Electrical and Computer Engineering Commons^™

Architecture Design And Optimization Of Edge-Enabled Smart Grids, Adetola B. Adeniran

USF Tampa Graduate Theses and Dissertations

The emergence of modern monitoring, communication, computation, and controlequipment into power systems has made them evolve into smart grids that can be thought of as the electric grid of things. This evolution has enhanced the efficiency of the power systems through the availability of a large volume of system data that can help with system functions, nevertheless, it has intensified the communication and computation burden on these systems. While many of such computations were traditionally deployed in central servers, new technologies such as edge computing can provide unique opportunities to address some of the computational challenges and improve the responsiveness …

The Role Of Network Components In Improving The Reliability And Survivability Of Mobile Communication Networks, Dilmurod Davronbekov, Utkir Karimovich Matyokubov

Acta of Turin Polytechnic University in Tashkent

This article compares the different architectures of mobile communication networks (MCN) and examines the survivability of the network. Typical survival strategies for improving MCN survivability, failure mitigation strategies for network elements, wireless network survival rates, failure scenarios at MCN levels, and survival indicators are presented. The importance of fiber-optic communication in the construction of communication lines between MCN components has been studied. The issue of designing MCNs in a cost-effective and highly viable way is considered, and the necessary expressions of the design process are given.

Static Characteristics Of Thermal Humidity Converters Of Liquid Materials In Continuous Flow, N.I. Avezova, P.R. Ismatullaev, Paraxat Matyakubova

Chemical Technology, Control and Management

Thermal systems with distributed heat sources based on a pipeline segment with radial holes are proposed for the development of designs of thermal humidity converters for liquid materials. Across the liquid flow there are tubular arguments with cylindrical heat-sensitive elements, on the surface of which the heating element winding was wound, which significantly increased their sensitivity, speed, reliability and allowed the use of standard semiconductor heat-sensitive elements.

Controlling And Forecasting The Reliability Of Integrated Circuits Of Radio Systems Transmitting Information, Abdulaziz M. Nazarov Prof, Dilmurod A. Davronbekov Prof.

Chemical Technology, Control and Management

The issues of forecasting the reliability of integrated circuits, which are the main element base of modern radio engineering information transmission systems, are considered. Methods of parametric and functional control are described to determine the correspondence of the static and dynamic parameters of microcircuits to the required values. A combined method for determining the operating parameters of microcircuits is also described. The advantage of this method in addition to the two above methods is indicated that it combines the function of controlling the operation of the entire control system. Two approaches for predicting reliability are given, as well as mathematical …

Optimal Sizing Of Energy Storage With Embedded Wind Power Generation, Nicholas Roche, Jane Courtney

Articles

Energy storage technologies are key to increased penetration of renewable energies on the distribution system. Not only do they increase availability of energy, but they contribute to the overall reliability of the system. However, the cost of large-scale storage systems can often be prohibitive, and storage needs to be sized appropriately, both to fill the energy gaps inevitable in renewable energies such as wind and to minimize costs. In this work, a Monte Carlo Simulation is performed to optimally size an energy storage system while minimizing overall system cost. 30 years of historical wind speed data are used to model …

Reliability Comparisons Of Mobile Network Operators: An Experimental Case Study From A Crowdsourced Dataset, Engi̇n Zeydan, Ahmet Yildirim

Turkish Journal of Electrical Engineering and Computer Sciences

It is of great interest for Mobile Network Operators (MNOs) to know how well their network infrastructure performance behaves in different geographical regions of their operating country compared to their horizontal competitors. However, traditional network monitoring and measurement methods of network infrastructure use limited numbers of measurement points that are insufficient for detailed analysis and expensive to scale using an internal workforce. On the other hand, the abundance of crowdsourced content can engender various unforeseen opportunities for MNOs to cope with this scaling problem. This paper investigates end-to-end reliability and packet loss (PL) performance comparisons of MNOs using a previously …

An Efficient Reliability Simulation Tool For Lifetime-Aware Analog Circuit Synthesis, Engi̇n Afacan

Turkish Journal of Electrical Engineering and Computer Sciences

Time-dependent degradation (aging) has become more severe in modern CMOS technologies. Therefore, it is highly critical to capture the variation effects and design reliable circuits against aging. Simulation of time-dependent variations is quite complicated since the degradation is a function of time, where the step count of simulation directly affects the accuracy and the efficiency of the analysis. Commercial simulator tools use a constant step count during reliability simulations, in which choosing a large step count degrades the efficiency whereas keeping it small may result in accuracy problems. To overcome this bottleneck, a couple of different approaches have been proposed …

Superconducting Radio-Frequency Cavity Fault Classification Using Machine Learning At Jefferson Laboratory, Chris Tennant, Adam Carpenter, Tom Powers, Anna Shabalina Solopova, Lasitha Vidyaratne, Khan Iftekharuddin

Electrical & Computer Engineering Faculty Publications

We report on the development of machine learning models for classifying C100 superconducting radio-frequency (SRF) cavity faults in the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. CEBAF is a continuous-wave recirculating linac utilizing 418 SRF cavities to accelerate electrons up to 12 GeV through five passes. Of these, 96 cavities (12 cryomodules) are designed with a digital low-level rf system configured such that a cavity fault triggers waveform recordings of 17 rf signals for each of the eight cavities in the cryomodule. Subject matter experts are able to analyze the collected time-series data and identify which of the …

Sub-Synchronous Resonance Analysis And Detection, Igor Brandao Machado Matsuo

Electrical Engineering Dissertations - Archive

With the increasing penetration of renewable generation resources, power grids have become more susceptible to sub-synchronous resonance phenomena, especially to sub-synchronous control interaction, which produces fast-growing oscillations. The power system operation requirements for a reliable, fast and accurate detection and monitoring system for protection and mitigation purposes are increasing. Besides, risk assessment analysis during grid planning and update studies can be extremely time-consuming due to a large number of possible grid configurations and small time-steps required for the simulation of detailed electromagnetic transient (EMT) models. The first part of this dissertation aims to provide an optimized tool for SSR risk …

Targeted Germanium Ion Irradiation Of Aluminum Gallium Nitride/Gallium Nitride High Electron Mobility Transistors, Melanie E. Mace

Theses and Dissertations

Microscale beams of germanium ions were used to target different locations of aluminum galliumnitride/gallium nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) to determine location dependent radiation effects. 1.7 MeV Ge ions were targeted at the gap between the gate and the drain to observe displacement damage effects while 47 MeV Ge ions were targeted at the gate to observe ionization damage effects. Electrical data was taken pre, during, and post irradiation. To separate transient from permanent degradation, the devices were characterized after a room temperature anneal for at least 30 days. Optical images were also analyzed pre and post irradiation. …

Improving The Single Event Effect Response Of Triple Modular Redundancy On Sram Fpgas Through Placement And Routing, Matthew Joel Cannon

Theses and Dissertations

Triple modular redundancy (TMR) with repair is commonly used to improve the reliability of systems. TMR is often employed for circuits implemented on field programmable gate arrays (FPGAs) to mitigate the radiation effects of single event upsets (SEUs). This has proven to be an effective technique by improving a circuit's sensitive cross-section by up to 100x. However, testing has shown that the improvement offered by TMR is limited by upsets in single configuration bits that cause TMR to fail.This work proposes a variety of mitigation techniques that improve the effectiveness of TMR on FPGAs. These mitigation techniques can alter the …

Improving Power Network Resilience Against Threats, Hamzeh Davarikia

LSU Doctoral Dissertations

The work reported in this dissertation aims at developing a practical tool for utility transmission planners to improve the power network resilience against high-impact, low-frequency events (HILF). Such events rarely happen, but when occurred are catastrophic. In this dissertation, we studied the impact of HILF from the static and dynamic point of view and proposed the planning strategy to lower the devastating effect of the HILF.

In the static analysis, we consider the steady-state situation of the power grids and plan to protect the grid’s components, i.e., generators, buses, and transmission lines, to maximize preserving demand in a disastrous situation. …

H2 Control For Improved Stability Of Multi-Area Electric Power System With High Levels Of Inverter-Based Generation, Muthanna Abdulkareem Al-Sarray

Graduate Theses and Dissertations

Increased generation capacity from non-dispatchable energy resources such as wind and solar has created challenges to ensuring the reliable delivery of electric power. This research develops a systematic three-step method of assessing the reliability of electric power systems under a variety of different possible fault conditions to ensure that overall system stability is preserved in a manner the meets regulatory requirements. The first step is a risk-based reliability method (RBRM) that accounts for the probability of a line outage versus the severity of impact. This allows system planners to judiciously allocate expenses for reliability improvements based on the greatest economic …

Revamping Timing Error Resilience To Tackle Choke Points At Ntc, Aatreyi Bal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The growing market of portable devices and smart wearables has contributed to innovation and development of systems with longer battery-life. While Near Threshold Computing (NTC) systems address the need for longer battery-life, they have certain limitations. NTC systems are prone to be significantly affected by variations in the fabrication process, commonly called process variation (PV). This dissertation explores an intriguing effect of PV, called choke points. Choke points are especially important due to their multifarious influence on the functional correctness of an NTC system. This work shows why novel research is required in this direction and proposes two techniques to …

Novel Test Fixture For Characterizing Mems Switch Microcontact Reliability And Performance, Protap Mahanta, Farhana Anwar, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

In microelectromechanical systems (MEMS) switches, the microcontact is crucial in determining reliability and performance. In the past, actual MEMS devices and atomic force microscopes (AFM)/scanning probe microscopes (SPM)/nanoindentation-based test fixtures have been used to collect relevant microcontact data. In this work, we designed a unique microcontact support structure for improved post-mortem analysis. The effects of contact closure timing on various switching conditions (e.g., cold-switching and hot-switching) was investigated with respect to the test signal. Mechanical contact closing time was found to be approximately 1 us for the contact force ranging from 10–900 μN. On the other hand, for the 1 …

Tapu: Test And Pick Up-Based $K$-Connectivity Restoration Algorithm For Wireless Sensor Networks, Vahi̇d Khali̇lpour Akram, Orhan Dağdevi̇ren

Turkish Journal of Electrical Engineering and Computer Sciences

A $k$-connected wireless sensor network remains connected if any $k$-1 arbitrary nodes stop working. The aim of movement-assisted $k$-connectivity restoration is to preserve the $k$-connectivity of a network by moving the nodes to the necessary positions after possible failures in nodes. This paper proposes an algorithm named TAPU for $k$-connectivity restoration that guarantees the optimal movement cost. Our algorithm improves the time and space complexities of the previous approach (MCCR) in both best and worst cases. In the proposed algorithm, the nodes are classified into safe and unsafe groups. Failures of safe nodes do not change the $k$ value of …

Novel Node Deployment Scheme And Reliability Quantitative Analysis For An Iot-Based Monitoring System, Yinghua Tong, Liqin Tian, Jing Li

Turkish Journal of Electrical Engineering and Computer Sciences

The Internet of things (IoT) is highly suitable for military, environmental, agricultural, and other remote real-time monitoring applications. A reliable topology ensures a stable and dependable monitoring system. Considering the research of an IoT-based air pollution monitoring system for industrial emissions as background, this study proposes a novel dual redundant node deployment scheme. Specifically, hexagonal clustering is proposed for the internal regions. In addition, relationship and quantification formulas for a monitoring area are presented, and the communication range, total number of layers of the topology, and number of cluster headers are determined. Interruptions in a monitoring system may reduce the …

Reliability Issues Caused By The Retirement Of Large Thermal Generation Facilities: An Irish Case Study, Kyle Lawson, Jane Courtney

Conference papers

Like all developed countries Ireland faces increasing pressure to reduce their carbon footprint. Part of the governments plans include the scaling back of fossil fuel generation facilities and increasing renewable resources. Moneypoint is Irelands only coal fired generation station. In 2025 Moneypoint is due to reach the end of its life cycle. At this point the Irish government will have to make a decission on the future of the generation facility. Currently Moneypoint is responsible for the generation of approximately 10 % of Irelands energy needs. In this paper, the removal of Moneypoint from the Irish generation portfolio will be …

Characterization Of Self-Heating Effects And Assessment Of Its Impact On Reliability In Finfet Technology, Peter Christopher Paliwoda

Dissertations

The systematically growing power (heat) dissipation in CMOS transistors with each successive technology node is reaching levels which could impact its reliable operation. The emergence of technologies such as bulk/SOI FinFETs has dramatically confined the heat in the device channel due to its vertical geometry and it is expected to further exacerbate with gate-all-around transistors.

This work studies heat generation in the channel of semiconductor devices and measures its dissipation by means of wafer level characterization and predictive thermal simulation. The experimental work is based on several existing device thermometry techniques to which additional layout improvements are made in state …

Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut

Graduate Theses and Dissertations

The underlying physics of failure are critical in assessing the long term reliability of power packages in their intended field applications, yet traditional reliability determination methods are largely inadequate when considering thermomechanical failures. With current reliability determination methods, long test durations, high costs, and a conglomerate of concurrent reliability degrading threat factors make effective understanding of device reliability difficult and expensive. In this work, an alternative reliability testing apparatus and associated protocol was developed to address these concerns; targeting rapid testing times with minimal cost while preserving fatigue life prediction accuracy. Two test stands were fabricated to evaluate device reliability …

High Performance Distributed On-Chip Voltage Regulation For Modern Integrated Systems, Longfei Wang

USF Tampa Graduate Theses and Dissertations

Distributed on-chip voltage regulation where multiple voltage regulators are distributed among different locations of the chip demonstrates advantages as compared to on-chip voltage regulation utilizing a single voltage regulator. Better on-chip voltage noise performance and faster transient response can be realized due to localized voltage regulation. Despite the advantages of distributed on-chip voltage regulation, unbalanced current sharing issue can occur among each voltage regulator, which has been demonstrated to deteriorate power conversion efficiency, stability, and reliability of the power delivery network. An effective balanced current sharing scheme that can be applied to most voltage regulator types is proposed to balance …

An Overview Of Direct Current Distribution System Architectures & Benefits, Venkata Anand Prabhala, Bhanu Prashant Baddipadiga, Poria Fajri, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines existing and future direct current (DC) distribution systems with a wide range of applications in data centers, telecommunication systems, commercial buildings, residential homes, electric vehicles, spacecraft, and aircrafts. DC distribution systems have many advantages and disadvantages over their alternating current (AC) counterparts. There are a few surviving examples of DC distribution systems; among them are the telecommunication systems and data centers that use the low-voltage 48 Vdc systems. However, recently, there has been a move towards higher DC bus voltages. In this paper, a comparative study of different DC distribution architectures and bus structures is presented and …

Novel Representations For A Coherent Threshold Reliability System: A Tale Of Eightsignal Ow Graphs, Ali Muhammad Rushdi, Alaa Mohammad Alturki

Turkish Journal of Electrical Engineering and Computer Sciences

A threshold system is a reliability system whose success/failure is a threshold switching function in the successes/failures of its components. A coherent system (CS) is one that is causal, monotone, and with relevant components. The coherent threshold system (CTS), typically called the weighted k-out-of-n system, is consequently described by strictly positive weights and threshold. This paper presents recursive relations as well as boundary conditions for eight entities pertaining to a CTS. These are (a) expressions of monoform literals as well as disjoint or probability- ready expressions for either system success or failure, and (b) all-additive formulas as well as inclusion-exclusion …

Reliable Data Gathering In The Internet Of Things Using Artificial Bee Colony, Samad Najjar-Ghabel, Shamim Yousefi, Leili Farzinvash

Turkish Journal of Electrical Engineering and Computer Sciences

The Internet of Things (IoT) technology enables physical devices to communicate with each other for preparing, gathering, and sharing hazard warnings or critical information without human intervention. With respect to emergency applications of IoT technology, an essential issue is to provide an efficient and robust scheme for data gathering. The proposed solution in the existing approaches is to construct a spanning tree over the IoT devices and collect data using the tree. The shortcoming of these algorithms is that they do not take into account the probability of device mobility or failure. In such cases, the spanning tree is split, …

Screen Printing Silver Stretchable Conductive Paste To High Density Synthetic Fabric, Allison Rose Tuuri, Wesley Graham Powell

Materials Engineering

This project investigated the viability of screen printing stretchable silver conductive paste directly onto fabric and how the resistance changed under cyclic mechanical loading. The paste tested was DuPont™ PE873 stretchable silver conductive paste, which forms a stretchable conductive path by suspending silver flakes in elastomer that can be elastically strained along with the underlying substrate. The silver pastes were printed directly onto two different high-density synthetic fabrics of different weaves. Other samples were prepared by first printing a base layer between the silver paste and the fabric. One base layer was a solvent-based dielectric (DuPont™ ME776) and a stretchable …

Using On-Chip Error Detection To Estimate Fpga Design Sensitivity To Configuration Upsets, Andrew Mark Keller

Theses and Dissertations

SRAM-based FPGAs provide valuable computation resources and reconfigurability; however, ionizing radiation can cause designs operating on these devices to fail. The sensitivity of an FPGA design to configuration upsets, or its SEU sensitivity, is an indication of a design's failure rate. SEU mitigation techniques can reduce the SEU sensitivity of FPGA designs in harsh radiation environments. The reliability benefits of these techniques must be determined before they can be used in mission-critical applications and can be determined by comparing the SEU sensitivity of an FPGA design with and without these techniques applied to it. Many approaches can be taken to …

High-Speed Programmable Fpga Configuration Memory Access Using Jtag, Ammon Bradley Gruwell

Theses and Dissertations

Over the past couple of decades Field Programmable Gate Arrays (FPGAs) have become increasingly useful in a variety of domains. This is due to their low cost and flexibility compared to custom ASICs. This increasing interest in FPGAs has driven the need for tools that both qualify and improve the reliability of FPGAs for applications where the reconfigurability of FPGAs makes them vulnerable to radiation upsets such as in aerospace environments. Such tools ideally work with a wide variety of devices, are highly programmable but simple to use, and perform tasks at relatively high speeds. Of the various FPGA configuration …

Fast And Efficient Radio Resource Allocation In Dynamic Ultra-Dense Heterogeneous Networks, Chonggyu Niu, Yibing Li, Rose Qingyang Hu, Fang Ye

Electrical and Computer Engineering Faculty Publications

Ultra-dense network (UDN) is considered as a promising technology in 5G wireless networks. In an UDN network, dynamic traffic patterns can lead to a high computational complexity and an excessive communications overhead with traditional resource allocation schemes. In this paper, a new resource allocation scheme presenting a low computational overhead and a low subband handoff rate in a dynamic ultra-dense heterogeneous network is presented. The scheme first defines a new interference estimation method that constructs network interference state map, based on which a radio resource allocation scheme is proposed. The resource allocation problem is a MAX-K cut problem and can …

Designing A Regulatory Framework For Efficient Integration Of Distributed Generation Technologies, Mohammad Jooshaki, Ali Abbaspour, Mahmud Fotuhi Firuzabad, Moein Moeini-Aghtaie

Turkish Journal of Electrical Engineering and Computer Sciences

This paper focuses on the designing procedure of a regulatory framework in distribution networks with the main goal being to facilitate the integration of distributed generation (DG) units. The proposed framework is based on the concept of the reward penalty scheme (RPS) and creates effective financial incentives for distribution companies (DISCOs) in improving the quality of their services by applying DG units. To achieve this goal, reliability indices and annual energy losses of a distribution network are considered as two significant measures used in designing the structure of several RPSs. Employing these schemes, the regulators can quantify the quality of …

Design Optimization Of A ĆUk Dc/Dc Converter Based On Reliability Constraints, Amirreza Zarrin Gharehkoushan, Mehdi Abapour, Amir Farakhor

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, power electronic converters have widely been used in various applications. This has led to concerns about the reliability of power converters and, as a result, their optimal design has attracted a lot of attention. However, the reliability-based optimal design of the Ćuk DC-DC converter has not yet been studied. A new methodology is presented here for the optimal design of the Ćuk converter based on reliability constraints. In this study, the converter is designed to minimize power losses in order to maximize the mean time to failure of the converter. A genetic algorithm is used as the optimization technique, …