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USF Tampa Graduate Theses and Dissertations

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Evaluating The Reliability Of Continuous Resistivity Profiling To Detect Submarine Groundwater Discharge In A Shallow Marine Environment: Sarasota Bay, Florida, Arnell Harrison Jan 2006

Evaluating The Reliability Of Continuous Resistivity Profiling To Detect Submarine Groundwater Discharge In A Shallow Marine Environment: Sarasota Bay, Florida, Arnell Harrison

USF Tampa Graduate Theses and Dissertations

Submarine groundwater discharge (SGD) can be an important pathway for nutrients entering coastal systems. However SGD flow paths can be difficult to identify and flow volumes difficult to quantify. This study assesses whether geophysical techniques are potentially cost effective methods for detecting the presence or lack of SGD within an estuary environment found in Sarasota Bay, Florida. In this area, a rapid increase in urbanization has led to increased nitrogen loading into the bay, with some 10% of this loading attributed to SGD. Discharging groundwater is expected to be fresher and hence higher resistivity, than "background" surface waters. Thus resistivity …

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Gold Mining In A Tropical Rainforest: Mercury Sorption To Soils In The Mining Region Of Arakaka-Matthew's Ridge, Guyana, Joniqua A'Ja Howard Jan 2006

Gold Mining In A Tropical Rainforest: Mercury Sorption To Soils In The Mining Region Of Arakaka-Matthew's Ridge, Guyana, Joniqua A'Ja Howard

USF Tampa Graduate Theses and Dissertations

Gold mining by artisinal (small-medium scale) miners causes an immense amount of damage to the environment (i.e. soil erosion, mobilization of heavy metals, etc.).1, 2 One of the most popular gold mining techniques employed by artisinal miners in Guyana is mercury amalgamation. During the amalgamation process approximately 300 metric tons/yr 11, 12 of mercury is used. Mercury once in the environment can be transported through the air, soil, and water column. It is estimated that 90-99% of total mercury (THg) is associated with the sediment. An understanding of the geochemical conditions that affect the fate of mercury in soils, which …

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Development And Evaluation Of An Inertial Based Pavement Roughness Measuring System, Fengxuan Hu Jan 2006

Development And Evaluation Of An Inertial Based Pavement Roughness Measuring System, Fengxuan Hu

USF Tampa Graduate Theses and Dissertations

Roughness is an important indicator of pavement riding comfort and safety. It is a condition indicator that should be carefully considered when evaluating primary pavements. At the same time, the use of roughness measurements plays a critical role in the pavement management system.There are many devices used for roughness evaluation. The major tools used for road roughness quantify are the road profilers. In the thesis research, in order to obtain useful pavement surface condition data for pavement evaluation, an inertial based pavement roughness measuring system was developed with the combination of modern sensor technology and computer technology. The research will …

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Hollow-Electrode Pulsed Plasma Deposition Of Titanium And Carbon Thin Films, Robert H. Hyde Jan 2006

Hollow-Electrode Pulsed Plasma Deposition Of Titanium And Carbon Thin Films, Robert H. Hyde

USF Tampa Graduate Theses and Dissertations

This thesis presents a study of a pulsed distributed arc plasma deposition method that has been developed to produce highly ionized pulsed plasma plumes of metallic species in the presence of a low-pressure inert or reactive gas glow discharge. A pulse-forming network (PFN) is used to form a transient electrical discharge in a hollow electrode which is triggered by two different methods; a pulsed CO2 laser or a pulsed high voltage glow discharge. With the PFN charged to a voltage of 70 - 100 VDC, current pulses with peak currents up to 3 kA and pulse widths as long 3.7 …

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Kinematics Of Curved Flexible Beam, Saurabh Jagirdar Jan 2006

Kinematics Of Curved Flexible Beam, Saurabh Jagirdar

USF Tampa Graduate Theses and Dissertations

Compliant mechanism theory permits a procedure called rigidbody replacement, in which two or more rigid links of the mechanism are replaced by a compliant flexure with equivalent motion. Methods for designing flexure with equivalent motion to replace rigid links are detailed in Pseudo-Rigid-Body Models (PRBMs). Such models have previously been developed for planar mechanisms. This thesis develops the first PRBM for spherical mechanisms. In formulating this PRBM for a spherical mechanism, we begin by applying displacements are applied to a curved beam that cause it todeflect in a manner consistent with spherical kinematics. The motion of the beam is calculated …

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Tampa’S Lafayette Street Bridge: Building A New South City, Lucy D. Jones Jan 2006

Tampa’S Lafayette Street Bridge: Building A New South City, Lucy D. Jones

USF Tampa Graduate Theses and Dissertations

The late nineteenth and early twentieth century was a time of dynamic social and political change for Tampa, a growing city on Florida's west coast. These changes led Tampa's commercial-civic elite to look beyond the law, the militia, and the church for ways to maintain their sense of order. This thesis illustrates non-violent enforcement of the status quo via public works, specifically bridge construction over the Hillsborough River. Over a period of three decades, three different bridges were built at the same place, at Lafayette Street. Each time the bridge was built or replaced, it was ostensibly for a different …

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Spring Break: Image, Identity, And Consumer Culture In A Florida Rite Of Passage, Meeghan Kane Jan 2006

Spring Break: Image, Identity, And Consumer Culture In A Florida Rite Of Passage, Meeghan Kane

USF Tampa Graduate Theses and Dissertations

This thesis is a social history of spring break, examining the economic and social aspects of this youth culture phenomenon in Florida. Spring break follows the evolution of youth culture's increasingly complex relationship with an expanding consumer culture. I am exploring its many manifestations in music, film, and popular fiction, but also its rebellious expressions in the riots and arrests on Florida's beaches. I intend to focus on the small beach communities that were transformed by spring break, particularly Fort Lauderdale.Spring break in Florida dates back to the late 1920s in Palm Beach. Wealthy New England families spent their winters …

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Investigations Of Fiber Optic Temperature Sensors Based On Yb:Y3Al5O12, Jermaine L. Kennedy Jan 2006

Investigations Of Fiber Optic Temperature Sensors Based On Yb:Y3Al5O12, Jermaine L. Kennedy

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of temperature sensors which employ a fiber-optic probe consisting of single crystal YB3BAlB5BOB12B (YAG) fiber with a phosphor of short length grown directly onto one end using the laser heated pedestal growth method. The response of all the crystalline temperature sensors derives from the temperature-dependent decay time of fluorescence. Yb3+P ions served as the fluorescer, while the addition of various rare-earth codopants (i.e., NdP3+ and ErP3+) with YbP3+ provided an additional path in the form of phonon assisted energy transfer. With the additional nonradiative decay path, the temperature sensors exhibited a more desirable response. A …

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Measurement And Modeling Of Oxides Of Nitrogen From Vehicular Contributors, Kerstin Lesley Kenty Jan 2006

Measurement And Modeling Of Oxides Of Nitrogen From Vehicular Contributors, Kerstin Lesley Kenty

USF Tampa Graduate Theses and Dissertations

The focus of this research was the examination of the emission and transformation of nitrogen oxides emitted from vehicles. Measured data for this experiment were collected from May 1 thru May 31, 2002, and were compared to values modeled with CALINE4. CALINE4 is a photochemical and dispersive model used to predict concentrations of NOX (NO+NO2) from line sources. The measurement campaign was coincident with the Bay Regional Atmospheric Chemistry Experiment (BRACE). An ambient air quality monitoring site was constructed adjacent to Gandy Boulevard, in Tampa, FL. When comparisons of measured and modeled NO and NO2 values were made it was …

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Measuring Social Stressors In Organizations: The Development Of The Interpersonal Conflict In Organizations Scale (Icos), Valentina Bruk Lee Jan 2006

Measuring Social Stressors In Organizations: The Development Of The Interpersonal Conflict In Organizations Scale (Icos), Valentina Bruk Lee

USF Tampa Graduate Theses and Dissertations

Interpersonal conflict in organizations has been recognized as a leading social stressor across occupations with detrimental effects on employee well-being and organizational outcomes. However, reliable and valid measures of conflict are scarce and even the most widely used scales are limited by weaknesses in construct definition. In order to address the need for an improved measurement tool, the 63-item Interpersonal Conflict in Organizations Scale (ICOS) was developed. The ICOS was based on a comprehensive conceptualization of conflict that defines the construct on the basis of three definitional components: disagreement, interference, and negative emotion (Barki & Hartwick, 2004). In addition, the …

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An Evaluation Of A Pedagogical Reform Designed For College Chemistry Teaching With Large Classes, Scott Edwin Lewis Jan 2006

An Evaluation Of A Pedagogical Reform Designed For College Chemistry Teaching With Large Classes, Scott Edwin Lewis

USF Tampa Graduate Theses and Dissertations

This work presents an evaluation of a reform teaching practice, known as peer-led guided inquiry, that combines guided inquiry and cooperative learning for college chemistry teaching. Integral to implementing the reform in a large class (greater than 100 students) was the role of peer leaders, undergraduate students who have successfully completed the target course. These peer leaders facilitated cooperative learning groups during weekly guided inquiry activities in general chemistry. The evaluation, using data collected over a 3-year period, had two main foci: effective teaching and promotion of equity in the classroom. Both of these aims were evaluated using hierarchical linear …

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Evaluation Of The Operational Effects Of U-Turn Movement, Pan Liu Jan 2006

Evaluation Of The Operational Effects Of U-Turn Movement, Pan Liu

USF Tampa Graduate Theses and Dissertations

In Florida, the increased installation of non-traversable medians and directional median opening has produced an increased number of U-turns on multilane highways. Arguments have been advanced by some opponents of median modification projects that the increased numbers of U-turns may result in safety and operational problems on multilane highways. The primary objective of this study is to evaluate the operational effects of U-turn movement on multilane roadways. To achieve this research objective, extensive data were collected. Field measurements were conducted at 40 sites in the Tampa Bay area of Florida to collect traffic operations data. Besides, the crash histories of …

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Explaining Gender Differences In Salary Negotiations, Meisha -Ann Martin Jan 2006

Explaining Gender Differences In Salary Negotiations, Meisha -Ann Martin

USF Tampa Graduate Theses and Dissertations

The current study explores the effects of gender on salary negotiation behaviors and expectancies and the relationship between these variables and starting salary outcomes. College students from a variety of different majors were surveyed prior to and then approximately two to four months after graduation. Though there was no gender difference in final salary or difference between initial and final salary offer, men reported using more aggressive and active salary negotiation behaviors. The results also suggest that men may have felt more empowered in the salary negotiation context. They expected higher salaries than women did, anticipated less discomfort and believed …

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Quantitative Biological Microscopy By Digital Holography, Christopher J. Mann Jan 2006

Quantitative Biological Microscopy By Digital Holography, Christopher J. Mann

USF Tampa Graduate Theses and Dissertations

In this dissertation, improved techniques in digital holography, that have produced high-resolution, high-fidelity images, are discussed. In particular, the angular spectrum method of calculating holographic optical field is noted to have several advantages over the more commonly used Fresnel transformation or Huygens convolution method. It is observed that spurious noise and interference components can be tightly controlled through the analysis and filtering of the angular spectrum. In the angular spectrum method, the reconstruction distance does not have a lower limit, and the off-axis angle between the object and reference waves can be lower than that of the Fresnel requirement, while …

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Analysis Of Acoustic Emission In Cohesionless Soil, Jeyisanker Mathiyaparanam Jan 2006

Analysis Of Acoustic Emission In Cohesionless Soil, Jeyisanker Mathiyaparanam

USF Tampa Graduate Theses and Dissertations

Acoustic emission is a widely used nondestructive technique for identification of structural damage. The AE technique relies on transient energy waves generated by the materials during their failure. As for soils, the basic causes of acoustic emission are the mechanisms which are responsible for shearing of soils. Mobilization of shear strength within a soil itself and the interaction of the soil with the adjacent natural or construction materials are directly related to the level of acoustic emission in soils. It is envisioned that acoustic emission signals in deforming soils can be used as an early warning sign in real time …

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Molecular Simulations Of Pd Based Hydrogen Sensing Materials, Ling Miao Jan 2006

Molecular Simulations Of Pd Based Hydrogen Sensing Materials, Ling Miao

USF Tampa Graduate Theses and Dissertations

Hydrogen sensor technology is a crucial component for safety and many other practical concerns in the hydrogen economy. To achieve a desired sensor performance, proper choice of sensing material is critical, because it directly affects the main features of a sensor, such as response time, sensitivity, and selectivity. Palladium is well-known for its ability to sorb a large amount of hydrogen. Most hydrogen sensors use Pd-based sensing materials. Since hydrogen sensing is based on surface and interfacial interactions between the sensing material and hydrogen molecules, nanomaterials, a group of low dimensional systems with large surface to volume ratio, have become …

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Goal Conflicts, Self-Regulation, And Course Completion: A Comparison Of Web-Based Learners To Traditional Classroom Learners, Barbara Moore Jan 2006

Goal Conflicts, Self-Regulation, And Course Completion: A Comparison Of Web-Based Learners To Traditional Classroom Learners, Barbara Moore

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to examine the goal conflicts, self-regulation, and course completion of post-secondary learners and to compare these factors in distance and traditional learners. Participants completed a self-report survey given on-line to those who had Internet access and administered in paper format to students in traditional classrooms. Procrastination, socializing, and employment were the most common goal conflicts reported by participants. Significantly more web-based students than traditional students were employed and were employed more average hours. Web-based students also had more children under the age of 12 than did traditional students. A significantly greater percentage of web-based …

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Regression Approach To Software Reliability Models, Abdelelah M. Mostafa Jan 2006

Regression Approach To Software Reliability Models, Abdelelah M. Mostafa

USF Tampa Graduate Theses and Dissertations

Many software reliability growth models have beenanalyzed for measuring the growth of software reliability. In this dissertation, regression methods are explored to study software reliability models. First, two parametric linear models are proposed and analyzed, the simple linear regression and transformed linearregression corresponding to a power law process. Some software failure data sets do not follow the linear pattern. Analysis of popular real life data showed that these contain outliers andleverage values. Linear regression methods based on least squares are sensitive to outliers and leverage values. Even though the parametric regression methods give good results in terms of error measurement …

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Generalized Non-Dimensional Depth-Discharge Rating Curves Tested On Florida Streamflow, Auristela Mueses-Pã©Rez Jan 2006

Generalized Non-Dimensional Depth-Discharge Rating Curves Tested On Florida Streamflow, Auristela Mueses-Pã©Rez

USF Tampa Graduate Theses and Dissertations

A generalized non-dimensional mathematical expression has been developed to describe the rating relation of depth and discharge for intermediate and high streamflow of natural and controlled streams. The expressions have been tested against observations from forty-three stations in West-Central Florida. The intermediate-flow region model has also been validated using data from thirty additional stations in the study area. The proposed model for the intermediate flow is a log-linear equation with zero intercept and the proposed model for the high-flow region is a log-linear equation with a variable intercept. The models are normalized by the depth and discharge values at 10 …

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A Design Of Experiments Study Of Procedure For Assembling Bascule Bridge Fulcrum, Cuong Q. Nguyen Jan 2006

A Design Of Experiments Study Of Procedure For Assembling Bascule Bridge Fulcrum, Cuong Q. Nguyen

USF Tampa Graduate Theses and Dissertations

A bascule bridge is a type of movable bridge that can be opened or closed to facilitate the movement of water-borne traffic such as ships and yachts. Trunnion-Hub-Girder (THG) assembly plays a role as a fulcrum in the bascule bridge. To make the fulcrum, the trunnion is shrink-fitted into the hub, and then the trunnion-hub assembly is shrink-fitted into the girder. Hundreds of thousands of dollars could be lost due to failures during this step. Crack formations in the hubs of various Florida bascule bridges during assembly led the Florida Department of Transportation to commission a project with USF professors …

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The Information Technology Professional’S Psychological Contract Viewed Through Their Employment Arrangement And The Relationship To Organizational Behaviors, Sandra Kay Newton Jan 2006

The Information Technology Professional’S Psychological Contract Viewed Through Their Employment Arrangement And The Relationship To Organizational Behaviors, Sandra Kay Newton

USF Tampa Graduate Theses and Dissertations

Information technology (IT) professionals are continually placed in diverse employment arrangements as organizations continually look for ways to cut costs, enhance performance and maximize organizational goals. Organizations are using strategies beyond hiring permanent employees to achieve objectives in alternative sourcing. Even though the cost differential is positive when employing non-permanent individuals instead of permanent employees, little is known about the effects on the IT professional.This field study was designed to test the effects of employment arrangements on the IT professional's psychological contract and the effects of the level of fulfillment of their psychological contract on their organizational citizenship and innovative …

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Investigating The Fouling Behavior Of Reverse Osmosis Membranes Under Different Operating Conditions, Dhananjaya P. Niriella Jan 2006

Investigating The Fouling Behavior Of Reverse Osmosis Membranes Under Different Operating Conditions, Dhananjaya P. Niriella

USF Tampa Graduate Theses and Dissertations

This dissertation describes the investigation of the fouling of a reverse osmosis membrane under different operating conditions. A mass transfer model to predict the permeate flux decline is defined. These studies used kaolin clay and bentonite clay as the fouling particles. As the membranes, thin film Low fouling Composite 1 polyamide reverse osmosis flat sheet membranes were used. Baseline experiments using only kaolin in D.I. water were conducted. At an operating pressure of approximately 1,380 kPa, no flux decline was observed. These results established the effects of a membrane-particle interaction. For the fouling experiments with kaolin clay, experiments show a …

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Measurement Of Nerve Growth Factor In Induced Sputum And Exhaled Breath Condensate, Victor Maduabuchi Nwiloh Jan 2006

Measurement Of Nerve Growth Factor In Induced Sputum And Exhaled Breath Condensate, Victor Maduabuchi Nwiloh

USF Tampa Graduate Theses and Dissertations

Several tests are available for evaluation of respiratory disorders but most of them are invasive and associated with some risk or patient discomfort. Examples include bronchoscopy (bronchoalveolar lavage, BAL) [1], venopuncture [2] and sputum induction [3]. Noninvasive sampling of nongaseous substances contained in expired air, collected as exhaled breath condensate (EBC) has been used to detect inflammatory markers and by-products including nitric oxide and arachidonic acid metabolites and proteins [4]. Nerve growth factor (NGF) is a protein that has been implicated in neurogenic airway inflammation and this pilot study aimed to develop a non-invasive approach for evaluation of allergic airway …

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Coral Reef Habitat Change And Water Clarity Assessment (1984-2002) For The Florida Keys National Marine Sanctuary Using Landsat Satellite Data, David A. Palandro Jan 2006

Coral Reef Habitat Change And Water Clarity Assessment (1984-2002) For The Florida Keys National Marine Sanctuary Using Landsat Satellite Data, David A. Palandro

USF Tampa Graduate Theses and Dissertations

The decline of coral reef habitats has been witnessed on a global scale, with some of the most dramatic decline occurring in the florida keys. as remote sensing can provide a synoptic view of coral reef ecosystems, 28 landsat images (1984-2002) were utilized to study water clarity and habitat change. first, the data were used to derive the diffuse attenuation coefficient (kd, m-1), a measure of water clarity, for 29 sites throughout the florida keys national marine sanctuary (fknms). landsat-derived kd values from bands 1 (blue) and 2 (green) provided useful information for 26 of 29 sites, whereas band 3 …

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Group Fission-Fusion Dynamics And Communication In The Bottlenose Dolphin (Tursiops Truncatus), Ester Quintana-Rizzo Jan 2006

Group Fission-Fusion Dynamics And Communication In The Bottlenose Dolphin (Tursiops Truncatus), Ester Quintana-Rizzo

USF Tampa Graduate Theses and Dissertations

The bottlenose dolphin exhibits a fission-fusion social structure characterized by temporary associations lasting from minutes to hours. Although social structure has been described for some dolphin communities, the selective pressures affecting fission-fusion patterns and their consequences on dolphin communication are not well understood. The goals of the present study were three-fold: 1) to quantify the rate with which fission-fusion occurred and identify the selective pressures influencing an individual's decision to leave and join a temporary group; 2) to examine the communication signals produced during temporary separations; and 3) to estimate the distances over which dolphins could remain in acoustic contact …

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Estimation Of Evapotranspiration Using Continuous Soil Moisture Measurement, Mandana Seyed Rahgozar Jan 2006

Estimation Of Evapotranspiration Using Continuous Soil Moisture Measurement, Mandana Seyed Rahgozar

USF Tampa Graduate Theses and Dissertations

A new methodology is proposed for estimation of evapotranspiration (ET) flux at small spatial and temporal scales. The method involves simultaneous measurement of soil moisture (SM) profiles and water table heads along transects flow paths. The method has been applied in a shallow water table field site in West-Central Florida for data collected from January 2002 through June 2004. Capacitance shift type moisture sensors were used for this research, placed at variable depth intervals starting at approximately 4 in. (10 cm) below land surface and extending well below the seasonal low water table depth of 59 in. (1.5 m). Vegetation …

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A Study On The Calibration And Accuracy Of The One-Step Tdr Method, Brian David Runkles Jan 2006

A Study On The Calibration And Accuracy Of The One-Step Tdr Method, Brian David Runkles

USF Tampa Graduate Theses and Dissertations

Traditional in-situ soil compaction monitoring methods are often limited in their application, thus quality control of compacted fills and roadway embankments remains a challenging problem. As a result, new methods are being developed to more accurately measure in-situ compaction parameters. Time domain reflectometry (TDR) is one such method. Several advances have been made over the past few years to further the use of TDR technology in water content and density measurement of compacted fill. The one-step method relies on the measurement of the apparent dielectric constant in conjunction with the bulk electrical conductivity, and correlates them through two soil-specific constants, …

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Zeolite Synthesis From Municipal Solid Waste Ash Using Fusion And Hydrothermal Treatment, Maysson Sallam Jan 2006

Zeolite Synthesis From Municipal Solid Waste Ash Using Fusion And Hydrothermal Treatment, Maysson Sallam

USF Tampa Graduate Theses and Dissertations

This dissertation investigates the possibility of producing zeolites from municipal solid waste ash, MSW ash, by using hydrothermal treatment alone and by introducing fusion at 550 °C prior to hydrothermal treatment. The study was performed at different treatment conditions where silica/aluminum ratio of 13.9 and 2.5, hydroxide concentrations of 1.5N, 2.5N and 3.5N, temperatures at 100°C and 60 °C and time at 6, 24 and 72 hours were the major variables used to study zeolites synthesis process. The possibility of forming zeolites A, P1 and X was of particular interest in the present study. Factors, mechanism and modeling of zeolite …

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Using Fuzzy Logic To Enhance Control Performance Of Sliding Mode Control And Dynamic Matrix Control, Edinzo J. Iglesias Sanchez Jan 2006

Using Fuzzy Logic To Enhance Control Performance Of Sliding Mode Control And Dynamic Matrix Control, Edinzo J. Iglesias Sanchez

USF Tampa Graduate Theses and Dissertations

Two application applications of Fuzzy Logic to improve the performance of two controllers are presented. The first application takes a Sliding Mode Controller designed for chemical process to reject disturbances. A fuzzy element is added to the sliding surface to improve the controller performance when set point change affects the control loop; especially for process showing highly nonlinear behavior. This fuzzy element, , is calculated by means of a set of fuzzy rules designed based on expert knowledge and experience. The addition of improved the controller response because accelerate or smooth the controller as the control loop requires. The Fuzzy …

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Assessment Of Biogeochemical Deposits In Landfill Leachate Drainage Systems Phase Ii, Abdul R. Mulla Saleh Jan 2006

Assessment Of Biogeochemical Deposits In Landfill Leachate Drainage Systems Phase Ii, Abdul R. Mulla Saleh

USF Tampa Graduate Theses and Dissertations

Land disposal of solid waste is a vital component of any solid waste management system. Design, operation and closure of municipal solid waste (MSW) landfills are required by regulations to control leachate and gases generated during the life, closure,and post-closure of the facility. Clogging of leachate drainage and removal systems in landfills is a common phenomenon and has been acknowledged in several landfills throughout the United States and abroad. This project was conducted in two phases. Phase I was completed in February of 2005 and Phase II was completed in August of 2006. Leachate characteristics data obtained in Phase I …

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