Electrical and Computer Engineering Commons^™

Designing A Halbach Rotor Magnetic Gear For A Marine Hydrokinetic Generator, Hossein Baninajar, Sina Modaresahmadi, H. Y. Wong, Jonathan Bird, W. Williams, B. Dechant

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents the electromagnetic and mechanical design as well as experimental testing results for a 9.5:1 gear ratio, series connected, coaxial magnetic gear (MG) for use in a marine hydrokinetic generator. A 2-D and 3-D magnetostatic finite element analysis (FEA) sizing analysis was also conducted and a torque density comparison between using a nested or series MG typology is presented. To achieve a high torque density a four-segment per pole-pair Halbach rotor assembly with a unique slotted Halbach magnet arrangement was used that enables the Halbach rotor magnets to be more easily assembled, even with dimensional tolerance inaccuracies. A …

Experimental Validation Of A Reflective Long Period Grating Design Methodology, Sohel Rana, Nirmala Kandadai, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

In this work, we present an experimental demonstration of our previously published modeling work on reflective long period grating (LPG). To provide the practical realization of the modeling work, we coat a long segment of fiber both in the tail length and the end facet beyond the gratings with silver to invert the transmission mode LPG to reflection mode LPG. We then measure the LPG characteristics in both the transmission and reflection mode and validate our findings from modeling work. We further build temperature and refractive index (RI) sensors and demonstrate temperature sensing from 21 °C to 191 °C with …

Proposed Application For An Entity Component System In An Energy Services Interface, Tylor Slay, Grace B. Spitzer, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

An Entity Component System is a data-oriented architecture originally developed to streamline video game performance. Despite being quite new, Entity Component Systems are relatively well established within the video game industry due to the cutting edge nature of research into performance, especially around graphics. However, Entity Component Systems have not been widely examined or adopted outside of that industry. We propose adopting an Entity Component Systems framework to serve the needs of an Energy Service Interfaces. We examine the needs of an Energy Service Interface, give an overview of open-source Entity Component Systems (ECSs) libraries, examine some preliminary performance results …

Poster: K-Anonymity Applied To The Energy Grid Of Things Distributed Energy Resource Management System, Mohammed Alsaid, Tylor Slay, Nirupama Bulusu, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

The violation of information privacy in Smart Grids can be a significant barrier to customers’ participation. Employing privacy protection models such as K-anonymity in a Smart Grid implementation adds desirable privacy guarantees. This work provides an approach to applying the Mondrian algorithm to ensure data within the system excludes Personally Identifiable Information. Results suggest that a dynamically generated generalization hierarchy minimizes information loss incurred by the anonymization process.

Real-Time Measurement Of Parametric Influences On The Refractive Index And Length Changes In Silica Optical Fibers, Sohel Rana, Austin Fleming, Harish Subbaraman, Nirmala Kandadai

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper, we present a simple cascaded Fabry-Perot interferometer (FPI) that can be used to measure in real-time the refractive index (RI) and length variation in silica optical fibers caused due to external physical parameters, such as temperature, strain, and radiation. As a proof-of-concept, we experimentally demonstrate real-time monitoring of temperature effects on the RI and length and measure the thermo-optic coefficient (TOC) and thermal expansion coefficient (TEC) by using the cascaded FPI within a temperature range of 21–486°C. The experimental results provide a TEC of 5.53 × 10⁻⁷ /°C and TOC of 4.28 × 10⁻⁶ /°C …

Privacy-Preserving Information Security For The Energy Grid Of Things, Mohammed Alsaid, Nirupama Bulusu, Abdullah Barghouti, N. Sonali Fernando, John M. Acken, Tylor E. Slay, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Smart grid infrastructure relies on information exchange between multiple actors in order to ensure system reliability. These actors include but are not limited to smart loads, grid control, and energy management technologies. As information exchange between these actors is susceptible to cyber-attacks, security and privacy issues are indispensable to ensure a reliable and stable grid. This position paper proposes a privacy-preserving, trust-augmented secure scheme for a smart grid implementation.

A Deep Unsupervised Feature Learning Spiking Neural Network With Binarized Classification Layers For The Emnist Classification, Ruthvik Vaila, John Chiasson, Vishal Saxena

Electrical and Computer Engineering Faculty Publications and Presentations

End user AI is trained on large server farms with data collected from the users. With ever increasing demand for IoT devices, there is a need for deep learning approaches that can be implemented at the Edge in an energy efficient manner. In this work we approach this using spiking neural networks. The unsupervised learning technique of spike timing dependent plasticity (STDP) and binary activations are used to extract features from spiking input data. Gradient descent (backpropagation) is used only on the output layer to perform training for classification. The accuracies obtained for the balanced EMNIST data set compare favorably …

A Synergic Quantum Particle Swarm Optimisation For Constrained Combinatorial Test Generation, Xu Guo, Xiaoyu Song, Jian-Tao Zhou

Electrical and Computer Engineering Faculty Publications and Presentations

Combinatorial testing (CT) can efficiently detect failures caused by interactions of parameters of software under test. The CT study has undergone a transition from traditional CT to constrained CT, which is crucial for real-world systems testing. Under this scenario, constrained covering array generation (CCAG), a vital combinatorial optimisation issue targeted with constructing a test suite of minimal size while properly addressing constraints, remains challenging in CT. To the authors’ best knowledge, this paper presents a synergic method first based on quantum particle swarm optimisation (QPSO) for the CCAG problems. Three auxiliary strategies, including contraction-expansion coefficient adaptive change strategy, differential evolution …

Inertial Sensor Algorithm To Estimate Walk Distance, Vrutangkumar Shah, Carolin Curtze, Kristen Sowalsky, Ishu Arpan, Martina Mancini, James Mcnames, Mahmoud El-Gohary, Fay Horak, Patricia Carlson-Kuhta

Electrical and Computer Engineering Faculty Publications and Presentations

The “total distance walked” obtained during a standardized walking test is an integral component of physical fitness and health status tracking in a range of consumer and clinical applications. Wearable inertial sensors offer the advantages of providing accurate, objective, and reliable measures of gait while streamlining walk test administration. The aim of this study was to develop an inertial sensor-based algorithm to estimate the total distance walked using older subjects with impaired fasting glucose (Study I), and to test the generalizability of the proposed algorithm in patients with Multiple Sclerosis (Study II). All subjects wore two inertial sensors (Opals by …

Hamilton’S Geoacoustic Model, Charles W. Holland, Stan E. Dosso

Electrical and Computer Engineering Faculty Publications and Presentations

Hamilton’s classic 1980 paper² formulated the modern concept of a seabed geoacoustic model, drawing on extensive literature to com- pile and synthesize information on seabed properties. Hamilton defined a geoacoustic model as a “model of the real seafloor with emphasis on measured, extrapolated, and predicted values of those properties important in underwater acoustics” that includes “the true thicknesses and properties of sediment and rock layers.” His work provided both the framework for predicting geoacoustic properties and the data to support it.

Hamilton complied geoacoustic information from diverse sources, including laboratory measurements, in situ probes, samples and cores, echo-sounder records, …

Effect Of Room Air Exposure On The Field Emission Performance Of Uv Light Irradiated Si-Gated Field Emitter Arrays, Ranajoy Bhattacharya, Mason Cannon, Rushmita Bhattacharjee, Jim Browning

Electrical and Computer Engineering Faculty Publications and Presentations

Field emission cathodes are promising candidates in nanoscale vacuum channel transistors and are used in microwave vacuum electron devices. Prior research has shown that UV light exposure as well as 350 °C vacuum bake can desorb water vapor from Si field emission tips, resulting in lower work function and improved emission performance. However, after long exposure to room air (greater than 24 h), the improved performance is lost as water adsorbs on the tips. In this study, experiments were carried on two sets of 1000 × 1000 Si-gated field emitter arrays to determine the length of time that emitters can …

Handwritten English Word Recognition Using A Deep Learning Based Object Detection Architecture, Riktim Mondal, Samir Malakar, Elisa H. Barney Smith, Ram Sarkar

Electrical and Computer Engineering Faculty Publications and Presentations

Handwriting is used to distribute information among people. To access this information for further analysis the page needs to be optically scanned and converted to machine recognizable form. Due to unconstrained writing styles along with connected and overlapping characters, handwriting recognition remains a challenging task. Most of the methods in the literature use lexicon-based approaches and train their models on large datasets having near 50 K word samples to achieve good results. This results in high computational requirements. While these models use around 50 K words in their dictionary when recognizing handwritten English text, the actual number of words in …

Future Needs Of The Cybersecurity Workforce, Connie Justice, Char Sample, Sin Ming Loo, Alex Ball, Clay Hampton

Electrical and Computer Engineering Faculty Publications and Presentations

Expected growth of the job market for cyber security professionals in both the US and the UK remains strong for the foreseeable future. While there are many roles to be found in cyber security, that vary from penetration tester to chief information security officer (CISO). One job of particular interest is security architect. The rise in Zero Trust Architecture (ZTA) implementations, especially in the cloud environment, promises an increase in the demand for these security professionals. A security architect requires a set of knowledge, skills, and abilities covering the responsibility for integrating the various security components to successfully support an …

A Graph-Based Approach To Boundary Estimation With Mobile Sensors, Sean Onufer Stalley, Dingyu Wang, Gautam Dasarathy, John Lipor

Electrical and Computer Engineering Faculty Publications and Presentations

We consider the problem of adaptive sampling for boundary estimation, where the goal is to identify the two dimensional spatial extent of a phenomenon of interest. Motivated by applications in estimating the spread of wildfires with a mobile sensor, we present a novel graph-based algorithm that is efficient in both the number of samples taken and the distance traveled. The key idea behind our approach is that by sampling locations close to known cut edges (edges whose vertices lie on opposite sides of the boundary), we can reliably find additional cut edges. Our approach repeats this process of using the …

Incentivizing Distributed Energy Resource Participation In Grid Services, Tylor Slay, John M. Acken, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

The bulk power system is experiencing a dramatic shift as renewable generation growth continues to accelerate. Large-scale renewables adoption will help societies transition to a low-carbon, low-cost, and environmental-friendly electrical power system. However, the transition from a paradigm of generation following load to one where load follows generation will require large-scale interconnection and coordinated operation of Distributed Energy Resources (DERs), supported by open communication protocols. In this future grid scenario, DER aggregations will provide critical grid services that enable high penetration levels of renewable generation. This position paper presents an Energy Service Interface (ESI) that defines scope for ensuring secure, …

A Field Test Of Direct Load Control Of Water Heaters And Its Implications For Consumers, Midrar Adham, Manasseh Obi, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Utilities and customers are now operating more closely than ever. The prevailing numbers of grid-interactive Distributed Energy Resources are being integrated to provide grid reliability and stability. Different methods of control have been implemented to utilize these Distributed Energy Resources, such as Service-Oriented Load Control and Direct Load Control. This paper investigates the issues associated with the latter. A Direct Load Control method is applied to two Distributed Energy Resources, Electric Water Heater and Heat Pump Water Heater. A load shifting scenario is created where each water heater turns off during water draw events that coincide with peak demand periods. …

A Means For Tuning Primary Frequency Event Detection Algorithms, Sean Keene, Landon Hanks, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Power system balancing authorities are routinely affected by sudden frequency fluctuations. These frequency events can precipitate cascading outages and cause damage to both customer-owned and utility equipment. In this document, we describe an Algorithm Evaluation Environment that uses a suite of metrics to evaluate an algorithm and quantify its efficacy. Using the Algorithm Evaluation Environment, a detection algorithm can be tuned to best match the definition of a frequency event as defined by experts within the context of their own balancing area. We demonstrate the utility of the Algorithm Evaluation Environment using a regression-based frequency event detection algorithm. This algorithm …

Exciton Delocalization And Scaffold Stability In Bridged Nucleotide-Substituted, Dna Duplex-Templated Cyanine Aggregates, Simon K. Roy, Olga A. Mass, Donald L. Kellis, Christopher K. Wilson, John A. Hall, Bernard Yurke, William B. Knowlton

Electrical and Computer Engineering Faculty Publications and Presentations

Molecular excitons play a foundational role in chromophore aggregates found in light-harvesting systems and offer potential applications in engineered excitonic systems. Controlled aggregation of chromophores to promote exciton delocalization has been achieved by covalently tethering chromophores to deoxyribonucleic acid (DNA) scaffolds. Although many studies have documented changes in the optical properties of chromophores upon aggregation using DNA scaffolds, more limited work has investigated how structural modifications of DNA via bridged nucleotides and chromophore covalent attachment impact scaffold stability as well as the configuration and optical behavior of attached aggregates. Here we investigated the impact of two types of bridged nucleotides, …

Active Compensation Of Radiation Effects On Optical Fibers For Sensing Applications, Sohel Rana, Austin Fleming, Nirmala Kandadai, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

Neutron and gamma irradiation is known to compact silica, resulting in macroscopic changes in refractive index (RI) and geometric structure. The change in RI and linear compaction in a radiation environment is caused by three well-known mechanisms: (i) radiation-induced attenuation (RIA), (ii) radiation-induced compaction (RIC), and (iii) radiation-induced emission (RIE). These macroscopic changes induce errors in monitoring physical parameters such as temperature, pressure, and strain in optical fiber-based sensors, which limit their application in radiation environments. We present a cascaded Fabry–Perot interferometer (FPI) technique to measure macroscopic properties, such as radiation-induced change in RI and length compaction in real time …

A Multi-Dimensional Child-Langmuir Law For Any Diode Geometry, N. R. Sree Harsha, Marcus Pearlman, Jim Browning, Allen L. Garner

Electrical and Computer Engineering Faculty Publications and Presentations

While prior theoretical studies of multi-dimensional space-charge limited current (SCLC) assumed emission from a small patch on infinite electrodes, none have considered emission from an entire finite electrode. In this paper, we apply variational calculus (VC) and conformal mapping, which have previously been used to derive analytic solutions for SCLC density (SCLCD) for nonplanar one-dimensional geometries, to obtain mathematical relationships for any multi-dimensional macroscopic diode with finite cathode and anode. We first derive a universal mathematical relationship between space-charge limited potential and vacuum potential for any diode and apply this technique to determine SCLCD for an eccentric spherical diode. We …

Attenuation Of Several Common Building Materials: Millimeter-Wave Frequency Bands 28, 73, And 91 Ghz, Mahfuza Khatun, Changyu Guo, Hani Mehrpouyan

Electrical and Computer Engineering Faculty Publications and Presentations

Future cellular systems will make use of millimeter-wave (mm-wave) frequency bands. Many users in these bands are located indoors, i.e., inside buildings, homes, and offices. The typical building material attenuations in these high-frequency ranges are of interest for link budget calculations. In this article, we report on a collaborative measurement campaign to find the attenuation of several typical building materials in three potential mm-wave bands (28, 73, and 91 GHz). Using directional antennas, we took multiple measurements at multiple locations using narrow-band and wideband signals and averaged out residual small-scale fading effects. The materials include clear glass, drywall (plasterboard), plywood, …

Dual Multivector Model Predictive Control For The Power Converters Of A Floating Owc Wec, Marcos Blanco, Dionisio Ramirez, Mohammad Ebrahim Zarei, Mahima Gupta

Electrical and Computer Engineering Faculty Publications and Presentations

Oscillating Water Column (OWC) is one of the most well-known wave energy converter (WEC). Typically, OWCs are installed in rocky shores or in custom-built breakwaters. However, since the wave profile is more favorable in an open sea, it can also be installed in a point absorber in order to increase the energy extraction.

This paper presents the development of a new dual Multivector Model Predictive Control (MMPC) for the power converters of a floating OWC WEC. The fast dynamic response featured by the proposed MMPC has proven to be very suitable to deal with the highly variable torque and velocity …

Effectiveness Assessment Of The Search-Based Statistical Structural Testing, Yang Shi, Xiaoyu Song, Marek A. Perkowski, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

Search-based statistical structural testing (SBSST) is a promising technique that uses automated search to construct input distributions for statistical structural testing. It has been proved that a simple search algorithm, for example, the hill-climber is able to optimize an input distribution. However, due to the noisy fitness estimation of the minimum triggering probability among all cover elements (Tri-Low-Bound), the existing approach does not show a satisfactory efficiency. Constructing input distributions to satisfy the Tri-Low-Bound criterion requires an extensive computation time. Tri-Low-Bound is considered a strong criterion, and it is demonstrated to sustain a high fault-detecting ability. This article tries to …

Novel Quantum Algorithms To Minimize Switching Functions Based On Graph Partitions, Peng Gao, Marek A. Perkowski, Yiwei Li, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

After Google reported its realization of quantum supremacy, Solving the classical problems with quantum computing is becoming a valuable research topic. Switching function minimization is an important problem in Electronic Design Automation (EDA) and logic synthesis, most of the solutions are based on heuristic algorithms with a classical computer, it is a good practice to solve this problem with a quantum processer. In this paper, we introduce a new hybrid classic quantum algorithm using Grover’s algorithm and symmetric functions to minimize small Disjoint Sum of Product (DSOP) and Sum of Product (SOP) for Boolean switching functions. Our method is based …

An Adjustable Stiffness Torsional Magnetic Spring With A Linear Stroke Length, Dawei Che, Jonathan Z. Bird, Alex Hagmüller, Md Emrad Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents the analysis, mechanical design, and proof-of-principle experimental testing of a new type of adjustable stiffness torsional magnetic spring for an ocean generator application. Unlike prior published designs the rotary magnetic spring is shown to have a highly linear adjustable stroke length. The presented torsional spring is experimentally shown to be able to create a ± 45° angular stroke range with a peak torque of ± 39.1 N·m. The stiffness is adjusted by using a stepper motor to axially adjust the axial magnet offset. The stepper motor contains a brake so that power is not expended when maintaining …

Fourth-Order Nonlinear Distortion To The Power Spectrum Of Rf Amplifiers, Xianzhen Yang, Shiyu Li, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

Even-order intermodulation distortions are often considered easy to filter in narrowband radio frequency (RF) wireless systems because they are usually located far away from the desired passband and adjacent bands. However, even-order intermodulation distortions have recently attracted more interest with the increasing popularity of wideband RF appli- cations. The authors’ previous work was devoted to establishing the power spectrum model of second-order intermodulation distortion. Motivated by the latest efforts on RF power amplifier linearization with second-order and fourth-order intermodulation, our focus now is to establish a power spectrum model of fourth-order intermodulation distortion which can be used to discuss the …

Deep Learning Approach For Screening Autism Spectrum Disorder In Children With Facial Images And Analysis Of Ethnoracial Factors In Model Development And Application, Angelina Lu, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Autism spectrum disorder (ASD) is a developmental disability that can cause significant social, communication, and behavioral challenges. Early intervention for children with ASD can help to improve their intellectual ability and reduces autistic symptoms. Multiple clinical researches have suggested that facial phenotypic differences exist between ASD children and typically developing (TD) children. In this research, we propose a practical ASD screening solution using facial images through applying VGG16 transfer learning-based deep learning to a unique ASD dataset of clinically diagnosed children that we collected. Our model produced a 95% classification accuracy and 0.95 F1-score. The only other reported study using …

Proximal Policy Optimization For Radiation Source Search, Philippe Erol Proctor, Christof Teuscher, Adam A. Hecht, Marek Osiński

Electrical and Computer Engineering Faculty Publications and Presentations

Rapid search and localization for nuclear sources can be an important aspect in preventing human harm from illicit material in dirty bombs or from contamination. In the case of a single mobile radiation detector, there are numerous challenges to overcome such as weak source intensity, multiple sources, background radiation, and the presence of obstructions, i.e., a non-convex environment. In this work, we investigate the sequential decision making capability of deep reinforcement learning in the nuclear source search context. A novel neural network architecture (RAD-A2C) based on the advantage actor critic (A2C) framework and a particle filter gated recurrent unit for …

Head-Wave Correlations In Layered Seabed: Theory And Modeling, Jie Li, Martin Siderius, Peter Gerstoft, Jun Fan, Lanfranco Muzi

Electrical and Computer Engineering Faculty Publications and Presentations

This paper derives travel times and arrival angles of head-wave correlations from ocean ambient noise in shallow water over a layered seabed. The upcoming and surface reflected head-wave noise signal received at two receivers from the same interface are correlated, and their travel time differences give the travel times of the head-wave correlations. The arrival angle of head-wave correlations from an interface depends on sound speeds in the layers above and just below. The predictions of head-wave correlations from a seabed with two layers and the corresponding inversion results are verified with simulations.

A 3d Crossbar Architecture For Both Pipeline And Parallel Computations, John M. Acken, Muayad J. Aljafar

Electrical and Computer Engineering Faculty Publications and Presentations

A 3D architecture made up of a CMOS layer combined with a 3D stack of bipolar memristor crossbar arrays provides an innovative approach to hardware support for utilizing the strength of CMOS combined with the strength of memristors. Memristors have been evaluated for implementing a broad spectrum of applications such as memory, computations, hardware-based security primitives, cryptography, etc., and numerous studies have shown that memristors are desirable candidates for such applications. This paper proposes a novel 3D memristive crossbar architecture (i.e., a stack of memristive crossbar arrays built on top of CMOS substrate) with a specific focus on the way …