Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Electrical and Computer Engineering Faculty Research & Creative Works

Discipline
Keyword
Publication Year

Articles 1021 - 1050 of 3465

Full-Text Articles in Entire DC Network

Enhanced Second Harmonic Generation In A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo Oct 2016

Enhanced Second Harmonic Generation In A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo

Electrical and Computer Engineering Faculty Research & Creative Works

Plasmonic nanostructures that support surface plasmon resonances potentially provide a route for the development of nanoengineered nonlinear optical media. A strong enhancement of second harmonic generation (SHG) in a particle-in-cavity nanoantenna (PIC-NA) is proposed and theoretically demonstrated in this work. The fundamental and second harmonic responses of the PIC-NA are calculated using a self-consistent boundary element method. Through a comparison with the linear field enhancement spectra, the SHG from PIC-NA is boosted by the strongly enhanced fundamental and SH fields arising from the cascaded focusing of large optical energy into the small gap. The proposed 3D plasmonic PIC-NA functions as …

Go to article

Orbital Angular Momentum (Oam) Generation By Composite Pec-Pmc Metasurfaces In Microwave Regime, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha Oct 2016

Orbital Angular Momentum (Oam) Generation By Composite Pec-Pmc Metasurfaces In Microwave Regime, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

Besides amplitude, phase and polarization, wave-front is also an important property of electromagnetic waves. EM waves with helical wavefront carrying orbital angular momentum (OAM) attract more attentions recently for its promising applications in communications. The OAM generation for microwaves was rarely reported. And existing designs are usually very complicated and suffer low efficiency problems. We propose composite PEC (perfect electric conductor)-PMC (perfect magnetic conductor) metasurfaces to convert the LCP (RCP) plane wave with zero OAM to the RCP (LCP) helical EM wave with desired OAM at microwave regime. The conversion efficiency can nearly reach 100%.

Go to article

Finite-Difference Time-Domain Simulation Of The Maxwell-Schrödinger System, Christopher Ryu, Aiyin Liu, Weng C. Chew, Wei Sha, Lijun Jiang Oct 2016

Finite-Difference Time-Domain Simulation Of The Maxwell-Schrödinger System, Christopher Ryu, Aiyin Liu, Weng C. Chew, Wei Sha, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A thorough study on the finite-difference time-domain (FDTD) simulation of the Maxwell-Schrödinger system in the semi-classical regime is given. For the Maxwell part which is treated classically, an alternative approach directly using the vector and scalar potentials (A and Φ) is taken. This approach is stable in the long wavelength regime and removes the need to extract the potentials at every time step. Perfectly matched layer (PML) is developed for this system. For the Schrödinger and quantum mechanical part, minimal coupling is applied to couple the charges to the electromagnetic potentials. Simulation results agree with the theory of quantum coherent …

Go to article

A New Multiple Access Wiretap Channel Model, Mohamed Nafea, Aylin Yener Oct 2016

A New Multiple Access Wiretap Channel Model, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

A new model for the two-user multiple-access wiretap channel is considered. In this model, the legitimate (main) channel is a discrete memoryless channel (DMC), and the wiretapper chooses a fixed-length subset of the channel uses where she has perfect access to the transmitted symbols of both users, while observing the remainder of the transmitted codewords through a second DMC. As such, it generalizes the existing multiple-access wiretap channel models and extends the recently proposed new wiretap channel model to a multiple access setting. An achievable strong secrecy rate region for the model is derived. The achievability is established by solving …

Go to article

The Numerical Contour Deformation Method For Calculating High Frequency Scattered Fields From The 3-D Convex Scatters, Yu Mao Wu, Weng Cho Chew, Ya Qiu Jin, Tie Jun Cui, Li (Lijun) Jun Jiang Oct 2016

The Numerical Contour Deformation Method For Calculating High Frequency Scattered Fields From The 3-D Convex Scatters, Yu Mao Wu, Weng Cho Chew, Ya Qiu Jin, Tie Jun Cui, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

We consider the accuracy improvement of the high frequency scattered fields from the 3-D convex scatter by the Fock current and the incremental length diffraction coefficient (ILDC) technique. We propose the numerical contour deformation method to calculate the Fock currents, and treat them in the scatterer's lit and shadow regions, separately. Then, by adopting the ILDC technique, high frequency scattered fields are clearly formulated in the lit, shadow and transition regions of the 3-D convex scatter, respectively. Compared to the PO scattered field from the 3-D convex sphere, numerical results demonstrate the significant accuracy enhancement of the scattered field via …

Go to article

Investigation Of 12 Μm 4h-Sic Epilayers For Radiation Detection And Noise Analysis Of Front-End Readout Electronics, Khai V. Nguyen, Rahmi O. Pak, Cihan Oner, Feng Zhao, Krishna C. Mandal Oct 2016

Investigation Of 12 Μm 4h-Sic Epilayers For Radiation Detection And Noise Analysis Of Front-End Readout Electronics, Khai V. Nguyen, Rahmi O. Pak, Cihan Oner, Feng Zhao, Krishna C. Mandal

Electrical and Computer Engineering Faculty Research & Creative Works

Schottky barrier radiation detectors were fabricated on 12 μm n-type 4H-SiC epitaxial layers grown on a 4° off-axis highly doped 4H-SiC substrate (0001). Schottky barrier junction properties were characterized through current-voltage (I-V) and capacitance-voltage (C-V) measurements. A diode ideality factor of 1.29 and Schottky barrier height of 1.10 eV were determined from the forward I-V characteristics using a thermionic emission model. A built-in potential of 1.91 V and effective carrier concentration of 1.03 x 1015 cm-3 was calculated from a Mott-Schottky plot of the C-V measurements. Radiation detector performance was evaluated by alpha pulse height spectroscopy (PHS) in …

Go to article

On The Optimal Threshold Voltage Computation Of On-Chip Noise Sensors, Tao Wang, Chun Zhang, Jinjun Xiong, Pei Wen Luo, Liang Chia Cheng, Yiyu Shi Oct 2016

On The Optimal Threshold Voltage Computation Of On-Chip Noise Sensors, Tao Wang, Chun Zhang, Jinjun Xiong, Pei Wen Luo, Liang Chia Cheng, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Runtime noise management systems typically rely on on-chip noise sensors to accurately capture voltage emergencies. As such, the threshold voltage for noise sensors to report emergencies serves as a critical tuning knob between the system failure rate and false alarms. Unfortunately, the problem of optimal threshold voltage computation remains open in literature despite its importance. The problem is further complicated by process variations, which introduce significant variations in load currents and thus in noise across different chips. A uniform noise margin may not work optimally for all the chips. In this paper, we first formulate the problem of minimizing the …

Go to article

A Novel Beam-Steering Nonlinear Nanoantenna With Surface Plasmon Resonance, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Weng Cho Chew Sep 2016

A Novel Beam-Steering Nonlinear Nanoantenna With Surface Plasmon Resonance, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

Plasmonic nanostructures that support surface plasmon (SP) resonance potentially provide a route for the development of nanoengineered nonlinear optical media. In this work, a novel plasmonic particle-in-cavity nanoantenna (PIC-NA) is proposed. The second harmonic generation (SHG) of the PIC-NA under strong localized SP resonance is systematically analyzed by a self-consistent numerical solution based on boundary element method (BEM). The developed method solves the fundamental field and second harmonic (SH) field together iteratively to capture their mutual coupling. Strong enhancement of SHG from PIC-NA is achieved. The SHG enhancement factor is around four orders of magnitude, which is much higher than …

Go to article

Comparison Of Mixed-Mode S-Parameters In Weak And Strong Coupled Differential Pairs, Marina Koledintseva, Tracey Vincent Sep 2016

Comparison Of Mixed-Mode S-Parameters In Weak And Strong Coupled Differential Pairs, Marina Koledintseva, Tracey Vincent

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, it is studied how the rate of coupling (weak vs. strong) in edge-coupled differential transmission lines on a printed circuit board (PCB) affects frequency behavior of mixed-mode S-parameters. This is important for signal integrity (SI), and also may be useful from electromagnetic compatibility (EMC) point of view, since the enhancement of mode conversion (from common-mode to differential mode, and vice versa) may result in common-mode noise in high-speed digital electronics. Slightly imbalanced in length microstrip and strip line differential pairs are considered. The study is done using full-wave numerical electromagnetic simulations. Various technological features are modeled in …

Go to article

Global Adjoint Sensitivity Analysis Of Coupled Coils Using Parameterized Model Order Reduction, Luca De Camillis, Giulio Antonini, Francesco Ferranti, Albert E. Ruehli Sep 2016

Global Adjoint Sensitivity Analysis Of Coupled Coils Using Parameterized Model Order Reduction, Luca De Camillis, Giulio Antonini, Francesco Ferranti, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a parameterized model order reduction technique for efficient global sensitivity analysis of coupled coils. It is based on the use of parameterized models for the electromagnetic matrices and the Krylov matrices of the original and corresponding adjoint systems, and congruence transformations. Numerical results confirm the efficiency and accuracy of the proposed method for global sensitivity analysis over the complete design space of interest.

Go to article

A Full Wave Conductor Modeling Using Augmented Electric Field Integral Equation, Tian Xia, Hui Gan, Michael Wei, Qin Liu, Lijun Jiang, Weng Cho Chew, Henning Braunisch, Kemal Aygun, Zhiguo Qian, Alaeddin Aydiner Sep 2016

A Full Wave Conductor Modeling Using Augmented Electric Field Integral Equation, Tian Xia, Hui Gan, Michael Wei, Qin Liu, Lijun Jiang, Weng Cho Chew, Henning Braunisch, Kemal Aygun, Zhiguo Qian, Alaeddin Aydiner

Electrical and Computer Engineering Faculty Research & Creative Works

A numerical full wave solver is proposed to solve conductor problems in electromagnetics. This method is an extension of the dielectric augmented electric field integral equation (D-AEFIE). Using this method, conductors, from lowly lossy to highly lossy, can be rigorously modeled to capture the conductive losses. Broadband stability can be achieved, thanks to the introduction of the augmentation technique. This paper demonstrates the formulation of this method. A simple and effective preconditioner is introduced to accelerate the convergence. A novel integration scheme is adopted to accurately capture the losses inside the conductor. Finally some numerical examples are shown to support …

Go to article

Coupling Dgtd And Behavioral Macromodel For Transient Heterogeneous Electromagnetic Simulations, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao, Yu Zhang Sep 2016

Coupling Dgtd And Behavioral Macromodel For Transient Heterogeneous Electromagnetic Simulations, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao, Yu Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

A novel transient field-circuit cosimulation method based on the discontinuous Galerkin time domain (DGTD) method and circuit behaviour macromodels for heterogeneous electromagnetics such as EMC problems is proposed. The traditional field-circuit simulation method needs to know the detail of the circuits, which cannot handle problems with unknown systems due to IP protections. To overcome this problem, the proposed method utilizes the artificial neural network (ANN) to create trainable behavioral macromodels of the unknown circuits based on the port currents and port voltages. The obtained macromodel is then coupled with DGTD that describes the behavior of electromagnetic subsystem to form equations …

Go to article

Approximated Proportionate Affine Projection Algorithms For Block-Sparse Identification, Felix Albu, Jianming Liu, Steven L. Grant Sep 2016

Approximated Proportionate Affine Projection Algorithms For Block-Sparse Identification, Felix Albu, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper two block-sparse approximated memory improved proportionate affine projection algorithm are proposed for block sparse system identification. An approximation is used for a recently proposed family of block-sparse proportionate affine projection algorithms. It is shown that the proposed algorithms have close convergence performance to the original ones, and they are less numerically complex. An investigation of the influence of their parameters is also presented.

Go to article

Time-Domain Partial Element Equivalent Circuit Solver Including Non-Linear Magnetic Materials, Daniele Romano, Giulio Antonini, Albert E. Ruehli Sep 2016

Time-Domain Partial Element Equivalent Circuit Solver Including Non-Linear Magnetic Materials, Daniele Romano, Giulio Antonini, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel partial element equivalent circuit formulation to handle 3-D non-linear problems. Since the displacement currents are taken into account, the proposed formulation is not restricted to low-frequency applications, although the propagation delays are neglected. The non-linear problem is solved by means of the Newton-Raphson algorithm. Special care is taken in order to analytically compute the Jacobian of the problem. Furthermore, an adaptive setting of the time step is adopted in the transient analysis allowing to maintain the size of the time step as large as possible while preserving the accuracy. Computed results for a closed magnetic …

Go to article

Selective Body Biasing For Post-Silicon Tuning Of Sub-Threshold Designs: A Semi-Infinite Programming Approach With Incremental Hypercubic Sampling, Hui Geng, Jianming Liu, Jinglan Liu, Pei Wen Luo, Liang Chia Cheng, Steven L. Grant, Yiyu Shi Sep 2016

Selective Body Biasing For Post-Silicon Tuning Of Sub-Threshold Designs: A Semi-Infinite Programming Approach With Incremental Hypercubic Sampling, Hui Geng, Jianming Liu, Jinglan Liu, Pei Wen Luo, Liang Chia Cheng, Steven L. Grant, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Sub-threshold designs have become a popular option in many energies constrained applications. However, a major bottleneck for these designs is the challenge in attaining timing closure. Most of the paths in sub-threshold designs can become critical paths due to the purely random process variation on threshold voltage, which exponentially impacts the gate delay. In order to address timing violations caused by process variation, post-silicon tuning is widely used through body biasing technology, which incurs heavy power and area overhead. Therefore, it is imperative to select only a small group of the gates with body biasing for post-silicon-tuning. In this paper, …

Go to article

X-Ray Absorption Fine Structure Of Zno Thin Film On Si And Sapphire Grown By Mocvd, Jieping Xin, Chieh Miao Chang, Chih Han Hsueh, Jyh Fu Lee, Jin Ming Chen, Hao Hsiung Lin, Na Lu, Ian T. Ferguson, Yongjing Guan, Lingyu Wan, Qingyi Yang, Zhe Chuan Feng Aug 2016

X-Ray Absorption Fine Structure Of Zno Thin Film On Si And Sapphire Grown By Mocvd, Jieping Xin, Chieh Miao Chang, Chih Han Hsueh, Jyh Fu Lee, Jin Ming Chen, Hao Hsiung Lin, Na Lu, Ian T. Ferguson, Yongjing Guan, Lingyu Wan, Qingyi Yang, Zhe Chuan Feng

Electrical and Computer Engineering Faculty Research & Creative Works

X-ray absorption fine structure has been used to study the electronic structure, and bond length of ZnO thin films grown on sapphire and Si substrates by metalorganic chemical vapor deposition. X-ray absorption near edge structure (XANES) of O and Zn K-edge were shown, and a detailed analysis of extended x-ray absorption fine structure (EXAFS) of Zn K-edge indicates that difference substrates result in the contraction of Zn-O bond length.

Go to article

A New Wiretap Channel Model And Its Strong Secrecy Capacity, Mohamed Nafea, Aylin Yener Aug 2016

A New Wiretap Channel Model And Its Strong Secrecy Capacity, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new wiretap channel (WTC) model with a discrete memoryless (DM) main channel and a wiretapper who noiselessly observes a fixed portion, of her choice, of the transmitted symbols, while observing the remaining transmitted symbols through another DM channel (DMC), is considered. The strong secrecy capacity of the model is identified. The achievability is established using the output statistics of random binning framework which exploits the duality between source and channel coding problems. The converse is derived by upper bounding the secrecy capacity of an equivalent model with the secrecy capacity of a DM-WTC. This result generalizes …

Go to article

The Multiple Access Wiretap Channel Ii With A Noisy Main Channel, Mohamed Nafea, Aylin Yener Aug 2016

The Multiple Access Wiretap Channel Ii With A Noisy Main Channel, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

A two-transmitter multiple access wiretap channel II (MAC-WT-II) with a discrete memoryless (DM) main channel is investigated. Two models for the wiretapper, who chooses a fixed-length subset of the channel uses and observes erasures outside this subset, are proposed. In the first model, in each position of the subset, the wiretapper noiselessly observes either the first or the second user's symbol, while in the second model, the wiretapper observes a noiseless superposition of the two symbols. Achievable strong secrecy rate regions for the two models are derived. The achievability is established by solving a dual secret key agreement problem in …

Go to article

A Fast Filtering Block-Sparse Proportionate Affine Projection Sign Algorithm, Felix Albu, Jianming Liu, Steven L. Grant Aug 2016

A Fast Filtering Block-Sparse Proportionate Affine Projection Sign Algorithm, Felix Albu, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new proportionate affine projection sign algorithm for block-sparse identification using a fast recursive filtering procedure and dichotomous coordinate descent iterations is proposed. It is shown that the proposed algorithm is a good candidate for network echo cancellation systems operating under impulsive environments.

Go to article

Free Deterministic Equivalents For The Analysis Of Mimo Multiple Access Channel, An An Lu, Xiqi Gao, Chengshan Xiao Aug 2016

Free Deterministic Equivalents For The Analysis Of Mimo Multiple Access Channel, An An Lu, Xiqi Gao, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a free deterministic equivalent is proposed for the capacity analysis of the multi-input multi-output (MIMO) multiple access channel (MAC) with a more general channel model compared to previous works. In particular, a MIMO MAC with one base station (BS) equipped with several distributed antenna sets is considered. Each link between a user and a BS antenna set forms a jointly correlated Rician fading channel. The analysis is based on operator-valued free probability theory, which broadens the range of applicability of free probability techniques tremendously. By replacing independent Gaussian random matrices with operator-valued random variables satisfying certain operator-valued …

Go to article

The Equivalent Circuit Model For Electrostatic And Magnetostatic Biased Tunable Graphene As The Absorption Material, Ying S. Cao, Li (Lijun) Jun Jiang, Albert E. Ruehli Jul 2016

The Equivalent Circuit Model For Electrostatic And Magnetostatic Biased Tunable Graphene As The Absorption Material, Ying S. Cao, Li (Lijun) Jun Jiang, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

Graphene is being proposed as a new nano material for EMC shielding and absorption due to its tunable resistive characteristics. The surface conductivity of graphene can be flexibly tuned by the electrostatic and magnetostatic bias applied on the graphene surface. Hence, its absorption and radiation characteristics of graphene are changed accordingly. The static electric bias applied on the graphene patch can change the chemical potential and the surface conductivity of graphene. The static magnetic field can make the conductivity a dispersive and anisotropic tensor, which complicates most modeling methodologies. In this paper, a novel equivalent circuit model is proposed for …

Go to article

A Novel Data Pattern Dependent Electromagnetic Emission Modeling For High Speed Multi-Channel Interconnects, Nick K.H. Huang, Li (Lijun) Jun Jiang, Xingyun Luo, Huichun Yu, Huasheng Ren Jul 2016

A Novel Data Pattern Dependent Electromagnetic Emission Modeling For High Speed Multi-Channel Interconnects, Nick K.H. Huang, Li (Lijun) Jun Jiang, Xingyun Luo, Huichun Yu, Huasheng Ren

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic interference (EMI) is becoming more serious when the data rate of the digital system continues increasing. However, its modeling and analysis are very challenging. In this paper, a novel electromagnetic superposition method is developed to model the electromagnetic emission for the high speed multi-channels on IC packagings. It employs the equivalence principle to obtain the electromagnetic field response over a broad spectrum. Then it uses the linear property of the passive parasitic system to superpose the contribution of different signal patterns. As a result, with limited pre-calculations, it is very convenient to compute the electromagnetic emission efficiently from different …

Go to article

Linear Precoding For Cognitive Multiple Access Wiretap Channel With Finite-Alphabet Inputs, Juening Jin, Chengshan Xiao, Meixia Tao, Wen Chen Jul 2016

Linear Precoding For Cognitive Multiple Access Wiretap Channel With Finite-Alphabet Inputs, Juening Jin, Chengshan Xiao, Meixia Tao, Wen Chen

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates the linear precoder design for cognitive multiple-access wiretap channel (CMAC-WT), where two secondary-user transmitters (STs) communicate with one secondary-user receiver (SR) in the presence of an eavesdropper and subject to interference threshold constraints at primary-user receivers (PRs). It designs linear precoders to maximize the ergodic secrecy sum rate for multiple-input multiple-output (MIMO) CMAC-WT under finite-alphabet inputs and statistical channel state information (CSI). For this non-convex problem, a two-layer algorithm is proposed by embedding the convex-concave procedure into an outer approximation framework. The key idea of this algorithm is to reformulate the approximated ergodic secrecy sum rate as …

Go to article

Effect Of Exposure Conditions On The Long-Term Dielectric Properties Of Mortar Samples Containing Asr Gel, Ashkan Hashemi, Kristen M. Donnell, R. Zoughi, Mehdi Rashidi, K. E. Kurtis Jul 2016

Effect Of Exposure Conditions On The Long-Term Dielectric Properties Of Mortar Samples Containing Asr Gel, Ashkan Hashemi, Kristen M. Donnell, R. Zoughi, Mehdi Rashidi, K. E. Kurtis

Electrical and Computer Engineering Faculty Research & Creative Works

Alkali-silica reaction (ASR) is a chemical reaction between alkalis present in portland cement and amorphous or otherwise disordered siliceous minerals in particular aggregates. Through this reaction, reactive silica binds with hydroxyl and alkali ions and forms a gel, known as ASR gel. Recently, microwave materials characterization techniques have shown great potential for detecting ASR in mortar. However, the comprehensive understanding of variables that affect the extent of ASR in mortar and their interaction with microwave signals, in particular the effect of environmental exposure conditions requires more investigations. Therefore, parameters related to these conditions must be considered when using microwave techniques …

Go to article

Multi-Sensor Integration To Map Odor Distribution For The Detection Of Chemical Sources, Xiang Gao, Levent Acar Jul 2016

Multi-Sensor Integration To Map Odor Distribution For The Detection Of Chemical Sources, Xiang Gao, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

This paper addresses the problem of mapping odor distribution derived from a chemical source using multi-sensor integration and reasoning system design. Odor localization is the problem of finding the source of an odor or other volatile chemical. Most localization methods require a mobile vehicle to follow an odor plume along its entire path, which is time consuming and may be especially difficult in a cluttered environment. To solve both of the above challenges, this paper proposes a novel algorithm that combines data from odor and anemometer sensors, and combine sensors' data at different positions. Initially, a multi-sensor integration method, together …

Go to article

Managing Contingencies In Smart Grids Via The Internet Of Things, Stefano Ciavarella, Jhi Young Joo, Simone Silvestri Jul 2016

Managing Contingencies In Smart Grids Via The Internet Of Things, Stefano Ciavarella, Jhi Young Joo, Simone Silvestri

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a framework for contingency management using smart loads, which are realized through the emerging paradigm of the Internet of things. The framework involves the system operator, the load serving entities (LSEs), and the end-users with smart home management systems that automatically control adjustable loads. The system operator uses an efficient linear equation solver to quickly calculate the load curtailment needed at each bus to relieve congested lines after a contingency. Given this curtailment request, an LSE calculates a power allowance for each of its end-use customers to maximize the aggregate user utility. This large-scale NP-hard problem is …

Go to article

Secure Massive Mimo Transmission With An Active Eavesdropper, Yongpeng Wu, Robert Schober, Derrick Wing Kwan Ng, Chengshan Xiao, Giuseppe Caire Jul 2016

Secure Massive Mimo Transmission With An Active Eavesdropper, Yongpeng Wu, Robert Schober, Derrick Wing Kwan Ng, Chengshan Xiao, Giuseppe Caire

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we investigate secure and reliable transmission strategies for multi-cell multi-user massive multiple-input multiple-output systems with a multi-Antenna active eavesdropper. We consider a time-division duplex system where uplink training is required, and an active eavesdropper can attack the training phase to cause pilot contamination at the transmitter. This forces the precoder used in the subsequent downlink transmission phase to implicitly beamform toward the eavesdropper, thus increasing its received signal power. Assuming matched filter precoding and artificial noise (AN) generation at the transmitter, we derive an asymptotic achievable secrecy rate when the number of transmit antennas approaches infinity. For …

Go to article

Embedding The Behavior Macromodel Into Tdie For Transient Field-Circuit Simulations, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao Jul 2016

Embedding The Behavior Macromodel Into Tdie For Transient Field-Circuit Simulations, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao

Electrical and Computer Engineering Faculty Research & Creative Works

A novel transient field-circuit simulation method based on the time-domain integral equation (TDIE) and circuit macromodels is proposed. The traditional field-circuit simulation process constructs Kirchoff's equations for linear or nonlinear lumped circuits, which cannot handle problems with unknown circuit structure. The proposed method creates parametric behavior macromodels to represent the port constitutive relations of the circuits. Artificial neural network technique is adopted to estimate the model parameters based on the known port voltages and currents. Then, the obtained macromodel is coupled with TDIE that describes the behavior of electromagnetic subsystem to form the equations of a whole system, which can …

Go to article

Simultaneous Specimen Current And Time-Dependent Cathodoluminescence Measurements On Gallium Nitride, E. M. Campo, L. Hopkins, M. Pophristic, I. T. Ferguson Jun 2016

Simultaneous Specimen Current And Time-Dependent Cathodoluminescence Measurements On Gallium Nitride, E. M. Campo, L. Hopkins, M. Pophristic, I. T. Ferguson

Electrical and Computer Engineering Faculty Research & Creative Works

Time-dependent cathodoluminescence (CL) and specimen current (SC) are monitored to evaluate trapping behavior and evolution of charge storage. Examination of CL and SC suggests that the near band edge emission in GaN is reduced primarily by the activation of traps upon irradiation, and Gallium vacancies are prime candidates. At the steady state, measurement of the stored charge by empiric-analytical methods suggests that all available traps within the interaction volume have been filled, and that additional charge is being stored interstitially, necessarily beyond the interaction volume. Once established, the space charge region is responsible for the steady state CL emission and, …

Go to article

Waveguide Probe For Nondestructive Material Characterization, Mohammad Tayeb Ahmad Ghasr, Matthew Kempin, R. Zoughi Jun 2016

Waveguide Probe For Nondestructive Material Characterization, Mohammad Tayeb Ahmad Ghasr, Matthew Kempin, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

An open-ended waveguide probe including a finite flange extending outwardly and functioning as an infinite flange. A signal source provides a microwave signal to the waveguide, which in turn transmits microwave electromagnetic energy incident upon an object to be tested. The finite flange at the waveguide's aperture is shaped to reduce scattering of the electromagnetic field reflected from the object and received by the aperture. The probe is adapted for coupling to a receiver for sampling the reflected electromagnetic field received by the aperture and the receiver is adapted for coupling to a processor for determining at least one material …

Go to article

First Prev Next Last