Digital Commons Network^™

A Uniform Strain Transfer Scheme For Accurate Distributed Optical Fiber Strain Measurements In Civil Structures, Yang Du, Yizheng Chen, Yiyang Zhuang, Chen Zhu, Rex E. Gerald Ii, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

We report a screw-like package design for an embeddable distributed optical fiber strain sensor for civil engineering applications. The screw-like structure is the exterior support for an optical fiber sensor. The bare optical fiber is embedded and secured in a longitudinal groove of the screw-like package using a rigid adhesive. Our packaging scheme prevents damage to the bare optical fiber and ensures that the packaged sensor is accurately and optimally sensing strain fields in civil structures. Moreover, our screw-like design has an equal area in a cross-section perpendicular to and along the screw axis, so strain field distributions are metered …

Half-Mode Cavity-Based Planar Filtering Antenna With Controllable Transmission Zeroes, Kirti Dhwaj, Joshua M. Kovitz, Haozhan Tian, Li (Lijun) Jun Jiang, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

Atwo-pole half-mode substrate integrated waveguide (HMSIW) cavity-based filtering antenna is presented. The HMSIW cavity is used as a radiating resonator with a conventional substrate integrated waveguide (SIW) cavity functioning as a high- Q resonator of the filter, leading to its compact size. The concept of source-load coupling is introduced for filtering antennas, which allows for the presence of two controllable transmission zeroes (TZs) in the frequency response of proposed design. This is accomplished by using electric coupling between two resonator cavities and a combination of microstrip/coaxial line to feed the antenna. The single-layer printed circuit board structure provides a broadside …

Direct Error Driven Learning For Deep Neural Networks With Applications To Bigdata, R. Krishnan, Jagannathan Sarangapani, V. A. Samaranayake

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, generalization error for traditional learning regimes-based classification is demonstrated to increase in the presence of bigdata challenges such as noise and heterogeneity. To reduce this error while mitigating vanishing gradients, a deep neural network (NN)-based framework with a direct error-driven learning scheme is proposed. To reduce the impact of heterogeneity, an overall cost comprised of the learning error and approximate generalization error is defined where two NNs are utilized to estimate the costs respectively. To mitigate the issue of vanishing gradients, a direct error-driven learning regime is proposed where the error is directly utilized for learning. It …

Equivalent Capacitance Approach To Calculate Effective Roughness Dielectric Parameters For Copper Foils On Printed Circuit Boards, Marina Y. Koledintseva, Tracey Vincent

Electrical and Computer Engineering Faculty Research & Creative Works

Effective roughness dielectric (ERD) is a homogeneous lossy dielectric layer of certain thickness with effective (averaged) dielectric parameters. The ERD layer is used to model copper foil roughness in printed circuit board interconnects by being placed on a smooth conductor surface to substitute an inhomogeneous transition layer between a conductor and laminate substrate dielectric. This work derives the ERD parameters based on the understanding that there is a gradual variation of concentration of metallic inclusions in the transition layer between the dielectric and foil. The gradual variation can be structured as thin layers that are obtained using the equivalent capacitance …

A Hollow Coaxial Cable Fabry-Perot Resonator For Liquid Dielectric Constant Measurement, Chen Zhu, Yiyang Zhuang, Yizheng Chen, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

We report, for the first time, a low-cost and robust homemade hollow coaxial cable Fabry-Pérot resonator (HCC-FPR) for measuring liquid dielectric constant. In the HCC design, the traditional dielectric insulating layer is replaced by air. A metal disk is welded onto the end of the HCC serving as a highly reflective reflector, and an open cavity is engineered on the HCC. After the open cavity is filled with the liquid analyte (e.g., water), the air-liquid interface acts as a highly reflective reflector due to large impedance mismatch. As a result, an HCC-FPR is formed by the two highly reflective reflectors, …

Displacement And Strain Measurement Up To 1000 °C Using A Hollow Coaxial Cable Fabry-Perot Resonator, Chen Zhu, Yizheng Chen, Yiyang Zhuang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

We present a hollow coaxial cable Fabry-Perot resonator for displacement and strain measurement up to 1000 °C. By employing a novel homemade hollow coaxial cable made of stainless steel as a sensing platform, the high-temperature tolerance of the sensor is dramatically improved. A Fabry-Perot resonator is implemented on this hollow coaxial cable by introducing two highly-reflective reflectors along the cable. Based on a nested structure design, the external displacement and strain can be directly correlated to the cavity length of the resonator. By tracking the shift of the amplitude reflection spectrum of the microwave resonator, the applied displacement and strain …

An Embeddable Strain Sensor With 30 Nano-Strain Resolution Based On Optical Interferometry, Chen Zhu, Yizheng Chen, Yiyang Zhuang, Fujian Tang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

A cost-effective, robust and embeddable optical interferometric strain sensor with nanoscale strain resolution is presented in this paper. The sensor consists of an optical fiber, a quartz rod with one end coated with a thin gold layer, and two metal shells employed to transfer the strain and orient and protect the optical fiber and the quartz rod. The optical fiber endface, combining with the gold-coated surface, forms an extrinsic Fabry—Perot interferometer. The sensor was firstly calibrated, and the result showed that our prototype sensor could provide a measurement resolution of 30 nano-strain (nε) and a sensitivity of 10.01 µε/ µm …

A Straightforward Updating Criterion For 2-D/3-D Hybrid Discontinuous Galerkin Time-Domain Method Controlling Comparative Error, Wending Mai, Ping Li, C. G. Li, Ming Jiang, Wenqu Hao, Lijun Jiang, Jun Hu

Electrical and Computer Engineering Faculty Research & Creative Works

The 2-D/3-D hybrid discontinuous Galerkin time-domain (DGTD) method is efficient to deal with structures that contain elements capable of 2-D simplification. To separate 2-D elements from 3-D ones, a criterion for approximation error manipulation is required. However, in the latest reported technique, this kind of criterion is derived from the causality principle and the Courant-Freidrichs-Lewy constraint, and thus is indirect and inessential to 2-D simplification. As a result, some elements capable of 2-D simplification are unnecessarily flagged as 3-D ones, deteriorating efficiency dramatically. Moreover, controlling absolute error, the traditional criterion is not flexible for structures with complex mode distribution. In …

A Novel Deep Junction Edge Termination For Superjunction Mosfets, Chia Hui Cheng, Chih Fang Huang, Kung Yen Lee, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

In this letter, a novel edge termination named deep junction termination for silicon super junction (SJ) MOSFETs is proposed, simulated, and experimentally demonstrated for the first time. By utilizing a typical implantation-and-epitaxy process to form P- and N-pillars for SJ, it is possible to form deep junctions as the device termination with a large radius of curvature and lateral and vertical doping gradation. The 2-D simulation shows that more than 700-V blocking voltage (BV) can be achieved by a 57-drift layer with this novel termination, and experimentally BV as high as 660 V is demonstrated by the fabricated device.

High Voltage Gain Dc/Dc Power Electronic Converters, Mehdi Ferdowsi, Venkata Anand Kishore Prabhala

Electrical and Computer Engineering Faculty Research & Creative Works

A DC/DC power converter provides high voltage gain using integrated boost and voltage multiplier (VM) stages. The boost cell operates according to a switching sequence to alternately energize and discharge a primary winding. A VM cell electrically coupled to the primary winding of the boost cell charges a multiplier capacitor to a DC output voltage greater than the input voltage when the primary winding is energized and discharges the multiplier capacitor when primary winding is discharged.

Electrically Tunable Polarizer Based On Graphene-Loaded Plasmonic Cross Antenna, Yuwei Qin, Xiaoyan Y.Z. Xiong, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The unique gate-voltage dependent optical properties of graphene make it a promising electrically tunable plasmonic material. In this work, we proposed in situ control of the polarization of nanoantennas by combining plasmonic structures with an electrostatically tunable graphene monolayer. The tunable polarizer is designed based on an asymmetric cross nanoantenna comprising two orthogonal metallic dipoles sharing the same feed gap. Graphene monolayer is deposited on a Si/SiO2 substrate and inserted beneath the nanoantenna. Our modelling demonstrates that as the chemical potential is incremented up to 1 eV by electrostatic doping, resonant wavelength for the longer graphene-loaded dipole is blue shifted …

Orbital Angular Momentum Generation And Detection By Geometric-Phase Based Metasurfaces, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

We present a comprehensive review on the geometric phase based metasurfaces for orbital angular momentum (OAM) generation and detection. Thesemetasurfacesmanipulate the electromagnetic (EM) wave by introducing abrupt phase change, which is strongly dependent on the polarization state of incident EMwave and can be interpreted by geometric phase. Hence, the conventional bulk devices that based on the accumulated phase change along the optical path can be avoided.

Deep Learning Nuclei Detection In Digitized Histology Images By Superpixels, Sudhir Sornapudi, R. Joe Stanley, William V. Stoecker, Haidar Almubarak, Rodney Long, Sameer Antani, George Thoma, Rosemary Zuna, Shelliane R. Frazier

Electrical and Computer Engineering Faculty Research & Creative Works

Background: Advances in image analysis and computational techniques have facilitated automatic detection of critical features in histopathology images. Detection of nuclei is critical for squamous epithelium cervical intraepithelial neoplasia (CIN) classification into normal, CIN1, CIN2, and CIN3 grades.

Methods: In this study, a deep learning (DL)-based nuclei segmentation approach is investigated based on gathering localized information through the generation of superpixels using a simple linear iterative clustering algorithm and training with a convolutional neural network.

Results: The proposed approach was evaluated on a dataset of 133 digitized histology images and achieved an overall nuclei detection (object-based) accuracy of 95.97%, with …

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 model is proposed, where the legitimate transmitter and receiver communicate over a discrete memoryless channel. The wiretapper has perfect access to a fixed-length subset of the transmitted code word symbols of her choosing. Additionally, she observes the remainder of the transmitted symbols through a discrete memoryless channel. This new model subsumes the classical wiretap channel and wiretap channel II with noisy main channel as its special cases and is termed as the generalized wiretap channel for that reason. The strong secrecy capacity of the proposed channel model is identified. Achievability is established by …

Camks Support Development Of Acute Myeloid Leukemia, Xunlei Kang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Background: We recently identified the human leukocyte immunoglobulin-like receptor B2 (LILRB2) and its mouse ortholog-paired Ig-like receptor (PirB) as receptors for several angiopoietin-like proteins (Angptls). We also demonstrated that PirB is important for the development of acute myeloid leukemia (AML), but exactly how an inhibitory receptor such as PirB can support cancer development is intriguing. Results: Here, we showed that the activation of Ca (2+)/calmodulin-dependent protein kinases (CAMKs) is coupled with PirB signaling in AML cells. High expression of CAMKs is associated with a poor overall survival probability in patients with AML. Knockdown of CAMKI or CAMKIV decreased human acute …

Probing Changes In Tilt Angle With 20 Nanoradian Resolution Using An Extrinsic Fabry-Perot Interferometer-Based Optical Fiber Inclinometer, Yiyang Zhuang, Yizheng Chen, Chen Zhu, Rex E. Gerald Ii, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we introduce and demonstrate a novel optical fiber extrinsic Fabry-Perot interferometer (EFPI) for tilt measurements with 20 nrad resolution. Compared with inline optical fiber inclinometers, an extrinsic sensing structure is used in the inclinometer reported herein. Our design greatly improves on the tilt angle resolution, the temperature stability, and the mechanical robustness of inclinometers with advanced designs. An EFPI cavity, which is formed between endfaces of a suspended rectangular mass block and a fixed optical fiber, is packaged inside a rectangular container box with an oscillation dampening mechanism. Importantly, the two reflectors of the EFPI sensor remain …

Fast Direct Equivalence Principle Algorithm For Multi-Scale Electromagnetic Problems, Qin S. Liu, Qi Dai, Tian Xia, Ting Wan, Li (Lijun) Jun Jiang, Sheng Sun, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

The Equivalence principle algorithm is proposed to integrated with hierarchical matrix based fast direct solver in order to solve deep multi-scale problem accurately and efficiently. Additionally, model order reduction techniques are applied to the equivalence principle algorithm to further reduce the computational complexities.

Machine Learning Based Multilevel Fast Multipole Algorithm, Jia Jing Sun, Sheng Sun, Yongpin Chen, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel translator calculation method for the multilevel fast multipole algorithm (MLFMA) is proposed based on a machine learning approach. The generalized regression neural networks are introduced to fit the translation function of MLFMA during the procedure of eletromagnetic scattering analysis. Compared to the traditional method, the new method inherits advantages of the generalized regression neural networks (GRNN) and can approximate the translator with high accuracy simultaneously. As an example, a two-level 2D MLFMA for a perfect electrically conductor (PEC) is finally implemented and the translators are reconstructed by using the proposed model. The numerical results validate …

Outsmart Moore’S Law With Machine Learning, Dustin Tanksley, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Over the last half century, computing has transformed most aspects of society due to a rapid increase in computation power. With the possible end of Moore’s Law in sight, much of this growth could come to an end. This paper will discuss why machine learning will continue growing even after Moore’s Law, and demonstrate why it is a great time to enter the field.

Investigation Of High Indium-Composition Ingan/Gan Heterostructures On Zno Grown By Metallic Organic Chemical Vapor Deposition, M. Tian, Y. D. Qian, C. Zhang, L. Li, S. D. Yao, I. T. Ferguson, D. N. Talwar, J. Y. Zhai, D. H. Meng, K. Y. He, L. Y. Wan, Z. C. Feng

Electrical and Computer Engineering Faculty Research & Creative Works

The optical properties and film quality for a series of high-In composition InGaN films grown on ZnO substrate by metal-organic chemical vapor deposition (MOCVD) are characterized by using high resolution X-ray diffraction (HRXRD), Rutherford backscattering (RBS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and Raman scattering spectroscopy (RSS). The In composition is evaluated by analyzing the RBS and PL emission spectra. The XPS measurements revealed the diffusion of Zn atoms from the substrate into InGaN films. All the analyses of experimental measurements have shown that the growth temperature played an important role in indium composition as well as of film quality. …

Detection Of Orbital Angular Momentum With Metasurface At Microwave Band, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

An orbital angular momentum (OAM) detection approach at microwave band is proposed. A transmittance function is exploited to model a transmissive metasurface. Then, the metasurface is designed to convert an OAM wave to multiple waves, only one of which is Gaussian. The radiation direction of the Gaussian wave is distinguishable according to the order of incident OAM. Consequently, by locating the Gaussian wave, the incident OAM can be conveniently determined. We use a simple field source to simulate the incident OAM wave in full-wave simulation. It largely simplifies the simulation process when an incident wave carrying OAM is needed. Both …

Room Temperature Ferromagnetism In Gadolinium-Doped Gallium Nitride, Vishal G. Saravade, Cameron H. Ferguson, Amirhossein Ghods, Chuanle Zhou, Ian T. Ferguson

Electrical and Computer Engineering Faculty Research & Creative Works

Anomalous Hall effect was observed at room temperature in MOCVD-grown GaGdN from a (TMHD)3Gd source, which can contain oxygen in its organic ligand. GaN, and GaGdN grown using a Cp3Gd precursor which does not contain oxygen only showed the ordinary Hall effect. This indicates that oxygen could have a role in magnetic properties of GaGdN. The relationship between the anomalous Hall conductivity and longitudinal conductivity indicated that metallic conduction, hopping of carriers, and scattering-independent mechanisms are likely responsible for the ferromagnetism. However, this still requires further clarification.

Synchrotron Radiation X-Ray Absorption Spectroscopy And Spectroscopic Ellipsometry Studies Of Insb Thin Films On Gaas Grown By Metalorganic Chemical Vapor Deposition, Yingda Qian, Yuanlan Liang, Xuguang Luo, Kaiyan He, Wenhong Sun, Hao Hsiung Lin, Devki N. Talwar, Ting Shan Chan, Ian Ferguson, Lingyu Wan, Qingyi Yang, Zhe Chuan Feng

Electrical and Computer Engineering Faculty Research & Creative Works

A series of ultrathin InSb films grown on GaAs by low-pressure metalorganic chemical vapor deposition with different V/III ratios were investigated thoroughly using spectroscopic ellipsometry (SE), X-ray diffraction, and synchrotron radiation X-ray absorption spectroscopy. The results predicted that InSb films on GaAs grown under too high or too low V/III ratios are with poor quality, while those grown with proper V/III ratios of 4.20-4.78 possess the high crystalline quality. The temperature-dependent SE (20-300°C) and simulation showed smooth variations of SE spectra, optical constants (n, k, e1, and ϵ2), and critical energy points (E1, E1+Δ1, E′0, E2, and E′1) for InSb …

Containment Control Of Heterogeneous Systems With Non-Autonomous Leaders: A Distributed Optimal Model Reference Approach, Yongliang Yang, Shusen Cheng, Yixin Yin, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a distributed optimal model reference adaptive control approach for solving containment control of heterogeneous multi-agent systems (MASs) with non-autonomous leaders. First, a fully distributed adaptive observer is designed to provide for each agent the desired reference trajectory by estimating the convex hull spanned by leaders. The distributed observer dynamics serves as a reference model for each follower to synchronize. The global communication graph information or the leader dynamics is not required to design the observer. In contrast to existing model reference adaptive controllers (MRAC) for single-agent systems and containment control solutions for MASs, the proposed MRAC approach …

Ferrite Assisted Geometry-Conformal Magnetic Induction Antenna And Subsea Communications For Auvs, Debing Wei, Li Yan, Xuanheng Li, Jie Wang, Jiefu Chen, Miao Pan, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper designs a novel geometry-conformal antenna for Magnetic Induction (MI)-based subsea wireless communications for autonomous underwater vehicles (AUV). The designed tri-directional antennas can be wrapped directly on the surface of AUVs, such that the AUVs fluid dynamics are well maintained to ensure power efficiency of the vehicles. In addition, ferrite materials are added between the MI antenna and the metallic body surface of the AUVs to overcome the shielding effect and enhance the MI signal strength. The designed MI communication system is implemented in hardware and the effectiveness of the geometry-conformal MI antenna is demonstrated through COMSOL simulations and …

Machine Learning Based Neural Network Solving Methods For The Fdtd Method, He Ming Yao, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, two novel computational processes are proposed to solve Finite-Difference Time-Domain (FDTD) based on machine learning deep neural networks. The field and boundary conditions are employed to establish recurrent neural network FDTD (RNN-FDTD) model and convolution neural network FDTD (CNN-FDTD) model respectively. Numerical examples from scalar wave equations are provided to benchmark the performance of the proposed methods. The results demonstrate that the newly proposed methods could solve FDTD steps with satisfactory accuracy. According to our knowledge, these are unreported new approaches for machine learning based FDTD solving methods.

Applying Convolutional Neural Networks For The Source Reconstruction, He Ming Yao, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel source reconstruction method (SRM) based on the convolutional neural network algorithm. The conventional SRM method usually requires the scattered field data oversampled compared to that of target object grids. To achieve higher accuracy, the conventional SRM numerical system is highly singular. To overcome these difficulties, we model the equivalent source reconstruction process using the machine learning. The equivalent sources of the target are constructed by a convolutional neural networks (ConvNets). It allows us to employ less scattered field samples or radar cross section (RCS) data. And the ill-conditioned numerical system is effectively avoided. Numerical examples …

Application-Adaptable Chipless Rfid Tag, Katelyn Brinker, Reza Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Chipless RFID has gained prominence due to its application versatility and cost and complexity advantages over traditional RFID. However, chipless RFID tags are typically designed for a specific application instead of being deployable for a multitude of applications. In this paper, a new approach to adaptable chipless RFID tag is proposed that can be optimized for a variety of applications, including materials characterization with tags as embedded sensors. Additionally, the designed approach renders tags that can be interrogated with a linearly polarized probe and achieves bit densities up to 27.57 bits/cm 2,

Inorganic Biodegradable Substrates For Devices And Systems, Chang-Soo Kim, Richard K. Brow, D. E. Day

Electrical and Computer Engineering Faculty Research & Creative Works

Disclosed are biodegradable glass substrates that are useful as functional elements of solid-state devices. In particular, biodegradable glass substrates having a rapidly degradable glass and a slowly degradable glass provide a structural platform that completely dissolves following a desired operational lifetime of devices such as implanted electronic devices, implanted sensor devices, and optical fibers.

An Analysis Of Scattering From Snow With Relaxed Hierachical Equivalent Source Algorithm, Chan Fai Lum, Hong Tat Ewe, Fu Xin, Li (Lijun) Jun Jiang, Hean Teik Chuah

Electrical and Computer Engineering Faculty Research & Creative Works

Traditionally, Radiative Transfer (RT) formulation has been used to simulate scattering from snow layer with the incorporation of phase matrix of scatterers in the formulation. Typically, spherical scatterers were assumed to represent the ice particles embedded inside the air medium and Mie phase matrix was applied. However, the real scatterers in the actual snow are generally more irregular than the assumed spherical shape. In this paper, a numerical solution based on the Hierarchical Equivalent Source Algorithm (HESA) has been developed to calculate the phase matrix of scatterers of other shapes to be incorporated in the existing RT formulation. Results from …