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Linear Mode Cmos Compatible P-N Junction Avalanche Photodiode For Smart-Lighting Applications, Md. Mottaleb Hossain Sep 2015

Linear Mode Cmos Compatible P-N Junction Avalanche Photodiode For Smart-Lighting Applications, Md. Mottaleb Hossain

Optical Science and Engineering ETDs

There is a need in emerging smart lighting concepts for a high-speed sensing capability to enable adaptive lighting (smart spaces) and visible light communication. One approach to address this need is to design and manufacture a novel complementary-metal—oxide—semiconductor (CMOS) compatible, cost-effective detector array and readout circuit (ROIC) that incorporates integrated waveguide detectors and avalanche photodiodes (APDs). This thesis focuses on the APD design and fabrication component of the sensing capability required by smart-lighting systems. Silicon CMOS compatible APDs are expected to provide high-speed and high-sensitivity sensors in terms of simplicity of design, low power consumption and cost-effectiveness for smart-lighting applications. …


Modified Inverse First-Order Reliability Method (I-Form) For Predicting Extreme Sea States, Aubrey Celia Eckert-Gallup Sep 2015

Modified Inverse First-Order Reliability Method (I-Form) For Predicting Extreme Sea States, Aubrey Celia Eckert-Gallup

Civil Engineering ETDs

Environmental contours describing extreme sea states are generated as the input for numerical or physical model simulations as a part of the standard current practice for designing marine structures to survive extreme sea states. Such environmental contours are characterized by combinations of significant wave height (Hs) and energy period (Te) or peak period (Tp) values calculated for a given recurrence interval using a set of data based on hindcast simulations or buoy observations over a sufficient period of record. The use of the inverse first-order reliability method (I-FORM) is standard design practice for generating environmental contours. This thesis develops enhanced …


Precise Characterization And Investigation Of Laser Cooling In Iii-V Compound Semiconductors, Chengao Wang Sep 2015

Precise Characterization And Investigation Of Laser Cooling In Iii-V Compound Semiconductors, Chengao Wang

Optical Science and Engineering ETDs

The physics and engineering issues associated with laser cooling of III-V compound semiconductors, in particular GaAs double heterostructures (DHS), are theoretically and experimentally investigated. This research addresses the key concepts of external quantum efficiency (EQE) and parasitic background absorption in a semiconductor laser cooler. The external quantum efficiency describes how well recombination radiation is removed from the cooling device and is precisely measured by All-optical Scanning Laser Calorimetry (ASLC). Using this technique, a record external quantum efficiency of 99.5% has been obtained with a GaAs laser cooler held at 100 K. However, high background absorption has hindered the observation of …


The Electroreduction Of Carbon Dioxide On Porous Copper Nanoparticles, Monica Alisa Padilla Jun 2015

The Electroreduction Of Carbon Dioxide On Porous Copper Nanoparticles, Monica Alisa Padilla

Chemical and Biological Engineering ETDs

Copper nanoparticles of porous, controlled structure were synthesized using the sacrificial support method (SSM). The precursor weight percent (wt%) of copper (Cu) and fumed silica (EH-5) was varied to determine the optimum ratio for this material. The precursors were reduced at i) 350°C in a 7% H2 atmosphere and ii) at 250°C in a 100% H2 atmosphere. The specific surface areas of the nanoparticles was measured by Brunauer-Emmett-Teller N2 absorption. The morphologies and widths of the nanoparticles were confirmed by imaging the nanoparticles by scanning electron microscopy (SEM). The bulk composition of the nanoparticles was determined by X-ray diffraction (XRD). …


Variation Tolerant Energy Efficient Design For Ultra Low Voltage Digital Circuits, Preyom Dey Jun 2015

Variation Tolerant Energy Efficient Design For Ultra Low Voltage Digital Circuits, Preyom Dey

Electrical and Computer Engineering ETDs

The demand of extremely long battery life for electronic devices is the driving force for modern semiconductor industry in recent years. Supply voltage scaling offers a promising solution for this matter. To control the energy consumption and limit the power dissipation of a circuit, supply voltage should be scaled continually. Threshold voltage should also be reduced to sustain performance and reliability. This scaling of supply and threshold voltage imposes several bottlenecks in ultra-low voltage circuit design. One of the major barriers for ultra-low voltage design is the performance deviation of digital circuit due to supply voltage variation. As technology scales, …


Multispectral Metamaterial Detectors For Smart Imaging, John A. Montoya Jun 2015

Multispectral Metamaterial Detectors For Smart Imaging, John A. Montoya

Electrical and Computer Engineering ETDs

The ability to produce a high quality infrared image has significantly improved since its initial development in the 1950s. The first generation consisted of a single pixel that required a two-dimensional raster scan to produce an image. The second generation comprised of a linear array of pixels that required a mechanical sweep to produce an image. The third generation utilizes a two-dimensional array of pixels to eliminate the need for a mechanical sweep. Third generation imaging technology incorporates pixels with single color or broadband sensitivity, which results in 'black and white' images. The research presented in this dissertation focuses on …


Three-Dimensional Imaging Using A Novel Rotating Point Spread Function Imager, Rakesh Kumar Jun 2015

Three-Dimensional Imaging Using A Novel Rotating Point Spread Function Imager, Rakesh Kumar

Optical Science and Engineering ETDs

The capability to achieve three-dimensional (3D) imaging in a single snapshot is a highly coveted goal for the imaging community. To be able to extend the depth-of-field while simultaneously encoding depth in the point spread function (PSF) itself allows an imaging solution which is less time consuming and less data intensive than the inefficient multiscan based conventional 3D imaging. Light-field cameras also achieve 3D imaging in a snapshot, but at the cost of greatly reduced resolution. Phase mask based depth encoding solutions have been proposed by other groups, but they all suffer from a relatively smaller depth-of-field. Recently there has …


Communication-Theoretic Foundations For Optical Receivers Using Dynamically Biased Avalanche Photodiodes, Georges El-Howayek Jun 2015

Communication-Theoretic Foundations For Optical Receivers Using Dynamically Biased Avalanche Photodiodes, Georges El-Howayek

Electrical and Computer Engineering ETDs

To meet the demands of the exponential growth in video, voice, data and mobile device traffic over the internet, the telecommunication industry has been moving toward higher speed protocols such as 40-Gb/s and 100-Gb/s. Operations at such high speeds require detectors with optimized internal gain (leading to high sensitivity) to reduce cost. Avalanche photodiodes (APDs) are commonly used photodetectors in many high-speed optical receivers due to their internal optoelectronic gain, which allows the photogenerated current to dominate the thermal noise without the need for optical pre-amplification of the received optical signal. However, the long avalanche buildup time associated with APDs, …


Efficacy Of A Magnetic Drug Delivery System And Development Of An Orthotopic Lung Tumor Imaging Model, Amber Mcbride Jan 2015

Efficacy Of A Magnetic Drug Delivery System And Development Of An Orthotopic Lung Tumor Imaging Model, Amber Mcbride

Nanoscience and Microsystems ETDs

The aim of this work was the development of a novel drug delivery vehicle termed nano-in-microparticles (NIMs) to evaluate the magnetic-field dependent targeting of dry powder NIMs administered endotracheally using an ex vivo and in vivo rodent model. NIMs are a novel dry powder drug delivery vehicle containing 70% lactose (w/w), 20% SPIONs (w/w) and 10% fluorescent nanospheres (w/w). Mice were insufflated with NIMs delivery vehicle in the presence of magnetic field dependent targeting to the left ventral lung after thoracotomy; controls were insufflated with the NIMs in the absence of magnetic field dependent targeting. Quantification of deposition of the …