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Title: Freestanding Holey Thin Films for Renewable Energy Storage.
Creator: Marcus, Kyle, Yang, Yang, Zhai, Lei, Dong, Yajie, University of Central Florida
Abstract / Description: The rapid advancement of portable and wearable technologies has challenged research to improve upon current renewable battery energy storage systems. By using nanotechnology, it is now possible to access more of the energy storage theoretical values that have been unattainable thus far. We have developed a method to create freestanding holey thin films through combinations of electrochemical and chemical vapor deposition (CVD) techniques to be used in renewable energy storage systems....
Show moreThe rapid advancement of portable and wearable technologies has challenged research to improve upon current renewable battery energy storage systems. By using nanotechnology, it is now possible to access more of the energy storage theoretical values that have been unattainable thus far. We have developed a method to create freestanding holey thin films through combinations of electrochemical and chemical vapor deposition (CVD) techniques to be used in renewable energy storage systems. Freestanding thin films promote excellent contact between the residual conductive framework and any functionalized active component specific to the designed material. Without requiring any other additives, the as-prepared freestanding thin films can be mechanically and chemically tuned to allow for use in a wide range of applications. Incorporation of micro- and nano-sized holey structures dramatically enhances the electrochemically active surface area, which is essential for facilitating appropriate reactions in conversion type energy storage systems. Combining the freestanding and holey components with an active layer effectively enhances conductivity and reduces the electron transfer distance at the electrode-electrolyte interface. Herein, two separately designed freestanding holey thin films were successfully used as cathode materials for lithium-sulfur battery (Li-S) and magnesium-ion battery (MIB) energy storage systems.
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Date Issued: 2017
Identifier: CFE0007127, ucf:52304
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007127

Title: Lithium polysulfide battery with improved capacity and cycle performance using carbon black coated free-standing carbon cloth.
Creator: Wei, Zhen, Kushima, Akihiro, Yang, Yang, Feng, Xiaofeng, University of Central Florida
Abstract / Description: Lithium ion batteries (LIBs) have been used in various applications such as portable electronics, grid storages, and electric vehicles (EVs). Despite its commercial success, further advancement of the battery is necessary to satisfy the increasing demands for low-cost and high- performance energy storage devices as LIB is reaching its theoretical limits. Lithium sulfur battery (LSB) is one of the promising candidates for the next generation energy storage technologies. LSB uses sulfur cathode...
Show moreLithium ion batteries (LIBs) have been used in various applications such as portable electronics, grid storages, and electric vehicles (EVs). Despite its commercial success, further advancement of the battery is necessary to satisfy the increasing demands for low-cost and high- performance energy storage devices as LIB is reaching its theoretical limits. Lithium sulfur battery (LSB) is one of the promising candidates for the next generation energy storage technologies. LSB uses sulfur cathode which is a low-cost and earth abundant material with an extremely high theoretical capacity of 2600 Wh kg-1. Although there have been numerous researches aiming to establish the LSB technology, it is still in a development stage. Some of the major challenges are; low-electric conductivity, dissolution of the intermediate lithium-polysulfide reactants, and the low Coulombic efficiency. These issues must be overcome before LSBs can become practical.The objective of this work is to develop an LSB cathode that solves the above issues and contributes to advancing the development of the LSB technology. We focus on improving the electrical conductivity while reducing the shuttle effect, a parasitic reaction of the polysulfides at the anode lithium surface. To achieve this goal, we developed a carbon black coated free-standing carbon cloth. It is infiltrated with a Li2S8-containing catholyte as an active material, and its carbon framework serves as an entrapment of the polysulfides. The electrode composite enabled high- sulfur-loading, and its high surface area increased the reaction sites allowing the effective utilization of the sulfur that lead to the high capacity. It also showed high capacity retention by successfully trapping the polysulfides within the electrode. This facile and low-cost solution contributes to the realization of the LSBs.
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Date Issued: 2019
Identifier: CFE0007873, ucf:52791
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007873

Title: nanoengineered energy harvesting and storage devices.
Creator: Li, Chao, Thomas, Jayan, Zhai, Lei, Yang, Yang, Gesquiere, Andre, Dong, Yajie, Sun, Wei, University of Central Florida
Abstract / Description: Organic and perovskite solar cells have recently attracted significant attention due to itsflexibility, ease of fabrication and excellent performance. In order to realize even betterperformance for organic and perovskite solar cells, rejuvenated effort towards developingnanostructured electrodes and high quality active layer is necessary.In this dissertation, several strategic directions of enhancing the performance of organicand perovskite solar cells are investigated. An introduction and...
Show moreOrganic and perovskite solar cells have recently attracted significant attention due to itsflexibility, ease of fabrication and excellent performance. In order to realize even betterperformance for organic and perovskite solar cells, rejuvenated effort towards developingnanostructured electrodes and high quality active layer is necessary.In this dissertation, several strategic directions of enhancing the performance of organicand perovskite solar cells are investigated. An introduction and background of organic andperovskite solar cells, which includes motivation, classification and working principles,nanostructured electrode materials and solvent effect on active materials, and devices fabrication,are presented. A facile method, called Spin-on Nanoprinting (SNAP), to fabricate highly orderedZnO-AgNW-ZnO electrode is introduced to enhance the performance of organic solar cell.Subsequently, a ternary solvent method is developed to fabricate high Voc thieno[3,4-b]thiophene/benzodithiophene (PTB7) and indene-C60 bisadduct (ICBA)solar cells. Theperformance of the devices improved about 20% compared to those made by binary solventmethod. In order to understand the fundamental properties of the materials ruling theperformance of the PSCs tested, AFM-based nanoscale characterization techniques includingPulsed-Force-Mode AFM (PFM-AFM) and Mode-Synthesizing AFM (MSAFM) are introduced.These methods are used to study the morphology and physical properties of the structuresconstitutive of the active layers of the PSCs. Conductive-AFM (cAFM) studies reveal localvariations in conductivity in the donor and acceptor phases as well as an increase in photocurrentmeasured in the PTB7:ICBA sample obtained with the ternary solvent processing technique.Moreover, efficient perovskite solar cells with good transparency in the visible wavelength rangehave been developed by a facile and low-temperature PCBM-assisted perovskite growth method.This method results in the formation of perovskite-PCBM hybrid material at the grain boundaries which is observed by EELS mapping and confirmed by steady-state photoluminescence (PL)spectra and transient photocurrent (TP) measurements. This method involves fewer steps andtherefore is less expensive and time consuming than other reported methods. In addition, wereport an all solid state, energy harvesting and storing (ENHANS) filament which integratesperovskite solar cell (PSC) on top of a symmetric supercapacitor (SSC) via a copper filamentwhich works as a shared electrode for direct charge transfer. Developing ENHANS on a copperfilament provides a low-cost solution for flexible self-sufficient energy systems for wearablesand other portable devices. Finally, a summary of this dissertation as well as some potentialfuture directions are presented.
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Date Issued: 2016
Identifier: CFE0006693, ucf:51912
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006693

Title: REAL-TIME TRAJECTORY PLANNING FOR GROUNDAND AERIAL VEHICLES IN A DYNAMIC ENVIRONMENT.
Creator: Yang, Jian, Qu, Zhihua, University of Central Florida
Abstract / Description: In this dissertation, a novel and generic solution of trajectory generation is developed and evaluated for ground and aerial vehicles in a dynamic environment. By explicitly considering a kinematic model of the ground vehicles, the family of feasible trajectories and their corresponding steering controls are derived in a closed form and are expressed in terms of one adjustable parameter for the purpose of collision avoidance. A collision-avoidance condition is developed for the dynamically...
Show moreIn this dissertation, a novel and generic solution of trajectory generation is developed and evaluated for ground and aerial vehicles in a dynamic environment. By explicitly considering a kinematic model of the ground vehicles, the family of feasible trajectories and their corresponding steering controls are derived in a closed form and are expressed in terms of one adjustable parameter for the purpose of collision avoidance. A collision-avoidance condition is developed for the dynamically changing environment, which consists of a time criterion and a geometrical criterion. By imposing this condition, one can determine a family of collision-free paths in a closed form. Then, optimization problems with respect to different performance indices are setup to obtain optimal solutions from the feasible trajectories. Among these solutions, one with respect to the near-shortest distance and another with respect to the near-minimal control energy are analytical and simple. These properties make them good choices for real-time trajectory planning. Such optimal paths meet all boundary conditions, are twice differentiable, and can be updated in real time once a change in the environment is detected. Then this novel method is extended to 3D space to find a real-time optimal path for aerial vehicles. After that, to reflect the real applications, obstacles are classified to two types: "hard" obstacles that must be avoided, and "soft" obstacles that can be run over/through. Moreover, without losing generality, avoidance criteria are extended to obstacles with any geometric shapes. This dissertation also points out that the emphases of the future work are to consider other constraints such as the bounded velocity and so on. The proposed method is illustrated by computer simulations.
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Date Issued: 2008
Identifier: CFE0002031, ucf:47594
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002031

Title: THE EFFECT OF TECHNOLOGY ACCEPTANCE ON UNDERGRADUATE STUDENTS' USAGE OF WEBCT AS A COLLABORATIVE TOOL.
Creator: Yang, Huei-Hsuan, Sivo, Stephen A., University of Central Florida
Abstract / Description: The purpose of this research study was to use the Technology Acceptance Model (Pan, 2003) for re-examination of the relationships between students' attitude toward the use of WebCT and the relevance of the actual usage in light of social presence and sociability. By using Technology Acceptance Model (TAM) developed by F. Davis (1989), this study focused on variables such as perceived usefulness, perceived ease of use, computer self-efficacy, subjective norms, attitude and actual use of...
Show moreThe purpose of this research study was to use the Technology Acceptance Model (Pan, 2003) for re-examination of the relationships between students' attitude toward the use of WebCT and the relevance of the actual usage in light of social presence and sociability. By using Technology Acceptance Model (TAM) developed by F. Davis (1989), this study focused on variables such as perceived usefulness, perceived ease of use, computer self-efficacy, subjective norms, attitude and actual use of WebCT to account for the effect towards the achievement in the exam which is an outcome variable. The data were collected over three different time periods during the spring semester of 2007 to find how these results changed over time. The participants were the students who enrolled in the business marketing course (Principle of marketing) at the University of Central Florida in spring, 2007. The course was divided to three sections: on-campus, video-streaming and online classes. Although there were three different delivery methods, there was only one instructor and they used same material for all sections so the results were used to compare the differences from three classes. The study was conducted by using instruments to measure perceived usefulness, perceived ease of use, computer self-efficacy, subjective norms, actual use, attitude, sociability, social presence and an additional demographic instrument.
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Date Issued: 2007
Identifier: CFE0001761, ucf:47262
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001761

Title: ADVANCED CODING AND MODULATION FOR ULTRA-WIDEBAND AND IMPULSIVE NOISES.
Creator: Yang, Libo, Wei, Lei, University of Central Florida
Abstract / Description: The ever-growing demand for higher quality and faster multimedia content delivery over short distances in home environments drives the quest for higher data rates in wireless personal area networks (WPANs). One of the candidate IEEE 802.15.3a WPAN proposals support data rates up to 480 Mbps by using punctured convolutional codes with quadrature phase shift keying (QPSK) modulation for a multi-band orthogonal frequency-division multiplexing (MB-OFDM) system over ultra wideband (UWB) channels....
Show moreThe ever-growing demand for higher quality and faster multimedia content delivery over short distances in home environments drives the quest for higher data rates in wireless personal area networks (WPANs). One of the candidate IEEE 802.15.3a WPAN proposals support data rates up to 480 Mbps by using punctured convolutional codes with quadrature phase shift keying (QPSK) modulation for a multi-band orthogonal frequency-division multiplexing (MB-OFDM) system over ultra wideband (UWB) channels. In the first part of this dissertation, we combine more powerful near-Shannon-limit turbo codes with bandwidth efficient trellis coded modulation, i.e., turbo trellis coded modulation (TTCM), to further improve the data rates up to 1.2 Gbps. A modified iterative decoder for this TTCM coded MB-OFDM system is proposed and its bit error rate performance under various impulsive noises over both Gaussian and UWB channel is extensively investigated, especially in mismatched scenarios. A robust decoder which is immune to noise mismatch is provided based on comparison of impulsive noises in time domain and frequency domain. The accurate estimation of the dynamic noise model could be very difficult or impossible at the receiver, thus a significant performance degradation may occur due to noise mismatch. In the second part of this dissertation, we prove that the minimax decoder in \cite, which instead of minimizing the average bit error probability aims at minimizing the worst bit error probability, is optimal and robust to certain noise model with unknown prior probabilities in two and higher dimensions. Besides turbo codes, another kind of error correcting codes which approach the Shannon capacity is low-density parity-check (LDPC) codes. In the last part of this dissertation, we extend the density evolution method for sum-product decoding using mismatched noises. We will prove that as long as the true noise type and the estimated noise type used in the decoder are both binary-input memoryless output symmetric channels, the output from mismatched log-likelihood ratio (LLR) computation is also symmetric. We will show the Shannon capacity can be evaluated for mismatched LLR computation and it can be reduced if the mismatched LLR computation is not an one-to-one mapping function. We will derive the Shannon capacity, threshold and stable condition of LDPC codes for mismatched BIAWGN and BIL noise types. The results show that the noise variance estimation errors will not affect the Shannon capacity and stable condition, but the errors do reduce the threshold. The mismatch in noise type will only reduce Shannon capacity when LLR computation is based on BIL.
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Date Issued: 2007
Identifier: CFE0001836, ucf:47342
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001836

Title: POSSIBLE USE OF P20 ANTIGEN IN SERODIAGNOSIS OF INFLAMMATORY BOWEL DISEASE.
Creator: Yang, ShinChieh, Naser, Saleh, University of Central Florida
Abstract / Description: Crohn's disease (CD) is an idiopathic, chronic, relapsing inflammatory disorder, which is most commonly involved terminal ileum and colon. The incidence and prevalence of CD has dramatically increased during the last 50 years; however, the etiology and mechanism of this disorder remain unveiled. Besides genetic susceptibility, recent integrated researches investigated the role of environmental triggers such as microflora, measles viruses and mycobacteria in the pathogenesis of CD. The...
Show moreCrohn's disease (CD) is an idiopathic, chronic, relapsing inflammatory disorder, which is most commonly involved terminal ileum and colon. The incidence and prevalence of CD has dramatically increased during the last 50 years; however, the etiology and mechanism of this disorder remain unveiled. Besides genetic susceptibility, recent integrated researches investigated the role of environmental triggers such as microflora, measles viruses and mycobacteria in the pathogenesis of CD. The association between M. avium subsp paratuberculosis (MAP) and CD has been heightened because of clinical resemblance to Johne's disease (JD), a granulomatous enteritis in ruminants caused by MAP. Isolation of MAP from tissue and milk samples from CD patients and from commercial pasteurized milk and dairy products from JD-infected animals implies a possible re-classification of CD as zoonotic disorder. Clinical signs and symptoms of CD are often non-specific and a challenge to distinguish it from other disorders. Current methods for inflammatory bowel disease diagnosis, especially for CD are highly invasive, distressing and expensive. In this study, the recombinant clone pB11 containing 1.1 kb insert, identified from a MAP genomic library constructed in E. coli, expressed a 20 kDa (p20) antigen encoded on 549 bp partial MAP gene with an ORF cloned in frame within pBAD/His cloning vector. Immunoreactivity of p20 was confirmed by Immunoblot. Purified p20 antigen was then used in the development of an enzyme-linked immunosorbent assay (ELISA) for possible serodiagnosis of Inflammatory Bowel Disease (IBD) associated with MAP infection. All variables associated with ELISA test with regard to concentrations, washes and incubations were optimized using hyper immune rabbit t-anti-MAP polyclonal IgG antibodies and sera from CD and non-CD subjects. The cut-off value for positive response was established as 0.3 following the analysis of statistically formulated samples from normal and non-CD subjects. The developed ELISA test was then used to test a blindly coded 2 17 clinical sera. All sera samples were tested in duplicates and in both p20-coated and uncoated micro titer plates. Consequently, 116/134 (87%) CD sera were positive compared to 24/83 (33%) non-CD sera (P<0.05). Specifically anti-MAP IgG was detected in 8/22 (36%) Ulcerative colitis and 16/61 (26%) non-IBD sera. p20-ORF encoding sequence was recloned (pB11/B6) and the expressed protein reactivity remained consistent. Moreover, the full length of the cloned gene was also identified through blast and alignment analysis and predicted to encode 346 amino acids with unknown function and no identity with other known proteins. The latter supports the clinical data, which reflect on the unique characteristics of this antigen. The result so far suggests that the recombinant clone and its subclone derivative may have potential role in serodiagnosis of CD.
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Date Issued: 2004
Identifier: CFE0000089, ucf:46148
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000089

Title: CIRCUIT DESIGN AND RELIABILITY OF A CMOS RECEIVER.
Creator: Yang, Hong, Yuan, Jiann, University of Central Florida
Abstract / Description: This dissertation explores CMOS RF design and reliability for portable wireless receivers. The objective behind this research is to achieve an increase in integration level, and gain more understanding for RF reliability. The fields covered include device, circuit and system. What is under investigation is a multi-band multi-mode receiver with GSM, DCS-1800 and CDMA compatibility. To my understanding, GSM and CDMA dual-mode mobile phones are progressively investigated in industries, and few...
Show moreThis dissertation explores CMOS RF design and reliability for portable wireless receivers. The objective behind this research is to achieve an increase in integration level, and gain more understanding for RF reliability. The fields covered include device, circuit and system. What is under investigation is a multi-band multi-mode receiver with GSM, DCS-1800 and CDMA compatibility. To my understanding, GSM and CDMA dual-mode mobile phones are progressively investigated in industries, and few commercial products are available. The receiver adopts direct conversion architecture. Some improved circuit design methods are proposed, for example, for low noise amplifier (LNA). Except for band filters, local oscillators, and analog-digital converters which are usually implemented by COTS SAW filters and ICs, all the remaining blocks such as switch, LNA, mixer, and local oscillator are designed in MOSIS TSMC 0.35ìm technology in one chip. Meanwhile, this work discusses related circuit reliability issues, which are gaining more and more attention. Breakdown (BD) and hot carrier (HC) effects are important issues in semiconductor industry. Soft-breakdown (SBD) and HC effects on device and RF performance has been reported. Hard-breakdown (HBD) effects on digital circuits have also been investigated. This work uniquely address HBD effects on the RF device and circuit performance, taking low noise amplifier and power amplifier as targets.
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Date Issued: 2004
Identifier: CFE0000212, ucf:46259
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000212

Title: GENERAL INTERFERENCE SUPPRESSION TECHNIQUE FOR DIVERSITY WIRELESS RECEIVERS IN FADING CHANNELS BASED ON INDEPENDENT COMPONENT ANALYSIS.
Creator: Yang, Tianyu, Mikhael, Wasfy, University of Central Florida
Abstract / Description: The area of wireless transceiver design is becoming increasingly important due to the rapid growth of wireless communications market as well as diversified design specifications. Research efforts in this area concentrates on schemes that are capable of increasing the system capacity, providing reconfigurability/reprogrammability and reducing the hardware complexity. Emerging topics related to these goals include Software Defined Radio, Multiple-Input-Multiple-Output (MIMO) Systems, Code...
Show moreThe area of wireless transceiver design is becoming increasingly important due to the rapid growth of wireless communications market as well as diversified design specifications. Research efforts in this area concentrates on schemes that are capable of increasing the system capacity, providing reconfigurability/reprogrammability and reducing the hardware complexity. Emerging topics related to these goals include Software Defined Radio, Multiple-Input-Multiple-Output (MIMO) Systems, Code Division Multiple Access, Ultra-Wideband Systems, etc. This research adopts space diversity and statistical signal processing for digital interference suppression in wireless receivers. The technique simplifies the analog front-end by eliminating the anti-aliasing filters and relaxing the requirements for IF bandpass filters and A/D converters. Like MIMO systems, multiple antenna elements are used for increased frequency reuse. The suppression of both image signal and Co-Channel Interference (CCI) are performed in DSP simultaneously. The signal-processing algorithm used is Independent Component Analysis (ICA). Specifically, the fixed-point Fast-ICA is adopted in the case of static or slow time varying channel conditions. In highly dynamic environment that is typically encountered in cellular mobile communications, a novel ICA algorithm, OBAI-ICA, is developed, which outperforms Fast-ICA for both linear and abrupt time variations. Several practical implementation issues are also considered, such as the effect of finite arithmetic and the possibility of reducing the number of antennas.
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Date Issued: 2004
Identifier: CFE0000231, ucf:46260
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000231

Title: ESSAYS ON CORPORATE GOVERNANCE.
Creator: Yang, Minhua, Frye, Melissa, University of Central Florida
Abstract / Description: This dissertation is composed by two essays that explore the changes in corporate governance around the passage of Sarbanes-Oxley (SOX) 2002. In the first essay, I examine the relation between board structure and compensation as a bargaining game between the board and the CEO. Bargaining game theories describe an endogenous process of determining the structure of director and CEO compensation. The Sarbanes-Oxley Act (SOX) altered the equilibrium of power between the board and CEO by changing...
Show moreThis dissertation is composed by two essays that explore the changes in corporate governance around the passage of Sarbanes-Oxley (SOX) 2002. In the first essay, I examine the relation between board structure and compensation as a bargaining game between the board and the CEO. Bargaining game theories describe an endogenous process of determining the structure of director and CEO compensation. The Sarbanes-Oxley Act (SOX) altered the equilibrium of power between the board and CEO by changing the monitoring role of the board. SOX essentially provides a natural experiment to test how a shock to the bargaining game alters the balance of power between directors and the CEO. Using the ratio of director compensation to CEO compensation to proxy for bargaining power, I find a significant increase following the passage of SOX, consistent with directors gaining bargaining advantage. Moreover, firms with strong shareholder rights exhibit even greater evidence of power shifting to the directors. Overall, the results suggest that directors gain more power relative to the CEO in determining compensation plans and strong shareholder rights help firms to align directors' incentives with those of shareholders. In the second essay, I examine the relation between CEO compensation structure and acquirer returns. In the literature, researchers find that executive compensation structures influence corporate acquisition decisions. Equity-based executive compensation should reduce the non-value-maximizing behavior of acquiring managers. A series of corporate reforms such as SOX and the FASB expensing rule affected the structure of CEO equity-based compensation. I find a significant increase in CEO restricted stock compensation and a significant decrease in CEO option-based compensation following these reforms. I also find that CEOs with strong managerial power are more likely to receive more restricted stock in their compensation package after the 2002 reforms. Finally, I find a significant positive relation between the restricted stock compensation of acquiring firm CEOs and abnormal stock returns after 2002. This provides empirical support on the effectiveness of the shift away from options towards restricted stock in executive compensation packages. Restricted stock is associated with better merger decisions.
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Date Issued: 2009
Identifier: CFE0002916, ucf:48009
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002916

Title: PHYSICAL PROPERTIES OF WAVE SCATTERING BY CHIRAL PERIODIC STRUCTURE.
Creator: Yang, Xiaomin, Wu, Xinzhang, University of Central Florida
Abstract / Description: Attention has been focused on electromagnetic chirality and its potential applications to microwave, millimeter wave and optical wave devices. In this work, wave propagation through a chiral periodic structure with arbitrary shape is investigated. Although perturbation theory and coupled-mode theory have been used to analyze chiral periodic structure, those are approximate methods and can only be used for low frequency applications. In this work, the rigorous mode-matching method is used to...
Show moreAttention has been focused on electromagnetic chirality and its potential applications to microwave, millimeter wave and optical wave devices. In this work, wave propagation through a chiral periodic structure with arbitrary shape is investigated. Although perturbation theory and coupled-mode theory have been used to analyze chiral periodic structure, those are approximate methods and can only be used for low frequency applications. In this work, the rigorous mode-matching method is used to solve the problem. Staircase approximation is introduced to change the curved structure to a multilayer structure. The field solutions in the uniform air regions and unbounded air-chiral periodic array have been derived. Finite element method is used to solve the eigenvalues and eigenfunctions in the periodic chiral slabs. Mode-matching method is used at the boundaries to calculate the scattering characteristics. Numerical results are displayed to explain the underlying physical properties of the chiral periodic structure. The Wood's anomalies at high frequencies have been investigated and explained by the excitation of leaky waves guided along the periodic layer. The influence of frequency, chirality parameter, incident angle, curve shape and period are discussed. It has been found that the chiral periodic structure can be used as both a frequency selective device and a mode conversion device. First, the derivation and numeric calculation were done with the principal plane incidence. Then, the discussion was extended to the more general case of oblique incidence by the coordinate transformation.
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Date Issued: 2009
Identifier: CFE0002964, ucf:47987
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002964

Title: CHARACTERIZATION AND AQUEOUS COLLOIDAL PROCESSING OF TUNGSTEN NANO-POWDERS.
Creator: Yang, Zhengtao, Sohn, Yongho, University of Central Florida
Abstract / Description: Extensive attention has been paid to consolidate nanoparticles into nanocrystalline components that possess better properties than their coarse-grained counterparts. Nanocrystalline monolithic tungsten (W) has been envisaged to possess better properties than coarse-grained tungsten and to improve the performance of many military components. Commercially available nano-W powders were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy...
Show moreExtensive attention has been paid to consolidate nanoparticles into nanocrystalline components that possess better properties than their coarse-grained counterparts. Nanocrystalline monolithic tungsten (W) has been envisaged to possess better properties than coarse-grained tungsten and to improve the performance of many military components. Commercially available nano-W powders were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and Brunauer, Emmett, and Teller (BET) measurement. While the bulk of nano-W powders consisted of bcc-W as confirmed by XRD and TEM, much of their surface consisted of WO3 with traces of WO2 and WC. Despite the irregular morphology and agglomerates greater than 1 m in size, the diameter of individual nano-W powders ranged from 30 to 100 nm with a surface area of 10.4 m2/g. To obtain green bodies of higher densities and more homogeneous microstructures after consolidation, W nanopowders were de-agglomerated in water and slip cast in plaster molds. De-agglomeration in water was conducted by repeated ultrasonication, washing, centrifuge and pH adjustment. The change in particle size and morphology was examined via SEM. After the initial surface oxide was removed by repeated washing, the reactivity of W nanoparticles to water was somewhat inhibited. Increasing the number of cycles for ultrasonication and washing increased the pH, the degree of de-agglomeration and the stability of W suspension. The zeta potential was more negative with increasing pH and most negative at pH values close to 5. Viscosity also decreased with increasing pH and reached a minimum at a pH 5. To obtain the highest solid loading with the lowest viscosity, the pH value of W suspension was adjusted to 5 using aqueous tetramethylammonium hydroxide solutions. The relative density of the slip cast increased with longer ultrasonic time, increasing slurry pH up to 5, and consequent increase in solids loading. Smaller particles were separated from larger ones by ultrasonication, washing with water and centrifugation. At a 27.8 vol.% solids loading, the size-separated fine W slurry was slip cast into pellets with relative green densities up to 41.3 % and approximate particle sizes of 100 nm. W powders were also ultrasonicated in aqueous poly (ethyleneimine) (PEI) solutions with various concentrations. SEM examinations of particle sizes showed that 1 wt.% PEI led to the optimum dispersion and ultrasonication for longer time with a low power resulted in better dispersion. 0.5 g of W powders were ultrasonicated in 10 ml aqueous poly (allylamine hydrochloride) (PAH) solutions with molar concentrations ranging from 0.01 to 0.05 M. W suspensions with 0.03 M and 0.04 M PAH after two washing cycles showed improved dispersion. Cold isostatic pressing can further increase the green density following slip casting. Sintered slip casts made from de-agglomerated nanoparticle W showed a lower density, more uniform microstructure, smaller grains and smaller pores than the sintered dry pressed pellets.
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Date Issued: 2009
Identifier: CFE0002706, ucf:48144
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002706

Title: SELF-ASSEMBLY AND PHOTOPHYSICS OF SELECTED ORGANIC MATERIALS AND TWO-PHOTON BIOIMAGING WITH PROFLUORESCENT NITROXIDES, POLYELECTROLYTE NANOPARTICLES, AND SQUARAINE PROBES.
Creator: Ahn, Hyo-Yang, Belfield, Kevin, University of Central Florida
Abstract / Description: Two-photon absorption and upconverted fluorescence has been utilized in a variety of applications in pure science and engineering. Multiphoton-based techniques were used in this research in order to understand photophysical and chemical characteristics of several fluorescent dyes and to demonstrate some of their key applications. Two-photon fluorescence microscopy (2PFM) has become a powerful technique in bio-photonics for non-invasive imaging in the near-infrared (NIR) region (700~1000 nm)...
Show moreTwo-photon absorption and upconverted fluorescence has been utilized in a variety of applications in pure science and engineering. Multiphoton-based techniques were used in this research in order to understand photophysical and chemical characteristics of several fluorescent dyes and to demonstrate some of their key applications. Two-photon fluorescence microscopy (2PFM) has become a powerful technique in bio-photonics for non-invasive imaging in the near-infrared (NIR) region (700~1000 nm) that often results in less photobleaching. In Chapter 1, there is a brief introduction to fluorescence, examples of fluorescence materials, and a discussion of the advantages of two-photon absorption. 2PFM imaging was utilized in Chapters 2 to 4 for various applications. In Chapter 2, a new squaraine dye is introduced and its linear and nonlinear photophysical properties are characterized. This compound has very high two-photon absorption (2PA) cross sections and high photostability both in an organic solvent and when encapsulated in micelles. Based on these properties, this dye was demonstrated as a near-infrared (NIR) probe in in vitro 2PFM imaging with excitation over 800 nm wavelength. In Chapter 3, new profluorescent nitroxides are introduced. Nitroxide radicals are utilized for electron paramagnetic resonance (EPR) spectroscopy and in biological systems as some are known, in some manner, to mimic the behavior of superoxide dismutase (SOD) that detoxifies or mitigates oxidative stress by trapping free radicals. Here, two profluorescent nitroxides investigated for use as a two-photon fluorescent oxidative stress indicator in in vitro two-photon fluorescence microscopy (2PFM) imaging. In Chapter 4, two-photon excited (2PE) fluorescence of a conjugated polyelectrolyte (CPE), PPESO3, was studied in methanol and in water. The results of CPE quenching studies were comparable under both one-photon excitation conditions and two-photon excitation. CPE coated silica nanoparticles were incubated in HeLa cells and 2PFM imaging was demonstrated for this new class of fluorescent probe. Supramolecular structures based on organized assemblies/aggregation of chromophores have attracted widespread interest as molecular devices with potential applications in molecular electronics, artificial light harvesting, and pharmacology. In Chapter 5, J-aggregate formation was investigated for two porphyrin-based dyes, 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS, 4) and an amino tris-sulfonate analog (5) in water via UV-vis, fluorescence, and lifetime decay studies. The effect of aggregation on two-photon absorption properties was also investigated. A functionalized norbornene-based homopolymer, synthesized by the ring opening metathesis polymerization technique was used as a J-aggregation enhancement template and had a role of polymer-templating to facilitate porphyrin aggregation and modulate 2PA. In Chapter 6, squaraine dye aggregates templated with single wall carbon nanotubes (SWCNTs) that were atomically clean were studied by using optical absorption spectroscopy, atomic force microscopy (AFM), and photoconductivity measurements. SWCNTs selectively promote the formation of squaraine dye aggregates with a head-to-head stacking arrangement, and these dye aggregates effectively photosensitize SWCNTs, demonstrating that this novel approach can yield highly photosensitized devices.
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Date Issued: 2011
Identifier: CFE0003978, ucf:48665
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003978

Title: Learning Hierarchical Representations for Video Analysis Using Deep Learning.
Creator: Yang, Yang, Shah, Mubarak, Sukthankar, Gita, Da Vitoria Lobo, Niels, Stanley, Kenneth, Sukthankar, Rahul, University of Central Florida
Abstract / Description: With the exponential growth of the digital data, video content analysis (e.g., action, event recognition) has been drawing increasing attention from computer vision researchers. Effective modeling of the objects, scenes, and motions is critical for visual understanding. Recently there has been a growing interest in the bio-inspired deep learning models, which has shown impressive results in speech and object recognition. The deep learning models are formed by the composition of multiple non...
Show moreWith the exponential growth of the digital data, video content analysis (e.g., action, event recognition) has been drawing increasing attention from computer vision researchers. Effective modeling of the objects, scenes, and motions is critical for visual understanding. Recently there has been a growing interest in the bio-inspired deep learning models, which has shown impressive results in speech and object recognition. The deep learning models are formed by the composition of multiple non-linear transformations of the data, with the goal of yielding more abstract and ultimately more useful representations. The advantages of the deep models are three fold: 1) They learn the features directly from the raw signal in contrast to the hand-designed features. 2) The learning can be unsupervised, which is suitable for large data where labeling all the data is expensive and unpractical. 3) They learn a hierarchy of features one level at a time and the layerwise stacking of feature extraction, this often yields better representations.However, not many deep learning models have been proposed to solve the problems in video analysis, especially videos ``in a wild''. Most of them are either dealing with simple datasets, or limited to the low-level local spatial-temporal feature descriptors for action recognition. Moreover, as the learning algorithms are unsupervised, the learned features preserve generative properties rather than the discriminative ones which are more favorable in the classification tasks. In this context, the thesis makes two major contributions.First, we propose several formulations and extensions of deep learning methods which learn hierarchical representations for three challenging video analysis tasks, including complex event recognition, object detection in videos and measuring action similarity. The proposed methods are extensively demonstrated for each work on the state-of-the-art challenging datasets. Besides learning the low-level local features, higher level representations are further designed to be learned in the context of applications. The data-driven concept representations and sparse representation of the events are learned for complex event recognition; the representations for object body parts and structures are learned for object detection in videos; and the relational motion features and similarity metrics between video pairs are learned simultaneously for action verification.Second, in order to learn discriminative and compact features, we propose a new feature learning method using a deep neural network based on auto encoders. It differs from the existing unsupervised feature learning methods in two ways: first it optimizes both discriminative and generative properties of the features simultaneously, which gives our features a better discriminative ability. Second, our learned features are more compact, while the unsupervised feature learning methods usually learn a redundant set of over-complete features. Extensive experiments with quantitative and qualitative results on the tasks of human detection and action verification demonstrate the superiority of our proposed models.
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Date Issued: 2013
Identifier: CFE0004964, ucf:49593
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004964

Title: Complex-valued adaptive digital signal enhancement for applications in wireless communication systems.
Creator: Liu, Ying, Mikhael, Wasfy, Batarseh, Issa, Yang, Thomas, Hunter, Matthew, Haralambous, Michael, Myers, Brent, University of Central Florida
Abstract / Description: In recent decades, the wireless communication industry has attracted a great deal of research efforts to satisfy rigorous performance requirements and preserve high spectral efficiency. Along with this trend, I/Q modulation is frequently applied in modern wireless communications to develop high performance and high data rate systems. This has necessitated the need for applying efficient complex-valued signal processing techniques to highly-integrated, multi-standard receiver devices.In this...
Show moreIn recent decades, the wireless communication industry has attracted a great deal of research efforts to satisfy rigorous performance requirements and preserve high spectral efficiency. Along with this trend, I/Q modulation is frequently applied in modern wireless communications to develop high performance and high data rate systems. This has necessitated the need for applying efficient complex-valued signal processing techniques to highly-integrated, multi-standard receiver devices.In this dissertation, novel techniques for complex-valued digital signal enhancement are presented and analyzed for various applications in wireless communications. The first technique is a unified block processing approach to generate the complex-valued conjugate gradient Least Mean Square (LMS) techniques with optimal adaptations. The proposed algorithms exploit the concept of the complex conjugate gradients to find the orthogonal directions for updating the adaptive filter coefficients at each iteration. Along each orthogonal direction, the presented algorithms employ the complex Taylor series expansion to calculate time-varying convergence factors tailored for the adaptive filter coefficients. The performance of the developed technique is tested in the applications of channel estimation, channel equalization, and adaptive array beamforming. Comparing with the state of the art methods, the proposed techniques demonstrate improved performance and exhibit desirable characteristics for practical use.The second complex-valued signal processing technique is a novel Optimal Block Adaptive algorithm based on Circularity, OBA-C. The proposed OBA-C method compensates for a complex imbalanced signal by restoring its circularity. In addition, by utilizing the complex Taylor series expansion, the OBA-C method optimally updates the adaptive filter coefficients at each iteration. This algorithm can be applied to mitigate the frequency-dependent I/Q mismatch effects in analog front-end. Simulation results indicate that comparing with the existing methods, OBA-C exhibits superior convergence speed while maintaining excellent accuracy. The third technique is regarding interference rejection in communication systems. The research on both LMS and Independent Component Analysis (ICA) based techniques continues to receive significant attention in the area of interference cancellation. The performance of the LMS and ICA based approaches is studied for signals with different probabilistic distributions. Our research indicates that the ICA-based approach works better for super-Gaussian signals, while the LMS-based method is preferable for sub-Gaussian signals. Therefore, an appropriate choice of interference suppression algorithms can be made to satisfy the ever-increasing demand for better performance in modern receiver design.
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Date Issued: 2012
Identifier: CFE0004572, ucf:49192
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004572

Title: Power Effects on Consumer Well-Being: Two Essays on The Power Effects on Donation and Material/Experiential Consumption.
Creator: Liu, Yue, He, Xin, Tafaghodijami, Ata, Massiah, Carolyn, Yang, Xiaojing, Mao, Huifang, University of Central Florida
Abstract / Description: Power is a fundamental concept in social science (Russell 1938), which has gained much academic attention in various disciplines. Two essays of this dissertation examine the theoretical and practical implications of power effects on donation decisions and material/experiential consumption.The first essay demonstrates power's moderating effect on the relationship between publicity and donation. Specifically, it is proposed that powerful people tend to donate more in public (vs. private)...
Show morePower is a fundamental concept in social science (Russell 1938), which has gained much academic attention in various disciplines. Two essays of this dissertation examine the theoretical and practical implications of power effects on donation decisions and material/experiential consumption.The first essay demonstrates power's moderating effect on the relationship between publicity and donation. Specifically, it is proposed that powerful people tend to donate more in public (vs. private) situation, whereas powerless people do not show such a difference. This effect is driven by people's concern about self-presentation in a donation scenario. Additionally, this effect only holds when people strongly believe that high donation enhances others' positive impression of them, but dilutes when such belief is not held. The theorizing is supported across four studies.The second essay focuses on how power influences consumers' preferences for material and experiential products. It is predicted that those who feel powerless tend to spend more of their discretionary money on material products than experiential products. This effect occurs through feelings of resourcefulness caused by possessing material or experiential goods. In addition, this effect is further moderated by implicit theory, such that the impact of power on material versus experience product choice persists for incremental theorists but dissipates for entity theorists. Three experiments provide support to this proposition.Overall, by investigating how power influences people's donation behavior and choice of material/experiential products, this dissertation strengthens the understanding of power's effectson consumer behavior and provides practical implications on how power status can influence consumers' well-being.
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Date Issued: 2017
Identifier: CFE0006894, ucf:51710
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006894

Title: Exploring FPGA Implementation for Binarized Neural Network Inference.
Creator: Yang, Li, Fan, Deliang, Zhang, Wei, Lin, Mingjie, University of Central Florida
Abstract / Description: Deep convolutional neural network has taken an important role in machine learning algorithm. It is widely used in different areas such as computer vision, robotics, and biology. However, the models of deep neural networks become larger and more computation complexity which is a big obstacle for such huge model to implement on embedded systems. Recent works have shown the binarized neural networks (BNN), utilizing binarized (i.e. +1 and -1) convolution kernel and binarized activation function,...
Show moreDeep convolutional neural network has taken an important role in machine learning algorithm. It is widely used in different areas such as computer vision, robotics, and biology. However, the models of deep neural networks become larger and more computation complexity which is a big obstacle for such huge model to implement on embedded systems. Recent works have shown the binarized neural networks (BNN), utilizing binarized (i.e. +1 and -1) convolution kernel and binarized activation function, can significantly reduce the parameter size and computation cost, which makes it hardware-friendly for Field-Programmable Gate Arrays (FPGAs) implementation with efficient energy cost. This thesis proposes to implement a new parallel convolutional binarized neural network (i.e. PC-BNN) on FPGA with accurate inference. The embedded PC-BNN is designed for image classification on CIFAR-10 dataset and explores the hardware architecture and optimization of customized CNN topology.The parallel-convolution binarized neural network has two parallel binarized convolution layers which replaces the original single binarized convolution layer. It achieves around 86% on CIFAR-10 dataset and owns 2.3Mb parameter size. We implement our PC-BNN inference into the Xilinx PYNQ Z1 FPGA board which only has 4.9Mb on-chip Block RAM. Since the ultra-small network parameter, the whole model parameters can be stored on on-chip memory which can greatly reduce energy consumption and computation latency. Meanwhile, we design a new pipeline streaming architecture for PC-BNN hardware inference which can further increase the performance. The experiment results show that our PC-BNN inference on FPGA achieves 930 frames per second and 387.5 FPS/Watt, which are among the best throughput and energy efficiency compared to most recent works.
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Date Issued: 2018
Identifier: CFE0007384, ucf:52067
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007384

Title: A Comprehensive Assessment of Vehicle-to-Grid Systems and Their Impact to the Sustainability of Current Energy and Water Nexus.
Creator: Zhao, Yang, Tatari, Omer, Oloufa, Amr, Mayo, Talea, Zheng, Qipeng, University of Central Florida
Abstract / Description: This dissertation aims to explore the feasibility of incorporating electric vehicles into the electric power grid and develop a comprehensive assessment framework to predict and evaluate the life cycle environmental, economic and social impact of the integration of Vehicle-to-Grid systems and the transportation-water-energy nexus. Based on the fact that electric vehicles of different classes have been widely adopted by both fleet operators and individual car owners, the following questions...
Show moreThis dissertation aims to explore the feasibility of incorporating electric vehicles into the electric power grid and develop a comprehensive assessment framework to predict and evaluate the life cycle environmental, economic and social impact of the integration of Vehicle-to-Grid systems and the transportation-water-energy nexus. Based on the fact that electric vehicles of different classes have been widely adopted by both fleet operators and individual car owners, the following questions are investigated: 1. Will the life cycle environmental impacts due to vehicle operation be reduced? 2. Will the implementation of Vehicle-to-Grid systems bring environmental and economic benefits? 3. Will there be any form of air emission impact if large amounts of electric vehicles are adopted in a short time? 4. What is the role of the Vehicle-to-Grid system in the transportation-water-energy nexus? To answer these questions: First, the life cycle environmental impacts of medium-duty trucks in commercial delivery fleets are analyzed. Second, the operation mechanism of Vehicle-to-Grid technologies in association with charging and discharging of electric vehicles is researched. Third, the feasible Vehicle-to-Grid system is further studied taking into consideration the spatial and temporal variance as well as other uncertainties within the system. Then, a comparison of greenhouse gas emission mitigation of the Vehicle-to-Grid system and the additional emissions caused by electric vehicle charging through marginal electricity is analyzed. Finally, the impact of the Vehicle-to-Grid system in the transportation-water-energy nexus, and the underlying environmental, economic and social relationships are simulated through system dynamic modeling. The results provide holistic evaluations and spatial and temporal projections of electric vehicles, Vehicle-to-Grid systems, wind power integration, and the transportation-water-energy nexus.
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Date Issued: 2017
Identifier: CFE0007300, ucf:52153
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007300

Title: Towards Scalable Nanomanufacturing: Modeling the Interaction of Charged Droplets from Electrospray using GPU.
Creator: Yang, Weiwei, Deng, Weiwei, Chen, Ruey-Hung, Ilie, Marcel, University of Central Florida
Abstract / Description: Electrospray is an atomization method subject to intense study recently due to its monodispersity and the wide size range of droplets it can produce, from nanometers to hundreds of micrometers. This thesis focuses on the numerical and theoretical modeling of the interaction of charged droplets from the single and multiplexed electrospray. We studied two typical scenarios: large area film depositions using multiplexed electrospray and fine pattern printings assisted by linear electrostatic...
Show moreElectrospray is an atomization method subject to intense study recently due to its monodispersity and the wide size range of droplets it can produce, from nanometers to hundreds of micrometers. This thesis focuses on the numerical and theoretical modeling of the interaction of charged droplets from the single and multiplexed electrospray. We studied two typical scenarios: large area film depositions using multiplexed electrospray and fine pattern printings assisted by linear electrostatic quadrupole focusing. Due to the high computation power requirement in the unsteady n-body problem, graphical processing unit (GPU) which delivers 10 Tera flops in computation power is used to dramatically speed up the numerical simulation both efficiently and with low cost. For large area film deposition, both the spray profile and deposition number density are studied for different arrangements of electrospray and electrodes. Multiplexed electrospray with hexagonal nozzle configuration can not give us uniform deposition though it has the highest packing density. Uniform film deposition with variation (<) 5% in thickness was observed with the linear nozzle configuration combined with relative motion between ES source and deposition substrate. For fine pattern printing, linear quadrupole is used to focus the droplets in the radial direction while maintaining a constant driving field at the axial direction. Simulation shows that the linear quadrupole can focus the droplets to a resolution of a few nanometers quickly when the inter-droplet separation is larger than a certain value. Resolution began to deteriorate drastically when the inter-droplet separation is smaller than that value. This study will shed light on using electrospray as a scalable nanomanufacturing approach.
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Date Issued: 2012
Identifier: CFE0004463, ucf:49333
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004463

Title: Electrical Parasitic Bandwidth Limitations of Oxide-Free Lithographic Vertical-Cavity Surface-Emitting Lasers.
Creator: Yang, Xu, Deppe, Dennis, Fathpour, Sasan, Wu, Shintson, Gong, Xun, University of Central Florida
Abstract / Description: Nowadays, Vertical-Cavity Surface-Emitting Lasers (VCSELs) are the most popular optical sources in short-reach data communications. In the commercial oxide VCSEL technology, an oxide aperture is created inside resonant cavity in realizing good mode and current confinement, however, high electrical resistance comes along with forming the oxide aperture and the electrical parasitic bandwidth becomes the main limitation in modulation speed. In this report, electrical bandwidths of oxide-free...
Show moreNowadays, Vertical-Cavity Surface-Emitting Lasers (VCSELs) are the most popular optical sources in short-reach data communications. In the commercial oxide VCSEL technology, an oxide aperture is created inside resonant cavity in realizing good mode and current confinement, however, high electrical resistance comes along with forming the oxide aperture and the electrical parasitic bandwidth becomes the main limitation in modulation speed. In this report, electrical bandwidths of oxide-free lithographic VCSELs have been studied along with their general lasing properties. Due to the new ways of fabricating the aperture, record low resistances have been achieved in oxide-free lithographic VCSELs with various sizes, while high slope efficiencies and high output powers have been maintained. High speed simulation has been performed showing the very low differential resistances will benefit much to the electrical parasitic bandwidths, and are expected to produce higher modulation speed. A bottom emitting structure has been proposed and analyzed, showing reduction in both mirror resistance and capacitance will further improve the modulation speed. The total 3-dB modulation bandwidth is expected to be 50-80 GHz, much higher than the bandwidth reached in existing oxide VCSELs. Lithographic VCSELs also show superior lasing characteristics, including record low thermal resistance and record high output power. The maximum power exceeds 19 mW in a 6 (&)#181;m device and over 50 % power conversion efficiency has been achieved. A maximum single mode operation power of 5 mW has been observed from a 1 (&)#181;m diameter VCSEL. High temperature stress testing has been performed showing lithographic VCSELs can operate more reliably than oxide VCSELs under extreme operating conditions. Lithographic VCSEL with low electrical resistance, single-mode operation, high efficiency, and high power will be a strong candidate as the optical source in high speed data communications, as well as other applications such as high power VCSEL arrays and optical sensing.
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Date Issued: 2016
Identifier: CFE0006425, ucf:51491
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006425

deep learning (2)	+ -
electrospray (2)	+ -
Buckypaper (1)	+ -
Ceramic Thin Film (1)	+ -
Chirality (1)	+ -

Collaborative tool (1)	+ -
Collision Avoidance (1)	+ -
Corporate Governance (1)	+ -
Crohn's Disease (1)	+ -
Diblock Copolymer (1)	+ -
Diversity Reception (1)	+ -
Donation (1)	+ -
Dynamic Channel Environment (1)	+ -
ENHANS (1)	+ -
Electric Vehicles (1)	+ -
FPGA (1)	+ -
GPU simulation (1)	+ -
HHG (1)	+ -
Hierarchical Mesopores (1)	+ -
Hollow Nanospheres (1)	+ -
ICA (1)	+ -
Integrated circuit design (1)	+ -
Interference Suppression (1)	+ -
LDPC (1)	+ -
Material/Experiential Consumption (1)	+ -
Non-oxide Ceramics (1)	+ -
Nonholonomic (1)	+ -
OFDM (1)	+ -
PDC (1)	+ -
PSiP (1)	+ -

University of Central Florida (26)	+ -
Yang, Yang (4)	+ -
Wu, Shintson (3)	+ -
Zhai, Lei (3)	+ -
Chen, Ruey-Hung (2)	+ -

Deng, Weiwei (2)	+ -
Dong, Yajie (2)	+ -
Fang, Jiyu (2)	+ -
Ilie, Marcel (2)	+ -
Mikhael, Wasfy (2)	+ -
Wu, Xinzhang (2)	+ -
Yang, Weiwei (2)	+ -
Ahn, Hyo-Yang (1)	+ -
An, Linan (1)	+ -
Batarseh, Issa (1)	+ -
Belfield, Kevin (1)	+ -
Chang, Zenghu (1)	+ -
Chen, Quanfang (1)	+ -
Coffey, Kevin (1)	+ -
Da Vitoria Lobo, Niels (1)	+ -
Deppe, Dennis (1)	+ -
Fan, Deliang (1)	+ -
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Feng, Xiaofeng (1)	+ -
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Gong, Xun (1)	+ -
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