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Electrical and Computer Engineering
Department of Electrical and Computer Engineering: Faculty Publications
- Keyword
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- Adaptive resampling (1)
- Condition monitoring (1)
- Current (1)
- Effective capacity (1)
- Energy efficiency (1)
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- Energy per information bit (1)
- Fault diagnosis (1)
- Gearbox (1)
- Low-power regime (1)
- Multiple-access fading channels (1)
- Permanent magnet (PM) generator (1)
- Quality of service (1)
- Superposition coding (1)
- Time-division multiple access (1)
- Tooth break (1)
- Wideband regime (1)
- Wideband slope. (1)
- Wind turbine (WT) (1)
Articles 1 - 15 of 15
Full-Text Articles in Computer Engineering
Online State Of Charge And Electrical Impedance Estimation For Multicell Lithium-Ion Batteries, Taesic Kim, Wei Qiao, Liyan Qu
Online State Of Charge And Electrical Impedance Estimation For Multicell Lithium-Ion Batteries, Taesic Kim, Wei Qiao, Liyan Qu
Department of Electrical and Computer Engineering: Faculty Publications
This paper proposes a hybrid battery model-based high-fidelity state of charge (SOC) and electrical impedance estimation method for multicell lithium-ion batteries. The hybrid battery model consists of an enhanced Coulomb counting algorithm for SOC estimation and an electrical circuit battery model. A particle swarm optimization (PSO)-based online parameter identification algorithm is designed to estimate the electrical parameters of the cells sequentially. An SOC compensator is designed to correct the errors of the enhanced Coulomb counting SOC estimations for the cells sequentially. This leads to an accurate, robust online SOC estimation for individual cells of a battery pack. The proposed method …
Subwavelength Ripples Adjustment Based On Electron Dynamics Control By Using Shaped Ultrafast Laser Pulse Trains, Lan Jiang, Xuesong Shi, Xin Li, Yanping Yuan, Cong Wang, Yongfeng Lu
Subwavelength Ripples Adjustment Based On Electron Dynamics Control By Using Shaped Ultrafast Laser Pulse Trains, Lan Jiang, Xuesong Shi, Xin Li, Yanping Yuan, Cong Wang, Yongfeng Lu
Department of Electrical and Computer Engineering: Faculty Publications
This study reveals that the periods, ablation areas and orientations of periodic surface structures (ripples) in fused silica can be adjusted by using designed femtosecond (fs) laser pulse trains to control transient localized electron dynamics and corresponding material properties. By increasing the pulse delays from 0 to 100fs, the ripple periods are changed from ~550nm to ~255nm and the orientation is rotated by 90°. The nearwavelength/subwavelength ripple periods are close to the fundamental/second-harmonic wavelengths in fused silica respectively. The subsequent subpulse of the train significantly impacts free electron distributions generated by the previous subpulse(s), which might influence the formation mechanism …
Remote Chemical And Elemental Analyss By Ultra Fast Spectroscopy, Dennis R. Alexander
Remote Chemical And Elemental Analyss By Ultra Fast Spectroscopy, Dennis R. Alexander
Department of Electrical and Computer Engineering: Faculty Publications
Systems and methods are provided for monitoring materials using ultra fast laser pulses. Ultra fast laser pulses, such as femtosecond or attosecond laser pulses, are applied to the materials and laser pulses that result from interactions between the ultra fast laser pulses and the materials are collected. Spectral content of the resulting pulses is generated and presented. The elemental composition of the materials is determined using the spectral content.
Sample Investigating System And Method Of Use, Martin M. Liphardt, Thomas E. Tiwald, Blaine D. Johs, Jeffery S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, Ronald A. Synowicki, John A. Woollam
Sample Investigating System And Method Of Use, Martin M. Liphardt, Thomas E. Tiwald, Blaine D. Johs, Jeffery S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, Ronald A. Synowicki, John A. Woollam
Department of Electrical and Computer Engineering: Faculty Publications
A spectroscopic system for adjusting spacing between an adjacent source/detector as a unit, and a sample, and a reflecting means for directing an incident beam which reflects from said sample back onto said sample and then into the detector along a locus which is in a plane of incidence that is offset from that of the incident beam, or directly from the reflecting means into the detector, including means for reducing reflections of a beam of electromagnetic from the back of a sample, including methodology of use.
Sample Investigating Systemand Method Of Use, Martin M. Liphardt, Thomas E. Tiwald, Blaine D. Johs, Jeffrey S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, Ronald A. Synowicki, John A. Woollam
Sample Investigating Systemand Method Of Use, Martin M. Liphardt, Thomas E. Tiwald, Blaine D. Johs, Jeffrey S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, Ronald A. Synowicki, John A. Woollam
Department of Electrical and Computer Engineering: Faculty Publications
A spectroscopic system for adjusting spacing between an adjacent source/detector as a unit, and a sample, and a reflecting means for directing an incident beam which reflects from said sample back onto said sample and then into the detector along a locus which is in a plane of incidence that is offset from that of the incident beam, or directly from the reflecting means into the detector, including means for reducing reflections of a beam of electromagnetic from the back of a sample, including methodology of use.
Optimally Enhanced Optical Emission In Laser-Induced Breakdown Spectroscopy By Combining Spatial Confinement And Dual-Pulse Irradiation, L. B. Guo, B. Y. Zhang, X. N. He, C. M. Li, Y. S. Zhou, T. Wu, J. B. Park, X. Y. Zeng, Yongfeng Lu
Optimally Enhanced Optical Emission In Laser-Induced Breakdown Spectroscopy By Combining Spatial Confinement And Dual-Pulse Irradiation, L. B. Guo, B. Y. Zhang, X. N. He, C. M. Li, Y. S. Zhou, T. Wu, J. B. Park, X. Y. Zeng, Yongfeng Lu
Department of Electrical and Computer Engineering: Faculty Publications
In laser-induced breakdown spectroscopy (LIBS), a pair of aluminum-plate walls were used to spatially confine the plasmas produced in air by a first laser pulse (KrF excimer laser) from chromium (Cr) targets with a second laser pulse (Nd:YAG laser at 532 nm, 360 mJ/pulse) introduced parallel to the sample surface to re-excite the plasmas. Optical emission enhancement was achieved by combing the spatial confinement and dual-pulse LIBS (DP-LIBS), and then optimized by adjusting the distance between the two walls and the interpulse delay time between both laser pulses. A significant enhancement factor of 168.6 for the emission intensity of the …
A Low-Cost, Reliable, High-Throughput System For Rodent Behavioral Phenotyping In A Home Cage Environment, Steven A. Parkison, Jay D. Carlson, Tammy R. Chaudoin, Traci A. Hoke, A. Katrin Schenk, Evan H. Goulding, Lance C. Pérez, Stephen J. Bonasera
A Low-Cost, Reliable, High-Throughput System For Rodent Behavioral Phenotyping In A Home Cage Environment, Steven A. Parkison, Jay D. Carlson, Tammy R. Chaudoin, Traci A. Hoke, A. Katrin Schenk, Evan H. Goulding, Lance C. Pérez, Stephen J. Bonasera
Department of Electrical and Computer Engineering: Faculty Publications
Inexpensive, high-throughput, low maintenance systems for precise temporal and spatial measurement of mouse home cage behavior (including movement, feeding, and drinking) are required to evaluate products from large scale pharmaceutical design and genetic lesion programs. These measurements are also required to interpret results from more focused behavioral assays. We describe the design and validation of a highly-scalable, reliable mouse home cage behavioral monitoring system modeled on a previously described, one-ofa- kind system [1]. Mouse position was determined by solving static equilibrium equations describing the force and torques acting on the system strain gauges; feeding events were detected by a photobeam …
Current-Based Diagnosis For Gear Tooth Breaks In Wind Turbine Gearboxes, Dingguo Lu, Xiang Gong, Wei Qiao
Current-Based Diagnosis For Gear Tooth Breaks In Wind Turbine Gearboxes, Dingguo Lu, Xiang Gong, Wei Qiao
Department of Electrical and Computer Engineering: Faculty Publications
Gearbox faults constitute a significant portion of all faults and downtime in wind turbines (WTs). Current-based gearbox fault diagnosis has significant advantages over traditional vibration-based techniques in terms of cost, implementation, and reliability. This paper derives a mathematical model for a WT drive train consisting of a twostage gearbox and a permanent magnet (PM) generator, from which the characteristic frequencies of gear tooth breaks in generator stator current frequency spectra are clearly identified. A adaptive signal resampling algorithm is proposed to convert the variable fault characteristic frequencies to constant values for WTs running at variable speeds. A fault detector is …
Energy Efficiency In Multiaccess Fading Channels Under Qos Constraints, Deli Qiao, Mustafa Cenk Gursoy, Senem Velipasalar
Energy Efficiency In Multiaccess Fading Channels Under Qos Constraints, Deli Qiao, Mustafa Cenk Gursoy, Senem Velipasalar
Department of Electrical and Computer Engineering: Faculty Publications
In this article, transmission over multiaccess fading channels under quality-of-service (QoS) constraints is studied in the low-power and wideband regimes. QoS constraints are imposed as limitations on the buffer violation probability. The effective capacity, which characterizes the maximum constant arrival rates in the presence of such statistical QoS constraints, is employed as the performance metric. A two-user multiaccess channel model is considered, and the minimum bit energy levels and wideband slope regions are characterized for different transmission and reception strategies, namely time-division multiple-access (TDMA), superposition coding with fixed decoding order, and superposition coding with variable decoding order. It is shown …
Nonlinear Plasmonic Cloaks To Realize Giant All-Optical Scattering Switching, Christos Argyropoulos, Pai-Yen Chen, Francesco Monticone, Giuseppe D'Aguanno, Andrea Alu
Nonlinear Plasmonic Cloaks To Realize Giant All-Optical Scattering Switching, Christos Argyropoulos, Pai-Yen Chen, Francesco Monticone, Giuseppe D'Aguanno, Andrea Alu
Department of Electrical and Computer Engineering: Faculty Publications
Here we extend the reach of Fano resonant coupling by combining this concept with cloaking and plasmonic resonances in a single nonlinear nanoparticle, in order to realize giant all-optical scattering nanoswitches controlled by moderate pumping intensities. We show that a core-shell nonlinear plasmonic particle may be designed to abruptly switch from being completely cloaked to being strongly resonant, with up to a 40 dB cross-sectional difference. Self-tunable optical cloaks and resonant scatterers are envisioned for use as efficient all-optical switches and nanomemories.
Matching And Funneling Light At The Plasmonic Brewster Angle, Christos Argyropoulos, Giuseppe D'Aguanno, Nadia Mattiucci, Neset Akozbek, Mark J. Bloemer, Andrea Alu
Matching And Funneling Light At The Plasmonic Brewster Angle, Christos Argyropoulos, Giuseppe D'Aguanno, Nadia Mattiucci, Neset Akozbek, Mark J. Bloemer, Andrea Alu
Department of Electrical and Computer Engineering: Faculty Publications
The ultrabroadband impedance matching of metallic gratings at the plasmonic Brewster angle [A. Al`u et al., Phys. Rev. Lett. 106, 123902 (2011)] is analyzed here in several realistic scenarios and configurations, and in the case of nonmonochromatic excitation. This phenomenon is the analogy of the well-known Brewster transmission for dielectric slabs but, when applied to plasmonic gratings, has the remarkable property of funneling and concentrating light within subwavelength slits. We analyze here how the presence of absorption and of realistic substrates and/or superstrates may influence the phenomenon, its beamwidth and angular selectivity, and its overall performance in the case …
Boosting Optical Nonlinearities In E-Near-Zero Plasmonic Channels, Christos Argyropoulos, Pai-Yen Chen, Giuseppe D'Aguanno, Nadar Engheta, Andrea Alu
Boosting Optical Nonlinearities In E-Near-Zero Plasmonic Channels, Christos Argyropoulos, Pai-Yen Chen, Giuseppe D'Aguanno, Nadar Engheta, Andrea Alu
Department of Electrical and Computer Engineering: Faculty Publications
The anomalous transmission properties of zero-permittivity ultranarrow channels are used to boost Kerr nonlinearities and achieve switching and bistable response for moderate optical intensities. Strong field enhancement, uniform all along the channel, is a typical feature of ε-near-zero supercoupling and is shown to be particularly suited to enhance nonlinear effects. This is obtained by designing narrow apertures at cutoff in a plasmonic screen. We show that this nonlinear mechanism can significantly outperform nonlinearities in traditional Fabry-P´erot resonant gratings.
Broadband Brewster Transmission Through 2d Metallic Gratings, Khai Q. Le, Christos Argyropoulos, Nadia Mattiucci, Giuseppe D'Aguanno, Mark J. Bloemer, Andrea Alu
Broadband Brewster Transmission Through 2d Metallic Gratings, Khai Q. Le, Christos Argyropoulos, Nadia Mattiucci, Giuseppe D'Aguanno, Mark J. Bloemer, Andrea Alu
Department of Electrical and Computer Engineering: Faculty Publications
Recently, we have introduced a mechanism to achieve ultrabroadband light funnelling and total transmission through 1D narrow metallic gratings at a specific incidence angle, the so-called plasmonic Brewster angle. This phenomenon is based on impedance matching between the guided modes supported by ultranarrow linear slits and transverse-magnetic waves at oblique incidence. In this paper, we demonstrate that such phenomenon, representing the equivalent of Brewster transmission for plasmonic screens, can also occur in 2D metallic gratings of various structural forms and shapes, and that it may be made insensitive to the azimuthal, or polarization, angle u. This finding may have relevant …
Laser Induced Breakdown Spectroscopy Having Enhanced Signal-To-Noise Ratio, Dennis R. Alexander, Troy Anderson, John C. Bruce Iii
Laser Induced Breakdown Spectroscopy Having Enhanced Signal-To-Noise Ratio, Dennis R. Alexander, Troy Anderson, John C. Bruce Iii
Department of Electrical and Computer Engineering: Faculty Publications
A material can be analyzed using short pulses by applying a first pulse and a second pulse to the material in which the second pulse is delayed relative to the first pulse. The first and second pulses are directed toward a material along collinear paths, and the material is ablated using the first pulse to cause particles to be emitted from the surface of the material. The emitted particles are atomized and/or ionized using the second pulse, and the radiation from the atomized and/or ionized particles is analyzed.
Empirical Correction For Spectroscopic Ellipsometric Measurements Of Rough Or Textured Surfaces, Craig M. Herzinger, Blaine D. Johs, Mathias M. Schubert, Tino Hofmann
Empirical Correction For Spectroscopic Ellipsometric Measurements Of Rough Or Textured Surfaces, Craig M. Herzinger, Blaine D. Johs, Mathias M. Schubert, Tino Hofmann
Department of Electrical and Computer Engineering: Faculty Publications
A method of applying spectroscopic ellipsometry to arrive at accurate values of optical and physical properties for thin films on samples having rough or textured surfaces.