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Electrical and Electronics Commons™

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2011

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Articles 121 - 150 of 207

Full-Text Articles in Electrical and Electronics

Led Spotlight, Eric Toussaint Mar 2011

Led Spotlight, Eric Toussaint

Electrical Engineering

This report details the development and construction of an LED spotlight useable in a theatrical or architectural setting.  In depth background information, initial design concepts, lighting instrument specifications, assembly, testing, and conclusions from results are highlighted in this document.  Project goals include efforts to support more energy efficient lighting in the arts and general lighting applications and a decrease in overall costs for energy used in all dramatic and architectural lighting applications.

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Electric Guitar Amplifier With Digital Effects, Shawn Garrett Feb 2011

Electric Guitar Amplifier With Digital Effects, Shawn Garrett

Computer Engineering

During the course of this project, the research and development of an electric guitar amplifier was undertaken. This amplifier is divided into three distinct sections. The power distribution circuitry provides the proper voltages to safely operate all necessary components. The DSP and digital effects stage provides processing and allows the user to add digital effects to the original guitar sound. The amplification stage increases the power of the input signal to drive a loudspeaker. Due to several setbacks throughout the course of this project, the overall amplifier was not completed. All three of the sections were developed to working functionality, …

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"Buried-Anode" Technology Leads To Advanced Lithium Batteries, National Renewable Energy Laboratory Feb 2011

"Buried-Anode" Technology Leads To Advanced Lithium Batteries, National Renewable Energy Laboratory

Publications (E)

A technology developed at the National Renewable Energy Laboratory has sparked a start-up company that has attracted funding from the Advanced Projects Research Agency-Energy (ARPA-E). Planar Energy, Inc. has licensed NREL's "buried-anode" technology and put it to work in solid-state lithium batteries. The company claims its large-format batteries can achieve triple the performance of today's lithium-ion batteries at half the cost, and if so, they could provide a significant boost to the emerging market for electric and plug-in hybrid vehicles.

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Design Of Single-Carrier Frequency Domain Equalization (Sc-Fde) With Transmit Diversity For Wireless And Optical Communications, Kodzovi Acolatse Jan 2011

Design Of Single-Carrier Frequency Domain Equalization (Sc-Fde) With Transmit Diversity For Wireless And Optical Communications, Kodzovi Acolatse

Dissertations

As the demand of wireless service is rising, there is a need to transmit high-speed packets over the wireless communication channel. Broadband data transmission over wireless channels commonly faces the challenges of multipath fading channels, which are both time and frequency selective. There is then a need to design transmission techniques that can combat the adverse effects of the channel, and enable reliable high data rate wireless services. Orthogonal frequency division multiplexing (OFDM) has become widely accepted primarily because of its robustness against frequency selective fading channels, but it suffers a number of drawbacks such as high peak-to-average power ratio …

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Tin/Hfo2/Sio2/Si Gate Stacks Reliability : Contribution Of Hfo2 And Interfacial Sio2 Layer, Nilufa Rahim Jan 2011

Tin/Hfo2/Sio2/Si Gate Stacks Reliability : Contribution Of Hfo2 And Interfacial Sio2 Layer, Nilufa Rahim

Dissertations

Hafnium Oxide based gate stacks are considered to be the potential candidates to replace SiO2 in complementary metal-oxide-semiconductor (CMOS), as they reduce the gate leakage by over 100 times while keeping the device performance intact. Even though considerable performance improvement has been achieved, reliability of high-κ devices for the next generation of transistors (45nm and beyond) which has an interfacial layer (IL: typically SiO2) between high-κ and the substrate, needs to be investigated. To understand the breakdown mechanism of high-κ/SiO2 gate stack completely, it is important to study this multi-layer structure extensively. For example, (i) the …

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Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese Jan 2011

Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese

Dissertations

The ability to distribute time and frequency among a large population of interacting agents is of interest for diverse disciplines, inasmuch as it enables to carry out complex cooperative tasks. In a wireless sensor network (WSN), time/frequency synchronization allows the implementation of distributed signal processing and coding techniques, and the realization of coordinated access to the shared wireless medium. Large multi-hop WSN's constitute a new regime for network synchronization, as they call for the development of scalable, fully distributed synchronization algorithms. While most of previous research focused on synchronization at the application layer, this thesis considers synchronization at the lowest …

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Model Reference Control For Ultra-High Precision Positioning Systems, Lan Yu Jan 2011

Model Reference Control For Ultra-High Precision Positioning Systems, Lan Yu

Dissertations

Due to the increasing demands of high-density semiconductors, molecular biology, optoelectronics, and MEMS/NEMS in the past decades, control of ultra-high precision positioning using piezoelectricity has become an important area because of its high displacement resolution, wide bandwidth, low power consumption, and potential low cost. However, the relatively small displacement range limits its application. This work proposed a practical ultra-high precision piezoelectric positioning system with a complementary high displacement range actuation technology. Solenoids are low cost, high speed electromagnetic actuators which are commonly used in on-off mode only because of the inherent high nonlinear force-stroke characteristics and unipolar forces (push/pull) generated …

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Underwater Communication Via Particle Velocity Channels : Principles, Channel Models, And System Design, Huaihai Guo Jan 2011

Underwater Communication Via Particle Velocity Channels : Principles, Channel Models, And System Design, Huaihai Guo

Dissertations

A vector sensor is capable of measuring important non-scalar components of the acoustic field such as the particle velocity, which cannot be obtained by a single scalar pressure sensor. In the past few decades, extensive research has been conducted on the theory and design of vector sensors. On the other hand, underwater acoustic communication systems have been relying on scalar sensors only, which measure the pressure of the acoustic field. By taking advantage of the vector components of the acoustic field, such as the particle velocity, the vector sensor can be used for detecting the transmitted data. In this dissertation, …

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Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle Jan 2011

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …

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Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle Jan 2011

Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx acts as the sound source, providing a quasi-periodic excitation of the vocal tract. Following a total laryngectomy, some people speak using an electrolarynx which employs an electromechanical actuator to perform the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the monotonic sound emitted, the need for a free-hand to operate the device, and the difficulty experienced by many laryngectomees in adapting to its use. One improvement to the electrolarynx, which clinicians and users frequently suggest, is the provision of a convenient hands-free control facility. This would allow more natural use of …

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Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell Jan 2011

Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell

Articles

We report the fabrication and characterization of a lead-silicate glass microsphere resonator. We show that at the wavelengths near 1555 nm high Q modes can be efficiently excited from a 109 μm diameter lead-silicate glass microsphere via evanescent coupling using a tapered silica fiber with a waist diameter of 2 μm. Resonances with Q-factors as high as 0.9×107 were observed. This is very close to the theoretical material-limited Q-factor and is the highest Q-factor reported so far from a nonlinear glass microsphere.

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Virtualization And Self-Organization For Utility Computing, Mehdi Saleh Jan 2011

Virtualization And Self-Organization For Utility Computing, Mehdi Saleh

Electronic Theses and Dissertations

We present an alternative paradigm for utility computing when the delivery of service is subject to binding contracts; the solution we propose is based on resource virtualization and a selfmanagement scheme. A virtual cloud aggregates set virtual machines to work in concert for the tasks specified by the service agreement. A first step for the establishment of a virtual cloud is to create a scale-free overlay network through a biased random walk; scale-free networks enjoy a set of remarkable properties such as: robustness against random failures, favorable scaling, and resilience to congestion, small diameter, and average path length. Constrains such …

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The Performance And Power Impact Of Using Multiple Dram Address Mapping Schemes In Multicore Processors, Rami Jadaa Jan 2011

The Performance And Power Impact Of Using Multiple Dram Address Mapping Schemes In Multicore Processors, Rami Jadaa

Electronic Theses and Dissertations

Lowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic mapping scheme over the fixed one. Results show that applications’ performance varies according to the mapping scheme used, and a dynamic mapping scheme achieves up to 2x …

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Design And Simulation Of Cmos Active Mixers, Allen Gibson Jan 2011

Design And Simulation Of Cmos Active Mixers, Allen Gibson

Electronic Theses and Dissertations

This paper introduces a component of the Radio Frequency transceiver called the mixer. The mixer is a critical component in the RF systems, because of its ability for frequency conversion. This passage focuses on the design analysis and simulation of multiple topologies for the active down-conversion mixer. This mixer is characterized by its important design properties which consist of conversion gain, linearity, noise figure, and port isolation. The topologies that are given in this passage range from the most commonly known mixer design, to implemented design techniques that are used to increase the mixers important design properties as the demand …

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The Acquisition Of Lexical Knowledge From The Web For Aspects Of Semantic Interpretation, Hansen A. Schwartz Jan 2011

The Acquisition Of Lexical Knowledge From The Web For Aspects Of Semantic Interpretation, Hansen A. Schwartz

Electronic Theses and Dissertations

This work investigates the effective acquisition of lexical knowledge from the Web to perform semantic interpretation. The Web provides an unprecedented amount of natural language from which to gain knowledge useful for semantic interpretation. The knowledge acquired is described as common sense knowledge, information one uses in his or her daily life to understand language and perception. Novel approaches are presented for both the acquisition of this knowledge and use of the knowledge in semantic interpretation algorithms. The goal is to increase accuracy over other automatic semantic interpretation systems, and in turn enable stronger real world applications such as machine …

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Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon Jan 2011

Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Articles

In this paper a technical review of parallel operation of power electronics inverters for load sharing conditions in distributed generation (DG) network is presented. Emphasis is given to parallel operation of Active Power Filters (APFs) as they are widely used to mitigate load current disturbances into DG networks. Discussions on recent advances in control strategies as applied to APFs are presented.

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Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang Jan 2011

Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang

Electronic Theses and Dissertations

In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under …

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Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf Jan 2011

Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf

Electronic Theses and Dissertations

The integration of high-quality (Q)-factor 3-D filters with highly efficient antennas is addressed in this dissertation. Integration of filters and antennas into inseparable units eliminates the transitions between the otherwise separate structures resulting in more compact and efficient systems. The compact, highly efficient integrated 3-D filter/antenna systems, enabled by the techniques developed herein, allow for the realization of integrated RF front ends with significantly- reduced form factors. Integration of cavity filters with slot antennas in a single planar substrate is first demonstrated. Due to the high Q factor of cavity resonators, the efficiency of the integrated filter/antenna system is found …

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Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure Jan 2011

Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure

Electronic Theses and Dissertations

There is a tremendous volume of data being generated in today’s world. As organizations around the globe realize the increased importance of their data as being a valuable asset in gaining a competitive edge in a fast-paced and a dynamic business world, more and more attention is being paid to the quality of the data. Advances in the fields of data mining, predictive modeling, text mining, web mining, business intelligence, health care analytics, etc. all depend on clean, accurate data. That one cannot effectively mine data, which is dirty, comes as no surprise. This research is an exploratory study of …

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Analysis Of Behaviors In Crowd Videos, Ramin Mehran Jan 2011

Analysis Of Behaviors In Crowd Videos, Ramin Mehran

Electronic Theses and Dissertations

In this dissertation, we address the problem of discovery and representation of group activity of humans and objects in a variety of scenarios, commonly encountered in vision applications. The overarching goal is to devise a discriminative representation of human motion in social settings, which captures a wide variety of human activities observable in video sequences. Such motion emerges from the collective behavior of individuals and their interactions and is a significant source of information typically employed for applications such as event detection, behavior recognition, and activity recognition. We present new representations of human group motion for static cameras, and propose …

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Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma Jan 2011

Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma

Electronic Theses and Dissertations

Traditionally, radio spectrum has been statically allocated to wireless service providers (WSPs). Regulators, like FCC, give wireless service providers exclusive long term licenses for using specific range of frequencies in particular geographic areas. Moreover, restrictions are imposed on the technologies to be used and the services to be provided. The lack of flexibility in static spectrum allocation constrains the ability to make use of new technologies and the ability to redeploy the spectrum to higher valued uses, thereby resulting in inefficient spectrum utilization [23, 38, 42, 62, 67]. These limitations have motivated a paradigm shift from static spectrum allocation towards …

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Global Secure Sets Of Trees And Grid-Like Graphs, Yiu Yu Ho Jan 2011

Global Secure Sets Of Trees And Grid-Like Graphs, Yiu Yu Ho

Electronic Theses and Dissertations

Let G = (V, E) be a graph and let S ⊆ V be a subset of vertices. The set S is a defensive alliance if for all x ∈ S, |N[x] ∩ S| ≥ |N[x] − S|. The concept of defensive alliances was introduced in [KHH04], primarily for the modeling of nations in times of war, where allied nations are in mutual agreement to join forces if any one of them is attacked. For a vertex x in a defensive alliance, the number of neighbors of x inside the alliance, plus the vertex x, is at least the number …

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A Contextual Approach To Learning Collaborative Behavior Via Observation, Cynthia L. Johnson Jan 2011

A Contextual Approach To Learning Collaborative Behavior Via Observation, Cynthia L. Johnson

Electronic Theses and Dissertations

This dissertation describes a novel technique to creating a simulated team of agents through observation. Simulated human teamwork can be used for a number of purposes, such as expert examples, automated teammates for training purposes and realistic opponents in games and training simulation. Current teamwork simulations require the team member behaviors be programmed into the simulation, often requiring a great deal of time and effort. None are able to observe a team at work and replicate the teamwork behaviors. Machine learning techniques for learning by observation and learning by demonstration have proven successful at observing behavior of humans or other …

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Evaluating The Effectiveness Of Peak Power Tracking Technologies For Solar Arrays On Small Spacecraft, Daniel Martin Erb Jan 2011

Evaluating The Effectiveness Of Peak Power Tracking Technologies For Solar Arrays On Small Spacecraft, Daniel Martin Erb

University of Kentucky Master's Theses

The unique environment of CubeSat and small satellite missions allows certain accepted paradigms of the larger satellite world to be investigated in order to trade performance for simplicity, mass, and volume. Peak Power Tracking technologies for solar arrays are generally implemented in order to meet the End-of-Life power requirements for satellite missions given radiation degradation over time. The short lifetime of the generic satellite mission removes the need to compensate for this degradation. While Peak Power Tracking implementations can give increased power by taking advantage and compensating for the temperature cycles that solar cells experience, this comes at the expense …

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Multi-Pose Face Recognition And Tracking System, Binu Muraleedharan Nair, Jacob Foytik, Richard Tompkins, Yakov Diskin, Theus Aspiras, Vijayan K. Asari Jan 2011

Multi-Pose Face Recognition And Tracking System, Binu Muraleedharan Nair, Jacob Foytik, Richard Tompkins, Yakov Diskin, Theus Aspiras, Vijayan K. Asari

Electrical and Computer Engineering Faculty Publications

We propose a real time system for person detection, recognition and tracking using frontal and profile faces. The system integrates face detection, face recognition and tracking techniques. The face detection algorithm uses both frontal face and profile face detectors by extracting the 'Haar' features and uses them in a cascade of boosted classifiers. The pose is determined from the face detection algorithm which uses a combination of profile and frontal face cascades and, depending on the pose, the face is compared with a particular set of faces having the same range for classification. The detected faces are recognized by projecting …

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Fluorinated Templates For Energy-Related Nanomaterials And Applications, Mohammed J. Meziani, Fushen Lu, Li Cao, Christopher E. Bunker, Elena A. Guliants, Ya-Ping Sun Jan 2011

Fluorinated Templates For Energy-Related Nanomaterials And Applications, Mohammed J. Meziani, Fushen Lu, Li Cao, Christopher E. Bunker, Elena A. Guliants, Ya-Ping Sun

Electrical and Computer Engineering Faculty Publications

Fluorinated ionomer membranes, as represented by the commercially available Nafion films, are macroscopically homogeneous and optically transparent but microscopically inhomogeneous with the presence of nanoscale hydrophilic cavities. These cavities serve as nanoscale reactors for the synthesis of nanoparticles from a variety of materials. The membranes with embedded nanoscale semiconductors, still optically transparent, have been used as sheet-photocatalysts for energy conversion applications, while those with embedded reactive metals used as nano-energetic materials for hydrogen generation and beyond. This chapter provides an overview on the templated synthesis of nanomaterials in fluorinated ionomer membranes and the various energy-related applications of this unique class …

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Comparison Of Turbulence-Induced Scintillations For Multi-Wavelength Laser Beacons Over Tactical (7 Km) And Long (149 Km) Atmospheric Propagation Paths, Mikhail Vorontsov, Venkata S. Rao Gudimetla, Gary W. Carhart, Thomas Weyrauch, Svetlana Lachinova, Ernst Polnau, Joseph Rierson, Leonid A. Beresnev, Jony Jiang Liu, Jim F. Riker Jan 2011

Comparison Of Turbulence-Induced Scintillations For Multi-Wavelength Laser Beacons Over Tactical (7 Km) And Long (149 Km) Atmospheric Propagation Paths, Mikhail Vorontsov, Venkata S. Rao Gudimetla, Gary W. Carhart, Thomas Weyrauch, Svetlana Lachinova, Ernst Polnau, Joseph Rierson, Leonid A. Beresnev, Jony Jiang Liu, Jim F. Riker

Electrical and Computer Engineering Faculty Publications

We report results of the experimental analysis of atmospheric effects on laser beam propagation over two distinctive propagation paths: a long-range (149 km) propagation path between Mauna Loa (Island of Hawaii) and Haleakala (Island of Maui) mountains, and a tactical-range (7 km) propagation path between the roof of the Dayton Veterans Administration Medical Center (VAMC) and the Intelligent Optics Laboratory (IOL/UD) located on the 5th floor of the University of Dayton College Park Center building. Both testbeds include three laser beacons operating at wavelengths 532 nm, 1064 nm, and 1550 nm and a set of identical optical receiver systems with …

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Spatio-Temporal Cardiac Pacing Sites Localization And Time Varying Pericardium Potential Maps Projection Using Ecg Precordial Leads And A Single Moving Dipole Model, Jaime R. De La Cruz Jan 2011

Spatio-Temporal Cardiac Pacing Sites Localization And Time Varying Pericardium Potential Maps Projection Using Ecg Precordial Leads And A Single Moving Dipole Model, Jaime R. De La Cruz

Open Access Theses & Dissertations

A novel non-invasive method for the spatiotemporal localization of the sites of strongest cardiac activity, and for the creation of time varying Pericardium Potential Maps (PPM), with the use of patients' ECG precordial leads, is proposed in this Thesis study. Compared to previous studies, which analyze electrocardiograms in either time domain or spatial domain, the proposed method has the advantage of a simultaneous spatiotemporal electrocardiograph analysis and a 3-D visualization of pericardium potentials maps, as well as, the pericardium surface polarization patterns during the cardiac cycle. The spatial properties added to the electrocardiogram allow for the analysis of specific regions …

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Assessment And Evaluation Of Peripheral Neuropathy From Diabetic Mellitus Using Systems Analysis Approach, Oscar Alonso Espino Jan 2011

Assessment And Evaluation Of Peripheral Neuropathy From Diabetic Mellitus Using Systems Analysis Approach, Oscar Alonso Espino

Open Access Theses & Dissertations

Currently in America 1 out of every 10 residents suffers from diabetes, and this tendency is likely to grow up to "1 of every 3" by the year [6]. Diabetes exhibits several complications. In 2005, the lead cause of stroke and heart disease was diabetes, 68% of the cases [1]. In 2008, 44% of kidney failure was associated with diabetes [1]. 60 to 70 % of cases of diabetes have a mild to severe nervous system damage [1]. Diabetic patients who have developed peripheral neuropathy tend to also develop foot ulceration. In an advanced stage a foot ulcer can lead …

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Investigation And Experimental Measurement Of Scissor Blade Cutting Forces Using Fiber Bragg Grating Sensors., Dean Callaghan, Ginu Rajan, Mark Mcgrath, Eugene Dermot Coyle Professor, Yuliya Semenova, Gerald Farrell Jan 2011

Investigation And Experimental Measurement Of Scissor Blade Cutting Forces Using Fiber Bragg Grating Sensors., Dean Callaghan, Ginu Rajan, Mark Mcgrath, Eugene Dermot Coyle Professor, Yuliya Semenova, Gerald Farrell

Articles

This paper investigated the application of FBG sensors in the measurement of scissor blade–tissue interaction forces. Sensor placement at the blade–tissue interaction site provides the basis for increased force measurement accuracy, without compromising the functionality of the instrument. This increased accuracy provided the foundation for in-depth analysis of the force components generated during typical scissor cutting cycles. Theoretical analysis and experimental investigation explored the decoupling of the major forces present during cutting. The isolation of tissue-fracture forces from inter-blade friction forces was carried out. This is useful as knowledge of the fracture properties of biological tissues can be diff cult …

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