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A Sensor Network System For Monitoring Short-Term Construction Work Zones, Manohar Bathula Jan 2008

A Sensor Network System For Monitoring Short-Term Construction Work Zones, Manohar Bathula

ETD Archive

Safety hazards encountered near construction work zones are high, both in number and in the kind. There is a need to monitor traffic in such construction zones in order to improve driver and vehicle safetyIn the past traffic monitoring systems were built with high cost equipment such as inductive plates, video cameras etc. These solutions are too cost{prohibitive and invasive to be used in the large. Wireless sensor networks provide an opportunity space that can be used to address this problem. This thesis specifically targets temporary or short-term construction work zones. We present the design and implementation of a sensor …


A Wrapper-Based Approach To Sustained Time Synchronization In Wireless Sensor Networks, Dheeraj Reddy Bheemidi Jan 2008

A Wrapper-Based Approach To Sustained Time Synchronization In Wireless Sensor Networks, Dheeraj Reddy Bheemidi

ETD Archive

Time synchronization is an important service for wireless sensor network applications. Nodes in the network stay synchronized by exchanging periodic messages that carry local timestamps. Several algorithms have been proposed in the literature that are suited to different kinds of application scenarios. A common problem across these time synchronization algorithms is that the energy cost of message exchange is high. In fact, the cost of radio communication far outstrips the cost of performing local operations on the processor. If the message exchanges were stopped, nodes will fall out of sync, and may no longer be able to meet application requirements. …


Dspace Implementation Of A Generalized Method Of Harmonic Elimination For Pwm Boost Type Rectifier Under Unbalanced Operating Conditions, Ke Chen Jan 2008

Dspace Implementation Of A Generalized Method Of Harmonic Elimination For Pwm Boost Type Rectifier Under Unbalanced Operating Conditions, Ke Chen

ETD Archive

In this thesis, the implementation of a generalized method of harmonic elimination for the PWM boost type rectifier under severe fault conditions in the power system is presented. This method has been implemented by using DSPACE RT1104 digital control system. Control loop has been designed for real-time DC link voltage regulation. The simulation and experimental results verify the feasibility of the control scheme for input-output harmonic elimination. With the proposed method, unity power factor can be achieved as well as low-order harmonic elimination. High quality input and output waveforms of the three-phase PWM boost type rectifier are obtained under extremely …


Byzantine Fault Tolerance For Nondeterministic Applications, Bo Chen Jan 2008

Byzantine Fault Tolerance For Nondeterministic Applications, Bo Chen

ETD Archive

The growing reliance on online services accessible on the Internet demands highly reliable system that would not be interrupted when encountering faults. A number of Byzantine fault tolerance (BFT) algorithms have been developed to mask the most complicated type of faults - Byzantine faults such as software bugs,operator mistakes, and malicious attacks, which are usually the major cause of service interruptions. However, it is often difficult to apply these algorithms to practical applications because such applications often exhibit sophisticated non-deterministic behaviors that the existing BFT algorithms could not cope with. In this thesis, we propose a classification of common types …


A Scalable Clustered Camera System For Multiple Object Tracking, Senem Velipasalar, Jason Schlessman, Cheng-Yao Chen, Wayne H. Wolf, Jaswinder P. Singh Jan 2008

A Scalable Clustered Camera System For Multiple Object Tracking, Senem Velipasalar, Jason Schlessman, Cheng-Yao Chen, Wayne H. Wolf, Jaswinder P. Singh

Department of Electrical and Computer Engineering: Faculty Publications

Reliable and efficient tracking of objects by multiple cameras is an important and challenging problem, which finds wide-ranging application areas. Most existing systems assume that data from multiple cameras is processed on a single processing unit or by a centralized server. However, these approaches are neither scalable nor fault tolerant. We propose multicamera algorithms that operate on peer-to-peer computing systems. Peer-to-peer vision systems require codesign of image processing and distributed computing algorithms as well as sophisticated communication protocols, which should be carefully designed and verified to avoid deadlocks and other problems. This paper introduces the scalable clustered camera system, which …


Genomic Counter-Stress Changes Induced By The Relaxation Response, Jeffery A. Dusek, Hasan H. Otu, Ann L. Wohlhueter, Manoj Bhasin, Luiz F. Zerbini, Marie G. Joseph, Herbert Benson, Towia A. Libermann Jan 2008

Genomic Counter-Stress Changes Induced By The Relaxation Response, Jeffery A. Dusek, Hasan H. Otu, Ann L. Wohlhueter, Manoj Bhasin, Luiz F. Zerbini, Marie G. Joseph, Herbert Benson, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Background: Mind-body practices that elicit the relaxation response (RR) have been used worldwide for millennia to prevent and treat disease. The RR is characterized by decreased oxygen consumption, increased exhaled nitric oxide, and reduced psychological distress. It is believed to be the counterpart of the stress response that exhibits a distinct pattern of physiology and transcriptional profile. We hypothesized that RR elicitation results in characteristic gene expression changes that can be used to measure physiological responses elicited by the RR in an unbiased fashion.

Methods/Principal Findings: We assessed whole blood transcriptional profiles in 19 healthy, long-term practitioners of daily RR …


Proteomic Identification Of Interleukin-2 Therapy Response In Metastatic Renal Cell Cancer, Jon Jones, Hasan H. Otu, Franck Grall, Dimitrios Spentzos, Handan Can, Manuel Aivado, Arie S. Belldegrun, Allan J. Pantuck, Towia A. Libermann Jan 2008

Proteomic Identification Of Interleukin-2 Therapy Response In Metastatic Renal Cell Cancer, Jon Jones, Hasan H. Otu, Franck Grall, Dimitrios Spentzos, Handan Can, Manuel Aivado, Arie S. Belldegrun, Allan J. Pantuck, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Introduction—To detect a predictive protein profile that distinguishes between IL-2 therapy responders and non-responders among metastatic RCC patients we used surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI TOF-MS).

Materials and Methods—Protein extracts of 56 metastatic clear cell RCC patients obtained from radical nephrectomy specimens and prior to IL-2 therapy were applied to protein chip arrays of different chromatographic properties and analyzed using SELDI TOF-MS. A class prediction algorithm was applied to identify a subset of protein peaks whose expression values were associated with IL-2 response status. Multivariate analysis was performed to assess the association between the proteomic profile …


Grammar-Based Distance In Progressive Multiple Sequence Alignment, David Russell, Hasan H. Otu, Khalid Sayood Jan 2008

Grammar-Based Distance In Progressive Multiple Sequence Alignment, David Russell, Hasan H. Otu, Khalid Sayood

Department of Electrical and Computer Engineering: Faculty Publications

Background: We propose a multiple sequence alignment (MSA) algorithm and compare the alignment-quality and execution-time of the proposed algorithm with that of existing algorithms. The proposed progressive alignment algorithm uses a grammar-based distance metric to determine the order in which biological sequences are to be pairwise aligned. The progressive alignment occurs via pairwise aligning new sequences with an ensemble of the sequences previously aligned.
Results: The performance of the proposed algorithm is validated via comparison to popular progressive multiple alignment approaches, ClustalW and T-Coffee, and to the more recently developed algorithms MAFFT, MUSCLE, Kalign, and PSAlign using the BAliBASE 3.0 …


A Theoretical Framework For Quality-Aware Cross-Layer Optimized Wireless Multimedia Communications, Song Ci, Haohong Wang, Dalei Wu Jan 2008

A Theoretical Framework For Quality-Aware Cross-Layer Optimized Wireless Multimedia Communications, Song Ci, Haohong Wang, Dalei Wu

Department of Electrical and Computer Engineering: Faculty Publications

Although cross-layer has been thought as one of themost effective and efficient ways formultimedia communications over wireless networks and a plethora of research has been done in this area, there is still lacking of a rigorous mathematical model to gain indepth understanding of cross-layer design tradeoffs, spanning from application layer to physical layer. As a result, many existing cross-layer designs enhance the performance of certain layers at the price of either introducing side effects to the overall system performance or violating the syntax and semantics of the layered network architecture. Therefore, lacking of a rigorous theoretical study makes existing cross-layer …


Correlating Degradation Models And Image Quality Metrics, Darrin K. Reed, Elisa H. Barney Smith Jan 2008

Correlating Degradation Models And Image Quality Metrics, Darrin K. Reed, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

OCR often performs poorly on degraded documents. One approach to improving performance is to determine a good filter to improve the appearance of the document image before sending it to the OCR engine. Quality metrics have been measured in document images to determine what type of filtering would most likely improve the OCR response for that document image. In this paper those same quality metrics are measured for several word images degraded by known parameters in a document degradation model. The correlation between the degradation model parameters and the quality metrics is measured. High correlations do appear in many places …


Lightweight Objective Quality Of Voice Estimation Through Machine Learning, Daniel Riordan Jan 2008

Lightweight Objective Quality Of Voice Estimation Through Machine Learning, Daniel Riordan

Theses

Communication systems are undergoing constant and rapid innovation, both at the design stage and in the field. This in turn has led to an inereasing need for fast, efficient, portable and economic methods for the testing of these systems. For voice carrying communication systems the quality of the transmitted voice that the system produces is a large factor in the overall performance rating of the system. This measure is known as the ‘Quality of Voice’ (QoV) and can be evaluated either subjectively or objectively.

Speech quality is a complex subjective phenomenon that can be best quantified by subjective testing. A …


Development Of Laboratory Prototype Of A 12kva Digital Shunt Active Filter, N. G. Jayanti, Malabika Basu, Iurie Axente, Kevin Gaughan, Michael Conlon Jan 2008

Development Of Laboratory Prototype Of A 12kva Digital Shunt Active Filter, N. G. Jayanti, Malabika Basu, Iurie Axente, Kevin Gaughan, Michael Conlon

Conference papers

The paper reports the development of a laboratory prototype of a fully digital DSP controlled 12 kVA Shunt Active Filter (ShAF) capable of compensating for non-linear, unbalanced load and reactive power. A fully digital controller is implemented for the reference generation and the current control purposes. The delay problem in digital current controller is overcome by application of a fast DSP, a compact controller and proper flow of control steps in the DSP software. A Phase Locked Loop (PLL)-less software grid synchronization method has been proposed for the effective operation of the ShAF under the grid frequency variation. The source …


Ultra-Wide Band In Communications: Performance Analysis And Enhancements, Burak Berksoy Jan 2008

Ultra-Wide Band In Communications: Performance Analysis And Enhancements, Burak Berksoy

Electronic Theses and Dissertations

Over the last ten years, Ultra-Wide Band (UWB) technology has attracted tremendous research attention. Frequency allocation of 3.1-10.6 GHz for UWB application by FCC made it apparent that UWB will be the technology for future wireless high speed communication applications. With the promise of high data rates (high channel capacity), UWB also offers advantages such as communication security, high multi-path resolution, good penetration capability, ability to coexist with other communication schemes in the same band, and finally, circuit simplicity. The theoretical advantages of UWB has made it a great candidate for short distance communications, however, UWB communications have many challenges, …


Bi-Directional Dcm Dc-To-Dc Converter For Hybrid Electric Vehicles, Michael Pepper Jan 2008

Bi-Directional Dcm Dc-To-Dc Converter For Hybrid Electric Vehicles, Michael Pepper

Electronic Theses and Dissertations

With the recent revival of the hybrid vehicle much advancement in power management has been made. The most popular hybrid vehicle, the hybrid electric vehicle, has many topologies developed to realize this hybrid vehicle. From these topologies, as sub set was created to define a particular group of vehicles where the converter discussed in this thesis has the most advantage. This sub set is defined by two electric sources of power coupled together at a common bus. This set up presents many unique operating conditions which can be handled seamlessly by the DC-to-DC converter when designed properly. The DC-to-DC converter …


Effects Of Source Water Blending Following Treatment With Sodium Silicate As A Corrosion Inhibitor On Metal Release Within A Wat, Phillip Lintereur Jan 2008

Effects Of Source Water Blending Following Treatment With Sodium Silicate As A Corrosion Inhibitor On Metal Release Within A Wat, Phillip Lintereur

Electronic Theses and Dissertations

A study was conducted to investigate and quantify the effects of corrosion inhibitors on metal release within a pilot distribution system while varying the source water. The pilot distribution system consisted of pre-existing facilities from Taylor et al (2005). Iron, copper, and lead release data were collected during four separate phases of operation. Each phase was characterized by the particular blend ratios used during the study. A blended source water represented a water that had been derived from a consistent proportion of three different source waters. These source waters included (1) surface water treated through enhanced coagulation/sedimentation/filtration, (2) conventionally treated …


Modeling And Analysis Of Power Mosfets For High Frequency Dc-Dc Converters, Yali Xiong Jan 2008

Modeling And Analysis Of Power Mosfets For High Frequency Dc-Dc Converters, Yali Xiong

Electronic Theses and Dissertations

Evolutions in integrated circuit technology require the use of a high-frequency synchronous buck converter in order to achieve low cost, low profile, fast transient response and high power density. However, high frequency operation leads to increased power MOSFET switching losses. Optimization of the MOSFETs plays an important role in improving converter performance. This dissertation focuses on revealing the power loss mechanism of power MOSFETs and the relationship between power MOSFET structure and its power loss. The analytical device model, combined with circuit modeling, cannot reveal the relationship between device structure and its power loss due to the highly non-linear characteristics …


Digital Signal Processing Techniques For Coherent Optical Communication, Gilad Goldfarb Jan 2008

Digital Signal Processing Techniques For Coherent Optical Communication, Gilad Goldfarb

Electronic Theses and Dissertations

Coherent detection with subsequent digital signal processing (DSP) is developed, analyzed theoretically and numerically and experimentally demonstrated in various fiber-optic transmission scenarios. The use of DSP in conjunction with coherent detection unleashes the benefits of coherent detection which rely on the preservation of full information of the incoming field. These benefits include high receiver sensitivity, the ability to achieve high spectral-efficiency and the use of advanced modulation formats. With the immense advancements in DSP speeds, many of the problems hindering the use of coherent detection in optical transmission systems have been eliminated. Most notably, DSP alleviates the need for hardware …


Meshfree Approximation Methods For Free-Form Optical Surfaces With Applications To Head-Worn Displays, Ozan Cakmakci Jan 2008

Meshfree Approximation Methods For Free-Form Optical Surfaces With Applications To Head-Worn Displays, Ozan Cakmakci

Electronic Theses and Dissertations

Compact and lightweight optical designs achieving acceptable image quality, field of view, eye clearance, eyebox size, operating across the visible spectrum, are the key to the success of next generation head-worn displays. The first part of this thesis reports on the design, fabrication, and analysis of off-axis magnifier designs. The first design is catadioptric and consists of two elements. The lens utilizes a diffractive optical element and the mirror has a free-form surface described with an x-y polynomial. A comparison of color correction between doublets and single layer diffractive optical elements in an eyepiece as a function of eye clearance …


Energy Efficient Wireless Sensor Network Protocols For Monitoring And Prognostics Of Large Scale Systems, James W. Fonda Jan 2008

Energy Efficient Wireless Sensor Network Protocols For Monitoring And Prognostics Of Large Scale Systems, James W. Fonda

Doctoral Dissertations

"In this work, energy-efficient protocols for wireless sensor networks (WSN) with applications to prognostics are investigated. Both analytical methods and verification are shown for the proposed methods via either hardware experiments or simulation. This work is presented in five papers. Energy-efficiency methods for WSN include distributed algorithms for i) optimal routing, ii) adaptive scheduling, iii) adaptive transmission power and data-rate control"--Abstract, page iv.


System And Ic Level Analysis Of Electrostatic Discharge (Esd) And Electrical Fast Transient (Eft) Immunity And Associated Coupling Mechanisms, Jayong Koo Jan 2008

System And Ic Level Analysis Of Electrostatic Discharge (Esd) And Electrical Fast Transient (Eft) Immunity And Associated Coupling Mechanisms, Jayong Koo

Doctoral Dissertations

"The exposure of electronic circuits to lightning, electrostatic discharge (ESD), electrical fast transients (EFT) or sine wave signals can reveal RF immunity problems. Typical problems include temporary malfunctions or permanent damage of integrated circuits (ICs). In an effort to reproduce those disturbances, a series of electromagnetic compatibility standards has been developed. However, a complete understanding of the root cause of the immunity problems has yet to be established. This dissertation discusses immunity problems in three papers, starting at the system level, via the coupling path into the IC"--Abstract, page iv.


Color Multiplexed Single Pattern Sli, Neelima Mandava Jan 2008

Color Multiplexed Single Pattern Sli, Neelima Mandava

University of Kentucky Master's Theses

Structured light pattern projection techniques are well known methods of accurately capturing 3-Dimensional information of the target surface. Traditional structured light methods require several different patterns to recover the depth, without ambiguity or albedo sensitivity, and are corrupted by object movement during the projection/capture process. This thesis work presents and discusses a color multiplexed structured light technique for recovering object shape from a single image thus being insensitive to object motion.

This method uses single pattern whose RGB channels are each encoded with a unique subpattern. The pattern is projected on to the target and the reflected image is captured …


Motion Correction Structured Light Using Pattern Interleaving Technique, Raja Kalyan Ram Cavaturu Jan 2008

Motion Correction Structured Light Using Pattern Interleaving Technique, Raja Kalyan Ram Cavaturu

University of Kentucky Master's Theses

Phase Measuring Profilometry (PMP) is the most robust scanning technique for static 3D data acquisition. To make this technique robust to the target objects which are in motion during the scan interval a novel algorithm called ‘Pattern Interleaving’ is used to get a high density single scan image and making Phase Measuring Profilometry insensitive to ‘z’ motion and prevent motion banding which is predominant in 3D reconstruction when the object is in motion during the scan time


A Low Polarization Sensitivity All-Fiber Wavelength Measurement System, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Qian Wang, Pengfei Wang Jan 2008

A Low Polarization Sensitivity All-Fiber Wavelength Measurement System, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Qian Wang, Pengfei Wang

Articles

A low polarization-sensitive all-fiber wavelength measurement system using a twisted macro-bend fiber edge filter together with polarization-insensitive (PI) 3-dB coupler is presented. Eliminating the polarization-dependent loss (PDL) is essential when macro-bending single-mode fiber is utilized as an edge filter. A new bending configuration to eliminate the PDL of a fiber edge filter is proposed in this letter by twisting the fiber by 90deg between two bending sections with equal length. The PDL of this configuration retains a low value even while the bending length is increased to achieve a steeper response for the edge filter. This configuration together with a …


Structural Segmentation Using Set Accented Tones, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle Jan 2008

Structural Segmentation Using Set Accented Tones, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle

Conference papers

An approach which efficiently segments Irish Traditional Music into its constituent structural segments is presented. The complexity of the segmentation process is greatly increased due to melodic variation existent within this music type. In order to deal with these variations, a novel method using ‘set accented tones’ is introduced. The premise is that these tones are less susceptible to variation than all other tones. Thus, the location of the accented tones is estimated and pitch information is extracted at these specific locations. Following this, a vector containing the pitch values is used to extract similar patterns using heuristics specific to …


Pitch Tracking And Voiced/Unvoiced Detection In Noisy Environment Using Optimat Sequence Estimation, Moshe Wasserblat, Mikel Gainza, David Dorran, Yuval Domb Jan 2008

Pitch Tracking And Voiced/Unvoiced Detection In Noisy Environment Using Optimat Sequence Estimation, Moshe Wasserblat, Mikel Gainza, David Dorran, Yuval Domb

Conference papers

This paper addresses the problem of pitch tracking and voiced/unvoiced detection in noisy speech environments. An algorithm is presented which uses a number of variable thresholds to track pitch contour with minimal error. This is achieved by modeling the pitch tracking problem in such a way that allows the use of optimal estimation methods, such MLSE. The performance of the algorithm is evaluated using the Keele pitch detection database with realistic background noise. Results show best performance in comparison to other state of the art pitch detector and successful pitch tracking is possible in low signal to noise conditions.


Role Of Artificial Intelligence In The Reliability Evaluation Of Electric Power Systems, Chanan Singh, Lingfeng Wang Jan 2008

Role Of Artificial Intelligence In The Reliability Evaluation Of Electric Power Systems, Chanan Singh, Lingfeng Wang

Turkish Journal of Electrical Engineering and Computer Sciences

Every reliability analysis effort, in some way, involves searching the state space of the system for those states that represent the events of interest, typically failure of the system or a given node to meet the demand. This essentially translates into a search procedure to efficiently identify states to be examined and then using a mechanism to evaluate these states. Traditionally, reliability analysis methods are based either on an implicit or explicit enumeration process or Monte Carlo sampling. More recently, methods based on artificial intelligence have been investigated both as an alternative to Monte Carlo for the search process as …


Low Power Energy Harvesting And Storage Techniques From Ambient Human Powered Energy Sources, Faruk Yildiz Jan 2008

Low Power Energy Harvesting And Storage Techniques From Ambient Human Powered Energy Sources, Faruk Yildiz

Dissertations and Theses @ UNI

Conventional electrochemical batteries power most of the portable and wireless electronic devices that are operated by electric power. In the past few years, electrochemical batteries and energy storage devices have improved significantly. However, this progress has not been able to keep up with the development of microprocessors, memory storage, and sensors of electronic applications. Battery weight, lifespan and reliability often limit the abilities and the range of such applications of battery powered devices. These conventional devices were designed to be powered with batteries as required, but did not allow scavenging of ambient energy as a power source. In contrast, development …


Socially Rational Models For Autonomous Agents, Wynn C. Stirling, James K. Archibald, Matthew S. Nokleby Jan 2008

Socially Rational Models For Autonomous Agents, Wynn C. Stirling, James K. Archibald, Matthew S. Nokleby

Faculty Publications

Autonomous multi-agent systems that are to coordinate must be designed according to models that accommodate such complex social behavior as compromise, negotiation, and altruism. In contrast to individually rational models, where each agent seeks to maximize its own welfare without regard for others, socially rational agents have interests beyond themselves. Such models require a new type of utility function a social utility to ensure three desirable properties: (a) conditional preferences agents may adjust their preferences to account for the preferences of others; (b) endogeny group preferences are determined internally by interactions between individual agents; (c) framing invariance reformulations of the …


The Copula: A Tool For Simulating Speckle Dynamics, Donald D. Duncan, Sean J. Kirkpatrick Jan 2008

The Copula: A Tool For Simulating Speckle Dynamics, Donald D. Duncan, Sean J. Kirkpatrick

Electrical and Computer Engineering Faculty Publications and Presentations

Use of a copula for generating a sequence of correlated speckle patterns is introduced. The chief characteristic of this algorithm is that it generates a continuous speckle sequence with a specified evolution of the correlation and does so with just two arrays of random numbers. Thus, physically realistic temporally varying speckle patterns with proper first- and second-order statistics are easily realized. We illustrate use of the algorithm for generating sequences with prescribed Gaussian, exponential, and equal-interval correlations and demonstrate how correlation times can be specified independently. This approach to generating sequences of random realizations with prescribed correlations should prove useful …


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. …