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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat Jan 2004

Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat

Electronic Theses and Dissertations

Light scattering-based techniques are being developed for non-invasive diagnostics of inhomogeneous media in various fields, such as medicine, biology, and material characterization. However, as most media of interest are highly scattering and have a complex structure, it is difficult to obtain a full analytical solution of the scattering problem without introducing approximations and assumptions about the properties of the system under consideration. Moreover, most of the previous studies deal with idealized scattering situations, rarely encountered in practice. This dissertation provides new analytical, numerical, and experimental solutions to describe subtle effects introduced by the properties of the light sources, and by …

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Water Quality Variations During Nitrification In Drinking Water Distribution Systems, David W. Webb Jan 2004

Water Quality Variations During Nitrification In Drinking Water Distribution Systems, David W. Webb

Electronic Theses and Dissertations

This thesis documents the relationship among the major water quality parameters during a nitrification episode. Nitrification unexpectedly occurred in a chloraminated pilot drinking water distribution system practicing with a 4.0 mg/L as Cl2 residual dosed at 4.5:1 Cl2:NH3-N. Surface, ground and sea water were treated and disinfected with monochloramines to produce finished water quality similar to regional utility water quality. PVC, galvanized, unlined cast iron and lined iron pipes were harvested from regional distribution systems and used to build eighteen pilot distribution systems (PDSs). The PDSs were operated at a 5-day hydraulic residence time (HRT) and ambient temperatures. As seasonal …

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Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu Jan 2004

Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu

Electronic Theses and Dissertations

The content of this dissertation consists of three parts. In the first part, optimal control strategies are developed for Unified Power Flow Controller (UPFC) following the clearance of fault conditions. UPFC is one of the most versatile Flexible AC Transmission devices (FACTs) that have been implemented thus far. The optimal control scheme is composed of two parts. The first is an optimal stabilization control, which is an open-loop ‘Bang’ type of control. The second is an suboptimal damping control, which consists of segments of ‘Bang’ type control with switching functions the same as those of a corresponding approximate linear system. …

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Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf Jan 2004

Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf

Electronic Theses and Dissertations

This paper presents the results of a study on exhaust manifold design for a NASCAR Restrictor plate internal combustion engine. A computer simulation model was developed using Ricardo WAVE software. WAVE is a computer-aided engineering code developed by Ricardo to analyze the dynamics of pressure waves, mass flows and energy losses in ducts, plenums and the intake and exhaust manifolds of various systems and machines. [1] The model was validated against experimental data from a current NASCAR Winston Cup restrictor plate motor. The parameters studied have been exhaust manifold diameters and lengths. A response surface analysis of the simulation output …

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Surface Chemistry Of Application Specific Pads And Copper Chemical Mechanical Planarization, Sameer Arun Deshpande Jan 2004

Surface Chemistry Of Application Specific Pads And Copper Chemical Mechanical Planarization, Sameer Arun Deshpande

Electronic Theses and Dissertations

Advances in the interconnection technology have played a key role in the continued improvement of the integrated circuit (IC) density, performance and cost. Copper (Cu) metallization, dual damascenes processing and integration of copper with low dielectric constant material are key issues in the IC industries. Chemical mechanical planarization of copper (CuCMP) has emerged as an important process for the manufacturing of ICs. Usually, Cu-CMP process consists of several steps such as the removal of surface layer by mechanical action of the pad and the abrasive particles, the dissolution of the abraded particles in the CMP solution, and the protection of …

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Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz Jan 2004

Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz

Electronic Theses and Dissertations

Due to increasing demand on deployable surveillance systems in recent years, object tracking and activity recognition are receiving considerable attention in the research community. This thesis contributes to both the tracking and the activity recognition components of a surveillance system. In particular, for the tracking component, we propose two different approaches for tracking objects in video acquired by mobile cameras, each of which uses a different object shape representation. The first approach tracks the centroids of the objects in Forward Looking Infrared Imagery (FLIR) and is suitable for tracking objects that appear small in airborne video. The second approach tracks …

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Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali Jan 2004

Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali

Electronic Theses and Dissertations

Modern radar and communication systems have experienced a tremendous increase in the number of antennas onboard, on the ground, and in orbital space. This places a burden due to the confined volume and limited weight requirements especially in space applications. The reconfigurable antenna is a promising and exciting new type of antenna, where through the use of appropriate switches the antenna can be structurally reconfigured, to maintain the elements near their resonant dimensions for several frequency bands. This increases the bandwidth of the antenna dramatically, which enables the use of one antenna for several applications. Four novel reconfigurable antenna elements …

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Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua Jan 2004

Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua

Electronic Theses and Dissertations

In this thesis, the parallel barrier analysis feature in the Federal Highway Administration Traffic Noise Model (FHWA TNM), which is based on RAYVERB was used to explore the effects of multiple reflections due to single and parallel barriers and the use of absorptive treatment. Database was developed from the data collected from previous research efforts was used to generate a best fit equation model that can be used as a predetermining tool to determine the magnitude of parallel barrier insertion loss. The best fit equation model was then used to test against measured/model result and TNM prediction results for its …

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Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund Jan 2004

Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund

Electronic Theses and Dissertations

To create a realistic environment, many simulations require simulated agents with human behavior patterns. Manually creating such agents with realistic behavior is often a tedious and time-consuming task. This dissertation describes a new approach that automatically builds human behavior models for simulated agents by observing human performance. The research described in this dissertation synergistically combines Context-Based Reasoning, a paradigm especially developed to model tactical human performance within simulated agents, with Genetic Programming, a machine learning algorithm to construct the behavior knowledge in accordance to the paradigm. This synergistic combination of well-documented AI methodologies has resulted in a new algorithm that …

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Inelastic Dynamic Behavior And Design Of Hybrid Coupled Wall Systems, Mohamed Hassan Jan 2004

Inelastic Dynamic Behavior And Design Of Hybrid Coupled Wall Systems, Mohamed Hassan

Electronic Theses and Dissertations

A key consideration in seismic design of buildings is to ensure that the lateral load resisting system has an appropriate combination of strength, stiffness and energy dissipation capacity. Hybrid coupled wall systems, in which steel beams are used to couple two or more reinforced concrete shear walls in series, can be designed to have these attributes and therefore have the potential to deliver good performance under severe seismic loading. This research presents an investigation of the seismic behavior of this type of structural system. System response of 12- and 18-story high prototypes is studied using transient finite element analyses that …

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Location Of Sinkhole Confining Breach Using Groundwater Flow Patterns Derived From Cone Penetration Testing, Natalie Romina Marinuzzi Jan 2004

Location Of Sinkhole Confining Breach Using Groundwater Flow Patterns Derived From Cone Penetration Testing, Natalie Romina Marinuzzi

Electronic Theses and Dissertations

Dynamic forces in the hydrologic cycle move underground water through Florida's carbonate rocks dissolving chemical components of the rocks, leaving behind caves, solution pipes, and other voids that result in a karst terrain. Ravelling is the common subsidence mechanism throughout most of Florida where unconsolidated materials filter downward into voids in the underlying limestone. A cavity in the overburden develops and enlarges over a period of many years. The enlarged cavity is also known as sinkhole. The investigations of sinkhole characteristics and potential involve studying the regional geology, hydrology and mapping historic sinkholes that have occurred in the area. Use …

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An Approach To Automating Data Collection For Simulation, Irin Portnaya Jan 2004

An Approach To Automating Data Collection For Simulation, Irin Portnaya

Electronic Theses and Dissertations

In past years many industries have utilized simulation as a means for decision making. That wave has introduced simulation as a powerful optimization and development tool in the manufacturing industry. Input data collection is a significant and complex event in the process of simulation. The simulation professionals have grown to accept it is as a strenuous but necessary task. Due to the nature of this task, data collection problems are numerous and vary depending on the situation. These problems may involve time consumption, lack of data, lack of structure, etc. This study concentrates on the challenges of input data collection …

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Finite Element Analysis Of A Test Specimen For Strength Of A Co-Polymer Layer At A Bone-Implant Interface, Nitin Chhabra Jan 2004

Finite Element Analysis Of A Test Specimen For Strength Of A Co-Polymer Layer At A Bone-Implant Interface, Nitin Chhabra

Electronic Theses and Dissertations

The aim of this work is to evaluate the mechanical strength of a co-polymer of 2-hydroxyethylmethacrylate (HEMA) and methylmethacrylate (MMA), so that it can be applied as an interfacial layer between bone cement and steel implants to improve their performance and life. Finite element (FE) analysis techniques are used to assess the behavior of the interface layer under static and dynamic loading conditions. The material property of the co-polymer is a function of its composition and water saturation. The factors affecting the strength of the bone-implant interface are many. Implant interfacial fracture can lead to decreased stability. Fatigue life is …

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Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki Jan 2004

Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki

Electronic Theses and Dissertations

Video-On-Demand (VOD) has appeared as an important technology for many multimedia applications such as news on demand, digital libraries, home entertainment, and distance learning. In its simplest form, delivery of a video stream requires a dedicated channel for each video session. This scheme is very expensive and non-scalable. To preserve server bandwidth, many users can share a channel using multicast. Two types of multicast have been considered. In a non-periodic multicast setting, users make video requests to the server; and it serves them according to some scheduling policy. In a periodic broadcast environment, the server does not wait for service …

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Analysis And Modeling Of The Eds Maglev System Based On The Halbach Permanent Magnet Array, Qinghua Han Jan 2004

Analysis And Modeling Of The Eds Maglev System Based On The Halbach Permanent Magnet Array, Qinghua Han

Electronic Theses and Dissertations

Electro-dynamic suspension (EDS) Magnetic levitation (Maglev) with its advantage in maintenance, safety, efficiency, speed, and noise is regarded as a leading candidate for the next generation transportation / space launch assist system. The Halbach array due to its unique magnetic field feature has been widely used in various applications. The EDS system using Halbach arrays leads to the potential EDS system without super-conductor (SC) technology. In this thesis, the Halbach array magnetic field and the dynamics of a novel Halbach array EDS Maglev system were considered. The practical Halbach array magnetic field was analyzed using both a Fourier series approach …

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Basic Study Of Micromachined Dep (Dielectrophoretic) Manipulator, Vivek Sundaram Jan 2004

Basic Study Of Micromachined Dep (Dielectrophoretic) Manipulator, Vivek Sundaram

Electronic Theses and Dissertations

The capability of manipulating microparticle in small volumes is fundamental to many biological and medical applications, including separation and detection of cells. The development of microtools for effective sample handling and separation in such volumes is still a challenge. DEP (dielectrophoresis) is one of the most widely used methods in handling the microparticles. In this thesis we show that forces generated by nonuniform electric field (DEP) can be used for trapping and separating the microparticles (latex beads). This work further explores the DEP force based on different electrode geometries and medium conductivity. A micromanipulator for latex bead separation was designed, …

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Improving Project Management With Simulation And Completion Distributi, Grant Cates Jan 2004

Improving Project Management With Simulation And Completion Distributi, Grant Cates

Electronic Theses and Dissertations

Despite the critical importance of project completion timeliness, management practices in place today remain inadequate for addressing the persistent problem of project completion tardiness. Uncertainty has been identified as a contributing factor in late projects. This uncertainty resides in activity duration estimates, unplanned upsetting events, and the potential unavailability of critical resources. This research developed a comprehensive simulation based methodology for conducting quantitative project completion-time risk assessments. The methodology enables project stakeholders to visualize uncertainty or risk, i.e. the likelihood of their project completing late and the magnitude of the lateness, by providing them with a completion time distribution function …

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Detection And Evaluation Of Exisiting Pavement System With Brick Base, Karishma Desai Jan 2004

Detection And Evaluation Of Exisiting Pavement System With Brick Base, Karishma Desai

Electronic Theses and Dissertations

At the turn of the century, the City of Orlando initiated the "Neighborhood Horizon Program." This program involved local citizens to help improve their community resources by engaging in a process of planning where the problems associated with the communities were identified. Many residents favored to bring back the brick roads that were overlaid with asphalt concrete to provided better transportation in the mid 1900s. With majority of the neighborhood streets already bricked, removing asphalt ensured safety, served as a technique for slowing traffic, and added to the historical integrity. Since there were no official documentations available that stated the …

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Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong Jan 2004

Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong

Electronic Theses and Dissertations

As digital images become ubiquitous in many applications, the need for efficient and effective retrieval techniques is more demanding than ever. Query by Example (QBE) and Query by Concept (QBC) are among the most popular query models. The former model accepts example images as queries and searches for similar ones based on low-level features such as colors and textures. The latter model allows queries to be expressed in the form of high-level semantics or concept words, such as "boat" or "car," and finds images that match the specified concepts. Recent research has focused on the connections between these two models …

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Degradation Of Halogenated Aliphatic Compounds In Sequential Anaerobic, Scott Hoxworth Jan 2004

Degradation Of Halogenated Aliphatic Compounds In Sequential Anaerobic, Scott Hoxworth

Electronic Theses and Dissertations

The objective of this study was to utilize an alternating anaerobic/aerobic sequence to biologically transform perchloroethylene to non-hazardous end products such as ethylene, CO2 and H2 using a single microbial consortia in a methanogenic and/or a homoacetogenic environment followed by a aerobic methanotrophic environment. Reductive dechlorination of PCE and TCE to cDCE and VC in an anaerobic environment is typically carried out by methanogens, sulfidogens, or homoacetogens but often (e.g. in-situ) leads to an accumulation of daughter compounds (cDCE, VC) which are more toxic than their parent compounds (PCE, TCE). Furthermore, PCE is resistant to degradation in aerobic environments while …

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Two Dimensional Linear Finite Element Analysis Of Post-Tensioned Beams, Rodolfo Hutchinson Jan 2004

Two Dimensional Linear Finite Element Analysis Of Post-Tensioned Beams, Rodolfo Hutchinson

Electronic Theses and Dissertations

The objective of this research project was to create a Finite Element Routine for the Linear Analysis of Post-Tensioned beams using the program CALFEM® [20] developed at the division of Structural Mechanics in Lund University, Sweden. The program CALFEM and our own made files were written in MATLAB, an easy to learn and user-friendly computer language. The approach used in this thesis for analyzing the composite beam consists in embedding the steel tendons at the exact location where they intersect the concrete parent elements, without moving the concrete parent element nodes. The steel tendons are represented as one dimensional bar …

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Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung Jan 2004

Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung

Electronic Theses and Dissertations

In this thesis, we aim at modeling some aspects of the functional role of emotions on an autonomous embodied agent. We begin by describing our robotic prototype, Cherry--a robot with the task of being a tour guide and an office assistant for the Computer Science Department at the University of Central Florida. Cherry did not have a formal emotion representation of internal states, but did have the ability to express emotions through her multimodal interface. The thesis presents the results of a survey we performed via our social informatics approach where we found that: (1) the idea of having emotions …

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Fpga-Based Design Of A Maximum-Power-Point Tracking System For Space A, Todd Persen Jan 2004

Fpga-Based Design Of A Maximum-Power-Point Tracking System For Space A, Todd Persen

Electronic Theses and Dissertations

Satellites need a source of power throughout their missions to help them remain operational for several years. The power supplies of these satellites, provided primarily by solar arrays, must have high efficiencies and low weights in order to meet stringent design constraints. Power conversion from these arrays is required to provide robust and reliable conversion which performs optimally in varying conditions of peak power, solar flux, and occlusion conditions. Since the role of these arrays is to deliver power, one of the principle factors in achieving maximum power output from an array is tracking and holding its maximum-power point. This …

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Dewatering Of Biosolids By Sodium Ferrate, Andrea Rios Jan 2004

Dewatering Of Biosolids By Sodium Ferrate, Andrea Rios

Electronic Theses and Dissertations

This study was conducted to evaluate the effectiveness of the liquid form of ferrate for dewatering of biosolids from wastewater treatment facilities. Two different ferrate products prepared using calcium hypochlorite and sodium hypochlorite were used. Samples of anaerobic digested sludge and waste activated sludge with solids content of 2.1% and 0.95 %, respectively were conditioned with both products to evaluate and compare their effectiveness. Centrifugation and filtration of the sludge after conditioning were used. For centrifugation the volume reduction and the turbidity of the supernatant after centrifugation were evaluated. For filtration, the Capillary Suction Time test was used. The optimum …

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Low Power Cmos Circuit Design And Reliability Analysis For Wireless Me, Md Anwar Sadat Jan 2004

Low Power Cmos Circuit Design And Reliability Analysis For Wireless Me, Md Anwar Sadat

Electronic Theses and Dissertations

A sensor node 'AccuMicroMotion' is proposed that has the ability to detect motion in 6 degrees of freedom for the application of physiological activity monitoring. It is expected to be light weight, low power, small and cheap. The sensor node may collect and transmit 3 axes of acceleration and 3 axes of angular rotation signals from MEMS transducers wirelessly to a nearby base station while attached to or implanted in human body. This dissertation proposes a wireless electronic system-on-a-single-chip to implement the sensor in a traditional CMOS process. The system is low power and may operate 50 hours from a …

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Supporting Real-Time Pda Interaction With Virtual Environment, Radhey Shah Jan 2004

Supporting Real-Time Pda Interaction With Virtual Environment, Radhey Shah

Electronic Theses and Dissertations

Personal Digital Assistants (PDAs) are becoming more and more powerful with advances in technology and are expanding their applications in a variety of fields. This work explores the use of PDAs in Virtual Environments (VE). The goal is to support highly interactive bi-directional user interactions in Virtual Environments in more natural and less cumbersome ways. A proxy-based approach is adopted to support a wide-range of handheld devices and have a multi-PDA interaction with the virtual world. The architecture consists of three components in the complete system, a PDA, a desktop that acts as a proxy and Virtual Environment Software Sandbox …

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Commissioning Of An Arc-Melting/Vacuum Quench Furnace Facility For Fabrication Of Ni-Ti-Fe Shape Memory Alloys, And The Characterization, Jagat Singh Jan 2004

Commissioning Of An Arc-Melting/Vacuum Quench Furnace Facility For Fabrication Of Ni-Ti-Fe Shape Memory Alloys, And The Characterization, Jagat Singh

Electronic Theses and Dissertations

Shape memory alloys when deformed can produce strains as high as 8%. Heating results in a phase transformation and associated recovery of all the accumulated strain, a phenomenon known as shape memory. This strain recovery can occur against large forces, resulting in their use as actuators. The goal of this project is to lower the operating temperature range of shape memory alloys in order for them to be used in cryogenic switches, seals, valves, fluid-line repair and self-healing gaskets for space related technologies. The Ni-Ti-Fe alloy system, previously used in Grumman F-14 aircrafts and activated at 120 K, is further …

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An Approach For Computing Intervisibility Using Graphical Processing U, Judd Tracy Jan 2004

An Approach For Computing Intervisibility Using Graphical Processing U, Judd Tracy

Electronic Theses and Dissertations

In large scale entity-level military force-on-force simulations it is essential to know when one entity can visibly see another entity. This visibility determination plays an important role in the simulation and can affect the outcome of the simulation. When virtual Computer Generated Forces (CGF) are introduced into the simulation these intervisibilities must now be calculated by the virtual entities on the battlefield. But as the simulation size increases so does the complexity of calculating visibility between entities. This thesis presents an algorithm for performing these visibility calculations using Graphical Processing Units (GPU) instead of the Central Processing Units (CPU) that …

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Image Based View Synthesis, Jiangjian Xiao Jan 2004

Image Based View Synthesis, Jiangjian Xiao

Electronic Theses and Dissertations

This dissertation deals with the image-based approach to synthesize a virtual scene using sparse images or a video sequence without the use of 3D models. In our scenario, a real dynamic or static scene is captured by a set of un-calibrated images from different viewpoints. After automatically recovering the geometric transformations between these images, a series of photo-realistic virtual views can be rendered and a virtual environment covered by these several static cameras can be synthesized. This image-based approach has applications in object recognition, object transfer, video synthesis and video compression. In this dissertation, I have contributed to several sub-problems …

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Hybrid And Hierarchical Image Registration Techniques, Dongjiang Xu Jan 2004

Hybrid And Hierarchical Image Registration Techniques, Dongjiang Xu

Electronic Theses and Dissertations

A large number of image registration techniques have been developed for various types of sensors and applications, with the aim to improve the accuracy, computational complexity, generality, and robustness. They can be broadly classified into two categories: intensity-based and feature-based methods. The primary drawback of the intensity-based approaches is that it may fail unless the two images are misaligned by a moderate difference in scale, rotation, and translation. In addition, intensity-based methods lack the robustness in the presence of non-spatial distortions due to different imaging conditions between images. In this dissertation, the image registration is formulated as a two-stage hybrid …

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