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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Optical Fluid-Based Photonic And Display Devices, Su Xu Jan 2012

Optical Fluid-Based Photonic And Display Devices, Su Xu

Electronic Theses and Dissertations

Conventional solid-state photonic devices exhibit an ultra-high optical performance and durability, but minimal adaptability. Recently, optical fluid-based photonic and display devices are emerging. By dynamically manipulating the optical interface formed by liquids, the optical output can be reconfigured or adaptively tuned in real time. Such devices exhibit some unique characteristics that are not achievable in conventional solid-state photonic devices. Therefore, they open a gateway for new applications, such as image and signal processing, optical communication, sensing, and lab-on-a-chip, etc. Different operation principles of optical fluidbased photonic devices have been proposed, for instance fluidic pressure, electrochemistry, thermal effect, environmentally adaptive hydrogel, …


Non-Reciprocal Wave Transmission In Integrated Waveguide Array Isolators, Tony Yatming Ho Jan 2012

Non-Reciprocal Wave Transmission In Integrated Waveguide Array Isolators, Tony Yatming Ho

Electronic Theses and Dissertations

Non-reciprocal wave transmission is a phenomenon witnessed in certain photonic devices when the wave propagation dynamics through the device along one direction differs greatly from the dynamics along the counter-propagating direction. Specifically, it refers to significant power transfer occurring in one direction, and greatly reduced power transfer in the opposite direction. The resulting effect is to isolate the directionality of wave propagation, allowing transmission to occur along one direction only. Given the popularity of photonic integrated circuits (PIC), in which all the optical components are fabricated on the same chip so that the entire optical system can be made more …


Infrared Tapered Slot Antennas Coupled To Tunnel Diodes, Louis A. Florence Jan 2012

Infrared Tapered Slot Antennas Coupled To Tunnel Diodes, Louis A. Florence

Electronic Theses and Dissertations

Tapered slot antennas (TSAs) have seen considerable application in the millimeter-wave portion of the spectrum. Desirable characteristics of TSAs include symmetric E- and H-plane antenna patterns, and broad non-resonant bandwidths. We investigate extension of TSA operation toward higher frequencies in the thermal infrared (IR), using a metal-oxide-metal diode as the detector. Several different infrared TSA design forms are fabricated using electronbeam lithography and specially developed thin-film processes. The angular antenna patterns of TSA-coupled diodes are measured at 10.6 micrometer wavelength in both E- and H-planes, and are compared to results of finite-element electromagnetic modeling using Ansoft HFSS. Parameter studies are …


High-Efficiency Blue Phase Liquid Crystal Displays, Yan Li Jan 2012

High-Efficiency Blue Phase Liquid Crystal Displays, Yan Li

Electronic Theses and Dissertations

Blue phase liquid crystals (BPLCs) have a delicate lattice structure existing between chiral nematic and isotropic phases, with a stable temperature range of about 2 K. But due to short coherent length, these self-assembled nano-structured BPLCs have a fast response time. In the past three decades, the application of BPLC has been rather limited because of its narrow temperature range. In 2002, Kikuchi et al. developed a polymer stabilization method to extend the blue-phase temperature range to more than 60 K. This opens a new gateway for display and photonic applications. In this dissertation, I investigate the material properties of …


Laser Filamentation Interaction With Materials For Spectroscopic Applications, Matthew Weidman Jan 2012

Laser Filamentation Interaction With Materials For Spectroscopic Applications, Matthew Weidman

Electronic Theses and Dissertations

Laser filamentation is a non-diffracting propagation regime consisting of an intense core that is surrounded by an energy reservoir. For laser ablation based spectroscopy techniques such as Laser Induced Breakdown Spectroscopy (LIBS), laser filamentation enables the remote delivery of high power density laser radiation at long distances. This work shows a quasiconstant filament-induced mass ablation along a 35 m propagation distance. The mass ablated is sufficient for the application of laser filamentation as a sampling tool for plasma based spectroscopy techniques. Within the scope of this study, single-shot ablation was compared with multi-shot ablation. The dependence of ablated mass on …


State (Hydrodynamics) Identification In The Lower St. Johns River Using The Ensemble Kalman Filter, Hitoshi Tamura Jan 2012

State (Hydrodynamics) Identification In The Lower St. Johns River Using The Ensemble Kalman Filter, Hitoshi Tamura

Electronic Theses and Dissertations

This thesis presents a method, Ensemble Kalman Filter (EnKF), applied to a highresolution, shallow water equations model (DG ADCIRC-2DDI) of the Lower St. Johns River with observation data at four gauging stations. EnKF, a sequential data assimilation method for non-linear problems, is developed for tidal flow simulation for estimation of state variables, i.e., water levels and depth-integrated currents for overland unstructured finite element meshes. The shallow water equations model is combined with observation data, which provides the basis of the EnKF applications. In this thesis, EnKF is incorporated into DG ADCIRC-2DDI code to estimate the state variables. Upon its development, …


Failure Analysis Of Impact-Damaged Metallic Poles Repaired With Fiber Reinforced Polymer Composites, Robert Arthur Slade Jan 2012

Failure Analysis Of Impact-Damaged Metallic Poles Repaired With Fiber Reinforced Polymer Composites, Robert Arthur Slade

Electronic Theses and Dissertations

Metallic utility poles, light poles, and mast arms are intermittently damaged by vehicle collision. In many cases the vehicular impact does not cause immediate failure of the structure, but induces localized damage that may result in failure under extreme service loadings or can promote degradation and corrosion within the damaged region. Replacement of these poles is costly and often involves prolonged lane closures, service interruption, and temporary loss of functionality. Therefore, an in situ repair of these structures is required. This thesis examines the failure modes of damaged metallic poles reinforced with externally-bonded fiber reinforced polymer (FRP) composites. Several FRP …


X-Ray Radiation Enabled Cancer Detection And Treatment With Nanoparticles, Mainul Hossain Jan 2012

X-Ray Radiation Enabled Cancer Detection And Treatment With Nanoparticles, Mainul Hossain

Electronic Theses and Dissertations

Despite significant improvements in medical sciences over the last decade, cancer still continues to be a major cause of death in humans throughout the world. Parallel to the efforts of understanding the intricacies of cancer biology, researchers are continuously striving to develop effective cancer detection and treatment strategies. Use of nanotechnology in the modern era opens up a wide range of possibilities for diagnostics, therapies and preventive measures for cancer management. Although, existing strategies of cancer detection and treatment, using nanoparticles, have been proven successful in case of cancer imaging and targeted drug deliveries, they are often limited by poor …


The Development And Fabrication Of A Modular Vertical Reciprocating Conveyor System For The Transportation Of Materials To And From A Mezzanine., Matthew Paul Crum Dec 2011

The Development And Fabrication Of A Modular Vertical Reciprocating Conveyor System For The Transportation Of Materials To And From A Mezzanine., Matthew Paul Crum

Electronic Theses and Dissertations

The purpose of this developmental project was to design and fabricate a vertical reciprocating conveyor in order to eliminate the process of manually carrying 27 pound containers of plastic resin up and down a flight of offset space saver stairs. This project took place and was built for Phoenix Closures Incorporated. The conveyor was designed and built in house because there are no commercially available vertical reciprocating conveyors available that meet the necessary requirements.

The capabilities of the proposed vertical reciprocating conveyor are not limited to the carrying of the containers but designed to carry vacuum cleaners, tool boxes, and …


Innovative Design: Design Of A Press System And Molds To Produce A Skateboard Deck., George William Linke Dec 2011

Innovative Design: Design Of A Press System And Molds To Produce A Skateboard Deck., George William Linke

Electronic Theses and Dissertations

Skateboarding is a passion for many people. Homemade skateboard machinery has been fabricated throughout the country. While the demand for skateboards is steady; there is a steady growth in the homemade skateboard deck market. The desire to create a one of a kind deck that expresses a person's individualism is growing. This applied research and development effort - designing and fabricating a fluid powered press system and 2-part mold assembly for forming glue up laminations for skateboard decks - is an attempt to gain understanding of the different phases of the product design process.


New Test Set For Video Quality Benchmarking, Joaquin Raventos Dec 2011

New Test Set For Video Quality Benchmarking, Joaquin Raventos

Electronic Theses and Dissertations

A new test set design and benchmarking approach (US Patent pending) allows a "standard observer" to assess the end-to-end image quality characteristics of video imaging systems operating in day time or low-light conditions.

It uses randomized targets based on extensive application of Photometry, Geometrical Optics, and Digital Media.

The benchmarking takes into account the target’s contrast sensitivity, its color characteristics, and several aspects of human vision such as visual acuity and dynamic response. The standard observer is part of the "extended video imaging system" (EVIS).

The new test set allows image quality benchmarking by a panel of standard observers at …


Optimal Charging Scheduling For Battery Electric Vehicles Under Smart Grid., Nur Dayana Abd Rahman Dec 2011

Optimal Charging Scheduling For Battery Electric Vehicles Under Smart Grid., Nur Dayana Abd Rahman

Electronic Theses and Dissertations

A projected high penetration of battery electric vehicles (BEV s) in the market will introduce an additional load in the electricity grid. Furthermore, uncontrolled BEV charging from residential users will exacerbate the existing peak load during evening hours. In this thesis, we propose two optimization models to alleviate the impact of extra demand from electric vehicles on the power grid. The first is a centralized charging scheduling model that coordinates the charging among BEV users under the goal of minimizing the total electricity cost for all users. The second model uses a decentralized agent-based approach to scheduling the BEV charging. …


Comparative Evaluation Of Conventional Soldier Pile/Lagging Retention Systems Versus Soil Nailing Retention Systems., Abdul Amir Al-Helu 1966- Dec 2011

Comparative Evaluation Of Conventional Soldier Pile/Lagging Retention Systems Versus Soil Nailing Retention Systems., Abdul Amir Al-Helu 1966-

Electronic Theses and Dissertations

An investigation was made into the relative costs of excavation retention by two systems: conventional soldier pile-wale-tieback support, and support by soil nailing. The investigation included design of excavation supports by the two aforementioned systems for fifteen actual excavations, the majority of which were accomplished in the Louisville, Kentucky area. The design was optimized to arrive at minimum cost solutions. In all cases, the soil nailing system was much less costly than the conventional system. Several factors appeared to make soil nailing more economical than conventional retention systems, if deformations and settlement of soil nailing systems can be tolerated: lower …


Stereoscopic Vision In Vehicle Navigation., Behnoush Abdollahi 1986- Aug 2011

Stereoscopic Vision In Vehicle Navigation., Behnoush Abdollahi 1986-

Electronic Theses and Dissertations

Traffic sign (TS) detection and tracking is one of the main tasks of an autonomous vehicle which is addressed in the field of computer vision. An autonomous vehicle must have vision based recognition of the road to follow the rules like every other vehicle on the road. Besides, TS detection and tracking can be used to give feedbacks to the driver. This can significantly increase safety in making driving decisions. For a successful TS detection and tracking changes in weather and lighting conditions should be considered. Also, the camera is in motion, which results in image distortion and motion blur. …


A Water Distribution And Treatment Simulation For Testing Cyber Security Enhancements For Water Sector Scada Systems., Justin Robert Adams Jul 2011

A Water Distribution And Treatment Simulation For Testing Cyber Security Enhancements For Water Sector Scada Systems., Justin Robert Adams

Electronic Theses and Dissertations

Supervisory control and data acquisition (SCADA) systems are used by many critical infrastructures including electric power production and distribution, water and waste water treatment, rail transportation, and gas and oil distribution. Originally isolated proprietary systems, SCADA systems are increasingly connected to enterprise networks and the Internet and today use commercial hardware and software. As a result SCADA systems now face serious cyber-security threats. The need for testing and evaluation of developed cyber-security solutions presents a challenge since evaluation on actual systems is usually not possible and building complete physical testbeds is costly. This thesis presents the design and development of …


Development Of Wearable Sensors For Body Joint Angle Measurement, Saba Bakhshi Khayani Jun 2011

Development Of Wearable Sensors For Body Joint Angle Measurement, Saba Bakhshi Khayani

Electronic Theses and Dissertations

This thesis presents the development of three different methods for body joint angle measurement using wearable sensors. Continuous monitoring of patients' movements and activities has recently become one of the active research areas in the field of body sensor network and telehealth monitoring. For many medical and rehabilitation applications, a continuous monitor of the patients' daily activities at home without visiting the hospital is desirable. This type of monitoring is beneficial for the therapists and physicians as it does not require patients' physical presence. Traditionally, measuring the range of motion (ROM) is performed in hospitals by utilizing standard tools such …


Wired For Business: The Roebling Story., Kelley Marie Hatch-Draper May 2011

Wired For Business: The Roebling Story., Kelley Marie Hatch-Draper

Electronic Theses and Dissertations

John Augustus Roebling, a classically educated civil engineer and young Hegelian, immigrated to America in 1831 in search of freedom from a repressive political system that afforded him no opportunity for advancement. Arriving in the midst of the American market revolution, his dream of establishing an agrarian farming colony changed in response to societal transformations resulting from mechanization and the rise of industry. Within forty years, Roebling achieved fame as a canal engineer and bridge designer while establishing the American wire rope industry. Without Roebling's innovation in wire-rope, modern suspension bridges, high-rise elevators, construction cranes, and cable cars would not …


Cfd Modeling Of Entrance And Exit Geometries Of A Wind Speed Accelerator., David Russ May 2011

Cfd Modeling Of Entrance And Exit Geometries Of A Wind Speed Accelerator., David Russ

Electronic Theses and Dissertations

Current wind power technology is not economically feasible throughout most of the United States due to low average wind speeds. A design for a small-scale wind concentrator device suitable for use in areas of low wind velocity was tested using computational fluid dynamics (CFD). Using a novel approach, the device seeks to accelerate incoming air above minimum velocities required for economical power generation. The novel approach employs a funnel shaped inlet with relief vents along the circumference, so as to alleviate backpressure. Both inlet and outlet sections utilize funnel shapes with both parabolic and hyperbolic regions. All geometry and mesh …


Solar Power System Modeling And Performance Analysis, Jiaqi Wang Jan 2011

Solar Power System Modeling And Performance Analysis, Jiaqi Wang

Electronic Theses and Dissertations

At present the main source of our power and energy needs are from fossil fuel; almost all transportation tools and nearly 70% of electrical power are produced by fossil fuel. But unfortunately these materials are limited in our planet, with obvious drawback such as pollution. So looking for new kinds of energy supply is an urgent matter. Solar-powered photovoltaic system provides a clean energy solution to this problem. It is developing fast all over the world in terms of both research work and actual applications. It is estimated that the power supplied by solar energy can provide 10 percent of …


Simulation, Application, And Resilience Of An Organic Neuromorphic Architecture, Made With Organic Bistable Devices And Organic Field Effect Transistors, Robert A. Nawrocki Jan 2011

Simulation, Application, And Resilience Of An Organic Neuromorphic Architecture, Made With Organic Bistable Devices And Organic Field Effect Transistors, Robert A. Nawrocki

Electronic Theses and Dissertations

This thesis presents work done simulating a type of organic neuromorphic architecture, modeled after Artificial Neural Network, and termed Synthetic Neural Network, or SNN. The first major contribution of this thesis is development of a single-transistor-single-organic-bistable-device-per-input circuit that approximates behavior of an artificial neuron. The efficacy of this design is validated by comparing the behavior of a single synthetic neuron to that of an artificial neuron as well as two examples involving a network of synthetic neurons. The analysis utilizes electrical characteristics of polymer electronic elements, namely Organic Bistable Device and Organic Field Effect Transistor, created in the laboratory at …


Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar Jan 2011

Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar

Electronic Theses and Dissertations

Highly sensitive biosensors capable of detecting and characterizing smallest quantities of cellular and molecular targets are needed in pharmaceutical and medical diagnostics industries. In this work, the importance of biological target recognition specifically proteins through microarray technologies has been discussed and the most successful tools and techniques have been studied. Moreover, a thermally actuated Micro Electro-Mechanical Systems (MEMS) resonator has been demonstrated and fabricated in this work as an accurate, reliable and low cost biotechnology tool. As a proof of concept, amine to epoxide coupling of octadecylamine to functionalized silicon dioxide surface have been shown through resonator frequency monitoring. The …


Video Stabilization Using Sift Features, Fuzzy Clustering, And Kalman Filtering, Kevin Veon Jan 2011

Video Stabilization Using Sift Features, Fuzzy Clustering, And Kalman Filtering, Kevin Veon

Electronic Theses and Dissertations

Video stabilization removes unwanted motion from video sequences, often caused by vibrations or other instabilities. This improves video viewability and can aid in detection and tracking in computer vision algorithms. We have developed a digital video stabilization process using scale-invariant feature transform (SIFT) features for tracking motion between frames. These features provide information about location and orientation in each frame. The orientation information is generally not available with other features, so we employ this knowledge directly in motion estimation. We use a fuzzy clustering scheme to separate the SIFT features representing camera motion from those representing the motion of moving …


An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker Jan 2011

An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker

Electronic Theses and Dissertations

Class I (kg) autonomous helicopters are becoming increasingly popular for a wide range of non-military applications such as, surveillance, reconnaissance, traffic monitoring, emergency response, agricultural spraying, and many other "eye in the sky" missions. However, an efficient landing/takeoff platform with refueling/recharging capabilities has not yet been developed to increase the endurance and decrease the cost for Class I helicopters.

This dissertation presents a three-prong approach for increasing the range and endurance of Class I autonomous helicopters, which will then spur demand by non-military organizations wanting to take advantage of such capabilities and, therefore, drop their price. The proposed Intelligent Self-Leveling …


High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz Jan 2011

High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz

Electronic Theses and Dissertations

Over the past decades there has been a great deal of research on developing high frequency micromechanical resonators. As the two most common and conventional MEMS resonators, piezoelectric and electrostatic resonators have been at the center of attention despite having some drawbacks. Piezoelectric resonators provide low impedances that make them compatible with other low impedance electronic components, however they have low quality factors and complicated fabrication processes. In case of electrostatic resonators, they have higher quality factors but the need for smaller transductions gaps complicates their fabrication process and causes squeezed film damping in Air. In addition, the operation of …


Hybrid Sensing And Adaptive Control For Direct Brain Actuation Of Artificial Limbs, Christopher Aasted Jan 2011

Hybrid Sensing And Adaptive Control For Direct Brain Actuation Of Artificial Limbs, Christopher Aasted

Electronic Theses and Dissertations

Developing a non-invasive direct brain control of artificial limbs is both challenging and desirable. Such a sensory and control system, if successful, will have a profound impact on the disabled. In this dissertation, we present the design and development of a non-invasive, hybrid sensory system, which uses near-infrared spectroscopy (NIRS) and electroencephalography (EEG) to measure brain activity with simultaneous electromyography (EMG) to provide feedback data in a healthy limb. Through the combination of these sensory techniques, we have successfully trained a control system capable of mapping brain activity onto muscle actuation. The design of a control algorithm capable of automatic …


Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino Jan 2011

Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino

Electronic Theses and Dissertations

The need for cleaner and more fuel efficient means to produce electricity is growing steadily. Advancements in cooling technologies contribute to the improvements in turbine efficiency and are used for gas turbines and for power generation in automotive, aviation, as well as in naval applications, and many more. Studies introducing turbulators on walls of internal cooling channels, which can be applied to hot gas components and in recuperative heat exchangers, have been reviewed for their ability to promote heat transfer in the channel while observing pressure loss caused by adding the features. Several types of turbulators have been studied; ribs, …


Development Of A Cognitive Work Analysis Framework Tutorial Using Systems Modeling Language, Wilfred Henry Wells Jan 2011

Development Of A Cognitive Work Analysis Framework Tutorial Using Systems Modeling Language, Wilfred Henry Wells

Electronic Theses and Dissertations

At the present time, most systems engineers do not have access to cognitive work analysis information or training in terms they can understand. This may lead to a disregard of the cognitive aspect of system design. The impact of this issue is system requirements that do not account for the cognitive strengths and limitations of users. Systems engineers cannot design effective decision support systems without defining cognitive work requirements. In order to improve system requirements, integration of cognitive work requirements into the systems engineering process has to be improved. One option to address this gap is the development of a …


Harmony Oriented Architecture, Kyle A. Martin Jan 2011

Harmony Oriented Architecture, Kyle A. Martin

Electronic Theses and Dissertations

This thesis presents Harmony Oriented Architecture: a novel architectural paradigm that applies the principles of Harmony Oriented Programming to the architecture of scalable and evolvable distributed systems. It is motivated by research on Ultra Large Scale systems that has revealed inherent limitations in human ability to design large-scale software systems that can only be overcome through radical alternatives to traditional object-oriented software engineering practice that simplifies the construction of highly scalable and evolvable system. HOP eschews encapsulation and information hiding, the core principles of objectoriented design, in favor of exposure and information sharing through a spatial abstraction. This helps to …


Multilayered Planar Periodic Subwavelength Microstructures For Generating And Detecting Circularly Polarized Thermal Infrared Radiation, Samuel Lanning Wadsworth Jan 2011

Multilayered Planar Periodic Subwavelength Microstructures For Generating And Detecting Circularly Polarized Thermal Infrared Radiation, Samuel Lanning Wadsworth

Electronic Theses and Dissertations

Generation and detection of circularly-polarized (CP) radiation in the 8- to 12-μm band of the infrared (IR) spectrum is crucial for polarization sensing and imaging scenarios. There is very little naturally occurring CP radiation in the long-wave IR band, so that useful functionalities may be obtained by exploiting preferential radiation and transmission characteristics of engineered metamaterials. Conventional CP devices in the IR utilize birefringent crystals, which are typically bulky and expensive to manufacture. The operation of these devices is generally optimized at a single wavelength. Imaging in the long-wave IR is most often broadband, so that achromatic CP-device behavior is …


Optimal Attitude Control Management For A Cubesat, Michael James Develle Jan 2011

Optimal Attitude Control Management For A Cubesat, Michael James Develle

Electronic Theses and Dissertations

CubeSats have become popular among universities, research organizations, and government agencies due to their low cost, small size, and light weight. Their standardized configurations further reduce the development time and ensure more frequent launch opportunities. Early cubesat missions focused on hardware validation and simple communication missions, with little requirement for pointing accuracy. Most of these used magnetic torque rods or coils for attitude stabilization. However, the intrinsic problems associated with magnetic torque systems, such as the lack of three-axis control and low pointing accuracy, make them unsuitable for more advanced missions such as detailed imaging and on-orbit inspection. Threeaxis control …