Electrical and Electronics Commons^™

Modeling Leakage Currents In Metal Insulator Metal Structures With High K Materials, Priyamvada Maleeswaran

Electrical & Computer Engineering Theses & Dissertations

Various products such as personal computers, cellular phones and mobile devices require high speed and low power consumption. Such improvements have been attained by minimizing physical dimensions of electronic devices, leading to high density integration of transistors and capacitors on integrated chips (]Cs). However, as a consequence of down-scaling device dimensions, tunneling of electrons through thin gate oxides (SiO₂) increases, leading to increased static power leakage. This constitutes wastage in power, and for the case of memory applications necessitates faster refresh cycles. In order to overcome such issues, high-k materials (such as HfO₂ and ZrO₂) …

Analysis Of Compensation Techniques Applied To The Control Of Converter Connected Synchronous Wind Turbines And Dfig’S During Grid Disturbances., Joseph Kearney, Michael Conlon, Eugene Coyle

Conference papers

This paper investigates control schemes to improve the performance of converter connected synchronous generators and DFIG’s to grid voltage unbalance and grid faults. Both the synchronous generator with a full converter and a DFIG are modelled in Matlab/Simulink. The control schemes of both turbines are modified to improve their performance during grid disturbances including grid voltage unbalance and single-phase faults. These disturbances are introduced into the models at specific times to analyse the performance of the wind generation systems. The performances of both systems to the grid disturbances are compared and the results are analysed.

The Unprecedented Assimilation Of Mobile Telephony In Ireland: A Phenomenon Of The Celtic Tiger Era Or A Result Of Cultural Traits?, Andreas Scheibelhut

Masters

Following the universal acceptance of mobile telephony the once elitist gadget has become an indispensable democratic tool of everyday communications over the last three decades. Controversially, this thesis illustrates that its level of both adoption and usage did not develop in a similar homogenous pattern in selected OECD countries. In particular, the Irish performance is rather astonishing given the speed of adoption as well as the exceptional high revenue figures achieved by the wireless operators. Consequently, this work determines a selection of factors that drive and encourage both the adoption and usage of cellular telephony in Ireland. The Irish experience …

Blind Recognition Of Analog Modulation Schemes For Software Defined Radio, Haifeng Xiao

Dissertations

With the emergence of software defined radios (SDRs), an adaptive receiver is needed that can configure various parameters, such as carrier frequency, bandwidth, symbol timing, and signal to noise ratio (SNR), and automatically identify modulation schemes. In this dissertation research, several fundamental SDR tasks for analog modulations are investigated, since analog radios are often used by civil government agencies and some unconventional military forces. Hence, the detection and recognition of "old technology" analog modulations remain an important task both for civil and military electronic support systems and for notional cognitive radios.

In this dissertation, a Cyclostationarity-Based Decision Tree classifier is …

Graphene-Coated Substrates For Biochemical And Optoelectronic Applications, Amrita Banerjee

Dissertations

Graphene - monolayer or a few layers of graphite -- has proven to possess remarkable properties: large thermal conductivity, mechanical robustness, two-dimensional ultra large electronic mobility, chemical inertness and biochemical compatibility. Realization of some applications has been impeded by lack of a large area deposition method. By using a novel methodology to deposit graphene on solid and perforated substrates, various optoelectronic and biochemical elements have been demonstrated in this thesis: (1) graphene based transistors were fabricated and their characteristics were assessed. The mobility for such transistors exceeded 5000 cm2/V·s, much larger than their silicon based counterparts. Such attribute opens up …

High Aspect Ratio Electrodes For High Yield Electroporation Of Cells, Anil B. Shrirao

Dissertations

Electroporation is a widely used process in cell biology studies. It uses an electric field to create pores on the cell membrane in order to either insert exogenous molecules inside the cells or disrupt the cell membrane to kill the cells. Current micro-fluidic electroporation devices use the planar electrodes situated at the bottom of a microchannel. These planar electrodes i) require a high voltage and ii) generate a nonuniform electric field which result in low yield of the electroporation. The standard silicon microfabrication technologies are not suitable to fabricate non-planar electrodes required to increase the yield of electroporation.

In this …

Gpu Implementation Of Block Transforms, Boyan Zhang

Theses

Traditionally, intensive floating-point computational ability of Graphics Processing Units (GPUs) has been mainly limited for rendering and visualization application by architecture and programming model. However, with increasing programmability and architecture progress, GPUs inherent massively parallel computational ability have become an essential part of today's mainstream general purpose (non-graphical) high performance computing system. It has been widely reported that adapted GPU-based algorithms outperform significantly their CPU counterpart.

The focus of the thesis is to utilize NVIDIA CUDA GPUs to implement orthogonal transforms such as signal dependent Karhunen-Loeve Transform and signal independent Discrete Cosine Transform. GPU architecture and programming model are examined. …

Modeling Of Power Semiconductor Devices, Tanya Kirilova Gachovska

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

One of the requirements for choosing a proper power electronic device for a converter is that it must possess a low specific on-resistance. The specific on-resistance of a bipolar device is related to the base width and doping concentration of the lightly doped drift region. This means that the doping concentration and the width of the low-doped base region in a bipolar device must be carefully considered to achieve a desired avalanche breakdown voltage and on-resistance. In order to determine the technological parameters of a semiconductor device, a one dimensional analysis is used to calculate the minimum depletion layer width, …

Technology Portal For Energy Efficient Buildings, Larry D. Hermanson, Daniel Studer, Annie Mroz

STAR Program Research Presentations

Project: Technology Portal for Energy Efficient Buildings

Date: August 2, 2012

Author: Larry Hermanson

Mentor: Daniel Studer

Cohort: Annie Mroz

Lab site: National Renewable Energy Laboratory (NREL)

Buildings account for 71% of the electricity demand and 39% of the primary energy consumption in the United States. The Commercial Buildings Group at NREL provides builders, designers and building owners accurate information to significantly improve the energy efficiency of new and existing buildings. The Technology Portal for Energy Efficient Buildings will increase the accessibility of standardized and credible energy performance data for all building systems, thereby allowing building owners to better evaluate …

3.5 To 30 Mhz Automatic Antenna Impedance Matching System, William Blodgett

Electrical Engineering

Two-way communications using 3 to 30 MHz, high-frequency (HF) radio, also known as shortwave radio, provides worldwide coverage with no infrastructure required between stations. Amateur or “Ham” radio operators apply this advantage to long distance communications and to provide disaster relief communications. Optimum frequencies for long distance propagation are time-of-day variant necessitating an operating frequency range of 3 to 30 MHz. HF half wave dipole antenna length varies from 15 to 150 ft over this range. Fixed-length antenna impedance varies with frequency due to physical dimension dependent capacitance and inductance. Maximum transmitter to antenna power transfer occurs when the transmission …

Spectral Analysis Of Encrypted Chaotic Signals Using Fast Fourier Transforms And Laboratory Spectral Analyzers, Monish Ranjan Chatterjee, Abhinay Kundur

Electrical and Computer Engineering Faculty Publications

The use of acousto-optic chaos, as manifested via first-order feedback in an acousto-optic Bragg cell, in encrypting a message wave and subsequently recovering the message in the receiver using a chaotic heterodyne strategy, has been reported recently [1-3]. In examining the dynamical system analytically using computer simulation, (expected) modulated chaos waveforms are obtained within specified observation windows.

Because of the relatively random nature inherent in chaos waveforms, it is essentially impossible to ascertain from the visual display of the chaotic wave whether a given message signal has in fact modulated the chaotic "carrier". In fact, it has been observed from …

Ultra-Low Voltage Digital Circuits And Extreme Temperature Electronics Design, Aaron J. Arthurs

Graduate Theses and Dissertations

Certain applications require digital electronics to operate under extreme conditions e.g., large swings in ambient temperature, very low supply voltage, high radiation. Such applications include sensor networks, wearable electronics, unmanned aerial vehicles, spacecraft, and energyharvesting systems. This dissertation splits into two projects that study digital electronics supplied by ultra-low voltages and build an electronic system for extreme temperatures. The first project introduces techniques that improve circuit reliability at deep subthreshold voltages as well as determine the minimum required supply voltage. These techniques address digital electronic design at several levels: the physical process, gate design, and system architecture. This dissertation analyzes …

Delay Insensitive Ternary Logic Utilizing Cmos And Cntfet, Ravi Sankar Parameswaran Nair

Graduate Theses and Dissertations

As digital circuit design continues to evolve due to progress of semiconductor processes well into the sub 100nm range, clocked architectures face limitations in a number of cases where clockless asynchronous architectures require substantially less power, generate less noise, and produce less electromagnetic interference (EMI). This dissertation develops the Delay Insensitive Ternary Logic (DITL) asynchronous design paradigm that combines the designs aspects of similar Dual-Rail asynchronous paradigms and Boolean logic to create a single wire per bit, three voltage signaling and logic scheme.

DITL is designed at the transistor level using multi-threshold CMOS and carbon nanotube (CNT) FETs to develop …

Analysis Of Fiber Bragg Gratings For Ultrasonic Detection, Tongqing Liu

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

Fiber optic sensors became an emerging technique to detect ultrasonic emissions in the last decade. Their light weight, immunity to electromagnetic interference and capacity of being multiplexed make them defeat their electronic counterparts in various applications. In this thesis we presented a novel fiber optic ultrasonic sensor based on pi phase shift fiber Bragg gratings. Numerical simulations were performed to study the characteristics of pi phase shift fiber Bragg gratings impinged by ultrasonic waves. The coupling theory was introduced to analyze the change of fiber Bragg gratings when impinged by ultrasonic waves, and the transfer matrix method was utilized to …

Highly Sensitive X-Ray Detectors In The Low-Energy Range On N-Type 4h-Sic Epitaxial Layers, K. C. Mandal, P. G. Muzykov, J. R. Terry

Faculty Publications

No abstract provided.

Nanoscale Contacts Between Semiconducting Nanowires And Metallic Graphenes, Seongmin Kim, David B. Janes, Sung-Yool Choi, Sanghyun Ju

Birck and NCN Publications

Metal–semiconductor (M–S) junctions are important components in many semiconductor devices, and there is growing interest in realizing high quality M–S contacts that are optically transparent. In this paper, we present our investigations into the characteristics of M–S junction in a semiconducting ZnO nanowire that was directly grown on a multilayer graphene film (MGF). The synthesized nanowires were fabricated into two-terminal devices with MGF as one contact and Al as the other contact. By comparison with devices employing Al contacts at both ends, the nanowire resistivity and specific contact resistivity of the MGF–nanowire contact can be extracted. The extracted specific contact …

Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun

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

Micro-electronic industry has been boosting the capability of wireless mobile devices on full-scale. However, battery, as the only power source of most mobile devices, is experiencing a relatively slow development. Therefore, how to optimally utilize the limited battery energy on mobile devices under a predefined performance requirement becomes a critical issue. On the other hand, it is still unclear that how the battery capacity consumption is allocated on different working pattern of a specific video codec under various tempo-spatial scales and parameters, which has posed a design challenge on power management on multimedia communication system. Furthermore, an optimization method is …

Solar Light Bulb, David G. Guzman, Virgilio Gonzalez

COURI Symposium Abstracts, Summer 2012

The Solar Lighting project is a work driven towards building a low-cost and environmental-friendly solar bulb and to understanding the science behind its behavior. A solar light bulb refers to a device capable of absorbing and transferring solar energy to light up an enclosed area. By using the physical properties of fluids and light is possible to manipulate solar light waves to illuminate an enclosed structure. Moreover, this project attempts to utilize recycled materials that reduce the cost of such device, helping not only the planet but also the costumer’s pocket. The ultimate goal for this project is to scientifically …

Low Power Sigma Delta Converter, Noel P. Martinez, Praveen K. Palakurthi, Eric Macdonald

COURI Symposium Abstracts, Summer 2012

Sub threshold technology allows for circuits to run at their best efficiency with the lowest amount of energy possible. The aim of this research was to combine this technology along with radiation hardness, or the ability for circuits to resist radiation without getting corrupted data. A chip that can convert digital data into analog data (DAC) was created and programmed using verilog, a Hardware Description Language (HDL). With verilog, we created digital data that would eventually be fed into the chip using a field-programmable gate array (FPGA) board. We tested our digital data using a test bench on the computer …

Dynamics Of Non-Thermal Plasma Jets Under Variable Pressure, Mehmet Arda Akman

Electrical & Computer Engineering Theses & Dissertations

Non-thermal plasma (NTP) jets driven by short DC pulses have attracted the attention of researchers within the past decade due to their promising bio-medical applications in the fields of wound healing, cancer treatment and sterilization. The ability to operate at atmospheric pressure, room temperature and simple device configuration has greatly contributed to their appeal and adoption in the plasma science community. However, the mechanisms that sustain the plasma generation and propagation in ambient air are currently a topic of debate. For instance, what appears as a continuous stream of a plasma plume extending outwards from a plasma device into the …

The Double Pendulum: Construction And Exploration, Benjamin J. Knudson

Physics

The exploration of a nonlinear mechanical system, the Double Pendulum, a physical pendulum on the end of a physical pendulum, using analytic and experimental approaches. Also included discussion of the design and construction of the Double Pendulum apparatus to work with Vernier LabPro and LoggerPro. The apparatus outputs live data of the angles to a LoggerPro which collects and produces time evolution graphs as well as a corresponding animation lending itself to comparison with theoretical models. Normal mode frequencies are found both analytically and experimentally for the the general (real) double pendulum. Examples of both simple (periodic) and complex (chaotic) …

Diagnosis Of Breast Cancer By Optical Image Analysis, Salim J. Attia, Jonathan Blackledge, Ziad M. Abood, I. R. Agool

Conference papers

We consider the process of object detection, recognition and classification in digital optical images of human breast cells with the aim of differentiating between normal and abnormal (cancerous) cells. The work is based on research into the development of a breast cancer screening system that can be used by cytologists to differentiate between benign and malignant types using images that are typical of those currently interpreted by cytologists world-wide. The approach considered is based on feature vectors which are of two types. We consider statistical features such as the mode, median, mean, and standard deviation and features composed of Euclidian …

A Wireless And Digital Electrode Bus Topology For Biopotential Measurement, Mark Nolan, Edward Burke, Eugene Coyle

Conference Papers

The conventional biopotential measurement configuration utilises long lead wires which connect measuring electrodes to signal conditioning circuitry. The majority of bioelectric signals that are measured from the human body have a tiny signal amplitude (5µV-5mV range) and thus any interference that is induced on the lead wires can have a detrimental effect on the original signal. In this paper, we present an alternative configuration, in which digitisation occurs on the electrode, potentially providing enhanced signal measurement as well as significant benefits in terms of the simplification of the physical interconnections between electrodes. Multiple electrodes are combined to form a digital …

Fabrication And Characterization Of Torsional Micro-Hinge Structures, Mike Madrid Marrujo

Master's Theses

ABSTRACT

Fabrication and Characterization of Torsional Micro-Hinge Structures

Mike Marrujo

There are many electronic devices that operate on the micrometer-scale such as Digital Micro-Mirror Devices (DMD). Micro actuators are a common type of DMD that employ a diaphragm supported by torsional hinges, which deform during actuation and are critical for the devices to have high stability and reliability. The stress developed within the hinge during actuation controls how the actuator will respond to the actuating force. Electrostatically driven micro actuators observe to have a fully recoverable non-linear viscoelastic response. The device consists of a micro-hinge which is suspended by two …

A Study Of Integrated Uwb Antennas Optimised For Time Domain Performance, Antoine Dumoulin

Doctoral

Antennas for impulse radio ultra-wideband based portable devices are required to be compact and able to transmit or receive waveforms with minimal distortion in order to support proximity ranging with a centimetre-scale precision. The first part of thesis characterises several pulse types for use in the generation of picosecond-scale signals in respect to the regulatory power and frequency standards while the principles of antenna transient transmission and reception are stated. The proximity effect of planar conductors on the performance of an ultra-wideband antenna is investigated in both spectral and temporal domain demonstrating the relationship between the antenna-reflector separation and the …

Design And Simulation Of Interconnected H-Bridge Inverter, Samuel Muehleck

Computer Engineering

In this project, the research, design and simulation of an interconnected H-bridge single-phase inverter was explored. The inverter design was divided into three separate sections. First, a VHDL programmed CPLD was used to generate control signals for the transistors of the inverter circuit. Second, power electronics was used to create an inverter circuit to change a DC input to a 60 Hz AC output. Lastly, additional circuits were used to link the generated control signals to the MOSFET transistors of the inverter circuit. The operation of the three components was then validated with computer simulations. Results of computer simulation demonstrate …

Design, Construction, And Evaluation Of An Automated Chicken Coop Door, Kyle Inks

BioResource and Agricultural Engineering

This senior project takes a look into the design, construction, and evaluation of an automated chicken coop door. The idea and need for such a door came from my mother Jan Inks. The parameters for the project include, low production cost, easy installation on existing coops, sleek design, automatically open at a set time in the morning, and automatically close at a set time in the evening.

Energy Harvesting From Elliptical Machines: Dc-Dc Converter Design Using Sepic Topology, Martin Kou

Master's Theses

Cal Poly’s ongoing Energy Harvesting from Exercise Machines (EHFEM) project is a very convenient and cost-effective way for generating DC power from physical exercise and sending it back to the electrical grid as AC power, providing a renewable energy source for the future. The EHFEM project consists of numerous subprojects involving converting different types of exercise machines for power generation. This project is a continuation of one of the previous subprojects, specifically involving an elliptical machine, and focuses on improving system functionality at different machine settings without altering the elliptical user’s experience by selecting a new DC-DC converter design, while …

Surveying First-Year Students Prior Conceptual Understanding Of Direct Current Resistive Electric Circuits: An Update, Aidan O'Dwyer

Conference papers

There is an increasing diversity of educational background of students entering Level 7 and Level 8 programmes in engineering in Irish third level education. Student reasoning about basic electricity concepts often differs from accepted explanations. The paper reports, analyses and reflects on the results of a multiple-choice diagnostic test to assess student understanding of such concepts (developed by Engelhardt and Beichner (2004) for U.S. high school and college students) taken by four cohorts of students, on the same DIT Level 7 engineering programme, from 2008-12 (n=106) and two cohorts of students, on the same DIT Level 8 engineering programme, from …

Cell Phone Charger For The Dc House Project, Andrew Hefner, Antonio Magdaleno

Electrical Engineering

The goal of this project is to create a multiple output cell phone charger for the DC House project. The cell phone charger is essentially a DC-DC converter. The converter takes an input of 48 volts from the outlet in the DC House and decreases the voltage level to 5 volts; the input voltage level of all cellular devices. By designing an isolated flyback converter with initial specification in LTSpice simulation software, a converter was created. By monitoring the input and output voltage and current using the multi-meters and electronic load, we determined the charger to be 71% efficient when …