Computer Engineering Commons^™

On Reliability Of Smart Grid Neighborhood Area Networks, Shengjie Xu, Yi Qian, Rose Qingyang Hu

Department of Electrical and Computer Engineering: Faculty Publications

With the integration of the advanced computing and communication technologies, smart grid system is dedicated to enhance the efficiency and the reliability of future power systems greatly through renewable energy resources, as well as distributed communication intelligence and demand response. Along with advanced features of smart grid, the reliability of smart grid communication system emerges to be a critical issue, since millions of smart devices are interconnected through communication networks throughout critical power facilities, which has an immediate and direct impact on the reliability of the entire power infrastructure. In this paper, we present a comprehensive survey of reliability issues …

Spatial Domain Management And Massive Mimo Coordination In 5g Sdn, Songlin Sun, Bo Rong, Rose Qingyang Hu, Yi Qian

Department of Electrical and Computer Engineering: Faculty Publications

In 5G mobile communication systems, massive multiple-input multiple-output (MIMO) and heterogeneous networks (HetNets) play crucial roles to achieve expected coverage and capacity across venues. This paper correspondingly addresses software-defined network (SDN) as the central controller of radio resource management in massive MIMO HetNets. In particular, we identify the huge spatial domain information management and complicated MIMO coordination as the grand challenges in 5G systems. Our work accordingly distinguishes itself by considering more network MIMO aspects, including flexibility and complexity of spatial coordination. In our proposed scheme, SDN controller first collects the user channel state information in an effective way, and …

Skin Effect Suppression In Infrared-Laser Irradiated Planar Multi-Walled Carbon Nanotube/ Cu Conductors, Kamran Keramatnejad, Yang Gao, Yunshen Zhou, Hossein Rabiee Glogir, Mengmeng Wang, Yongfeng Lu

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Skin effect suppression in planar multi-walled carbon nanotube (MWCNT)/Copper (Cu) conductors was realized at the 0-10 MHz frequency range through infrared laser irradiation of MWCNTs, which were coated on the surface of the Cu substrate via the electrophoretic deposition (EPD) method. The effect of laser irradiation and its power density on electrical and structural properties of the MWCNT/Cu conductors was investigated using a wavelength-tunable CO2 laser and then comparing the performance of the samples prepared at different conditions with that of pristine Cu. The irradiation at λ=9.219 μm proved to be effective in selective delivery of energy towards depths close …

Mutations Of Adjacent Amino Acid Pairs Are Not Always Independent, Jyotsna Ramanan, Peter Revesz

CSE Conference and Workshop Papers

Evolutionary studies usually assume that the genetic mutations are independent of each other. This paper tests the independence hypothesis for genetic mutations with regard to protein coding regions. According to the new experimental results the independence assumption generally holds, but there are certain exceptions. In particular, the coding regions that represent two adjacent amino acids seem to change in ways that sometimes deviate significantly from the expected theoretical probability under the independence assumption.

A Computational Translation Of The Phaistos Disk, Peter Revesz

CSE Conference and Workshop Papers

For over a century the text of the Phaistos Disk remained an enigma without a convincing translation. This paper presents a novel semi-automatic translation method that uses for the first time a recently discovered connection between the Phaistos Disk symbols and other ancient scripts, including the Old Hungarian alphabet. The connection between the Phaistos Disk script and the Old Hungarian alphabet suggested the possibility that the Phaistos Disk language may be related to Proto-Finno-Ugric, Proto-Ugric, or Proto-Hungarian. Using words and suffixes from those languages, it is possible to translate the Phaistos Disk text as an ancient sun hymn, possibly connected …

A Computational Model Of The Spread Of Ancient Human Populations Based On Mitochondrial Dna Samples, Peter Revesz

CSE Conference and Workshop Papers

The extraction of mitochondrial DNA (mtDNA) from ancient human population samples provides important data for the reconstruction of population influences, spread and evolution from the Neolithic to the present. This paper presents a mtDNA-based similarity measure between pairs of human populations and a computational model for the evolution of human populations. In a computational experiment, the paper studies the mtDNA information from five Neolithic and Bronze Age populations, namely the Andronovo, the Bell Beaker, the Minoan, the Rössen and the Únětice populations. In the past these populations were identified as separate cultural groups based on geographic location, age and the …

A-Maze-D: Advanced Maze Development Kit Using Constraint Databases, Shruti Daggumarti, Peter Revesz, Corey Svehla

CSE Conference and Workshop Papers

In this paper, we describe the A-Maze-D system which shows that constraint databases can be applied conveniently and efficiently to the design of maze games. A-Maze-D provides a versatile set of features by a combination of a MATLAB library and the MLPQ constraint database system. A-Maze-D is the first system that uses constraint databases to build maze games and opens new ideas in video game development.

A Computational Study Of The Evolution Of Cretan And Related Scripts, Peter Revesz

CSE Conference and Workshop Papers

Crete was the birthplace of several ancient writings, including the Cretan Hieroglyphs, the Linear A and the Linear B scripts. Out of these three only Linear B is deciphered. The sound values of the Cretan Hieroglyph and the Linear A symbols are unknown and attempts to reconstruct them based on Linear B have not been fruitful. In this paper, we compare the ancient Cretan scripts with four other Mediterranean and Black Sea scripts, namely Phoenician, South Arabic, Greek and Old Hungarian. We provide a computational study of the evolution of the three Cretan and four other scripts. This study encompasses …

Coupled Auto-Associative Neural Networks For Heterogeneous Face Recognition, Benjamin S. Riggan, Christopher Reale, Nasser M. Nasrabadi

Department of Electrical and Computer Engineering: Faculty Publications

Several models have been previously suggested for learning correlated representations between source and target modalities. In this paper, we propose a novel coupled autoassociative neural network for learning a target-to-source image representation for heterogenous face recognition. This coupled network is unique, because a cross-modal transformation is learned by forcing the hidden units (latent features) of two neural networks to be as similar as possible, while simultaneously preserving information from the input. The effectiveness of this model is demonstrated using multiple existing heterogeneous face recognition databases. Moreover, the empirical results show that the learned image representation—common latent features—by the coupled auto-associative …

Vcare: A Personal Emergency Response System To Promote Safe And Independent Living Among Elders Staying By Themselves In Community Or Residential Settings, Priyankar Bhattacharjee

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

‘Population aging’ is a growing concern for most of us living in the twenty first century, primarily because many of us in the next few years will have a senior person to care for - spending money towards their healthcare expenditures AND/OR having to balance a full-time job with the responsibility of care-giving, travelling from another city to be with this elderly citizen who might be our parent, grand-parent or even community elders. As informal care-givers, if somehow we were able to monitor the day-to-day activities of our elderly dependents, and be alerted when wrong happens to them that would …

Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

The success of Wireless Sensor Networks is heavily constrained by its reliance on storage technology like batteries, which are a finite resource. Whilst the number of transistors in an IC doubles every 18 months, the energy density of batteries is relatively flat during the same time period. This is a key challenge in leveraging the Internet of Things on trains.

The gravity of this problem is increased by an order of magnitude when the network is to be scaled up to hundreds or thousands of nodes. Comprehensive research and development efforts have been devoted to building ultra-low power sensors. These …

Robust And Real-Time Stereo Matching On Parallel Graphics Hardware Using Gradient-Based Disparity Refinement, Jedrzej Kowalczuk

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Computer vision attempts to provide camera-equipped machines with visual perception, i.e., the capability to comprehend their surroundings through the analysis and understanding of images. The ability to perceive depth is a vital component of visual perception that enables machines to interpret the three-dimensional structure of their surroundings and allows them to navigate through the environment. In computer vision, depth perception is achieved via stereo matching, a process that identifies correspondences between pixels in images acquired using a pair of horizontally offset cameras. It is possible to calculate depths from correspondences or, more specifically, the positional offsets (disparities) between pixels in …

Model-Based Condition Monitoring And Power Management For Rechargeable Electrochemical Batteries, Taesic Kim

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Rechargeable multicell batteries have been used in various electrical and electronic systems, e.g., renewable energy systems, electric-drive vehicles, commercial electronics, etc. However, there are still concerns about the reliability and performance degradation of rechargeable batteries caused by low thermal stability and the aging process. A properly designed battery management system (BMS) is required for condition monitoring and control of multicell batteries to ensure their safety, reliability, and optimal performance. The goal of this dissertation research was to develop a novel BMS for rechargeable multicell batteries.

First, this research developed high-fidelity battery models for online condition monitoring and power management of …

Monolayer And/Or Few-Layer Graphene On Metal Or Metal-Coated Substrates, Peter Werner Sutter, Eli Anguelova Sutter

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is monolayer and/or few-layer graphene on metal or metal-coated substrates. Embodiments include graphene mirrors. In an example, a mirror includes a substrate that has a surface exhibiting a curvature operable to focus an incident beam onto a focal plane. A graphene layer conformally adheres to the substrate, and is operable to protect the substrate surface from degradation due to the incident beam and ambient environment.

Francisella Tularensis Subtype A.Ii Genomic Plasticity In Comparison With Subtype A.I, Marilynn A. Larson, Ufuk Nalbantoglu, Khalid Sayood, Emily B. Zentz, Amanda M. Bartling, Stephen C. Francesconi, Paul D. Fey, Michael P. Dempsey, Steven H. Hinrichs

Department of Electrical and Computer Engineering: Faculty Publications

Although Francisella tularensis is considered a monomorphic intracellular pathogen, molecular genotyping and virulence studies have demonstrated important differences within the tularensis subspecies (type A). To evaluate genetic variation within type A strains, sequencing and assembly of a new subtype A.II genome was achieved for comparison to other completed F. tularensis type A genomes. In contrast with the F. tularensis A.I strains (SCHU S4, FSC198, NE061598, and TI0902), substantial genomic variation was observed between the newly sequenced F. tularensis A.II strain (WY-00W4114) and the only other publically available A.II strain (WY96-3418). Genome differences between WY-00W4114 and WY96- 3418 included three major …

Clustering Header Categories Extracted From Web Tables, George Nagy, David W. Embley, Mukkai Krishnamoorthy, Sharad C. Seth

CSE Conference and Workshop Papers

Revealing related content among heterogeneous web tables is part of our long term objective of formulating queries over multiple sources of information. Two hundred HTML tables from institutional web sites are segmented and each table cell is classified according to the fundamental indexing property of row and column headers. The categories that correspond to the multi-dimensional data cube view of a table are extracted by factoring the (often multi-row/column) headers. To reveal commonalities between tables from diverse sources, the Jaccard distances between pairs of category headers (and also table titles) are computed. We show how about one third of our …

An Isolated Three-Port Bidirectional Dc-Dc Converter For Photovoltaic Systems With Energy Storage, Jianwu Zeng, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a new isolated, three-port, bidirectional, DC-DC converter for simultaneous power management of multiple energy sources. The proposed converter has the advantage of using the least number of switches and soft switching for the main switch, which is realized by using a LCL-resonant circuit. The converter is capable of interfacing sources of different voltage-current characteristics with a load and/or a DC microgrid. The proposed converter is constructed for simultaneous power management of a photovoltaic (PV) panel, a rechargeable battery, and a load. Simulation and experimental results show that the proposed converter is capable of maximum power point tracking …

A Real-Time Information Based Demand-Side Management System In Smart Grid, Feng Ye, Yi Qian, Rose Qingyang Hu

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, we study a real-time information based demand-side management (DSM) system with advanced communication networks in smart grid. DSM can smooth peakto- average ratio (PAR) of power usage in the grid, which in turn reduces the waste of fuel and the emission of greenhouse gas. We first target to minimize PAR with a centralized scheme. To motivate power suppliers, we further propose another centralized scheme targeting minimum power generation cost. However, customers may not be motivated by a centralized scheme since such a scheme requires total control and privacy from them. A centralized scheme also requires too much …

Modeling And Control Of A Three-Port Dc-Dc Converter For Pv-Battery Systems, Jianwu Zeng, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper presents modeling and decoupled control design for an isolated three-port DC-DC converter (TPC), which interfaces a photovoltaic (PV) panel, a rechargeable battery, and an isolated load. A small signal model is derived from the state-space equations of the TPC. Based on the model, two decoupled controllers are designed to control the power flows of the two sources and the load voltage independently. Experimental studies are performed to verify that the two controllers are capable of regulating the power flows of the PV panel and the battery while maintaining a constant output voltage for the TPC.

A Discrete-Time Direct-Torque Control For Direct-Drive Pmsg-Based Wind Energy Conversion Systems, Zhe Zhang, Yue Zhao, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a novel flux space vector-based direct-torque control (DTC) scheme for permanent magnet synchronous generators (PMSGs) used in variable-speed direct drive wind energy conversion systems (WECSs). The discrete time control law, which is derived from the perspective of flux space vectors and load angle, predicts the desired stator flux vector for the next time-step with the torque and stator flux information only. The space-vector modulation (SVM) is then employed to generate the reference voltage vector, leading to a fixed switching frequency as well as lower flux and torque ripples when compared to the conventional DTC. Compared with other …

Femtosecond Laser Induced Tunable Surface Transformations On (111) Si Aided By Square Grids Diffraction, Weina Han, Lan Jiang, Xiaowei Li, Yang Liu, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

We report an extra freedom to modulate the femtosecond laser energy distribution to control the surface ablated structures through a copper-grid mask. Due to the reduced deposited pulse energy by changing the scanning speed or the pulse fluence, a sequential evolution of three distinctly different surface patterns with periodic distributions is formed, namely, striped ripple lines, ripple microdots, and surface modification. By changing the scanning speed, the number of the multiple dots in a lattice can be modulated. Moreover, by exploring the ablation process through the copper grid mask, it shows an abnormal enhanced ablation effect with strong dependence of …

Optimal Joint Transmission And Harvested Energy Scheduling For Renewable Energy Harvesting Enabled Cellular Network Under Coordinated Multi-Point Transmission, Zejue Wang, Hongjia Li, Dan Hu, Song Ci

Department of Electrical and Computer Engineering: Faculty Publications

On-grid energy consumption of base stations (BSs) contributes up a significant fraction of the total carbon dioxide (CO₂) emissions of cellular networks, among which remote radio units (RRUs) absorb most of the energy consumption. To eliminate the on-grid energy consumption and the corresponding CO₂ emission, we propose a new transmission framework, in which all RRUs and associated power amplifiers (PAs) are powered by hybrid energy sources including on-grid energy source and off-grid renewable energy source. Based on the framework, we pursue a systematic study on the joint transmission and harvested energy scheduling algorithm for the hybrid energy …

Modeling,Metrics, And Optimal Design For Solar Energy-Powered Base Station System, Heng Wang, Hongjia Li, Chaowei Tang, Lingbao Ye, Xin Chen, Hui Tang, Song Ci

Department of Electrical and Computer Engineering: Faculty Publications

Using renewable energy system in powering cellular base stations (BSs) has been widely accepted as a promising avenue to reduce and optimize energy consumption and corresponding carbon footprints and operational expenditures for 4G and beyond cellular communications. However, how to design a reliable and economical renewable energy powering (REPing), while guaranteeing communication reliability, renewable energy utilization, and system durability, is still a great challenge. Motivated by this challenge, we firstly model the dynamic energy flow behavior of solar energy-powered BS by using stochastic queue model, jointly considering instability of solar energy generation, non-linear effects of energy storage, and time varies …

Cmi Analysis And Precoding Designs For Correlated Multi-Hop Mimo Channels, Nguyen N. Tran, Song Ci, Ha X. Nguyen

Department of Electrical and Computer Engineering: Faculty Publications

Conditional mutual information (CMI) analysis and precoding design for generally correlated wireless multi-hop multi-input multi-output (MIMO) channels are presented in this paper. Although some particular scenarios have been examined in existing publications, this paper investigates a generally correlated transmission system having spatially correlated channel, mutually correlated source symbols, and additive colored Gaussian noise (ACGN). First, without precoding techniques, we derive the optimized source symbol covariances upon mutual information maximization. Secondly, we apply a precoding technique and then design the precoder in two cases: maximizing the mutual information and minimizing the detection error. Since the optimal design for the end-to-end system …

Leveraging Nanocavity Harmonics For Control Of Optical Processes In 2d Semiconductors, Gleb M. Akselrod, Tian Ming, Christos Argyropoulos, Thang B. Hoang, Yuxuan Lin, Xi Ling, David R. Smith, Jing Kong, Maiken H. Mikkelsen

Department of Electrical and Computer Engineering: Faculty Publications

Optical cavities with multiple tunable resonances have the potential to provide unique electromagnetic environments at two or more distinct wavelengthscritical for control of optical processes such as nonlinear generation, entangled photon generation, or photoluminescence (PL) enhancement. Here, we show a plasmonic nanocavity based on a nanopatch antenna design that has two tunable resonant modes in the visible spectrum separated by 350 nm and with line widths of ∼60 nm. The importance of utilizing two resonances simultaneously is demonstrated by integrating monolayer MoS2, a two-dimensional semiconductor, into the colloidally synthesized nanocavities. We observe a 2000-fold enhancement in the PL intensity of …

Integral Equation Analysis Of Em Scattering From Multilayered Metallic Photonic Crystal Accelerated With Adaptive Cross Approximation, Jianxun Su, Zengrui Li, Xujin Yuan, Yaoqing (Lamar) Yang, Junhong Wang

Department of Electrical and Computer Engineering: Faculty Publications

A space-domain integral equation method accelerated with adaptive cross approximation (ACA) is presented for the fast and accurate analysis of electromagnetic (EM) scattering from multilayered metallic photonic crystal (MPC). The method directly solves for the electric field in order to easily enable the periodic boundary condition (PBC) in the spatial domain. The ACA is a purely algebraic method allowing the compression of fully populated matrices; hence, its formulation and implementation are independent of integral equation kernel (Green’s function).Therefore, the ACA is very well suited for accelerating integral equation analysis of periodic structure with the integral kernel of the periodic Green’s …

Drive Systems Including Sliding Mode Observers And Methods Of Controlling The Same, Long Wu, Yue Zhao, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

At least one example embodiment discloses a drive system including a motor including a rotor, the motor configured to receive a measured current, a controller configured to generate a Voltage command for the motor, a sliding mode observer configured to determine an estimated current for the motor based on the Voltage command, determine a difference between the measured current and the estimated current, and determine a Switching control vector and an estimator con figured to estimate a rotor position based on the Switching control vector, the Switching control vector being determined based on the difference and adaptive parameters of the …

Fiber-Optic Refractometer Based On A Phase-Shifted Fiber Bragg Grating On A Side-Hole Fiber, Qi Zhang, Lingling Hu, Yuefeng Qi, G. Liu, Natale J. Ianno, Ming Han

Department of Electrical and Computer Engineering: Faculty Publications

A fiber-optic refractive index (RI) sensor based on a π-phaseshifted fiber-Bragg-grating (πFBG) inscribed on a side-hole fiber is presented. The reflection spectrum of the πFBG features two narrow notches associated with the two polarization modes and the spectral spacing of the notches is used for high-sensitivity RI sensing with little temperature cross-sensitivity. The side-hole fiber maintains its outer diameter and mechanical strength. The side-hole fiber is also naturally integrated into a microfluidic system for convenient sample delivery and reduced sample amount. A novel demodulation method based on laser frequency modulation to enhance the sensor dynamic range is proposed and demonstrated.

Visualizing Nanoscale Excitonic Relaxation Properties Of Disordered Edges And Grain Boundaries In Monolayer Molybdenum Disulfide, Wei Bao, Nicholas J. Borys, Changhyun Ko, Joonki Suh, Wen Fan, Andrew Thron, Yingjie Zhang, Alexander Buyanin, Jie Zhang, Stefano Cabrini, Paul D. Ashby, Alexander Weber-Bargioni, Sefaattin Tongay, Shaul Aloni, D. Frank Ogletree, Junqiao Wu, Miquel B. Salmeron, P. James Schuck

Department of Electrical and Computer Engineering: Faculty Publications

Two-dimensional monolayer transition metal dichalcogenide semiconductors are ideal building blocks for atomically thin, flexible optoelectronic and catalytic devices. Although challenging for two-dimensional systems, sub-diffraction optical microscopy provides a nanoscale material understanding that is vital for optimizing their optoelectronic properties. Here we use the ‘Campanile’ nano-optical probe to spectroscopically image exciton recombination within monolayer MoS2 with sub-wavelength resolution (60 nm), at the length scale relevant to many critical optoelectronic processes. Synthetic monolayer MoS2 is found to be composed of two distinct optoelectronic regions: an interior, locally ordered but mesoscopically heterogeneous two-dimensional quantum well and an unexpected B300-nm wide, energetically disordered edge …

Probes For Multidimensional Nanospectroscopic Imaging And Methods Of Fabrication Thereof, Alexander Weber-Bargionii, Stefano Cabrini, Wei Bao, Mauro Melli, Eli Yablonovitch, Peter J. Schuck

Department of Electrical and Computer Engineering: Faculty Publications

This disclosure provides systems, methods, and apparatus related to probes for multidimenisonal nanospectroscopic imaging. In one aspect, a method includes providing a transparent tip comprising a dielectric material. A four-sided pyramidal-shaped structure is formed at an apex of the transparent tip using a focus ion beam. Metal layers are deposited over two opposing sides of the four-sided pyramidal-shaped structure.