Open Access. Powered by Scholars. Published by Universities.®
Electrical and Computer Engineering
Electrical and Computer Engineering Faculty Research & Creative Works
- Keyword
-
- Feature extraction (2)
- IC packaging (2)
- Machine learning (2)
- Mobile Ad Hoc Networks (2)
- Mobile Computing (2)
-
- Mobile Wireless Network (2)
- Ns-3 Simulation (2)
- Resilience (2)
- Survivability (2)
- Telecommunication Networks (2)
- Trace radiation (2)
- Via radiation (2)
- A-center (1)
- Aharonov-Bohm ring (1)
- Aircraft Radome (1)
- Alternative augmented electric field integral equation-electric field integral equation process (1)
- And Complex Permittivity Estimation (1)
- Anti-bonding state (1)
- Asymptotic waveform evaluation (AWE) (1)
- Augmented electric field integral equation (1)
- Binary Particle Swarm Optimization (BPSO) (1)
- Biomedical journal (1)
- Bonding state (1)
- Boundary integral equation (BIE) (1)
- Broadband (1)
- Cavity modes (1)
- Ceramics (1)
- Chromaticity (1)
- Classification accuracy (1)
- Clinical decision support (1)
Articles 1 - 30 of 43
Full-Text Articles in Engineering
Analytical Representations For Frequency Dependences Of Microwave Permeability, Konstantin N. Rozanov, Marina Koledintseva
Analytical Representations For Frequency Dependences Of Microwave Permeability, Konstantin N. Rozanov, Marina Koledintseva
Electrical and Computer Engineering Faculty Research & Creative Works
Electromagnetic materials applied to solve various EMC and EMI problems require adequate analytical description of their RF and microwave material parameters. This is necessary for numerical optimization of wideband electromagnetic performance of devices incorporating these materials. The paper discusses the shape of frequency dependences of microwave permeability in homogeneous materials and composites. The Lorentzian frequency dispersion law is shown to allow for rather accurate description of all types of magnetic loss peaks, including those related to the ferromagnetic resonance and the effect of eddy currents. To model wideband electromagnetic performance of composites, mixing laws are typically used. The problem is …
Alternative Aefie-Efie Method For Broadband Cem Modeling, Jia Liu, Li (Lijun) Jun Jiang
Alternative Aefie-Efie Method For Broadband Cem Modeling, Jia Liu, Li (Lijun) Jun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
It is well known that the electric field integral equation (EFIE) has the low frequency breakdown problem while the Augmented electric field integral equation (AEFIE) method has the high frequency breakdown issue. To obtain a unified method that works for both low and high frequencies without manual switching of methods, a novel and simple method is proposed in this paper. It uses AEFIE and EFIE to compensate each other iteratively in all frequency regimes to guarantee the accuracy of the solution. As a result, it effectively extends AEFIE to the high frequency regime and extends EFIE to the low frequency …
Electromagnetic Properties Of Metal Granular Composite Materials For Emc Applications, Takanori Tsutaoka, Aiko Tsurunaga, Teruhiro Kasagi, Kenichi Hatakeyama, Marina Koledintseva
Electromagnetic Properties Of Metal Granular Composite Materials For Emc Applications, Takanori Tsutaoka, Aiko Tsurunaga, Teruhiro Kasagi, Kenichi Hatakeyama, Marina Koledintseva
Electrical and Computer Engineering Faculty Research & Creative Works
Electromagnetic properties of copper and Fe55Ni45alloy (Permalloy) composite materials have been studied by measuring the relative complex permeability (µr = µr’– jµr”), and permittivity (Σr = Σr’– jΣr”) spectra over the microwave range, as well as the a.c. electrical conductivity σac spectra. The variation of σac and Σr with particle content shows the insulator-metal transition due to the percolation effect. The effective cluster model can be applied to the percolation effect in permittivity. The permeability spectra in Permalloy composites, which contain the percolated particles, …
A Single-Layer Compact Hf-Uhf Dual-Band Rfid Tag Antenna, Zi Long Ma, Li (Lijun) Jun Jiang, Jingtian Xi, Terry Tao Ye
A Single-Layer Compact Hf-Uhf Dual-Band Rfid Tag Antenna, Zi Long Ma, Li (Lijun) Jun Jiang, Jingtian Xi, Terry Tao Ye
Electrical and Computer Engineering Faculty Research & Creative Works
This letter presents a novel dual-band (HF and UHF) radio frequency identification (RFID) tag antenna. Two key challenges are faced: the compact dimension and the impaired bandwidth due to the couplings between two band structures. To enable the implementation of whole design on a credit-card-size single-layer support, a spiral coil along the edges of the card is designed to handle the HF (13.56 MHz) near-field coupling, and the UHF antenna is placed inside the coil instead of outside. Meanwhile, a diagonal symmetric design consisting of two meander lines inside the spiral coil is adopted for UHF band. This structure supports …
A Circular Polarization Hybrid-Integrated Rectangular Ring Antenna For Rfid Reader, Yan Li, Sheng Sun, Lijun Jiang, Terry T. Ye
A Circular Polarization Hybrid-Integrated Rectangular Ring Antenna For Rfid Reader, Yan Li, Sheng Sun, Lijun Jiang, Terry T. Ye
Electrical and Computer Engineering Faculty Research & Creative Works
In this paper, a compact hybrid-integrated microstrip rectangular ring antenna with circular polarization is proposed for RFID reader. By integrating a cross-slotted patch hybrid with a rectangular ring antenna in the same plane, the proposed antenna has the features of circular polarization, compact size, low cost, light weight and unique flexibility for RFID applications. A prototype operating at 915 MHz is designed and fabricated. The measured results agree well with the simulated results. © 2012 IEEE.
Integral Equation Method For Analyzing Purcell Effect In Plasmonic System, Yongpin P. Chen, Weng Cho Chew, Wei E.I. Sha, W. C.H. Choy, Lijun Jiang
Integral Equation Method For Analyzing Purcell Effect In Plasmonic System, Yongpin P. Chen, Weng Cho Chew, Wei E.I. Sha, W. C.H. Choy, Lijun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
Integral equation method is applied to analyze the Purcell effect in plasmonic system in this paper. By applying the Fermi's golden rule, the Purcell effect of a quantum emitter can be calculated from the local density of states (LDOS), which can be further expressed by the imaginary part of the Green's function of the whole system. To obtain this Green's function numerically, the layered medium Green's function is utilized to simplify the modeling of planarly layered substrate, where the surface plasmon polaritons (SPPs) can be sustained. The metallic nano scatterers are introduced to excite the localized surface plasmons (LSP), and …
The Far Field Transformation Using The Iterative Srm Based On The Phaseless Data, Ping Li, Li (Lijun) Jun Jiang
The Far Field Transformation Using The Iterative Srm Based On The Phaseless Data, Ping Li, Li (Lijun) Jun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
Conventional equivalent source reconstruction methods (SRM) require both phase and amplitude information of the field data. However, there are situations where the phase information is not easy to obtain. Hence, developing novel SRM based on phaseless data is necessary. In this paper, a novel iterative SRM based on two sets of measured phaseless data is presented. It can reproduce the 3D radiation pattern with very good accuracy. Integral equation (IE) is employed to build reconstruct equivalent source. Combined field IE (CFIE) is also employed to obtain more physical current distribution. © 2012 IEEE.
Characterization Of Wave Physics Using The Rigorous Helmholtz Decomposition Based On The Surface Integral Equation, Xiaoyan Y.Z. Xiong, Wei E.I. Sha, Li (Lijun) Jun Jiang
Characterization Of Wave Physics Using The Rigorous Helmholtz Decomposition Based On The Surface Integral Equation, Xiaoyan Y.Z. Xiong, Wei E.I. Sha, Li (Lijun) Jun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
Helmholtz decomposition (HD) is a fundamental tool of vector calculus and plays an important role in electromagnetics. In this work, arbitrary vector field defined on the open or closed surface is decomposed into the sum of an irrotational (curl-free) vector field and a solenoidal (divergence-free) vector field by using the surface integral equation method. Unlike the popular loop-tree decomposition that is only a quasi-HD suitable for the circuit physics in the low frequency regime, the HD developed in this paper is rigorous and can capture both circuit and wave physics from very low frequency to high frequency regimes. The work …
An Efficient Method For Highly Oscillatory Physical Optics Integrals, Yu Mao Wu, Li (Lijun) Jun Jiang, Weng Cho Chew
An Efficient Method For Highly Oscillatory Physical Optics Integrals, Yu Mao Wu, Li (Lijun) Jun Jiang, Weng Cho Chew
Electrical and Computer Engineering Faculty Research & Creative Works
In this work, we use the steepest descent path (SDP) method in the complex analysis to calculate the highly oscillatory physical optics (PO) integral with quadratic phase and amplitude variations on the triangular patch. Compared with traditional approximate asymptotic expansion approach, our method has significantly improved the PO integral accuracy by one to two digits (10 1 to 102) for evaluating the PO integral. Moreover, the computation effort for the highly oscillatory integral is frequency independent. © 2012 IEEE.
Electromagnetic Emissions From The Ic Packaging, Nick K.H. Huang, Li (Lijun) Jun Jiang, Huichun Yu, Gang Li, Shuai Xu, Tao Wang, Huasheng Ren
Electromagnetic Emissions From The Ic Packaging, Nick K.H. Huang, Li (Lijun) Jun Jiang, Huichun Yu, Gang Li, Shuai Xu, Tao Wang, Huasheng Ren
Electrical and Computer Engineering Faculty Research & Creative Works
The EMC and EMI of the IC packaging are becoming increasingly important to modern electronics. Its EMC, SI, and PI have been broadly attested. But electromagnetic radiations from IC packaging and the corresponding EMI were seldom studied. In this paper, the fundamental principles and properties of the electromagnetic radiations caused by vias and traces in IC packagings are carefully investigated. Various radiation mechanisms are analyzed for different representative scenarios. Numerical simulations are employed to support the analyzing results. © 2012 IEEE.
Fundamental Components Of The Ic Packaging Electromagnetic Interference (Emi) Analysis, Nick K.H. Huang, Li (Lijun) Jun Jiang, Huichun Yu, Gang Li, Shuai Xu, Huasheng Ren
Fundamental Components Of The Ic Packaging Electromagnetic Interference (Emi) Analysis, Nick K.H. Huang, Li (Lijun) Jun Jiang, Huichun Yu, Gang Li, Shuai Xu, Huasheng Ren
Electrical and Computer Engineering Faculty Research & Creative Works
The IC packaging EMC/SI/PI problems have been broadly attested. But IC packaging EMI was seldom addressed. Because the EMI emission by IC packagings is increasingly significant, in this paper, EMI behaviors are systematically studied. To fundamentally understand the radiation mechanism, radiated contributions from ground lids, vias, and traces of the packaging are investigated and modeled separately. It is seen that the packaging EMI has clearly low frequency and high frequency behaviors. The low frequency behavior is due to the Hertzian dipole effects of vias. The high frequency behavior is due to the radiation of excited cavity modes. Both theoretical analysis …
Zheng Classification In Traditional Chinese Medicine Based On Modified Specular-Free Tongue Images, Ratchadaporn Kanawong, Tayo Obafemi-Ajayi, Jun Yu, Dong Xu, Shao Li, Ye Duan
Zheng Classification In Traditional Chinese Medicine Based On Modified Specular-Free Tongue Images, Ratchadaporn Kanawong, Tayo Obafemi-Ajayi, Jun Yu, Dong Xu, Shao Li, Ye Duan
Electrical and Computer Engineering Faculty Research & Creative Works
Traditional Chinese Medicine practitioners usually observe the color and coating of a patient's tongue to determine ZHENG (such as Cold or Hot ZHENG) and to diagnose different stomach disorders including gastritis. In our previous work, we explored new modalities for clinical characterization of ZHENG in gastritis patients via tongue image analysis using various supervised machine-learning algorithms. We proposed a system that learns from the clinical practitioner's subjective data how to classify a patients health status by extracting meaningful features from tongue images based on color-space models. In this paper, we propose an enhancement to the ZHENG classification system: a coating …
Features For Automated Tongue Image Shape Classification, Tayo Obafemi-Ajayi, Ratchadaporn Kanawong, Dong Xu, Shao Li, Ye Duan
Features For Automated Tongue Image Shape Classification, Tayo Obafemi-Ajayi, Ratchadaporn Kanawong, Dong Xu, Shao Li, Ye Duan
Electrical and Computer Engineering Faculty Research & Creative Works
Inspection of the tongue is a key component in Traditional Chinese Medicine. Chinese medical practitioners diagnose the health status of a patient based on observation of the color, shape, and texture characteristics of the tongue. The condition of the tongue can objectively reflect the presence of certain diseases and aid in the differentiation of syndromes, prognosis of disease and establishment of treatment methods. Tongue shape is a very important feature in tongue diagnosis. A different tongue shape other than ellipse could indicate presence of certain pathologies. In this paper, we propose a novel set of features, based on shape geometry …
Skin-Effect Model For Round Wires In Peec, Albert E. Ruehli, Giulio Antonini, Lijun Jiang
Skin-Effect Model For Round Wires In Peec, Albert E. Ruehli, Giulio Antonini, Lijun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
In this paper we consider the skin-and radiation effects for a thin wire segment. Circuit models are being constructed which are suitable for the modeling of thin wires like the wire bonds. We use the internal-external inductance model for this purpose of including the skin-effect in the partial inductance. These models make it possible to include thin, round conductors in a PEEC model at a much lower cost in compute time. The ultimate goal is to construct a circuit model which can be applied both in the time and frequency domain to signal and power integrity problems. © 2012 IEEE.
Generalized Modal Expansion Of Electromagnetic Field In 2-D Bounded And Unbounded Media, Qi I. Dai, Weng Cho Chew, Yat Hei Lo, Yang G. Liu, Li (Lijun) Jun Jiang
Generalized Modal Expansion Of Electromagnetic Field In 2-D Bounded And Unbounded Media, Qi I. Dai, Weng Cho Chew, Yat Hei Lo, Yang G. Liu, Li (Lijun) Jun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
A generalized modal expansion theory is presented to investigate and illustrate the physics of wave-matter interaction within arbitrary two-dimensional (2-D) bounded and unbounded electromagnetic problems. We start with the bounded case where the field excited by any sources is expanded with a complete set of biorthogonal eigenmodes. In regard to non-Hermitian or nonreciprocal problems, an auxiliary system is constructed to seek for the modal-expansion solution. We arrive at the unbounded case when the boundary tends to infinity or is replaced by the perfectly matched layer (PML). Modes are approximately categorized into two types: trapped modes and radiation modes, which respond …
A New Green's Function Formulation For Modeling Homogeneous Objects In Layered Medium, Yongpin P. Chen, Weng Cho Chew, Lijun Jiang
A New Green's Function Formulation For Modeling Homogeneous Objects In Layered Medium, Yongpin P. Chen, Weng Cho Chew, Lijun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
A new Green's function formulation is developed systematically for modeling general homogeneous (dielectric or magnetic) objects in a layered medium. The dyadic form of the Green's function is first derived based on the pilot vector potential approach. The matrix representation in the moment method implementation is then derived by applying integration by parts and vector identities. The line integral issue in the matrix representation is investigated, based on the continuity property of the propagation factor and the consistency of the primary term and the secondary term. The extinction theorem is then revisited in the inhomogeneous background and a surface integral …
Microwave And Millimeter-Wave Sensors, Systems, And Techniques For Electromagnetic Imaging And Materials Characterization, Andrea Randazzo, Kristen M. Donnell, Yeousong Lee
Microwave And Millimeter-Wave Sensors, Systems, And Techniques For Electromagnetic Imaging And Materials Characterization, Andrea Randazzo, Kristen M. Donnell, Yeousong Lee
Electrical and Computer Engineering Faculty Research & Creative Works
No abstract provided.
Study On Spontaneous Emission In Complex Multilayered Plasmonic System Via Surface Integral Equation Approach With Layered Medium Green's Function, Yongpin P. Chen, Wei E.I. Sha, Wallace C.H. Choy, Lijun Jiang, Weng Cho Chew
Study On Spontaneous Emission In Complex Multilayered Plasmonic System Via Surface Integral Equation Approach With Layered Medium Green's Function, Yongpin P. Chen, Wei E.I. Sha, Wallace C.H. Choy, Lijun Jiang, Weng Cho Chew
Electrical and Computer Engineering Faculty Research & Creative Works
A rigorous surface integral equation approach is proposed to study the spontaneous emission of a quantum emitter embedded in a multi-layered plasmonic structure with the presence of arbitrarily shaped metallic nanoscatterers. With the aid of the Fermi's golden rule, the spontaneous emission of the emitter can be calculated from the local density of states, which can be further expressed by the imaginary part of the dyadic Green's function of the whole electromagnetic system. To obtain this Green's function numerically, a surface integral equation is established taking into account the scattering from the metallic nanoscatterers. Particularly, the modeling of the planar …
Methods For Fast Evaluation Of Self-Energy Matrices In Tight-Binding Modeling Of Electron Transport Systems, Jun Z. Huang, Weng Cho Chew, Yumao Wu, Li (Lijun) Jun Jiang
Methods For Fast Evaluation Of Self-Energy Matrices In Tight-Binding Modeling Of Electron Transport Systems, Jun Z. Huang, Weng Cho Chew, Yumao Wu, Li (Lijun) Jun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
Simulation of quantum carrier transport in nanodevices with non-equilibrium Green's function approach is computationally very challenging. One major part of the computational burden is the calculation of self-energy matrices. The calculation in tight-binding schemes usually requires dealing with matrices of the size of a unit cell in the leads. Since a unit cell always consists of several planes (for example, in silicon nanowire, four atomic planes for [100] crystal orientation and six for [111] and [112]), we show in this paper that a condensed Hamiltonian matrix can be constructed with reduced dimension (∼ 1 / 4 of the original size …
Simultaneous Evaluation Of Multiple Key Material Properties Of Complex Stratified Structures With Large Spatial Extent, Mojtaba Behzad Fallahpour, Hamed Kajbaf, Mohammad Tayeb Ahmad Ghasr, Joseph Toby Case, R. Zoughi
Simultaneous Evaluation Of Multiple Key Material Properties Of Complex Stratified Structures With Large Spatial Extent, Mojtaba Behzad Fallahpour, Hamed Kajbaf, Mohammad Tayeb Ahmad Ghasr, Joseph Toby Case, R. Zoughi
Electrical and Computer Engineering Faculty Research & Creative Works
Measured complex reflection coefficient of a spatially-extended stratified composite structure, using an open-ended waveguide, can be effectively used to extract key material and geometrical characteristics of any given layer. This is accomplished using a combination of an electromagnetic model and corresponding measurement data. Previously, it was shown that one parameter can be extracted if all others are known. However, practically it is desirable to extract as many pieces of information as possible. To this end the model must be "inverted". However, there is no closed-form solution for the inverse problem, given the mathematical complexity of the forward model. Consequently, we …
Alternative Aefie-Efie Method For Broadband Cem Simulations, Jia Liu, Lijun Jiang
Alternative Aefie-Efie Method For Broadband Cem Simulations, Jia Liu, Lijun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
It is well known that electric field integral equation (EFIE) has the low frequency breakdown problem due to the decoupling of electric and magnetic field. Augmented electric field integral equation (AEFIE) method overcomes the low frequency breakdown. However, its performance degrades with the increasing frequency. To obtain a unified method that works for both low and high frequencies, a novel method using the EFIE complement process inside AEFIE is proposed. Numerical results demonstrated that this alternative AEFIE-EFIE method is able to extend integral equations to wide band applications. © 2012 Wiley Periodicals, Inc.
Microwave Absorption Characteristics Of Substituted Ba 0.5sr 0.5m Xfe (12-2x)O 19 (M = Co ²⁺-Zr 4+ And Co 2+-Ti 4+) Sintered Ferrite At X-Band, Charanjeet Singh, S. Bindra Narang, Marina Koledintseva
Microwave Absorption Characteristics Of Substituted Ba 0.5sr 0.5m Xfe (12-2x)O 19 (M = Co ²⁺-Zr 4+ And Co 2+-Ti 4+) Sintered Ferrite At X-Band, Charanjeet Singh, S. Bindra Narang, Marina Koledintseva
Electrical and Computer Engineering Faculty Research & Creative Works
The microwave reflection loss (RL) of four series of synthesized ferrites, Ba0.5Sr0.5CoxZrxFe(12 - 2x)O19 and Ba0.5Sr0.5CoxTixFe(12 - 2x)O19, have been measured using network analyzer in the frequency range from 8.2 to 12.4 GHz. The comprehensive analysis of RL is carried out as a function of substitution, frequency, and thickness. The various models contributing to large RL are described. The composition accompanying maximum microwave absorption is suggested. © 2012 Wiley Periodicals, Inc.
Initial Study And Verification Of A Distributed Fiber Optic Corrosion Monitoring System For Transportation Structures, Hai Xiao, Genda Chen, Zhan Gao, Ying Huang, Fujian Tang
Initial Study And Verification Of A Distributed Fiber Optic Corrosion Monitoring System For Transportation Structures, Hai Xiao, Genda Chen, Zhan Gao, Ying Huang, Fujian Tang
Electrical and Computer Engineering Faculty Research & Creative Works
For this study, a novel optical fiber sensing system was developed and tested for the monitoring of corrosion in transportation systems. The optical fiber sensing system consists of a reference long period fiber gratings (LPFG) sensor for corrosive environmental monitoring and a LPFG sensor coated with a thin film of nano iron and silica particles for steel corrosion monitoring. The environmental effects (such as pH and temperature) are compensated by the use of the reference LPFG sensor. The sensor design, simulation, and experimental validation were performed in this study to investigate the feasibility of the proposed sensing system for corrosion …
Automated Tongue Feature Extraction For Zheng Classification In Traditional Chinese Medicine, Ratchadaporn Kanawong, Tayo Obafemi-Ajayi, Tao Ma, Dong Xu, Shao Li, Ye Duan
Automated Tongue Feature Extraction For Zheng Classification In Traditional Chinese Medicine, Ratchadaporn Kanawong, Tayo Obafemi-Ajayi, Tao Ma, Dong Xu, Shao Li, Ye Duan
Electrical and Computer Engineering Faculty Research & Creative Works
ZHENG, Traditional Chinese Medicine syndrome, is an integral and essential part of Traditional Chinese Medicine theory. It defines the theoretical abstraction of the symptom profiles of individual patients and thus, used as a guideline in disease classification in Chinese medicine. For example, patients suffering from gastritis may be classified as Cold or Hot ZHENG, whereas patients with different diseases may be classified under the same ZHENG. Tongue appearance is a valuable diagnostic tool for determining ZHENG in patients. In this paper, we explore new modalities for the clinical characterization of ZHENG using various supervised machine learning algorithms. We propose a …
Efficient Variation-Aware Em-Semiconductor Coupled Solver For The Tsv Structures In 3d Ic, Yuanzhe Xu, Wenjian Yu, Quan Chen, Lijun Jiang, Ngai Wong
Efficient Variation-Aware Em-Semiconductor Coupled Solver For The Tsv Structures In 3d Ic, Yuanzhe Xu, Wenjian Yu, Quan Chen, Lijun Jiang, Ngai Wong
Electrical and Computer Engineering Faculty Research & Creative Works
In this paper, we present a variational electromagnetic-semiconductor coupled solver to assess the impacts of process variations on the 3D integrated circuit (3D IC) on-chip structures. The solver employs the finite volume method (FVM) to handle a system of equation considering both the full-wave electromagnetic effects and semiconductor effects. With a smart geometrical variation model for the FVM discretization, the solver is able to handle both small-size or large-size variations. Moreover, a weighted principle factor analysis (wPFA) technique is presented to reduce the random variables in both electromagnetic and semiconductor regions, and the spectral stochastic collocation method (SSCM) [10] is …
Scaling Relations And The Role Of Bond-Charge To The Electron Transmission Through Two Coupled Aharonov-Bohm Rings, Cheng-Hsiao Wu, Lam C. Tran, C. A. Cain
Scaling Relations And The Role Of Bond-Charge To The Electron Transmission Through Two Coupled Aharonov-Bohm Rings, Cheng-Hsiao Wu, Lam C. Tran, C. A. Cain
Electrical and Computer Engineering Faculty Research & Creative Works
Electron transport and the exact scaling relations for two irreducibly coupled Aharonov-Bohm (AB) rings with two external terminals attached are investigated. In coupled AB rings, a center common path exists where the phase of the electron wave function can be modulated by two applied fluxes simultaneously. The two coupled rings can be considered as two coupled atoms where Fermi level crossings exist not only between bonding states but also between bonding and anti-bonding states when the applied flux is varied in one of the two cases studied. We show that when the smallest atomic-sized coupled rings are scaled up any …
Character-Based Automated Human Perception Quality Assessment In Document Images, Tayo Obafemi-Ajayi, Gady Agam
Character-Based Automated Human Perception Quality Assessment In Document Images, Tayo Obafemi-Ajayi, Gady Agam
Electrical and Computer Engineering Faculty Research & Creative Works
Large degradations in document images impede their readability and deteriorate the performance of automated document processing systems. Document image quality (IQ) metrics have been defined through optical character recognition (OCR) accuracy. Such metrics, however, do not always correlate with human perception of IQ. When enhancing document images with the goal of improving readability, e.g., in historical documents where OCR performance is low and/or where it is necessary to preserve the original context, it is important to understand human perception of quality. The goal of this paper is to design a system that enables the learning and estimation of human perception …
Resonance Scanning System And Method For Testing Equipment For Electromagnetic Resonances, David Pommerenke, Wei Huang, Peng Shao, Jiang Xiao
Resonance Scanning System And Method For Testing Equipment For Electromagnetic Resonances, David Pommerenke, Wei Huang, Peng Shao, Jiang Xiao
Electrical and Computer Engineering Faculty Research & Creative Works
A resonance scanning system and method for testing equipment for electromagnetic resonances uses a resonance detection subsystem with at least one probe to identify at least one of a resonating location, a resonating frequency and a quality factor of a resonance of the equipment and an automatic scanning subsystem to displace the probe to different testing locations of the equipment so that the resonance detection subsystem can determine if any of the different testing locations of the equipment exhibits electromagnetic resonances.
Finite-Element-Based Generalized Impedance Boundary Condition For Modeling Plasmonic Nanostructures, Shiquan He, Wei E.I. Sha, Lijun Jiang, Wallace C.H. Choy, Weng Cho Chew, Zaiping Nie
Finite-Element-Based Generalized Impedance Boundary Condition For Modeling Plasmonic Nanostructures, Shiquan He, Wei E.I. Sha, Lijun Jiang, Wallace C.H. Choy, Weng Cho Chew, Zaiping Nie
Electrical and Computer Engineering Faculty Research & Creative Works
The superior ability of plasmonic structures to manipulate light has propelled their extensive applications in nanophotonics techniques and devices. Computational electromagnetics plays a critical role in characterizing and optimizing the nanometallic structures. In this paper, a general numerical algorithm, which is different from the commonly used discrete dipole approximation, the finite-difference time-domain, and the surface integral equation (SIE) method, is proposed to model plasmonic nanostructures. In this algorithm, the generalized impedance boundary condition (GIBC) based on the finite element method (FEM) is formulated and converted to the SIE. The plasmonic nanostructures with arbitrary inhomogeneity and shapes are modeled by the …
Efficient Simulation And Analysis Of Quantum Ballistic Transport In Nanodevices With Awe, Jun Z. Huang, Weng Cho Chew, Min Tang, Lijun Jiang
Efficient Simulation And Analysis Of Quantum Ballistic Transport In Nanodevices With Awe, Jun Z. Huang, Weng Cho Chew, Min Tang, Lijun Jiang
Electrical and Computer Engineering Faculty Research & Creative Works
Quantum-mechanical modeling of ballistic transport in nanodevices usually requires solving the Schrdinger equation at multiple energy points within an energy band. To speed up the simulation and analysis, the asymptotic waveform evaluation is introduced in this paper. Using this method, the wave function is only rigorously solved at several sampled energy points, whereas those at other energies are computed through Pad approximation. This allows us to obtain the physical quantities over the whole energy band with very little computational cost. In addition, the accuracy is controllable by a complex frequency hopping algorithm. The validity and efficiency of the proposed method …