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Electrical and Computer Engineering

2016

Missouri University of Science and Technology

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Articles 1 - 30 of 95

Full-Text Articles in Engineering

Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker Dec 2016

Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

Background: In previous research, we introduced an automated, localized, fusion-based approach for classifying uterine cervix squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on digitized histology image analysis. As part of the CIN assessment process, acellular and atypical cell concentration features were computed from vertical segment partitions of the epithelium region to quantize the relative distribution of nuclei.

Methods: Feature data was extracted from 610 individual segments from 61 images for epithelium classification into categories of Normal, CIN1, CIN2, and CIN3. The classification results were compared against CIN labels obtained from two pathologists …


A Novel Supercell-Based Dielectric Grating Dual-Beam Leaky-Wave Antenna For 60-Ghz Applications, Zi Long Ma, Kung Bo Ng, Chi Hou Chan, Li (Lijun) Jun Jiang Dec 2016

A Novel Supercell-Based Dielectric Grating Dual-Beam Leaky-Wave Antenna For 60-Ghz Applications, Zi Long Ma, Kung Bo Ng, Chi Hou Chan, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This communication proposes a novel dual-beam dielectric grating antenna based on the supercell (SC) concept. Through the theoretical analysis of the effective phase constants of the SC, it is found that two space harmonic modes (m=-1 and m=-2) can be simultaneously excited (above the air line) within a certain frequency range. This phenomenon leads to the generation of two radiation beams in the far-field region. At the frequency where the phase constants satisfy β-1=-β-2, the two beams are in symmetric directions with respect to the axis that is perpendicular to the azimuth plane. Different from the conventional periodic structures that …


Strongly Enhanced And Directionally Tunable Second-Harmonic Radiation From A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Ming Fang, Weng Cho Chew, Wallace C.H. Choy Nov 2016

Strongly Enhanced And Directionally Tunable Second-Harmonic Radiation From A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Ming Fang, Weng Cho Chew, Wallace C.H. Choy

Electrical and Computer Engineering Faculty Research & Creative Works

Second-harmonic (SH) generation is tremendously important for nonlinear sensing, microscopy, and communication systems. One of the great challenges of current designs is to enhance the SH signal and simultaneously tune its radiation direction with a high directivity. In contrast to the linear plasmonic scattering dominated by a bulk dipolar mode, a complex surface-induced multipolar source at the doubled frequency sets a fundamental limit to control the SH radiation from metallic nanostructures. In this work, we harness a plasmonic hybridization mechanism together with a special selection rule governing the SH radiation to achieve the high-intensity and tunable-direction emission by a metallic …


A Study Of Scattering From A Layer Of Random Discrete Medium With Hierarchical Equivalent Source Algorithm (Hesa), Chan Fai Lum, Fu Xin, Hong Tat Ewe, Li (Lijun) Jun Jiang Nov 2016

A Study Of Scattering From A Layer Of Random Discrete Medium With Hierarchical Equivalent Source Algorithm (Hesa), Chan Fai Lum, Fu Xin, Hong Tat Ewe, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper is to present a new numerical method which can be used in computational electromagnetics in microwave remote sensing of random discrete medium embedded with irregular shape of scatterers. Current Radiative Transfer (RT) theoretical modeling is normally used to simulate wave propagation in the medium and wave scattering by basic shapes of scatterers, e.g., cylinder, disk, needle or sphere where the scattering of those scatterers was normally derived analytically with some assumption and approximation. To simulate the total backscattering coefficient from a layer of random medium, traditionally it was quite common that Mie phase matrix was used to compute …


Right-Hand Side Effect On The Convergence Of Integral Equation Based Systems, Qin S. Liu, Sheng Sun, Weng Cho Chew, Qi I. Dai, Li (Lijun) Jun Jiang Nov 2016

Right-Hand Side Effect On The Convergence Of Integral Equation Based Systems, Qin S. Liu, Sheng Sun, Weng Cho Chew, Qi I. Dai, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A study of the right-hand side effect for an iterative solver is presented. The right-hand side determines whether a mode can be excited under certain excitation. Based on the matrix equation system Ā · x = b, different formulations are discussed including the electric field integral equation (EFIE), Calderón preconditioned EFIE with electro-quasi-static problems, and the magnetic integral equation (MFIE) with magneto-quasi-static problems. Detailed spectral analysis shows the importance of the weighted right-hand side effect in both the convergence and accuracy of iterative system.


Shape Analysis Of Traffic Flow Curves Using A Hybrid Computational Analysis, Wasim Irshad Kayani, Shikhar P. Acharya, Ivan G. Guardiola, Donald C. Wunsch, B. Schumacher, Isaac Wagner-Muns Nov 2016

Shape Analysis Of Traffic Flow Curves Using A Hybrid Computational Analysis, Wasim Irshad Kayani, Shikhar P. Acharya, Ivan G. Guardiola, Donald C. Wunsch, B. Schumacher, Isaac Wagner-Muns

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper highlights and validates the use of shape analysis using Mathematical Morphology tools as a means to develop meaningful clustering of historical data. Furthermore, through clustering more appropriate grouping can be accomplished that can result in the better parameterization or estimation of models. This results in more effective prediction model development. Hence, in an effort to highlight this within the research herein, a Back-Propagation Neural Network is used to validate the classification achieved through the employment of MM tools. Specifically, the Granulometric Size Distribution (GSD) is used to achieve clustering of daily traffic flow patterns based solely on their …


Water-Soluble Glass Substrate As A Platform For Biodegradable Solid-State Devices, Shihab Md Adnan, Kwangman Lee, Mohammad Tayeb Ahmad Ghasr, Matthew O'Keefe, D. E. Day, Chang-Soo Kim Nov 2016

Water-Soluble Glass Substrate As A Platform For Biodegradable Solid-State Devices, Shihab Md Adnan, Kwangman Lee, Mohammad Tayeb Ahmad Ghasr, Matthew O'Keefe, D. E. Day, Chang-Soo Kim

Materials Science and Engineering Faculty Research & Creative Works

A biodegradable glass material is utilized as a novel functional element of solid-state devices. A water-soluble borate glass substrate serves as the structural platform on which thin film device is built. The glass substrate completely dissolves in a saline solution in approximately 40 h. Intentional failure of the spiral device (RLC resonator circuit) as a result of rapid structural disintegration by dissolution is demonstrated in DC, AC, and RF ranges that agrees well with simulation. Adopting water-soluble glass elements is expected to be a viable approach to develop reliable all-inorganic biodegradable devices that are fully functional during an intended operational …


Polarization Control By Using Anisotropic 3-D Chiral Structures, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha, Wallace C.H. Choy, Tatsuo Itoh Nov 2016

Polarization Control By Using Anisotropic 3-D Chiral Structures, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha, Wallace C.H. Choy, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the mirror symmetry breaking, chiral structures show fantastic electromagnetic (EM) properties involving negative refraction, giant optical activity, circular dichroism and asymmetric transmission. Aligned electric and magnetic dipoles excited in chiral structures contribute to the extraordinary properties. However, the chiral structures that exhibit n -fold rotational symmetry show a limited tunability of the chirality. In this paper, we propose a compact, light, and highly tunable anisotropic chiral structure to overcome this limitation and realize a linear-to-circular polarization conversion. The anisotropy is due to simultaneous excitations of two different pairs of aligned electric and magnetic dipoles. The 3-D omega-shaped structure, …


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 …


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 …


Stochastic Galerkin Methods For Transient Maxwell's Equations With Random Geometries, Yongtao Cheng, Li (Lijun) Jun Jiang Oct 2016

Stochastic Galerkin Methods For Transient Maxwell's Equations With Random Geometries, Yongtao Cheng, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The generalized polynomial chaos expansion was broadly introduced to model systems with uncertain inputs, including random material properties and random computational geometries. This paper focuses solving electromagnetic field when the geometry contains multi-randomness. A linear transformation always maps spatial random variables into grids with fixed length. Hence a great advantage of the method is that the numerical mesh is not changed despite geometrical variations. We applied efficient stochastic Galerkin methods to time-domain Maxwell's equations when thicknesses of two-layer media are uncertain. High-order Runge-Kutta discontinuous Galerkin methods were performed on the resulting system of the expansion coefficients.


Characteristic Analysis For Optical Antennas: A Generalized Equivalent Circuit Model For Nanoparticles, Ying S. Cao, Li (Lijun) Jun Jiang Oct 2016

Characteristic Analysis For Optical Antennas: A Generalized Equivalent Circuit Model For Nanoparticles, Ying S. Cao, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Optical antennas, which are considered for many potential applications, are antennas which work at optical frequencies. At this frequency range, the materials, such as Al, Ag, Au and so on, formerly treated as perfect electric conductor (PEC), now have dispersive and complex permittivity, which complicates most of the methodologies. In this paper, a generalized equivalent circuit model is developed for nanoantennas not only to deal with the dispersivity of permittivity, but also to provide more physical insight. Several examples are used to benchmark the method.


A Novel Coordinate Transformation Based Self-Coupling Computation Approach For The Method Of Moments, Li Li, Lijun Jiang, Sheng Sun, Thomas F. Eibert, Weng Cho Chew Oct 2016

A Novel Coordinate Transformation Based Self-Coupling Computation Approach For The Method Of Moments, Li Li, Lijun Jiang, Sheng Sun, Thomas F. Eibert, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

A new highly accurate and efficient coordinate transformation algorithm is proposed for the evaluation of the self-coupling in the Method of Moments (MoM), which produces usually the strongest contributions to the MoM system matrices. The new algorithm provides an effective solution to remove the singularity due to the Green's function inside the self-couplings. Moreover, the new solution reduces the integral dimension from 4-D to 1-D. Thus, better accuracy and efficiency are obtained for the self-coupling integrals.


A Patch-Resonator-Based Butler Matrix With New Triangular Phase Shifters, Xianshi Jing, Li (Lijun) Jun Jiang, Sheng Sun, Lei Zhu Oct 2016

A Patch-Resonator-Based Butler Matrix With New Triangular Phase Shifters, Xianshi Jing, Li (Lijun) Jun Jiang, Sheng Sun, Lei Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new novel patch based Butler Matrix using 3-dB square-patch coupler and triangular-patch wideband phase shifter is presented. By inserting a via hole along the symmetrical plane of the triangular patch, the bandwidth of the transmitting response is significantly increased. In order to obtain a 45° phase difference and a wideband phase response, a reference line with high characteristic impedance is applied and the length of the feeding line for the triangular-patch structure is adjusted correspondingly. As an application, a patch-based Butler Matrix is designed and fabricated around 4 GHz. The measured patch-based Butler Matrix shows a …


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%.


A Highly Tunable Sub-Wavelength Chiral Structure For Circular Polarizer, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha, Tatsuo Itoh Oct 2016

A Highly Tunable Sub-Wavelength Chiral Structure For Circular Polarizer, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

Chiral structures are composed of periodically arranged asymmetric particles. The asymmetry of chiral particles results in extraordinary properties like negative refraction index, giant optical activity and circular dichroism. Consequently, they have applications in super lens and various polarization controllers. There are two types of chiral structures, namely planar and 3D structures. The planar ones usually have three- or fourfold rotational symmetry, which limits the polarization tuning capability. On the other hand, the 3D prototypes are difficult to fabricate and measure. Here, we propose a highly tunable sub-wavelength 3D chiral structure. It can be conveniently manufactured on the single-layer double-side printed …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


Integrated Microsphere Whispering Gallery Mode Probe For Highly Sensitive Refractive Index Measurement, Hanzheng Wang, Lei Yuan, Cheol-Woon Kim, Jie Huang, Xinwei Lan, Hai Xiao Jun 2016

Integrated Microsphere Whispering Gallery Mode Probe For Highly Sensitive Refractive Index Measurement, Hanzheng Wang, Lei Yuan, Cheol-Woon Kim, Jie Huang, Xinwei Lan, Hai Xiao

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

We report an integrated whispering gallery mode microresonator-based sensor probe for refractive index sensing. The probe was made by sealing a borosilicate glass microsphere into a thin-wall glass capillary pigtailed with a multimode optical fiber. The intensities of the resonant peaks were found decreasing exponentially (linearly in a log scale) with the increasing refractive index of the medium surrounding the capillary. The sensing capability of the integrated probe was tested using sucrose solutions of different concentrations and the resolution was estimated to be about 2.5 x 10-5 in the index range of 1.3458 to 1.3847. The integrated sensor probe …


An Accurate Method Of Energy Use Prediction For Systems With Known Consumption, Jacob A. Mueller, Jonathan W. Kimball May 2016

An Accurate Method Of Energy Use Prediction For Systems With Known Consumption, Jacob A. Mueller, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

An improved method of nonintrusive load monitoring (NILM) using hidden Markov models is proposed. The proposed method is intended for electrical systems with a closed and known set of devices. Systems that meet this constraint are more commonly found in industrial or commercial contexts than the residential settings in which NILM is traditionally studied. The proposed method is designed to support applications relevant to these contexts, such as fault monitoring and system health assessments. To this end, the energy predictions of the disaggregation algorithm offer accurate descriptions of device behavior in time. The accuracy of the proposed method is validated …


The Derived Equivalent Circuit Model For Non-Magnetized And Magnetized Graphene, Ying S. Cao, Li (Lijun) Jun Jiang, Albert E. Ruehli May 2016

The Derived Equivalent Circuit Model For Non-Magnetized And Magnetized Graphene, Ying S. Cao, Li (Lijun) Jun Jiang, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, for the first time the electromagnetic features of graphene are characterized by a circuit model derived instead of fitted from the electric field integral equation (EFIE). The atomically thick graphene is equivalently replaced by an impedance surface. When it is magnetized, the impedance surface is anisotropic with a tensor conductivity. Based on EFIE, the graphene's circuit model can be derived by the partial element equivalency circuit (PEEC) concept. The anisotropic resistivity is modeled using a serial resistor with current control voltage sources (CCVSs). From the derived circuit model, electromagnetic properties of graphene can be conveniently analyzed. This …