Engineering Commons^™

Fiber-Optic Temperature And Flow Sensory System And Methods, Ming Han, Guigen Liu, Weilin Hou, Qiwen Shen

Department of Electrical and Computer Engineering: Faculty Publications

A fiber optic sensor, a process for utilizing a fiber optic sensor, and a process for fabricating a fiber optic sensor are described, where a double-side-polished silicon pillar is attacked to an optical fiber tip and forms, a Fabry-Perot cavity. In an implementation, a fiber optic sensor in accordance with an examplary embodiment includes an optical fiber configured to be coupled to a light source and a spectrometer; and a single silicon layer or multiple silicon layers disposed on an end face of the optical fiber, where each of the silicon layer(s) defines a Fabry-Perot interferometer, and where the sensor …

Generating Energy Data For Machine Learning With Recurrent Generative Adversarial Networks, Mohammad Navid Fekri, Ananda M. Ghosh, Katarina Grolinger

Electrical and Computer Engineering Publications

The smart grid employs computing and communication technologies to embed intelligence into the power grid and, consequently, make the grid more efficient. Machine learning (ML) has been applied for tasks that are important for smart grid operation including energy consumption and generation forecasting, anomaly detection, and state estimation. These ML solutions commonly require sufficient historical data; however, this data is often not readily available because of reasons such as data collection costs and concerns regarding security and privacy. This paper introduces a recurrent generative adversarial network (R-GAN) for generating realistic energy consumption data by learning from real data. Generativea adversarial …

Review—Machine Learning Techniques In Wireless Sensor Network Based Precision Agriculture, Yemeserach Mekonnen, Srikanth Namuduri, Lamar Burton, Arif I. Sarwat, Shekhar Bhansali

Electrical and Computer Engineering Faculty Publications

The use of sensors and the Internet of Things (IoT) is key to moving the world's agriculture to a more productive and sustainable path. Recent advancements in IoT, Wireless Sensor Networks (WSN), and Information and Communication Technology (ICT) have the potential to address some of the environmental, economic, and technical challenges as well as opportunities in this sector. As the number of interconnected devices continues to grow, this generates more big data with multiple modalities and spatial and temporal variations. Intelligent processing and analysis of this big data are necessary to developing a higher level of knowledge base and insights …

Localized Dielectric Loss Heating In Dielectrophoresis Devices, Tae Joon Kwak, Imtiaz Hossen, Rashid Bashir, Woo-Jin Chang, Chung-Hoon Lee

Electrical and Computer Engineering Faculty Research and Publications

Temperature increases during dielectrophoresis (DEP) can affect the response of biological entities, and ignoring the effect can result in misleading analysis. The heating mechanism of a DEP device is typically considered to be the result of Joule heating and is overlooked without an appropriate analysis. Our experiment and analysis indicate that the heating mechanism is due to the dielectric loss (Debye relaxation). A temperature increase between interdigitated electrodes (IDEs) has been measured with an integrated micro temperature sensor between IDEs to be as high as 70 °C at 1.5 MHz with a 30 V_pp applied voltage to our ultra-low …

An Enhanced Two-Stage Grid-Connected Linear Parameter Varying Photovoltaic System Model For Frequency Support Strategy Evaluation, Colin Levis, Cathal O' Loughlin, Terence O' Donnell, Martin Hill

Dept. of Electrical & Electronic Engineering Publications

Securing a future sustainable decarbonised economy involves moving towards a system with rising penetration levels of distributed photovoltaics (PVs) within the low voltage distribution network (LVDN). This power system evolution is displacing conventional generators and has resulted in a decline in inertia that is essential for frequency stability. Emerging network codes require PV generators to maintain a scheduled curtailed active power (CAP) reserve for under-frequency contingencies. In this paper, the development, verification and application of an enhanced, two-stage grid-connected, state-space, linear parameter varying (LPV) PV system model is presented. The LPV model provides accurate and efficient modelling for PV systems …

Founding The Domain Of Ai Forensics, Ibrahim Baggili, Vahid Behzadan

Electrical & Computer Engineering and Computer Science Faculty Publications

With the widespread integration of AI in everyday and critical technologies, it seems inevitable to witness increasing instances of failure in AI systems. In such cases, there arises a need for technical investigations that produce legally acceptable and scientifically indisputable findings and conclusions on the causes of such failures. Inspired by the domain of cyber forensics, this paper introduces the need for the establishment of AI Forensics as a new discipline under AI safety. Furthermore, we propose a taxonomy of the subfields under this discipline, and present a discussion on the foundational challenges that lay ahead of this new research …

A Wideband, Circularly Polarized, Directive Antenna With A Circular Reflector, Tyler J. Mcpherson, Zabed Iqbal, Sungkyun Lim

Department of Electrical & Computer Engineering Faculty Research & Publications

A two-element, patch antenna with a single feed is presented to achieve wideband, circular polarization, and uni-directional radiation. The driven element of the antenna has a rotated, corner-truncated radiating patch to achieve circularly polarized radiation with an offset microstrip feedline in the front side. The back side of the driven element comprises a wide hexagonal slot, eight meander tips, and a parasitic patch in the center. A circular reflector is added behind the driven element to increase realized gain toward the front side direction of the driven element. A prototype of the antenna is fabricated for validation. In both simulation …

Introducing Phonetic Information To Speaker Embedding For Speaker Verification, Yi Liu, Liang He, Michael T. Johnson

Electrical and Computer Engineering Faculty Publications

Phonetic information is one of the most essential components of a speech signal, playing an important role for many speech processing tasks. However, it is difficult to integrate phonetic information into speaker verification systems since it occurs primarily at the frame level while speaker characteristics typically reside at the segment level. In deep neural network-based speaker verification, existing methods only apply phonetic information to the frame-wise trained speaker embeddings. To improve this weakness, this paper proposes phonetic adaptation and hybrid multi-task learning and further combines these into c-vector and simplified c-vector architectures. Experiments on National Institute of Standards and Technology …

College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Optimal Allocation Of Energy Storage And Wind Generation In Power Distribution Systems, Carlos Mendoza

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

The advent of energy storage technologies applications for the electric power system gives new tools for planners to cope with the operation challenges that come from the integration of renewable generation in medium voltage networks. This work proposes and implements an optimization model for Battery Energy Storage System (BESS) and distributed generation allocation in radial distribution networks. The formulation aims to assist distribution system operators in the task of making decisions on energy storage investment, BESSs' operation, and distributed generation penetration's level to minimize electricity costs. The BESSs are required to participate in energy arbitrage and voltage control. In addition, …

Amodal Instance Segmentation And Multi-Object Tracking With Deep Pixel Embedding, Yanfeng Liu

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

This thesis extends upon the representational output of semantic instance segmentation by explicitly including both visible and occluded parts. A fully convolutional network is trained to produce consistent pixel-level embedding across two layers such that, when clustered, the results convey the full spatial extent and depth ordering of each instance. Results demonstrate that the network can accurately estimate complete masks in the presence of occlusion and outperform leading top-down bounding-box approaches.

The model is further extended to produce consistent pixel-level embeddings across two consecutive image frames from a video to simultaneously perform amodal instance segmentation and multi-object tracking. No post-processing …

Aluminum/Carbon Composites Materials Fabricated By The Powder Metallurgy Process, Amélie Veillère, Hiroki Kurita, Akira Kawasaki, Yongfeng Lu, Jean-Marc Heintz, Jean-François Silvain

Department of Electrical and Computer Engineering: Faculty Publications

Aluminum matrix composites reinforced with carbon fibers or diamond particles have been fabricated by a powder metallurgy process and characterized for thermal management applications. Al/C composite is a nonreactive system (absence of chemical reaction between the metallic matrix and the ceramic reinforcement) due to the presence of an alumina layer on the surface of the aluminum powder particles. In order to achieve fully dense materials and to enhance the thermo-mechanical properties of the Al/C composite materials, a semi-liquid method has been carried out with the addition of a small amount of Al-Si alloys in the Al matrix. Thermal conductivity and …

Sensor Emulation With Physiolocal Data In Immersive Virtual Reality Driving Simulator, Jungsu Pak, Oliver Mathias, Ariane Guirguis, Uri Maoz

Student Scholar Symposium Abstracts and Posters

Can we enhance the safety and comfort of AVs by training AVs with physiological data of human drivers? We will train and compare AV algorithm with/without physiological data.

The Trolley Problem In Virtual Reality, Jungsu Pak, Ariane Guirguis, Nicholas Mirchandani, Scott Cummings, Uri Maoz

Student Scholar Symposium Abstracts and Posters

Would people react to the Trolley problem differently based on the medium? Immersive Virtual Reality Driving Simulator was used to examine participants respond to the trolley problem in a realistic and controlled simulated environment.

The Challenges Facing Autonomous Vehicles And The Progress In Addressing Them, Garrett Johnson

Senior Honors Theses

Autonomous vehicles are an emerging technology that faces challenges, both technical and socioeconomic. This paper first addresses specific technical challenges, such as parsing visual data, communicating with other entities, and making decisions based on environmental knowledge. The technical challenges are to be addressed by the fields of image processing, Vehicle to Everything Communication (V2X), and decision-making systems. Non-technical challenges such as ethical decision making, social acceptance, and economic pushback are also discussed. Ethical decision making is discussed in the framework of deontology vs utilitarianism, while social acceptance of utilitarian autonomous vehicles is also investigated. Last, the likely economic impact is …

Second-Order Fault Tolerant Extended Kalman Filter For Discrete Time Nonlinear Systems, Xin Wang, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

As missing sensor data may severely degrade the overall system performance and stability, reliable state estimation is of great importance in modern data-intensive control, computing, and power systems applications. Aiming at providing a more robust and resilient state estimation technique, this paper presents a novel second-order fault-tolerant extended Kalman filter estimation framework for discrete-time stochastic nonlinear systems under sensor failures, bounded observer-gain perturbation, extraneous noise, and external disturbances condition. The failure mechanism of multiple sensors is assumed to be independent of each other with various malfunction rates. The proposed approach is a locally unbiased, minimum estimation error covariance based nonlinear …

Comparative Study Of Winding Configurations Of A Five-Phase Flux-Switching Pm Machine, Hao Chen, Xiangdong Liu, Ayman M. El-Refaie, Jing Zhao, Nabeel Demerdash, Jiangbiao He

Electrical and Computer Engineering Faculty Research and Publications

This paper introduces a general method for determination of the most suitable winding configurations for five-phase flux-switching permanent magnet (FSPM) machines, associated with feasible stator/rotor-pole combinations. Consequently, the effect of winding configurations on the performance of a five-phase outer-rotor FSPM machine is thoroughly investigated, including non-overlapping concentrated windings (single-layer, double-layer, and multi-layer) as well as distributed winding. The electromagnetic characteristics in the low-speed region, the flux-weakening capability in the high-speed region, and the fault-tolerant capability under faulty situations are evaluated and compared in detail. This work shows that compared with the conventional single-layer or double-layer concentrated windings, the FSPM machine …

Normalization Of Unconstrained Handwritten Words In Terms Of Slope And Slant Correction, Suman Kumar Bera, Akash Chakrabarti, Sagnik Lahiri, Elisa H. Barney Smith, Ram Sarkar

Electrical and Computer Engineering Faculty Publications and Presentations

In offline handwritten text slope (or skew) and slant are inevitably introduced, but to varying degrees depending on several factors, such as the writing style, speed and mood of the writers. Therefore slope and slant detection in offline handwritten text and their subsequent correction have become the critical preprocessing steps for document analysis and retrieval systems to neutralize the variability of writing styles and to improve the performance of word and character recognition systems. In this paper, we present new methods that use two novel core-region detection techniques to estimate both the slope and slant angles of offline handwritten word …

Energy-Performance Scalability Analysis Of A Novel Quasi-Stochastic Computing Approach, Prashanthi Metku, Ramu Seva, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

Stochastic computing (SC) is an emerging low-cost computation paradigm for efficient approximation. It processes data in forms of probabilities and offers excellent progressive accuracy. Since SC's accuracy heavily depends on the stochastic bitstream length, generating acceptable approximate results while minimizing the bitstream length is one of the major challenges in SC, as energy consumption tends to linearly increase with bitstream length. To address this issue, a novel energy-performance scalable approach based on quasi-stochastic number generators is proposed and validated in this work. Compared to conventional approaches, the proposed methodology utilizes a novel algorithm to estimate the computation time based on …

Structured Iterative Hard Thresholding For Categorical And Mixed Data Types, Thy Nguyen, Tayo Obafemi-Ajayi

Electrical and Computer Engineering Faculty Research & Creative Works

In many applications, data exists in a mixed data type format, i.e. a combination of nominal (categorical) and numerical features. A common practice for working with categorical features is to use an encoding method to transform the discrete values into numeric representation. However, numeric representation often neglects the innate structures in categorical features, potentially degrading the performance of learning algorithms. Utilizing the numeric representation could also limit interpretation of the learned model, such as finding the most discriminative categorical features or filtering irrelevant attributes. In this work, we extend the iterative hard thresholding (IHT) algorithm to quantify the structure of …

Comparison And Design Optimization Of A Five-Phase Flux-Switching Pm Machine For In-Wheel Traction Applications, Hao Chen, Xiangdong Liu, Nabeel Demerdash, Ayman M. El-Refaie, Jing Zhao, Jiangbiao He

Electrical and Computer Engineering Faculty Research and Publications

A comparative study of five-phase outer-rotor flux-switching permanent magnet (FSPM) machines with different topologies for in-wheel traction applications is presented in this paper. Those topologies include double-layer winding, single-layer winding, C-core, and E-core configurations. The electromagnetic performance in the low-speed region, the flux-weakening capability in the high-speed region, and the fault-tolerance capability are all investigated in detail. The results indicate that the E-core FSPM machine has performance advantages. Furthermore, two kinds of E-core FSPM machines with different stator and rotor pole combinations are optimized, respectively. In order to reduce the computational burden during the large-scale optimization process, a mathematical technique …

Iomt Malware Detection Approaches: Analysis And Research Challenges, Mohammad Wazid, Ashok Kumar Das, Joel J.P.C. Rodrigues, Sachin Shetty, Youngho Park

VMASC Publications

The advancement in Information and Communications Technology (ICT) has changed the entire paradigm of computing. Because of such advancement, we have new types of computing and communication environments, for example, Internet of Things (IoT) that is a collection of smart IoT devices. The Internet of Medical Things (IoMT) is a specific type of IoT communication environment which deals with communication through the smart healthcare (medical) devices. Though IoT communication environment facilitates and supports our day-to-day activities, but at the same time it has also certain drawbacks as it suffers from several security and privacy issues, such as replay, man-in-the-middle, impersonation, …

Pixel-Level Deep Multi-Dimensional Embeddings For Homogeneous Multiple Object Tracking, Mateusz Mittek

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

The goal of Multiple Object Tracking (MOT) is to locate multiple objects and keep track of their individual identities and trajectories given a sequence of (video) frames. A popular approach to MOT is tracking by detection consisting of two processing components: detection (identification of objects of interest in individual frames) and data association (connecting data from multiple frames). This work addresses the detection component by introducing a method based on semantic instance segmentation, i.e., assigning labels to all visible pixels such that they are unique among different instances. Modern tracking methods often built around Convolutional Neural Networks (CNNs) and additional, …

A Review Of Integrated Propulsion, Suspension And Guidance Passive Guideway Maglev Technologies, Jonathan Bird

Electrical and Computer Engineering Faculty Publications and Presentations

This paper provides a review of integrated propulsion, suspension and guidance maglev technology that use fully passive guideway structures.

Ldakm-Eiot: Lightweight Device Authentication And Key Management Mechanism For Edge-Based Iot Deployment, Mohammad Wazid, Ashok Kumar Das, Sachin Shetty, Joel J. P. C. Rodrigues, Youngho Park

VMASC Publications

In recent years, edge computing has emerged as a new concept in the computing paradigm that empowers several future technologies, such as 5G, vehicle-to-vehicle communications, and the Internet of Things (IoT), by providing cloud computing facilities, as well as services to the end users. However, open communication among the entities in an edge based IoT environment makes it vulnerable to various potential attacks that are executed by an adversary. Device authentication is one of the prominent techniques in security that permits an IoT device to authenticate mutually with a cloud server with the help of an edge node. If authentication …

Nonlinear Loss Model In Absorptive-Type Ferrite Frequency-Selective Limiters, Anatoliy O. Boryssenko, Scott M. Gillette, Marina Y. Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

Absorptive-type ferrite-based frequency-selective limiters (FSLs) utilize nonlinear (NL) phenomena in magnetized ferrites to provide real-time analog signal processing of RF/microwave electromagnetic (EM) signals. There are no commercially available modeling tools that simulate these interactions, and the development and optimization of FSLs are largely done experimentally. FSL modeling and design is complicated by NL, multiscale, and Multiphysics nature of operation. In this article, an NL loss model in a ferrite is proposed and implemented in an efficient numerical algorithm. The equivalent linear magnetic loss tangent is represented in a closed form. A full-wave numerical EM model with high-fidelity meshing is set …

Design And Sensitivity Analysis Of Ebg Stripline Common-Mode Filters, Marina Y. Koledintseva, Sergiu Radu, Joseph Nuebel

Electrical and Computer Engineering Faculty Research & Creative Works

Workflow of electromagnetic bandgap (EBG) common-mode (CM) filter design of edge-coupled differential pairs on a printed circuit board (PCB) and sensitivity of its characteristics to variations of geometrical and material parameters are discussed. A number of simple 20-GHz EBG CM notch filters for differential strip line pairs are designed using full-wave numerical electromagnetic modeling, fabricating, and testing. The cases of one and two strip line differential pairs crossing the EBG patches are considered. The modeled and measured mixed-mode S-parameters are analyzed as functions of geometrical parameters, including size and number of EBG patches, gaps between them, geometry and position of …

Analysis And Introduction Of Effective Permeability With Additional Air-Gaps On Wireless Power Transfer Coils For Electric Vehicle Based On Sae J2954 Recommended Practice, Dongwook Kim, Hongseok Kim, Anfeng Huang, Qiusen He, Hanyu Zhang, Seungyoung Ahn, Yuyu Zhu, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

The wireless power transfer (WPT) method for electric vehicles (EVs) is becoming more popular, and to ensure the interoperability of WPT systems, the Society of Automotive Engineers (SAE) established the J2954 recommended practice (RP). It includes powering frequency, electrical parameters, specifications, testing procedures, and other contents for EV WPT. Specifically, it describes the ranges of self-inductances of the transmitting coil, the receiving coil, and coupling coefficient (k), as well as the impedance matching values of the WPT system. Following the electrical parameters listed in SAE J2954 RP is crucial to ensure the EV wireless charging system is interoperable. This paper …

Transmission-Scale Battery Energy Storage Systems: A Systematic Literature Review, Kevin Marnell, Manasseh Obi, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

When the transmission capacity of an electrical system is insufficient to adequately serve customer demand, the transmission system is said to be experiencing congestion. More transmission lines can be built to increase capacity. However, transmission congestion typically only occurs during periods of peak demand, which occur just a few times per year; capitol-intensive investments in new transmission capacity address problems that occur infrequently. Alternative solutions to alleviated transmission congestion have been devised, including generation curtailment, demand response programs, and various remedial action schema. Though not currently a common solution, battery energy storage systems can also provide transmission congestion relief. Technological …

E700xd Portable Doppler Radar Energy Systems Analysis, Brandon M. Bailey [*], Torrey J. Wagner, Jada Williams

Faculty Publications

Occurring in industrialized nations, inexpensive and abundantly available power is routinely taken for granted. However, energy resilience and to a lesser extent price are key concerns when considering potential solutions for disaster response, disaster relief, or military operations. The Department of Defense (DoD) currently uses a 5 kW generator to power the E700XD portable Doppler radar system when grid power is unavailable [1]. While the radar has an approximate power consumption of 2.5 kW, there is a potential for higher demand due to weather conditions [2]. This paper examines the cost of operating a currently installed generator, compared to the …