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Full-Text Articles in Engineering

High Resolution Time-Resolved Imaging System In The Vacuum Ultraviolet Region, Yuseong Jang Jan 2014

High Resolution Time-Resolved Imaging System In The Vacuum Ultraviolet Region, Yuseong Jang

Electronic Theses and Dissertations

High-power debris-free vacuum ultraviolet (VUV) light sources have applications in several scientific and engineering areas, such as high volume manufacturing lithography and inspection tools in the semiconductor industry, as well as other applications in material processing and photochemistry. For the past decades, the semiconductor industry has been driven by what is called "Moore's Law". The entire semiconductor industry relies on this rule, which requires chip makers to pack transistors more tightly with every new generation of chips, shrinking the size of transistors. The ability to solve roadmap challenges is, at least partly, proportional to our ability to measure them. The …


High Performance Three-Dimensional Display Based On Polymer-Stabilized Blue Phase Liquid Crystal, Yifan Liu Jan 2014

High Performance Three-Dimensional Display Based On Polymer-Stabilized Blue Phase Liquid Crystal, Yifan Liu

Electronic Theses and Dissertations

Autostereoscopic 2D/3D (two-dimension/three-dimension) switchable display has been attracting great interest in research and practical applications for several years. Among different autostereoscopic solutions, direction-multiplexed 3D displays based on microlens array or parallax barrier are viewed as the most promising candidates, due to their compatibility with conventional 2D display technologies. These 2D/3D switchable display system designs rely on fast switching display panels and photonics devices, including adaptive focus microlens array and switchable slit array. Polymer-stabilized blue phase liquid crystal (PS-BPLC) material provides a possible solution to meet the aforementioned fast response time requirement. However, present display and photonic devices based on blue …


Holographic Recording And Applications Of Multiplexed Volume Bragg Gratings In Photo-Thermo-Refractive Glass, Daniel Ott Jan 2014

Holographic Recording And Applications Of Multiplexed Volume Bragg Gratings In Photo-Thermo-Refractive Glass, Daniel Ott

Electronic Theses and Dissertations

Recent developments in holographic recording of volume Bragg gratings (VBGs) in photo-thermo-refractive (PTR) glass have demonstrated their utility as components in high power laser systems for spectral narrowing, transverse mode control, beam combining, and pulse stretching/compression. VBG structures are capable of diffracting incident light into a single diffraction order with high efficiency given the Bragg condition is met. The Bragg condition depends on both the wavelength and angle of the incident light making VBGs useful for filtering and manipulating both the wavelength and angular spectrum of a source. This dissertation expands upon previous research in PTR VBGs by investigating multiplexed …


Entangled Photon Pairs In Disordered Photonic Lattices, Lane Martin Jan 2014

Entangled Photon Pairs In Disordered Photonic Lattices, Lane Martin

Electronic Theses and Dissertations

Photonic lattices consisting of arrays of evanescently coupled waveguides fabricated with precisely controlled parameters have enabled the study of discrete optical phenomena, both classical and quantum, and the simulation of other physical phenomena governed by the same dynamics. In this dissertation, I have experimentally demonstrated transverse Anderson localization of classical light in arrays with off-diagonal coupling disorder and investigated theoretically and experimentally the propagation of entangled photon pairs through such disordered systems. I discovered a new phenomenon, Anderson co-localization, in which a spatially entangled photon pair in a correlated transversally extended state localizes in the correlation space, though neither photon …


Injection-Locked Vertical Cavity Surface Emitting Lasers (Vcsels) For Optical Arbitrary Waveform Generation, Sharad Bhooplapur Jan 2014

Injection-Locked Vertical Cavity Surface Emitting Lasers (Vcsels) For Optical Arbitrary Waveform Generation, Sharad Bhooplapur

Electronic Theses and Dissertations

Complex optical pulse shapes are typically generated from ultrashort laser pulses by manipulating the optical spectrum of the input pulses. This generates complex but periodic time-domain waveforms. Optical Arbitrary Waveform Generation (OAWG) builds on the techniques of ultrashort pulse-shaping, with the goal of making non-periodic, truly arbitrary optical waveforms. Some applications of OAWG are coherently controlling chemical reactions on a femtosecond time scale, improving the performance of LADAR systems, high-capacity optical telecommunications and ultra wideband signals processing. In this work, an array of Vertical Cavity Surface Emitting Lasers (VCSELs) are used as modulators, by injection-locking each VCSEL to an individual …


Nonlinear Integrated Photonics On Silicon And Gallium Arsenide Substrates, Jichi Ma Jan 2014

Nonlinear Integrated Photonics On Silicon And Gallium Arsenide Substrates, Jichi Ma

Electronic Theses and Dissertations

Silicon photonics is nowadays a mature technology and is on the verge of becoming a blossoming industry. Silicon photonics has also been pursued as a platform for integrated nonlinear optics based on Raman and Kerr effects. In recent years, more futuristic directions have been pursued by various groups. For instance, the realm of silicon photonics has been expanded beyond the well-established near-infrared wavelengths and into the mid-infrared (3 - 5 µm). In this wavelength range, the omnipresent hurdle of nonlinear silicon photonics in the telecommunication band, i.e., nonlinear losses due to two-photon absorption, is inherently nonexistent. With the lack of …


Learning To Grasp Unknown Objects Using Weighted Random Forest Algorithm From Selective Image And Point Cloud Feature, Md Shahriar Iqbal Jan 2014

Learning To Grasp Unknown Objects Using Weighted Random Forest Algorithm From Selective Image And Point Cloud Feature, Md Shahriar Iqbal

Electronic Theses and Dissertations

This method demonstrates an approach to determine the best grasping location on an unknown object using Weighted Random Forest Algorithm. It used RGB-D value of an object as input to find a suitable rectangular grasping region as the output. To accomplish this task, it uses a subspace of most important features from a very high dimensional extensive feature space that contains both image and point cloud features. Usage of most important features in the grasping algorithm has enabled the system to be computationally very fast while preserving maximum information gain. In this approach, the Random Forest operates using optimum parameters …


Transparent Oxide Semiconductor Gate Based Mosfets For Sensor Applications, Ashwin Kumar Saikumar Jan 2014

Transparent Oxide Semiconductor Gate Based Mosfets For Sensor Applications, Ashwin Kumar Saikumar

Electronic Theses and Dissertations

Starting from small scale laboratories to the highly sophisticated industrial facilities, monitoring and control forms the most integral part. In order to perform this continuous monitoring we require an interface, that would operate between the system and its processing conditions and in turn which facilitates us to act accordingly. This interface is called as a sensor. There are various types of sensors available which have wide range of functionality in various different fields. The use of transparent conducting oxide (TCO) in the field of sensor applications has increased and has been the subject of extensive research. Good electrical properties, good …


Practical Issues In Gpram Development, Yin Li Jan 2014

Practical Issues In Gpram Development, Yin Li

Electronic Theses and Dissertations

In this thesis, two parts of practical issues in the GPRAM system design are included. The first part is the coding part. The sum-product decoding algorithm of LDPC codes has been refined to fit for the GPRAM hardware implementation. As we all know, communication channel has noise. The noise in telecom system is different from that in GPRAM systems. So the noise should be handled well in the GPRAM design. A noise look-up table was created for FPGA and those noises in the table are quantized. The second part of the thesis is to convert perfect images in video stream …


On Kernel-Base Multi-Task Learning, Cong Li Jan 2014

On Kernel-Base Multi-Task Learning, Cong Li

Electronic Theses and Dissertations

Multi-Task Learning (MTL) has been an active research area in machine learning for two decades. By training multiple relevant tasks simultaneously with information shared across tasks, it is possible to improve the generalization performance of each task, compared to training each individual task independently. During the past decade, most MTL research has been based on the Regularization-Loss framework due to its flexibility in specifying various types of information sharing strategies, the opportunity it offers to yield a kernel-based methods and its capability in promoting sparse feature representations. However, certain limitations exist in both theoretical and practical aspects of Regularization-Loss-based MTL. …


Treatment-Specific Approaches For Analysis And Control Of Left Ventricular Assist Devices, George Faragallah Jan 2014

Treatment-Specific Approaches For Analysis And Control Of Left Ventricular Assist Devices, George Faragallah

Electronic Theses and Dissertations

A Left Ventricular Assist Device (LVAD) is a mechanical pump that helps patients with heart failure conditions. This rotary pump works in parallel to the ailing heart and provides an alternative path for blood flow from the weak left ventricle to the aorta. The LVAD is controlled by the power supplied to the pump motor. An increase in the pump motor power increases the pump speed and the pump flow. The LVAD is typically controlled at a fixed setting of pump power. This basically means that the controller does not react to any change in the activity level of the …


Photonic Filtering For Applications In Microwave Generation And Metrology, Marcus Bagnell Jan 2014

Photonic Filtering For Applications In Microwave Generation And Metrology, Marcus Bagnell

Electronic Theses and Dissertations

This work uses the photonic filtering properties of Fabry-Perot etalons to show improvements in the electrical signals created upon photodetection of the optical signal. First, a method of delay measurement is described which uses multi-heterodyne detection to find correlations in white light signals at 20 km of delay to sub millimeter resolution. By filtering incoming white light with a Fabry-Perot etalon, the pseudo periodic signal is suitable for measurement by combining and photodetecting it with an optical frequency comb. In this way, optical data from a large bandwidth can be downconverted and sampled on low frequency electronics. Second, a high …


Multifunctional, Multimaterial Particle Fabrication Via An In-Fiber Fluid Instability, Joshua Kaufman Jan 2014

Multifunctional, Multimaterial Particle Fabrication Via An In-Fiber Fluid Instability, Joshua Kaufman

Electronic Theses and Dissertations

Spherical micro- and nano-particles have found widespread use in many various applications from paint to cosmetics to medicine. Due to the multiplicity of desired particle material(s), structure, size range, and functionality, many approaches exist for generating such particles. Bottom-up methods such as chemical synthesis have a high yield and work with a wide range of materials; however, these processes typically lead to large polydispersity and cannot produce structured particles. Top-down approaches such as microfluidics overcome the polydispersity issue and may produce a few different structures in particles, but at lower rates and only at the micro-scale. A method that can …


Large Area Conformal Infrared Frequency Selective Surfaces, Jeffrey D'Archangel Jan 2014

Large Area Conformal Infrared Frequency Selective Surfaces, Jeffrey D'Archangel

Electronic Theses and Dissertations

Frequency selective surfaces (FSS) were originally developed for electromagnetic filtering applications at microwave frequencies. Electron-beam lithography has enabled the extension of FSS to infrared frequencies; however, these techniques create sample sizes that are seldom appropriate for real world applications due to the size and rigidity of the substrate. A new method of fabricating large area conformal infrared FSS is introduced, which involves releasing miniature FSS arrays from a substrate for implementation in a coating. A selective etching process is proposed and executed to create FSS particles from crossed-dipole and square-loop FSS arrays. When the fill-factor of the particles in the …


Integrated Microwave Resonator/Antenna Structures For Sensor And Filter Applications, Haitao Cheng Jan 2014

Integrated Microwave Resonator/Antenna Structures For Sensor And Filter Applications, Haitao Cheng

Electronic Theses and Dissertations

This dissertation presents design challenges and promising solutions for temperature and pressure sensors which are highly desirable for harsh-environment applications, such as turbine engines. To survive the harsh environment consisting of high temperatures above 1000°C, high pressures around 300 psi, and corrosive gases, the sensors are required to be robust both electrically and mechanically. In addition, wire connection of the sensors is a challenging packaging problem, which remains unresolved as of today. In this dissertation, robust ceramic sensors are demonstrated for both high temperature and pressure measurements. Also, the wireless sensors are achieved based on microwave resonators. Two types of …


Investigation Of Dual-Stage High Efficiency And Density Micro Inverter For Solar Application, Lin Chen Jan 2014

Investigation Of Dual-Stage High Efficiency And Density Micro Inverter For Solar Application, Lin Chen

Electronic Theses and Dissertations

Module integrated converters (MIC), also called micro inverter, in single phase have witnessed recent market success due to unique features (1) improved energy harvest, (2) improved system efficiency, (3) lower installation costs, (4) plug-N-play operation, (5) and enhanced flexibility and modularity. The MIC sector has grown from a niche market to mainstream, especially in the United States. Due to the fact that two-stage architecture is commonly used for single phase MIC application. A DC-DC stage with maximum power point tracking to boost the output voltage of the Photovoltaic (PV) panel is employed in the first stage, DC-AC stage is used …


Laser Filamentation - Beyond Self-Focusing And Plasma Defocusing, Khan Lim Jan 2014

Laser Filamentation - Beyond Self-Focusing And Plasma Defocusing, Khan Lim

Electronic Theses and Dissertations

Laser filamentation is a highly complex and dynamic nonlinear process that is sensitive to many physical parameters. The basic properties that define a filament consist of (i) a narrow, high intensity core that persists for distances much greater than the Rayleigh distance, (ii) a low density plasma channel existing within the filament core, and (iii) a supercontinuum generated over the course of filamentation. However, there remain many questions pertaining to how these basic properties are affected by changes in the conditions in which the filaments are formed; that is the premise of the work presented in this dissertation. To examine …


Multimaterial Fibers In Photonics And Nanotechnology, Guangming Tao Jan 2014

Multimaterial Fibers In Photonics And Nanotechnology, Guangming Tao

Electronic Theses and Dissertations

Recent progress in combing multiple materials with distinct optical, electronic, and thermomechanical properties monolithically in a kilometer-long fiber drawn from a preform offers unique multifunctionality at a low cost. A wide range of unique in-fiber devices have been developed in fiber form-factor using this strategy. Here, I summary my recent results in this nascent field of 'multimaterial fibers'. I will focus on my achievements in producing robust infrared optical fibers and in appropriating optical fiber production technology for applications in nanofabrication. The development of optical components suitable for the infrared (IR) is crucial for applications in this spectral range to …


Techniques For Characterization Of Third Order Optical Nonlinearities, Manuel Ferdinandus Jan 2014

Techniques For Characterization Of Third Order Optical Nonlinearities, Manuel Ferdinandus

Electronic Theses and Dissertations

This dissertation describes the development of novel techniques for characterization of nonlinear properties of materials. The dissertation is divided into two parts, a background and theory section and a technique development section. In the background and theory section we explain the origins of the nonlinear optical response of materials across many different spatial and temporal scales. The mechanisms that we are most interested in are the electronic nuclear and reorientational responses, which occur on the range of sub-femtosecond to several picoseconds. The electronic mechanism is due to the electrons of a material experiencing a non-parabolic potential well due a strong …


Advanced Liquid Crystal Materials For Display And Photonic Applications, Yuan Chen Jan 2014

Advanced Liquid Crystal Materials For Display And Photonic Applications, Yuan Chen

Electronic Theses and Dissertations

Thin-film-transistor (TFT) liquid crystal display (LCD) has been widely used in smartphones, pads, laptops, computer monitors, and large screen televisions, just to name a few. A great deal of effort has been delved into wide viewing angle, high resolution, low power consumption, and vivid color. However, relatively slow response time and low transmittance remain as technical challenges. To improve response time, several approaches have been developed, such as low viscosity liquid crystals, overdrive and undershoot voltage schemes, thin cell gap with a high birefringence liquid crystal, and elevated temperature operation. The state-of-the-art gray-to-gray response time of a nematic LC device …


Generation And Characterization Of Sub-70 Isolated Attosecond Pulses, Qi Zhang Jan 2014

Generation And Characterization Of Sub-70 Isolated Attosecond Pulses, Qi Zhang

Electronic Theses and Dissertations

Dynamics occurring on microscopic scales, such as electronic motion inside atoms and molecules, are governed by quantum mechanics. However, the Schroedinger equation is usually too complicated to solve analytically for systems other than the hydrogen atom. Even for some simple atoms such as helium, it still takes months to do a full numerical analysis. Therefore, practical problems are often solved only after simplification. The results are then compared with the experimental outcome in both the spectral and temporal domain. For accurate experimental comparison, temporal resolution on the attosecond scale is required. This had not been achieved until the first demonstration …


Conae Microwave Radiometer (Mwr) Counts To Brightness Temperature Algorithm, Zoubair Ghazi Jan 2014

Conae Microwave Radiometer (Mwr) Counts To Brightness Temperature Algorithm, Zoubair Ghazi

Electronic Theses and Dissertations

This dissertation concerns the development of the MicroWave Radiometer (MWR) brightness temperature (Tb) algorithm and the associated algorithm validation using on-orbit MWR Tb measurements. This research is sponsored by the NASA Earth Sciences Aquarius Mission, a joint international science mission, between NASA and the Argentine Space Agency (Comision Nacional de Actividades Espaciales, CONAE). The MWR is a CONAE developed passive microwave instrument operating at 23.8 GHz (K-band) H-pol and 36.5 GHz (Ka-band) H- and V-pol designed to complement the Aquarius L-band radiometer/scatterometer, which is the prime sensor for measuring sea surface salinity (SSS). MWR measures the Earth's brightness temperature and …


Lp Fiber Mode Converters Using Holographic Phase Mask In Photo-Thermo-Refractive Glass, Aniket Patil Jan 2014

Lp Fiber Mode Converters Using Holographic Phase Mask In Photo-Thermo-Refractive Glass, Aniket Patil

Electronic Theses and Dissertations

In this study, an investigation was undertaken to research the use of holographic phase masks (HPMs) in photo-thermo-refractive (PTR) glass as mode converters for linearly polarized (LP) fiber modes. A Spatial Light Modulator (SLM) was used to generate higher-order transverse fiber modes LPm,n. Under proper incidence condition on the holographic device, LPm,n modes are diffracted and simultaneously converted into higher order or lower order LP modes. The process was analyzed by imaging the far field on a CCD camera. It is demonstrated that using this novel method of converting transverse fiber modes several combinations of LP modes can be converted …


Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad Jan 2014

Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad

Electronic Theses and Dissertations

One of the most intriguing properties of light-matter interaction is the ability of an electromagnetic field to exert mechanical forces on polarizable objects. This phenomenon is a direct consequence of the fact that light carries momentum, which in turn can be transferred to matter. Mediated by scattering, this interaction usually manifests itself as a “pushing force” in the direction of beam propagation. However, it is possible to judiciously engineer these optical forces, either by tailoring particle polarizability, and/or by structuring the incident light field. As a simple example, a tightly focused laser beam demonstrates strong gradient forces, which may attract …


Wireless Sensor Localization: Error Modeling And Analysis For Evaluation And Precision, Omar Ali Zargelin Jan 2014

Wireless Sensor Localization: Error Modeling And Analysis For Evaluation And Precision, Omar Ali Zargelin

Electronic Theses and Dissertations

Wireless sensor networks (WSNs) have shown promise in a broad range of applications. One of the primary challenges in leveraging WSNs lies in gathering accurate position information for the deployed sensors while minimizing power cost. In this research, detailed background research is discussed regarding existing methods and assumptions of modeling methods and processes for estimating sensor positions. Several novel localization methods are developed by applying rigorous mathematical and statistical principles, which exploit constraining properties of the physical problem in order to produce improved location estimates. These methods are suitable for one-, two-, and three-dimensional position estimation in ascending order of …


Design And Evaluation Of A Propulsion System For Small, Compact, Low-Speed Maneuvering Underwater Vehicles, Florence M. Mbithi Jan 2014

Design And Evaluation Of A Propulsion System For Small, Compact, Low-Speed Maneuvering Underwater Vehicles, Florence M. Mbithi

Electronic Theses and Dissertations

Underwater vehicles used to perform precision inspection and non-destructive evaluation in tightly constrained or delicate underwater environments must be small, have low-speed maneuverability and a smooth streamlined outer shape with no appendages. In this thesis, the design and analysis of a new propulsion system for such underwater vehicles is presented. It consists primarily of a syringe and a plunger driven by a linear actuator and uses different inflow and outflow nozzles to provide continuous propulsive force. A prototype of the proposed propulsion mechanism is built and tested. The practical utility and potential efficacy of the system is demonstrated and assessed …


Building Temperature Control With Intelligent Methods, Feng Zhang Jan 2014

Building Temperature Control With Intelligent Methods, Feng Zhang

Electronic Theses and Dissertations

Temperature control is important for both human comfort and the need in industry. In the thesis, two good intelligent control methods are compared to find their advantages and disadvantages. Matlab is used as the tool to make models and process calculations. The building model is one simple room in Akwesasne in New York State and the target is to keep the temperature indoor around 22 degree Centigrade from 12/29/2013 to 12/31/2013. Heat pump is used to provide or absorb heat. All data in the experiments is from JRibal Environmental eXchange network and PJM. The first method is fuzzy neural network …


Short-Term Load Forecasting Using Neural Network For Future Smart Grid Application, Jixuan Zheng Jan 2014

Short-Term Load Forecasting Using Neural Network For Future Smart Grid Application, Jixuan Zheng

Electronic Theses and Dissertations

Short-term load forecasting of power system has been a classic problem for a long time. Not merely it has been researched extensively and intensively, but also a variety of forecasting methods has been raised.

This thesis outlines some aspects and functions of smart meter. It also presents different policies and current statuses as well as future projects and objectives of SG development in several countries.

Then the thesis compares main aspects about latest products of smart meter from different companies.

Lastly, three types of prediction models are established in MATLAB to emulate the functions of smart grid in the short-term …


Fabrication And Application Of A Polymer Neuromorphic Circuitry Based On Polymer Memristive Devices And Polymer Transistors, Robert A. Nawrocki Jan 2014

Fabrication And Application Of A Polymer Neuromorphic Circuitry Based On Polymer Memristive Devices And Polymer Transistors, Robert A. Nawrocki

Electronic Theses and Dissertations

Neuromorphic engineering is a discipline that aims to address the shortcomings of today's serial computers, namely large power consumption, susceptibility to physical damage, as well as the need for explicit programming, by applying biologically-inspired principles to develop neural systems with applications such as machine learning and perception, autonomous robotics and generic artificial intelligence.

This doctoral dissertation presents work performed fabricating a previously developed type of polymer neuromorphic architecture, termed Polymer Neuromorphic Circuitry (PNC), inspired by the McCulloch-Pitts model of an artificial neuron. The major contribution of this dissertation is a development of processing techniques necessary to realize the Polymer Neuromorphic …


Optimized Image Compressed Sensing And Transmission Through Wireless Channels, Saheed Olanigan Jan 2014

Optimized Image Compressed Sensing And Transmission Through Wireless Channels, Saheed Olanigan

Electronic Theses and Dissertations

This thesis examines the robust behavior of quantized compressed sensing measurements during transmission through an additive white gaussian noise wireless channel. The poor rate-distortion performance that accompanies compressed sensing after applying quantization has led to several works in quantized compressed sensing. However, most of these works have less consideration of the effect of transmission channel on the resulting bit stream of the quantized compressed sensing measurements. For an additive white gaussian noise wireless channel model, the quantizer and bit energy signal-to-noise ratio determines the degree of the channel effect. This thesis explores the effect of quantization and channel noise during …