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Meta-Raps: Parameter Setting And New Applications, Seyhun Hepdogan Jan 2006

Meta-Raps: Parameter Setting And New Applications, Seyhun Hepdogan

Electronic Theses and Dissertations

Recently meta-heuristics have become a popular solution methodology, in terms of both research and application, for solving combinatorial optimization problems. Meta-heuristic methods guide simple heuristics or priority rules designed to solve a particular problem. Meta-heuristics enhance these simple heuristics by using a higher level strategy. The advantage of using meta-heuristics over conventional optimization methods is meta-heuristics are able to find good (near optimal) solutions within a reasonable computation time. Investigating this line of research is justified because in most practical cases with medium to large scale problems, the use of meta-heuristics is necessary to be able to find a solution ...


User-Centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications, Cali Fidopiastis Jan 2006

User-Centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications, Cali Fidopiastis

Electronic Theses and Dissertations

Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality ...


Synchronization In Advanced Optical Communications, Inwoong Kim Jan 2006

Synchronization In Advanced Optical Communications, Inwoong Kim

Electronic Theses and Dissertations

The objective of this dissertation is to generate high power ultrashort optical pulses from an all-semiconductor mode-locked laser system. The limitations of semiconductor optical amplifier in high energy, ultrashort pulse amplification are reviewed. A method to overcome the fundamental limit of small stored energy inside semiconductor optical amplifier called "eXtreme Chirped Pulse Amplification (X-CPA)" is proposed and studied theoretically and experimentally. The key benefits of the concept of X-CPA are addressed. Based on theoretical and experimental study, an all-semiconductor mode-locked X-CPA system consisting of a mode-locked master oscillator, an optical pulse pre-stretcher, a semiconductor optical amplifier (SOA) pulse picker, an ...


Development Of Thermally Processed Nanocomposites With Controlled Surfaces, Petya Georgieva Jan 2006

Development Of Thermally Processed Nanocomposites With Controlled Surfaces, Petya Georgieva

Electronic Theses and Dissertations

The ever increasing need for technology development requires the integration of inexpensive, light weight and high strength materials which are able to meet the high standards and specifications for various engineering applications. The intention of this work is to show that the suitable material selection and the utilization of plasma spray processing can be of potential interest to a large number of industrial, biomedical and everyday life applications. This research demonstrates also that plasma processing is a promising engineering tool for multifunctional coatings and near-net-shape manufacturing. Further, the theoretical and experimental results are combined in order to explain the mechanisms ...


Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (Esd) Protection Structures, Javier Salcedo Jan 2006

Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (Esd) Protection Structures, Javier Salcedo

Electronic Theses and Dissertations

The technology evolution and complexity of new circuit applications involve emerging reliability problems and even more sensitivity of integrated circuits (ICs) to electrostatic discharge (ESD)-induced damage. Regardless of the aggressive evolution in downscaling and subsequent improvement in applications' performance, ICs still should comply with minimum standards of ESD robustness in order to be commercially viable. Although the topic of ESD has received attention industry-wide, the design of robust protection structures and circuits remains challenging because ESD failure mechanisms continue to become more acute and design windows less flexible. The sensitivity of smaller devices, along with a limited understanding of ...


Heuristic 3d Reconstruction Of Irregular Spaced Lidar, Nicholas Shorter Jan 2006

Heuristic 3d Reconstruction Of Irregular Spaced Lidar, Nicholas Shorter

Electronic Theses and Dissertations

As more data sources have become abundantly available, an increased interest in 3D reconstruction has emerged in the image processing academic community. Applications for 3D reconstruction of urban and residential buildings consist of urban planning, network planning for mobile communication, tourism information systems, spatial analysis of air pollution and noise nuisance, microclimate investigations, and Geographical Information Systems (GISs). Previous, classical, 3D reconstruction algorithms solely utilized aerial photography. With the advent of LIDAR systems, current algorithms explore using captured LIDAR data as an additional feasible source of information for 3D reconstruction. Preprocessing techniques are proposed for the development of an autonomous ...


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

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

Electronic Theses and Dissertations

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


Integrated Inp Photonic Switches, Daniel May-Arrioja Jan 2006

Integrated Inp Photonic Switches, Daniel May-Arrioja

Electronic Theses and Dissertations

Photonic switches are becoming key components in advanced optical networks because of the large variety of applications that they can perform. One of the key advantages of photonic switches is that they redirect or convert light without having to make any optical to electronic conversions and vice versa, thus allowing networking functions to be lowered into the optical layer. InP-based switches are particularly attractive because of their small size, low electrical power consumption, and compatibility with integration of laser sources, photo-detectors, and electronic components. In this dissertation the development of integrated InP photonic switches using an area-selective zinc diffusion process ...


Rapid Prototyping Of Microfluidic Packages, Michael Pepper Jan 2006

Rapid Prototyping Of Microfluidic Packages, Michael Pepper

Electronic Theses and Dissertations

In the area of MEMS there exists a tremendous need for communication between the micro-device and the macro world. A standard protocol or at least multiple standards would be of great use. Electrical connections have been standardized for many uses and configurations by the integrated circuit industry. Standardization in the IC industry has created a marketplace for digital devices unprecedented. In addition to the number of "off the shelf" products available, there exists the possibility for consumers to mix and match many devices from many different manufacturers. This research proposes some similar solutions as those for integrated circuits for fluid ...


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

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

Electronic Theses and Dissertations

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


Sarp Net: A Secure, Anonymous, Reputation-Based, Peer-To-Peer Network, Sean Mondesire Jan 2006

Sarp Net: A Secure, Anonymous, Reputation-Based, Peer-To-Peer Network, Sean Mondesire

Electronic Theses and Dissertations

Since the advent of Napster, the idea of peer-to-peer (P2P) architectures being applied to file-sharing applications has become popular, spawning other P2P networks like Gnutella, Morpheus, Kazaa, and BitTorrent. This growth in P2P development has nearly eradicated the idea of the traditional client-server structure in the file-sharing model, now placing emphasizes on faster query processing, deeper levels of decentralism, and methods to protect against copyright law violation. SARP Net is a secure, anonymous, decentralized, P2P overlay network that is designed to protect the activity of its users in its own file-sharing community. It is secure in the fact that public-key ...


Design And Performance Evaluation Of An Integrated Miniature Single Stage Centrifugal Compressor And Permanent Magnet Synchronous Motor, Dipjyoti Acharya Jan 2006

Design And Performance Evaluation Of An Integrated Miniature Single Stage Centrifugal Compressor And Permanent Magnet Synchronous Motor, Dipjyoti Acharya

Electronic Theses and Dissertations

An attempt has been made in this present work to design, fabricate and performance evaluate an integrated single stage centrifugal compressor and permanent magnet synchronous motor which is a key component of the reverse brayton cycle cryocooler. An off the shelf compressor – the driven and electric motor – the driver was not available commercially to suffice the requirements of the reverse brayton cryocooler. The integrated compressor-motor system was designed and tested with air as the working fluid at mass flow rate of 7.3 grams per sec, with a compression ratio of 1.58 and driven by a 2 KW permanent ...


Commissioning Of A Dynamic Mechanical Analyzerfor The Characterization Of Low Temperature Nitife Shape Memory Alloys, Maruthi Diwakar Nandiraju Jan 2006

Commissioning Of A Dynamic Mechanical Analyzerfor The Characterization Of Low Temperature Nitife Shape Memory Alloys, Maruthi Diwakar Nandiraju

Electronic Theses and Dissertations

NiTiFe shape memory alloys can undergo transformations between cubic, trigonal and monoclinic phases at low temperatures. The low hysteresis associated with the trigonal R-phase transformation make them candidates for actuator applications at low temperatures. However, the literature available on these alloys is limited and there is a need to establish processing structure-property correlations. This study was undertaken with the objective of determining and understanding such correlations in a Ni46.8Ti50Fe3.2 alloy. First, a dynamic mechanical analyzer (DMA) was successfully commissioned to facilitate mechanical testing between -150 and 600ºC. The experiments performed over selected ranges of stress and temperature probed ...


Alumina-Aluminum Titanate-Titania Nanocomposite: Synthesis, Sintering Studies, Assessment Of Bioactivity And Its Mechanical And Electrical Properties, Vikas Somani Jan 2006

Alumina-Aluminum Titanate-Titania Nanocomposite: Synthesis, Sintering Studies, Assessment Of Bioactivity And Its Mechanical And Electrical Properties, Vikas Somani

Electronic Theses and Dissertations

This thesis reports the development, synthesis and characterization of a ceramic-ceramic nanocomposite system for its possible application as structural and electronic biomaterial in the biomedical industry. The study selected and synthesized alumina-aluminum titanate-titania (Al2O3-Al2TiO5-TiO2) nanoceramic composite using a simple Sol-Gel technique, which can be easily reproduced. Aluminum propoxide and titanium propoxide were used as precursor chemicals. Propanol and 2- methoxy ethanol were used as solvent and stabilizer, respectively. Thermal analyses were performed for a systematic understanding of phase evolution from the synthesized gel. X-Ray diffraction technique was used to confirm the phase evolution, phase purity, crystallite size and crystal structure ...


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

Developing Microscopic Toll Plaza Model Using Paramics, Nezamuddin Nezamuddin

Electronic Theses and Dissertations

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


Object Association Across Multiple Moving Cameras In Planar Scenes, Yaser Sheikh Jan 2006

Object Association Across Multiple Moving Cameras In Planar Scenes, Yaser Sheikh

Electronic Theses and Dissertations

In this dissertation, we address the problem of object detection and object association across multiple cameras over large areas that are well modeled by planes. We present a unifying probabilistic framework that captures the underlying geometry of planar scenes, and present algorithms to estimate geometric relationships between different cameras, which are subsequently used for co-operative association of objects. We first present a local1 object detection scheme that has three fundamental innovations over existing approaches. First, the model of the intensities of image pixels as independent random variables is challenged and it is asserted that useful correlation exists in intensities of ...


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

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

Electronic Theses and Dissertations

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


Simulation Of Random Set Covering Problems With Known Optimal Solutions And Explicitly Induced Correlations Amoong Coefficients, Nabin Sapkota Jan 2006

Simulation Of Random Set Covering Problems With Known Optimal Solutions And Explicitly Induced Correlations Amoong Coefficients, Nabin Sapkota

Electronic Theses and Dissertations

The objective of this research is to devise a procedure to generate random Set Covering Problem (SCP) instances with known optimal solutions and correlated coefficients. The procedure presented in this work can generate a virtually unlimited number of SCP instances with known optimal solutions and realistic characteristics, thereby facilitating testing of the performance of SCP heuristics and algorithms. A four-phase procedure based on the Karush-Kuhn-Tucker (KKT) conditions is proposed to generate SCP instances with known optimal solutions and correlated coefficients. Given randomly generated values for the objective function coefficients and the sum of the binary constraint coefficients for each variable ...


Wide Viewing Angle Liquid Crystal Displays, Qi Hong Jan 2006

Wide Viewing Angle Liquid Crystal Displays, Qi Hong

Electronic Theses and Dissertations

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


On The Use Of Variable Coherence In Inverse Scattering Problems, Erwan Baleine Jan 2006

On The Use Of Variable Coherence In Inverse Scattering Problems, Erwan Baleine

Electronic Theses and Dissertations

Even though most of the properties of optical fields, such as wavelength, polarization, wavefront curvature or angular spectrum, have been commonly manipulated in a variety of remote sensing procedures, controlling the degree of coherence of light did not find wide applications until recently. Since the emergence of optical coherence tomography, a growing number of scattering techniques have relied on temporal coherence gating which provides efficient target selectivity in a way achieved only by bulky short pulse measurements. The spatial counterpart of temporal coherence, however, has barely been exploited in sensing applications. This dissertation examines, in different scattering regimes, a variety ...


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

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

Electronic Theses and Dissertations

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


High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen Jan 2006

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the ...


Cognitive Training Transfer Using A Personal Computer-Based Game:A Close Quarters Battle Case Study, Michael Woodman Jan 2006

Cognitive Training Transfer Using A Personal Computer-Based Game:A Close Quarters Battle Case Study, Michael Woodman

Electronic Theses and Dissertations

Developers of Commercial off the Shelf (COTS) gaming software are making remarkable strides in increasing the realism of their software. This realism has caught the attention of the training community, which has traditionally sought system and operational replication in training systems such as flight simulators. Since games are designed and marketed for entertainment and not designed for training of tasks, questions exist about the effectiveness of games as a training system in achieving the desired transfer of skills to the actual environment. Numerous studies over the past ten years have documented that PC-based simulation training environments can offer effective training ...


Prediction And Allocation Of Live To Virtual Communication Bridging Resources, Stephanie Lackey Jan 2006

Prediction And Allocation Of Live To Virtual Communication Bridging Resources, Stephanie Lackey

Electronic Theses and Dissertations

This document summarizes a research effort focused on improving live-to-virtual (L-V) communication systems. The purpose of this work is to address a significant challenge facing the tactical communications training community through the development of the Live-to-Virtual Relay Radio Prediction Algorithm and implementation of the algorithm into an Integrated Live-to-Virtual Communications Server prototype device. The motivation for the work and the challenges of integrating live and virtual communications are presented. Details surrounding the formulation of the prediction algorithm and a description of the prototype system, hardware, and software architectures are shared. Experimental results from discrete event simulation analysis and prototype functionality ...


Enhancing Situational Awareness Through Haptics Interaction In Virtual Environment Training Systmes, Kelly Hale Jan 2006

Enhancing Situational Awareness Through Haptics Interaction In Virtual Environment Training Systmes, Kelly Hale

Electronic Theses and Dissertations

Virtual environment (VE) technology offers a viable training option for developing knowledge, skills and attitudes (KSA) within domains that have limited live training opportunities due to personnel safety and cost (e.g., live fire exercises). However, to ensure these VE training systems provide effective training and transfer, designers of such systems must ensure that training goals and objectives are clearly defined and VEs are designed to support development of KSAs required. Perhaps the greatest benefit of VE training is its ability to provide a multimodal training experience, where trainees can see, hear and feel their surrounding environment, thus engaging them ...


Analysis Of Complexity And Coupling Metrics Of Subsystems In Large Scale Software Systems, Harish Ramakrishnan Jan 2006

Analysis Of Complexity And Coupling Metrics Of Subsystems In Large Scale Software Systems, Harish Ramakrishnan

Electronic Theses and Dissertations

Dealing with the complexity of large-scale systems can be a challenge for even the most experienced software architects and developers. Large-scale software systems can contain millions of elements, which interact to achieve the system functionality. Managing and representing the complexity involved in the interaction of these elements is a difficult task. We propose an approach for analyzing the reusability, maintainability and complexity of such a complex large-scale software system. Reducing the dependencies between the subsystems increase the reusability and decrease the efforts needed to maintain the system thus reducing the complexity of the system. Coupling is an attribute that summarizes ...


Analyis Of Airborne Microwave Polarimetric Radiometer Measurements In The Presence Of Dynamic Platform Attitude Errors, Jean Yves Kabore Jan 2006

Analyis Of Airborne Microwave Polarimetric Radiometer Measurements In The Presence Of Dynamic Platform Attitude Errors, Jean Yves Kabore

Electronic Theses and Dissertations

There are numerous applications for airborne imaging systems in remote sensing, and this thesis deals with a new microwave polarimetric radiometer technique for inferring ocean surface wind direction [3, 5, 7]. This technique is based upon the anisotropy of the polarized ocean blackbody emissions at microwave frequencies relative to the azimuth angle between the microwave radiometer antenna "look" direction and the direction of the wind. Because of the weak wind direction signature, it is important that all systematic brightness temperature (Tb) errors be eliminated, especially those that vary with the radiometer antenna scan position (look direction). This can be accomplished ...


Up-Conversion In Rare-Earth Doped Micro-Particles Applied To New Emissive 2d Dislays, Anne Milliez Jan 2006

Up-Conversion In Rare-Earth Doped Micro-Particles Applied To New Emissive 2d Dislays, Anne Milliez

Electronic Theses and Dissertations

Up-conversion (UC) in rare-earth co-doped fluorides to convert diode laser light in the near infrared to red, green and blue visible light is applied to make possible high performance emissive displays. The infrared-to-visible UC in the materials we study is a sequential form of non-linear two photon absorption in which a strong absorbing constituent absorbs two low energy photons and transfers this energy to another constituent which emits visible light. Some of the UC emitters' most appealing characteristics for displays are: a wide color gamut with very saturated colors, very high brightness operation without damage to the emitters, long lifetimes ...


Automated Adaptive Data Center Generation For Meshless Methods, Eric Mitteff Jan 2006

Automated Adaptive Data Center Generation For Meshless Methods, Eric Mitteff

Electronic Theses and Dissertations

Meshless methods have recently received much attention but are yet to reach their full potential as the required problem setup (i.e. collocation point distribution) is still significant and far from automated. The distribution of points still closely resembles the nodes of finite volume-type meshes and the free parameter, c, of the radial-basis expansion functions (RBF) still must be tailored specifically to a problem. The localized meshless collocation method investigated requires a local influence region, or topology, used as the expansion medium to produce the required field derivatives. Tests have shown a regular cartesian point distribution produces optimal results, however ...


Polymer-Derived Si-Al-C-N Ceramics:Oxidation, Hot-Corrosion, And Structural Evolution, Yiguang Wang Jan 2006

Polymer-Derived Si-Al-C-N Ceramics:Oxidation, Hot-Corrosion, And Structural Evolution, Yiguang Wang

Electronic Theses and Dissertations

Polymer-derived ceramics are a new class of materials synthesized by thermal decomposition of polymer precursors. Previous studies have shown that the materials exhibit excellent thermo-mechanical properties and can be stable at temperatures up to 2000oC. Furthermore, the novel polymer-to-ceramics process enables the manipulation of the ceramic structures at the atomic/nano level by designing the chemistry of polymer precursors and controlling the pyrolysis conditions, thereby, the properties of ceramics. In this dissertation, oxidation/hot-corrosion behavior and the structural evolution of Si-Al-C-N ceramics have been studied. The structural evolution and crystallization behavior of the SiCN and SiAlCN ceramics are investigated using ...