Metal Slit, Pengyu Chen

All Theses

In this thesis, light transmission through a single sub-wavelength slit in a silver thin film with periodic gratings at the exit side of the slit has been studied in both the visible and mid-infrared wavelength ranges.
In the visible wavelength range, we first investigate the enhancement of plasmonic light beaming efficiency by near field resonance in a subwavelength metallic slit-groove beaming structure. We show that by varying the film thickness and the separation distance of the beaming grating, the intensity of the near field can be greatly enhanced by resonance, which leads to the increase of the beaming efficiency. Moreover, …

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A Logistic Regression Model To Predict Incident Severity Using The Human Factors Analysis And Classification System, Hrishikesh Kavade Dec 2009

A Logistic Regression Model To Predict Incident Severity Using The Human Factors Analysis And Classification System, Hrishikesh Kavade

All Theses

The Human Factors Analysis and Classification System (HFACS) is used to help identify causal factors that lead to human error. The framework has been used in a variety of industries to identify leading contributing factors of unsafe events, such as accidents, incidents and near misses. While traditional application of the HFACS framework to safety outcomes has allowed evaluators to identify leading causal issues based on frequency, little has been done to gain a more comprehensive view of the system's total risk. This work utilizes the concept of event severity along with the HFACS framework to help better identify target areas …

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Charging Kinetics Of Electric Double Layer Capacitors, Clint Cagle Dec 2009

Charging Kinetics Of Electric Double Layer Capacitors, Clint Cagle

All Theses

A recent increase in the popularity of EDLCs and AC-EOF has necessitated a deeper understanding of the structure and charging kinetics of electrical double layers (EDLs) at electrode-electrolyte interfaces. Here, the charging kinetics of EDLs in nanoscale EDLCs is studied by a circuit model, a Poisson-Nernst-Planck (PNP) mo del, and molecular dynamics (MD) simulations. The results of the MD simulations demonstrate a linear charging behavior of EDLs near planar electrodes for both aqueous and organic electrolytes at charging below 90% and time larger than tens of picoseconds. Additionally, we will show that the circuit and PNP models are capable of …

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Investigation Of The Thermoelectric Behavior And Structure Formation Of (Pbte/Agsbte2)-Silver Chalcogenide Mixtures, Yisha Wang Dec 2009

Investigation Of The Thermoelectric Behavior And Structure Formation Of (Pbte/Agsbte2)-Silver Chalcogenide Mixtures, Yisha Wang

All Theses

Sustainable energy research is currently on the forefront of scientific exploration and energy conservation and the development of new energy production techniques are both crucial for our long lasting stable future. Accordingly, thermoelectric materials will be a significant energy conservation and production source. The state-of -the-art thermoelectric materials can be used to collect the wasted heat and converted to power, which is the future for the green power generation.
PbTe is considered a state-of-the-art thermoelectric material, which has been extensively studied. It forms in the NaCl structure and it is a semiconductor with a room temperature gap value of 0.29 …

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Deviant, Courtney Richards Dec 2009

Deviant, Courtney Richards

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ABSTRACT
I create portraits and self-portraits that explore the dualities of the western human condition, namely the deviant and the ideal, the refined and the unrefined, and the perfect and the flawed. Drawing on personal experiences with people considered outsiders or social deviants, I construct figures that embody the conflicting ideas inherent in these dualities. I explore these conflicts in drawings that are constructed with marks and shapes that are both basic and refined, and in photographs that use analytic documentation to describe social turmoil. I reference artists both contemporary and historical, such as Egon Schiele, Robert Longo, Kathe Kollwitz, …

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Filtering Noise Caused By Sensor Selection For An Ultra-Wide Band Position Tracking System, Danyan Ganjali Dec 2009

Filtering Noise Caused By Sensor Selection For An Ultra-Wide Band Position Tracking System, Danyan Ganjali

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A filter designed to be optimal for alternating multi-sensor tracking systems is presented. This filter can be used on ultra-wide band position tracking systems such as the Ubisense system. In this thesis, a comprehensive evaluation of the accuracy of the Ubisense tracking system in a multi-room building is given. Then the multi-modality of the noise distribution of such a system is shown. A multi-sensor tracking system is then simulated and a Kalman filter is used to filter the measurements. It is shown that the Kalman filter is not optimal for such a system and the need for a filter that …

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Vehicle-Infrastructure Integration (Vii) Enabled Plug-In Hybrid Electric Vehicles (Phevs) For Traffic And Energy Management, Xueying Kang Dec 2009

Vehicle-Infrastructure Integration (Vii) Enabled Plug-In Hybrid Electric Vehicles (Phevs) For Traffic And Energy Management, Xueying Kang

All Theses

Vehicle Infrastructure Integration (VII) program (also known as IntelliDrive) has proven the potential to improve transportation conditions by enabling the communication between vehicles and infrastructure, which provides a wide range of applications in transportation safety and mobility. Plug-in hybrid electric vehicles (PHEVs) that utilize both electrical and gasoline energy are a commercially viable technology with potential to contribute to both sustainable development and environmental conservation through increased fuel economy and reduced emissions. Considering positive potentials of PHEVs and VII in ITS, a framework that integrates PHEVs with VII technology was created in this research utilizing vehicle-to-vehicle and vehicle-to-infrastructure communications for …

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Risk Assessment Of Bird Aircraft Strike Hazard For Grassland Birds At The Mcentire Air National Guard Station, Eastover, South Carolina, Marla Hamilton Dec 2009

Risk Assessment Of Bird Aircraft Strike Hazard For Grassland Birds At The Mcentire Air National Guard Station, Eastover, South Carolina, Marla Hamilton

All Theses

ABSTRACT
There are strict regulations surrounding vegetation management at military airfields for the purpose of reducing Bird Aircraft Strike Hazards (B.A.S.H.). At military installations vegetation heights are set between 17 to 38 cm to discourage the use of animal species such as flocking birds, soarers (e.g. raptors), large wading birds (e.g. herons), and waterfowl that create hazards to flying aircraft. Within designated clear zones, managers have typically promoted the growth of non - non-native grasses without much consideration for how these plantings might impact B.A.S.H. potential, bird occupancy, or avian conservation. Grasslands and grassland associated avifauna are among the 'highest …

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Effectiveness Of Team-Building And Teamwork In Real And Virtual Worlds, Rachana Ranade Dec 2009

Effectiveness Of Team-Building And Teamwork In Real And Virtual Worlds, Rachana Ranade

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Given the increasing importance of globalization and collaboration, this research investigates the possibility of performing team-building training for globally dispersed teams using the capabilities of the virtual world Second Life. Three meeting conditions, the 3D virtual world Second Life, a combination of face-to-face and Second Life and face-to-face were evaluated. Thirty randomly assigned 3 person teams performed an ice-breaker session and then a team-building activity in each meeting condition. Four dependent variables were measured: task completion time; quality of task performance; the subjective satisfaction with the process based on group cohesiveness, perception of the process and satisfaction with the outcome; …

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An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi Dec 2009

An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi

All Theses

To meet the increasing demand for monitoring of the physical world, there has been an increase in the development of wireless sensor network applications. The TinyOS platform has emerged as a de facto standard for developing these applications. The platform offers a number of advantages, with its support for concurrency, power-efficient operation, and resource-constrained hardware chief among them. However, the benefits come at a price. Even without the TinyOS platform, the inherent parallel and distributed nature of these applications makes it difficult for developers to reason about program behavior. Further, the TinyOS programming model adopts
asynchronous, split-phase execution semantics. Developers …

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Analysis Of Distributed Denial Of Service Attacks And Countermeasures, Sampada Karandikar Dec 2009

Analysis Of Distributed Denial Of Service Attacks And Countermeasures, Sampada Karandikar

All Theses

Network technology has experienced explosive growth in the past two decades. The vast connectivity of networks all over the world poses monumental risks. The generally accepted philosophy in the security world is that no system or network is completely secure [1] which makes network security a critical concern. The work done in this thesis focuses on Distributed Denial of Service Attacks (DDoS) where legitimate users are prevented from accessing network services. Although a lot of research has been done in this field, these attacks remain one of the most common threats affecting network performance.
One defense against DDoS attacks is …

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Monitoring Co Concentration In Fuel Cells Using Microcantilever Sensors, Tugba Demir Dec 2009

Monitoring Co Concentration In Fuel Cells Using Microcantilever Sensors, Tugba Demir

All Theses

Estimating the concentration of gases including carbon monoxide (CO) in the hydrogen fuel exiting the reformer and entering the fuel cell is imperative. A high concentration of CO can cause fuel-cell catalyst poisoning, which permanently destroys the cell. Current practices call for utilizing expensive and bulky spectral analyzers to achieve this task. In addition to their high cost, these methodologies, undoubtedly, hinder the portability and self-containment of the cell. To overcome these problems and achieve the desired objectives of a portable, self-contained, and real-time measurement module, this thesis presents and experimentally investigates a new enabling technology based on utilizing an …

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Relationships Between Lane Change Performance And Open-Loop Handling Metrics, Robert Powell Dec 2009

Relationships Between Lane Change Performance And Open-Loop Handling Metrics, Robert Powell

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This work deals with the question of relating open-loop handling metrics to driver-in-the-loop performance (closed-loop). The goal is to allow manufacturers to reduce cost and time associated with vehicle handling development. A vehicle model was built in the CarSim environment using kinematics and compliance, geometrical, and flat track tire data. This model was then compared and validated to testing done at Michelin's Laurens Proving Grounds using open-loop handling metrics. The open-loop tests conducted for model validation were an understeer test and swept sine or random steer test. Four commonly used handling metrics (steady state yaw rate gain, yaw rate damping …

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Semantic Search, Anup Sawant Dec 2009

Semantic Search, Anup Sawant

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The thesis describes a Semantic approach towards web search through a stand-alone Java application. An Ontology Web Language(OWL) model is used to build a knowledge database related to different types of Organisms. The goal is to guide the Google web search engine using this OWL model. In the rst approach towards Semantic web search, an inference engine called CLIPS is used and in the second aproach, the Protege-OWL API is used. The thesis goes in detail about the design,
working and comparison of these two approaches. The thesis also deals with design approach for enhancement of the OWL model, once …

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Friction Stir Welding Process And Material Microstructure Evolution Modeling In 2000 And 5000 Series Of Aluminum Alloys, Harshavardhan Yalavarthy Dec 2009

Friction Stir Welding Process And Material Microstructure Evolution Modeling In 2000 And 5000 Series Of Aluminum Alloys, Harshavardhan Yalavarthy

All Theses

Interactions between the rotating and advancing pin-shaped tool (terminated at one end with a circular-cylindrical shoulder) with the clamped welding-plates and the associated material and heat transport during a Friction Stir Welding (FSW) process are studied computationally using a fully-coupled thermo-mechanical finite-element analysis. To surmount potential numerical problems associated with extensive mesh distortions/entanglement, an Arbitrary Lagrangian Eulerian (ALE) formulation was used which enabled adaptive re-meshing (to ensure the continuing presence of a high-quality mesh) while allowing full tracking of the material free surfaces. To demonstrate the utility of the present computational approach, the analysis is applied to the cases of …

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Evaluation Of An Online Intelligent Transportation System (Its) Asset Management System, Tahera Anjuman Dec 2009

Evaluation Of An Online Intelligent Transportation System (Its) Asset Management System, Tahera Anjuman

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Intelligent Transportation System (ITS) enhances the performance of modern transportation systems by improving the reliability of travel times and reducing the risk of collisions and injuries. Recently, many public agencies have expressed a need for an ITS asset management system that will effectively and efficiently meet their requirements of managing associated resources, which often includes technologically sophisticated devices, computer hardware and software, and communications infrastructure. To address this need, the author evaluated different asset management systems for their potential efficacy to support public agencies requirements for an ITS asset management system. These requirements were identified through a nationwide survey of …

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Mechanical And Chemical Characterization Of Biological Composite Structures, Bonnie Zimmerman Dec 2009

Mechanical And Chemical Characterization Of Biological Composite Structures, Bonnie Zimmerman

All Theses

A better understanding of the bioresponse of naturally occurring systems will help
to optimize the engineering of synthetic biomaterials. The aim of this thesis was to
characterize the mechanical and chemical behavior of two distinct biological composite
systems, human teeth and wool fibers. These mechanical and chemical properties were
also studied as a function of natural structure and environmental conditions.
Human teeth are composite systems consisting primarily of hydroxylapatite and
protein. This project investigated how the use of clinical dental treatments and
procedures, such as whitening and etching, affects mechanical properties. Analysis of
nanoindentation with the Oliver-Pharr model provided elastic …

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Gain Guiding In Large-Core Bragg Fibers, Xianyu Ao, Tsing-Hua Her, Lee W. Casperson Dec 2009

Gain Guiding In Large-Core Bragg Fibers, Xianyu Ao, Tsing-Hua Her, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

We theoretically analyze gain guiding in large-core Bragg fibers, to be used for large-mode-area laser amplifiers with single-transverse-mode operation. The signal is gain-guided in a low-index core, whereas the pump is guided by the photonic bandgap of the Bragg cladding to achieve good confinement. The high-index layers in the Bragg cladding are half-wave thick at the signal wavelength in order to eliminate Bragg reflection, reducing the Bragg fiber effectively to a step-index fiber for gain guiding.

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Thermoelastic Behavior Of A Small Bearing Cage, Eric Planting Dec 2009

Thermoelastic Behavior Of A Small Bearing Cage, Eric Planting

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The full field non contact measurement of objects undergoing testing is one of interest for manufacturers of parts which are graded on their longevity. Unfortunately, for homogenous small parts with irregular geometries, such as bearing cages, the solution for testing is typically to use only a FEA model and compliment the testing of the model with simply cyclically loading the sample until failure. To better understand the stresses and behavior of a small object Thermoelasticity can be employed in order to see in a full field technique what stress patterns exist and their correlation to a FEA model.
The FEA …

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Straight Line Braking Performance Of A Road Vehicle With Non Linear Tire Stiffness Formulation, Anup Khekare Dec 2009

Straight Line Braking Performance Of A Road Vehicle With Non Linear Tire Stiffness Formulation, Anup Khekare

All Theses

The capability of a road vehicle equipped with an Anti-Lock Braking System (ABS) to come to a safe stop depends on factors such as dynamic force between tire and road, surface adhesion coefficient, and the vertical profile of the road. When in panic, a driver's reaction is to step hard on the brakes to make the vehicle stop as soon as possible. Although the use of modern technologies such as ABS and Electronic Stability Control (ESC) have reduced the number of accidents significantly, any further improvement in stopping distance would only complement these technologies.
Michelin has undertaken the development of …

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The Classic Muscle Car Era, William Mckinney Dec 2009

The Classic Muscle Car Era, William Mckinney

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Big and bold, loud and brash, mighty and proud, the classic American muscle car is in many ways a reflection of America at a time in history when we were on top of the world and everything seemed to be going our way. This work will examine the classic muscle car era of 1964-1974, including how it started, who helped it along, what cars were involved, how it ended, and what it meant. What the future holds for a car such as a muscle car is also examined.

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Biological Treatment To Remove Color And Toxicity Of Effluent From The Manufacturing Of Navipol Yellow Gr, Larry French Dec 2009

Biological Treatment To Remove Color And Toxicity Of Effluent From The Manufacturing Of Navipol Yellow Gr, Larry French

All Theses

Navipol Yellow GR is an organic solvent azo dye manufactured by Sunbelt Corp. in Rock Hill, SC. The effluent generated from the manufacturing of this dye is highly colored, toxic, and contains trace solvents consisting of mixed xylene isomers and ethyl benzene. Traditional wastewater treatment systems are unable to remove the color and toxicity from the effluent. This study investigated using a sequential anaerobic / aerobic treatment system to decrease color and toxicity of the dye effluent. The anaerobic phase used bacteria cultures of Pseudomonas aeruginosa, Bacillus subtilis, Enterococcus faecalis, or Enterobacter aerogenes to decrease the color of the dye. …

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