Electrical and Computer Engineering Commons^™

Excellent Surface Passivation For High Efficiency C_Si Solar Cells, Sara Bakhshi

Electronic Theses and Dissertations

Semiconductor surface clean is sometimes perceived as costly but long recognized as pivotal in determining the final semiconductor device performance and yield. In this contribution, we investigated the effectiveness of crystalline silicon surface cleaning by a simple UV-ozone process in comparison to the industry standard RCA clean for silicon photovoltaic applications. We present a unique method of processing the silicon surface effectively by UV-ozone cleaning. Despite being simple, UV-ozone cleaning results in a superior surface passivation quality that is comparable to high-quality RCA clean. When used as a stack dielectric—UV-ozone oxide overlaid by aluminum oxide—the thickness of UV-ozone oxide plays …

Customizable Phased Array Antenna Using Reconfigurable Antenna Elements, Mahmoud Shirazi

Electronic Theses and Dissertations

A shared-aperture reconfigurable slot-ring antenna array switching between different frequency bands and polarizations is presented for phased array applications. PIN diode switches are incorporated into the slots of the antenna to change the state of the reconfigurable slot-ring antenna array. Each frequency band has its own feeding lines which allows for the use of high-performance narrow-band transmit/receive (T/R) modules instead of ultra wideband (UWB) T/R modules. Furthermore, the spacing between the elements in each frequency band is less than half free-space wavelength (λ0) over the frequency band of operation which enables grating-lobe-free beam scanning. This is the first shared-aperture reconfigurable …

Design And Implementation Of Pv-Firming And Optimization Algorithms For Three-Port Microinverters, Mahmood Alharbi

Electronic Theses and Dissertations

With the demand increase for electricity, the ever-increasing awareness of environmental issues, coupled with rolling blackouts, the role of renewable energy generation is increasing along with the thirst for electricity and awareness of environmental issues. This dissertation proposes the design and implementation of PV-firming and optimization algorithms for three-port microinverters. Novel strategies are proposed in Chapters 3 and 4 for harvesting stable solar power in spite of intermittent solar irradiance. PV firming is implemented using a panel-level three-port grid-tied PV microinverter system instead of the traditional high-power energy storage and management system at the utility scale. The microinverter system consists …

Design Of High Efficiency Brushless Permanent Magnet Machines And Driver System, Chengyuan He

Electronic Theses and Dissertations

The dissertation is concerned with the design of high-efficiency permanent magnet synchronous machinery and the control system. The dissertation first talks about the basic concept of the permanent magnet synchronous motor (PMSM) design and the mathematics design model of the advanced design method. The advantage of the design method is that it can increase the high load capacity at no cost of increasing the total machine size. After that, the control method of the PMSM and Permanent magnet synchronous generator (PMSG) is introduced. The design, simulation, and test of a permanent magnet brushless DC (BLDC) motor for electric impact wrench …

Analog Temperature Control Circuit For A Thin-Film Piezoelectric-On-Substrate Microelectromechanical Systems Oscillator, Heather Hofstee

Honors Undergraduate Theses

The objective and motivation for this project is to design a low-power, low-noise oven-control circuit to optimize the stability of a MEMS oscillator. MEMS oscillators can be fabricated using conventional semiconductor manufacturing methods and can often be assembled in packages smaller than those of traditional crystal oscillators. However, one of their largest disadvantages currently is their high temperature coefficient of frequency (TCF), causing MEMS oscillators to be especially sensitive to temperature changes. Hence, this project focuses on designing a printed circuit board that will allow the user to manually tune a current passing through a resonator wire-bonded to the board …

Processing Of Cubic Stabilized Zirconia Electrolyte Membranes For Electrolyte-Supported Single Cell Solid Oxide Fuel Cells Using Tape Casting, Arturo Coronado Rodriguez

Honors Undergraduate Theses

Electrochemical conversion devices are a developing technology that prove to be a viable and more efficient alternative to current environmentally friendly generation devices. As such, constant research has been done in the last few decades to increase their applications and reliability. One of these systems, and the focus of this research, is the single cell Solid Oxide Fuel Cell (SOFC). These systems are a developing technology which main caveat is the need of high operating temperatures and costs. As such, most multidisciplinary research has been focused on researching materials and/or processes that help mitigate the costs or lower the operating …

Robust, Scalable, And Provable Approaches To High Dimensional Unsupervised Learning, Mostafa Rahmani

Electronic Theses and Dissertations

This doctoral thesis focuses on three popular unsupervised learning problems: subspace clustering, robust PCA, and column sampling. For the subspace clustering problem, a new transformative idea is presented. The proposed approach, termed Innovation Pursuit, is a new geometrical solution to the subspace clustering problem whereby subspaces are identified based on their relative novelties. A detailed mathematical analysis is provided establishing sufficient conditions for the proposed method to correctly cluster the data points. The numerical simulations with both real and synthetic data demonstrate that Innovation Pursuit notably outperforms the state-of-the-art subspace clustering algorithms. For the robust PCA problem, we focus on …

Design Of Low-Capacitance Electrostatic Discharge (Esd) Protection Devices In Advanced Silicon Technologies., Aihua Dong

Electronic Theses and Dissertations

Electrostatic discharge (ESD) related failure is a major IC reliability concern and this is particularly true as technology continues shrink to nano-metric dimensions. ESD design window research shows that ESD robustness of victim devices keep decreasing from 350nm bulk technology to 7nm FinFET technologies. In the meantime, parasitic capacitance of ESD diode with same It2 in FinFET technologies is approximately 3X compared with that in planar technologies. Thus transition from planar to FinFET technology requires more robust ESD protection however the large parasitic capacitance of ESD protection cell is problematic in high-speed interface design. To reduce the parasitic capacitance, a …

Macro, Meso And Micro Perspectives Of Technology Transfer, James A. Cunningham, Paul O'Reilly

Conference Papers

Over the last few decades research into the different aspects of technology transfer has grown significantly that has taken in the main a macro perspective. This research has created a body of knowledge and an evidence base that has contributed original insights in developing the field and also has shaped policymaking and practice. Within the field there is a growing focus on meso and micro aspects of technology transfer and a growing interest in for example role individual actors such as scientists, principal investigators policy makers, TTO actors, supporting institutions and functions such as universities, professional research organizations, technology and …

Highly Sensitive Twist Sensor Based On Partially Silver Coated Hollow Core Fiber Structure, Dejun Liu, Rahul Kumar, Fangfang Wei, Wei Han, Arun Mallik, Jinhui Yuan, Chongxiu Yu, Feng Li, Zhengyong Liu, Hwa-Yaw Tam, Gerald Farrell, Yuliya Semenova, Qiang Wu

Articles

Interferometer based on multiple beam interferences inside a hollow core fiber (HCF) structure (also known as an antiresonant reflecting optical waveguide) has been attracting interest of many researchers due to its periodic transmission spectrum containing high quality factor spectral dips. Functionalized HCF structures have been demonstrated for a wide range of applications in humidity, magnetic field, and biosensing. Here, we report a new application of the HCF-based structure with a partial silver coating layer for sensing of twist. It is configured by a fusion splicing a section of 4.5-mm long HCF between two standard single mode fibers (SMFs), followed by …

A Novel Framework For Collaborative Intrusion Detection For M2m Networks, Mohammad Abdellatif, Junaid Arshad, Muhammad Azad, Muhammad Khan

Electrical Engineering

The proliferation of sensor devices has introduced exciting possibilities such as the Internet of Things (IoT). Machine to Machine (M2M) communication underpins efficient interactions within such infrastructures. The resource constraints and ad-hoc nature of these networks have significant implications for security in general and with respect to intrusion detection in particular. Consequently, contemporary solutions mandating a stable infrastructure are inadequate to fulfill these defining characteristics of M2M networks. In this paper, we present COLIDE (COLlaborative Intrusion Detection Engine) a novel framework for effective intrusion detection in the M2M networks without incurring high energy and communication cost on the participating host …

Colide: A Collaborative Intrusion Detection Framework For Internet Of Things, Mohammad Abdellatif, Junaid Arshad, Muhammad Ajmal Azad, Khaled Salah, Muhammad Habib Ur Rahman

Electrical Engineering

Internet of Things (IoT) represent a network of resource-constrained sensor devices connected through the open Internet, susceptible to misuse by intruders. Traditional standalone intrusion detection systems (IDS) are tasked with monitoring device behaviours to identify malicious activities. These systems not only require extensive network and system resources but also cause delays in detecting a malicious actor due to unavailability of a comprehensive view of the intruder's activities. Collaboration among IoT devices enables considering knowledge from a collection of host and network devices to achieve improved detection accuracy in a timely manner. However, collaboration introduces the challenge of energy efficiency and …

Supercapacitor Utilization For Power Smoothening And Stability Improvement Of Ahybrid Energy System In A Weak Grid Environment, Rahul Sharma, Sathans Suhag

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel control scheme based on the application of a supercapacitor (SC) is proposed for power smoothening and stability improvement of a hybrid energy system (HES) in weak grid conditions. The basic property of fast charging/discharging of the SC is utilized to design the proposed control. In weak grid conditions, the control structure is proposed for power smoothening and DC link voltage regulation with the help of the SC. Moreover, the stability is increased, ripples in voltage are reduced, there is fast dynamic response, and oscillations are damped out under different conditions. In conventional control, voltage controller …

Interactive Process Miner: A New Approach For Process Mining, İsmai̇l Yürek, Derya Bi̇rant, Kökten Ulaş Bi̇rant

Turkish Journal of Electrical Engineering and Computer Sciences

Process mining is a technique for extracting knowledge from event logs recorded by an information system. In the process discovery phase of process mining, a process model is constructed to represent the business processes systematically and to give a general opinion about the progressive of processes in the event log. The constructed process model can be very complex as a result of structured and unstructured processes recorded in real life. Previous studies proposed different approaches to filter or eliminate some processes from the model to simplify it by implementing some statistical or mathematical formulas rather than user interactions. The main …

An Integrated Approach For The Development Of An Electric Vehicle Powertrain: Design, Analysis, And Implementation, Özgür Üstün, Ramazan Nejat Tuncay, Mert Safa Mökükcü, Ömer Ci̇han Kivanç, Gürkan Tosun, Can Gökce, Murat Çakan

Turkish Journal of Electrical Engineering and Computer Sciences

Electric motor and power electronic systems are essential elements for the performance and efficiency of electric vehicles (EVs) and hybrid electric vehicles. The inadequacy of the range due to battery limitations is compensated by powertrain solutions and innovative control algorithms. Future targets of electric powertrains are mostly based on weight, space, and efficiency issues. Highly efficient low-volume and light-weight propulsion systems increase the performance of EVs and also enhance their importance as an alternative to internal combustion engine vehicles. In this paper, a detailed propulsion system design study is presented by considering all of the important constraints of the electric …

Model Predictive Control Of A Dual Induction Motor Drive Fed By A Single Voltage Source Inverter, Muhammad Abbas Abbasi, Abdul Rashid Bin Husain

Turkish Journal of Electrical Engineering and Computer Sciences

In dual induction motor control applications, averaging of controlled variables, mean circuit models, or master/slave strategies are used, which lead to unbalanced and unstable operation of the overall drive system. An improved finite control set predictive torque control (FCS-PTC) method is proposed for the parallel operation of two induction motors. The optimization cost function of the controller is shown to meet multiple objectives simultaneously, eliminating the use of averaging techniques and without leading to unbalanced conditions. The simulation results are compared with direct torque control (DTC) for dual induction motors. As compared to DTC, model predictive control shows low torque …

Research On Power-Frequency Electromagnetic Interference Model Of Multicore Twisted Signal Cable Of High-Speed Railway, Bowen Zhang, Jiangjian Xie, Zhixin Wang, Jin Yang, Hao Yan

Turkish Journal of Electrical Engineering and Computer Sciences

With the increase in the traction power of high-speed railways, the power-frequency electromagnetic interference of traction current to the signal cables becomes increasingly more severe. In this paper, the calculation model of the magnetic interference to signal cable was established on the MATLAB/Simulink platform based on the multiconductor transmission line theory. This model took SPTYWPL03-8B 8-core twist signal cable as an example and the power-frequency interference of external current to the signal cable was analyzed theoretically. In addition, experiments on electromagnetic interference of double-ended and single-ended signal cables were performed to validate the simulation model. Experiments showed that the relative …

Real-Time Implementation Of Three-Level Inverter-Based D-Statcom Using Neuro-Fuzzy Controller, Resul Çöteli̇, Hakan Açikgöz, Beşi̇r Dandil, Servet Tuncer

Turkish Journal of Electrical Engineering and Computer Sciences

A distribution static compensator (D-STATCOM) is a custom power device connected in parallel to a power system to address electric power quality problems caused by reactive power and harmonics. To obtain high performance from a D-STATCOM, the D-STATCOM's \textit{dq}-axis currents must be controlled in an internal control loop. However, control of the D-STATCOM's currents is difficult because of its nonlinear structure, cross-coupling effect between the \textit{d}- and \textit{q}-axis, undefined dynamics, and fast changing load. Therefore, the controller to be preferred for a D-STATCOM should have a nonlinear and robust structure. In this study, a neuro-fuzzy controller (NFC), which is a …

Large Vocabulary Recognition For Online Turkish Handwriting With Sublexical Units, Esma Fatima Bi̇lgi̇n Taşdemi̇r, Ayşe Berri̇n Yanikoğlu Yeşi̇lyurt

Turkish Journal of Electrical Engineering and Computer Sciences

We present a system for large vocabulary recognition of online Turkish handwriting, using hidden Markov models. While using a traditional approach for the recognizer, we have identified and developed solutions for the main problems specific to Turkish handwriting recognition. % First, since large amounts of Turkish handwriting samples are not available, the system is trained and optimized using the large UNIPEN dataset of English handwriting, before extending it to Turkish using a small Turkish dataset. % The delayed strokes, which pose a significant source of variation in writing order due to the large number of diacritical marks in Turkish, are …

Fundamental Efficiency Limit Of Passive Non-Magnetic Self-Interference Suppression In Full-Duplex Radios, Adam Narbudowicz, Giuseppe Ruvio, Max Ammann, Nicola Marchetti

Conference Papers

Passive non-magnetic self-interference suppression circuits are currently used as first stages of complex full-duplex radio systems that allow simultaneous reception and transmission within the same channel. This paper introduces the upper efficiency limit for such circuitry. It is demonstrated that for these devices it is not feasible to have simultaneously high efficiency, good transmitter-to-receiver isolation and same propagation channel for transmission and reception. More specifically, the maximum efficiency for most typical case cannot exceed 50% if good isolation is obtained.

Ses And Ecore For Ontology-Based Scenario Modeling In Aviation Scenario Definition Language (Asdl), Shafagh Jafer, Bharvi Chhaya, Bernard P. Zeigler, Umut Durak

International Journal of Aviation, Aeronautics, and Aerospace

The Aviation Scenario Definition Language (ASDL) is a domain-specific language proposal which aims to provide a standard aviation scenario specification mechanism and enable the reuse of scenario generation methods among different simulators. This paper presents a model-based scenario development approach that exploits Eclipse Modeling Framework (EMF) core (Ecore) and System Entity Structure (SES) for metamodeling and modeling these elements. The construction of the ASDL metamodel using both platforms is described to illustrate the processes. As a result of comparing two approaches, it is concluded that they follow a similar structure in the hierarchical definition of modeled elements despite there being …

Control Of Gas Metal Arc Welding Using Process Sensing And Laser Arc Stabilization For Additive Manufacturing, Dale Brush

Graduate Theses & Non-Theses

The goal of the present research was to bridge the gap between powder-based and wire-based additive manufacturing (AM) processes using gas metal arc welding (GMAW). Powder-based AM processes typically can produce components with high geometric resolution (small features), but at low deposition rates. Wire-based AM processes typically can produce components with low geometric resolution, but at high deposition rates. AM with GMAW is a wire-based AM process in the wire arc additive manufacturing (WAAM) category of AM. To bridge the gap between powder-based and wire-based AM processes, GMAW’s deposition rate has to be reduced, allowing small features to be built. …

Highly Sensitive Displacement Sensor Based On Composite Interference Established Within A Balloon-Shaped Bent Multimode Fiber Structure, Ke Tian, Gerald Farrell, Xianfan Wang, Elfed Lewis, Pengfei Wang

Articles

A novel optical fiber displacement sensor based on composite interference established within a balloon-shaped bent multimode (BSBM) fiber structure is described and experimentally demonstrated. The BSBM fiber structure is realized by bending a straight single-mode–multimode–single-mode (SMS) fiber structure into a balloon shape using a length of capillary tube to fix the shape of the structure. Owing to the bend in the multimode waveguide, the original undistorted multimode interference pattern is changed, and an extra Mach–Zehnder interferometer is effectively introduced within the multimode fiber (MMF) section at a suitable bending radius. This established composite interference greatly improves the displacement sensing performance …

Developing A Methodology For Estimating The Growth Of Radiated Emission From Multi-Modular Systems, Kaustav Ghosh

Masters Theses

"The large multiscale problems are commonly faced in real-world applications such as analysis of electromagnetic interference for a printed circuit board installed on a large platform with connected cables, wires and other high speed interfaces. EMI problems are not uncommon in high speed systems which involve multiple modules of complex hardware. As the system clock frequency and data rate increases, so does the challenges in controlling the EMI in such systems. The costs to prototype and to develop networking equipment are growing as a result of increasing complexities and densities. EMC regulations require radiated emission testing to be done in …

Analysis Of Dc Microgrids As Stochastic Hybrid Systems, Jacob Andreas Mueller

Doctoral Dissertations

"A modeling framework for dc microgrids and distribution systems based on the dual active bridge (DAB) topology is presented. The purpose of this framework is to accurately characterize dynamic behavior of multi-converter systems as a function of exogenous load and source inputs. The base model is derived for deterministic inputs and then extended for the case of stochastic load behavior. At the core of the modeling framework is a large-signal DAB model that accurately describes the dynamics of both ac and dc state variables. This model addresses limitations of existing DAB converter models, which are not suitable for system-level analysis …

A Machine Learning Approach For Power Allocation In Hetnets Considering Qos, Roohollah Amiri, Hani Mehrpouyan, Lex Fridman, Ranjan K. Mallik, Arumugam Nallanathan, David Matolak

Electrical and Computer Engineering Faculty Publications and Presentations

There is an increase in usage of smaller cells or femtocells to improve performance and coverage of next-generation heterogeneous wireless networks (HetNets). However, the interference caused by femtocells to neighboring cells is a limiting performance factor in dense HetNets. This interference is being managed via distributed resource allocation methods. However, as the density of the network increases so does the complexity of such resource allocation methods. Yet, unplanned deployment of femtocells requires an adaptable and self-organizing algorithm to make HetNets viable. As such, we propose to use a machine learning approach based on Q-learning to solve the resource allocation …

Hybrid Inductive Power Transfer And Wireless Antenna System For Biomedical Implanted Devices, Reem Shadid, Mohammad Haerinia, Sayan Roy, Sima Noghanian

Electrical Engineering Faculty Publications

In this paper, we present a hybrid system consisting of a novel microstrip antenna that can be designed to resonate at various frequencies within the ultra-high frequency (UHF) band (e.g., 415 MHz, 905 MHz, and 1300 MHz), combined with a pair of high frequency (HF) coils (13.56 MHz). The system is designed to be fabricated on an FR4 substrate layer, and it provides a compact solution for simultaneous wireless power transfer (WPT) and multi-band wireless communication, to be utilized in implanted medical devices. The external antenna/coil combination (EX) will be located outside the body on the skin layer. The EX …

Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella

Browse all Theses and Dissertations

In this project, we continue previous CSR project entitled RF Steganography based Joint Radar/Communication Waveform Design to develop a bio-inspired secure low probability detection (LPD) radio frequency (RF) waveform that can serve multiple purposes simultaneously. Previously, we have developed an RF steganography based RF waveform to conceal a secure digital communication within a linear frequency modulated (LFM) chirp radar signal. By exploiting novel reduced phase shift keying modulation and variable symbol duration, the new waveform is resistant to time domain analysis, frequency domain analysis and cyclostationary analysis. However, to demodulate the hidden communication message, the intended receiver has to know …

Threshold-Based Distributed Ddos Attack Detection In Isp Networks, Karanbir Singh, Kanwalvir Singh Dhindsa, Bharat Bhushan

Turkish Journal of Electrical Engineering and Computer Sciences

The purpose of this paper is to propose a more efficient and accurate distributed denial of service (DDoS) attack detection mechanism that detects DDoS attacks by monitoring the incoming traffic on the edge routers of ISP networks. It can be implemented as a module or agent function on the machine that is responsible for processing router traffic. The detection algorithm works by monitoring the traffic passing through the edge routers and identifying the occurrence of DDoS attacks or flash events. The algorithm calculates different values like the normalized router entropy, packet rate, and entropy rate and compares them against the …

Static Optimization Of Fuel Cell Plug-In Hybrid Electric Vehicle, Sunday Julius Balogun

Graduate Research Theses & Dissertations

This thesis focuses on the static optimization of a fuel cell plug-in hybrid electric vehicle. The vehicle is been powered by three (3) sources of electrical energy. These sources of electrical energy are: fuel cell, supercapacitor, and lithium-ion battery.

The main target of this thesis is to make good the performance of a fuel cell plug-in hybrid electric vehicle. This will be achieved by applying static optimization method on the dynamic equations of a moving hybrid vehicle.

The optimization model of this plug-in hybrid electric vehicle (PHEV) was formulated bases on multiple objectives. The objective parameters are: cost, volume, and …