Electrical and Electronics Commons^™

Hydrophobic Surface Modification Of Polymethyl Methacrylate By Two-Dimensional Plasma Jet Array At Atmospheric Pressure, Feng Liu, Meiling Cai, Bo Zhang, Zhi Fang, Chunqi Jiang, Kostya Ken Ostrikov

Bioelectrics Publications

Recently developed atmospheric pressure plasma jet (APPJ) is considered as a novel and efficient technique for uneven surfaces processing and APPJ array effectively expands the treatment area of a single APPJ. In this paper, a two-dimensional (2D) APPJ array in Ar/tetramethylsilane (TMS) is used to improve the surface hydrophobicity of polymethyl methacrylate (PMMA) by depositing polymerized silicalike clusters on the jet-PMMA interface. The electrical and optical characteristics of the 2D Ar/TMS APPJ array are measured to optimize experimental conditions. The wettability of jet-PMMA interface is assessed by measuring water contact angle, which increases from 65° to a maximum value of …

Design Of Fusion-Based Underwater Image Enhancement Method In Video Stream, Pann Mya Hmue

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis has designed a fusion-based enhancement method for underwater images and video streams which are mainly distorted by color changes, poor illumination, and water particles. The main objective of image fusion is to achieve a comprehensive result which is appropriate for the human visual system. In this thesis, our goal is to use a straight forward and not computationally intensive reconstruction. As a result, the underwater images or video streams are partially restored from the original ones. Firstly, the 5.8 GHz transmitter and receiver set are used to carry the input data from the camera which is placed inside …

Silica Gel Coated Spherical Micro Resonator For Ultra-High Sensitivity Detection Of Ammonia Gas Concentration In Air, Arun Mallik, Gerald Farrell, Dejun Liu, Vishnu Kavungal, Qiang Wu, Yuliya Semenova

Articles

A silica gel coated microsphere resonator is proposed and experimentally demonstrated for measurements of ammonia (NH3) concentration in air with ultra-high sensitivity. The optical properties of the porous silica gel layer change when it is exposed to low (parts per million (ppm)) and even ultra-low (parts per billion (ppb)) concentrations of ammonia vapor, leading to a spectral shift of the WGM resonances in the transmission spectrum of the fiber taper. The experimentally demonstrated sensitivity of the proposed sensor to ammonia is estimated as 34.46 pm/ppm in the low ammonia concentrations range from 4 ppm to 30 ppm using an optical …

Radiation Effects In Tantalum Oxide-Based Resistive Memory Devices, Joshua Stuart Holt

Legacy Theses & Dissertations (2009 - 2024)

There is an increasing need for radiation-hardened electronics as space programs grow in number and scope. Scientific interest in long-term exploration, particularly in high-radiation environments such as Europa, as well as commercial interest in establishing permanent outposts, requires high tolerance of radiation effects. A flash memory device might survive for several years in low Earth orbit, but only a few days in orbit around Europa due to the extremely high levels of radiation encountered there. Meanwhile, commercial interests, including asteroid mining and building a base on the moon or Mars would require electronic systems that could survive for long periods …

Voltage Regulation Of Unbalanced Distribution Network With Distributed Generators Through Genetic Algorithm, Islam Ali

Dissertations and Theses @ UNI

Energy demand has rapidly increased since the manufacturing revolution in the 19th century. One of the higher energy demands is electricity. The great majority of devices in the manufacturing field run on electricity. The vertically integrated grid paradigm has to be changed to supply the increase in the electrical demand residentially and commercially. Distributed generators (DG) such as Photovoltic (PV) is used to supply the increase in the electrical demand. Photovoltaic (PV) is one of the fast growing distributed generators (DG) as a renewable energy source. However, installing many PV systems to the distribution system can cause power quality problems …

Cryogenic Probe Station At Old Dominion University Center For Accelerator Science, Junki Makita, Jean R. Delayen, Alex Gurevich, Gianluigi Ciovati

Physics Faculty Publications

With a growing effort in research and development of an alternative material to bulk Nb for a superconducting radiofrequency (SRF) cavity, it is important to have a cost effective method to benchmark new materials of choice. At Old Dominion University's Center for Accelerator Science, a cryogenic probe station (CPS) will be used to measure the response of superconductor samples under RF fields. The setup consists of a closed-cycle refrigerator for cooling a sample wafer to a cryogenic temperature, a superconducting magnet providing a field parallel to the sample, and DC probes in addition to RF probes. The RF probes will …

ระบบควบคุมเวกเตอร์แบบไร้เซนเซอร์วัดตำแหน่งสำหรับเครื่องจักรกลไฟฟ้าเหนี่ยวนำชนิดป้อนสองทางโดยใช้ตัวสังเกตลดอันดับแบบปรับตัวที่มีการป้อนกลับกระแสสเตเตอร์, ศุภษร หมื่นพล

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์นี้นำเสนอระบบควบคุมเวกเตอร์ไรเซนเซอร์วัดตำแหน่งสำหรับเครื่องจักรกลไฟฟ้าเหนี่ยวนำชนิดป้อนสองทาง โดยใช้ตัวสังเกตลดอันดับแบบปรับตัวจากแบบจำลองสเตเตอร์ แนวคิดที่นำเสนอมีการคำนวณที่เรียบง่ายไม่ซับซ้อน และไม่จำเป็นต้องคำนวณค่าปริพันธ์ของสเตเตอร์ฟลักซ์ ทำให้ลดปัญหาเรื่องการเลื่อนของสัญญาณไฟตรงได้ การวิเคราะห์เสถียรภาพของแบบจำลองในวิทยานิพนธ์นี้ใช้วิธีการทำให้ระบบเป็นเชิงเส้นและใช้ทฤษฎีบทเราท์-เฮอร์วิตช์ยืนยันเสถียรภาพของระบบรอบ ๆ จุดทำงาน นอกจากนี้ยังนำเสนอแนวทางการออกแบบอัตราขยายป้อนกลับและอัตราขยายป้อนกลับแบบปรับตัวสำหรับตัวประมาณตำแหน่ง เพื่อใช้เป็นแนวทางในการออกแบบตัวควบคุม อีกทั้งเสนอการวิเคราะห์ผลกระทบของการประมาณตำแหน่งเนื่องจากการเปลี่ยนแปลงค่าพารามิเตอร์ต่าง ๆ ของเครื่องจักรกลไฟฟ้าเหนี่ยวนำชนิดป้อนสองทาง และสุดท้ายนี้เพื่อเป็นการยืนยันแนวคิดทางทฤษฎีโดยการจำลองผลด้วยโปรแกรม Matlab/Simulink และการทดสอบด้วยระบบจริง โดยระบบควบคุมเวกเตอร์ไรเซนเซอร์วัดตำแหน่ง สามารถทำงานได้ทุกเงื่อนไขการทำงาน และสามารถควบคุมกระแสโรเตอร์ได้อย่างอิสระสอดคล้องหลักการการควบคุมแบบแยกการเชื่อมร่วม

Electrowetting Using A Microfluidic Kelvin Water Dropper, Elias Yazdanshenas, Qiang Tang, Xiaoyu Zhang

Mechanical & Aerospace Engineering Faculty Publications

The Kelvin water dropper is an electrostatic generator that can generate high voltage electricity through water dripping. A conventional Kelvin water dropper converts the gravitational potential energy of water into electricity. Due to its low current output, Kelvin water droppers can only be used in limited cases that demand high voltage. In the present study, microfluidic Kelvin water droppers (MKWDs) were built in house to demonstrate a low-cost but accurately controlled miniature device for high voltage generation. The performance of the MKWDs was characterized using different channel diameters and flow rates. The best performed MKWD was then used to conduct …

Assessing The Spatial Accuracy And Precision Of Lidar For Remote Sensing In Agriculture, Surya Saket Dasika

Theses and Dissertations--Biosystems and Agricultural Engineering

The objective of this whole study was to evaluate a LiDAR sensor for high-resolution remote sensing in agriculture. A linear motion system was developed to precisely control the dynamics of LiDAR sensor in effort to remove uncertainty in the LiDAR position/velocity while under motion. A user control interface was developed to operate the system under different velocity profiles and log LiDAR data synchronous to the motion of the system. The LiDAR was then validated using multiple test targets with five different velocity profiles to determine the effect of sensor velocity and height above a target on measurement error. The results …

Contributions To Hybrid Power Systems Incorporating Renewables For Desalination Systems, Nasser Alawhali

Theses and Dissertations--Electrical and Computer Engineering

Renewable energy is one of the most reliable resource that can be used to generate the electricity. It is expected to be the most highly used resource for electricity generation in many countries in the world in the next few decades. Renewable energy resources can be used in several purposes. It can be used for electricity generation, water desalination and mining. Using renewable resources to desalinate the water has several advantages such as reduce the emission, save money and improve the public health. The research described in the thesis focuses on the analysis of using the renewable resources such as …

Electronic Drum Machine (E.D.M), Nyssa Marie Backes

Electrical Engineering

Many people argue that a drummer plays the most important role in a band of any genre. During live performances, the other band members rely on the drummer to keep the song moving forward at a proper steady pace. Even in recorded music, drums help listeners sing and dance along with their favorite songs. Thus, achieving success as a band, both in terms of recordings and live shows, absolutely requires a drummer. So, if a band does not have a drummer, and cannot afford the hefty cost of hiring a session drummer, a touring drummer, or both, how can they …

Artificial Neuron Using Mos2/Graphene Threshold Switching Memristor, Hirokjyoti Kalita

Electronic Theses and Dissertations

With the ever-increasing demand for low power electronics, neuromorphic computing has garnered huge interest in recent times. Implementing neuromorphic computing in hardware will be a severe boost for applications involving complex processes such as pattern recognition. Artificial neurons form a critical part in neuromorphic circuits, and have been realized with complex complementary metal–oxide–semiconductor (CMOS) circuitry in the past. Recently, insulator-to-metal-transition (IMT) materials have been used to realize artificial neurons. Although memristors have been implemented to realize synaptic behavior, not much work has been reported regarding the neuronal response achieved with these devices. In this work, we study the IMT in …

High Quality Gate Dielectric/Mos2 Interfaces Probed By The Conductance Method, Adithi Pandrahal Krishnaprasad Sharada

Electronic Theses and Dissertations

Two-dimensional materials provide a versatile platform for various electronic and optoelectronic devices, due to their uniform thickness and pristine surfaces. We probe the superior quality of 2D/2D and 2D/3D interfaces by fabricating molybdenum disulfide (MoS2)-based field effect transistors having hexagonal boron nitride (h-BN) and Al2O3 as the top gate dielectrics. An extremely low trap density of ~7x10^10 states/cm2-eV is extracted at the 2D/2D interfaces with h-BN as the top gate dielectric on the MoS2 channel. 2D/3D interfaces with Al2O3 as the top gate dielectric and SiOx as the nucleation layer exhibit trap densities between 7x10^10 and 10^11 states/cm2-eV, which is …

Monolithically Integrated Wavelength Tunable Laser Diode For Integrated Optic Surface Plasmon Resonance Sensing, Thamer Tabbakh

Electronic Theses and Dissertations

In this work, we demonstrate an InGaAsP multiple quantum well tunable laser diode that amalgamates two gain sections with different bandgap energies. This is achieved using selective area intermixing of the multiple quantum wells, and impurity-free vacancy induced disordering. When different current combination is injected into each section, that leads to a laser wavelength peak whose position depends on the relative magnitudes of the two injected currents. The laser wavelength can be fine-tuned from 1538 nm to 1578 nm with relatively constant output power. The free spectral range FSR of the tunable laser found to be 0.25 nm. This tunable …

Analysis Of High Performance Scientific Programming Workflows, Withana Kankanamalage Umayanganie Klaassen

Open Access Theses & Dissertations

Substantial time is spent on building, optimizing and maintaining large-scale software that is run on supercomputers. However, little has been done to utilize overall resources efficiently when it comes to including expensive human resources. The community is beginning to acknowledge that optimizing the hardware performance such as speed and memory bottlenecks contributes less to the overall productivity than does the development lifecycle of high-performance scientific applications. Researchers are beginning to look at overall scientific workflows for high performance computing. Scientific programming productivity is measured by time and effort required to develop, configure, and maintain a simulation experiment and its constituent …

On The Application Of Pspice For Localised Cloud Security, Paul Tobin

Doctoral

The work reported in this thesis commenced with a review of methods for creating random binary sequences for encoding data locally by the client before storing in the Cloud. The first method reviewed investigated evolutionary computing software which generated noise-producing functions from natural noise, a highly-speculative novel idea since noise is stochastic. Nevertheless, a function was created which generated noise to seed chaos oscillators which produced random binary sequences and this research led to a circuit-based one-time pad key chaos encoder for encrypting data. Circuit-based delay chaos oscillators, initialised with sampled electronic noise, were simulated in a linear circuit simulator …

Miniaturized Switchless Pattern Reconfigurable Antenna Utilizing Spherical Modes Analysis, Adam Narbudowicz, Max Ammann, Nicola Marchetti

Conference Papers

The paper proposes an electrically small pattern reconfigurable antenna, which allows flexible beamforming with the antenna diameter being ?/5. The antenna has 3 ports, each designed to radiate a different spherical mode. By applying appropriate phase shift the antenna allows to flexibly sweep its bi-directional radiation pattern across a 360° azimuth, while offering 5 dBi directivity.

Handwritten Bangla Character Recognition Using The State-Of-The-Art Deep Convolutional Neural Networks, Md Zahangir Alom, Paheding Sidike, Mahmudul Hasan, Tarek M. Taha, Vijayan K. Asari

Electrical and Computer Engineering Faculty Publications

In spite of advances in object recognition technology, handwritten Bangla character recognition (HBCR) remains largely unsolved due to the presence of many ambiguous handwritten characters and excessively cursive Bangla handwritings. Even many advanced existing methods do not lead to satisfactory performance in practice that related to HBCR. In this paper, a set of the state-of-the-art deep convolutional neural networks (DCNNs) is discussed and their performance on the application of HBCR is systematically evaluated. The main advantage of DCNN approaches is that they can extract discriminative features from raw data and represent them with a high degree of invariance to object …

The Different Stages Of Prpd Pattern For Positive Point To Plane Corona Driven By A Dc Voltage Containing A Ripple, Tobias Dezenzo, Thomas Betz, Andreas Schwarzbacher

Articles

The different phase resolved partial discharge patterns, which can be recognized when a positive dc voltage containing a ripple due to a half-wave rectification is used are presented in this paper. Results are given from corona onset to the appearance of breakdown streamers. The outcomes are five different patterns, which represent the four stages of positive corona and their transition zones. Three of them are clearly identifiable with respect to patterns from other discharge sources that have already been reported for dc voltages containing a ripple. For an assessment of pattern formation discharge pulses as recorded at the test object …

การวิเคราะห์ผลกระทบทางความร้อนต่ออายุการใช้งานของหม้อแปลง, ธิราดา เฉยสกุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์ฉบับนี้นำเสนอเกี่ยวกับการวิเคราะห์ผลกระทบทางความร้อนต่ออายุการใช้งานของหม้อแปลง ด้วยการใช้ข้อมูลการตรวจวัดพื้นฐาน ข้อมูลของหม้อแปลง และอุณหภูมิแวดล้อม เพื่อประเมินหาอุณหภูมิที่จุดร้อนสุดของขดลวด ทั้งในกรณีที่หม้อแปลงจ่ายโหลดที่เป็นเชิงเส้นและโหลดที่ไม่เป็นเชิงเส้น โดยพัฒนาวิธีการจาก IEEE Std. C57.91-2010 และ IEEE Std. C57.110-2018 รวมกัน ในการวิเคราะห์จะใช้หม้อแปลงกำลังชนิดแช่ในน้ำมัน ขนาด 50 MVA และข้อมูลการตรวจวัดด้วยมิเตอร์วัดคุณภาพไฟฟ้าจากสถานีไฟฟ้าย่อยปลวกแดง 1 จังหวัดระยอง เป็นเวลา 10 เดือน พร้อมทั้งศึกษาผลกระทบจากปัจจัยที่ทำให้ความร้อนในหม้อแปลงมีค่ามากขึ้น รวมไปถึงผลกระทบเมื่อมีระบบพลังงานแสงอาทิตย์ติดตั้งในระบบด้วยการจำลองในโปรแกรม DIgSILENT PowerFactory จากการวิเคราะห์พบว่า ระดับของโหลด กระแสฮาร์มอนิกส์ และอุณหภูมิแวดล้อม สามารถส่งผลกระทบด้านความร้อนต่อหม้อแปลงด้วยการเพิ่มอุณหภูมิที่จุดร้อนสุดของขดลวด ซึ่งหากอุณหภูมิที่จุดร้อนสุดของขดลวดมีค่ามากเกินกว่าข้อจำกัดจะทำให้อายุการใช้งานของหม้อแปลงลดลง แต่เมื่อมีการติดตั้งพลังงานแสงอาทิตย์ในขนาดที่เหมาะสมในระบบ จะสามารถช่วยลดอายุการใช้งานที่สูญเสียของหม้อแปลงได้ โดยปัจจัยที่ส่งผลกระทบด้านความร้อนต่อหม้อแปลงจากมากไปน้อย คือ ระดับของโหลด กระแสฮาร์มอนิกส์ และอุณหภูมิแวดล้อม ตามลำดับ

Ball Oscillating Bouncer, Eric Blok, Daniel Altemese, Ryan Nowacki, Maram Qurban

Williams Honors College, Honors Research Projects

The purpose of this report is to document the need, objectives, marketing and engineering requirements, as well as validate the design of an autonomous control device capable of continuously bouncing a table tennis ball on a paddle. This includes the design of a self correcting system using lightweight materials, and as few sensors and components as possible to achieve a compact, portable design. To accomplish this, the system is designed to react to a ball falling from as short a distance as 10 centimeters above the paddle, meaning all sensor processing, control processing, and motor drives should be able to …

Soil Moisture Sensor, Jaclyn Miller, Derek Bitecofer, Seung Jun Lee

Williams Honors College, Honors Research Projects

Since water is an important resource and not all communities around the world can afford to be liberal with their water needs; it has become important to use available water as efficiently as possible, especially in agriculture. For the purpose of reducing the overwatering of crops, an unattended ground moisture sensor can be implemented to measure the moisture level in the soil surrounding the plants. This will allow a farmer to know when to water or stop watering crops. For convenience, the moisture data information should be transmitted wirelessly to the user. The design of an unattended ground moisture sensor …

Quantitative Characterization Of Lithium-Ion Batteries Under Abuse Conditions, Xiaoniu Du

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Real-Time Image Pattern Sensor For Weld Pool Penetration Through Reflection In Gtaw, Yu-Ting Chen

Theses and Dissertations--Electrical and Computer Engineering

In gas tungsten arc welding (GTAW), weld pool surface contains crucial information for welding development. In this research, simulate skilled welders to control the welding process and determine the penetration stages based on the weld pool reaction.

This study focuses on solving the uncertainty of the liquid weld pool in joint bases. The weld pool penetration process is highly depending on how the weld pool surface shape. To observe the weld pool, reflect the weld pool surface by the laser and image on the shield glass. The experiments show that the penetration can’t be determine by the reflecting grayness due …

Design Of A Machine Vision Camera For Spatial Augmented Reality, Matt Phillip Ruffner

Theses and Dissertations--Electrical and Computer Engineering

Structured Light Imaging (SLI) is a means of digital reconstruction, or Three-Dimensional (3D) scanning, and has uses that span many disciplines. A projector, camera and Personal Computer (PC) are required to perform such 3D scans. Slight variances in synchronization between these three devices can cause malfunctions in the process due to the limitations of PC graphics processors as real-time systems. Previous work used a Field Programmable Gate Array (FPGA) to both drive the projector and trigger the camera, eliminating these timing issues, but still needing an external camera. This thesis proposes the incorporation of the camera with the FPGA SLI …

Stability Analysis And Design Of A Tracking Filter For Variable Frequency Applications, Pranav Aramane

Theses and Dissertations--Electrical and Computer Engineering

The work presented in this thesis is a frequency adaptive tracking filter that can be used in exact tracking of power frequencies and rejection of unwanted harmonics introduced during power disturbances. The power synchronization process includes power converters and other equipment that have many non-linear components that introduce unwanted harmonics. This new design is motivated by the requirement of a filter that can filter all the harmonics and exactly track a rapidly varying fundamental frequency with little time delay and phase error. This thesis analyzes the proposed filter mathematically based on Lyapunov theory and simulations are presented to show the …

Fabrication And Characterization Of Organic-Inorganic Hybrid Perovskite Solar Cells, Hojjatollah Sarvari

Theses and Dissertations--Electrical and Computer Engineering

Solar energy as the most abundant source of energy is clean, non-pollutant, and completely renewable, which provides energy security, independence, and reliability. Organic-inorganic hybrid perovskite solar cells (PSCs) revolutionized the photovoltaics field not only by showing high efficiency of above 22% in just a few years but also by providing cheap and facile fabrication methods.

In this dissertation, fabrication of PSCs in both ambient air conditions and environmentally controlled N₂-filled glove-box are studied. Several characterization methods such as SEM, XRD, EDS, Profilometry, four-point probe measurement, EQE, and current-voltage measurements were employed to examine the quality of thin films …

Advanced Synchronous Machine Modeling, Yuqi Zhang

Theses and Dissertations--Electrical and Computer Engineering

The synchronous machine is one of the critical components of electric power systems. Modeling of synchronous machines is essential for power systems analyses. Electric machines are often interfaced with power electronic components. This work presents an advanced synchronous machine modeling, which emphasis on the modeling and simulation of systems that contain a mixture of synchronous machines and power electronic components. Such systems can be found in electric drive systems, dc power systems, renewable energy, and conventional synchronous machine excitation. Numerous models and formulations have been used to study synchronous machines in different applications. Herein, a unified derivation of the various …

Design And Implementation Of A Micro-Inverter For Photovoltaic Applications, Chi-Thang Phan-Tan

Masters

The objective of this work is to design and build a novel topology of a micro-inverter to directly convert DC power from a photovoltaic module to AC power. In the proposed micro-inverter, a structure with two power stages, which are DC/DC and then DC/AC converters, is used. A novel MPPT algorithm is implemented and evaluated in the DC/DC converter to optimize the solar panel energy production. The new method operates with an efficiency of 97.9%, which is a 1% improvement on the standard method, and a response time of

In this research, the following approach is taken. A literature review …

Controlled Switching Of Reactive Loads And Commisioning Regimes, Eoin Cowhey

Masters

Switching is a vital task in any power system for ensuring its safe and reliable operation. Switching may be necessary for fault clearance, to ensure wider system stability and to prevent damage to plant. It is essential for isolation, to allow technicians to carry out maintenance tasks safely. Also, switching of reactive loads such as shunt capacitor banks and shunt reactors, is crucial for controlling system voltage.

Switching of some loads however, may produce voltage transients and heavy transient inrush currents which can impact on wider system power quality, impact customers and cause damage or deterioration of the insulation of …