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Masters Theses

2008

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Articles 1 - 22 of 22

Full-Text Articles in Electrical and Computer Engineering

Multi-Channel Real-Time Communication In Wireless Sensor Network, Nitish Kumar Jha Dec 2008

Multi-Channel Real-Time Communication In Wireless Sensor Network, Nitish Kumar Jha

Masters Theses

Many radio chips used in today's sensor mote hardware can work at different frequencies. Recently, several multi-channel communication protocols have been proposed to improve network throughput and reduce packet loss for wireless sensor networks. However, existing work does not provide explicit guarantees for application-specified end-to-end communication delays, which are critical to many real-time applications such as surveillance and disaster response. On the other hand, those radio chips also have adaptable transmission power which allows a trade-off between communication delays and energy efficiency.

This work proposes two multi-channel real-time communication protocols. One of the protocols features a node-based channel assignment policy …


Design And Development Of An Apd Algorithm Development Board For Positron Emission Tomography, Rakesh Mallem Dec 2008

Design And Development Of An Apd Algorithm Development Board For Positron Emission Tomography, Rakesh Mallem

Masters Theses

Using the PET scanner, three dimensional images of the human body with sufficient detail can be viewed which help physicians to visualize both normal metabolic functions and discover the chemical processes underlying physical abnormalities. Commercial PET scanners employ Photo Multiplier Tubes to detect the anti-matter annihilation photons and amplify the signals to a suitable level for digital sampling. Photomultiplier tubes provide extremely high sensitivity and exceptionally low noise compared to other photosensitive devices currently used to detect radiant energy in the ultraviolet, visible and near infrared regions. A combined magnetic resonance positron emission tomography (MR-PET) modality would require a solid-state …


Wide-Area Surveillance System Using A Uav Helicopter Interceptor And Sensor Placement Planning Techniques, Marcus James Jackson Jul 2008

Wide-Area Surveillance System Using A Uav Helicopter Interceptor And Sensor Placement Planning Techniques, Marcus James Jackson

Masters Theses

This project proposes and describes the implementation of a wide-area surveillance system comprised of a sensor/interceptor placement planning and an interceptor unmanned aerial vehicle (UAV) helicopter. Given the 2-D layout of an area, the planning system optimally places perimeter cameras based on maximum coverage and minimal cost. Part of this planning system includes the MATLAB implementation of Erdem and Sclaroff’s Radial Sweep algorithm for visibility polygon generation. Additionally, 2-D camera modeling is proposed for both fixed and PTZ cases. Finally, the interceptor is also placed to minimize shortest-path flight time to any point on the perimeter during a detection event. …


Multichannel Time-Stamping-Based Correlator And Hardware Simulator For Photon Correlation Spectroscopy, Isaac P. Lescano Mendoza May 2008

Multichannel Time-Stamping-Based Correlator And Hardware Simulator For Photon Correlation Spectroscopy, Isaac P. Lescano Mendoza

Masters Theses

In fluorescence correlation spectroscopy and dynamic light scattering, digital correlators acquire the autocorrelation function of detected photons to measure diffusional dynamics of biomolecules and small particles. Multi-channel data from different wavelengths or scattering angles provide increased information for resolving multiple species. Similarly, in single-molecule spectroscopy and in experiments on photon entanglement, there is a need to acquire time stamps of photons from multiple detectors. To enable such advances, a cost-effective Multichannel Time-Correlator (MTC) and a Multichannel Hardware Simulator (MHS) were developed, each based on a reconfigurable digital input/output card, recently available from National Instruments. The field-programmable-gate-array (FPGA) cores of the …


Remote Monitoring Of Barowell Pumps Using A Radio Link, Paul R. Schwer May 2008

Remote Monitoring Of Barowell Pumps Using A Radio Link, Paul R. Schwer

Masters Theses

Barowell pumps are notorious for having problems and failures, which sometimes occur at the most inopportune times during aeropropulson testing. These failures could be better predicted with proper health monitoring. Continuous monitoring of changes in the health of the pump would allow timely preventive and corrective maintenance to be performed as necessary to reduce failures and reduce plant downtime.

This thesis addresses a wireless method to monitor these pumps remotely by a user located in the control room. The operator can note the ultrasonic amplitude of the bearings on the pumps and make a decision to schedule preventive maintenance.

An …


Temperature Characterization Of The Ultracapacitor Serial Resistance Using A Constant Voltage Source, Curtis W. Miller May 2008

Temperature Characterization Of The Ultracapacitor Serial Resistance Using A Constant Voltage Source, Curtis W. Miller

Masters Theses

This thesis examines the temperature effects on an ultracapacitor’s equivalent series resistance using a constant voltage source. Previous research has focused on developing models using constant current source. However, as the ultracapacitor technology develops, allowing for the expansion of these devices into new power applications, it is important to understand how ultracapacitors will perform in various temperatures and charging and discharging methods. By predicting the ultracapacitor behavior, systems can be optimized for efficiency and minimize internal circuit losses.

For this thesis, Matlab was used to plot the experimental data and to provide best fit curves with their respective coefficients to …


Development Of Gate-Controlled Dc Electrokinetic Micropumps, Prachya Mruetusatorn May 2008

Development Of Gate-Controlled Dc Electrokinetic Micropumps, Prachya Mruetusatorn

Masters Theses

Lab-on-chip (LOC) devices have received considerable attention in research and development for automated, high-throughput biological and chemical analysis. While much progress has been accomplished; however, fluid flow control still needs improvement and reminds one of the significant challenges for the future practical LOC devices. This thesis explores the application of electroosmosis (EO) technique and field effect flow control (FEFC) technology for micropumps, an important microfluidic component of LOC systems.

In this work, electroosmosis method was employed to electro-kinetically move the working fluid under a longitudinal electric field, and the FEFC technique was also utilized to manipulate the Electroosmotic Flow (EOF) …


A Low Power Integrated Circuit For Implantable Biosensor Incorporating An On-Chip Fsk Modulator, Taeho Oh May 2008

A Low Power Integrated Circuit For Implantable Biosensor Incorporating An On-Chip Fsk Modulator, Taeho Oh

Masters Theses

Medical care has been significantly improved in recent years due to tremendous technological advancement in the field of CMOS technology. Among those improvements, integrated circuit design and sensing techniques have brought to the doctors more flexibility and accuracy of examinations of their patients. For example, a diabetic patient needs to visit a hospital on a regular basis for the examination and proper treatment. However, with the tremendous advancement in electronic technology, a patient can soon monitor his or her own blood glucose level at home or at office with an implantable sensor which can also trigger insulin pump attached to …


Ac Electrokinetic Manipulation Of Microfluids And Particles Using Orthogonal Electrodes, Kai Yang May 2008

Ac Electrokinetic Manipulation Of Microfluids And Particles Using Orthogonal Electrodes, Kai Yang

Masters Theses

AC electrokinetics (ACEK) is a promising technique to manipulate micro/bio-fluids and particles. It has many advantages over DC electrokinetics for its low applied voltage, portability and compatibility for integration into lab-on-a-chip devices. This thesis focuses on the design of a multi-functional orthogonal microelectrode system that induces ACEK effect for manipulation of microfluids and particles. Orthogonal electrode configuration used in this research can achieve maximum non-uniform electric field distribution, resulting in strong fluid and particle motion. In the experiments, three types of microflow fields were observed by changing the applied electric signals. Three ACEK processes, capacitive electrode polarization, Faradaic polarization, and …


Design And Analysis Of A Delta Sigma Modulator For A Fractional N Phase Locked Loop Frequency Synthesizer Operating At 2.4 Ghz, Timothy R. Grundman May 2008

Design And Analysis Of A Delta Sigma Modulator For A Fractional N Phase Locked Loop Frequency Synthesizer Operating At 2.4 Ghz, Timothy R. Grundman

Masters Theses

With the advances in communications, frequency synthesizers are becoming essential for many different circuits and broadcast bands. This need led to the creation of the fractional N frequency synthesizer. This synthesizer has proven itself to be a great invention allowing for many improvements over similar concepts. However, it only reaches the full extents of its capabilities when it is combined with a Delta Sigma modulator. This combined circuit shows great advances in noise performance and frequency resolution.

The fractional N frequency synthesizer is merely an integer N PLL with the ability to change the division ratio. The first attempts to …


Improving Query Efficiency Of Multiresolution Data Aggregation For Analytical Exploration Of Large Relational Dataset, Yu-Ting Huang Apr 2008

Improving Query Efficiency Of Multiresolution Data Aggregation For Analytical Exploration Of Large Relational Dataset, Yu-Ting Huang

Masters Theses

Tree structures are developed to organize the data more efficiently by using fewer resources for searching records. This thesis investigates the tree's actual structure on the hard disk to see the influence of different kinds of structures on the tree building time and query execution time. In order to improve efficiency, one multi-file structure and two reorganization structures, BFS and DFS, are examined to achieve this goal. The results indicate that two reorganization structures on KDB-tree structure can significantly improve the query execution time in large data sets and multi-file structure can slightly improve the TPIE lover level building time.


Application Of Multi-Modal Fusion Techniques For Corrosion Detection And Characterization In Aging Aircraft Components, Soumya De Jan 2008

Application Of Multi-Modal Fusion Techniques For Corrosion Detection And Characterization In Aging Aircraft Components, Soumya De

Masters Theses

"The United States Air Force (USAF) recently estimated that corrosion maintenance costs exceed $800M per year. Given this, it is desirable to reduce the amount of "find it-fix it" corrosion maintenance activities. One method is to introduce a damage tolerance approach for corrosion detection. In order for this to become a reality, a comprehensive snapshot of corrosion present must be generated.

This thesis presents a data fusion process to perform uni- and multi-modal nondestructive testing and evaluation of corrosion under paint and in lap joints for volumetric characterization. The process for analyzing a given structure includes: 1) the acquisition of …


Formation Control Of Car-Like Mobile Robots, Shweta Annapurani Panimadai Ramaswamy Jan 2008

Formation Control Of Car-Like Mobile Robots, Shweta Annapurani Panimadai Ramaswamy

Masters Theses

"A traditional tracking and control design approach already available in literature is derived and discussed for a car-like mobile robot. It involves a decoupled design involving two separate algorithms, one for velocity control design and another for torque control design. Weak interactions among the algorithms and separate designs make the robot performance optimization and the formation stability difficult to achieve. So, a new tracking and control architecture wherein the conventional elements are replaced by a single component that performs all the functions and hence called the integrated tracking and control scheme is used"--Abstract, page iii.


Application Of Statcom For Improved Dynamic Performance Of Wind Farms In A Power Grid, Aditya P. Jayam Jan 2008

Application Of Statcom For Improved Dynamic Performance Of Wind Farms In A Power Grid, Aditya P. Jayam

Masters Theses

"This thesis investigates the use of a Static Synchronous Compensator (STATCOM) along with wind farms for the purpose of stabilizing the grid voltage after grid-side disturbances such as a three phase short circuit fault, temporary trip of a wind turbine and sudden load changes. The strategy focuses on a fundamental grid operational requirement to maintain proper voltages at the point of common coupling by regulating voltage. The DC voltage at individual wind turbine (WT) inverters is also stabilized to facilitate continuous operation of wind turbines during disturbances"--Abstract, page iii.


Universal Electric And Magnetic Fields Analyzer System, Yong Cheh Ho Jan 2008

Universal Electric And Magnetic Fields Analyzer System, Yong Cheh Ho

Masters Theses

"Near-field probing is often used to measure the electric and magnetic fields above a printed circuit board (PCB) or integrated circuits (IC) chip in order to identify the sources and coupling paths of an electromagnetic interference (EMI) problem.

A wideband universal field analyzer was designed, built and tested in this thesis. The system is able to provide fast field scanning over a wide frequency range in lieu of its capabilities to measure multiple field components using a single probe design. Central to the system operation is the phase-shifting concept that provides wideband and wide- range phase-shifting.

The complete universal field …


A Hybrid Sensor Network For Watershed Monitoring, John R. Koch Jan 2008

A Hybrid Sensor Network For Watershed Monitoring, John R. Koch

Masters Theses

"This thesis discusses the Hydrological Hybrid Communication Sensor Network (HHCSN), which is designed for in situ measurement of various hydrological properties of a watershed. HHCSN is comprised of a network of sensor strings, each of which connects up to 100 sensing nodes on a communication line as long as 100 m. Each node includes sensors that measure soil attributes of interest, as well as a microcontroller with basic communication and processing capabilities. A relay point at the surface compresses data from the nodes and wirelessly transmits it to a base station that serves as a gateway to the outside world. …


Statistical Estimation Of Crosstalk For Cable Bundles, Meilin Wu Jan 2008

Statistical Estimation Of Crosstalk For Cable Bundles, Meilin Wu

Masters Theses

"Predicting electromagnetic interference problems for cable bundles early in the design stage is of significant value for both automotive and other industries. Effective methods are needed for predicting interference when little design information is known. The random variation in parameters like wire position in the bundle require that statistical variations be taken into account. In the first part of this thesis, a method to analytically predict the "reasonable worst-case crosstalk" within a cable bundle is proposed. The method uses the per-unit-length LC matrices associated with the cross-sectional geometry of the bundle to generate probability a distribution function for mutual inductance …


Fabrication Of Long-Period Fiber Gratings By Co₂ Laser Irradiation For High Temperature Applications, Tao Wei Jan 2008

Fabrication Of Long-Period Fiber Gratings By Co₂ Laser Irradiation For High Temperature Applications, Tao Wei

Masters Theses

"Long period fiber gratings (LPFG) have unique advantages such as small insertion loss, low retro-reflection, good sensory property and low cost fabrication. LPFGs have found many applications in optical fiber communications as well as in optical fiber sensors. Recently, high-performance LPFGs have been successfully fabricated by CO₂ laser irradiations. The unique thermal stability enables many potential sensing applications in high temperature environments. In this thesis...two chemical sensing applications of LPFG were demonstrated. In the first one, the ambient refractive index sensing ability of bare LPFG was examined. The experimental data showed a good agreement with the simulation results. In the …


Block Level Link Path Design And Multilayer Via Transition Model Assembly Using S-Parameters, Francesco De Paulis Jan 2008

Block Level Link Path Design And Multilayer Via Transition Model Assembly Using S-Parameters, Francesco De Paulis

Masters Theses

"In high-speed data communication systems the complexity of link path between transmitters and receivers present a challenge for designers to maintain an acceptable bit error rate. An approach is presented in this thesis to design the link path on a block-by-block basis. The unique advantage of this approach lies on the physics-based model of each block, which then relates performance to geometry and makes design improvement and optimization possible. A tool based on the manipulation of frequency domain data has been designed to help in the design and analysis process of fast communication systems. It accepts as inputs the frequency …


Adaptive Modulation For Cognitive Radios, Gaurav Sharma Jan 2008

Adaptive Modulation For Cognitive Radios, Gaurav Sharma

Masters Theses

"This thesis examines the benefits of using adaptive modulation in terms of spectral efficiency and probability of bit error for cognitive radio networks. In channels that fluctuate dynamically over time, systems that are based upon the conventional methods of fixed modulation formats do not perform well. Adaptive modulation provides many parameters that can be adjusted relative to the channel fading, including data rate, transmit power, instantaneous BER, symbol rate, and channel code rate or scheme. In this thesis, a systematic study on the increase in spectral efficiency obtained by optimally varying combinations of the modulation formats for a cognitive radio …


Via Transition Modeling And Charge Replenishment Of The Power Delivery Network In Multilayer Pcbs, Matteo Cocchini Jan 2008

Via Transition Modeling And Charge Replenishment Of The Power Delivery Network In Multilayer Pcbs, Matteo Cocchini

Masters Theses

"In the first article of this thesis, the charge delivery in the power distribution network for printed circuit board has been analyzed in the time-domain. Performing all the simulations and analyzing the PDN physics and modeling, I contributed to a better understanding of the time-domain decoupling mechanism. The second paper studies the noise coupling sing a segmentation approach combined with a via-to-antipad capacitance model and a plane-pair cavity model. Building equivalent circuit models as well as analyzing design strategies, I contributed to a new approach for the PDN analysis in multilayer PCBs. The third article discusses how to estimate the …


Derivation Of New Double-Input Dc-Dc Converters Using The Building Block Methodology, Karteek Gummi Jan 2008

Derivation Of New Double-Input Dc-Dc Converters Using The Building Block Methodology, Karteek Gummi

Masters Theses

"In most power electronic systems, the instantaneous input and output power vary by time and are not exactly identical with each other. Hence, providing a good match between them is a complicated task to deal with if not impossible. Furthermore, due to the wide variation range of the processed power, the overall efficiency of the system is not high. The solution is to hybridize the system using an energy storage unit like in hybrid electric vehicles, power factor correction systems, and photovoltaic systems. Multi-input converters play a key role in such hybridized systems, where it is required to have more …