Engineering Commons^™

Surface Waves Extraction And Their Effect On Effective Material Parameters Of Metamaterials, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

We investigate the influence of the finite width of the metamaterial slabs. The surface waves excited in finite-width slabs are numerically extracted by the rigorous coupled-wave analysis method. The magnitudes and decay rates of surface waves are analyzed for different materials and geometries. A general homogenization method based on the analysis of appropriately defined macroscopic fields in metamaterial cells is proposed to retrieve the effective material parameters as functions of position. The effects of surface waves on effective material parameters are studied.

Mixing Of Spin And Orbital Angular Momenta Via Second-Harmonic Generation In Plasmonic And Dielectric Chiral Nanostructures, Xiaoyan Y.Z. Xiong, Ahmed Al-Jarro, Li (Lijun) Jun Jiang, Nicolae C. Panoiu, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

We present a theoretical study of the characteristics of the nonlinear spin-orbital angular momentum coupling induced by second-harmonic generation in plasmonic and dielectric nanostructures made of centrosymmetric materials. In particular, the connection between the phase singularities and polarization helicities in the longitudinal components of the fundamental and second-harmonic optical fields and the scatterer symmetry properties are discussed. By in-depth comparison between the interaction of structured optical beams with plasmonic and dielectric nanostructures, we have found that all-dielectric and plasmonic nanostructures that exhibit magnetic and electric resonances have comparable second-harmonic conversion efficiency. In addition, mechanisms for second-harmonic enhancement for single and …

Nanoselective Area Growth Of Defect-Free Thick Indium-Rich Ingan Nanostructures On Sacrificial Zno Templates, Renaud Puybaret, David J. Rogers, Youssef El Gmili, Suresh Sundaram, Matthew B. Jordan, Xin Li, Gilles Patriarche, Ferechteh H. Teherani, Eric V. Sandana, Philippe Bove, Paul L. Voss, Ryan Mcclintock, Manijeh Razeghi, Ian Ferguson

Electrical and Computer Engineering Faculty Research & Creative Works

Nano selective area growth (NSAG) by metal organic vapor phase epitaxy of high-quality InGaN nanopyramids on GaN-coated ZnO/c-sapphire is reported. Nanopyramids grown on epitaxial low-temperature GaN-on-ZnO are uniform and appear to be single crystalline, as well as free of dislocations and V-pits. They are also indium-rich (with homogeneous 22% indium incorporation) and relatively thick (100 nm). These properties make them comparable to nanostructures grown on GaN and AlN/Si templates, in terms of crystallinity, quality, morphology, chemical composition and thickness. Moreover, the ability to selectively etch away the ZnO allows for the potential lift-off and transfer of the InGaN/GaN nanopyramids onto …

Design Of Dual Loaded Rfid Tag For Higher Order Modulations, Shadi Ebrahimi-Asl, Mohammad Tayeb Ahmad Ghasr, Maciej Jan Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Methods, systems, and apparatus for an improved antenna, specifically a T-match bowtie antenna system, including a t-match antenna having a first side and a second side, wherein the antenna is dual loaded; a first load soldered to the first side of the antenna; a second load soldered to the second side of the antenna; and a gap defined by the space between the first load and the second load, wherein the gap is approximately one millimeter; where the antenna is capable of providing quasi-32-QAM encoding.

Machine Learning Based Mom (Ml-Mom) For Parasitic Capacitance Extractions, He Ming Yao, Yu Wei Qin, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper is a rethinking of the conventional method of moments (MoM) using the modern machine learning (ML) technology. By repositioning the MoM matrix and unknowns in an artificial neural network (ANN), the conventional linear algebra MoM solving is changed into a machine learning training process. The trained result is the solution. As an application, the parasitic capacitance extraction broadly needed by VLSI modeling is solved through the proposed new machine learning based method of moments (ML-MoM). The multiple linear regression (MLR) is employed to train the model. The computations are done on Amazon Web Service (AWS). Benchmarks demonstrated the …

Linear Precoding For Fading 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

We investigate the fading cognitive multiple-access wiretap channel (CMAC-WT), in which two secondary-user transmitters (STs) send secure messages to a secondary-user receiver (SR) in the presence of an eavesdropper and subject to interference threshold constraints at multiple primary-user receivers (PRs). We design linear precoders to maximize the average secrecy sum rate for a multiple-input-multiple-output (MIMO) fading CMAC-WT under finite-alphabet inputs and statistical channel state information at STs. For this nondeterministic polynomial-time NP-hard problem, we utilize an accurate approximation of the average secrecy sum rate to reduce the computational complexity and then present a two-layer algorithm by embedding the convex-concave procedure …

Stress And Thermal Characterization Of 4h-Sic Microelectromechanical Structures, Colton Wells, Jheng Yi Jiang, Ting Fu Chang, Chih Fang Huang, Jiaxin Ke, Weijun Luo, Guangrui Xia, Kuan Yew Cheong, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

In this letter, the potential of single crystalline 4H-polytype silicon carbide (4H-SiC) based microelectromechanical structures as resistance thermometer for high temperature sensing were explored. A dopant-selective photoelectrochemical etching process was applied to release the sensing element – suspended microstructures on 4H-SiC substrate. Residual stress and stress gradient in the microstructure before and after release was examined by micro-Raman spectroscopy. Electrical resistance of the suspended microstructures at different temperatures were characterized and analyzed by a temperature-dependent electron mobility model.

Sure: A Novel Approach For Self Healing Battery Starved Users Using Energy Harvesting, Mohamed Y. Selim, Ahmad Alsharoa, Ahmed E. Kamal, Mohammed Alnuem

Electrical and Computer Engineering Faculty Research & Creative Works

Radio Frequency (RF) energy harvesting holds a promising future for energizing low power mobile devices in next generation wireless networks. Harvesting from a dedicated RF energy source acquires much more energy than simply harvesting from ambient RF sources. In this paper, novel Self-healing of Users equipment by RF Energy transfer scheme is introduced between the network operator and battery starved users to heal and extend their battery life time by sending dedicated energy from different sources in order to be aggregated and harvested by starved users. This approach depends on the concept of Energy as a Service where the network …

Hypothetical Cases In Engineering Ethics, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

An important educational subject for engineering students is engineering ethics. Common instructional objectives are to develop knowledge of ethical principles, e.g. professional codes, and to apply these principles to specific situations. Case studies are useful instructional examples and exercises and cases are central to student ethics competitions. Historical case studies emphasize the relevance of ethics in engineering work. Hypothetical case studies can address specific ethical principles and provide great design flexibility. This paper discusses hypothetical cases in engineering ethics in the context of instructional exercises or student competitions. Recommendations are given for the development of versatile cases and for approaching …

Transient Analysis Of Dispersive Power-Ground Plate Pairs With Arbitrarily Shaped Antipads By The Dgtd Method With Wave Port Excitation, Ping Li, Li Jun Jiang, Hakan Bagci

Electrical and Computer Engineering Faculty Research & Creative Works

A discontinuous Galerkin time-domain (DGTD) method analyzing signal/power integrity on multilayered power-ground parallel plate pairs is proposed. The excitation is realized by introducing wave ports on the antipads where electric/magnetic current sources are represented in terms of the eigenmodes of the antipads. Since closed-forms solutions do not exist for the eigenmodes of the arbitrarily shaped antipads, they have to be calculated using numerical schemes. Spatial orthogonality of the eigenmodes permits determination of each mode's temporal expansion coefficient by integrating the product of the electric field and the mode over the wave port. The temporal mode coefficients are then Fourier transformed …

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

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the static magnetic field, the conductivity for graphene becomes a dispersive and anisotropic tensor, which complicates most modeling methodologies. In this communication, a novel equivalent circuit model is proposed for graphene with the magnetostatic bias based on the electric field integral equation. To characterize the anisotropic property of the biased graphene, the resistive part of the unit circuit is replaced by a resistor in series with current-controlled voltage sources (CCVSs). The CCVSs account for the off-diagonal parts of the surface conductivity tensor for the magnetized graphene. This proposed method is benchmarked with numerical examples. This communication also provides …

Record: Temporarily Randomized Encoding Of Combinational Logic For Resistance To Data Leakage From Hardware Trojan, Travis E. Schulze, Kevin Kwiat, Charles Kamhoua, Shih Chieh Chang, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Many design companies have gone fabless and rely on external fabrication facilities to produce chips due to increasing cost of semiconductor manufacturing. However, not all of these facilities can be considered trustworthy; some may inject hardware Trojans and jeopardize the security of the system. One common objective of hardware Trojans is to a establish side channel for data leakage. While extensive literature exists on various defensive measures, almost all of them focus on preventing the establishment of side channels and can be compromised if attackers gain access to the physical chip and can perform reverse engineering between multiple fabrication runs. …

A Collimated Surface-Wave-Excited High-Impedance Surface Leaky-Wave Antenna, Zi Long Ma, Chi Hou Chan, Kung Bo Ng, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This letter presents a novel high-impedance surface (HIS)-based leaky-wave antenna excited by collimated surface wave (SW). The proposed antenna consists of two identical SW launchers (SWLs) and an HIS structure. Regarding the SWL, it is based on an offset-fed parabolic reflector. By using the substrate-integrated waveguide technique, the reflector system is integrated in the planar substrate. For the HIS, it is formed by a periodically arranged rectangular microstrip patch array. The proposed SWL can generate collimated SW with the propagation mode. With the perturbation of the HIS, the guided SW can be transformed to m = -1 space-harmonic-mode leaky wave. …

An Efficient Numerical Contour Deformation Method For Calculating Electromagnetic Scattered Fields From 3-D Convex Scatterers, 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 3-D convex scatterers. The Fock currents from the convex scatterers are carefully studied. Furthermore, we propose the numerical contour deformation method to calculate the Fock currents with frequency independent workload and error controllable accuracy. Then, by adopting the Fock currents and the incremental length diffraction coefficient (ILDC) technique, the scattered fields are clearly formulated. Compared to physical optics (PO) scattered fields from 3-D convex sphere, numerical results demonstrate significant accuracy enhancement of the scattered field via the Fock current approach.

Vehicle Base Station, Emad William Saad, J. L. Vian, Matthew A. Vavrina, J. A. Nisbett, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

A system to load and unload material from a vehicle comprises a vehicle base station and an assembly to autonomously load and unload material from the vehicle.

Low Frequency Behavior Of Cvd Graphene From Dc To 40 Ghz, Rong Wang, Salahuddin Raju, Mansun Chan, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic behaviour of chemical vapor deposition (CVD) graphene at low frequencies is still a mystery. No conclusion is made from the experimental point of views. We systematically investigate the electromagnetic response of graphene at microwave frequencies, which are from direct current (DC) to 40 GHz. Both a coplanar transmission line embedded with different-sized graphene flakes of 48 x 48 and 48 x 240 μm2 and a microwave termination based on the graphene sheet of 6 x 6mm2 are manufactured through standard microfabrication procedures. We conclude that CVD graphene behaves as a frequency-independent surface resistance at the microwave frequencies, which is …

Ultrathin Complementary Metasurface For Orbital Angular Momentum Generation At Microwave Frequencies, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic (EM) waves with helical wave front carry orbital angular momentum (OAM), which is associated with the azimuthal phase of the complex electric field. OAM is a new degree of freedom in EM waves and is promising for channel multiplexing in the communication system. Although the OAM-carrying EM wave attracts more and more attention, the method of OAM generation at microwave frequencies still faces challenges, such as efficiency and simulation time. In this communication, by using the circuit theory and equivalence principle, we build two simplified models, one for a single scatter and one for the whole metasurface to predict …

Volterra Series-Based Time-Domain Macromodeling Of Nonlinear Circuits, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Jose E. Schutt-Aine, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

Volterra series (VS) representation is a powerful mathematical model for nonlinear circuits. However, the difficulties in determining higher order Volterra kernels limited its broader applications. In this paper, a systematic approach that enables a convenient extraction of Volterra kernels from X-parameters is presented. A concise and general representation of the output response due to arbitrary number of input tones is given. The relationship between Volterra kernels and X-parameters is explicitly formulated. An efficient frequency sweep scheme and an output frequency indexing scheme are provided. The least square linear regression method is employed to separate different orders of Volterra kernels at …

The Error Control Of Mixed-Form Fast Multipole Algorithm Based On The High-Order Multipole Rotation, Ling Ling Meng, Xiaoyan Y.Z. Xiong, Tian Xia, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this letter, the mixed-form fast multipole algorithm (MF-FMA) with feasible error controllability is implemented through high-order multipole rotation that can make the translation matrices very sparse. The saving of both storage and CPU time makes it attainable to increase the number of harmonics in the middle frequency regime, thus shifting up the transition region of MF-FMA. Consequently, the broadband accuracy of the MF-FMA can be improved significantly.

Decentralized Fault Diagnosis And Prognosis Scheme For Interconnected Nonlinear Discrete-Time Systems, Hasan Ferdowsi, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper deals with the design of a decentralized fault diagnosis and prognosis scheme for interconnected nonlinear discrete-time systems which are modelled as the interconnection of several subsystems. For each subsystem, a local fault detector (LFD) is designed based on the dynamic model of the local subsystem and the local states. Each LFD consists of an observer with an online neural network (NN)-based approximator. The online NN approximators only use local measurements as their inputs, and are always turned on and continuously learn the interconnection as well as possible fault function. A fault is detected by comparing the output of …

Review—The Current And Emerging Applications Of The Iii-Nitrides, Chuanle Zhou, Amirhossein Ghods, Vishal G. Saravade, Paresh V. Patel, Kelcy L. Yunghans, Cameron Ferguson, Yining Feng, Bahadir Kucukgok, Na Lu, Ian T. Ferguson

Electrical and Computer Engineering Faculty Research & Creative Works

III-Nitrides are attracting considerable attention as promising materials for a wide variety of applications due to their wide coverage of direct bandgap range, high electron mobility, high thermal stability and many other exceptional properties. The light-emitting diodes based on III-Nitrides revolutionize the solid-state lighting industry. III-Nitrides based solar cells, and thermoelectric generators support the sustainable energy progress, and the III-Nitrides are better alternatives for power and radio frequency (RF) electronics compared with silicon. The doped III-Nitrides' magnetic properties and sensitivity to radiation can contribute to novel spintronic and nuclear detection devices. This paper will review III-nitride material properties and their …

The Ill-Nitrides As A Universal Compound Semiconductor Material: A Review, Chuanle Zhou, Amirhossein Ghods, Vishal G. Saravade, Paresh V. Patel, Kelcy L. Yunghans, Cameron Ferguson, Yining Feng, Xiaodong Jiang, Bahadir Kucukgok, Na Lu, Ian T. Ferguson

Electrical and Computer Engineering Faculty Research & Creative Works

III-nitrides are attracting considerable attention as promising materials for a wide variety of applications due to their wide coverage of direct bandgap range, high electron mobility, high thermal stability and many other exceptional properties. The light-emitting diodes based on Ill-nitrides revolutionize the solid-state lighting industry. Ill-nitrides based solar cells, and thermoelectric generators support the sustainable energy progress, and the III-nitrides are better alternatives for power and radio frequency (RF) electronics compared with silicon. The doped Ill-nitrides' magnetic properties and sensitivity to radiation can contribute to novel spintronic and nuclear detection devices. This paper will review Ill-nitride material properties and their …

A Study Of Scattering From Snow Embedded With Non-Spherical Shapes Of Scatterers With Relaxed Hierarchical Equivalent Source Algorithm (Rhesa), Chan Fai Lum, Fu Xin, Hong Tat Ewe, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Remote sensing has been used widely in studying the earth terrain such as snow or sea ice due to its fast, convenient and long-term monitoring capabilities. SAR images acquired could be used to analyze the condition of snow, snow water equivalent (SWE), surface roughness and others. Theoretical models have also been developed to understand how microwave interacts with the snow medium and the scatterers embedded inside the medium. Conventionally, spherical shape of scatterers is commonly used to represent the ice particles embedded inside snow where the actual shape of scatterers can vary. This paper is to present a theoretical model …

No-Boundary Thinking In Bioinformatics, Jason H. Moore, Steven F. Jennings, Casey S. Greene, Lawrence E. Hunter, Andy D. Perkins, Clarlynda Williams-Devane, Donald C. Wunsch, Zhongming Zhao, Xiuzhen Huang

Electrical and Computer Engineering Faculty Research & Creative Works

The following sections are included:
Bioinformatics is a Mature Discipline
The Golden Era of Bioinformatics Has Begun
No-Boundary Thinking in Bioinformatics
References

Decision Process In Mcdm With Large Number Of Criteria And Heterogeneous Risk Preferences, Jian Liu, Hong Kuan Zhao, Zhao Bin Li, Si Feng Liu

Electrical and Computer Engineering Faculty Research & Creative Works

A new decision process is proposed to address the challenge that a large number of criteria in the multi-criteria decision making (MCDM) problem and the decision makers with heterogeneous risk preferences. First, from the perspective of objective data, the effective criteria are extracted based on the similarity relations between criterion values and the criteria are weighted, respectively. Second, the corresponding types of theoretic model of risk preferences expectations will be built, based on the possibility and similarity between criterion values to solve the problem for different interval numbers with the same expectation. Then, the risk preferences (Risk-seeking, risk-neutral and risk-aversion) …

Silicon Carbide Based Surface Plasmon Resonance Waveguide Sensor With A Bimetallic Layer For Improved Sensitivity, Wei Du, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

In this letter, silicon carbide (SiC) waveguide-based surface plasmon resonance optical sensor with an Ag-Au bilayer metal configuration was studied. The wide bandgap energy of SiC allows the sensor to operate in visible and near-infrared range. The spectrum of resonant wavelength with refractive index shows improved sensitivity and sensing resolution in the Au-Ag bilayer configuration than in the single Au layer configuration. A sensitivity of 2581 nm/RIU (refractive index unit) indicated by the shift of resonant wavelength with refractive index was observed from a refractive index range of n=1.34–1.36, showing that the sensor is desirable for sensing in a series …

Filamentary Conduction In Aloe Vera Film For Memory Application, Zhe Xi Lim, Sasidharan Sreenivasan, Yew Hoong Wong, Feng Zhao, Kuan Yew Cheong

Electrical and Computer Engineering Faculty Research & Creative Works

Aloe vera gel was extracted, formulated and deposited as thin films by a facile solution process for memory application. The memory cell features a simple structure, in which a dried Aloe vera film was sandwiched in between an Ag top and ITO bottom electrode that was deposited on a glass substrate. Digital information can be encoded and stored as different resistance states of the Aloe vera film. Experimental results reveal that bipolar resistive switching behavior of the Aloe vera film is due to electrochemical growth and dissolution of metallic filaments connecting the top and bottom electrodes. The resistive switching behavior …

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 …

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 Family Of Optimized Lms-Based Algorithms For System Identification, Silviu Ciochinǎ, Constantin Paleologu, Jacob Benesty, Steven L. Grant, Andrei Anghel

Electrical and Computer Engineering Faculty Research & Creative Works

The performance of the least-mean-square (LMS) algorithm is governed by its step-size parameter. In this paper, we present a family of optimized LMS-based algorithms (in terms of the step-size control), in the context of system identification. A time-variant system model is considered, and the optimization criterion is based on the minimization of the system misalignment. Simulations performed in the context of acoustic echo cancellation indicate that these algorithms achieve a proper compromise in terms of fast convergence/tracking and low mis adjustment.