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Wavelet Based Array Comparative Genomic Hybridization And Mass Spectrometry Data Analysis, Nha Nguyen Jan 2010

Wavelet Based Array Comparative Genomic Hybridization And Mass Spectrometry Data Analysis, Nha Nguyen

Electrical Engineering Dissertations - Archive

As a highly efficient technique, array-based comparative genomic hybridization (aCGH) methods allow the simultaneous measurement of genomic DNA copy number at hundreds or thousands of loci and the reliable detection of local one-copy-level variations. The identification of these DNA copy number changes provides insights to facilitate both the basic understanding of cancer and its diagnosis. In order to effectively analyze aCGH data, various techniques have been proposed to help researchers smooth the DNA copy number data and subsequently to quantify the alterations. In this thesis, many wavelet based methods are proposed to smooth and segment the aCGH data that is …

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Mimic: An Active Covert Channel That Evades Regularity-Based Detection, Kush Kothari Jan 2010

Mimic: An Active Covert Channel That Evades Regularity-Based Detection, Kush Kothari

Computer Science and Engineering Theses - Archive

A covert timing channel is a hidden communication channel based on network timing that an attacker can use to sneak secrets out of a secure system. Active covert channels, in which the attacker uses a program to automatically generate innocuous traffic to use as a medium for embedding the covert channel, are especially problematic, as they allow the attacker to output large amounts of secret data. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This technique can reliably detect known covert timing channels by using a combination of entropy (EN) and conditional entropy (CE) to …

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Target Tracking With Lucas-Kanade Optical Flow And Particle Filters Through Affine Transforms And Occlusion, Justin Graham Jan 2010

Target Tracking With Lucas-Kanade Optical Flow And Particle Filters Through Affine Transforms And Occlusion, Justin Graham

Computer Science and Engineering Theses - Archive

This paper investigates a hybrid approach derived from Lucas-Kanade optical flow tracking and particle filters that is capable of tracking objects through occlusion and affine transformations. This approach is inspired by aircraft sensor pod infrared and electro-optical tracking applications. For aircraft based sensors, it is important that a tracking system be able to track through rotations as the aircraft orbits a targeting area. It is also of use to handle cases where the target may be momentarily occluded due to other vehicles or obstacles in the area. The main focus of this investigation is to find a technique that performs …

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A Framework For Real-Time Fault Detection And Response In Multi-Agent Teams, Matthew B. Middleton Jan 2010

A Framework For Real-Time Fault Detection And Response In Multi-Agent Teams, Matthew B. Middleton

Computer Science and Engineering Theses - Archive

This thesis details the creation of a fault detection and response framework that can be applied to mobile multi-agent teams. This framework unites existing concepts of conditioned based maintenance and real-time machine diagnostics with a high-level matrix based discrete event command and control system that can respond to detected mechanical faults in agents in real-time. This allows for automatic corrective actions to be taken when an agent experiences failure if redundant resources are available to replace the failed unit or for the mission planner to be notified that the mission is no longer achievable given the operating conditions of the …

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Real Time Hardware And Software Systems For Micro Air Vehicle Flight Control Testing, Christopher Dale Mcmurrough Jan 2010

Real Time Hardware And Software Systems For Micro Air Vehicle Flight Control Testing, Christopher Dale Mcmurrough

Computer Science and Engineering Theses - Archive

The trend of increasing capabilities of micro scale electrical, mechanical, and computing systems is opening up the possibilities of new unmanned vehicle platforms. Both unmanned aerial and ground vehicles have traditionally been created from large conventional platforms such as automobiles, rotorcraft, and fixed wing aircraft. These conventional chassis designs are durable and proven, but the benefits of automating these types of platforms are limited by their inherent human-centric design. Many real-world applications would benefit greatly from vehicle classes designed with unconventional means such as biologically inspired locomotion. Micro air vehicles are a class of vehicles that have recently began moving …

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Fast Jamming Detection In Wireless Sensor Networks, Kartik Siddhabathula Jan 2010

Fast Jamming Detection In Wireless Sensor Networks, Kartik Siddhabathula

Computer Science and Engineering Theses - Archive

Non-dedicated medium of communication for Wireless Sensor Networks (WSN) makes them vulnerable to jamming attack where an adversary injects strong signal or noises to interfere with the transmission and thus block the channel. In applications such as border security, people are particularly interested in the areas where the channel is currently jammed. It is therefore crucial to be able to detect the jamming attacks as fast as possible. Existing studies have shown that the most effective indicator of jamming attacks is the packet delivery ratio (PDR). However, current PDR-based schemes use end-to-end packet delivery ratio, which requires one to observe …

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Fast And Energy-Efficient Technique For Jammed Region Mapping In Wireless Sensor Networks, Nabila Rahman Jan 2010

Fast And Energy-Efficient Technique For Jammed Region Mapping In Wireless Sensor Networks, Nabila Rahman

Computer Science and Engineering Theses - Archive

Wireless sensor networks (WSNs) have great practical importance for surveillance systems to perform monitoring by acquiring and sending information about intrusions into a secured area. Very little human intervention is required for WSNs, which is one of the most desirable features of them and thus making them a cheaper and safer alternative for securing large area such as international borders. Jamming attacks in WSNs can be applied to disrupt communications among the sensor nodes in the network by barring the reception of wireless signals of the sensor nodes' transceivers. Since it is difficult to prevent jamming attacks, detection and mapping …

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A Tutorial On Functionality Of Wimax And It's Performace Evaluation, Amay Dhirendra Umradia Jan 2010

A Tutorial On Functionality Of Wimax And It's Performace Evaluation, Amay Dhirendra Umradia

Electrical Engineering Theses - Archive

Recently, there have been tremendous developments on wireless communication technology which have predicted to replace the wirelined system and provide incredible bandwidth to the consumers. The IEEE standard for this technology is known as 802.16e (Mobile WiMAX) which was officially published in the year 2006. WiMAX would provide broadband access to rural and developing countries where the option of DSL, cable and Wi-Fi is unavailable. This Thesis provides a tutorial overview of 802.16. The information for this article is gathered from The Institute of Electrical and Electronics Engineers (IEEE) website, the WiMAX forum website and other resources on the internet. …

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A Planar Cavity Backed Slot Antenna Array For Ultra-Wideband Monopulse Radars, Vinay Magadi Vikram Jan 2010

A Planar Cavity Backed Slot Antenna Array For Ultra-Wideband Monopulse Radars, Vinay Magadi Vikram

Electrical Engineering Theses - Archive

In this thesis, a wideband cavity backed slot antenna is designed for automotive-borne monopulse radar applications. A rectangular slot is used to realize broad bandwidth; the slot is backed by a cavity and vertical walls of the cavity are implemented by discrete vias; and the slot is fed by an inverted microstrip line. The antenna in this letter is compact, robust, fully planar, and easy to integrate. A two-element array is fabricated and tested. Measured input impedance is matched to 50-ohm within band [2.61 GHz, 3.44 GHz] (27.5% bandwidth); and monopulse beam-scanning is successfully demonstrated.

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Dispersion Engineering With Leaky-Mode Resonance Structures, Xin Wang Jan 2010

Dispersion Engineering With Leaky-Mode Resonance Structures, Xin Wang

Electrical Engineering Theses - Archive

In the thesis, a numerical method for the analysis of optical pulses propagation through leaky-mode/guided-mode resonance (GMR) structures is implemented by integrating a Fourier decomposition technique and the rigorous coupled-wave analysis (RCWA) method. Dispersion properties of several GMR structures such as single-grating-layer GMR filters, coupled GMR filters, and cascaded GMR filters are studied and their interaction with optical pulses investigated. For device applications, a high-Q transmission filter is formed by coupling GMR reflection filters which can withstand typical attenuation in silicon. Wavelength division multiplexing (WDM) filters are proposed by cascading a number of GMR transmission filters. Generally, a N channel …

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Pediatric Nurses' Journeys To Relieve Children's Post-Operative Pain, Renee C.B. Manworren Jan 2010

Pediatric Nurses' Journeys To Relieve Children's Post-Operative Pain, Renee C.B. Manworren

Nursing Dissertations - Archive

This study sought to bridge the gap of nurses' knowledge of pain management and translation into clinical practice by describing pediatric nurses' negotiation of the bureaucracy of caring. The purpose of this study was to describe factors that influenced pediatric nurses' actions to relieve children's acute post-operative pain on a pediatric post-surgical care unit. The bureaucracy of caring provided the theoretical framework. A qualitative descriptive study of human factors engineering and ethnography was used to quantify the impact of influential variables on time from assessment to intervention. Few knowledge deficits were identified; but nurses' general knowledge and attitudes regarding pain …

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Multiplexing Of Avs China Video With Aac Audio Bit Streams & De-Multiplexing With Lip Synchronization During Playback, Swaminathan Sridhar Jan 2010

Multiplexing Of Avs China Video With Aac Audio Bit Streams & De-Multiplexing With Lip Synchronization During Playback, Swaminathan Sridhar

Electrical Engineering Theses - Archive

AVS China is the latest digital video coding standard released by the AVS working group of China which has been proven superior to the other video coding standards such as H.261, MPEG-1 and MPEG-2 in terms of coding efficiency and reduced complexity. AVS standard employs the latest video coding tools which mainly target standard definition (SD) and high definition (HD) video compression and aim to achieve a similar coding efficiency of H.264/AVC but with reduced complexity. AVS video standard was developed in order to target broadcast and storage media applications such as digital video television, digital video disk (DVD and …

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Analysis And Improvement Of Multiple Optimal Learning Factors For Feed-Forward Networks, Praveen Jesudhas Jan 2010

Analysis And Improvement Of Multiple Optimal Learning Factors For Feed-Forward Networks, Praveen Jesudhas

Electrical Engineering Theses - Archive

The effects of transforming the net function vector in the Multilayer Perceptron (MLP) are analyzed. The use of optimal diagonal transformation matrices on the net function vector is proved to be equivalent to training the MLP using multiple optimal learning factors (MOLF). A method for linearly compressing large ill-conditioned MOLF Hessian matrices into smaller well-conditioned ones is developed. This compression approach is shown to be equivalent to using several hidden units per learning factor. The technique is extended to large networks. In simulations, the proposed algorithm performs almost as well as the Levenberg Marquardt (LM) algorithm with the computational complexity …

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Event Recognition From Ambient Assistive Living Technologies, Eric William Becker Jan 2010

Event Recognition From Ambient Assistive Living Technologies, Eric William Becker

Computer Science and Engineering Dissertations - Archive

As the population ages and technology advances, a need exists for creating ambient intelligent systems to be placed within the home environment. Attitudes towards technology have been changing, and home monitoring is now considered a less expensive and desirable alternative. Ideally, such systems should be small, wireless, and take the minimum of effort and cost to install and place within the home. In order to detect human activity in an assistive environment, key questions about the construction and operation of the technology and methods needed to detect that activity. To that end, a computational framework has been created inside an …

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Advanced Software Testing Techniques Based On Combinatorial Design, Wenhua Wang Jan 2010

Advanced Software Testing Techniques Based On Combinatorial Design, Wenhua Wang

Computer Science and Engineering Dissertations - Archive

Combinatorial testing refers to a testing strategy that applies the principles of combinatorial design to the domain of software test generation. Given a system with k parameters, combinatorial testing requires all the combinations involving t out of k parameters be covered at least once, where t is typically much smaller than k. The key insight behind combinatorial testing is that while the behavior of a system may be affected by many parameters, most faults are caused by interactions involving only a small number of parameters. Empirical studies have shown that combinatorial testing can dramatically reduce the number of tests while …

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Information-Driven Data Gathering In Wireless Sensor Networks, Jing Wang Jan 2010

Information-Driven Data Gathering In Wireless Sensor Networks, Jing Wang

Computer Science and Engineering Dissertations - Archive

Since the advance of wireless technology enables the mass production of low-cost, small-sized sensor nodes, sensor nodes can be densely deployed in an area for high tolerance to node failure or to achieve better coverage statistically. The redundancy of sensor nodes results in the temporal and spatial correlation of sensory data, which motivates the information-driven data gathering approaches for wireless sensor networks (WSNs).Since existing approaches target at the sensory data that are already highly correlated with each other, little attention has been paid to the idea of changing the sampling schedules of the sensor nodes to reduce the correlation among …

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Combating Dos Attacks In Wireless Networks Using Lightweight Key Mangement Schemes, Qi Dong Jan 2010

Combating Dos Attacks In Wireless Networks Using Lightweight Key Mangement Schemes, Qi Dong

Computer Science and Engineering Dissertations - Archive

The unique features of wireless networks lead to many attractive applications in both military and civilian operations. Wireles networking devices usually use batteries as power supply, which requires all the operations to be as efficient as possible. Since the resources such as the battery energy and wireless communication channels are critical in wireless networks, the attacker my try to disable the system operation by launching denial of service (DoS) attacks. Specifically, the attacker prevents the system from working by using up or blocking the limited resources.This dissertation includes three studies on security mechanisms to combat DoS attacks using lightweight key …

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Development Of Magnetic-Based Core-Shell Nanoparticles For Drug Delivery Applications In Melanoma Skin Cancer, Zarna A. Bhavsar Jan 2010

Development Of Magnetic-Based Core-Shell Nanoparticles For Drug Delivery Applications In Melanoma Skin Cancer, Zarna A. Bhavsar

Bioengineering Theses - Archive

Melanoma skin cancer is the most dangerous form of skin cancer and the major cause of deaths related to skin cancer worldwide. Conventional chemotherapeutic treatment is not very effective and faces many problems such as low response rate, development of multidrug resistance, and severe side effects. In order to address these limitations and improve melanoma treatment efficacy, development of a multifunctional nanoparticulate drug delivery system is desired. Thus, we aimed towards the development of magnetic-based core-shell nanoparticles (MBCS NPs) for dual drug release and dual targeting of melanoma tumors. The synthesized nanoparticles were composed of Poly (Lactic-co-glycolic acid) (PLGA) particle …

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A Novel Injectable Porous Hydrogel Composite Scaffold For Bone Tissue Engineering, Parvathi Nair Jan 2010

A Novel Injectable Porous Hydrogel Composite Scaffold For Bone Tissue Engineering, Parvathi Nair

Bioengineering Theses - Archive

Over the past decade there has been an increasing use of bone grafts for orthopedic applications. With the aging US population, the need for suitable bone grafts substitutes has also increased. The aim of this study was to develop a novel in situ crosslinkable hydrogel composite for tissue-engineering critical-sized bone defects. This system consists of a newly developed water-soluble biodegradable hydrogel Poly ((ethylene glycol) maleate citrate) (PEGMC) and hydroxyapatite (HA). The PEGMC/HA system is completely injectable and can be crosslinked in situ into crosslinked PEGMC/HA (CPEGMC/HA) hydrogel composite with or without poly (ethylene glycol) diacrylate (PEGDA) as a crosslinker. The …

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Microfluidic Systems For Studying Cell Motility, Srikanth Vasudevan Jan 2010

Microfluidic Systems For Studying Cell Motility, Srikanth Vasudevan

Bioengineering Theses - Archive

It is very imperative to develop new in vitro platforms that can help in studying the complex interactions that occur between cell-Extracellular Matrix proteins and also during the process of cell migration in vivo. Such tools would facilitate in better understanding of the mechanisms that are employed by the cells during growth and migration. There are two devices that are presented in this study; 1) Multi-biomolecule coated lane device for unbiased cell preferential migration and 2) Novel Microchannel device for real time monitoring of tumor cell migration.The Multi-biomolecule coated lane device is a basic in vitro platform that helps in …

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Electrowetting Of Ionic Liquids And Development Of An Electrowetting Based Tunable Rc Filter And Its Uses As An Analytical Detector, Yasith Sameera Nanayakkara Jan 2010

Electrowetting Of Ionic Liquids And Development Of An Electrowetting Based Tunable Rc Filter And Its Uses As An Analytical Detector, Yasith Sameera Nanayakkara

Chemistry & Biochemistry Dissertations - Archive

Wettability control of a liquid drop by an external electric field or "electrowet- ting" recently was the subject of special interest among researchers due to its util- ity for a variety of applications. Some of these include "electrowetting on dielectric (EWOD)" based digital microfluidic lab-on-a-chip devices, EWOD lenses and EWOD displays. In these EWOD based devices, water or aqueous electrolytes are used as the liquid medium. However, the use of water or aqueous electrolytes has several limitations and may reduce the efficiency as well as accuracy of these devices. Low thermal stability, evaporation, fouling and fixed phys- iochemical properties are …

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Pseudo-Probabilistic User Equilibrium Assignment In Travel Corridor Networks Containing Managed Facilities, Alireza Khaleghi-Soroush Jan 2010

Pseudo-Probabilistic User Equilibrium Assignment In Travel Corridor Networks Containing Managed Facilities, Alireza Khaleghi-Soroush

Civil Engineering Dissertations - Archive

Throughout the years, transportation organizations and agencies have been unable to keep up with increasing demand for roadway facilities. Similarly, traditional public-sector funding such as motor fuel taxes is falling short in meeting the growing demand for new transportation infrastructure. With deficit financing and congestion problems common to many highways throughout the United States, DOTs are turning to tolling the roadway facilities as a means of financing transportation improvements for inter-urban and urban facilities.In turn, in order for managed facilities such as toll roads or managed lanes to be attractive and viable for the potential investors, the facilities must be …

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Leading The James: The Morphological Changes Of The Missouri River And The Subservient James River, April Deann Moreno Jan 2010

Leading The James: The Morphological Changes Of The Missouri River And The Subservient James River, April Deann Moreno

Earth & Environmental Sciences Theses - Archive

The James River flows into the Missouri River east of Yankton, SD. The degree to which the morphological changes of the Missouri River had an impact on the course of the James River is debatable. After mapping the Mission Hill and Menominee quadrangles, surficial maps have been made showing the preserved allounits of the area. Hand augers were used to ground-truth surface features located through the use of aerial photographs, topographic maps, and to confirm features on the surficial maps made. OSL samples were taken from both quadrangles and also from Meckling and Saint Helena; the latter two were mapped …

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Environmentally-Conscious Supply Chain Design In Support Of Food Security, Caroline C. Krejci, Benita M. Beamon Jan 2010

Environmentally-Conscious Supply Chain Design In Support Of Food Security, Caroline C. Krejci, Benita M. Beamon

Industrial, Manufacturing, and Systems Engineering Faculty Publications - Archive

This paper seeks to design food supply chain structures that can provide food security for every person in the world while supporting long-term environmental sustainability. In particular, we provide alternatives to the current food supply chain structure and analyze their potential for providing food security, in terms of productive capacity and long-term environmental sustainability. Given the current world population and expected continued growth, our analysis suggests that environmentally-sustainable food supply chains would be most effectively supported by local and organic agriculture, while maintaining a parallel industrial agricultural system. This hybrid system would adopt environmentally-sustainable principles whenever possible, seeking to increase …

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Reinforcement Learning Based Strategies For Adaptive Wireless Sensor Network Management, Kunalbhai Shah Jan 2010

Reinforcement Learning Based Strategies For Adaptive Wireless Sensor Network Management, Kunalbhai Shah

Computer Science and Engineering Dissertations - Archive

In wireless sensor networks (WSN), resource-constrained nodes are expected to operate in highly dynamic and often unattended environments. WSN applications need to cope with such dynamicity and uncertainty intrinsic in sensor networks, while simultaneously trying to achieve efficient resource utilization. A middleware framework with support for autonomous, adaptive and distributed sensor management, can simplify development of such WSN applications. We present a reinforcement learning based WSN middleware framework to enable autonomous and adaptive applications with support for efficient resource management. The uniqueness of our framework lies in using a bottom-up approach where each sensor node is responsible for its resource …

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Development Of An Optical Fiber-Based Corrosion Detection Sensor Based On Laser Light Reflection, Manjunatha Shenoy Jan 2010

Development Of An Optical Fiber-Based Corrosion Detection Sensor Based On Laser Light Reflection, Manjunatha Shenoy

Mechanical and Aerospace Engineering Theses - Archive

Corrosion plays a detrimental effect on the structural integrity of many engineering structures. It can compromise the safe operation of these structures by forming corrosion pits that deteriorates the structural surfaces and causes stress concentrations. Therefore, it is critical that corrosions are detected before structural integrity is compromised and repair becomes economically prohibitive. However, corrosions usually occur at intricate places that are hard to inspect visually. Manual inspection of the structures for corrosions requires dismantling the structures, which incurs high maintenance costs and could potentially cause damage to the components. One approach to reduce this cost is to detect and …

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An Integration Of A Modern Flight Control System Design Technique Into A Conceptual Design Stability And Controls Tool, Aeromech, Amen Omoragbon Jan 2010

An Integration Of A Modern Flight Control System Design Technique Into A Conceptual Design Stability And Controls Tool, Aeromech, Amen Omoragbon

Mechanical and Aerospace Engineering Theses - Archive

The aircraft conceptual design (CD) phase is the most abstract, thus challenging phase of the entire aircraft design process. It is the responsibility of the CD engineer to identify and then to explore various aircraft concepts with the goal of arriving at the most promising concept for further evaluation. During this early design phase, the discipline stability and control tends to be underrepresented due to the lack of non-linear aerodynamic and inertia data. The methodology and software AeroMech is a vehicle configuration independent aircraft conceptual design stability and control tool, developed to help the conceptual designer to address stability and …

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Alternative Matching Schemes For Automatic Fingerprint Identification Systems, Michael Jason Futer Jan 2010

Alternative Matching Schemes For Automatic Fingerprint Identification Systems, Michael Jason Futer

Electrical Engineering Theses - Archive

Biometrics is a recognition technology that uses the unique behavioral and physiological traits of the human body as identifiers. The fingerprint is one of the oldest and most widely used forms of biometric identifiers. In this thesis, an automatic fingerprint identification system designed by a previous Electrical Engineering graduate student at The University of Texas at Arlington is upgraded with the purpose of improving matching accuracy. A review of the baseline automatic fingerprint identification system is provided as a reference point for improvements in the system. Then, improvements to the image enhancement stage of the baseline system are discussed. They …

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A Ph Sensor Based On A Flexible Substrate, Wen-Ding Huang Jan 2010

A Ph Sensor Based On A Flexible Substrate, Wen-Ding Huang

Electrical Engineering Dissertations - Archive

pH sensor is an essential component used in many chemical, food, and bio-material industries. Conventional glass electrodes have been used to construct pH sensors, however, have some disadvantages. Glass electrodes are easily affected by alkaline or HF solution, they require a high input impedance pH meter, they often exhibit a sluggish response. In some specific applications, it is also difficult to use glass electrodes for in vivo biomedical or food monitoring applications due to the difficulty of size miniaturization, planarization and polymerization based on current manufacturing technologies. In this work, we have demonstrated a novel flexible pH sensor based on …

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Distribution Network Contingency Analysis And Contingency Detection With The Consideration Of Load Models, Qiaohui Hu Jan 2010

Distribution Network Contingency Analysis And Contingency Detection With The Consideration Of Load Models, Qiaohui Hu

Electrical Engineering Dissertations - Archive

The electric utility market environment has changed quite radically during recent years due to the process of deregulation. This has changed the asset management towards a capital controlled business where owners are trying to maximize their profits with cost optimization. To keep up with the increase demands on high reliability and high quality delivery systems, many utilities endeavor to rationalize their system operations with more intelligent control schemes and facilities. A lot of issues under uncertainty such as load growth, quality of supply and environmental impact affect the reliability of the distribution system. Power outage is the most serious challenge …

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