Digital Commons Network^™

Deconvolution And Segmentation Of Ground Penetrating Radar Images, Vincent Krause

Masters Theses

Ground Penetrating Radar is a valuable tool for infrastructure condition evaluation as well as in archaeology and geology. The image produced by a GPR scan can be difficult to interpret due to the weak reflection amplitude, the overlap of reflections, and due to outside interference. This thesis proposes an algorithm to automate GPR scan interpretation. This will enable maintenance engineers to read GPR scans quickly and accurately.

The proposed algorithm framework uses an optimization-based deconvolution technique followed by a segmentation process. Each column of the image is deconvoluted and thus reducing them to a list of ordered pairs of reflection …

Modbus Implementation Using A Serial Link, Naresh Karnam

Masters Theses

Serial Communication is a process of sending one bit at a time, sequentially over a communication channel or a computer bus. RS-232 and RS- 484 are two such examples of the architecture of Serial Communication. This work primarily aims at establishing a communication channel between three entities namely the Controller also called the Console, the Relay Unit and a PC. This work aims at designing the communication model, using the Client-Server architecture and using the MODBUS protocol, as the standard for transmitting the bits in a Remote Terminal Unit (RTU) mode and for framing the characters. The MODBUS protocol also …

A Longest-Queue-First Signal Scheduling Algorithm With Quality Of Service Provisioning For An Isolated Intersection, Richard James Wunderlich

Masters Theses

In today's fast-paced society, the need to travel using automobiles is increasingly important. Aside from the road itself, the intersection is the most basic unit of a traffic system. As such, controlling the flow of traffic through intersections in an efficient manner has become a task of the utmost importance. The signal-scheduling algorithm described in this thesis is designed for just such a task. Concepts are drawn from the field of packet switching in computer networks and are applied to the traffic control problem. The method proposed utilizes a maximal weight matching algorithm to minimize the queue sizes at each …

The Detection Of Stress Corrosion Cracking In Natural Gas Pipelines Using Electromagnetic Acoustic Transducers, Austin P. Albright

Masters Theses

This thesis describes the refinement of a non-destructive, in-line inspection system sensor for the detection of stress corrosion cracks (SCCs) in natural gas pipelines. The sensors are prototype electromagnetic acoustic transducers (EMATs) for noncontact ultrasonic inspection. The focus areas discussed involve the statistically validated performance improvements achieved through the addition of 12 more features, the addition of Principal Component Analysis plus Linear Discriminant Analysis (PCA+LDA) to the classification algorithm, and most significantly the creating of a training set. The training set allowed PCA+LDA to be included in the classification algorithm, as well as allowing one set of no-flaw signature features, …

Impedance Matching And PspiceR Simulation Of One Atmosphere Uniform Glow Discharge Plasma (Oaugdp™) Reactor/Actuator Systems, Zhiyu Chen

Masters Theses

This thesis addresses two important issues relevant to One Atmosphere Uniform Glow Discharge Plasma (OAUGDP™) reactors and actuators ¾ impedance matching and PSpice^R simulation.

An OAUGDP™ reactor/actuator with the plasma energized can be modeled as a capacitor in parallel with a resistor. In addition, the non-ideality of the transformer between the RF power supply and the plasma reactor/actuator introduces an imaginary component in its impedance. Thus, the load of the RF power supply, as seen by its output terminals, is highly reactive. An impedance mismatch resulting from the absence of a matching network will cause a large reflected power …

Evaluation Of Losses In Hid Electronic Ballast Using Silicon Carbide Mosfets, Lakshmi Reddy Gopi Reddy

Masters Theses

HID lamps are used in applications where high luminous intensity is desired. They are used in a wide range of applications from gymnasiums to movie theatres, from parking lots to indoor aquaria, from vehicle headlights to indoor gardening. They require ballasts during start-up and also during operation to regulate the voltage and current levels. Electronic ballasts have advantages of less weight, smooth operation, and less noisy over electromagnetic ballasts. A number of topologies are available for the electronic ballast where control of power electronic devices is exploited to achieve the performance of a ballast for lighting. A typical electronic ballast …

Universal Voltage Rate Sensor Interface, Jayanth Chakradhar Kruttiventi

Masters Theses

Measurement of heat flux is required in many aerospace and heat treatment applications. Temperature data collected at embedded sites are noisy especially when measurements are taken in hostile environments. The predicted heat flux, when based on the rate of change of temperature, is more accurate than using temperature data as the latter data form is ill-posed. In the context of heat flux prediction, calculating the rate of change of temperature involves differentiation, which is the primary source of ill-posed effects.

This work involves developing a universal voltage rate sensor interface that minimizes these effects and also improves the signal-to-noise ratio. …

Fpga-Based Image Analysis System For Cotton Classing, Muhammad Imran Sharafat

Masters Theses

The design and implementation of an FPGA (field-programmable gate array) based image analysis system was undertaken to replace an older system whose components have become obsolete. Video from an analog camera is digitized by a video decoder. The data from the video decoder is stored in memory and then processed using an FPGA. The results are then transmitted over a universal serial bus (USB) to a host personal computer for additional processing. The system also controls the timing of a flash to correctly capture the images; it measures color and reflectance and is used to classify the quality of raw …

A 64-Channel Mixed-Signal Data Acquisition System For A Solid-State High Efficiency Neutron Detector Array, Anthony Gene Antonacci

Masters Theses

This thesis presents the design of multiple analog and digital blocks required to implement a desired solid-state data acquisition system for the High Efficiency Neutron Detector Array (HENDA) project under the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). This system encloses and is an extension of prior work described in [1] and [2]. The first prototype chip, named Patara, contained a charge sensitive front-end amplifier [2], and a semi-Gaussian shaper with baseline restore circuitry [1]. Patara III, described in this thesis, involved the addition of the following system components; two comparators, a selectable synchronous/asynchronous digital …

Analysis And Characterization Of A Sige Bicmos Low Power Operational Amplifier, Archana Yarlagadda

Masters Theses

Integrated circuit design for space applications can require radiation immunity, cryogenic operation and low power consumption. This thesis provides analysis and characterization of a SiGe BiCMOS low power operational amplifier (op amp) designed for lunar surface applications. The op amp has been fabricated on a commercially available 0.35-micron Silicon-Germanium (SiGe) BiCMOS process. The Heterojunction bipolar transistors (HBT) available in the SiGe process have been used in this op amp to take advantage of the total ionizing dose (TID) irradiation immunity and superb cryogenic operation, along with PMOS devices that show better TID immunity than their NMOS counterparts. The key features …

A Standard Cmos Compatible Bandgap Voltage Reference With Post-Process Digitally Tunable Temperature Coefficient, Sam D. Caylor

Masters Theses

An essential element of most robust analog/mixed-signal systems is a stable and precise bandgap voltage reference (BGR). CMOS compatible BGR circuits are generally limited by variability in output drift over temperature due to process variations. In this work a CMOS BGR is developed that provides simple, digitally-controlled post-process (i.e., post fabrication) trimming. The trimming is achieved through MOSFET switches used to adjust a current gain factor for the thermal voltage referenced current within the BGR circuit. This current is proportional to absolute temperature (PTAT). The PTAT current is injected into a series connected resistor and diode to ultimately provide an …

Fabrication And A Study On The Wetting Properties Of Nanostructured Surfaces, Meenaa Kalyanaraman

Masters Theses

Fluid behavior at the microscale exhibits large surface to volume ratios increasing the significance of interfacial phenomena. We have studied two microfluidic phenomena that utilize interplay between microstructure and chemical composition. The first one causes liquid droplets to roll off from surfaces with a very high contact angle. This phenomenon is called superhydrophobic behavior, can be controlled by several tuning parameters. The second one changes the wettability of liquids on a dielectric coated surface with electric potential. The experimental studies were done by first fabricating an ordered array of glass nanocones. Fiber drawing and differential glass etching processes were used …

Analysis, Modeling And Testing Of A Multi-Receiver Wireless System For Telemetry Applications, Thomas Ebel

Masters Theses

This thesis investigates the potential value of multiple co-located receiver units for telemetry applications. In this thesis, a test board based on the NRF24L01 RF chip produced by Nordic Semiconductor was tested. Testing consisted of sending pseudo-random test data over a link between two test boards at progressive distances. Packet loss rate was identified as the dominant failure mode of the chip, and was used to determine performance increase. A parametric model of the chip performance was developed based on coherent and noncoherent FSK detectors and curve fit to the experimental data to model the performance of a single GFSK …

Fabrication Of Nano-Injection Needles For Neural Pathway Study In Mice, Sangeetha Swaminathan

Masters Theses

The potential of micro-needles to provide an interconnection between the microscopic and the macroscopic worlds makes it one of the most revolutionary fields in health care, allowing for precise transdermal drug delivery of highly targeted small doses of the active compound. Current micro electro mechanical systems (MEMS) technologies, originally designed for the micro-electronics industry, have been utilized in the fabrication of different micro-needle designs and their integration with various micro-fabricated micro-fluidics devices. The target of this thesis is to achieve a micro-needle injection system to deliver several strains of pico-liter volumes of a fluid combination of transgenic virus and luminescent …

A Full Scale Camera Calibration Technique With Automatic Model Selection – Extension And Validation, Vitaliy Leonidovich Orekhov

Masters Theses

This thesis presents work on the testing and development of a complete camera calibration approach which can be applied to a wide range of cameras equipped with normal, wide-angle, fish-eye, or telephoto lenses. The full scale calibration approach estimates all of the intrinsic and extrinsic parameters. The calibration procedure is simple and does not require prior knowledge of any parameters. The method uses a simple planar calibration pattern. Closed-form estimates for the intrinsic and extrinsic parameters are computed followed by nonlinear optimization. Polynomial functions are used to describe the lens projection instead of the commonly used radial model. Statistical information …

Predictive Models Of An Electro-Mechanical Driving System For Failure Testing Of Strain Gauges, Brent Ellis

Masters Theses

Strain gauges are bonded at high stress locations on the surface of critical structural components such as turbine blades to measure fatigue characteristics and detect early warning signs of high cycle fatigue. However, strain gauges do not always report expected measurements. The usual response by maintenance technicians to these failing signals is to investigate the component for weakness, check the placement of the gauges on the component, or examine the instrumentation for failure or damage. However, little research has been conducted to show when the failing signals are the fault of the strain gauge. Such failure modes of strain gauges …

Model Reduction Techniques For Fluid Dynamical Flow Based Pde Control Problems, Jason Harold Foster

Masters Theses

This thesis deals with the practical and theoretical implications of model reduction for aerodynamical flow based control problems. Various aspects of model reduction are discussed that apply to Partial Differential Equation (PDE) based models in general. Specifically, the Proper Orthogonal Decomposition (POD) of a high dimension system is discussed as well as frequency domain identification methods are discussed for initial model creation. Projections on the POD basis give a Galerkin model. Then, the methods of balanced truncation and Hankel optimal norm reduction are applied to the Galerkin model. A state space model is formed by a Galerkin projection of the …

Hardware Accelerated Scalable Parallel Random Number Generation, Junkyu Lee

Masters Theses

The Scalable Parallel Random Number Generators library (SPRNG) is widely used due to its speed, quality, and scalability. Monte Carlo (MC) simulations often employ SPRNG to generate large quantities of random numbers. Thanks to fast Field-Programmable Gate Array (FPGA) technology development, this thesis presents Hardware Accelerated SPRNG (HASPRNG) for the Virtex-II Pro XC2VP30 FPGAs. HASPRNG includes the full set of SPRNG generators and provides programming interfaces which hide detailed internal behavior from users. HASPRNG produces identical results with SPRNG, and it is verified with over 1 million consecutive random numbers for each type of generator. The programming interface allows a …

The Reliability Of Signal Strength For Localization Of High-Density Zigbee Wireless Networks, Brandon Jeremy Rogers

Masters Theses

This thesis investigates the reliability of ZigBee signal strength within a high-density wireless network, specifically looking at the Link Quality Indicator (LQI) as provided by the physical layer and accessible at the networking and application layers within the stack protocol. It also investigates methods by which LQI can be used for discovery, identification, and localization of nodes within a ZigBee wireless network. The thesis concentrates on practical approaches specifically as it would pertain to commissioning a high-density network for an application such as lighting control in building automation. There are seven potential algorithms proposed using factors such as minimum distance …

Transceiver Design And Radio Frequency Integrated Circuits Evaluation Via Electronic Design Automation, Yu Ming Chen

Masters Theses

This thesis study presents the theory and design methodology of Radio Frequency Integrated Circuits (RFIC) and analyzes a RF frond-end receiver and down-conversion mixers using circuit evaluation tools. The theory of RF is described on both architectures and circuit levels with respect to monolithic implementation in integrated semiconductor technologies. The design methodology provides an efficient and practical way to approach ·the theoretical values by using an Electronic Design Automation (EDA) tool called Cadence Virtuoso custom design platform Based on the libraries provided by the Cadence Virtuoso, a Heterodyne receiver and two Gilbert mixer circuits have . been evaluated through the …

Design And Analysis Of A General Purpose Operational Amplifier For Extreme Temperature Operation, Chandradevi Ulaganathan

Masters Theses

Operational amplifiers (op amps) are key functional blocks that are used in a variety of analog subsystems such as switched-capacitor filters, analog-to-digital converters, digital-to-analog converters, voltage references and regulators, etc. There has been a growing interest in using such circuits for "extreme environment" electronics, in particular for electronics capable of operating down to deep-cryogenic temperatures for lunar and Martian surface explorations.

This thesis presents the design and analysis of a general purpose op amp suited for “extreme environment” applications, with a wide operating temperature range of 93 K to 398 K. The op amp has been implemented using a CMOS …

A Novel Power Supply For Generating A One Atmosphere Uniform Glow Discharge Plasma (Oaugdp®), Laurent Jose Calvez

Masters Theses

A high voltage transformer connected to an atmospheric plasma generator is driven as a current-fed push-pull parallel resonant system, switched by a resonant lamp controller integrated circuit from Texas Instruments (UC3872) in such a manner as to be automatically maintained at resonance. The frequency range of interest is the audio range, which creates a particularly uniform glow discharge in atmospheric pressure air. Frequency control is achieved by a specially constructed high voltage variable capacitor connected parallel to the secondary, in conjunction with a variable parallel primary inductance. Voltage control is achieved by variation of the input DC current amplitude.

A Crosslayer Routing Protocol (Xlrp) For Wireless Sensor Networks, Raghul Gunasekaran

Masters Theses

The advent of wireless sensor networks with emphasis on the information being routed, rather than routing information has redefined networking from that of conventional wireless networked systems. Demanding that need for contnt based routing techniques and development of low cost network modules, built to operate in large numbers in a networked fashion with limited resources and capabilities. The unique characteristics of wireless sensor networks have the applicability and effectiveness of conventional algorithms defined for wireless ad-hoc networks, leading to the design and development of protocols specific to wireless sensor network. Many network layer protocols have been proposed for wireless sensor …

Wimax Software Defined Radio, Assad Saleem

Masters Theses

As processors and configurable devices are getting faster and smaller, they are giving rise to better solutions for various communications systems and standards. In this paper, the implementation of a software defined radio for WiMAX is presented. This paper highlights the system model for simulation to achieve better understanding of the system, which was developed in MATLAB. Also, included in the paper is the discussion of the physical implementation of this communication system. The system is build around National Instruments’ PCI 5640 hardware which features a Xilinx Virtex-II FPGA. Naturally, LabVIEW was the tool used to implement the hardware/software co-design.

Dynamic Modeling And Simulations Of Solid Oxide Fuel Cells For Grid-Tied Applications, Nagasmitha Akkinapragada

Masters Theses

"As energy consumption rises, one must find suitable alternative means of generation to supplement conventional existing generation facilities. In this regard, distributed generation (DG) will continue to play a critical role in the energy supply-demand realm. The common technologies available as DG are micro-turbines, solar photovoltaic systems, fuel cells stack and wind energy systems. In this thesis, a dynamic model of solid oxide fuel cell (SOFC) is presented. Fuel cells operate at low voltages and hence need to be boosted and inverted in order to be connected to the utility grid. The interconnection of the SOFC with a DC-DC converter …

35-45 Giga Hertz Transceiver System For Phase And Magnitude Detection, Aman Aflaki Beni

Masters Theses

"Nondestructive evaluation (NDE) is the science and practice of examining an object in a way that the object's usefulness is not adversely affected. Different types of NDE methods exist but this thesis is based on microwave and millimeter wave NDE using imaging techniques. Microwave NDE is based on illuminating the object under test with a microwave signal and studying the various properties of the reflected signal from the object. This reflected signal contains some information about the inner structure of the object under test. This information may be contained in several parameters including the phase and magnitude of the reflected …

Current Measurement In Power Electronic And Motor Drive Applications - A Comprehensive Study, Asha Patel

Masters Theses

"Current measurement has many applications in power electronics and motor drives. Current measurement is used for control, protection, monitoring, and power management purposes. Parameters such as low cost, accuracy, high current measurement, isolation needs, broad frequency bandwidth, linearity and stability with temperature variations, high immunity to dv/dt, low realization effort, fast response time, and compatibility with integration process are required to ensure high performance of current sensors. Various current sensing techniques based on different physical effects such as Faraday's induction law, Ohm's law, Lorentz force law, magneto-resistance effect, and magnetic saturation are studied in this thesis. Review and examination of …

Microfluidic Biosensors For Intelligent Metabolite Monitoring, Nitin Radhakrishnan

Masters Theses

"Baseline (zero-value) drift and sensitivity degradation are two common problems related with biosensors. In order to overcome these problems, there is a great need for integrating an on-demand, in situ self-diagnosis and self-calibration unit along with the sensor. Utilizing the microfluidic technology, it is possible to explore the feasibility of implementing this function without any externally coupled bulky apparatus. A microsystem including a microfluidic channel and calibration electrodes are prepared by microfabrication techniques"--Abstract, page iv.

A Software Defined Radio For Research Into Cognitive Radio, Jason Michael Pratt

Masters Theses

Software defined radios are capable of transmitting and receiving signals over a broad range of frequencies, and can alter their carrier frequency, modulation scheme, and power level by changing the software controlling the radio. Because of these capabilities, a software defined radio is the necessary platform for research into cognitive radio. The aim of cognitive radio is to more fully utilize the RF spectrum by allowing wireless communication systems to scan the spectrum for unused frequency bands and dynamically establish communication over one of those unused bands. This thesis gives a brief introduction into cognitive radio, and currently existing software …

Detection Of Flash In Dermoscopy Skin Lesion Images, Radhika Nagane

Masters Theses

"Dermoscopy images of skin lesions are often acquired by covering the skin with mineral oil, alcohol, another liquid or a gel and illuminating the area at a low angle of incidence from all directions before taking the photograph. Deeper pigment patterns are more visible in this type of image than in a clinical image because the liquid immersion and structured light effectively make the upper layers of the skin more transparent. Flash regions are the small, high reflectance areas in the image where direct reflections of the illumination source(s) cause undesirable bright spots in the image. These flash regions may …