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Synchrotron Based Infrared Microspectroscopy Of Carbonaceous Chondrites., Mehmet Yesiltas
Synchrotron Based Infrared Microspectroscopy Of Carbonaceous Chondrites., Mehmet Yesiltas
Electronic Theses and Dissertations
Relationships between organic molecules and inorganic minerals are investigated in five carbonaceous chondrites, Northwest Africa 852 (CR2), Tagish Lake (C2-ungroupped), Orgueil (CI1), Sutter's Mill (CM), and Murchison (CM2), with micron spatial resolution using synchrotron-based imaging micro-FTIR spectroscopy. Correlations based on absorption strength for various constituents are determined using statistical correlation analysis. Silicate band is found to be positively correlated with stretching modes of aliphatic hydrocarbons in NWA 852 and Tagish Lake. The former is highly correlated with the hydration band in all meteorites. Negative correlation is observed between water+organics and carbonate bands in all meteorites. Two dimensional infrared maps for …
Low Absorption Liquid Crystal Materials For Midwave Infrared, Amy Creekmore
Low Absorption Liquid Crystal Materials For Midwave Infrared, Amy Creekmore
Electronic Theses and Dissertations
Liquid crystal is an amazing class of soft matters with applications spanning from visible, infrared, millimeter wave, to terahertz. In addition to direct-view displays and projection displays, liquid crystal is also widely used in adaptive optics, tunable-focus lens, and laser beam steering. Although the visible region has well developed materials and mixtures for the vast variety of applications, the midwave infrared (MWIR) region of the electromagnetic spectrum invites much development as only a few materials have been developed with these applications in mind. Unlike visible region, the major challenge for mid-wave infrared liquid crystal is inherently large absorption loss. To …
Opportunistic Spectrum Utilization By Cognitive Radio Networks: Challenges And Solutions, Muhammad Faisal Amjad
Opportunistic Spectrum Utilization By Cognitive Radio Networks: Challenges And Solutions, Muhammad Faisal Amjad
Electronic Theses and Dissertations
Cognitive Radio Network (CRN) is an emerging paradigm that makes use of Dynamic Spectrum Access (DSA) to communicate opportunistically, in the un-licensed Industrial, Scientific and Medical bands or frequency bands otherwise licensed to incumbent users such as TV broadcast. Interest in the development of CRNs is because of severe under-utilization of spectrum bands by the incumbent Primary Users (PUs) that have the license to use them coupled with an ever-increasing demand for unlicensed spectrum for a variety of new mobile and wireless applications. The essence of Cognitive Radio (CR) operation is the cooperative and opportunistic utilization of licensed spectrum bands …
Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti
Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti
Electronic Theses and Dissertations
Studying and simulating social systems including human groups and societies can be a complex problem. In order to build a model that simulates humans' actions, it is necessary to consider the major factors that affect human behavior. Norms are one of these factors: social norms are the customary rules that govern behavior in groups and societies. Norms are everywhere around us, from the way people handshake or bow to the clothes they wear. They play a large role in determining our behaviors. Studies on norms are much older than the age of computer science, since normative studies have been a …
Reasoning Tradeoffs In Implicit Invocation And Aspect Oriented Languages, Jose Sanchez Salazar
Reasoning Tradeoffs In Implicit Invocation And Aspect Oriented Languages, Jose Sanchez Salazar
Electronic Theses and Dissertations
To reason about a program means to state or conclude, by logical means, some properties the program exhibits; like its correctness according to certain expected behavior. The continuous need for more ambitious, more complex, and more dependable software systems demands for better mechanisms to modularize them and reason about their correctness. The reasoning process is affected by the design decisions made by the developer of the program and by the features supported by the programming language used. Beyond Object Orientation, Implicit Invocation and Aspect Oriented languages pose very hard reasoning challenges. Important tradeoffs must be considered while reasoning about a …
Mass Spectral Studies To Investigate Butylbenzene Fragmentation Pathway And Pyrolysis Products., Balasubramaniam Lingam
Mass Spectral Studies To Investigate Butylbenzene Fragmentation Pathway And Pyrolysis Products., Balasubramaniam Lingam
Electronic Theses and Dissertations
In this dissertation research, two fundamental studies involving gas chromatography mass spectrometry of n-butylbenzene and pyrolysis products are presented. In the first study, fragmentation pathways of n-butylbenzene in quadrupole ion trap have been investigated. At low energy, product ion corresponding to m/z 92 and m/z 91 are formed via competitive parallel dissociation. Studies have also shown that at higher energy m/z 92 has sufficient internal energy to undergo further fragmentation yielding m/z 91 via consecutive dissociation. Thus in order to discern the fragmentation pathways of n-butylbenzene, the technique of two-dimensional correlation spectroscopy (2DCOS) was applied to the mass spectral data. …
Observations, Thermochemical Calculations, And Modeling Of Exoplanetary Atmospheres, Jasmina Blecic
Observations, Thermochemical Calculations, And Modeling Of Exoplanetary Atmospheres, Jasmina Blecic
Electronic Theses and Dissertations
This dissertation as a whole aims to provide the means to better understand hot-Jupiter planets through observing, performing thermochemical calculations, and modeling their atmospheres. We used Spitzer multi-wavelength secondary-eclipse observations to characterize planetary atmospheres. We chose targets with high signal-to-noise ratios, as their deep eclipses allow us to detect signatures of spectral features and assess planetary atmospheric structure and composition with greater certainty. Chapter 1 gives a short introduction. Chapter 2 presents the Spitzer secondary-eclipse analysis and atmospheric characterization of WASP-14b. The decrease in flux when a planet passes behind its host star reveals the planet dayside thermal emission, which, …
Selective Electro-Magnetic Absorbers Based On Metal-Dielectric-Metal Thin-Film Cavities, Janardan Nath
Selective Electro-Magnetic Absorbers Based On Metal-Dielectric-Metal Thin-Film Cavities, Janardan Nath
Electronic Theses and Dissertations
Efficient absorption of light is required for a large number of applications such as thermo-photovoltaics,thermal imaging, bio-sensing, thermal emitters, astronomy, and stealth technology. Strong light absorbers found in nature with high intrinsic losses such as carbon black, metal-black, and carbon nano-tubes etc. are bulky, not design-tunable and are hard to pattern for micro- and nano- devices. We developed thin-film, high performance absorbers in the visible, near-, mid-, long-wave - and far-IR region based on a 3 layer metal-dielectric-metal (MDM) structure. We fabricated a 3-layerMDMabsorber with large band-widths in the visible and near IR spectral range without any lithographic patterning. This …
Characterizing Exoplanet Atmospheres: From Light-Curve Observations To Radiative-Transfer Modeling, Patricio Cubillos Vallejos
Characterizing Exoplanet Atmospheres: From Light-Curve Observations To Radiative-Transfer Modeling, Patricio Cubillos Vallejos
Electronic Theses and Dissertations
Multi-wavelength transit and secondary-eclipse light-curve observations are some of the most powerful techniques to probe the thermo-chemical properties of exoplanets. Although the large planet-to-star brightness contrast and few available spectral bands produce data with low signal-to-noise ratios, a Bayesian approach can robustly reveal what constraints we can set, without over-interpreting the data. Here I performed an end-to-end analysis of transiting exoplanet data. I analyzed space-telescope data for three planets to characterize their atmospheres and refine their orbits, investigated correlated noise estimators, and contributed to the development of the respective data-analysis pipelines. Chapters 2 and 3 describe the Photometry for Orbits, …
Folate Conjugated Hyperbranched Polyester Nanoparticles For Prostate Tumor-Targeted Delivery Of A Cytotoxic Peptide Via Prostate Specific Membrane Antigen, Orielyz Flores-Fernandez
Folate Conjugated Hyperbranched Polyester Nanoparticles For Prostate Tumor-Targeted Delivery Of A Cytotoxic Peptide Via Prostate Specific Membrane Antigen, Orielyz Flores-Fernandez
Electronic Theses and Dissertations
Prostate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the nanocarrier to improve the selectivity of the nanoparticle towards specific cell surface targets in prostate cancer cell lines. Specifically we evaluated LNCaP that up-regulated the PSMA receptor. …
Resource Management In Large-Scale Systems, Ashkan Paya
Resource Management In Large-Scale Systems, Ashkan Paya
Electronic Theses and Dissertations
The focus of this thesis is resource management in large-scale systems. Our primary concerns are energy management and practical principles for self-organization and self-management. The main contributions of our work are: 1. Models. We proposed several models for different aspects of resource management, e.g., energy-aware load balancing and application scaling for the cloud ecosystem, hierarchical architecture model for self-organizing and self-manageable systems and a new cloud delivery model based on auction-driven self-organization approach. 2. Algorithms. We also proposed several different algorithms for the models described above. Algorithms such as coalition formation, combinatorial auctions and clustering algorithm for scale-free organizations of …
An Integrated Framework For Automated Data Collection And Processing For Discrete Event Simulation Models, Carlos Rodriguez
An Integrated Framework For Automated Data Collection And Processing For Discrete Event Simulation Models, Carlos Rodriguez
Electronic Theses and Dissertations
Discrete Events Simulation (DES) is a powerful tool of modeling and analysis used in different disciplines. DES models require data in order to determine the different parameters that drive the simulations. The literature about DES input data management indicates that the preparation of necessary input data is often a highly manual process, which causes inefficiencies, significant time consumption and a negative user experience. The focus of this research investigation is addressing the manual data collection and processing (MDCAP) problem prevalent in DES projects. This research investigation presents an integrated framework to solve the MDCAP problem by classifying the data needed …
Parallel Fabrication And Transport Properties Of Carbon Nanotube Single Electron Transistors, Muhammad Islam
Parallel Fabrication And Transport Properties Of Carbon Nanotube Single Electron Transistors, Muhammad Islam
Electronic Theses and Dissertations
Single electron transistors (SET) have attracted significant attention as a potential building block for post CMOS nanoelectronic devices. However, lack of reproducible and parallel fabrication approach and room temperature operation are the two major bottlenecks for practical realization of SET based devices. In this thesis, I demonstrate large scale single electron transistors fabrication techniques using solution processed single wall carbon nanotubes (SWNTs) and studied their electron transport properties. The approach is based on the assembly of individual SWNTs via dielectrophoresis (DEP) at the selected position of the circuit and formation of tunnel barriers on SWNT. Two different techniques: i) metal-SWNT …
Convective Heat Transfer In Quasi-One-Dimensional Magnetic Fluid In Horizontal Field And Temperature Gradients, Jun Huang
Electronic Theses and Dissertations
In this work we studied the convective heat transfer in a magnetic fluid in both zero and applied magnetic fields. The natural convection is observed in a quasi-one dimensional magnetic fluid in a horizontal temperature gradient. The horizontal non-homogeneous magnetic fields were applied across the sample cell either parallel or anti-parallel to the temperature gradient. The temperature profile was measured by eight thermocouples and temperature sensitive paint. The flow velocity field and streamlines were obtained by optical flow method. Calculated Nusselt numbers, Rayleigh number, and Grashof number show that the convective flow is the main heat transfer mechanism in applied …
Structure-Property Relationship Of The Two-Photon Circular Dichroism Of Compounds With Axial And Helical Chirality, Carlos Diaz
Structure-Property Relationship Of The Two-Photon Circular Dichroism Of Compounds With Axial And Helical Chirality, Carlos Diaz
Electronic Theses and Dissertations
Back in 1894 Lord Kelvin coined the term "chiral" in order to refer to molecules whose mirror images were not superimposable with themselves. Over the years, research has demonstrated the important role that chiral molecules play in life, chemistry, and biology as well as their importance in the development of new drugs and technologies. The efforts to understand chiral systems have been mainly driven by spectroscopic methods that leverage on the opposite responses that enantiomers have to linear or circularly polarized light of both handedness. More specifically, Electronic Circular Dichroism (ECD) which measures the differences in linear absorption of left …
Exploring 3d User Interface Technologies For Improving The Gaming Experience, Arun Kulshreshth
Exploring 3d User Interface Technologies For Improving The Gaming Experience, Arun Kulshreshth
Electronic Theses and Dissertations
3D user interface technologies have the potential to make games more immersive & engaging and thus potentially provide a better user experience to gamers. Although 3D user interface technologies are available for games, it is still unclear how their usage affects game play and if there are any user performance benefits. A systematic study of these technologies in game environments is required to understand how game play is affected and how we can optimize the usage in order to achieve better game play experience. This dissertation seeks to improve the gaming experience by exploring several 3DUI technologies. In this work, …
True Linearized Intensity Modulation For Photonic Analog To Digital Conversion Using An Injection-Locked Mode-Locked Laser, Edris Sarailou
True Linearized Intensity Modulation For Photonic Analog To Digital Conversion Using An Injection-Locked Mode-Locked Laser, Edris Sarailou
Electronic Theses and Dissertations
A true linearized interferometric intensity modulator for pulsed light has been proposed and experimentally presented in this thesis. This has been achieved by introducing a mode-locked laser into one of the arms of a Mach-Zehnder interferometer and injection-locking it to the input light (which is pulsed and periodic). By modulating the injection-locked laser, and combining its output light with the light from the other arm of interferometer in quadrature, one can achieve true linearized intensity modulator. This linearity comes from the arcsine phase response of the injection-locked mode-locked laser (as suggested by steady-state solution of Adler's equation) when it is …
Electronic Transport Properties Of Carbon Nanotubes: The Impact Of Atomic Charged Impurities, Ryuichi Tsuchikawa
Electronic Transport Properties Of Carbon Nanotubes: The Impact Of Atomic Charged Impurities, Ryuichi Tsuchikawa
Electronic Theses and Dissertations
Even changing one atom in nanoscale materials is expected to alter their properties due to their small physical sizes. Such sensitivity can be utilized to modify materials' properties from bottom up and is essential for the utility of nanoscale materials. As such, the impact of extrinsic atomic adsorbates was measured on pristine graphene and a network of carbon nanotubes using atomic hydrogen, cesium atoms, and dye molecules. In order to further quantify such an atomic influence, the resistance induced by a single potassium atom on metallic and semiconducting carbon nanotubes was measured for the first time. Carbon nanotubes are sensitive …
Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell
Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell
Electronic Theses and Dissertations
Mobile device data continues to increase in significance in both civil and criminal investigations. Location data is often of particular interest. To date, research has established that the devices are location aware, incorporate a variety of resources to obtain location information, and cache the information in various ways. However, a review of the existing research suggests varying degrees of reliability of any such recovered location data. In an effort to clarify the issue, this project offers case studies of multiple Android mobile devices utilized in controlled conditions with known settings and applications in documented locations. The study uses data recovered …
The Design, Implementation, And Refinement Of Wait-Free Algorithms And Containers, Steven Feldman
The Design, Implementation, And Refinement Of Wait-Free Algorithms And Containers, Steven Feldman
Electronic Theses and Dissertations
My research has been on the development of concurrent algorithms for shared memory systems that provide guarantees of progress. Research into such algorithms is important to developers implementing applications on mission critical and time sensitive systems. These guarantees of progress provide safety properties and freedom from many hazards, such as dead-lock, live-lock, and thread starvation. In addition to the safety concerns, the fine-grained synchronization used in implementing these algorithms promises to provide scalable performance in massively parallel systems. My research has resulted in the development of wait-free versions of the stack, hash map, ring buffer, vector, and a multi-word compare-and-swap …
Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith
Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith
Electronic Theses and Dissertations
High sensitivity uncooled microbolometers are necessary to meet the needs of the next generation of infrared detectors, which seek low power consumption and production cost without sacrificing performance. Presented here is the design, fabrication, and characterization of a microbolometer with responsivity enhanced by novel highly absorptive coatings. The device utilizes a gold-doped vanadium oxide film in a standard air bridge design. Performance estimations are calculated from current theory, and efforts to maximize signal to noise ratio are shown and evaluated. Most notably, presented are the experimental results and analysis from the integration of two different absorptive coatings: a patterned gold …
Density-Functional Theory+Dynamical Mean-Field Theory Study Of The Magnetic Properties Of Transition-Metal Nanostructures, Alamgir Kabir
Density-Functional Theory+Dynamical Mean-Field Theory Study Of The Magnetic Properties Of Transition-Metal Nanostructures, Alamgir Kabir
Electronic Theses and Dissertations
In this thesis, Density Functional Theory (DFT) and Dynamical Mean-Field Theory (DMFT) approaches are applied to study the magnetic properties of transition metal nanosystems of different sizes and compositions. In particular, in order to take into account dynamical electron correlation effects (time-resolved local charge interactions), we have adopted the DFT+DMFT formalism and made it suitable for application to nanostructures. Preliminary application of this DFT+DMFT approach, using available codes, to study the magnetic properties of small (2 to 5-atom) Fe and FePt clusters provide meaningful results: dynamical effects lead to a reduction of the cluster magnetic moment as compared to that …
Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim
Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim
Electronic Theses and Dissertations
Over the past several decades the phenomenon of luminescence (divided into fluorescence and phosphorescence) has received great attention in the field of biological science. This quest has motivated scientists for a variety of applications, including fluorescence imaging. Fluorescence microscopy techniques that provide unique advantages, such as high spatial resolution and superior sensitivity, have been regarded as attractive tools in biophotonics. With the progress of ultrafast laser sources, two-photon absorption (2PA), in which a molecule absorbs two photons simultaneously, has opened possibilities of using it for various applications. Two-photon fluorescence microscopy (2PFM), which affords deeper tissue penetration and excellent three-dimensional (3D) …
Transverse Mode Selection And Brightness Enhancement In Laser Resonators By Means Of Volume Bragg Gratings, Brian Anderson
Transverse Mode Selection And Brightness Enhancement In Laser Resonators By Means Of Volume Bragg Gratings, Brian Anderson
Electronic Theses and Dissertations
The design of high power lasers requires large mode areas to overcome various intensity driven nonlinear effects. Increasing the aperture size within the laser can overcome these effects, but typically result in multi-transverse mode output and reduced beam quality, limiting the brightness of the system. As one possible solution, the angular selectivity of a diffractive optical element is proposed as a spatial filter, allowing for the design of compact high brightness sources not possible with conventional methods of transverse mode selection. This thesis explores the angular selectivity of volume Bragg gratings (VBGs) and their use as spatial transverse mode filters …
Gauging Training Effectiveness Of Virtual Environment Simulation Based Applications For An Infantry Soldier Training Task, Douglas Maxwell
Gauging Training Effectiveness Of Virtual Environment Simulation Based Applications For An Infantry Soldier Training Task, Douglas Maxwell
Electronic Theses and Dissertations
The U.S. Army Training and Doctrine Command*s Army Learning Concept 2015 and Army Training Concept 2025 are documents that discuss the need for an adaptive soldier learning model with a flexible training delivery methodology. The U.S. Army has been investing in serious gaming technology for the past two decades as a cost effective means to teach tactics and strategy. Today, the U.S. Army is seeking to expand its application of virtual environment training to areas such as cultural awareness and human network analysis for the infantry soldier. These new expanded applications will require a higher level of non-determinant behavior inside …
Theoretical And Computational Studies Of The Electronic, Structural, Vibrational, And Thermodynamic Properties Of Transition Metal Nanoparticles, Ghazal Shafai Erfani
Theoretical And Computational Studies Of The Electronic, Structural, Vibrational, And Thermodynamic Properties Of Transition Metal Nanoparticles, Ghazal Shafai Erfani
Electronic Theses and Dissertations
The main objective of this dissertation is to provide better understanding of the atomic configurations, electronic structure, vibrational properties, and thermodynamics of transition metal nanoparticles and evaluate the intrinsic (i.e. size and shape) and extrinsic (i.e. ligands, adsorbates, and support) effects on the aforementioned properties through a simulational approach. The presented research provides insight into better understanding of the morphological changes of the nanoparticles that are brought about by the intrinsic factors as well as the extrinsic ones. The preference of certain ligands to stabilize specific sizes of nanoparticles is investigated. The intrinsic and extrinsic effects on the electronic structure …
Autonomous Quadcopter Videographer, Quiquia Rey Coaguila
Autonomous Quadcopter Videographer, Quiquia Rey Coaguila
Electronic Theses and Dissertations
In recent years, the interest in quadcopters as a robotics platform for autonomous photography has increased. This is due to their small size and mobility, which allow them to reach places that are difficult or even impossible for humans. This thesis focuses on the design of an autonomous quadcopter videographer, i.e. a quadcopter capable of capturing good footage of a specific subject. In order to obtain this footage, the system needs to choose appropriate vantage points and control the quadcopter. Skilled human videographers can easily spot good filming locations where the subject and its actions can be seen clearly in …
Modeling User Transportation Patterns Using Mobile Devices, Erfan Davami
Modeling User Transportation Patterns Using Mobile Devices, Erfan Davami
Electronic Theses and Dissertations
Participatory sensing frameworks use humans and their computing devices as a large mobile sensing network. Dramatic accessibility and affordability have turned mobile devices (smartphone and tablet computers) into the most popular computational machines in the world, exceeding laptops. By the end of 2013, more than 1.5 billion people on earth will have a smartphone. Increased coverage and higher speeds of cellular networks have given these devices the power to constantly stream large amounts of data. Most mobile devices are equipped with advanced sensors such as GPS, cameras, and microphones. This expansion of smartphone numbers and power has created a sensing …
Atmospheric Pressure Chemical Vapor Deposition Of Functional Oxide Materials For Crystalline Silicon Solar Cells, Kristopher Davis
Atmospheric Pressure Chemical Vapor Deposition Of Functional Oxide Materials For Crystalline Silicon Solar Cells, Kristopher Davis
Electronic Theses and Dissertations
Functional oxides are versatile materials that can simultaneously enable efficiency gains and cost reductions in crystalline silicon (c-Si) solar cells. In this work, the deposition of functional oxide materials using atmospheric pressure chemical vapor deposition (APCVD) and the integration of these materials into c-Si solar cells are explored. Specifically, thin oxide films and multi-layer film stacks are utilized for the following purposes: (1) to minimize front surface reflectance without increasing parasitic absorption within the anti-reflection coating(s); (2) to maximize internal back reflectance of rear passivated cells, thereby increasing optical absorption of weakly absorbed long wavelength photons (? > 900 nm); (3) …
White Light Continuum For Broadband Nonlinear Spectroscopy, Trenton Ensley
White Light Continuum For Broadband Nonlinear Spectroscopy, Trenton Ensley
Electronic Theses and Dissertations
Supercontinuum (SC) generation, oftentimes referred to as white-light continuum (WLC), has been a subject of interest for more than 40 years. From the first observation of WLC in condensed media in the early 1970s to the first observation of WLC in gases in the mid-1980s, much work has been devoted to developing a framework for understanding the complex nature of this phenomenon as well as discovering its utility in various applications. The main effort of this dissertation is to develop a WLC for the purpose of broadband nonlinear spectroscopy and use it in spectroscopic measurements. The ability to generate a …