Engineering Commons^™

High Accuracy Distributed Target Detection And Classification In Sensor Networks Based On Mobile Agent Framework, Xiaoling Wang

Doctoral Dissertations

High-accuracy distributed information exploitation plays an important role in sensor networks. This dissertation describes a mobile-agent-based framework for target detection and classification in sensor networks. Specifically, we tackle the challenging problems of multiple- target detection, high-fidelity target classification, and unknown-target identification.

In this dissertation, we present a progressive multiple-target detection approach to estimate the number of targets sequentially and implement it using a mobile-agent framework. To further improve the performance, we present a cluster-based distributed approach where the estimated results from different clusters are fused. Experimental results show that the distributed scheme with the Bayesian fusion method have better performance …

A Two-Phase Cooling Method Using R134a Refrigerant To Cool Power Electronics Devices, Jeremy Bryant Campbell

Masters Theses

Power electronics are vital to the operation and performance of hybrid-electric vehicles (HEVs) because they provide the interface between the energy sources and the traction drive motor. As with any “real” system, power electronic devices have losses in the form of heat energy during normal switching operation, which has the potential ability to damage or destroy the device. Thus, to maintain reliability of the PE system, the heat energy produced must be removed. Present HEV cooling methods provide adequate cooling effects, but lack sufficient junction temperature control to maintain long-term reliability. This thesis is based on using the automobile’s air …

3d Sound Synthesis Using The Head Related Transfer Function, Dayu Yang

Masters Theses

Three-dimensional (3D) sound is a significant component of virtual reality. 3D sound systems or directional sound systems are designed to animate the sound space produced by real sound sources. In this thesis, basic concepts of 3D sound are introduced. The Head Related Transfer Functions (HRTFs) are analyzed in both the time and frequency domain. A 3D sound system is implemented using practical, measured HRTF data.

Hardware Acceleration Of The Embedded Zerotree Wavelet Algorithm, Suresh S. Polisetty

Masters Theses

The goal of this project was to gain experience in designing and implementing a microelectronic system to acclerate the execution of a time-consuming software algorithm, the Embedded Zerotree Wavelet (EZW), which is used in multimedia applications. The algorithm was implemented using MATLAB to be certain it was fully understood and to serve as a validation reference. Then, the algorithm was mapped into a hardware description language, VHDL, and its resulting implementation verified with the golden reference. The hardware description was then targeted to a field-programmable gate array (FPGA). Significant acceleration was achieved since the hardware implementation in a FPGA (Xilinx …

X-Ray Image Processing And Visualization For Remote Assistance Of Airport Luggage Screeners, Yue Zheng

Masters Theses

X-ray technology is widely used for airport luggage inspection nowadays. However, the ever-increasing sophistication of threat-concealment measures and types of threats, together with the natural complexity, inherent to the content of each individual luggage make x-ray raw images obtained directly from inspection systems unsuitable to clearly show various luggage and threat items, particularly low-density objects, which poses a great challenge for airport screeners.

This thesis presents efforts spent in improving the rate of threat detection using image processing and visualization technologies. The principles of x-ray imaging for airport luggage inspection and the characteristics of single-energy and dual-energy x-ray data are …

Curvature Variation As Measure Of Shape Information, Sreenivas Rangan Sukumar

Masters Theses

In this thesis, we present the Curvature Variation Measure (CVM) as our informational approach to shape description. We base our algorithm on shape curvature, and extract shape information as the entropic measure of the curvature. We present definitions to estimate curvature for both discrete 2D curves and 3D surfaces and then formulate our theory of shape information from these definitions.

With focus on reverse engineering and under vehicle inspection, we document our research efforts in constructing a scanning mechanism to model real world objects. We use a laser-based range sensor for the data collection and discuss view-fusion and integration to …

The Design Of Medium Access Control (Mac) Protocols For Energy Efficient And Qos Provision In Wireless Sensor Networks, Yang Liu

Masters Theses

This thesis work focuses on innovative design of media access control (MAC) protocols in wireless sensor networks (WNSs). The characteristics of the WSN inquire that the network service design considers both energy efficiency and the associated application requirement. However, most existing protocols address only the issue of energy efficiency.

In this thesis, a MAC protocol has been proposed (referred to as Q-MAC) that not only minimized the energy consumption in multi-hop WSNs, but also provides Quality of Service (QoS) by differentiating network services based on priority levels prescribed by different applications. The priority levels reflect the state of system resources …

Thermal Modeling And Imaging Of As-Built Automotive Parts, Vijaya Priya Muthusamy Govindasamy

Masters Theses

Simulation is of significant importance in the automotive industry and can be done for various applications ranging from fluid flow analysis to complex thermal management of components. This thesis describes the method and necessary requirements for thermal modeling of automotive parts. Simulation of under hood and under vehicle automotive poses several challenges, the shape and complexity of the geometry used being the first and foremost to be considered. This thesis addresses the simulation of thermal images of as-built automotive parts using the 3D meshes generated from 3D modeling tools, CAD meshes and reverse engineered meshes.

Thermal modeling requires complete knowledge …

A Mobile Virtual Reality System, Neena Nambiar

Masters Theses

Virtual Reality is the simulation of real or imagined environments, which can be experienced in three dimensions width, height and length. VR simulations provide interactions with the virtual world using external devices.

Virtual Reality systems have been bulky and not suitable for mobile operations. This thesis aims at creating such a mobile virtual reality system, which is portable and lightweight. This system consists of a lightweight notebook or laptop computer. It also includes a head-mounted display, a wireless mouse, a pinch glove, a tracker and wireless networking. This system is built with off-the-shelf components. This system is described in this …

Development Of An Fpga-Based Hardware Evaluation System For Use With Ga-Designed Artificial Neural Networks, Dennis Duncan Earl

Doctoral Dissertations

The Hardware-Evolved Digital Artificial Neural Network (HEDANN) design platform is a circuit design platform built to evolve complex architecture ANN circuits using re-configurable hardware. By using genetic algorithms to evolve complex architecture ANN designs in field programmable gate arrays, this system is the first design system to evolve physical ANN circuits with unconstrained network architectures. With the HEDANN design system, the evolution of ANNs with recursive, non-layered, complex architectural connections is made possible. In addition, the HEDANN design system is capable of evolving device-independent circuit designs that can operate properly across a wide range of operating temperatures. This system is …

Development Of Systemc Modules From Hdl For System-On-Chip Applications, Siddhartha Devalapalli

Masters Theses

Designs are becoming bigger in size, faster in speed and larger in complexity with the emergence of System-on-Chip designs. Hardware components and embedded software co-exist in such designs making it necessary to describe designs at higher levels of abstraction. Describing designs at higher levels of abstraction enables faster simulation, hardware software co-simulation and architectural exploration. SystemC is a solution.

Also the time to market can be reduced greatly if previously designed intellectually property (IP) described in a hardware description language (HDL) can be reused in SystemC.

In this research SystemC modules were successfully developed and verified from Verilog using existing …

Implementation Of Block-Based Neural Networks On Reconfigurable Computing Platforms, Sampath Kumar Kothandaraman

Masters Theses

Block-based Neural Networks (BbNNs) provide a flexible and modular architecture to support adaptive applications in dynamic environments. Reconfigurable computing (RC) platforms provide computational efficiency combined with flexibility. Hence, RC provides an ideal match to evolvable BbNN applications. BbNNs are very convenient to build once a library of neural network blocks is built. This library-based approach for the design of BbNNs is extremely useful to automate implementations of BbNNs and evaluate their performance on RC platforms. This is important because, for a given application there may be hundreds to thousands of candidate BbNN implementations possible and evaluating each of them for …

Calculated Combustion: An Investigation Of Electronic Equipment Tenability In Data Center Fires, Jeffrey Neal Krumm

Masters Theses

Fire presents a clear and present danger to computer equipment and generally results in tremendous expense or irreplaceable loss. This study serves as a proof of concept for using computer-based fire modeling to investigate the resilience of typical data center equipment to fire. In this analysis, the National Institute of Standards and Technology’s Fire Dynamics Simulator computer-based fire modeling tool is utilized to simulate fire scenarios within a rack-mount-style computer enclosure containing six circuit boards. Outcomes including effects of combustion (heat, mixture fraction, and species generation) and water-based sprinkler suppression are explored. Although the presence of standard water-based sprinkler suppression …

A Site-Specific Indoor Wireless Propagation Model, Chen Jin

Masters Theses

In this thesis, we explore the fundamental concepts behind the emerging field of site-specific propagation modeling for wireless communication systems. The first three chapters of background material discuss, respectively, the motivation for this study, the context of the study, and signal behavior and modeling in the predominant wireless propagation environments. A brief survey of existing ray-tracing based site-specific propagation models follows this discussion, leading naturally to the work of new model development undertaken in our thesis project. Following the detailed description of our generalized wireless channel modeling, various interference cases incorporating with this model are thoroughly discussed and results presented …

Boundary Layer Flow Acceleration By Paraelectric And Peristaltic Ehd Effects Of Aerodynamic Plasma Actuators, Madhan Raja Chandra Mohan

Masters Theses

Plasma actuators based on the OAUGDP TM (One Atmosphere Uniform Glow Discharge Plasma) promise to be a convenient method to modify aerodynamic boundary layers. The development of the OAUGD Plasma has made it possible to locate enough plasma actuators on airfoils and the wings and fuselage of aircraft to have significant effects on flow control and re-attachment at relatively low power cost. In this study OAUGD Plasma actuators have been used to effect flow re-attachment and to manipulate aerodynamic flows, possibly leading to improved methods of flight control. The OAUGDPTM actuators have been tested in the 7 x 11 Inch …

Bit Loading And Peak Average Power Reduction Techniques For Adaptive Orthogonal Frequency Division Multiplexing Systems, Jaideep Rajan Shahri

Masters Theses

In a frequency-selective channel a large number of resolvable multipaths are present which lead to the fading of the signal. Orthogonal frequency division multiplexing (OFDM) is well-known to be effective against multipath distortion. It is a multicarrier communication scheme, in which the bandwidth of the channel is divided into subcarriers and data symbols are modulated and transmitted on each subcarrier simultaneously. By inserting guard time that is longer than the delay spread of the channel, an OFDM system is able to mitigate intersymbol interference (ISI).

Significant improvement in performance is achieved by adaptively loading the bits on the subcarriers based …

Database Similarity Search In Metric Spaces: Limitations And Opportunities, Zeqian Shen

Masters Theses

Generic database similarity search is one of the most challenging problems in current database research. Generic data are not simply structured data with several keys of numeric or alphabetic types. Traditional search algorithms that only check specified fields and keys are not effective. Similarity searches find the objects that are similar to a target using a specified similarity criterion. Tree-structured indexing techniques based on metric spaces are widely used to solve this problem. Existing methods can be divided into two categories: approaches based upon Voronoi partitions and approaches based upon reference points. The later one is the focus of this …

An Experimental Model Of Ball Lightning, Madras Parameswaran Sriram

Masters Theses

A form of ball lightning was generated in the laboratory. Plasma spheres several centimeters in diameter were produced in atmospheric pressure air. These spheres persisted up to ½ a second after power turn –off. A mathematical model was derived that predicts the observed lifetime. The theory predicts that the sphere lifetime should scale as the radius squared, which means large spheres should exist for many seconds. We also generated ball lightning in a zero gravity environment. The object was to eliminate convection, which had been observed to reduce the size of a ball generated by a two – dimensional electric …

An Open Core System-On-Chip Platform, Rishi R. Srivastava

Masters Theses

The design cycle required to produce a System-on-Chip can be reduced by providing pre-designed built-in features and functions such as configurable I/O, power and ground grids, block RAMs, timing generators and other embedded intellectual property (IP) blocks. A basic combination of such built-in features is known as a platform.

The major objective of this thesis was to design and implement one such System-on-Chip platform using open IP cores targeting the TSMC-0.18 CMOS process.

The integrated System-on-Chip platform, which contains approximately four million transistors, was synthesized using Synopsys - Design Compiler and placed and routed using Cadence - First Encounter, …

A Characteristic Study Of The Atmospheric Pressure Nonthermal Resistive Barrier Plasma Discharge For Biological Decontamination, Magesh Thiyagarajan

Masters Theses

Steady-state atmospheric pressure nonthermal plasmas can splendidly debilitate bacteria in liquids, gases and on surfaces, as well as can disintegrate hazardous chemicals. The nonthermal gas discharge at atmospheric pressure, such as resistive barrier discharge is investigated for low temperature sterilization purposes. In specific, exploring and understanding the hidden secrets of the plasma sterilization mechanisms and the intensification of the main microbial reduction pathways are the objectives of the research.

A dual-mode steady-state atmospheric pressure resistive barrier ionized gas (plasma) generator has been designed and developed to meet the environmental health and federally mandated safety standards. Electrical, chemical, optical, and biological …

\A Ro- Bust Node Selection Strategy For Lifetime Extension In Wireless Sensor Networks, Olawoye A. Oyeyele

Masters Theses

Distributed Wireless Sensor Networks (WSNs) consist of energy-constrained sensor nodes that may be deployed in large numbers in order to monitor a given area, track military targets, detect civilian targets or for other purposes. In such densely deployed environments, multiple transmissions can lead to collisions resulting in packet losses and network congestion. This can increase latency and reduce energy efficiency. These networks also feature significant redundancy since nodes close to each other often sense similar data. Therefore, it may be adequate to employ only a subset of the deployed nodes at any given time in the network. In this thesis, …

An Experimental Study Of The Accuracy Of Multiple Power Estimation Methods, Ashwin Balakrishnan

Masters Theses

New and complex systems are being implemented using highly advanced Electronic Design Automation (EDA) tools. As the complexity increases, the dissipation of power has emerged as one of the very significant design constraints. Low power designs are not only used in small size applications like cell phones and handheld devices but also in high-performance computing applications.

Numerous tools have emerged in recent years to address this issue of power consumption and power optimization. With a vast number of these power measurement tools emerging, analyzing power consumed by digital circuits has not only become easier but also more effective methods are …

Space-Time Codes Concatenated With Turbo Codes Over Fading Channels, Junghoon Suh

Doctoral Dissertations

The uses of space-time code (STC) and iterative processing have enabled robust communications over fading channels at previously unachievable signal-to-noise ratios. Maintaining desired transmission rate while improving the diversity from STC is challenging, and the performance of the STC suffers considerably due to lack of channel state information (CSI). This dissertation research addresses issues of considerable importance in the design of STC with emphasis on efficient concatenation of channel coding and STC with theoretical bound derivation of the proposed schemes, iterative space-time trellis coding (STTC), and differential space-time codes.

First, we concatenate space-time block code (STBC) with turbo code for …

Automated Exploration Of The Asic Design Space For Minimum Power-Delay-Area Product At The Register Transfer Level, Fuat Karakaya

Doctoral Dissertations

Exploring the integrated circuit design space for minimum power-delay-area (PDA) product can be time-consuming and tedious, especially when the target standard-cell library has hundreds of options. In this dissertation, heuristic algorithms that automate this process have been developed, implemented and validated at the reg- ister transfer level. In some cases, the PDA product was 1.9 times better than the initial baseline solution. The parallel search algorithm exhibited 9x speed up when executed on 10 machines simultaneously. These two new methods also characterize the design space for the given RTL code by generating power-delay-area points in addition to the minimum PDA …

G4-Fet Based Voltage Reference, Suheng Chen

Masters Theses

A precise and stable voltage reference is essential to analog/mixed-signal SoC (system-on-a-chip) applications. The most commonly used voltage reference in standard CMOS processes, the bandgap voltage reference, is limited due to output drift in wide temperature range applications. The temperature drift associated with the bandgap voltage reference is non-linear, thus temperature compensation is difficult. A new reference circuit, the JFET-based voltage reference, is proven to be more temperature stable. However, the JFET-based voltage reference requires a specialized Bi-CMOS process with additional fabrication steps to alter the channel doping for selected devices. The purpose of this thesis is to investigate the …

Hyper-Spectral Image Processing Using High Performance Reconfigurable Computers, Yuan He

Masters Theses

The purpose of this thesis is to investigate the methods of implementing a section of a Matlab hyper-spectral image processing software application into a digital system that operates on a High Performance Reconfigurable Computer. The work presented is concerned with the architecture, the design techniques, and the models of digital systems that are necessary to achieve the best overall performance on HPRC platforms. The application is an image-processing tool that detects the tumors in a chicken using analysis of a hyper-spectral image. Analysis of the original Matlab code has shown that it gives low performance in achieving the result. The …

Design And Implementation Of An All Digital Phase Locked Loop Using A Pulse Output Direct Digital Frequency Synthesizer, Akila Gothandaraman

Masters Theses

Phase Locked Loops (PLLs) are widely used in clock recovery and frequency synthesis. Fully Digital PLLs are more suitable for the monolithic implementation with other circuits compared to the traditional implementations of the PLLs. The All Digital PLLs are also independent of process variations and can be easily ported to different technologies.

This thesis presents the design of an All Digital Phase Locked Loop (ADPLL) using a pulse output Direct Digital Frequency Synthesizer (DDFS) and an All Digital Phase Frequency Detector (ADPFD). General design criteria are summarized for the all digital implementation in comparison to the traditional approaches and analog …

Combined Mutual Information Of Intensity And Gradient For Multi-Modal Medical Image Registration, Wei Jiang

Masters Theses

In this thesis, registration methods for multi-modal medical images are reviewed with mutual information-based methods discussed in detail. Since it was proposed, mutual information has gained intensive research and is getting very popular, however its robustness is questionable and may fail in some cases. The possible reason might be it does not consider the spatial information in the image pair. In order to improve this measure, the thesis proposes to use combined mutual information of intensity and gradient for multi-modal medical image registration. The proposed measure utilizes both the intensity and gradient information of an image pair. Maximization of this …

Eliminating Harmonics In A Cascaded H-Bridges Multilevel Inverter Using Resultant Theory, Symmetric Polynomials, And Power Sums, Keith Jeremy Mckenzie

Masters Theses

This thesis studies a multilevel converter with assumed equal dc sources. The multilevel fundamental switching scheme is used to control the needed power electronics switches. Also, a method is presented where switching angles are computed such that a desired fundamental sinusoidal voltage is produced while at the same time certain higher order harmonics are eliminated.

Using Fourier Series theory, the transcendental equations eliminating certain higher order harmonics were derived in terms of the switching angles. Furthermore, these transcendental equations were transformed into polynomial equations by making some simple changes of variables. Resultant theory was used to solve the polynomial equations. …

A Reconfigurable Computing Solution To The Parameterized Vertex Cover Problem, Dorai Mahesh

Masters Theses

Active research has been done in the past two decades in the field of computational intractability. This thesis explores parallel implementations on a RC (reconfigurable computing) platform for FPT (fixed-parameter tractable) algorithms.

Reconfigurable hardware implementations of algorithms for solving NP-Complete problems have been of great interest for research in the past few years. However, most of the research that has been done target exact algorithms for solving problems of this nature. Although such implementations have generated good results, it should be kept in mind that the input sizes were small. Moreover, most of these implementations are instance-specific in …