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Detection of matrix cracking in a GFRP laminate using a fibre optic sensorBarton, Elena January 2000 (has links)
No description available.
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Chameleon Interference: Assessing Vulnerability of Magnetic Sensors to Spoofing and Signal injection attacks through Environmental interference in Mobile DevicesGleason, David Theodore 06 January 2023 (has links)
Embedded sensors are a fixture of most devices in the current computer industry. These small devices are used for a variety of purposes throughout many fields to collect whatever kind of information is needed by the user. From data on device acceleration to data on position relative to the Earth's magnetic field, embedded sensors can provide it for any number of tasks.
The advent of these devices has made work and research in the computer industry significantly easier but they are not without their drawbacks.
Most of these sensors operate by drawing external data from the environment through send and receive signals. This mode of operation leaves them vulnerable to external malicious users who seek access to the data being stored and handled by the sensors. Concerns over security and privacy of embedded sensor data has become a topic of great concern with the continued digitization of sensitive personal data.
Within the last five years, studies have shown the ability to manipulate embedded magnetic sensors in order to gain access to various forms of sensitive personal data. This is of great concern to the developers of mobile devices as most mobile devices possess embedded magnetic sensors. The vulnerability of sensors to external influence leads to concerns for both data privacy and degradation of public trust in the ability of their devices to keep their personal information safe and out of the wrong hands. Degradation of public trust in security methodologies is a major concern to many in the research and tech industry as much of the work conducted to advance both security and technology depends on large amounts of public data. If the public loses trust in the ability of the devices used by researchers to protect and ensure the safety of the data provided to them, then they may stop providing data which would then make the work of researchers and other tech workers considerably more difficult.
To address these concerns, this thesis will present an introduction to Magnetic sensor devices (a prominent tool for data collection), how these sensors work and the ways they handle data. We shall then examine the techniques used to interfere with the functioning and output of magnetic sensors employed by mobile devices. Finally, we shall examine existing techniques for defending against these kinds of attacks as well as propose potential new techniques. The end goal of this work is to provide a broader perspective on the nature of environmental/natural interference and its relationship to scientific study and technological advancement. Literature around this topic does exist, however, all existing works currently in the literature focus exclusively on one form of interference i.e., light which leads to a smaller/narrower perspective which this work seeks to remedy. The end result is meant to give a broader perspective of multiple forms of interference and their interrelations between each other than is possible by current perspectives due to their narrow lens. / Master of Science / Embedded sensors are small devices integrated into many mobile devices currently in the public market. These devices serve to collect environmental data of all kinds in order to perform a variety of functions. From directional calibration to magnetic orientation in relation to the magnetic north pole, sensors perform it all. This has led to a massive increase in computer power and quality of life for the general public but not without issue. The increase in storing personal/sensitive data to be processed by these devices has prompted a new breed of privacy concerns and problems to confront. In this thesis, we seek to show the influence and effects of five distinct types of interference rooted in the natural world on the functioning of magnetic sensor devices.
Through the experiments conducted in this work, it was found that the interference forms of sound, temperature, and electromagnetism could induce a 32-36 percent average decrease in standard deviation in the data being processed by the sensor. Temperature shifting as an interference form also showed the potential for sizeable impacts on sensor functioning in terms of both increases and decreases. The largest decrease in standard deviation observed was 122 percent from the experiments with low temperature shifting. This work shows the incredible power and influence that the forces of nature can have on everyday devices and their need for data from their environment. The results observed from the temperature shift experiments also highlight the danger of leaving temperature based cyber-attacks under researched. The main use of this work is to fill the void in the current literature created by temperature based cyber-attacks and hopefully spur more research to be conducted into this method of cyber threat.
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Detection of Endoscopic Looping During Colonoscopy Procedure Using Embedded Bending SensorsBruce, Michael P. 24 August 2015 (has links)
No description available.
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Estimation of Input Forces on a Cutting Tool using Strain Output SignalsMahato, Ram Pradip, Ma, Jiacheng January 2022 (has links)
Lathes are frequently used in industrial production. It is an important parameter to calculate the force exerted by the cutter head on the raw material. Knowing the force acting on the cutting tool will aid in predicting the displacement of the cutting edge as well as predict displacement of the workpiece. The main purpose of this paper is to find a way to calculate the force exerted on the cutting tool tip. The magnitude of the tooltip force is estimated without the use of a force sensor. Instead, strain sensors are used to collect strain signals, and acceleration sensors are used to collect acceleration signals. Combine these two signals to calculate the magnitude of force. The force-strain frequency response function is calculated. The force-strain FRF acts as a bridge connecting force and strain signals. Calculate the input force signal on the cutting tool tip using the strain signal. In this way, is available to obtain the force time-image. Changes in force can be predicted by looking for force-time laws. In this thesis using MATLAB software for simulation and actual experimental measurements. Verify the reliability of the calculation method. The method and MATLAB code for calculating force-strain FRF are researched and written. Simulate the cutting tool input-output model in MATLAB. Combined with the actual experimental measurement results, the accuracy and limitations of this calculation method are analyzed. Discuss directions for future work.
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Analyse des contraintes mecaniques et de la resistivite des interconnexions de cuivre des circuits integres : role de la microstructure et du confinement geometrique / Mechanical stress and resistivity analysis of the integrated circuits copper interconnections : microstructural and geometrical confinement effectVayrette, Renaud 07 February 2011 (has links)
L’évolution de la technologie microélectronique conduit à une densité d’intégration toujours plus forte des transistors. Les structures d’interconnexions en cuivre Damascène suivent cette tendance et doivent être maîtrisées en termes de fabrication, de performance et de robustesse, ces différents aspects étant intimement liés aux contraintes résiduelles et à la résistivité. Cette thèse vise à comprendre les mécanismes de génération de contraintes et identifier les différentes contributions à la résistivité de ces objets en fonction des conditions de recuit et des dimensions (de la centaine de nm à plusieurs µm). Pour ce faire, les rôles respectifs de la microstructure et des dimensions de films et de lignes de cuivre électrodéposés ont été découplés sur la base de modèles analytiques intégrants des paramètres microstructuraux et géométriques. La microstructure a été analysée principalement à partir de cartographies d’orientations cristallines réalisées par EBSD. Dans le cas des lignes de cuivre de 0.2 à 1 µm de large, les contraintes résiduelles ont été déduites de l’exploitation de nano-capteurs pivotants spécialement élaborés. Les résultats obtenus montrent qu’indépendamment de la température de recuit, l’augmentation de résistivité et de contraintes résiduelles observée vers les faibles dimensions est le fruit d’une diminution de la taille moyenne de cristallites et d’un confinement géométrique plus prononcé. En outre, l’augmentation de résistivité résulte également d’une élévation de la probabilité de réflexion des électrons aux joints de grains. Cette dernière a été associée à la réduction de la proportion de joints de grains spéciaux de cohérence atomique élevée. / The evolution of the microelectronic technology leads to a transistors integration density always stronger. The Damascene copper interconnections structures follow this tendency and must be controlled in terms of manufacturing, performance and robustness, these different aspects being intimately related to the residual stresses and resistivity. This thesis aims to understand the mechanisms of the residual stresses generation and identify the different contributions to the resistivity of these objects as a function of annealing conditions and dimensions (from about a hundred of nm to several µm). In order to do this, the respective effects of the microstructure and dimensions of electroplated copper films and lines were separated on the basis of analytical models integrating microstructural and geometrical parameters. The microstructure was principally analysed from mappings of crystalline orientations achieved by EBSD. For the copper lines of width 0.2 and 1 µm, the residual stresses were deduced from the exploitation of nano-rotating sensors specially elaborated. The results obtained show that independently of the annealing temperature, the resistivity and residual stresses increase observed toward the small dimensions arises from the diminution of the average crystallites size and the geometrical confinement more pronounced. Furthermore, the resistivity increase results also of the electrons reflection probability growth at grains boundaries. This last point was associated to the reduction of the proportion of special grains boundaries having a high atomic coherency.
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Development of Generic Communication Middleware for Embedded Sensor Systems Transmitting Health ParametersKailayanathan, Subaharan, Kamdod, Saji January 2020 (has links)
Health technology or e-Health is one of the most rapidly growing areas in healthcare today and it has been an important requirement as a new concept of healthcare industry. Since global society has been changed to aging society and the healthcare cost has been increasing in the 21st century since 2007. As the total number of people aged 65 or older is expected to increase from 12% to 22% in 2050 which is double the rate, and at the same time there is a decrease in in-fertility rates and increase in life expectancy due to the increase in life quality, there is a need to investigate the needs and requirements of an intelligent embedded sensor systems in health applications, and to develop a new communication protocol or set of protocols that can be used to send data collected from a hub within a house, home-care or a complex and send it securely and reliably to a central database where the gathered data can be monitored by a medical professional to make decisions for further interventions. The employed communication protocol should also be able to securely transmit confidential parameters from the hospital network to a central server outside of the hospital network. The final protocol must be inline with the regulations of the EU. This thesis is done in collaboration with Tjeders AB, Stille AB, and Embedded Sensor Systems for Health Plus (ESS-H+) research profile at Mälardalen University. In this thesis, different communication protocols such as IPSec and TLS and algorithms such as AES and RSA are examined and based on the requirements provided by the companies certain of these protocols and algorithms will be used in the final implementation. Different performance metrics such as overhead, round trip delay and throughput will be measured for the chosen communication protocols and recommendations will be given on which of the protocols and algorithms needs to be used to obtain an optimized, secure and reliable network.
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Exploring Great Basin National Park using a high-resolution Embedded Sensor NetworkSambuco, Emily Nicole 28 August 2019 (has links)
No description available.
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Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (esd) Protection StructuresSalcedo, Javier 01 January 2006 (has links)
The technology evolution and complexity of new circuit applications involve emerging reliability problems and even more sensitivity of integrated circuits (ICs) to electrostatic discharge (ESD)-induced damage. Regardless of the aggressive evolution in downscaling and subsequent improvement in applications' performance, ICs still should comply with minimum standards of ESD robustness in order to be commercially viable. Although the topic of ESD has received attention industry-wide, the design of robust protection structures and circuits remains challenging because ESD failure mechanisms continue to become more acute and design windows less flexible. The sensitivity of smaller devices, along with a limited understanding of the ESD phenomena and the resulting empirical approach to solving the problem have yielded time consuming, costly and unpredictable design procedures. As turnaround design cycles in new technologies continue to decrease, the traditional trial-and-error design strategy is no longer acceptable, and better analysis capabilities and a systematic design approach are essential to accomplish the increasingly difficult task of adequate ESD protection-circuit design. This dissertation presents a comprehensive design methodology for implementing custom on-chip ESD protection structures in different commercial technologies. First, the ESD topic in the semiconductor industry is revised, as well as ESD standards and commonly used schemes to provide ESD protection in ICs. The general ESD protection approaches are illustrated and discussed using different types of protection components and the concept of the ESD design window. The problem of implementing and assessing ESD protection structures is addressed next, starting from the general discussion of two design methods. The first ESD design method follows an experimental approach, in which design requirements are obtained via fabrication, testing and failure analysis. The second method consists of the technology computer aided design (TCAD)-assisted ESD protection design. This method incorporates numerical simulations in different stages of the ESD design process, and thus results in a more predictable and systematic ESD development strategy. Physical models considered in the device simulation are discussed and subsequently utilized in different ESD designs along this study. The implementation of new custom ESD protection devices and a further integration strategy based on the concept of the high-holding, low-voltage-trigger, silicon controlled rectifier (SCR) (HH-LVTSCR) is demonstrated for implementing ESD solutions in commercial low-voltage digital and mixed-signal applications developed using complementary metal oxide semiconductor (CMOS) and bipolar CMOS (BiCMOS) technologies. This ESD protection concept proposed in this study is also successfully incorporated for implementing a tailored ESD protection solution for an emerging CMOS-based embedded MicroElectroMechanical (MEMS) sensor system-on-a-chip (SoC) technology. Circuit applications that are required to operate at relatively large input/output (I/O) voltage, above/below the VDD/VSS core circuit power supply, introduce further complications in the development and integration of ESD protection solutions. In these applications, the I/O operating voltage can extend over one order of magnitude larger than the safe operating voltage established in advanced technologies, while the IC is also required to comply with stringent ESD robustness requirements. A practical TCAD methodology based on a process- and device- simulation is demonstrated for assessment of the device physics, and subsequent design and implementation of custom P1N1-P2N2 and coupled P1N1-P2N2//N2P3-N3P1 silicon controlled rectifier (SCR)-type devices for ESD protection in different circuit applications, including those applications operating at I/O voltage considerably above/below the VDD/VSS. Results from the TCAD simulations are compared with measurements and used for developing technology- and circuit-adapted protection structures, capable of blocking large voltages and providing versatile dual-polarity symmetric/asymmetric S-type current-voltage characteristics for high ESD protection. The design guidelines introduced in this dissertation are used to optimize and extend the ESD protection capability in existing CMOS/BiCMOS technologies, by implementing smaller and more robust single- or dual-polarity ESD protection structures within the flexibility provided in the specific fabrication process. The ESD design methodologies and characteristics of the developed protection devices are demonstrated via ESD measurements obtained from fabricated stand-alone devices and on-chip ESD protections. The superior ESD protection performance of the devices developed in this study is also successfully verified in IC applications where the standard ESD protection approaches are not suitable to meet the stringent area constraint and performance requirement.
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Conception, réalisation de capteurs non-invasifs ambulatoires et d'exocapteurs embarqués pour l'étude et le suivi de la réactivité émotionnelle / Design and development of non-invasive, ambulatory or embedded sensors for the monitoring and the study of emotional reactivityMassot, Bertrand 12 December 2011 (has links)
Le suivi de l'état de santé et de la réactivité émotionnelle chez l'individu est au cœur de la médecine de demain ; il participe notamment au développement de nouveaux services de soins en santé tels que la médecine à domicile, la médecine mobile ou encore la médecine personnalisée. Cependant il nécessite d'une part la définition d'indicateurs adaptés à la mesure en environnement complexe, et d'autre part la conception d'exocapteurs et d'instrumentations intégrés dans l'environnement de l'individu. Les travaux de cette thèse présentent la démarche nécessaire au passage de mesures physiologiques en laboratoire à celles des conditions de la vie de tous les jours, en s'articulant autour de deux axes d'étude : Le premier axe concerne la conception et le développement d'une instrumentation ambulatoire pour la mesure de paramètres physiologiques en conditions écologiques. Le système portable EmoSense conçu pour la mesure de la fréquence cardiaque, de la résistance cutanée et de la température cutanée permet l'identification de nouveaux indicateurs de la réactivité émotionnelle à partir de mesures réalisées en situations réelles. L'expérimentation présentée sur l'objectivation du stress chez les personnes aveugles pendant leur déplacement en milieu urbain a permis la construction d'un nouvel indicateur pour l'analyse de l'activité électrodermale. Par ailleurs, cette démarche met en avant l'importance de la mise en place de plateformes ayant pour objectif de fournir un support pour l'expérimentation en conditions écologiques, telles que les Living Lab. La seconde partie des travaux est consacrée à la mesure de l'activité électrodermale (résistance électrique cutanée) pendant la conduite de véhicule. Cette mesure est basée sur la conception et le développement d'un volant instrumenté. Ce travail illustre les difficultés technologiques liées à la mesure de signaux bioélectriques par exocapteurs pour leur intégration dans l'environnement de l'individu. Nous proposons ainsi une topologie innovante de placement des électrodes dans le but d'optimiser les facteurs de disponibilité et de robustesse du signal liés à la mesure de signaux bioélectriques par exocapteurs. / Improvement in quality and efficiency of health and medicine, at home and in hospital, has become of paramount importance. The solution to this problem would require the continuous monitoring of several key patient parameters, including emotional reactivity analysis, in order to assist the development of mobile Health or personalized Health. But it often requires a new definition of commonly used indicators to adapt them for an in situ monitoring, and also the design of exo-sensors and instrumentations integrated in the environment. This PhD work contributes to the definition of the steps leading experiments from laboratory to real-life conditions: First a new ambulatory device was developed to enable the measurement of heart rate, electrodermal activity and skin temperature during in situ experiments, for the definition of new indicators of emotional reactivity. Experimenting in real-life settings has led to the definition of a novel, more pertinent parameter for the evaluation of stress in the blind when walking in urban space.These results were very encouraging for the use of such ambulatory devices for experiments under real-life conditions, such as Living Labs. The second part deals with the assessment of electrodermal activity while driving. This work is based on the design and the development of a steering wheel enabling the measurement of galvanic skin resistance. This has shown the challenges and issues of the assessment of bioelectric signals with exo-sensors for their integration in the human environment. Therefore we propose a new and innovative topology of electrodes on the steering wheel, for the optimization of the amount of available data and the quality of biolectric signals.
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