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USF Tampa Graduate Theses and Dissertations

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Three Dimensional Finite Element Model For Lesion Correspondence In Breast Imaging, Yan Qiu Nov 2003

Three Dimensional Finite Element Model For Lesion Correspondence In Breast Imaging, Yan Qiu

USF Tampa Graduate Theses and Dissertations

Predicting breast tissue deformation is of great significance in several medical applications such as surgery, biopsy and imaging. In breast surgery, surgeons are often concerned with a specific portion of the breast, e.g., tumor, which must be located accurately beforehand. Also clinically it is important for combining the information provided by images from several modalities or at different times, for the planning and guidance of interventions. Multi-modality imaging of the breast obtained by mammography, MRI and PET is thought to be best achieved through some form of data fusion technique. However, images taken by these various techniques are often obtained …


Workflow Modeling Using Finite Automata, Atul Ravi Khemuka Nov 2003

Workflow Modeling Using Finite Automata, Atul Ravi Khemuka

USF Tampa Graduate Theses and Dissertations

A Workflow is an automation of a business process. In general, it consists of processes and activities, which are represented by well-defined tasks. These include 'Office Automation,' 'Health Care' and service-oriented processes such as 'Online Reservations,' 'Online Bookstores' and 'Insurance Claims,' etc. The entities that execute these tasks are humans, application programs or database management systems. These tasks are related and dependent on one another based on business policies and rules.

With rapid increases in application domains that use workflow management systems, there is a need for a framework that can be used to implement these applications. In particular, it …


Computer-Aided Diagnosis For Mammographic Microcalcification Clusters, Mugdha Tembey Nov 2003

Computer-Aided Diagnosis For Mammographic Microcalcification Clusters, Mugdha Tembey

USF Tampa Graduate Theses and Dissertations

Breast cancer is the second leading cause of cancer deaths among women in the United States and microcalcifications clusters are one of the most important indicators of breast disease. Computer methodologies help in the detection and differentiation between benign and malignant lesions and have the potential to improve radiologists' performance and breast cancer diagnosis significantly.

A Computer-Aided Diagnosis (CAD-Dx) algorithm has been previously developed to assist radiologists in the diagnosis of mammographic clusters of calcifications with the modules: (a) detection of all calcification-like areas, (b) false-positive reduction and segmentation of the detected calcifications, (c) selection of morphological and distributional features …


A Novel Normal-To-Plane Space Efficient Micro Corner Cube Retroreflector With Improved Fill Factor, Rahul Agarwal Nov 2003

A Novel Normal-To-Plane Space Efficient Micro Corner Cube Retroreflector With Improved Fill Factor, Rahul Agarwal

USF Tampa Graduate Theses and Dissertations

A Corner Cube Retro-reflector (CCR) is a device that can be used as transmitters in wireless free space optical communication systems, or remote sensing instruments. A novel approach to fabricate the CCR is developed, where almost 100% of the planar chip area acts as the CCR compared to the maximum of 33% in the prior MEMS CCRs. Unlike the conventional micro machined CCRs that have two planes (mirrors of the CCR) normal to the surface of the wafer, our approach yields all the mirrors within the bulk of the wafer, ensuring very high packing densities and wide acceptance angles. The …


Feasibility And Emissions Of Compression Ignition Engines Fueled With Waste Vegetable Oil, Morgan H. Crawford Nov 2003

Feasibility And Emissions Of Compression Ignition Engines Fueled With Waste Vegetable Oil, Morgan H. Crawford

USF Tampa Graduate Theses and Dissertations

Research and experience has shown that vegetable oil can be processed, by transesterification, into a useable fuel for compression ignition engines. Earlier research examined using straight vegetable oil as a fuel, but found it to cause detrimental engine problems. Trial and error has shown that heating the vegetable oil prior to injection, is a viable option. A diesel vehicle engine was operated for over 188 hours or approximately 7,000 miles, using waste cooking oil as fuel. The longevity of the vehicle engine was limited by an undetermined engine failure.

Using stationary testing, with no engine load and various power settings, …


Design And Development Of A Silicon Carbide Chemical Vapor Deposition Reactor, Matthew T. Smith Nov 2003

Design And Development Of A Silicon Carbide Chemical Vapor Deposition Reactor, Matthew T. Smith

USF Tampa Graduate Theses and Dissertations

The goal of this thesis is to present the design and development of a chemical vapor deposition reactor for the growth of high quality homoepitaxy silicon carbide films for electronic device applications. The work was performed in the Nanomaterials and Nanomanufacturing Research Center at the University of South Florida from 8/2001-5/2003.

Chemical vapor deposition (CVD) is the technique of choice for SiC epitaxial growth. Epitaxial layers are the building blocks for use in various semiconductor device applications. This thesis reports on a SiC epitaxy process where a carrier gas (hydrogen) is saturated with reactive precursors (silane and propane) which are …


Optimizing Cost And Data Entry For Assignment Of Patients To Clinical Trials Using Analytical And Probabilistic Web-Based Agents, Bhavesh Dineshbhai Goswami Nov 2003

Optimizing Cost And Data Entry For Assignment Of Patients To Clinical Trials Using Analytical And Probabilistic Web-Based Agents, Bhavesh Dineshbhai Goswami

USF Tampa Graduate Theses and Dissertations

A clinical trial is defined as a study conducted on a group of patients to determine the effect of a treatment. Assignment of patients to clinical trials is a data and labor intensive task. Usually, medical personnel manually check the eligibility of a patient for a clinical trial based on the patient's medical history and current medical condition. According to studies, most clinical trials are under-enrolled which negatively affects their effectiveness. We have developed web-based agents that can test the eligibility of patients for many clinical trials at once. We have tested various heuristics for optimizing cost and data entry …


Analysis Of Flow In A Spray Nozzle With Emphasis On Exiting Jet Free Surface, Ryan M. Mead Nov 2003

Analysis Of Flow In A Spray Nozzle With Emphasis On Exiting Jet Free Surface, Ryan M. Mead

USF Tampa Graduate Theses and Dissertations

A conical nozzle with two separate inlets within its top plate is analyzed. One of the inlets is in the center of the top plate, which is free to rotate, whereas the other inlet is positioned away from the center. The fluid entering through the outer inlet slot causes the top plate of the nozzle to spin. Several fluids including FC-77, FC-72, FC-87, and Methanol running at different flow rates were investigated to observe the effect that their particular properties have on the geometry of the fluid's free surface exiting the nozzle. Another variation performed was the geometry of the …


Evaluation Of Pile Driving Lead Section, Kadir Uslu Nov 2003

Evaluation Of Pile Driving Lead Section, Kadir Uslu

USF Tampa Graduate Theses and Dissertations

Driving piles constitute a large portion of the high-capacity foundations used today. They transfer structural loads to deep bearing strata when adequate surficial soils are not available. The mechanisms required to install these piles generally consist of a hammer, hammer lead, a crane, and various support rigging.

This study focused on lead sections, specifically, one which was manufactured by Berminghammer Foundation Equipment, Inc. The dimensions and strength of a lead section must be capable of supporting both the pile driving hammer and the longest anticipated pile for a given site. The strength of the section must be capable of withstanding …


Mass Transfer Of Ionic Species In Direct And Reverse Osmosis Processes, Silvana Melania Stefania Ghiu Oct 2003

Mass Transfer Of Ionic Species In Direct And Reverse Osmosis Processes, Silvana Melania Stefania Ghiu

USF Tampa Graduate Theses and Dissertations

This dissertation investigates the importance of diffusional and convective fluxes for salts in reverse osmosis (RO) and nanofiltration (NF) membranes. Moreover, the physical and thermodynamic factors controlling the salt permeability are analyzed. The study utilizes direct osmosis (DO) experiments and RO experiments, the later using both flat sheet and spiral wound membrane configurations. The salts considered are chlorides and acetates of alkali metals and alkaline earth metals.

The equation governing the salt transport in DO experiments is derived and a phenomenon inverse to concentration polarization in RO is observed. The salt permeability in DO is equal to the salt permeability …


Small And Large Signal Modeling Of Mm-Wave Mhemt Devices, William, Clausen Oct 2003

Small And Large Signal Modeling Of Mm-Wave Mhemt Devices, William, Clausen

USF Tampa Graduate Theses and Dissertations

This research effort advances millimeter-wave transistor modeling in a current RF/Microwave circuit simulator (Agilent's Advanced Design System-ADS) for small-signal noise and large signal simulations. The device modeled is a metamorphic High Electron Mobility Transistor (mHEMT) supplied by Raytheon RF components. Because of their structure, these new low noise devices are used in this work to test the abilities to accurately model in the sub 0.5dB noise figure territory and to study model prediction into W-band (75-110 GHz).

New modeling issues discussed in this thesis involve the effects of noise modeling in relation to the small-signal model parameters. The noise modeling …


Fpga-Based Implementation Of Concatenative Speech Synthesis Algorithm, Praveen Kumar Bamini Oct 2003

Fpga-Based Implementation Of Concatenative Speech Synthesis Algorithm, Praveen Kumar Bamini

USF Tampa Graduate Theses and Dissertations

The main aim of a text-to-speech synthesis system is to convert ordinary text into an acoustic signal that is indistinguishable from human speech. This thesis presents an architecture to implement a concatenative speech synthesis algorithm targeted to FPGAs. Many current text-to-speech systems are based on the concatenation of acoustic units of recorded speech. Current concatenative speech synthesizers are capable of producing highly intelligible speech. However, the quality of speech often suffers from discontinuities between the acoustic units, due to contextual differences. This is the easiest method to produce synthetic speech. It concatenates prerecorded acoustic elements and forms a continuous speech …


Crystal Engineering Of Binary Compounds Containing Pharmaceutical Molecules, Leslie Ann Morales Oct 2003

Crystal Engineering Of Binary Compounds Containing Pharmaceutical Molecules, Leslie Ann Morales

USF Tampa Graduate Theses and Dissertations

The synthesis or the interaction between two or more molecules is known as supramolecular chemistry. The concept of supramolecular chemistry can be applied to the design of new pharmaceutical materials affording new compositions of matter with desirable composition, structure and properties.

The design of a two-molecule, or binary, compound using complementary molecules represents an example of an application of crystal engineering. Crystal engineering is the understanding of intermolecular interactions, in the context of crystal packing, in the design of new solid materials. By identifying reliable connectors through molecular recognition or self-assembly, one can build predictable architectures.

The study of supramolecular …


Cvd Growth Of Sic On Novel Si Substrates, Rachael L. Myers Oct 2003

Cvd Growth Of Sic On Novel Si Substrates, Rachael L. Myers

USF Tampa Graduate Theses and Dissertations

Silicon Carbide has been a semiconductor material of interest as a high power and temperature replacement for Silicon (Si) in harsh environments due to the higher thermal conductivity and chemical stability of SiC. The cost, however, to produce this material is quite high. There are also defects in the substrate material (SiC) that penetrate into the active devices layers which are known device killers. Silicon is a material that provides a low cost substrate material for epitaxial growth and does not contain the defects that SiC substrates have. However, the large (~22%) lattice mismatch between Si and SiC creates dislocations …


Force-Directed Instruction Scheduling For Low Power, Prashant Dongale Oct 2003

Force-Directed Instruction Scheduling For Low Power, Prashant Dongale

USF Tampa Graduate Theses and Dissertations

The increasing need for low-power computing devices has led to the efforts to optimize power in all the components of a system. It is possible to achieve significant power optimization at the software level through instruction reordering during the compilation phase. In this thesis, we have designed and implemented a novel instruction scheduling technique, called FD-ISLP, aimed at reducing the software power consumption. In the proposed approach for instruction scheduling, we modify the force-directed scheduling technique used in high-level synthesis of VLSI circuits to derive a latency-constrained algorithm that reorders the instructions in a basic block of assembly code in …


Coge1.5Se1.5 : Structural And Transport Properties Characterization, Randolph Ertenberg Oct 2003

Coge1.5Se1.5 : Structural And Transport Properties Characterization, Randolph Ertenberg

USF Tampa Graduate Theses and Dissertations

Skutterudites have been of great interest for thermoelectric applications over the last ten years. Scientific interest has focused on the unique transport properties Skutterudites possess due to the unique crystal structure. Technical interest has grown since it was discovered that some compounds rival the current best thermoelectric materials. To further the understanding of this material system, and optimize its thermoelectric properties, the synthesis and characterization of polycrystalline n- and ptype CoGe1.5Se1.5 was undertaken. Structural, morphological, chemical, electrical, thermal and magnetic properties were studied. These data are compared to those of the binary Skutterudite CoSb3. The results of this study show …


Energy And Transient Power Minimization During Behavioral Synthesis, Saraju P. Mohanty Oct 2003

Energy And Transient Power Minimization During Behavioral Synthesis, Saraju P. Mohanty

USF Tampa Graduate Theses and Dissertations

The proliferation of portable systems and mobile computing platforms has increased the need for the design of low power consuming integrated circuits. The increase in chip density and clock frequencies due to technology advances has made low power design a critical issue. Low power design is further driven by several other factors such as thermal considerations and environmental concerns. In low-power design for battery driven portable applications, the reduction of peak power, peak power differential, average power and energy are equally important. In this dissertation, we propose a framework for the reduction of these parameters through datapath scheduling at behavioral …


Vector Flow Model In Video Estimation And Effects Of Network Congestion In Low Bit-Rate Compression Standards, Balaji Ramadoss Oct 2003

Vector Flow Model In Video Estimation And Effects Of Network Congestion In Low Bit-Rate Compression Standards, Balaji Ramadoss

USF Tampa Graduate Theses and Dissertations

The use of digitized information is rapidly gaining acceptance in bio-medical applications. Video compression plays an important role in the archiving and transmission of different digital diagnostic modalities. The present scheme of video compression for low bit-rate networks is not suitable for medical video sequences. The instability is the result of block artifacts resulting from the block based DCT coefficient quantization. The possibility of applying deformable motion estimation techniques to make the video compression standard (H.263) more adaptable for bio-medial applications was studied in detail. The study on the network characteristics and the behavior of various congestion control mechanisms was …


Matlab Implementation Of Gsm Traffic Channel, Nikhil Deshpande Oct 2003

Matlab Implementation Of Gsm Traffic Channel, Nikhil Deshpande

USF Tampa Graduate Theses and Dissertations

The GSM platform is a extremely successful wireless technology and an unprecedented story of global achievement. The GSM platform is growing and evolving and offers an expanded and feature-rich voice and data enabling services. General Packet Radio Service, (GPRS), will have a tremendous transmission rate, which will make a significant impact on most of the existing services. Additionally, GPRS stands ready for the introduction of new services as operators and users, both business and private, appreciate the capabilities and potential that GPRS provides. Services such as the Internet, videoconferencing and on-line shopping will be as smooth as talking on the …


Implementation Of An Acoustic Echo Canceller Using Matlab, Srinivasaprasath Raghavendran Oct 2003

Implementation Of An Acoustic Echo Canceller Using Matlab, Srinivasaprasath Raghavendran

USF Tampa Graduate Theses and Dissertations

The rapid growth of technology in recent decades has changed the whole dimension of communications. Today people are more interested in hands-free communication. In such a situation, the use a regular loudspeaker and a high-gain microphone, in place of a telephone receiver, might seem more appropriate. This would allow more than one person to participate in a conversation at the same time such as a teleconference environment. Another advantage is that it would allow the person to have both hands free and to move freely in the room. However, the presence of a large acoustic coupling between the loudspeaker and …


University Copyright Policies For Online Coures: An Evaluative Resource Tool For Unbundling Rights Of Use, Control, And Revenue, Tamara A. Patzer Oct 2003

University Copyright Policies For Online Coures: An Evaluative Resource Tool For Unbundling Rights Of Use, Control, And Revenue, Tamara A. Patzer

USF Tampa Graduate Theses and Dissertations

Who cares about who owns online courses? Nobody, because that is not what the issue is really about. Ownership is an emotional issue, but controlling the rights of a copyrightable work is tangible and logical. The important question to answer is not who owns online courses, but who controls the rights of any copyrightable work. For universities and faculty members, getting over the emotional issues and down to the foundation of what is truly at stake is of major concern. While it is nearly impossible to create qualitative guidelines for copyright policies and/or contracts, it is eminently possible to examine …


High Level Techniques For Leakage Power Estimation Andoptimization In Vlsi Asics, Chandramouli Gopalakrishnan Sep 2003

High Level Techniques For Leakage Power Estimation Andoptimization In Vlsi Asics, Chandramouli Gopalakrishnan

USF Tampa Graduate Theses and Dissertations

As technology scales down and CMOS circuits are powered by lower supply voltages, standby leakage current becomes significant. A behavioral level framework for the synthesis of data-paths with low leakage power is presented. There has been minimal work done on the behavioral synthesis of low leakage datapaths. We present a fast architectural simulator for leakage (FASL) to estimate the leakage power dissipated by a system described hierarchically in VHDL. FASL uses a leakage power model embedded into VHDL leafcells. These leafcells are characterized for leakage accurately using HSPICE. We present results which show that FASL measures leakage power significantly faster …


Dry Sliding Tribological Characteristics Of Hard, Flat Materials With Low Surface Roughness, Subrahmanya Mudhivarthi Sep 2003

Dry Sliding Tribological Characteristics Of Hard, Flat Materials With Low Surface Roughness, Subrahmanya Mudhivarthi

USF Tampa Graduate Theses and Dissertations

This thesis focuses on identifying hard material pairs with low roughness, high coefficient of static friction, high wear resistance and high modulus of elasticity, suitable for sliding in dry friction conditions under a normal load. A wide range of materials including various steels, various coatings on tool steels deposited by various deposition techniques and different ceramics were examined and considered for tribological testing. Procedures and sequences were developed for conducting tribology tests on the material pairs. High endurance - low cycle tests were conducted and based on the performance of material pairs with respect to friction, wear and surface roughness …


Design And Performance Evaluation Of A New Spatial Reuse Firewire Protocol, Vijay Chandramohan Sep 2003

Design And Performance Evaluation Of A New Spatial Reuse Firewire Protocol, Vijay Chandramohan

USF Tampa Graduate Theses and Dissertations

New generations of video surveillance systems are expected to possess a large-scale network of intelligent video cameras with built-in image processing capabilities. These systems need to be tethered for reasons of bandwidth and power requirements. To support economical installation of video cameras and to manage the huge volume of information flow in these networks, there is a need for new shared-medium daisy-chained physical and medium access control (bus arbitration) layer communication protocols.

This thesis describes the design principles of Spatial reuse FireWire Protocol (SFP), a novel request/grant bus arbitration protocol, architected for an acyclic daisy-chained network topology. SFP is a …


Graph-Theoretic Techniques For Web Content Mining, Adam Schenker Sep 2003

Graph-Theoretic Techniques For Web Content Mining, Adam Schenker

USF Tampa Graduate Theses and Dissertations

In this dissertation we introduce several novel techniques for performing data mining on web documents which utilize graph representations of document content. Graphs are more robust than typical vector representations as they can model structural information that is usually lost when converting the original web document content to a vector representation. For example, we can capture information such as the location, order and proximity of term occurrence, which is discarded under the standard document vector representation models. Many machine learning methods rely on distance computations, centroid calculations, and other numerical techniques. Thus many of these methods have not been applied …


Characterization And Modeling Of Planar Spiral Inductors And Pad Stack Parasitic Effects, John Capwell Sep 2003

Characterization And Modeling Of Planar Spiral Inductors And Pad Stack Parasitic Effects, John Capwell

USF Tampa Graduate Theses and Dissertations

This thesis concentrates on RF/microwave characterization and modeling of planar spiral inductors and pad stack parasitics. The inductors varied in size from 1.9 to 15.3 nH. Several approaches were examined for modeling the planar spiral inductors. The approach developed herein is built around an existing composite model (available in commercial computer-aided design software), with added series and shunt impedances at both the input and output of the existing composite model. Artificial neural network (ANN) software was used to determine the correction impedance values. Another approach investigated was to model the S-parameters of the inductor using a space- mapping model of …


P-X Measurements For 2-Ethoxyethanol And Four Chlorinated Hydrocarbons At 303.15 K, Salil Milan Pathare Sep 2003

P-X Measurements For 2-Ethoxyethanol And Four Chlorinated Hydrocarbons At 303.15 K, Salil Milan Pathare

USF Tampa Graduate Theses and Dissertations

Total pressure measurements at 303.15 K are reported for the binary systems of 2-ethoxyethanol with carbon tetrachloride, chloroform, 1,2-dichloroethane and dichloromethane. Total pressure measurements for the system of hexane and 2-ethoxyethanol were also made to check the validity of the experimental apparatus and procedure. These measurements were taken according to the static method proposed by Van Ness (1975). Data reduction was accomplished using Barker's Method. The modified Margules equation was used as a model for the excess Gibbs free energy (GE) and parameter values were obtained by regression of the experimental data.

The obtained data were used to …


Exchanges For Complex Commodities: Toward A General-Purpose System For On-Line Trading, John Hershberger Aug 2003

Exchanges For Complex Commodities: Toward A General-Purpose System For On-Line Trading, John Hershberger

USF Tampa Graduate Theses and Dissertations

The modern economy includes a variety of markets, and the Internet has opened opportunities for efficient on-line trading. Researchers have developed algorithms for various auctions, which have become a popular means for on-line sales. They have also designed algorithms for exchange-based markets, similar to the traditional stock exchange, which support fast-paced trading of rigidly standardized securities. In contrast, there has been little work on exchanges for complex nonstandard commodities, such as used cars or collectible stamps.

We propose a formal model for trading of complex goods, and present an automated exchange for a limited version of this model. The exchange …


A Reinforcement Learning Approach To Obtain Treatment Strategies In Sequential Medical Decision Problems, Radhika Poolla Aug 2003

A Reinforcement Learning Approach To Obtain Treatment Strategies In Sequential Medical Decision Problems, Radhika Poolla

USF Tampa Graduate Theses and Dissertations

Medical decision problems are extremely complex owing to their dynamic nature, large number of variable factors, and the associated uncertainty. Decision support technology entered the medical field long after other areas such as the airline industry and the manufacturing industry. Yet, it is rapidly becoming an indispensable tool in medical decision making problems including the class of sequential decision problems. In these problems, physicians decide on a treatment plan that optimizes a benefit measure such as the treatment cost, and the quality of life of the patient. The last decade saw the emergence of many decision support applications in medicine. …


Packet Loss Concealment In Voice Over Internet, Rishikesh S. Gokhale Jul 2003

Packet Loss Concealment In Voice Over Internet, Rishikesh S. Gokhale

USF Tampa Graduate Theses and Dissertations

Traditional telephony networks with their cumbersome and costly infrastructures are being replaced with voice being transmitted over the Internet. The Internet is a very commonly used technology that was traditionally used to transmit data. With the availability of large bandwidth and high data rates the transmission of data, voice and video over the Internet is gaining popularity. Voice is a real time application and the biggest problem it faces is the loss of packets due to network congestion. The Internet implements protocols to detect and retransmit the lost packets. However, for a real time application it is too late before …