Electrical and Electronics Commons^™

High Temperature Packaging For Wide Bandgap Semiconductor Devices, Brian Grummel

Electronic Theses and Dissertations

Currently, wide bandgap semiconductor devices feature increased efficiency, higher current handling capabilities, and higher reverse blocking voltages than silicon devices while recent fabrication advances have them drawing near to the marketplace. However these new semiconductors are in need of new packaging that will allow for their application in several important uses including hybrid electrical vehicles, new and existing energy sources, and increased efficiency in multiple new and existing technologies. Also, current power module designs for silicon devices are rife with problems that must be enhanced to improve reliability. This thesis introduces new packaging that is thermally resilient and has reduced …

Audio And Video Tempo Analysis For Dance Detection, Ryan Faircloth

Electronic Theses and Dissertations

The amount of multimedia in existence has become so extensive that the organization of this data cannot be performed manually. Systems designed to maintain such quantity need superior methods of understanding the information contained in the data. Aspects of Computer Vision deal with such problems for the understanding of image and video content. Additionally large ontologies such as LSCOM are collections of feasible high-level concepts that are of interest to identify within multimedia content. While ontologies often include the activity of dance it has had virtually no coverage in Computer Vision literature in terms of actual detection. We will demonstrate …

Inter-Satellite Microwave Radiometer Calibration, Liang Hong

Electronic Theses and Dissertations

The removal of systematic brightness temperature (Tb) biases is necessary when producing decadal passive microwave data sets for weather and climate research. It is crucial to achieve Tb measurement consistency among all satellites in a constellation as well as to maintain sustained calibration accuracy over the lifetime of each satellite sensor. In-orbit inter-satellite radiometric calibration techniques provide a long term, group-wise solution; however, since radiometers operate at different frequencies and viewing angles, Tb normalizations are made before making intermediate comparisons of their near-simultaneous measurements. In this dissertation, a new approach is investigated to perform these normalizations from one satellite's measurements …

Literature And Performance Of Music For Double Bass And Tape, Jeremy C. Baguyos

Music Faculty Publications

Electroacoustic music for double bass can be classified into the following two types of repertoire: real-time/interactive computer music or tape music. Real-time/interactive computer music is the newer of the two types and involves the algorithmic generation of electronic sounds in live performance. Pre-recorded electronic sounds are usually avoided, and instead, the sound of live input is used as the source material for electronic sounds. A computer is used for capture, processing and synthesis, and the software is usually written in the MAX/MSP environment. The second category, tape music, is the older of the two types of electroacoustic music for the …

Comparison Of Theoretical Models Of Power Spectral Density To The Experimental Value For Spectrum Of Irradiance Fluctuations, Craig Hershberger

Electronic Theses and Dissertations

A propagation experiment was designed, assembled, and conducted on an extended range to verify theoretical temporal models for weak to strong fluctuation theory. Laser light intensity was propagated over terrain at the Kennedy Space Center (Florida), and detected using optical receivers at a distance of 13.3 Km from the optical source. The intensity data from the experiment was used to generate an experimental Power Spectral Density (PSD) function. The theoretical Mutual Coherence Function (MCF) and Wave Structure Function (WSF) as set forth by Andrews/Phillips , were evaluated to determine the effective relationship between the statistical moments of the random optical …

Data Communication With A Nano-Satellite Using Satellite Personal Communication Networks (S-Pcns), Khudeja Khan

Electronic Theses and Dissertations

Satellites typically communicate with locations on the ground to receive commands and send data back. Establishing reliable communications generally requires dedicated ground stations, which in turn require hardware and expertise. Developers of nano-satellites, however, may not have the expertise or resources necessary for establishing a dedicated ground station. Therefore, the use of an existing communication system, such as the Satellite Personal Communication Networks (S-PCNs), is attractive. Another shortcoming of the fixed ground stations, already available, is that they are normally only able to communicate with Low Earth Orbit (LEO) nano-satellites four times per day (two10-minute windows separated by 90 minutes, …

A Multi-Objective No-Regret Decision Making Model With Bayesian Learning For Autonomous Unmanned Systems, Matthew Howard

Electronic Theses and Dissertations

The development of a multi-objective decision making and learning model for the use in unmanned systems is the focus of this project. Starting with traditional game theory and psychological learning theories developed in the past, a new model for machine learning is developed. This model incorporates a no-regret decision making model with a Bayesian learning process which has the ability to adapt to errors found in preconceived costs associated with each objective. This learning ability is what sets this model apart from many others. By creating a model based on previously developed human learning models, hundreds of years of experience …

Novel Complex Adaptive Signal Processing Techniques Employing Optimally Derived Time-Varying Convergence Factors With Applicatio, Raghuram Ranganathan

Electronic Theses and Dissertations

In digital signal processing in general, and wireless communications in particular, the increased usage of complex signal representations, and spectrally efficient complex modulation schemes such as QPSK and QAM has necessitated the need for efficient and fast-converging complex digital signal processing techniques. In this research, novel complex adaptive digital signal processing techniques are presented, which derive optimal convergence factors or step sizes for adjusting the adaptive system coefficients at each iteration. In addition, the real and imaginary components of the complex signal and complex adaptive filter coefficients are treated as separate entities, and are independently updated. As a result, the …

A Low Phase Noise K-Band Oscillator Utilizing An Embedded Dielectric Resonator On Multilayer High Frequency Laminates, Ajay Subramanian

Electronic Theses and Dissertations

K-Band (18 to 26 GHz) dielectric resonator oscillators are typically used as a local oscillator in most K-Band digital transmitter/receiver topologies. Traditionally, the oscillator itself is made up of an active device, a dielectric resonator termination network, and a passive load matching network. The termination network embodies a cylindrical high permittivity dielectric resonator that is coupled on the same plane as a current carrying transmission line. This configuration provides an adequate resonance needed for oscillation but has some limitations. In order to provide a high Q resonance the entire oscillator is placed in a metal box to prevent radiation losses. …

A Time-Varying Radiometric Bias Correction For The Trmm Microwave Imager, Kaushik Gopalan

Electronic Theses and Dissertations

This dissertation provides a robust radiometric calibration for the TRMM Microwave Imager to correct systematic brightness temperature errors, which vary dynamically with orbit position (time) and day of the year. The presence of a time-varying bias in TMI is confirmed by inter-calibration with WindSat and SSMI. This time varying bias is manifested as a time of day dependent variation of the relative biases between TMI and both WindSat and SSMI. In this dissertation, we provide convincing evidence that this time-varying Tb bias in TMI is caused by variations in the physical temperature of the emissive TMI reflector antenna. This dissertation …

Integration Of A Nanostructure Embedded Thermoresponsive Polymer For Microfluidic Applications, Ghanashyam Londe

Electronic Theses and Dissertations

This work describes the modeling, synthesis, integration and characterization of a novel nanostructure embedded thermoresponsive material for microfluidic applications. The innumerable applications of thermoresponsive surfaces in the recent years have necessitated the development of a rigorous mathematical treatment for these surfaces to understand and improve their behavior. An analytical model is proposed to describe the transfer characteristic (variation of contact angle versus temperature) of a unique switchable, nanostructured, thermoresponsive surface consisting of silica nanoparticles and the thermoresponsive polymer, Poly(N-isopropylacrylamide ) (PNIPAAm) which changes its wetting angle upon heating. Important metrics such as the absolute lower critical solution temperature, threshold & …

Real-Time Trajectory Planning For Groundand Aerial Vehicles In A Dynamic Environment, Jian Yang

Electronic Theses and Dissertations

In this dissertation, a novel and generic solution of trajectory generation is developed and evaluated for ground and aerial vehicles in a dynamic environment. By explicitly considering a kinematic model of the ground vehicles, the family of feasible trajectories and their corresponding steering controls are derived in a closed form and are expressed in terms of one adjustable parameter for the purpose of collision avoidance. A collision-avoidance condition is developed for the dynamically changing environment, which consists of a time criterion and a geometrical criterion. By imposing this condition, one can determine a family of collision-free paths in a closed …

Numerical Modeling Of Wave Propagation In Nonlinear Photonic Crystal Fiber, Md. Kaisar Khan

Electronic Theses and Dissertations

In this dissertation, we propose numerical techniques to explain physical phenomenon of nonlinear photonic crystal fiber (PCF). We explain novel physical effects occurred in PCF subjected to very short duration pulses including soliton. To overcome the limitations in the analytical formulation for PCF, an accurate and efficient numerical analysis is required to explain both linear and nonlinear physical characteristics. A vector finite element based model was developed to precisely synthesize the guided modes in order to evaluate coupling coefficients, nonlinear coefficient and higher order dispersions of PCFs. This finite element model (FEM) is capable of evaluating coupling length of directional …

Teaching And Assessment Of Students Taking A First Year, Level 7 Subject: Analysis And Actions, Aidan O'Dwyer

Conference papers

This contribution critically analyses the teaching and assessment strategies used on the core Electrical Systems subject in the first year of a three-year, Level 7, degree programme in Electrical Engineering at Dublin Institute of Technology. The author has the responsibility for development and instruction in the subject since 2004. In the 2004-5 and 2005-6 academic years, the didactic teaching approach and the assessment strategy ensured good educational outcomes. This was not the case in the 2006-7 academic year. The contribution will analyse the reasons for this, taking an evidence-based approach (i.e. analysing the assessment data in detail). Two conclusions that …

Antennas For Portable Communications In The Uwb And Gps Spectra., Giuseppe Ruvio

Doctoral

The thesis describes a study of antennas for solutions in emerging systems. An account of the fundamental principles of these antennas is given together with an outline of the basic electromagnetic theory on which the designs are based. While the main focus is on antennas for Ultra Wideband (UWB) systems, some additional work was carried out on enhancing performance of circularly polarised antennas for satellite navigation systems. The study focussed on the design of highly efficient broadband antennas with particular requirements for size compactness, gain stability, phase-linearity, and the use of low-cost materials. These requirements are particularly important for UWB …

A Distributed Ai Approach For Large-Scale Wlan Design, Alan Mcgibney

Theses

The recent dramatic trend towards always-on-connectivity has driven the need for mobile ubiquitous computing environments with the advent of the Wireless Local Area Network (WLAN) seeing a shift from traditional wired networks to wireless networking. A WLAN typically contains a number of access points that allow wireless enabled clients access information and network resources such as the internet without the need for wires, offering flexibility and mobility to the users. Initial wireless networks were convenience based allowing users access to the primary wired network, and involved little planning prior to roll-out. The proliferation of low cost wireless devices combined wdth …

Design, Implementation And Evaluation Of A Networking Context Aware Policy Environment, Asanga Dhammika Udugama

Theses

Future mobile networks are anticipated to have support to access heterogeneous access technologies. An important question in such environments is the decisions on when to use what access network. These decisions must take the users and mobile network operators’ perspectives into consideration. The operators usually have a focus of always-best-managed networks while the users have an always-best-connected focus. A key enabler of such environments is the use of policies to perform these handover decisions. These policies, which must be dynamic in nature, should be configurable when the requirements change. Policy decisions are always made based on the current context of …

Elliptic Curve Cryptography Security On Restricted Mobile Devices, Debbie Mccann

Theses

Mobile technologies with limited resources, such as smart phones or PDAs, have increased dramatically in popularity. However, the level of security provided for these technologies has not kept pace with the value of the data that they contain or transmit.

Wireless networks usually provide some security, in the form of encryption. GSM and GPRS use different forms of the A5 algorithm, and Wi-Fi uses WEP or WPA. These encryption algorithms have proven weaknesses and in some cases have been efficiently cracked. To improve the security of wireless networks, stronger encryption algorithms need to be developed. One of the most attractive …

Mesh Mac Enabling Mesh Networking Over Ieee 802.15.4 Mac Layer, Panneer Selvan Muthukumaran

Theses

Wireless sensor network is a network of sensor nodes that function in a cooperative manner to monitor the changes in the physical environment. Wireless sensor networks are used in environment and habitat monitoring, healthcare applications, building automation, and traffic control to name a few. Typically, wireless sensor node is a low power embedded device which consists of a microcontroller, sensors, wireless transceiver and a battery. These devices are usually distributed in a physical environment which makes it difficult to maintain the network manually.

The IEEE 802.15.4 and Zigbee are considered as standard protocols for wireless sensor networks. The IEEE 802.15.4 …

A Novel Expanded 16-Dimensional Constant Envelope Q2psk Constellation, Milton I. Quinteros, Kenneth V. Cartwright, Edit J. Kaminsky, Ricardo U. Gallegos

Electrical Engineering Faculty Publications

We introduce a 16-dimensional constant-amplitude constellation that is generated by concatenating either four constant envelope quadrature-quadrature phase shift keying (CEQ2PSK) symbols from Saha and Birdsall or four CEQ2PSK symbols recently discovered by Cartwright and also introduced here. Our new constellation doubles the number of points available for data transmission without decreasing the distance between points or increasing energy, and may therefore be used in a trellis coded modulation (TCM) system without constellation expansion penalty. Because the new constellation has constant envelope, the modulation scheme becomes very attractive for nonlinear channels such as the magnetic recording channel or the satellite channel …

Classification Of Cylindrical Targets Buried In Seafloor Sediments, Edit J. Kaminsky, Madalina Barbu

Electrical Engineering Faculty Publications

This paper presents the development and evaluation of a time-frequency processing technique for detection and classification of buried cylindrical targets from chirpbased parametric sonar data. The software is designed to discriminate between cylindrical targets —such as cables— of different diameters, which need to be identified as different from other strong reflectors or point targets. The method is evaluated on synthetic data generated with an acoustic scattering model for elastic cylinders for seven different diameters. The model generates characteristic responses of targets acquired by a parametric sonar system. The signal at the sonar receiver hydrophones is first windowed to reduce the …

Drop Photometer Design., Kevin Tiernan

Doctoral

The tensiograph drop analyser, operating in the mode of ultraviolet-visual absorption photometer, was re-engineered to improve measurement accuracy. As well as instrumentation re-design, the other objective of the research was to analyse tensiograph signals to explore how their features are defined by drop properties. Using fibre optic technology, the tensiograph emits a light beam into a growing pendant drop whereupon it undergoes a number of internal reflections. A portion of the reflected light energy is coupled to a photodiode producing a proportional current that is electronically processed and transferred to a computer for analysis. The signal produced, known as the …

Evaluation Of An Image Processing Algorithm For Scene Change Detection, Daniel Flores

Open Access Theses & Dissertations

Despite the efforts to reduce traffic accidents by government entities and automobile manufactures, the numbers of accidents are not considerably reduced. An evaluation of an algorithm based on the fly's eye is done on this research applying its principles to detect scene change on images for printed circuit boards providing initial steps to implement this algorithm on vehicular traffic to keep track of objects moving on the field for collision avoidance purposes. The effectiveness of the algorithm is addressed through a comparison of its performance with that found in experimental data.

Kilovolt Blumlein Pulse Generator With Variable Pulse Duration And Polarity, Andrea De Angelis, Juergen F. Kolb, Luigi Zeni, Karl H. Schoenbach

Bioelectrics Publications

A Blumlein pulse generator which utilizes the superposition of electrical pulses launched from two individually switched pulse forming lines has been designed and tested. By using a power metal-oxide-semiconductor field-effect transistor as a switch on each end of the Blumlein line, we were able to generate pulses with amplitudes of 1kV across a 100Ω load. Pulse duration and polarity can be controlled by the temporal delay in the triggering of the two switches. Using this technique, we have demonstrated the generation of pulses with durations between 8 and 60ns. The lower limit in pulse duration was determined by the switch …

Phonon-Energy-Coupling-Enhancement Effect And Its Applications, Pang-Leen Ong

University of Kentucky Doctoral Dissertations

Silicon Oxide/Oxynitride (SiO₂/SiON) has been the mainstream material used for gate dielectric for MOS transistors for the past 30 years. The aggressive scaling of the feature size of MOS transistor has limited the ability of SiO₂/SiON to work effectively as the gate dielectric to modulate the conduction of current of MOS transistors due to excess leakage current dominated by direct quantum tunneling. Due to this constraint, alternative gate dielectric/high-k is being employed to reduce the leakage current in order to maintain the rate of scaling of MOS transistors. However, the cost involved in the implementation of …

A Mobile Ecg Monitoring System With Context Collection, Jin Peng Li

Masters

An objective of a health process is one where patients can stay healthy with the support of expert medical advice when they need it, at any location and any time. An associated aim would be the development of a system which places increased emphasis on preventative measures as a first point of contact with the patient. This research is a step along the road towards this type of preventative healthcare for cardiac patients. It seeks to develop a smart mobile ECG monitoring system that requests and records context information about what is happening around the subject when an arrhythmia event …

Dual Bypass Gas Metal Arc Welding Process And Control, Xiaopei Liu

University of Kentucky Doctoral Dissertations

GMAW (Gas Metal Arc Welding) is one of the most important arc welding processes being adopted in modern manufacturing industry due to its advantages in productivity, energy efficiency and automation. By monitoring and improving some of the important properties of GMAW such as production rate, metal transfer and base metal heat input, researchers could bring the process efficiency and stability to a new level. In recent years, some innovative modifications of GMAW such as Twins, Tandem and laser-MIG hybrid welding have been adopted into many industrial applications for better productivity.

In this dissertation, a novel GMAW called DB-GMAW (Dual Bypass …

Guidelines For Deploying Wireless Sensor Network In Manufacturing: Star Topology Study Using The Rssi To Test The Network Performance, A. Hameed Madwar

Dissertations and Theses @ UNI

Wireless Sensor Networks (WSNs) are varying in kinds and can be used for many purposes. It can be extensively used in monitoring, reporting, and decision routines. Therefore, WSNs are very important to integrate with manufacturing since they can help not only in monitoring and decision making but also they can increase productivity and decrease the wiring costs. However, WSNs are facing some challenges in manufacturing as they need to resist the interferences that could be generated by the electrical and mechanical fields created during the manufacturing processes. Some of these interferences could be due to the high temperatures, blocks of …