Engineering Commons^™

Improved Content Based Watermarking For Images, Arvind Kumar Parthasarathy

LSU Master's Theses

Due to improvements in imaging technologies and the ease with which digital content can be created and manipulated, there is need for the copyright protection of digital content. It is also essential to have techniques for authentication of the content as well as the owner. To this end, this thesis proposes a robust and transparent scheme of watermarking that exploits the human visual systems’ sensitivity to frequency, along with local image characteristics obtained from the spatial domain, improving upon the content based image watermarking scheme of Kay and Izquierdo. We implement changes in this algorithm without much distortion to the …

Design Of Linear Boolean Network Codes For Combination Networks, Shoupei Li

LSU Master's Theses

Network coding is a promising technique to improve the throughput of communication networks. In the thesis, we investigate linear Boolean network codes on a special class of multicast networks, called combination networks. Using companion matrices of primitive polynomials over finite fields, we design a class of symmetric linear Boolean network codes from Reed-Solomon codes for single-source combination networks. We also prove that, for some cases, the linear Boolean network codes are optimal in the sense of minimum network uses. In the thesis, we further consider two-source network coding problem for combination networks and other specific networks. We develop a method …

Em Algorithm For Multiple Wideband Source Localization, Kiran Kumar Mada

LSU Master's Theses

A computationally efficient algorithm using the expectation-maximization (EM) algorithm for multiple wideband source localization in the near field of a sensor array/area is addressed in this thesis. Our idea is to decompose the observed sensor data, which is a superimposition of multiple sources, into the individual components in the frequency domain and then estimate the corresponding location parameters associated with each component separately. Instead of the conventional alternating projection (AP) method, we propose to adopt the EM algorithm in this work; our new method involves two steps, namely Expectation (E-step) and Maximization (M-step). In the E-step, the individual incident source …

Radio Frequency Enabled Soil Redox Potential Sensor Networks, Chris Holme

Theses : Honours

There is a need for' cost effective tools and data collection methods for field measurements; to increase both productivity and volumes of collected data in the quest for enhanced understanding and management of environmental systems. To such end, various technologies that may be combined into a cost effective soil redox sensor network were explored. Suitability of each technology, as a component of said network was evaluated. A prototype soil redox sensor network was constructed and basic laboratory and field testing was completed. Results indicate that the prototype sensor network functions correctly within bounds. Both laboratory and field testing show that …

Stability Analysis Of Hybrid Jump Linear Systems With Markov Inputs, Arturo Tejada Ruiz

Electrical & Computer Engineering Theses & Dissertations

In the past two decades, the number of applications that make use of supervisory algorithms to control complex continuous-time or discrete-time systems has increased steadily. Typical examples include air traffic management, digital control systems over networks, and flexible manufacturing systems. A common feature of these applications is the intermixing of the continuous dynamics of the controlled plant with the logical and discrete dynamics of the supervising algorithms. These so-called hybrid systems are the focus of much ongoing research. To improve the performance of these systems, it is important to analyze the interactions between the supervising algorithms and the plant. Few …

Automatic Speech Recognition Using Lp-Dctc/Dcs Analysis Followed By Morphological Filtering, Penny Hix

Electrical & Computer Engineering Theses & Dissertations

Front-end feature extraction techniques have long been a critical component in Automatic Speech Recognition (ASR). Nonlinear filtering techniques are becoming increasingly important in this application, and are often better than linear filters at removing noise without distorting speech features. However, design and analysis of nonlinear filters are more difficult than for linear filters. Mathematical morphology, which creates filters based on shape and size characteristics, is a design structure for nonlinear filters. These filters are limited to minimum and maximum operations that introduce a deterministic bias into filtered signals.

This work develops filtering structures based on a mathematical morphology that utilizes …

Robustness And Control Of A Magnetically Levitated Transportation System, Grzegorz Oleszczuk

Mechanical & Aerospace Engineering Theses & Dissertations

Electromagnetic suspension of Magnetic Levitation Vehicles (Maglev) has been studied for many years as an alternative to wheel-on rail transportation systems. In this work, design and implementation of control systems for a Maglev laboratory experiment and a Maglev vehicle under development at Old Dominion University are described. Both plants are modeled and simulated with consideration of issues associated with system non-linearity, structural flexibility and electromagnetic force modeling. Discussion concerning different control strategies, namely centralized and decentralized approaches are compared and contrasted in this work. Different types of electromagnetic non-linearities are considered and described to establish a convenient method for modeling …

Femtosecond Laser Ablation With Single And Two-Photon Excitation For Mems, Mohamed Abdelfattah Kottb Ahmad Elbandrawy

Electrical & Computer Engineering Theses & Dissertations

There is an increasing interest in femtosecond laser micromachining of materials because of the femtosecond laser's unique high peak power, ultrashort pulse width, negligible heat conductivity process during the laser pulse, and the minimal heat affected zone, which is in the same order of magnitude of the ablated submicron spot. There are some obstacles in reaching optimal and reliable micromachining parameters. One of these obstacles is the lack of understanding of the nature of the interaction and related physical processes. These processes include amorphization, melting, re-crystallization, nucleated-vaporization, and ablation.

The focus of this Dissertation was to study the laser-matter interaction …

Diverse Effects Of Nanosecond Pulsed Electric Fields On Mammalian Cells, Jody Anne White

Theses and Dissertations in Biomedical Sciences

The continuing effort to manipulate cell-signaling pathways for therapeutic benefit has lead to the exploration of electric field effects on cells. Current electric field applications include electroporation of the plasma membrane for introduction of drugs, genes, or other macromolecules into cells. Modeling of how these pulsed electric fields affect cells depicts the cell as an excitable circuit. In this model, the electric fields, administered in short pulses to a cell, charge the plasma and internal membranes, which act as dielectric layers, and between these the cytoplasm acts as a conductive medium. The pulse lengths of this treatment are traditionally in …

System Analysis And Rf-Floodlight Exploitation Of Short-Range Gotcha Repeaters, Jose A. Montes De Oca

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Emerging wide-area synthetic aperture radar (SAR) system concepts call for a single data collection platform to orbit a large ( e.g., 20-km) spot at a nominal range of 40-km. The large standoff distance and desire for fine resolution, coupled with a need for persistent real-time sensing, pose a significant challenge in terms of clutter-to-noise ratio (CNR) performance and data processing. Increased CNR and reduced processing load can be achieved by decreasing the range of the SAR system and the size of the area of interest. Employing multiple cooperating SAR systems allows the same overall coverage area to be maintained …

Digital Channelized Wide Band Receiver Implemented With A Systolic Array Of Multi-Rate Fir Filters, David M. Rodney

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This thesis proposes the use of a Systolic Array of Multi-Rate FIR Filters to improve performance by eliminating the requirement of the FFT and De-Multiplexer associated with the conventional receiver while achieving the same functionality. The FFT is a major bottle neck for improving system performance for the conventional DCWBR because many complex multiplications and additions are required. The proposed new architecture is designed and evaluated in MATLAB to illustrate its viability. Two approaches for improved channel arbitration are accessed in MATLAB, namely, channel bin’s rms comparison and parallelism of the Systolic Array Multi-Rate FIR Filters. The FIR filters (high-pass …

Design And Evaluation Of A Discrete Wavelet Transform Based Multi-Signal Receiver, Tony Chiang

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General purpose receivers of today are designed with a broad bandwidth so that the receiver can accept a wide range of signal frequencies. These receivers usually accept one signal along with any interference that is included. To increase the signal detection capabilities of the wideband receiver, a design for a receiver that can detect two signals is needed. One of the requirements for this receiver is that the second weak signal needs to be processed in a timely manner so that the receiver can recognize it. To remedy the problem, a module was developed using wavelet-based techniques to remove spurs …

Implementation Of A Multi-Layered Fuzzy Controller On An Fpga, Ajit Paal Singh Khatra

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The uses of Autonomous Mobile robots range from the teleoperated Sojourner on the Mars Pathfinder mission to cleaning robots in the Paris Metro. They have overtaken tasks which are too difficult or dangerous to perform or require the repetition of the same procedure over and over again and can become dull for a human to perform. The objective of this thesis is to develop and implement a multilayered fuzzy controller on an FPGA for the navigational control of an autonomous mobile robot (AMR). The navigational algorithm assists the robot in navigating through complex environments of passages and hallways. The FPGA …

Direct Digital Frequency Synthesizer Implementation Using A High Speed Rom Alternative In Ibm 0.13u Technology, Matthew R. Gerald

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The direct digital synthesizer is a method of signal generation with many benefits. DDS designs are able to switch frequencies very quickly and also tune precisely to many different frequencies with the use of a constant operating frequency. There is a need for a low power, high speed DDS in the form an ASIC design. One major bottleneck in common DDS systems is the slow access time of a ROM. There is also a need for a high speed ROM alternative. This thesis delivers a high speed ASIC Direct Digital Synthesizer which operates at a 1 GHz operating frequency. This …

Design Of A High-Power, High-Efficiency, Low-Distortion Direct From Digital Amplifier, Weston R. Earick

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For the process of converting low-power digital signals into their high-power analog counterparts, the functions of digital-to-analog conversion (at low power) and analog power amplification are separately implemented. This thesis proposes a new “STAC-DAC” circuit topology which directly realizes high-power analog output from low-power digital input signals. The ability to achieve a “direct from digital” high-power analog output in a single high-efficient, low-distortion design has significant potential in audio reproduction, and flexible signal generation applications. In this thesis, the “STAC-DAC” is described and its implementation via MATLAB and LTSpice is discussed. The results of simulations are used to prove the …