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2010

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Articles 3901 - 3930 of 5375

Full-Text Articles in Engineering

High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer Jan 2010

High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer

Mechanical Engineering Faculty Research

A Science, Technology, Engineering and Math (STEM) summer Bridge Program was developed for high school students. The program was designed to encourage students to consider choosing an engineering major in college and to explore STEM as a future career. This was accomplished through a 10-week program involving multidisciplinary research activities. The participants in the program included 33 high school students. Among former participants in position to make a choice in terms of attending college, 100% had chosen to continue on in college, and 86% had chosen to major in a STEM area. The results indicated that that the program had …

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Risk And System-Of-Systems: Toward A Unified Concept, C. Ariel Pinto, Michael K. Mcshane, Rani Kady Jan 2010

Risk And System-Of-Systems: Toward A Unified Concept, C. Ariel Pinto, Michael K. Mcshane, Rani Kady

Engineering Management & Systems Engineering Faculty Publications

The scope of this paper is the survey of both fundamental and most recent publications in system-of-systems, business and insurance, as well as risk analysis, modeling, and management for the purpose of better describing the concept of risk in recognition of emergence and complexity which characterizes many systems within the concern of engineering and business managers. The ultimate goal is to provide engineering and business managers the necessary perspective on the concept of risk and in its management for the next generation of sustainable systems - including various descriptions of risk and discussion of the relevance of properties of system-of-systems …

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Turbidity Effects On Solar Radiation Attenuation And Reflection, Andrew Hobson Jan 2010

Turbidity Effects On Solar Radiation Attenuation And Reflection, Andrew Hobson

Browse All Undergraduate research

Limited water resources in Southern Utah with the competing interests of humans and native fishes require careful management. High instream temperatures resulting from low flows are a consideration in managing the Virgin River for two endangered fish species. Throughout these periods, fish behavior changes have been observed during those high turbidity. One hypothesis was that high turbidity decreased the amount of solar radiation in the water column due to increased reflection at the water surface resulting in reduced instream temperatures. To quantify the extent of changes in incoming energy to the river, a water tank was constructed to measure the …

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On The Applications Of Deterministic Chaos For Encrypting Data On The Cloud, Jonathan Blackledge, Nikolai Ptitsyn Jan 2010

On The Applications Of Deterministic Chaos For Encrypting Data On The Cloud, Jonathan Blackledge, Nikolai Ptitsyn

Conference papers

Cloud computing is expected to grow considerably in the future because it has so many advantages with regard to sale and cost, change management, next generation architectures, choice and agility. However, one of the principal concerns for users of the Cloud is lack of control and above all, data security. This paper considers an approach to encrypting information before it is ‘place’ on the Cloud where each user has access to their own encryption algorithm, an algorithm that is based on a set of Iterative Function Systems that outputs a chaotic number stream, designed to produce a cryptographically secure cipher. …

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Generating System Requirements For A Mobile Digital Evidence Collection System: A Preliminary Step Towards Enhancing The Forensic Collection Of Digital Devices, Ibrahim Baggili Jan 2010

Generating System Requirements For A Mobile Digital Evidence Collection System: A Preliminary Step Towards Enhancing The Forensic Collection Of Digital Devices, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Collecting digital devices in a forensically sound manner is becoming more critical since 80% of all cases have some sort of digital evidence involved in them (Rogers, 2006, p. 1) .The process of documenting and tagging digital devices is cumbersome and involves details that might not apply to other types of evidence, since each evidence item has unique physical characteristics (Hesitis & Wilbon, 2005, p. 17). The process becomes less manageable when a large number of digital devices are seized. This paper examines the information and issues investigators should be aware of when collecting digital devices at crime scenes. Furthermore, …

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Full Wave Simulation Of An Electrostatic Discharge Generator Discharging In Air Discharge Mode Into A Product And Quantify Channel Performance Utilizing Novel Time Domain Convolution Method, Dazhao Liu Jan 2010

Full Wave Simulation Of An Electrostatic Discharge Generator Discharging In Air Discharge Mode Into A Product And Quantify Channel Performance Utilizing Novel Time Domain Convolution Method, Dazhao Liu

Masters Theses

"In the first section, it introduces a methodology to simulate the currents and fields during an air discharge ESD into a product by combining a linear description of the behavior of the DUT with a non-linear arc resistance equation. The most commonly used test standard IEC 61000-4-2 requires using contact mode discharges to metallic surfaces and air discharge mode to non-conducting surfaces. In contact mode, an Electrostatic Discharge (ESD) generator is a linear system. In air discharge mode, a highly non-linear arc is part of the current loop. This paper proposes a method that combines the linear ESD generator full …

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Effect Of Pre-Processing On Binarization, Elisa Barney Smith, Laurence Likforman-Sulem, Jérôme Darbon Jan 2010

Effect Of Pre-Processing On Binarization, Elisa Barney Smith, Laurence Likforman-Sulem, Jérôme Darbon

Electrical and Computer Engineering Faculty Publications and Presentations

The effects of different image pre-processing methods for document image binarization are explored. They are compared on five different binarization methods on images with bleed through and stains as well as on images with uniform background speckle. The binarization method is significant in the binarization accuracy, but the pre-processing also plays a significant role. The Total Variation method of pre-processing shows the best performance over a variety of pre-processing methods.

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Wi-Fi Localization Using Rssi Fingerprinting, Michael Quan, Eduardo Navarro, Benjamin Peuker Jan 2010

Wi-Fi Localization Using Rssi Fingerprinting, Michael Quan, Eduardo Navarro, Benjamin Peuker

Computer Engineering

Wireless Local Area Networks using Wi-Fi is becoming more and more ubiquitous. As such, they provide a potential pre-built infrastructure for small area localization. This project serves as a proof of concept for a playground child tracking system to be deployed at Cal Poly's Child Development Playground Lab. The two main options for doing Wi-Fi localization are triangulation and fingerprinting. Triangulation involves mapping signal strength as a function of distance while fingerprinting creates a probability distribution of signal strengths at a given location and uses a map of these distributions to predict a location given signal strength samples. The triangulation …

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The Relevance Of Time-To-Digital Converters To Small Platform Direction Finding Systems, Paul Jeffrey Nelson Jan 2010

The Relevance Of Time-To-Digital Converters To Small Platform Direction Finding Systems, Paul Jeffrey Nelson

Electronic Theses and Dissertations

This thesis explores a Time-Difference-of-Arrival (TDOA) approach to radio direction finding, utilizing picosecond-resolution Time-to-Digital Converters (TDCs). By measuring the relative time of arrival of a pulsed RF signal impinging on an antenna array, direction of arrival (DOA) can be ascertained. This technology enables versatile DOA calculation on platforms only several meters in length, and offers various size, weight, power, and cost advantages when compared to present DF technologies. A short baseline S-band TDOA DF system utilizing TDCs is designed, fabricated, and tested in a laboratory environment. This research suggests that such a DF system based on TDCs provides sufficient accuracy …

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Complex Systems Architecting Using Design Primitives, Comparative Analysis And Fuzzy Analytical Feedback, Jason Paul Dauby, Cihan H. Dagli Jan 2010

Complex Systems Architecting Using Design Primitives, Comparative Analysis And Fuzzy Analytical Feedback, Jason Paul Dauby, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Modern systems are increasing in complexity. It is advantageous to understand and control this complexity as early in the design lifecycle as possible. The system architecting community must reconcile the inherent ambiguity in a system description with the need for analytical assessments of system attributes so as to increase the likelihood of developmental success. Presently, it is commonplace to decompose systems and subsystems using assumptions of idealized severability and reliance on superposition to estimate composite performance. It is suggested that these assumptions can result in errant oversimplification and represent an opportunity for new systems engineering research. This paper introduces a …

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Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Thaddaeus Bode, Yong-Rak Kim Jan 2010

Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Thaddaeus Bode, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

No abstract provided.

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Distributed Reasoning With El++ Using Mapreduce, Frederick Maier, Raghava Mutharaju, Pascal Hitzler Jan 2010

Distributed Reasoning With El++ Using Mapreduce, Frederick Maier, Raghava Mutharaju, Pascal Hitzler

Computer Science and Engineering Faculty Publications

It has recently been shown that the MapReduce framework for distributed computation can be used effectively for large-scale RDF Schema reasoning, computing the deductive closure of over a billion RDF triples within a reasonable time. Later work has carried this approach over to OWL Horst. In this paper, we provide a MapReduce algorithm for classifying knowledge bases in the description logic EL++, which is essentially the OWL 2 profile OWL 2 EL. The traditional EL++ classification algorithm is recast into a form compatible with MapReduce, and it is shown how the revised algorithm can be realized within …

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Improving Outcomes In Outsourced Product Development: A Joint Consultant-Client Perspective, William J. Palm, Daniel E. Whitney Jan 2010

Improving Outcomes In Outsourced Product Development: A Joint Consultant-Client Perspective, William J. Palm, Daniel E. Whitney

Engineering, Computing & Construction Management Faculty Publications

Although firms increasingly outsource front end product development activities to production suppliers or design consultants, this practice has received little scholarly attention. The few existing academic studies report high failure rates but generally present only the client firms’ view of the causes. Our first results from in-depth interviews of both clients and consultants give a richer picture of enablers of success and causes of failure. We confirm some previous findings(internal divisions within the client, “poor communication” between parties),identify new ones (inadequate client capabilities, failure to transfer design intent), and combine them into a comprehensive model of outsourced product development that …

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Optimal Integrator-Less Tracking Controller For Uncertain Systems, Anusha Mannava Jan 2010

Optimal Integrator-Less Tracking Controller For Uncertain Systems, Anusha Mannava

Masters Theses

"Tracking controllers are designed to drive the system on the desired trajectory with minimum error. In real life, all systems have uncertainties such as friction, modeling inaccuracies or damage that cause the performance to deviate from the ideal response. This research is aimed at addressing the tracking problem in the optimal context and a generalized method to handle the uncertainties is proposed. In the first paper, an optimal tracking controller without an integral component is formulated for a linear system. This design can handle time varying, non-zero references and effectively alleviates the risk of 'wind up'. A neural network based …

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Rotational Relaxation Times Of Individual Compounds With Simulations Of Molecular Asphalt Models, Liqun Zhang, Michael L. Greenfield Jan 2010

Rotational Relaxation Times Of Individual Compounds With Simulations Of Molecular Asphalt Models, Liqun Zhang, Michael L. Greenfield

Chemical, Biomolecular, and Materials Engineering Faculty Publications

The dynamical properties of a complex system incorporate contributions from the diverse components from which it is constituted. To study this relationship in a multicomponent system, relaxation times based on rotation autocorrelation functions in molecular dynamics simulations were analyzed for molecules in two sets of unmodified and polymer-modified model asphalt/bitumen systems over 298–473 K. The model asphalt systems were proposed previously to approximate the chemical and mechanical properties of real asphalts. Relaxations were modeled using a modified Kaulrausch–Williams–Watts function and were based on the third Legendre polynomial of normal vector time correlation functions for aromatic species asphaltene, polar aromatic, naphthene …

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Partitioning Of Perfluorooctanoate Into Phosphatidylcholine Bilayers Is Chain Length-Independent, Wei Xie, Geoffrey D. Bothun, Hans-Joachim Lehmler Jan 2010

Partitioning Of Perfluorooctanoate Into Phosphatidylcholine Bilayers Is Chain Length-Independent, Wei Xie, Geoffrey D. Bothun, Hans-Joachim Lehmler

Chemical, Biomolecular, and Materials Engineering Faculty Publications

The chain length dependence of the interaction of PFOA, a persistent environmental contaminant, with dimyristoyl- (DMPC), dipalmitoyl- (DPPC) and distearoylphosphatidylcholine (DSPC) was investigated using steady-state fluorescence anisotropy spectroscopy, differential scanning calorimetry (DSC) and dynamic light scattering (DLS). PFOA caused a linear depression of the main phase transition temperature Tm while increasing the width of the phase transition of all three phosphatidylcholines. Although PFOA's effect on Tm and the transition width decreased in the order DMPC > DPPC > DSPC, its relative effect on the phase behavior was largely independent of the phosphatidylcholine. PFOA caused swelling of DMPC but not DPPC …

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A Multiscale Gibbs-Helmholtz Constrained Cubic Equation Of State, Angelo Lucia Jan 2010

A Multiscale Gibbs-Helmholtz Constrained Cubic Equation Of State, Angelo Lucia

Chemical, Biomolecular, and Materials Engineering Faculty Publications

This paper presents a radically new approach to cubic equations of state (EOS) in which the Gibbs-Helmholtz equation is used to constrain the attraction or energy parameter, a. The resulting expressions for a(T, p) for pure components and a(T, p, x) for mixtures contain internal energy departure functions and completely avoid the need to use empirical expressions like the Soave alpha function. Our approach also provides a novel and thermodynamically rigorous mixing rule for a(T, p, x).When the internal energy departure function is computed using Monte …

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System For Rapidly Boring Through Materials, W. A. Berger, J. A. Carter, C. Davey, Marian Mazurkiewicz, R. M. Pell, R. A. Spalletta Jan 2010

System For Rapidly Boring Through Materials, W. A. Berger, J. A. Carter, C. Davey, Marian Mazurkiewicz, R. M. Pell, R. A. Spalletta

Mining Engineering Faculty Research & Creative Works

The present invention is a self-contained, high-energy liquid rock-boring system that will bore a small-diameter access hole [5] several hundred meters through hard granite and other obstacles within minutes of deployment. It employs a land unit [100] platform subsystem [1000] with an energetic fluid fuel reservoir [1300] and a boring subsystem [3000] having a plurality of pulsejets [3100]. Each pulsejet [3100] repeatedly ignites the energetic fluid [7] causing a plurality of rapidly-expanding gas bubbles [3250] which create and force a plurality liquid slugs [10] ahead of them rapidly out through a nozzle [3260] causing the slugs [10] to impact against …

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Development Of A Preliminary Cost Estimation Method For Water Treatment Plants, Jwala Raj Sharma Jan 2010

Development Of A Preliminary Cost Estimation Method For Water Treatment Plants, Jwala Raj Sharma

Civil Engineering Theses - Archive

Reliable cost estimates for construction, and operation and maintenance (O&M) of water treatment plants are essential for their project planning and design. During the planning phases of the project, preliminary cost estimates are developed for major project components, and for screening of alternatives.Construction and O&M cost curves are widely used for developing preliminary cost estimates. This method is time consuming and there is possibility of human errors. Therefore, for this thesis, construction, and O&M cost equations were developed considering historical cost data for different unit operations and processes involved in a water treatment plant. These equations were developed from historical …

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Solution To Incompressible Navier Stokes Equations By Using Finite Element Method, Wanchai Jiajan Jan 2010

Solution To Incompressible Navier Stokes Equations By Using Finite Element Method, Wanchai Jiajan

Mechanical and Aerospace Engineering Theses - Archive

The finite element method has become a popular method for the solution of the incompressible Navier-Stokes equations. High Reynolds number cases require fine meshes so computational efficiency becomes an important factor in algorithm and code development. In this work, a Galerkin finite element method is proposed to solve the two dimensional incompressible Navier-Stokes equations. This approach typically leads to a sparse and indefinite matrix that is difficult to solve efficiently. The formation of an indefinite matrix is avoided in the present work by introducing an artificial compressibility term in the continuity equation. The concept of this method is to transform …

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Finite Element Analysis Of Stresses In Involute Spur & Helical Gear, Shreyash D. Patel Jan 2010

Finite Element Analysis Of Stresses In Involute Spur & Helical Gear, Shreyash D. Patel

Mechanical and Aerospace Engineering Theses - Archive

Developing an analytical approach and modeling procedure to evaluate stress distribution under velocity and moment would provide a useful tool to improve spur gear design with high efficiency & low cost. The purpose of this work is to analyze and validate the stress distribution in spur & helical gears using contemporary commercial FEM program ANSYS coupled with the Pro/E solid modeler. Gear profiles are created in Pro Engineer using the Relation and Equation modeling procedure so as to make it a general model, dependant on certain key features like number of teeth, diametral pitch, and pressure and helix angle. These …

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Effects Of Curvature On The Stresses Of A Curved Laminated Beams Subjected To Bending, Thien Nguyen Jan 2010

Effects Of Curvature On The Stresses Of A Curved Laminated Beams Subjected To Bending, Thien Nguyen

Mechanical and Aerospace Engineering Theses - Archive

In aircraft structural applications, curved laminated beam structures are often used as part of the internal structure. If the curved composite structure is subjected to bending that tends to flatten or compress the composite structure, interlaminar stresses can be generated in the thickness direction of the composites. These interlaminar stresses are the major factor of delamination failure. Besides these stresses, the in-plane stresses can be also affected by the pre-existence of the beam curvature. This research has studied the variation of both tangential and radial stresses with respect to the changing in curvature, stacking sequence, and fiber orientation in a …

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Failure Assessment In Aerospace Systems Via Integrated Multi-Functional Sensors, Ismail Erkin Gonenli Jan 2010

Failure Assessment In Aerospace Systems Via Integrated Multi-Functional Sensors, Ismail Erkin Gonenli

Electrical Engineering Dissertations - Archive

Integrated sensors fabricated on flexible substrates show lots of promise due to their ability to conform on non-planar surfaces. Potential applications could be smart-skin and wearable electronics which can be used on prosthetic devices or in harsh environments to provide with the sense of feel of the ambient. Design, fabrication and characterization of MEMS piezoresistive pressure sensors and capacitive accelerometers were done on Si and flexible polymer substrates using surface micromachining to be used on aerospace applications. Devices were successfully tested on planar surfaces.For the pressure sensor fabrication, Si3N4 was used as a membrane material due to its linearity and …

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The Self-Heating Effects Of Bipolar Juction Transistors On The Functionality Of A Current Feedback Amplifier, Xuesong Xie Jan 2010

The Self-Heating Effects Of Bipolar Juction Transistors On The Functionality Of A Current Feedback Amplifier, Xuesong Xie

Electrical Engineering Dissertations - Archive

Self-heating effects strongly affect the performance of modern silicon-on-insulator (SOI) bipolar junction transistors. This research work does an extensive analysis of self-heating effects on large-signal behavior, small-signal behavior and transient operation of bipolar junction transistors. The two mechanisms in which device temperature affects large-signal behavior of a BJT transistor are investigated, i.e. the common-emitter (CE) configuration is to be driven by a constant base-emitter voltage and a constant base current. It is shown that the output characteristic of a BJT transistor is less sensitive to self-heating under a fixed base current than a fixed base-emitter voltage. A simple method of …

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High Detectivity Pyroelectric Infrared Detector, Annand Balasubramaniyam Jan 2010

High Detectivity Pyroelectric Infrared Detector, Annand Balasubramaniyam

Electrical Engineering Theses - Archive

The sensors which measure physical quantities by sensing them as thermal quantities and then converting the thermal signals into electrical signals are called thermal sensors. One such type of thermal sensor is a pyroelectric infrared sensor. Thermal sensors are not popular mainly because they are slow devices, and they have low sensitivity when compared to photon detectors. One major advantage of thermal detectors over photon detectors is that they can operate at room temperature. This is one of the main motivations for this research. The aim of the thesis is to design an uncooled, high detectivity pyroelectric infrared detector. The …

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Charge Pump Circuit, Paras Shah Jan 2010

Charge Pump Circuit, Paras Shah

Electrical Engineering Theses - Archive

The sole aim of this work is to show how to generate higher voltages greater than the power supply voltage. This idea is implemented using transistors and capacitors on silicon and is called a charge pump circuit. A charge pump circuit is implemented as a voltage doubler circuit in this work using 0.25um gate length technology. A 6-stage Dickson charge pump circuit was designed to produce a 15 V output from a 5 V supply using two phase non-overlapping clock signals that drive the charge pump. It also describes the advanced architectures with complex circuit design and dynamic techniques for …

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Passive Rf Sensors And Wireless Sensor Interrogation, Srikar Deshmukh Jan 2010

Passive Rf Sensors And Wireless Sensor Interrogation, Srikar Deshmukh

Electrical Engineering Theses - Archive

Recently, a new type of passive sensor called the antenna sensor has been developed. The antenna sensor incorporates a patch antenna as the sensing element as well as the data transmitting element. Physical factors such as strain and ground plane crack cause the patch antenna resonant frequency to change. By measuring the change in patch antenna resonant frequency these physical factors can be quantified.Conventional resonant frequency measurement methods require a wired connection to the antenna sensor. The wireless interrogation technique eliminates this requirement while offering all the advantages that a wireless sensor interface offers over a wired sensor interface. In …

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A High Fill Factor Cmos Image Sensor For Ir Camera Applications, Daniel Mcbride Jan 2010

A High Fill Factor Cmos Image Sensor For Ir Camera Applications, Daniel Mcbride

Electrical Engineering Theses - Archive

In this thesis, a unit cell for high-SNR applications is presented. The proposed circuit is significantly smaller than other circuits that perform dark current subtraction because less circuitry is used inside the unit cell. The proposed circuit uses only two transistors and one resistor inside each unit cell to suppress the dark current. The size of the circuit in the layout is 25 um x 25 µm. With this new unit cell and routing approach, the size of the unit cell was reduced by 300% compared to other circuits which also suppress dark current.

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Implementation Of Security Within Gen2 Protocol, Shesh Kumar Jagannatha Jan 2010

Implementation Of Security Within Gen2 Protocol, Shesh Kumar Jagannatha

Electrical Engineering Theses - Archive

In this thesis, I propose and evaluate several methods to integrate security within the identification process and memory access processes of the ISO 18000-6C (or GEN2) passive UHF radio frequency identification (RFID) protocol. The RFID Tags are promiscuous and they emit their unique identifiers in clear upon interrogation from the Reader. They do not have a mutual authentication process to validate the Readers and Tags, this allows eavesdropping, illicit reading from a malicious Reader and counterfeit Tags. GEN2 Tags are being integrated into driver's licenses and being used for border crossing identities; thus, there is a need to secure both …

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Quantitative Variation Of Blood Pressure Dynamics During Sleep Apnea, Raichel Mary Alex Jan 2010

Quantitative Variation Of Blood Pressure Dynamics During Sleep Apnea, Raichel Mary Alex

Bioengineering Theses - Archive

Sleep Apnea is one of the major sleep disorders characterized by complete cessation or decline in breathing for about 10s or more during sleep, thereby adversely affecting the quality of sleep. Studies show that about 6 % of the US adult population suffers from obstructive sleep apnea, which in turn plays a major role in the development of hypertension, heart failure, stroke and is also responsible for reduced performance in everyday activities due to lack of quality sleep. In this study the physiological response to sleep apnea were determined using beat to beat blood pressure in both healthy subjects and …

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