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Articles 1 - 28 of 28
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Of Muslim Persuasion: The Politics Of Convivencia In Ceuta, Spain, Gabriel Alejandro Torres Colón
Of Muslim Persuasion: The Politics Of Convivencia In Ceuta, Spain, Gabriel Alejandro Torres Colón
Anthropology ETDs
This dissertation examines everyday interactions and political struggles between self-identified Christians and Muslims in the North African Spanish exclave of Ceuta. I explore how each group envisions themselves as part of a local and national community, and then I consider how such visions affect local political processes in everyday life and institutional politics. This dissertation brings a political anthropological perspective to the study of multiculturalism and presents a theoretical perspective for the study of difference in various political contexts.
A Hierarchical Group Model For Programming Sensor Networks, James Horey
A Hierarchical Group Model For Programming Sensor Networks, James Horey
Computer Science ETDs
A hierarchical group model that decouples computation from hardware can characterize and aid in the construction of sensor network software with minimal overhead. Future sensor network applications will move beyond static, homogeneous deployments to include dynamic, heterogeneous elements. These sensor networks will also gain new users, including casual users who will expect intuitive interfaces to interact with sensor networks. To address these challenges, a new computational model and a system implementing the model are presented. This model ensures that computations can be readily reassigned as sensor nodes are introduced or removed. The model includes methods for communication to accommodate these …
1.2-Micron Multi-Section Quantum Dot Superluminescent Diodes, Therese Saiz
1.2-Micron Multi-Section Quantum Dot Superluminescent Diodes, Therese Saiz
Electrical and Computer Engineering ETDs
Superluminescent diodes (SLD) with a center wavelength of 1.2μm are of interest for use in medical imaging of skin tissue especially in the field of optical coherence tomography (OCT). In this thesis a ridge-waveguide multi-section quantum dot SLD that emits at 1.2μm with a bandwidth greater than 100nm and a power greater than 0.2mW is presented. The multi-section SLD allows simultaneous tuning of the ground state emission and excited state emission, resulting in wide bandwidth and high power. Theoretical equations describing the intensity output of the multi-section SLD configuration are presented. It is found that these equations are able to …
Minimally Invasive Capacitive Micromachined Ultrasonic Transducers Array For Biomedical Applications, Xiaoyang Cheng
Minimally Invasive Capacitive Micromachined Ultrasonic Transducers Array For Biomedical Applications, Xiaoyang Cheng
Electrical and Computer Engineering ETDs
Ultrasound covers a broad range of applications from underwater exploration and nondestructive evaluation of materials to medical diagnosis and treatment. The ultrasonic transducer plays an important role in determining the resolution, sensitivity, as well as other critical diagnostic capabilities of an ultrasonic detection or imaging system. Currently piezoelectric ultrasonic transducers dominate the market. The device performance of the piezoelectric ultrasonic transducer in medical applications is limited by the material properties and related electrical and acoustic impedance match issues. The fabrication of piezoelectric transducer array requires meticulous handcrafting. It is difficult and expensive to fabricate densely populated piezoelectric array. The Capacitive …
Attachment And Bonding: Correlations Between Relationship And Anxiety Among Adult College Students, Ellen Witter Armbruster
Attachment And Bonding: Correlations Between Relationship And Anxiety Among Adult College Students, Ellen Witter Armbruster
Individual, Family, and Community Education ETDs
This study investigated the relationships between adult attachment style, memories of early bonding experiences, and five different types of anxiety. The participants were 201 undergraduate psychology students, whose attachment styles, early bonding memories, and tendency toward the five anxiety types were measured through the use of self-report instruments. Analyses were performed to address the three research questions: 1) What is the relationship between attachment style and quality of early interactions with caregivers?; 2) What is the relationship between tendency toward specific types of anxiety and attachment style?; and 3) What is the relationship between tendency toward specific types of anxiety …
The Effects Of Non-Uniform Illumination On The Performance Of Series Connected Photovoltaic Arrays, Jason Shelton
The Effects Of Non-Uniform Illumination On The Performance Of Series Connected Photovoltaic Arrays, Jason Shelton
Electrical and Computer Engineering ETDs
Optical power transfer has several advantages that make this technology useful in many applications. Optical power transfer is immune to the noise generating effects of Radio Frequency (RF) and Electromagnetic Interference (EMI). Transferring power optically also has the benefit of generating electricity in regions where electrical isolation is required. Using Series Connected Photovoltaic Arrays (SCPA) for voltage conversion has the advantage in that high voltage can be directly generated in a small volume. These advantages have led to applications in which the optical power is transferred over a fiber optic and converted to electrical power by using an SCPA. Fiber …
Observation Of High-Lying Resonances In The H- Ion, Philip G. Harris
Observation Of High-Lying Resonances In The H- Ion, Philip G. Harris
Physics & Astronomy ETDs
This dissertation reports the observation of several series of resonances, for which both electrons are in excited states, in the photodetachment cross section of H-. These P doubly-excited states interfere with the continuum in which they are embedded, and appear as dips in the production cross section of excited neutral hydrogen. The experiment was performed by intersecting an 800 MeV H- beam with a (266 nm) laser beam at varying angles; the relativistic Doppler shift then 'tuned' the photon energy in the barycentric frame. The process was observed by using a magnet strong enough to strip the electrons from the …
Terahertz Photomixing Spectroscopy Of Two-Dimensional Semiconductor Plasmons, Todd Barrick
Terahertz Photomixing Spectroscopy Of Two-Dimensional Semiconductor Plasmons, Todd Barrick
Electrical and Computer Engineering ETDs
This thesis reports the findings of terahertz photomixer spectroscopy performed on plasmonic grating-gate detectors made from high mobility two-dimensional electron gas (2DEG) material. In recent years, these detectors have seen significant improvements in sensitivity and currently exhibit a noise equivalent power of 10^-8 W/sqrt(Hz) However, further improvements are essential for these detectors to become truly useful; the ultimate goal being a NEP < 10^-10 W/sqrt(Hz) To this end, it is necessary to understand the physical properties of the mechanism underlying the detectors photoresponse, namely plasmons. Although two-dimensional plasmons were first observed in semiconductors in 1978, to date, their physical properties, for example scattering and absorption cross section, are relatively unknown. The primary purpose of this work is to develop a measurement system capable of revealing these properties and utilize this system to understand the absorption of radiation by two-dimensional plasmons. By no means will the study of plasmonic properties using this system end when this work is completed. Rather, this work lays the foundation for years of future research in this field.
Techniques For High-Speed Direct Modulation Of Quantum Dot Lasers, Yan Li
Techniques For High-Speed Direct Modulation Of Quantum Dot Lasers, Yan Li
Optical Science and Engineering ETDs
As a major component of optical transmitters, directly-modulated semiconductor lasers are widely used in todays fiber optical link systems by taking its advantage of their low cost, compact size and low power consumption. In this work, techniques to improve the high frequency modulation characteristics of semiconductor lasers with a low-dimensional active region medium, specifically quantum dots (QDs), are studied. These techniques include a p-doped active region in single-section QD lasers, the gain-lever effect in two-section lasers and the injection-locking technique. Firstly, the modulation performances of p-doped InAs/GaAs QD lasers were studied. Contrary to the theoretical predictions, the modulation efficiency and …
Experimental Characterization Of Cr4+:Yag Passively Q-Switched Cr:Nd:Gsgg Lasers And Comparison With A Simple Rate Equation Model, Nathan Longbotham
Experimental Characterization Of Cr4+:Yag Passively Q-Switched Cr:Nd:Gsgg Lasers And Comparison With A Simple Rate Equation Model, Nathan Longbotham
Optical Science and Engineering ETDs
This thesis presents a study on the comparison and anlysis of a laser rate equation model and the laboratory performance of passively Q-switched microlasers. The laser rate equation model describes the development of a top hat gain distribution taking into account the excited state absorption of the passive Q-switch. The lasers examined are Cr:Nd:GSGG lasers passively Q-switched by a Cr4+:YAG crystal. This work will focus on the performance of these lasers as a function of two key design parameters, the passive Q-switch initial transmission (T0) and laser resonator output coupling (ROC), when values are varied over a wide range. Four …
Inas/Ga(In)Sb Superlattice Based Infrared Detectors Using Nbn Design, Greg Bishop
Inas/Ga(In)Sb Superlattice Based Infrared Detectors Using Nbn Design, Greg Bishop
Electrical and Computer Engineering ETDs
Infrared detectors in the mid-wave infrared (MWIR) (3-5μm) and long-wave infrared (LWIR) (8-12μm) have many applications in military, industrial and medical fields. The state-of-the-art photodetectors based on Hg1-xCdxTe (MCT) have large signal over noise ratio and their bandgap can be tuned to span 1-32 μm wavelength range. However, large tunneling and Auger dark currents due to low electron effective mass in MCT detectors require operation at cryogenic temperatures (77-100 K). The cooling requirement limits the lifetime, adds weight and expense and increases the power consumption of the infrared system. There is a concerted effort to develop photonic detectors operating at …
Bpsk System Analysis Using Mems Filters, David Ho
Bpsk System Analysis Using Mems Filters, David Ho
Electrical and Computer Engineering ETDs
For some military applications, there exists a need for small custom radios. These radios need to be able to survive extreme environments and transmit the necessary data. This can be achieved by using banks of micromechanical filters. These small filters are post-CMOS compatible, allowing hundreds of high-Q filters to be incorporated over a typical RF transceiver die. Selection of these filters allows the band, channel, and bandwidth to be rapidly changed in operation. Having integrated Microelectromechanical Systems (MEMS) filters eliminates the need for off-chip components such as crystal references and Surface Acoustic Wave (SAW) filters. This allows for smaller, low …
Semiconductor Yield Analysis And Prediction Using A Stochastic Layout Sensitivity Model, Rani S. Ghaida
Semiconductor Yield Analysis And Prediction Using A Stochastic Layout Sensitivity Model, Rani S. Ghaida
Electrical and Computer Engineering ETDs
Spot defects represent the main challenge for enhancement of semiconductor manufacturing yield. As a result, the yield of modern integrated circuits is associated with the layout sensitivity to defects. The term layout sensitivity' is defined as the ratio of 'critical area', i.e. part of the layout in which a defect must be placed to cause a functional failure of the device, to the overall layout area. Semiconductor yield models are traditionally based on the analysis of the 'critical area'. Such models give accurate results; however, critical area analysis requires massive computations that render these models effort and time consuming. The …
Entry And Trafficking Of Human Papillomavirus Type 31 Into Human Keratinocytes, Jessica Smith
Entry And Trafficking Of Human Papillomavirus Type 31 Into Human Keratinocytes, Jessica Smith
Biomedical Sciences ETDs
Human papillomaviruses (HPVs) are small, nonenveloped double stranded DNA viruses that display a strict species and cell type tropism for human epithelial cells. The association between high-risk HPV types and cervical cancer is well established. Additionally, HPVs have been implicated as cofactors in development of several other epithelial cancer types. The difficulty associated with producing infectious HPV stocks, coupled with the complexity of detecting infection using standard virological methods has hindered research into some basic aspects of HPV biology. Recent advances have allowed for the production of high yield stocks of HPV particles for use in infectivity studies and has …
The Rna Binding And Rna Chaperone Activity Of Sin Nombre Virus Nucleocapsid, Bradley Brown
The Rna Binding And Rna Chaperone Activity Of Sin Nombre Virus Nucleocapsid, Bradley Brown
Biomedical Sciences ETDs
Sin Nombre Virus (SNV) is a member of the hantavirus genus in the Bunyaviridae family. Hantaviruses contain a tripartite negative sense RNA genome with individual segments that form panhandle structures through intramolecular interaction between the 5 and 3' termini. This panhandle structure is recognized at high affinity by trimeric viral nucleocapsid protein (N), and this interaction is likely to be important for specific encapsidation of viral RNA (vRNA) into nucleoprotein complexes in cells, for incorporation of vRNA into assembling virus particles, and for initiation of genomic vRNA replication. N is also capable of unwinding RNA/RNA duplexes as an RNA chaperone. …
Refining Models Of Crustal Growth And Evolution In Southwestern Laurentia With Paired U-Pb And Lu-Hf Analyses Of Igneous And Detrital Zircon, Mark E. Holland
Refining Models Of Crustal Growth And Evolution In Southwestern Laurentia With Paired U-Pb And Lu-Hf Analyses Of Igneous And Detrital Zircon, Mark E. Holland
Earth and Planetary Sciences ETDs
The origin and evolution of continental crust is a fundamental and debated topic in geoscience. For over thirty years, Proterozoic crust of the southwestern United States has been a field laboratory for studying orogenic processes in the middle crust, and the growth of continental lithosphere via accretionary orogenesis. Three distinct crustal provinces are delineated based on differences in isotopic, structural, and geochronologic characteristics. To address questions about the origin of each province, this dissertation is composed of three chapters that present new U-Pb and Lu-Hf isotope analysis of plutonic, volcanic, and detrital zircon from the oldest known rocks in each …
'Bajo Su Sombra': The Narration And Reception Of Colonial Urban Space In Early Nineteenth-Century Havana, Cuba, Paul Barrett Niell
'Bajo Su Sombra': The Narration And Reception Of Colonial Urban Space In Early Nineteenth-Century Havana, Cuba, Paul Barrett Niell
Art & Art History ETDs
In early nineteenth-century Havana, Cuba, a small commemorative monument was erected on the Plaza de Armas to honor the site of the city's founding. Through academic history painting, Neoclassical architecture, and the appropriation of symbolic urban space, this memorial reconstructed the sixteenth-century history of the city for nineteenth-century audiences. This addition to the plaza could be seen as an extension of the Bourbon Reforms, which aimed to modernize the city by introducing public works and pedagogical methods that would make this Cuban colony function more efficiently in the insterests of Spain. However, upon closer examination, the memorial for the plaza …
An Appreciative Paradigm Of Learning Persistence And Success In Online Courses, Carol Anger Richmond
An Appreciative Paradigm Of Learning Persistence And Success In Online Courses, Carol Anger Richmond
Organization, Information and Learning Sciences ETDs
There is a need for a better understanding of persistence in online environments from a positive perspective. The appreciative inquiry (AI) model challenges the traditional problem based paradigm with an affirmative approach to embrace challenges in a positive light. This study uses an appreciative inquiry approach to grounded theory analysis to study online learning persistence and success. The purpose of this qualitative grounded theory study was: 1) to discover the themes and factors that emerge from an appreciative inquiry of online learner persistence; 2) to identify the meaning of persistence for online students; 3) to create provocative propositions of the …
Volatile Chemistry, And Nitrogen Sources And Fluxes, In Subduction Zones : Insights From The Izu-Bonin-Mariana Arc, Euan Mitchell
Volatile Chemistry, And Nitrogen Sources And Fluxes, In Subduction Zones : Insights From The Izu-Bonin-Mariana Arc, Euan Mitchell
Earth and Planetary Sciences ETDs
A systematic study of the geochemistry of volatiles being emitted from the active volcanic front of the Izu-Bonin-Mariana (IBM) arc was undertaken in order to investigate the sources, flux, and mass balance of nitrogen across this 'cool' convergent margin. The IBM arc is an ideal location to study volatile recycling in subduction zones as it is an intra-oceanic convergent margin (IOCM), where the entire sedimentary sequence is subducted and where a number of parameters, including sediment composition, slab dip and slab age, vary systematically along strike of the arc. Volcanic emissions are typical of convergent margin volcanoes, and are dominated …
The Inverse Kinetics Method And Pid Compensation Of The Annular Core Research Reactor, Benjamin Garnas
The Inverse Kinetics Method And Pid Compensation Of The Annular Core Research Reactor, Benjamin Garnas
Electrical and Computer Engineering ETDs
This thesis explores the development of a model describing the Annular Core Research Reactor (ACRR), the application of the inverse kinetics method to calculate the current reactivity level within the ACRR model, and the development of a PID compensator to automatically control the reactivity level within the model and thus controlling the power level.
Quantum Dot Gain-Lever Laser Diode, Nader Naderi
Quantum Dot Gain-Lever Laser Diode, Nader Naderi
Electrical and Computer Engineering ETDs
Semiconductor quantum dot (QD) lasers are competitive candidates for many applications such as high-speed long-haul optical communication systems. This is due to their superior lasing characteristics (compared to conventional quantum well (QW) lasers) and also their potential for high differential gain and direct modulation with negligible chirp. Recently, substantial efforts have been made to improve the modulation characteristics of QD semiconductor lasers such as enhancing the modulation efficiency and improving the overall modulation bandwidth. The gain lever effect is a method used to enhance the efficiency of amplitude modulation and optical frequency modulation at microwave frequencies by taking advantage of …
Advanced Parallel Magnetic Resonance Imaging Methods With Applications To Mr Spectroscopic Imaging, Ricardo Otazo
Advanced Parallel Magnetic Resonance Imaging Methods With Applications To Mr Spectroscopic Imaging, Ricardo Otazo
Electrical and Computer Engineering ETDs
Parallel magnetic resonance imaging offers a framework for acceleration of conventional MRI encoding using an array of receiver coils with spatially-varying sensitivities. Novel encoding and reconstruction techniques for parallel MRI are investigated in this dissertation. The main goal is to improve the actual reconstruction methods and to develop new approaches for massively parallel MRI systems that take advantage of the higher information content provided by the large number of small receivers. A generalized forward model and inverse reconstruction with regularization for parallel MRI with arbitrary k-space sub-sampling is developed. Regularization methods using the singular value decomposition of the encoding matrix …
Modeling The Effects Of Proton Irradiation [On] Cigs Solar Cells, Jacob Dunken
Modeling The Effects Of Proton Irradiation [On] Cigs Solar Cells, Jacob Dunken
Electrical and Computer Engineering ETDs
The space environment is very harsh on photovoltaic devices. Solar protons (hydrogen ions) cause large numbers of vacancies, which act as recombination centers at deep levels and can create compensating defects that reduce the acceptor concentration at shallow levels in semiconductors. This in turn, can reduce the output power generated by photovoltaic devices. Damage can also occur from atomic oxygen, plasma discharges and electron irradiation. Solar arrays have to be manufactured to produce more power than necessary so that the solar array will still produce the needed amount of power after degradation occurring from charged particle irradiation. A major challenge …
Characterization Of Spectral Response Of A Quantum Dots-In-A-Well Infrared Focal Plane Array, Michael Lenz Ii
Characterization Of Spectral Response Of A Quantum Dots-In-A-Well Infrared Focal Plane Array, Michael Lenz Ii
Electrical and Computer Engineering ETDs
Spectral characterization of a novel single bump, two-color InAs/InGaAs quantum dots-in-a-well (DWELL) infrared focal plane array (FPA) was undertaken and reported here. The hypothesis of the study is that the FPA will exhibit bias-tunable spectral response. Broadband and two-color performance measures of the DWELL FPA are discussed and presented. The DWELL structure is a hybrid of a quantum dot (QD) photodetector consisting of an active region composed of InAs quantum dots embedded in InGaAs quantum wells. The DWELL FPA demonstrates mid-wave infrared (MWIR) and long-wave infrared (LWIR) performance believed to be attributed to transitions from bound states in the dot …
Eagle Vision : New Directions In K-12 Gis, Cody Wiley
Eagle Vision : New Directions In K-12 Gis, Cody Wiley
Geography ETDs
Eagle Vision is an NSF-funded three-year project that instructs High School teachers working in tribal schools in GIS and GIT, and in GIS-based curriculum design. Integration of GIS into the secondary level classroom has faced many barriers, and despite extensive efforts on the part of Eagle Vision to circumvent these hurdles, many of them appeared. An additional problem regarding spatial literacy became apparent. Overall, however, the program was successful in increasing use of GIS and GIT, and provided crucial information that will help improve teacher professional training in the area of GIS.
Cooperative Roles Of Geographic Information Science In Identifying Boundary Uncertainty : A Case Study In The Bureau Of Land Management's Manzano Wilderness Study Area, Kathleen Hawkos
Geography ETDs
Advances in the development and accuracy of Geographic Information Science (GIS) in concert with the rapid development of advanced microprocessors and computer software have resulted in widely available survey data. No longer held captive by the discipline of surveying, this data is currently being used by geographers, cartographers, municipal planners and realtors for display and reproduction. Surveying provides the physical and legal basis for boundary delineation while GIS provides the tools to readily yield information from spatial data, and to economically conduct analyses enabling a more comprehensive understanding of boundary issues. A case study in the Bureau of Land Managements …
Analysis And Design Of Reconfigurable Multi-Band Stacked Microstrip Patch Antennas (Msas) For Wireless Applications, Mahmoud Alayesh
Analysis And Design Of Reconfigurable Multi-Band Stacked Microstrip Patch Antennas (Msas) For Wireless Applications, Mahmoud Alayesh
Electrical and Computer Engineering ETDs
There is an increasing demand for smaller low-cost reconfigurable antennas that can be easily integrated with packaging structures. Reconfigurable Microstrip Patch Antennas (MSAs) received great attention in wireless communication systems due to their capability to vary their operating frequency, pattern and polarization. Reconfigurability enables us to accommodate more than one service using the same antenna. This thesis presents the analysis and design of new reconfigurable stacked (MSAs) of operating frequencies in the range of (2-5) GHz. The first new antenna is composed of two layers. The bottom layer is a MSA with two slots designed on each side that can …
Injection Locking Characteristics Of Indium Arsenide Quantum Dash Lasers, Aaron Moscho
Injection Locking Characteristics Of Indium Arsenide Quantum Dash Lasers, Aaron Moscho
Electrical and Computer Engineering ETDs
The study of injection locking characteristics was performed on an InAs Quantum Dash (QDash) semiconductor laser for the first time. The linewidth enhancement factor(α-parameter) of a QDash laser was measured using an injection locking technique that takes advantage of the asymmetry of the injection range. Studies were performed as functions of injecesed photon density, wavelength, and output power. To understand the behavior of the α-parameter versus wavelength, the Hakki-Paoli method, a technique that utilized the below threshold amplified spontaneous emission spectrum, was used to measure the modal gain over 1550 nm to 1573 nm. The α-parameter was found to have …