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2013

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Articles 6661 - 6690 of 7289

Full-Text Articles in Engineering

The Influence Of Socioeconomic Status And System Design On Child Passenger Safety, Donald Scott Burke Jan 2013

The Influence Of Socioeconomic Status And System Design On Child Passenger Safety, Donald Scott Burke

All ETDs from UAB

Motor vehicle collisions remain the number one cause of death for children in the United States, despite decades of prevention efforts led by safety experts and numerous private and government organizations. The overarching purpose of this research was to examine and compare the system safety factors that influence child passenger safety (CPS) with a particular focus on children living in poverty. The NASS-CDS and U.S. Census national databases were utilized to determine the effect of socioeconomic status on child occupant morbidity and mortality. The results of this analysis revealed for the first time, the disproportionate vulnerability of poor children in …


Energy Performance Evaluation Of Aac, Hulya Aybek Jan 2013

Energy Performance Evaluation Of Aac, Hulya Aybek

All ETDs from UAB

The U.S. building industry constitutes the largest consumer of energy (i.e., electricity, natural gas, petroleum) in the world. The building sector uses almost 41percent of the primary energy and approximately 72percent of the available electricity in the United States. As global energy-generating resources are being depleted at exponential rates, the amount of energy consumed and wasted cannot be ignored. Professionals concerned about the environment have placed a high priority on finding solutions that reduce energy consumption while maintaining occupant comfort. Sustainable design and the judicious combination of building materials comprise one solution to this problem. A future including sustainable energy …


In-Vivo Characterization Of Cone Photoreceptor Packing Density With Adaptive Optics Scanning Laser Ophthalmoscopy In Different Racial Groups, Ernesto Blanco Rivero Jan 2013

In-Vivo Characterization Of Cone Photoreceptor Packing Density With Adaptive Optics Scanning Laser Ophthalmoscopy In Different Racial Groups, Ernesto Blanco Rivero

All ETDs from UAB

Cone photoreceptors are one of the two types of essential light sensitive cells that initiate the visual process in the human retina. A normal database of the cone density of healthy eyes may provide an important measure for diagnosing retinal diseases that cause photoreceptor loss, for monitoring disease progression, and for evaluating treatment out-come. Recent studies revealed that the foveal pit morphology, retina thickness, retinal nerve fiber layer (RNFL) thickness, and optic nerve head structure significantly correlated with racial background. We hypothesize that the cone density may be also modified by racial background. To test this hypothesis, I used a …


Biocomposite Material Evaluation And Processing For Automotive Interior Components, Theresa Lee Sullins Jan 2013

Biocomposite Material Evaluation And Processing For Automotive Interior Components, Theresa Lee Sullins

All ETDs from UAB

There is growing demand for materials that are environmentally friendly and sustainable. One of the areas of focus right now is the transportation/automotive field where more energy efficient vehicles are needed to meet growing government regulations and to reduce the negative impacts on global air quality, human health and global climate. Several researchers are focusing on bio-based composites with natural fibers being the prime choice for fiber reinforced composites. The processing and characterization of 30 wt. % industrial hemp fiber reinforced PP composites for automotive interior components are discussed. The material was compounded by a twin screw and then processed …


Plga Nanospheres For Sustained Release Of Rifampicin, Alyssa Brianna Terry Jan 2013

Plga Nanospheres For Sustained Release Of Rifampicin, Alyssa Brianna Terry

All ETDs from UAB

Although Tuberculosis (TB) is often regarded as a disease of the past, it is still one of the leading killers of people worldwide. TB is caused by Mycobacterium tuberculosis, a bacterium that mostly infects the lungs but can also infect other organs throughout the body. One goal for TB treatment is to create a biocompatible, biodegradable drug delivery system that employs the use of multiple drugs while simultaneously relieving the patient from the burden of self-medicating. For this study, we optimized a procedure for making poly(lactic acid-co-glycolic acid) (PLGA) nanospheres and loading Rifampicin, one of the most potent and least …


Carbon Dioxide Enhanced Oil Recovery From The Citronelle Oil Field And Carbon Sequestration In The Donovan Sand, Southwest Alabama, Konstantinos A. Theodorou Jan 2013

Carbon Dioxide Enhanced Oil Recovery From The Citronelle Oil Field And Carbon Sequestration In The Donovan Sand, Southwest Alabama, Konstantinos A. Theodorou

All ETDs from UAB

Capturing carbon dioxide (CO2) from stationary sources and injecting it into deep underground geologic formations has been identified as a viable method for reducing carbon emissions to the atmosphere. Sedimentary rocks, such as sandstones overlain by shales or evaporites, are the preferred formations because their morphology and structure provide pore space, and containment for the long term storage of CO2. Sandstone formations have also served as repositories to migrating hydrocarbons, and are the sites of many oil recovery operations. For many depleted oil reservoirs, secondary waterflooding recovery methods are no longer efficient or economically viable, hence the application of tertiary …


A Generalized Noisy Communication Channel Approach For Quantum Computing, Fan Xiong Jan 2013

A Generalized Noisy Communication Channel Approach For Quantum Computing, Fan Xiong

All ETDs from UAB

Quantum computing is considered to be a promising technology for some specific types of computing purposes. Modeling of quantum computing could help study and research of this field. In this dissertation, we approach quantum computing from a communication perspective that is to model quantum computing with a generalized noisy communication channel approach. We proposed a generalized noisy communication channel approach (GNCom) for quantum computing. The proposed GNCom approach is applied to quantum computing as a universal quantum register. GNCom further extended the noisy communication channel framework by associating it with Quantum Electrodynamics (QED). Based on GNCom and QED, we proposed …


Characterization Of Macromolecular Structure Of Pyrolysis Products From A Colorado Green River Oil Shale, James L. Hillier, Thomas H. Fletcher, Mark S. Solum, Ronald J. Pugmire Jan 2013

Characterization Of Macromolecular Structure Of Pyrolysis Products From A Colorado Green River Oil Shale, James L. Hillier, Thomas H. Fletcher, Mark S. Solum, Ronald J. Pugmire

Faculty Publications

Volatile products from an oil shale from the Colorado Green River formation were studied by several methods. The oil shale was demineralized, and the resulting kerogen was also chemically analyzed. Both the oil shale and the demineralized kerogen were pyrolyzed at 10 K/min, and the pyrolysis products (light gas, tar, and char) were analyzed using 13C NMR, XPS, GC/MS, and FTIR. Low temperature ashing was performed in order to compare pyrolysis yields of oil shale and demineralized kerogen on a dry ash-free basis. Volatile yields of approximately 75% were achieved in an oil shale retort and 79% in the kerogen …


Prediction Of Sawdust Pyrolysis Yields From A Flat-Flame Burner Using The Cpd Model, Aaron D. Lewis, Thomas H. Fletcher Jan 2013

Prediction Of Sawdust Pyrolysis Yields From A Flat-Flame Burner Using The Cpd Model, Aaron D. Lewis, Thomas H. Fletcher

Faculty Publications

High heating rate pyrolysis experiments were performed on a softwood sawdust in a flat-flame burner reactor at temperatures from 1163 to 1433 K with particle residence times ranging from 23 to 102 ms at atmospheric pressure. Volatile yields of the 45−75 μm sawdust were measured and are believed to be similar to those that would occur in an industrial entrained-flow combustor or gasifier. A refractory tar yield near 1.5 wt % (dry, ash-free) was measured. A high percentage of the fully pyrolyzed sawdust char was spherical, having lost the original sawdust structure. It is suggested that the morphology of sawdust …


Embedding Librarians Into The Stem Publication Process, Anne E. Rauh, Linda M. Galloway Jan 2013

Embedding Librarians Into The Stem Publication Process, Anne E. Rauh, Linda M. Galloway

Librarian Publications

STEM Librarians at Syracuse University actively participate throughout the scientific publication process. This chapter will outline points in the process where librarian involvement is applicable and beneficial. Librarians Anne Rauh and Linda Galloway will explain how and why it is important to teach tools that organize scientific literature to faculty and students before they begin the writing process. The use of assessment techniques to help inform targeted publication venues will be described. Post-publication, this chapter will describe how to help authors gauge the impact of their work, promote their publications and increase their visibility.


Characterization And Aerosol Dispersion Performance Of Spray-Dried Chemotherapeutic Pegylated Phospholipid Particles For Dry Powder Inhalation Delivery In Lung Cancer, Samantha A. Meenach, Kimberly W. Anderson, J. Zach Hilt, Ronald J. Mcgarry, Heidi M. Mansour Jan 2013

Characterization And Aerosol Dispersion Performance Of Spray-Dried Chemotherapeutic Pegylated Phospholipid Particles For Dry Powder Inhalation Delivery In Lung Cancer, Samantha A. Meenach, Kimberly W. Anderson, J. Zach Hilt, Ronald J. Mcgarry, Heidi M. Mansour

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Pulmonary inhalation chemotherapeutic drug delivery offers many advantages for lung cancer patients in comparison to conventional systemic chemotherapy. Inhalable particles are advantageous in their ability to deliver drug deep in the lung by utilizing optimally sized particles and higher local drug dose delivery. In this work, spray-dried and co-spray dried inhalable lung surfactant-mimic PEGylated lipopolymers as microparticulate/nanoparticulate dry powders containing paclitaxel were rationally designed via organic solution advanced spray drying (no water) in closed-mode from dilute concentration feed solution. Dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine poly(ethylene glycol) (DPPE-PEG) with varying PEG chain length were mixed with varying amounts of paclitaxel in methanol …


Final Report: Multipath Modeling And Mitigation Using Multiple Antennas (M4a), Michael Rice Jan 2013

Final Report: Multipath Modeling And Mitigation Using Multiple Antennas (M4a), Michael Rice

Faculty Publications

This report documents the effort under contract W900KK-09-C-0016. The contract comprised four phases spanning 15 April 2009 to 1 December 2012. The relationship between the effort associated with each phase and the contents of this report are as follows: Phase 1 was devoted exclusively to the channel sounding experiments with the UH-1H helicopter. The experimental setup, procedure, and results for the channel sounding experiments at Cairns Army Airfield and Patuxent River are described in Chapter 2. Good, usable data at upper L-band was captured during the Cairns Army Airfield experiments. Phase 2 was devoted to the channel sounding experiments with …


Exploring Current And Projected Skills And Knowledge Areas To Meet U.S. Commercial Space Industry Needs, Sonya A. H. Mcmullen, Mac J. Mcmullen, Kenneth Witcher Jan 2013

Exploring Current And Projected Skills And Knowledge Areas To Meet U.S. Commercial Space Industry Needs, Sonya A. H. Mcmullen, Mac J. Mcmullen, Kenneth Witcher

Publications

In 2007, the Committee on Meeting the Workforce Needs for the National Vision for Space Exploration published findings related to age and skills of the current National Aeronautics and Space Administration (NASA) workforce and projected potential expertise shortages as a result of retirement in the 2014-2015 time frame. In addition, the expanding commercial space industry in both the United States and Europe will likely create further demand for space experts in engineering and a variety of related fields. Although NASA contributes $162 million in funding for education programs annually, those programs target kindergarten through grade 12, not collegiate-level programs. Further, …


Improving Brain–Machine Interface Performance By Decoding Intended Future Movements, Francis R. Willett, Aaron J. Suminski, Andrew H. Fagg, Nicholas G. Hatsopoulos Jan 2013

Improving Brain–Machine Interface Performance By Decoding Intended Future Movements, Francis R. Willett, Aaron J. Suminski, Andrew H. Fagg, Nicholas G. Hatsopoulos

Biomedical Engineering Faculty Research and Publications

Objective. A brain–machine interface (BMI) records neural signals in real time from a subject's brain, interprets them as motor commands, and reroutes them to a device such as a robotic arm, so as to restore lost motor function. Our objective here is to improve BMI performance by minimizing the deleterious effects of delay in the BMI control loop. We mitigate the effects of delay by decoding the subject's intended movements a short time lead in the future. Approach. We use the decoded, intended future movements of the subject as the control signal that drives the movement of our BMI. This …


Sand Penetration: A Near Nose Investigation Of A Sand Penetration Event, Andrew Van Vooren, John Borg, Joshua Felts Jan 2013

Sand Penetration: A Near Nose Investigation Of A Sand Penetration Event, Andrew Van Vooren, John Borg, Joshua Felts

Mechanical Engineering Faculty Research and Publications

This paper presents experimental and computational results of a long-rod penetrating dry granular sand at velocities near 100 m/s. The objective of this work is to develop a fundamental understanding of the formation and transmission of dynamic force chains, and the motion and fracture of the individual sand grains as the projectile passes. This is accomplished by launching a projectile along a view window, backed by sand, in order to directly view and photograph the projectile/sand interactions. Within the sand system, a two-wave structure was observed, composed of a compaction wave (bow shock) that detaches from the dart and moves …


Modeling The Structural-Thermal-Electrical Coupling In An Electrostatically Actuated Mems Switch And Its Impact On The Switch Stability, Hassen M. Ouakad, Mohammad I. Younis Jan 2013

Modeling The Structural-Thermal-Electrical Coupling In An Electrostatically Actuated Mems Switch And Its Impact On The Switch Stability, Hassen M. Ouakad, Mohammad I. Younis

Mechanical Engineering Faculty Scholarship

Modeling and analysis for the static behavior and collapse instabilities of a MEMS cantilever switch subjected to both electrical and thermal loadings are presented. The thermal loading forces can be as a result of a huge amount of switching contact of the microswitch. The model considers the microbeam as a continuous medium and the electric force as a nonlinear function of displacement and accounts for its fringing-field effect. The electric force is assumed to be distributed over specific lengths underneath the microbeam. A boundary-value solver is used to study the collapse instability, which brings the microbeam from its unstuck configuration …


Iterative Unbiased Fir State Estimation: A Review Of Algorithms, Yuriy S. Shmaliy, Daniel J. Simon Jan 2013

Iterative Unbiased Fir State Estimation: A Review Of Algorithms, Yuriy S. Shmaliy, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

In this paper, we develop in part and review various iterative unbiased finite impulse response (UFIR) algorithms (both direct and two-stage) for the filtering, smoothing, and prediction of time-varying and time-invariant discrete state-space models in white Gaussian noise environments. The distinctive property of UFIR algorithms is that noise statistics are completely ignored. Instead, an optimal window size is required for optimal performance. We show that the optimal window size can be determined via measurements with no reference. UFIR algorithms are computationally more demanding than Kalman filters, but this extra computational effort can be alleviated with parallel computing, and the extra …


Biogeography-Based Optimization For Hydraulic Prosthetic Knee Control, Tim Wilmot, George Thomas, Berney Montavon, Rick Rarick, Antonie J. Van Den Bogert, Steve Szatmary, Daniel J. Simon, William Smith, Sergey Samorezov Jan 2013

Biogeography-Based Optimization For Hydraulic Prosthetic Knee Control, Tim Wilmot, George Thomas, Berney Montavon, Rick Rarick, Antonie J. Van Den Bogert, Steve Szatmary, Daniel J. Simon, William Smith, Sergey Samorezov

Electrical and Computer Engineering Faculty Publications

We discuss open-loop control development and simulation results for a newly-developed cyber-physical system (CPS) used as a semi-active, above-knee prosthesis. The control signal of our CPS consists of two hydraulic valve settings that control a linear cylinder actuator and provide torque to the prosthetic knee. We develop open-loop control using biogeography-based optimization (BBO), which is a recently developed evolutionary algorithm. The research contributes to the field of cyber-physical systems by showing that it is possible to find effective open-loop control signals for our newly proposed semi-active hydraulic knee prosthesis through a dual-system optimization process which includes both human and robot …


Byzantine Fault Tolerance For Session-Oriented Multi-Tiered Applications, Hua Chai, Wenbing Zhao Jan 2013

Byzantine Fault Tolerance For Session-Oriented Multi-Tiered Applications, Hua Chai, Wenbing Zhao

Electrical and Computer Engineering Faculty Publications

This article presents a lightweight Byzantine fault tolerance (BFT) framework for session-oriented multi-tiered applications. We conclude that it is sufficient to use a lightweight BFT algorithm instead of a traditional BFT algorithm, based on a comprehensive study of the threat model to, and the state model of, the session-oriented multi-tiered applications. The lightweight BFT algorithm uses source ordering, rather than total ordering, of incoming requests to achieve Byzantine fault tolerant state-machine replication of such type of applications. The performance of the lightweight BFT framework is evaluated using a shopping cart application prototype built on the web services platform. The same …


Detection Of Prostate Specific Antigen In Serum At The Femto-Gram Per Milliliter Level Using The Intrinsic Amplification Of A Field-Effect Enzymatic Immuno-Sensing System, Jiapeng Wang, Siu-Tung Yau Jan 2013

Detection Of Prostate Specific Antigen In Serum At The Femto-Gram Per Milliliter Level Using The Intrinsic Amplification Of A Field-Effect Enzymatic Immuno-Sensing System, Jiapeng Wang, Siu-Tung Yau

Electrical and Computer Engineering Faculty Publications

Ultrasensitive detection of prostate specific antigen (PSA) has been achieved by applying the field-effectenzymatic detection (FEED) technique to the sandwich immuno-sensing technique. The voltage-controlled intrinsic amplification provided by FEED enabled the detection of PSA contained in serumon the femto-gram/mL level. Two electrochemical approaches used to obtain the amperometric detec-tion signal resulted in similar detection limits and sensitivities. The lowest PSA detection limit achievedwas 27 fg mL-1. The high selectivity of the detection system was reflected in the fact that PSA detectionwas successful on the fg mL-1level, where biological substances other than PSA had a 1-million-foldhigher concentration. Electron transfer through the …


Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu-Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wanga Jan 2013

Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu-Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wanga

Electrical and Computer Engineering Faculty Publications

The field-effect enzymatic detection (FEED) technique was used to control the kinetics of the enzymatic conversion of glucose to gluconolactone. The glucose–gluconolactone conversion occurring at an enzyme-immobilized electrode, a well-studied process, was confirmed using mass spectrometry. Electrochemical studies showed that the glucose oxidation current depends on the gating voltage VG and the ion concentration of the sample solution. Additionally, the depletion of glucose in the sample also showed a dependence on VG. FEED was used to detect H2O2 on the zepto-molar level in order to show the ultrasensitive detection capability of the technique. These results, while providing evidence for the …


Complex System Optimization Using Biogeography-Based Optimization, Dawei Du, Dan Simon Jan 2013

Complex System Optimization Using Biogeography-Based Optimization, Dawei Du, Dan Simon

Electrical and Computer Engineering Faculty Publications

Complex systems are frequently found in modern industry. But with their multisubsystems, multiobjectives, and multiconstraints, the optimization of complex systems is extremely hard. In this paper, a new algorithm adapted from biogeography-based optimization (BBO) is introduced for complex system optimization. BBO/Complex is the combination of BBO with a multiobjective ranking system, an innovative migration approach, and effective diversity control. Based on comparisons with three complex system optimization algorithms (multidisciplinary feasible (MDF), individual discipline feasible (IDF), and collaborative optimization (CO)) on four real-world benchmark problems, BBO/Complex demonstrates competitive performance. BBO/Complex provides the best performance in three of the benchmark problems and …


Absorptive And Refractive Optical Nonlinearities In Organic Molecules And Semiconductors, Davorin Peceli Jan 2013

Absorptive And Refractive Optical Nonlinearities In Organic Molecules And Semiconductors, Davorin Peceli

Electronic Theses and Dissertations

The main purpose of this dissertation to investigate photophysical properties, third order nonlinearity and free carrier absorption and refraction in organic materials and semiconductors. Special emphasis of this dissertation is on characterization techniques of molecules with enhanced intersystem crossing rate and study of different approaches of increasing triplet quantum yield in organic molecules. Both linear and nonlinear characterization methods are described. Linear spectroscopic characterization includes absorption, fluorescence, quantum yield, anisotropy, and singletoxygen generation measurements. Nonlinear characterization, performed by picosecond and femtosecond laser systems (single and double pump-probe and Z-scan measurements), includes measurements of the triplet quantum yields, excited-state absorption, two-photon …


Non-Degenerate Two Photon Gain In Bulk Gallium Arsenide, Brendan Turnbull Jan 2013

Non-Degenerate Two Photon Gain In Bulk Gallium Arsenide, Brendan Turnbull

Electronic Theses and Dissertations

The purpose of this thesis is to investigate the nonlinear phenomena known as doubly-stimulated, non-degenerate two-photon emission (ND-2PE) in Gallium Arsenide (GaAs). 2PE refers to the simultaneous emission of two-photons as electrons move from the conduction band in a direct gap semiconductor to the valence band. Following the same path for describing one-photon emission (1PE) we describe 2PE as a product of the irradiance, and the negative of the loss which in this case is two-photon absorption, , the negative coming from the population inversion. We attempt to observe 2PE by using a frequency non-degenerate pump-probe experiment in which a …


Properties Of High Energy Laser Light Transmission Through Large Core Optical Cables, Christopher Kennedy Jan 2013

Properties Of High Energy Laser Light Transmission Through Large Core Optical Cables, Christopher Kennedy

Electronic Theses and Dissertations

Laser induced damage is of interest in studying the transmission of large amounts of optical energy through step-index, large core multimode fibers. Optical fibers often have to be routed around objects when laser light is being transmitted between two locations which require the fiber to bend into a curve. Depending on how tight the bend is, this can result in transmission losses or even catastrophic damage when the energy density of the laser pulse exceeds the damage threshold of silica glass. The purpose of this study is to: Establish a minimum bend radius that would allow high energy (GW/cm2 ) …


Beam Deflection, Matthias Münnich, Jan 2013

Beam Deflection, Matthias Münnich,

Electronic Theses and Dissertations

In order to fully understand the third order nonlinear optical response of materials under high irradiance excitation it is necessary to study the temporal and polarization dependence of nonlinear refraction and absorption. There are several existing approaches such as Z-scan and pump-probe techniques to determine those responses. As part of this work, these approaches will be briefly outlined before presenting beam deflection, applied from photothermal beam deflection, as an alternative experimental technique to determine the nonlinear refraction with its temporal and polarization dynamics. This technique measures the angle of the probe beam deflected via the index gradient of the material …


Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox Jan 2013

Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox

Undergraduate Honors Capstone Projects

Team Hot Stuff designed a thermal capacitor for Senior Design I at Utah State University. This thermal capacitor is intended for use in the food service industry as a low-cost alternative to chafers. Chafers are platters which use oil burners to keep food warm. The client for this thermal capacitor is Thermal Management Technologies (TMT), a company specializing in thermal science solutions whose mission is “to provide simple, practical thermal science solutions to a wide range of platforms including: Industry, Defense, and Space”1. The founder and president of TMT, Dr. J. Clair Batty, serves as a mentor for …


Evolution Of Multispectral Aerosol Optical Properties In A Biogenically-Influenced Urban Environment During The Cares Campaign, Madhu Gyawali, W. Patrick Arnott, Rahul A. Zaveri, C. Song, Mikhail Pekour, B. Flowers, Manvendra K. Dubey, Ari Setyan, Qi Zhang, Joseph Harworth, James Gregory Radney, Dean B. Atkinson, S. China, Claudio Mazzoleni, Kyle Gorkowski, R. Subramanian, B. Tom Jobson, Hans Moosmüller Jan 2013

Evolution Of Multispectral Aerosol Optical Properties In A Biogenically-Influenced Urban Environment During The Cares Campaign, Madhu Gyawali, W. Patrick Arnott, Rahul A. Zaveri, C. Song, Mikhail Pekour, B. Flowers, Manvendra K. Dubey, Ari Setyan, Qi Zhang, Joseph Harworth, James Gregory Radney, Dean B. Atkinson, S. China, Claudio Mazzoleni, Kyle Gorkowski, R. Subramanian, B. Tom Jobson, Hans Moosmüller

Chemistry Faculty Publications and Presentations

Ground-based aerosol measurements made in June 2010 within Sacramento urban area (site T0) and at a 40-km downwind location (site T1) in the forested Sierra Nevada foothills area are used to investigate the evolution of multispectral optical properties as the urban aerosols aged and interacted with biogenic emissions. Along with black carbon and non-refractory aerosol mass and composition observations, spectral absorption (ᵝabs), scattering (ᵝsca), and extinction (ᵝext) coefficients for wavelengths ranging from 355 to 1064nm were measured at both sites using photoacoustic (PA) instruments with integrating nephelometers and using cavity ring-down (CRD) instruments. The …


Wavelength Scale Resonant Structures For Integrated Photonic Applications, Matthew Weed Jan 2013

Wavelength Scale Resonant Structures For Integrated Photonic Applications, Matthew Weed

Electronic Theses and Dissertations

An approach to integrated frequency-comb filtering is presented, building from a background in photonic crystal cavity design and fabrication. Previous work in the development of quantum information processing devices through integrated photonic crystals consists of photonic band gap engineering and methods of on-chip photon transfer. This work leads directly to research into coupled-resonator optical waveguides which stands as a basis for the primary line of investigation. These coupled cavity systems offer the designer slow light propagation which increases photon lifetime, reduces size limitations toward on-chip integration, and offers enhanced light-matter interaction. A unique resonant structure explained by various numerical models …


The Impact Of Growth Conditions On Cubic Znmgo Ultraviolet Sensors, Ryan Boutwell Jan 2013

The Impact Of Growth Conditions On Cubic Znmgo Ultraviolet Sensors, Ryan Boutwell

Electronic Theses and Dissertations

Cubic Zn1-xMgxO (c-Zn1-xMgxO) thin films have opened the deep ultraviolet (DUV) spectrum to exploration by oxide optoelectronic devices. These extraordinary films are readily wet-etch-able, have inversion symmetric lattices, and are made of common and safe constituents. They also host a number of new exciting experimental and theoretical challenges. Here, the relation between growth conditions of the c-Zn1-xMgxO film and performance of fabricated ultraviolet (UV) sensors is investigated. Plasma-Enhanced Molecular Beam Epitaxy was used to grow Zn1-xMgxO thin films and formation conditions were explored by varying the growth temperature, Mg source flux, oxygen flow rate, and radio-frequency (RF) power coupled into …