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Jouni, Ali. "Space radiation effects on CMOS single photon avalanche diodes (SPADs)." Electronic Thesis or Diss., Toulouse, ISAE, 2024. http://www.theses.fr/2024ESAE0012.
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Le sujet de cette thèse traite des effets des radiations spatiales sur des détecteurs CMOS à avalanches, et particulièrement sur les dispositifs SPADs (pour Single Photon Avalanche Diode en anglais, ou photodiode à avalanche à photon unique). Ces photodiodes présentent un gain interne presque infini et sont donc sensibles à des très faibles conditions de lumières. Ainsi, avec en plus une excellente résolution temporelle, ces capteurs peuvent être très intéressant pour des applications spatiales nécessitant des mesures de temps de vols, comme la topographie d’objets célestes ou les Rendez-vous spatiaux. Cependant, l’espace est un environnement hostile du fait des radiations provenant du Soleil, des particules piégées dans la magnétosphère terrestre ainsi qu’au-delà du système solaire. De ce fait, dans le cadre de ces travaux de thèse, un modèle est mis en place pour prédire la dégradation du courant d’obscurité des SPADs, le Dark Count Rate (DCR), après des irradiations aux protons. Expérimentalement, deux technologies de matrices de SPADs sont irradiées avec des protons, des rayons X et des rayons γ. De ce fait, les effets ionisants et non-ionisants sont investigués pour ces capteurs à avalanches, et des différences en comparaison avec les pixelsdes capteurs d’images standard sont soulignées. Ensuite, les caractéristiques des défauts induits par la création d’états d’interface entre les oxides et le silicium et les dommages de déplacement atomique dans le substrat sont examinées, avec notamment la présence de comportement RTS (Random Telegraph Signal). Enfin, l’identification de la nature de ces défauts est réalisée par l’intermédiaire de recuits isochrones après l’expositions des matrices de SPADs aux trois différentes radiations mentionnées au-dessusThe subject of this thesis deals with the effects of space radiation on CMOS avalanche detectors, particularly on Single Photon Avalanche Diodes (SPADs). These photodiodes exhibit nearly infinite internal gain and are therefore sensitive to very low light conditions. Thus, with excellent temporal resolution, these sensors can be very interesting for space applications requiring time-of-flight measurements, such as the topography of celestial objects or space Rendezvous. However, space is a hostile environment due to radiation from the Sun, particles trapped in the Earth’s magnetosphere, and beyond the solar system. Consequently, within the framework of this thesis work, a model is established to predict thedegradation of the dark current of SPADs, the Dark Count Rate (DCR), after proton irradiations. Experimentally, two SPAD array technologies are irradiated with protons, X-rays, and γ rays. Hence, ionizing and non-ionizing effects are investigated for these avalanche sensors, and differences compared to pixels of standard image sensors are highlighted. Subsequently, the characteristics of defects induced by the creation of interface traps between oxides and silicon and atomic displacement damage in the substrate are examined, including the presence of Random Telegraph Signal (RTS) behaviors. Finally, the nature of these defects is identified through isochronal annealing after irradiations of the SPAD arrays using the three different radiation types mentioned above
2
Kim, Young-Seog. "Damage structures and fault evolution around strike-slip faults." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340659.
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Tappin, David Keith. "The characterisation of displacement cascades in austenitic Fe-Cr-Ni alloys." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317254.
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Sutton, Akil K. "Displacement Damage and Ionization Effects in Advanced Silicon-Germanium Heterojunction Bipolar Transistors." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7217.
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A summary of total dose effects observe in advanced Silicon Germanium (SiGe) Heterojunction Bipolar Transistors (HBTs) is presented in this work. The principal driving froces behin the increased use of SiGe BiCMOS technology in space based electronics systems are outlined in the motivation Section of Chapter I. This is followed by a discussion of the strained layer Si/SiGe material structure and relevant fabrication techniques used in the development of the first generation of this technology. A comprehensive description of the device performance is presented.
Chapter II presents an overview of radiation physics as it applies to microelectronic devices. Several sources of radiation are discussed including the environments encountered by satellites in different orbital paths around the earth. The particle types, interaction mechanisms and damage nomenclature are described.
Proton irradiation experiments to analyze worst case displacement and ionization damage are examined in chapter III. A description of the test conditions is first presented, followed by the experimental results on the observed dc and ac transistor performance metrics with incident radiation. The impact of the collector doping level on the degradation is discussed.
In a similar fashion, gamma irradiation experiments to focus on ionization only effects are presented in chapter IV. The experimental design and dc results are first presented, followed by a comparison of degradation under proton irradiation. Additional proton dose rate experiments conducted to further investigate observed differences between proton and gamma results are presented.
5
Khorsandi, Behrooz. "Modeling of displacement damage in silicon carbide detectors resulting from neutron irradiation." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1173103438.
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CAMBIAGGI, LUDOVICA. "Damage assessment of churches exposed to slope displacements in sliding areas." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/1029444.
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Protecting cultural heritage from water-soil interaction related threats is a current issue and the prediction of the effects of slope displacements on buildings is very challenging. The achievement of this goal is not straightforward since it usually requires high costs due to the great amount of data to be collected for setting up reliable forecasting models. Among these threats, slow moving landslides are considered in this research, because also small slope movements can seriously affect existing structures and cause damages. In this regard, the aim is to develop a simple but effective procedure to correlate the potential damage caused to soil displacements to the slope safety conditions, represented by an “intensity parameter” such as the slope safety factor. Churches located in, or close to, landslide areas, have been chosen as exposed structures: this choice makes the theme more challenging for the structural and geometric complexities of these particular historic buildings. Furthermore, while modelling and estimating the effects induced by deep excavations or tunnelling on existing buildings are known and widely treated geotechnical problems, the assessment of the damage caused by landslide movement has not been fully developed and only limited material exists in the literature.
The procedure developed and proposed in the Thesis takes into account:
i) identification and characterization of the exposed elements;
ii) assessment of displacements and associated strain level components caused by slope movement via numerical analyses;
iii) iii) proposal and assessment of an intensity parameter representative of deformations and stability conditions;
iv) iv) assessment of damage severity levels and develop of fragility curves,
v) v) validation of the proposed approach.
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McKenna, Alice J. "Ab initio and molecular dynamic models of displacement damage in crystalline and turbostratic graphite." Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/809906/.
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One of the functions of graphite is as a moderator in several nuclear reactor designs, including the Advanced Gas-cooled Reactor (AGR). In the reactor graphite is used to thermalise the neutrons produced in the fission reaction thus allowing a self-sustained reaction to occur. The graphite blocks, acting as the moderator, are constantly irradiated and consequently suffer damage. This thesis examines the types of damage caused using molecular dynamic (MD) simulations and ab intio calculations. Neutron damage starts with a primary knock-on atom (PKA), which is travelling so fast that it creates damage through electronic and thermal excitation (this is addressed with thermal spike simulations). When the PKA has lost energy the subsequent cascade is based on ballistic atomic displacement. These two types of simulations were performed on single crystal graphite and other carbon structures such as diamond and amorphous carbon as a comparison. The thermal spike in single crystal graphite produced results which varied from no defects to a small number of permanent defects in the structure. It is only at the high energy range that more damage is seen but these energies are less likely to occur in the nuclear reactor. The thermal spike does not create damage but it is possible that it can heal damaged sections of the graphite, which can be demonstrated with the motion of the defects when a thermal spike is applied. The cascade simulations create more damage than the thermal spike even though less energy is applied to the system. A new damage function is found with a threshold region that varies with the square root of energy in excess of the energy threshold. This is further broken down in to contributions from primary and subsequent knock-on atoms. The threshold displacement energy (TDE) is found to be Ed=25eV at 300K. In both these types of simulation graphite acts very differently to the other carbon structures. There are two types of polycrystalline graphite structures which simulations have been performed on. The difference between the two is at the grain boundaries with one having dangling bonds and the other one being bonded. The cascade showed the grain boundaries acting as a trap for the knock-on atoms which produces more damage compared with the single crystal. Finally the effects of turbostratic disorder on damage is considered. Density functional theory (DFT) was used to look at interstitials in (002) twist boundaries and how they act compared to AB stacked graphite. The results of these calculations show that the spiro interstitial is more stable in these grain boundaries, so at temperatures where the interstitial can migrate along the c direction they will segregate to (002) twist boundaries.
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CONSOLANDI, CRISTINA. "Displacement damage induced by cosmic rays in silicon devices using geant4 toolkit for space applications." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/7870.
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In the space environment the dominant radiation at energies above 50 MeV/nucleon is constituted by the Galactic Cosmic Rays (GCRs) which are capable to inflict permanent damage to silicon devices.
In particular the displacement damage was analyzed and the
Non-Ionizing Energy Loss (NIEL) was calculated both at high and low energies in order to estimate the displacement damage for the entire energy range of the space radiation environment. Of particular relevance was the development of an improved implementation of the Geant4 single scattering model. This modification gives the possibility to calculate the Coulomb scattering contribution to the NIEL for heavy nuclei at high energies. Moreover the GCR fluxes of the ISO model 15390 was introduced in Geant4 as a particle generator in order to reproduce the solar modulation effect on GCRs. For instance, using the ISO model of GCRs fluxes and the NIEL for all the nuclei, we estimated the expected NIEL-Dose absorbed by a silicon sample during one year mission.
In addition Hall effect measurements were performed in our laboratory on silicon samples of different resistivities which are usually used as substrates for the fabrication of devices employed in space missions
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Gerstel, Markus. "Radiation damage in protein crystallography : susceptibility study." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:be55baee-19b7-4a34-8694-fb9c3606a19c.
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Protein structure models obtained from X-ray crystallography are subject to radiation damage. The resulting specific alterations to protein structures can be mistaken for biological features, or may obscure actual protein mechanisms, leading to misidentification or obscuration of biological insight. The radiation chemistry behind this site-specific damage is not well understood. Radiation damage processes progress in proportion to the dose absorbed by the crystal in the diffraction experiment. Doses can be estimated using existing software, but these assume idealised experimental conditions. To simulate complex diffraction experiments, including treatment of imperfect X-ray beam profiles and inhomogeneous dose distributions, a new program, RADDOSE-3D, was developed. RADDOSE-3D can be integrated into beamline software to provide convenient, more accurate, comparative, and publishable dose figures, also facilitating informed data collection decisions. There is currently no method to automatically detect specific radiation damage in protein structure models in the absence of an 'undamaged' reference model. Radiation damage research therefore generally relies on detailed observation of a few model proteins. A new metric, BDamage, is designed and used to identify and quantify specific radiation damage in the first large-scale statistical survey of 2,704 published protein models, which are examined for the effects of local environments on site-specific radiation damage susceptibility. A significant positive correlation between susceptibility and solvent accessibility is identified. Current understanding of radiation damage progression is mostly based on a few consecutive structure model 'snapshots' at coarse dose intervals. The low sampling rate considerably limits the ability to identify varying site susceptibility and its causes. Real space electron density data are obtained for crystals of different mutants of a RhoGDI protein with very high sequence identity, to determine sensitising and stabilising factors for radiation induced structural changes. Utilising a newly developed data collection and analysis protocol, these changes could be tracked with unprecedented time resolution.
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Rauch, Alan F. "EPOLLS: An Empirical Method for Prediciting Surface Displacements Due to Liquefaction-Induced Lateral Spreading in Earthquakes." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30346.
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In historical, large-magnitude earthquakes, lateral spreading has been a very damaging type of ground failure. When a subsurface soil deposit liquefies, intact blocks of surficial soil can move downslope, or toward a vertical free face, even when the ground surface is nearly level. A lateral spread is defined as the mostly horizontal movement of gently sloping ground (less than 5% surface slope) due to elevated pore pressures or liquefaction in undelying, saturated soils. Here, lateral spreading is defined specifically to exclude liquefaction failures of steeper embankments and retaining walls, which can also produce lateral surface deformations. Lateral spreads commonly occur at waterfront sites underlain by saturated, recent sediments and are particularly threatening to buried utilities and transportation networks. While the occurrence of soil liquefaction and lateral spreading can be predicted at a given site, methods are needed to estimate the magnitude of the resulting deformations.
In this research effort, an empirical model was developed for predicting horizontal and vertical surface displacements due to liquefaction-induced lateral spreading. The resulting model is called "EPOLLS" for Empirical Prediction Of Liquefaction-induced Lateral Spreading. Multiple linear regression analyses were used to develop model equations from a compiled database of historical lateral spreads. The complete EPOLLS model is comprised of four components: (1) Regional-EPOLLS for predicting horizontal displacements based on the seismic source and local severity of shaking, (2) Site-EPOLLS for improved predictions with the addition of data on the site topography, (3) Geotechnical-EPOLLS using additional data from soil borings at the site, and (4) Vertical-EPOLLS for predicting vertical displacements. The EPOLLS model is useful in phased liquefaction risk studies: starting with regional risk assessments and minimal site information, more precise predictions of displacements can be made with the addition of detailed site-specific data. In each component of the EPOLLS model, equations are given for predicting the average and standard deviation of displacements. Maximum displacements can be estimated using probabilities and the gamma distribution for horizontal displacements or the normal distribution for vertical displacements.Ph. D.
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Walldén, Johan. "Radiation Induced Effects in Electronic Devices and Radiation Hardening By Design Techniques." Thesis, Linköpings universitet, Elektroniska komponenter, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-109343.
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The aim with this thesis has been to make a survey of radiation hardened electronics, explaining why and how radiation affects electronics and what can be done to harden it. The effects radiation have on electronics in general and in specific commonly used devices are explained qualitatively. The effects are divided into Displacement Damage (DD), Total Ionizing Dose (TID) and Single Event Effects (SEEs). The devices explained are MOSFETs, Silicon On Insulator (SOI) transistors, 3D-transistors, Power transistors, Optocouplers, Field Programmable Gate Arrays (FPGAs), three dimensional circuits (3D-ICs) and Flash memories. Different radiation hardening by design (RHBD) techniques used to reduce or to remove the negative effects radiation induces in electronics are also explained. The techniques are Annular transistors, Enclosed source/drain transistors, Guard rings, Triple Modular Redundancy (TMR), Dual Interlocked Storage Cells (DICE), Guard gates, Temporal filtering,Multiple drive, Charge dissipation, Differential Charge Cancellation (DCC), Scrubbing, Lockstep, EDAC codes and Watchdog timers.
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Singh-Levett, Ishan. "Real-time integral based structural health monitoring." Thesis, University of Canterbury. Mechanical Engineering, 2006. http://hdl.handle.net/10092/1171.
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Structural Health Monitoring (SHM) is a means of identifying damage from the structural response to environmental loads. Real-time SHM offers rapid assessment of structural safety by owners and civil defense authorities enabling more optimal response to major events. This research presents an real-time, convex, integral-based SHM methods for seismic events that use only acceleration measurements and infrequently measured displacements, and a non-linear baseline model including hysteretic dynamics and permanent deformation. The method thus identifies time-varying pre-yield and post-yield stiffness, elastic and plastic components of displacement and final residual displacement. For a linear baseline model it identifies only timevarying stiffness. Thus, the algorithm identifies all key measures of structural damage affecting the immediate safety or use of the structure, and the long-term cost of repair and retrofit. The algorithm is tested with simulated and measured El Centro earthquake response data from a four storey non-linear steel frame structure and simulated data from a two storey non-linear hybrid rocking structure. The steel frame and rocking structures exhibit contrasting dynamic response and are thus used to highlight the impact of baseline model selection in SHM. In simulation, the algorithm identifies stiffness to within 3.5% with 90% confidence, and permanent displacement to within 7.5% with 90% confidence. Using measured data for the frame structure, the algorithm identifies final residual deformation to within 1.5% and identifies realistic stiffness values in comparison to values predicted from pushover analysis. For the rocking structure, the algorithm accurately identifies the different regimes of motion and linear stiffness comparable to estimates from previous research. Overall, the method is seen to be accurate, effective and realtime capable, with the non-linear baseline model more accurately identifying damage in both of the disparate structures examined.
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Yilmaz, Taner. "Seismic Response Of Multi-span Highway Bridges With Two-column Reinforced Concrete Bents Including Foundation And Column Flexibility." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610191/index.pdf.
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Seismic design of highway bridges has improved as a result of the experience gained from large earthquakes of the last thirty years. Ductility demand and reserved capacity are extremely important response measures used in new bridge designs to assess target damage levels. However, the application of practical design approaches specified in bridge design codes is not well-defined for bridges over flexible foundations. Within the scope of this research, thirty two bridge models having varying column aspect ratio, amount of column longitudinal reinforcement and foundation flexibility parameters are investigated through a series of analyses such as response spectrum analysis and inelastic time-history analysis under &ldquosafety evaluation earthquake&rdquo
hazard level with a return period of 1000 years, and push-over analysis. Using the results of analyses, seismic response of the investigated bridges are identified with several measures such as displacement capacity over demand ratio, global displacement ductility demand, and response modification factor, along with maximum concrete and steel strains of columns. A correlation between concrete and steel strains and seismic response measure values is constructed to estimate damage levels with commonly used response measures. The findings of this research revealed that global displacement ductility demand is not a favorable response measure for assessing damage levels. On the other hand, displacement capacity over demand ratios can be suggested for estimation of damage levels especially where foundation flexibility effects are extensive as system yielding is not taken into consideration.
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Palmer, Logan Matthew. "Development of a Simplified Analysis Approach for Predicting Pile Deflections of Piers Subjected to Lateral Spread Displacements and Application to a Pier Damaged During the 2010 Maule, Chile, M8.8 Earthquake." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7045.
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The 2010, moment magnitude 8.8 earthquake that occurred near Maule, Chile caused major damages to several piers in the Port of Coronel located approximately 160 kilometers (100 miles) to the South of the earthquake epicenter. One of the piers, the North Pier, experienced significant lateral spreading that was caused from liquefaction of the soils at the approach zone of the pier. Damages from lateral spreading and liquefaction effects consisted of sheet pile welding ruptures of the cross-support beams, stiffener buckling, pile displacements, pile rotations, and pier deck displacement. Researchers analyzed the North Pier after the earthquake and documented in detail the damage caused by lateral spread displacements. This study introduces a simplified performance-based procedure called the "Simplified Modeling Procedure" that is used for the analysis of piles supporting a pier that are exposed to lateral spread displacements. The procedure uses the software LPILE, a common program for analyzing a single pile under lateral loading conditions, to evaluate a more complex multi-pile pier design. Instead of analyzing each of the piles in a given pier individually, the procedure utilizes what is known as a "Super Pile" approach to combine several piles into a single representative pile during the analysis. To ensure displacement compatibility between each "Super Pile" in the analysis, the "Super Piles" are assumed to be fully connected at the top of each "Super Pile" to the pier deck. The Simplified Modeling Procedure is developed and tested using the case study history of the North Pier from the Port of Coronel during the 2010 Maule earthquake. The Simplified Modeling Procedure incorporates p-y springs with a lateral push-over analysis. This approach allows the analysis to be performed in a matter of seconds and allows the user to more easily draw the needed correlations between the rows of piles. This procedure helps identify that different rows of piles either contribute to the movement of the pier or contribute to the bracing of the pier. The procedure ultimately predicts the anticipated pier deck deflection by determining when all the pile rows and their respective shear forces are in equilibrium. The Simplified Modeling Procedure predicted that the North Pier experienced deflections between approximately 0.31 meters (1.01 feet) and 0.38 meters (1.26 feet). The predicted deflections and rotations determined using the procedure were determined to be a relatively close representation of the observations made during the post-earthquake reconnaissance observations.
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Kulisek, Jonathan Andrew. "The Effects of Nuclear Radiation on Schottky Power Diodes and Power MOSFETs." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1267502877.
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Ursule, Marie-Cécile. "Compréhension des mécanismes physiques à l'origine des dégradations électriques extrêmes des pixels dans les capteurs d'images irradiés." Thesis, Toulouse, ISAE, 2017. http://www.theses.fr/2017ESAE0014/document.
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Les capteurs d'images sont utilisés dans diverses applications spatiales : observation spatiale, calcul d'attitude etc. Ces capteurs évoluent dans l’environnement spatial dont les rayonnements entraînent une dégradation de leurs performances. Parmi les paramètres impactés, nous nous intéressons au courant d'obscurité des pixels. Ce courant parasite correspond à la génération de porteurs de charges sans lumière par simple excitation thermique, induisant l'augmentation du bruit de fond des images. Les pixels fortement dégradés sont particulièrement pénalisants pour les missions spatiales. Cet effet pousse donc la communauté spatiale à développer des méthodes de prédiction performantes. L'ONERA a développé une méthode originale de prédiction des courants d'obscurité basée sur la méthode de Monte Carlo et la librairie GEANT4. L’objectif de la thèse est d’améliorer la prédiction de l’outil. Dans un premier temps, nous avons modifié l'outil numérique pour des cas extrêmes de modélisations pour lesquels les modélisations Monte Carlo sont trop longues. Pour cela, nous avons développé des méthodes utilisant des simplifications statistiques. Dans un second temps, nous avons étudié l’influence de la géométrie du pixel sur le courant d'obscurité. L’idée est de suivre les cascades de dégradations générées par les particules spatiales et de déterminer si ces cascades restent confinées au sein du pixel impacté ou si elles se propagent dans les pixels voisins. Enfin, nous avons élaboré dans notre outil un modèle simulant les mécanismes liés au champ électrique potentiellement responsables des dégradations les plus élevées, les effets Poole-Frenkel et tunnel assisté par phononsImage sensors are used in various space applications: space and earth observations, attitude calculation etc. Those sensors are very sensitive to the space environment whose radiations lead to a degradation of their performances. Among the different impacted parameters, we are interested in the increase of dark current in the pixels. This parasitic current is caused by the thermal generation of charge carriers without any light excitation inducing the increase of the background noise on the images. Some pixels exhibiting the highest degradation are particularly disadvantageous for space missions. They can be critical for some missions and impose to the space community to develop effective prediction methods. ONERA developed an original method to predict dark current induce by the space radiations, based on a Monte Carlo method and the GEANT4 library. The objective of the PhD is to improve the performances of the tool. The approach of this work is first to modify the numerical tool for extreme cases of modelling (i.e. high fluencies or huge pixel volume) for which the Monte Carlo simulations are too long. In order to reduce this computation time, we developed calculation methods using statistical simplifications. In a second part, we studied the influence of the pixel geometry on the dark current. The idea is to follow the degradation cascades created by space particles and to determine if those cascades are contained in the impacted pixel or if they reach neighbor pixels. Finally, we modelled in our tool the physical mechanisms potentially responsible of the highest degradations linked to the electric field, the Poole-Frenkel effect and the phonon assisted tunneling
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Virmontois, Cédric. "Analyse des effets des déplacements atomiques induits par l’environnement radiatif spatial sur la conception des imageurs CMOS." Thesis, Toulouse, ISAE, 2012. http://www.theses.fr/2012ESAE0009/document.
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L' imagerie spatiale est aujourd'hui un outil indispensable au développement durable, à la recherche et aux innovations scientifiques ainsi qu’à la sécurité et la défense. Fort de ses excellentes performances électro-optiques, de son fort taux d’intégration et de la faible puissance nécessaire à son fonctionnement, le capteur d’images CMOS apparait comme un candidat sérieux pour ce type d’application. Cependant, cette technologie d’imageur doit être capable de résister à l’environnement radiatif spatial hostile pouvant dégrader les performances des composants électroniques. Un nombre important d’études précédentes sont consacrées à l’impact des effets ionisants sur les imageurs CMOS, montrant leur robustesse et des voies de durcissement face à de telles radiations. Les conclusions de ces travaux soulignent l’importance d’étudier les effets non-ionisants, devenant prépondérant dans les imageurs utilisant les dernières évolutions de la technologie CMOS. Par conséquent, l’objectif de ces travaux de thèse est d’étudier l’impact des effets non-ionisants sur les imageurs CMOS. Ces effets, regroupés sous le nom de déplacements atomiques, sont étudiés sur un nombre important de capteurs d’images CMOS et de structures de test. Ces dispositifs sont conçus avec des procédés de fabrication CMOS différents et en utilisant des variations de règle de dessin afin d’investiguer des tendances de dégradation commune à la technologie d’imager CMOS. Dans ces travaux, une équivalence entre les irradiations aux protons et aux neutrons est mise en évidence grâce à des caractéristiques courant-tension et des mesures de spectroscopie transitoire de niveau profond. Ces résultats soulignent la pertinence des irradiations aux neutrons pour étudier les effets non-ionisants. L’augmentation et la déformation de l’histogramme de courant d’obscurité ainsi que le signal télégraphique aléatoire associé, qui devient le facteur limitant des futures applications d’imagerie spatiale, sont évalué et modélisés. Des paramètres génériques d’évaluation des effets des déplacements atomiques sont mis en évidence, permettant de prévoir le comportement des capteurs d’images CMOS en environnement radiatif spatial. Enfin, des méthodes d’atténuation et des voies de durcissement des imageurs CMOS limitant l’impact des déplacements atomiques sont proposéesToday, space imaging is an essential tool for sustainable development, research and scientific innovation as well as security and defense. Thanks to their good electro-optic performances and low power consumption, CMOS image sensors are serious candidates to equip future space instruments. However, it is important to know and understand the behavior of this imager technology when it faces the space radiation environment which could damage devices performances. Many previous studies have been focused on ionizing effects in CMOS imagers, showing their hardness and several hardening-by-design techniques against such radiations. The conclusions of these works emphasized the need to study non-ionizing effects which have become a major issue in the last generation of CMOS image sensors. Therefore, this research work focuses on non-ionizing effects in CMOS image sensors. These effects, also called displacement damage, are investigated on a large number of CMOS imagers and test structures. These devices are designed using several CMOS processes and using design rule changes in order to observe possible common behaviors in CMOS technology. Similarities have been shown between proton and neutron irradiations using current-voltage characteristics and deep level transient spectroscopy. These results emphasize the relevance of neutron irradiations for an accurate study of the non-ionizing effects. Then, displacement damage induced dark current increase as well as the associated random telegraph signal are measured and modeled. Common evaluation parameters to investigate displacement damage are found, allowing imager behavior prediction in space radiation environment. Finally, specific methods and hardening-by-design techniques to mitigate displacement damage are proposed
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Nayyerloo, Mostafa. "Real-time Structural Health Monitoring of Nonlinear Hysteretic Structures." Thesis, University of Canterbury. Department of Mechanical Engineering, 2011. http://hdl.handle.net/10092/6581.
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The great social and economic impact of earthquakes has made necessary the development of novel structural health monitoring (SHM) solutions for increasing the level of structural safety and assessment. SHM is the process of comparing the current state of a structure’s condition relative to a healthy baseline state to detect the existence, location, and degree of likely damage during or after a damaging input, such as an earthquake. Many SHM algorithms have been proposed in the literature. However, a large majority of these algorithms cannot be implemented in real time. Therefore, their results would not be available during or immediately after a major event for urgent post-event response and decision making. Further, these off-line techniques are not capable of providing the input information required for structural control systems for damage mitigation. The small number of real-time SHM (RT-SHM) methods proposed in the past, resolve these issues. However, these approaches have significant computational complexity and typically do not manage nonlinear cases directly associated with relevant damage metrics. Finally, many available SHM methods require full structural response measurement, including velocities and displacements, which are typically difficult to measure. All these issues make implementation of many existing SHM algorithms very difficult if not impossible.
This thesis proposes simpler, more suitable algorithms utilising a nonlinear Bouc-Wen hysteretic baseline model for RT-SHM of a large class of nonlinear hysteretic structures. The RT-SHM algorithms are devised so that they can accommodate different levels of the availability of design data or measured structural responses, and therefore, are applicable to both existing and new structures. The second focus of the thesis is on developing a high-speed, high-resolution, seismic structural displacement measurement sensor to enable these methods and many other SHM approaches by using line-scan cameras as a low-cost and powerful means of measuring structural displacements at high sampling rates and high resolution. Overall, the results presented are thus significant steps towards developing smart, damage-free structures and providing more reliable information for post-event decision making.
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Hardie, Christopher David. "Micro-mechanics of irradiated Fe-Cr alloys for fusion reactors." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:a3ac36ba-ca6f-4129-8f37-f1278ef8a559.
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In the absence of a fusion neutron source, research on the structural integrity of materials in the fusion environment relies on current fission data and simulation methods. Through investigation of the Fe-Cr system, this detailed study explores the challenges and limitations in the use of currently available radiation sources for fusion materials research. An investigation of ion-irradiated Fe12%Cr using nanoindentation with a cube corner, Berkovich and spherical tip, and micro-cantilever testing with two different geometries, highlighted that the measurement of irradiation hardening was largely dependent on the type of test used. Selected methods were used for the comparison of Fe6%Cr irradiated by ions and neutrons to a dose of 1.7dpa at a temperature of 288°C. Micro-cantilever tests of the Fe6%Cr alloy with beam depths of 400 to 7000nm, identified that size effects may significantly obscure irradiation hardening and that these effects are dependent on radiation conditions. Irradiation hardening in the neutron-irradiated alloy was approximately double that of the ion-irradiated alloy and exhibited increased work hardening. Similar differences in hardening were observed in an Fe5%Cr alloy after ion-irradiation to a dose of 0.6dpa at 400°C and doses rates of 6 x 10-4dpa/s and 3 x 10-5dpa/s. Identified by APT, it was shown that increased irradiation hardening was likely to be caused by the enhanced segregation of Cr observed in the alloy irradiated with the lower dose rate. These observations have significant implications for future fusion materials research in terms of the simulation of fusion relevant radiation conditions and micro-mechanical testing.
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Cai, Yinfei. "Simulation des affaissements miniers et de leurs conséquences sur le bâti." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0010/document.
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L’objectif de cette thèse est, d’une part, de proposer une amélioration des méthodes d’estimation des cuvettes d’affaissement et des méthodes d’évaluation des dommages susceptibles de se produire sous leurs effets et de l’autre, de développer des outils basés sur ces méthodes pour étudier les affaissements et les dommages sur des cas pratiques. L’étude de l'influence de la topographie sur les cuvettes d'affaissement dans des conditions d’exploitation simplifiées grâce à des modèles numériques avec des profondeurs d'exploitation et des pentes du sol variables a permis de proposer une nouvelle fonction d’influence basée sur une densité de probabilité normale asymétrique lorsque la surface du sol est non-plane. Une modélisation simplifiée des habitations en maçonnerie sous la forme de deux modèles de structures bidimensionnels croisés, alignés avec les axes d’inertie de la structure étudiée et dans lesquels la méthode des déplacements est mise en œuvre pour calculer les efforts internes et les déformations sous l’effet de déplacements imposées des fondations. Ces modèles simplifiés dont les caractéristiques géométriques et mécaniques sont définis pour chaque type de bâtiment étudié permettent d’estimer les efforts appliqués à chaque bâtiment d’une ville exposée à un affaissement de terrain et de fournir de nouveaux critères d’évaluation des dommages prenant en compte davantage d’informations que les méthodes habituelles. Une estimation des dommages dans la ville de Joeuf sur la base des nouvelles méthodes proposées, tant pour le calcul de l’affaissement que pour l’estimation des dommages, a été réaliséeThe objective of this thesis is to improve the methods of subsidence computation and building damage evaluation, and to develop some tools based on these methods to study the mining subsidence and building damage cases in Lorraine. By investigating the topography influence on subsidence under simplified mining conditions, and using numerical models with varying mining depths and ground surface angles, a new influence function method, which is based on a probability density function of a skew normal distribution, to simulate the element subsidence, was firstly developed and can be used to compute the mining subsidence caused by the excavation under non-flat surface. Then, plane framed structural models were chosen to study the mechanical behavior of 3D buildings. For each building, two plane models located in the vertical sections passing through the principle inertia axes of the building’s projective polygon were considered. Their geometry and mechanical characteristics were chosen according to the construction type and used materials of the building under consideration. Then, by using the matrix displacement method with some modifications, the internal forces and displacements for the entire structure could be computed. The achieved internal forces could then be compared to damage grade criteria to determine the extent of building damage.Finally, by using the improved methods of subsidence computation and building damage evaluation, a real case application was performed in Joeuf city (France). The subsidence was computed and applied to the defined structural models as support displacements, and then the damage extents of the buildings in Joeuf were predicted
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Ferraro, Rudy. "Development of Test Methods for the Qualification of Electronic Components and Systems Adapted to High-Energy Accelerator Radiation Environments." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS118.
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Le Grand collisionneur de hadrons (LHC), le plus grand et le plus puissant au monde, a démarré en 2008 et constitue la dernière étape du complexe des accélérateurs du CERN. Le LHC consiste en un anneau de 27 kilomètres d'aimants supraconducteurs permettant d'accélérer deux faisceaux jusqu'à 7 TeV avant de les faire entrer en collision à 14 TeV dans l'une des cinq expériences de contrôle du résultat de la collision. Le LHC a notamment permis la découverte du boson de Higgs et d'autres particules baryoniques prédites par le modèle standard. L'environnement de rayonnement du LHC et de ses lignes d'injection est composé de différentes particules sur un large spectre d'énergies, du niveau GeV jusqu'au niveau meV (par exemple le neutron thermique). L'équipement électronique fonctionnant dans un environnement de rayonnement aussi rude, principalement basé sur des composants commerciaux prêts à l'emploi (COTS), peut subir des défaillances induites par des effets de rayonnement. La criticité de l'équipement peut être très élevée, dans le meilleur des cas, la défaillance d'un système de contrôle peut conduire à une chute du faisceau, ce qui peut drastiquement rendre le faisceau disponible pour la science et dans le pire des cas, la défaillance d'un système de sécurité peut conduire à la destruction d'une partie de la machine. La nouvelle mise à niveau du LHC prévue pour 2025, le LHC à haute luminosité (HL-LHC) atteindra une luminosité annuelle cinq fois supérieure à celle de la version actuelle du LHC. Par conséquent, les niveaux de rayonnement générés par le fonctionnement de la machine vont également augmenter considérablement. Avec des niveaux de rayonnement aussi élevés, un nombre important de systèmes commerciaux seront exposés à des niveaux de rayonnement auxquels ils ne peuvent résister. Cela impliquera soit de concevoir des systèmes plus robustes et tolérants à base de COTS, soit de remplacer préventivement les systèmes avant leur fin de vie utile. Ainsi, alors qu'au cours des années précédentes, les effets singuliers (EEI) étaient la principale cause de défaillance, à l'avenir, l'effet cumulatif du rayonnement deviendra également une préoccupation majeure. Bien qu'un effort considérable ait été fait dans le passé sur le processus de qualification contre les défaillances induites par les SEE, le processus de qualification pour les effets cumulatifs du rayonnement est resté pratiquement inchangé. L'objectif de ces travaux était donc d'étudier comment la Radiation Hardness Assurance (RHA) du CERN pourrait être améliorée pour répondre à ce nouveau défi et s'assurer qu'aucune défaillance de système n'aura d'impact sur les opérations du LHC. Plusieurs activités ont été menées à cet effet : (i) l'étude des particularités de l'environnement radiatif du LHC et de son impact sur les composants et les systèmes qui y sont exposés, (ii) l'étude de l'adéquation des méthodes de qualification actuelles et le développement d'approches adaptées aux besoins du CERN et (iii) l'étude des méthodes fiables pour estimer la durée de vie des systèmesThe Large Hadron Collider (LHC), the largest and most powerful in the world, started in 2008 and is the last stage of CERN's accelerator complex. The LHC consists in a 27-kilometer ring of superconducting magnets allowing to accelerate two beams up to 7 TeV before colliding them at 14 TeV in one of the five experiments monitoring the result of the collision. The LHC allowed notably the discovery of the Higgs boson and other baryonic particles predicted by the standard model. The radiation environment of the LHC and its injection lines is composed of different particles over a large spectrum of energies, from GeV level down to meV level (e.g. thermal neutron). The electronic equipment operating in such a harsh radiation environment, mostly based on Commercial Off The Shelf (COTS) components, can experience failures induced by radiation effects. The criticality of the equipment can be very high, in the best case, the failure of a control system can lead to a beam dump, which can drastically the availability of the beam for science and in the worst case, the failure of a safety system can lead to the destruction of part of the machine. The new upgrade of the LHC planned for 2025, the High Luminosity LHC (HL-LHC) will achieve an annual luminosity five time higher than the current version of the LHC. Consequently, the levels of the radiation generated by the operation of the machine will also drastically increase. With such high radiation levels, a significant number of COTS-based systems will be exposed to radiation levels they cannot withstand. This will imply to either design more robust tolerant COTS-based systems and/or substitute preventively systems before their end of life. Thus, while in the previous years the Single Event Effects (SEEs) where the dominant cause of failure, in the future, cumulative radiation effect will as well become a major preoccupation. While a huge effort has been done in the past on the qualification process against SEE-induced failures, the qualification process for cumulative radiation effects, remained mostly unchanged. The aim of this work was, therefore, to investigate how the CERN’s Radiation Hardness Assurance (RHA) could be improved to respond to this new challenge and ensure that no system failures will impact the LHC operations. This involved several activities; (i) the study of the particularities of the LHC radiative environment and its impact on the components and systems exposed to it, (ii) the study of the suitability of current qualification methods and the development of approaches adapted to CERN’s needs and (iii) the study of reliable system lifetime estimation methods
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Sutton, Akil Khamisi. "Hardness assurance testing and radiation hardening by design techniques for silicon-germanium heterojunction bipolar transistors and digital logic circuits." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29778.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Cressler, John; Committee Member: Deo, Chaitanya; Committee Member: Doolittle, Alan; Committee Member: Keezer, David; Committee Member: May, Gary; Committee Member: Papapolymerou, John. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Цих, В. С. "Розроблення методу та засобу контролю дефектів ізоляції підземних трубопроводів." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2014. http://elar.nung.edu.ua/handle/123456789/4703.
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Дисертація присвячена питанню контролю ізоляційного покриття підземних трубопроводів на території технологічних об’єктів нафтогазового комплексу. Проведено аналіз основних методів і засобів контролю технічного стану ізоляційного покриття підземних трубопроводів. Поділено всі існуючі дефекти ізоляції на два види: наскрізні пошкодження та відшарування. Проаналізовано особливості дефекту ізоляційного покриття типу відшарування ізоляції та його вплив на зміну електричних характеристик підземного ізольованого трубопроводу. Доведено доцільність застосування електромагнітного фазового методу контролю для виявлення таких дефектів. Одержано аналітичну модель залежностей питомого зсуву фази для ділянки підземного трубопроводу з відшаруванням ізоляції. Спроектовано та змонтовано експериментальну модель ділянки підземного трубопроводу з різними дефектами ізоляційного покриття. Розроблено методику проведення експериментальних досліджень та експериментальний взірець інформаційно-вимірювальної системи. Проведено вимірювання основних інформативних параметрів на моделі підземного трубопроводу на навчально-науковому полігоні для технічної діагностики підземних комунікацій. Розроблено комплексний метод виявлення та ідентифікації дефектів ізоляційного покриття на основі аналізу двох інформативних параметрів (амплітуди та фази струму в стінках трубопроводу). Запропоновано методику виявлення дефектів ізоляційного покриття підземних трубопроводів, на основі якої розроблено проект нормативного документу (СОУ). Проведено апробацію методики та експериментального взірця інформаційно-вимірювальної системи для виявлення та ідентифікації дефектів ізоляційного покриття підземних трубопроводів.Диссертация посвящена вопросу контроля изоляционного покрытия подземных трубопроводов на территории технологических объектов нефтегазового комплекса, а именно - трубопроводов, размещенных на территории автомобильных газонаполнительных, компрессорных, газораспределительных и нефтеперекачивающих станций. Проведен анализ основных методов и средств контроля технического состояния изоляционных покрытий подземных трубопроводов, а также проанализированы главные проблемы, которые могут возникать во время контроля таких трубопроводов на территории технологических объектов нефтегазового комплекса. Разделены все существующие дефекты изоляционных покрытий на два вида - сквозные повреждения и отслоения изоляции. Особое внимание уделено дефектам типа отслоения, поскольку существующие подходы и методики контроля технического состояния изоляции не дают возможность определять местоположение таких дефектов с поверхности земли в виду особенности их характеристик. Проведены теоретические исследования по изменению удельного сдвига фазы измеряемого сигнала при изменении емкостей и соответственно геометрических параметров отслоений изоляционного покрытия. Доказана целесообразность применения электромагнитного фазового метода контроля для выявления таких дефектов. Получена аналитическая модель зависимостей сдвига фазы для участка подземного трубопровода с отслоением изоляции с учетом параметров грунта, в котором размещен исследуемый трубопровод. Разработана схема и создана экспериментальная модель участка подземного трубопровода с различными дефектами изоляционного покрытия (сквозными повреждениями и отслоениями изоляции) на специальном учебно-научном полигоне для технического диагностирования подземных коммуникаций. Предложена методика - проведения экспериментальных исследований, для чего создан экспериментальный образец информационно-измерительной системы. Проведены измерения основных информативных параметров (сдвига фазы и амплитуды тока в стенках) на модели подземного трубопровода на учебно-научном полигоне. На основании проведенных измерений значений тока в стенках исследуемого трубопровода получено экспериментальное подтверждение эффекта вытекания тока со свойственными изменениями в месте сквозного повреждения изоляции. Оценена возможность идентификации сквозного повреждения на основании оценки критических значений точек распределения хи-квадрат. Разработан комплексный метод обнаружения и идентификации дефектов изоляционного покрытия на основе анализа двух информативных параметров (удельного изменения значений тока в стенках трубопровода и удельного сдвига фазы измеряемого сигнала). Разработана методика определения местоположения повреждений изоляционных покрытий подземных трубопроводов на территории технологических объектов нефтегазового комплекса. Проведены полевые исследования, а также промышленная апробация методики и экспериментального образца информационно-измерительной системы для обнаружения и идентификации дефектов изоляционного покрытия подземных трубопроводов, которые подтвердили их работоспособность в условиях действующих объектов нефтегазового комплекса.
Thesis is devoted to the issue of insulated coating monitoring of buried pipeline situated at the oil and gas complex production facilities. The analysis of basic methods and equipment for technical condition of buried pipelines insulated coating monitoring is realized. All existing coating defects are divided into two types: holes and coating disbondings. Coating disbonding damage singularity and its influence on buried insolated pipeline electrical parameters variances is analyzed. The feasibility of the phase electromagnetic testing method for such damages detection is proved. An analytical model of specific phase displacement for buried pipeline section with coating disbonding is deduced. An experimental model of buried pipeline section with different coating damages is planed and constructed. The technique of experimental investigations and operative embodiment of information and measuring system are developed. The measuring of the fundamental information-bearing parameters at the model of buried pipeline situated at the special educational and scientific training range for buried utilities technical diagnostic is made. A complex method for coating damages detection and identification on the basis of two information-bearing parameters analyzes (the range and the phase of pipeline current) is developed. The technique of buried pipelines coating damages detection is suggested whereby a standardized document project has been developed. An approvement of technique and information and measuring system for buried pipeline insulated coating damages detection and identification is made.
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Min-HsiangHu and 胡閔翔. "Damage Assessment of Nonlinear Structures Based on theNormalized Relative Displacement Vibration Shape." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/10575742260036696853.
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碩士國立成功大學
土木工程學系碩博士班
100
This study presents a damage assessment scheme for seismically-excited torsion-coupled nonlinear buildings based on the normalized relative displacement vibration shape (NRDVS). In order to investigate the applicability of proposed NRDVS, the relative displacements are obtained from a real-time structural response integrator (RTSRI) by integrating the relative accelerations simulated from multiple-degree-of -freedom nonlinear models and torsion-coupled models. As a result, the normalized inter-story drift ratio (NIDR) calculated by differencing the normalized displacements of the two successive floors of NRDVS and dividing by the story height can reveal the damaged floors as well as the location of damaged building members. Furthermore, the proposed damage assessment scheme is validated by observing the experimental measurements of shaking table tests of two steel frame models (Benchmark D and Benchmark G) and three scaled-down two-story reinforced concrete school building models conducted at National Center for Research on Earthquake Engineering (NCREE), Taipei, Taiwan.
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Wu, Yi-Ying, and 吳怡瑩. "A damage indicator for building-soil systems using dynamic displacement frequency response functions." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/33073809822771770129.
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碩士國立臺灣科技大學
營建工程系
104
This study develops a damage detection method for building-soil systems. A normalized damage indicator (NDI) utilizing frequency response functions is proposed to localize damaged stories in building structures. To evaluate the proposed damage indicator, a numerical example of a five-story RC building subjected to harmonic waves is investigated in this study. The influence of the random noise and the structural damage extent as well as soil shear velocity are examined. In addition, the new approach is further applied in the earthquake analysis. The ROC curve analysis is also implemented to qualify the detection performance of the damage indicators and two existing FRF-based damage indicators are employed for a comprehensive comparison. The analyzed results show that the two existing damage indicators are significantly affected by the random noise with a rather low accuracy in detecting damage of heavy buildings situated on soft soil. In contrast, even though a high level of noise is considered, NDI is able to detect slightly damaged stories in the buildings with relatively high accuracy. The accuracy of this indicator may also be improved by shortening the frequency intervals. Furthermore, NDI has the best detection performance among all three indicators in fixed-base models; for building-soil systems, NDI shows its ability to incorporate the effects of soil-structure interaction efficiently.
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Ruei-LinWu and 吳瑞琳. "A Rapid Structural Damage Assessment Scheme Based on the Normalized Relative Displacement Vibration Shape." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/35828273812642250050.
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Wen-JenHuang and 黃文仁. "Study on the Correlation of Normalized Relative Displacement Vibration Shape to Building Damage Level." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9pdt3r.
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碩士國立成功大學
土木工程學系碩士在職專班
107
The purpose of this paper is to try to use the existing seismic monitoring data of the building, apply the system identification method to obtain the Normalized Relative Displacement Vibration Shape (NRDVS) of the structure, and calculate the Normalized Inter-story Driift Ratior (NIDR) calculated by NRDVS. The change situation, as the basis for determining the seismic damage classification of buildings, provides another selection method for quicker and more accurate judgment by providing structural damage classification. this paper is to use the Normalized Relative Displacement Vibration Shape (NRDVS) theory of the building mentioned in the literature, the shaking table test of the one-third scale two-story RC school building model in the same literature is analyzed, and the normalization of each stage of the model test body is carried out. The overall or local incremental data of the Normalized Inter-story Driift Ratior(NIDR) is established as a seismic damage classification reference table of the Normalized Inter-story Driift Ratior (NIDR). Finally, this paper uses the long-term seismic monitoring signal data of the real building structure of the old building of Taitung Fire Bureau to establish a Normalized Relative Displacement Vibration Shape (NRDVS), and calculates the Normalized Inter-story Driift Ratior (NIDR) overall or local incremental data to verify the Normalized Inter-story Driift Ratior (NIDR) seismic damage classification reference table application feasibility, verification results This paper determines that the seismic damage level of the building structure is consistent with the emergency assessment results of the original exploration after the earthquake.
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Li, Chi-Hang, and 李其航. "Application of Spatial Displacement Measurement on Damage Assessment from both Local and Global Structural System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/08694090033252055998.
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碩士國立臺灣大學
土木工程學研究所
100
In this research, the capability of advance spatial displacement measurement for structural health monitoring (SHM) is studied. The method for obtaining this kind of data is different from regular measuring system. It utilizes the optical processing technique to calculate the specific particles’ locations (called targets) within an image. While taking image and compute the locations over time, the dynamic motion can be estimated. This research employed the three dimensional displacement from optical sensors to identify system and perform damage assessment. The applied signal analysis methodologies can separate into two categories, global system identification and local element motion detection. For global system, two subspace methods including 1.covariance-driven stochastic subspace identification (SSI-COV) and 2.recursive subspace identification (RSI) are examined. They can obtain the system natural frequency and damping ratio based on different condition. The other method is 3.principal component analysis (PCA), which the system normal modes can be briefly calculated while the measured locations are distributed along the system. For local motion, we can discretize the targets into a set of local elements. These elements motion is detect by 4.singular spectral analysis (SSA), 5.continuous wavelet transform (CWT), and 6.finite element method (FEM). The extracted information is used to describe the structural local properties and detect the damage occurrence. To examine the applications of these methodologies on real three dimensional displacement data, a shake table test of one-story two-bay RC frame performed in the NCREE is selected. This experiment installed a totally integrated optical measuring system (DMM, by NDI Inc.) on its central column to obtain the displacement. The analysis results show that this kind of data is capable for system identification, and the detection of damage is also feasible. Detail analyzes the discrete elements. The damage location may be obtained.
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Diederichs, Anna K. "Geodetic methods of mapping earthquake-induced ground deformation and building damage." Thesis, 2020. http://hdl.handle.net/1828/12031.
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I use temporal lidar and radar to reveal fault rupture kinematics and to test a method of mapping earthquake-induced structural damage. Using pre- and post-event data, these applications of remote technology offer unique perspectives of earthquake effects. Lidar point clouds can produce high resolution, three-dimensional terrain maps, so subtle landscape shifts can be discerned through temporal analysis, providing detailed imagery of co-seismic ground displacement and faulting. All-weather radar systems record back-scattered signal amplitude and phase. Pre- and post-event comparisons of phase can illuminate co-seismic structural damage using an oblique look angle, most sensitive to changes in building heights. Extracted information from these geodetic methods may be used to inform decisions on future earthquake modeling and emergency response. In the first major section of this thesis, I calculate co-seismic 3D ground deformation produced by the Papatea fault using differential lidar. I demonstrate that this fault - a key element within the 2016 Mw 7.8 Kaikoura earthquake - has a distinctly non-planar geometry, far exceeded typical co-seismic slip-to-length ratios, and defied Andersonian mechanics by slipping vertically at steep angles. Its surface deformation is poorly reproduced by elastic dislocation models, suggesting the Papatea fault did not release stored strain energy as typically assumed, perhaps explaining its seismic quiescence in back-projections. Instead, it slipped in response to neighboring fault movements, creating a localized space problem, accounting for its anelastic deformation field. Thus, modeling complex, multiple-fault earthquakes as slip on planar faults embedded in an elastic medium may not always be appropriate. For the second major part of this thesis, I compare mean values of interferometric synthetic aperture radar (InSAR) coherence change across four case studies of earthquake-induced building damage. These include the 2016 Amatrice earthquake, the 2017 Puebla-Morelos earthquake, the 2017 Sarpol-e-Zahab earthquake, and the 2018 Anchorage earthquake. I examine the influences of environmental and urban characteristics on co-seismic coherence change using Sentinel-1 imagery and compare the outcomes of various damage levels. I do not find consistent values of mean coherence change to distinguish levels of damage across the case studies, indicating coherence change values vary with location, environment, and damage pattern. However, this method of damage mapping shows potential as a useful tool in earthquake emergency response, capable of quickly identifying localized areas of high damage in areas with low snow and vegetation cover. Given the large spatial coverage and relatively quick, low-cost acquisition of SAR imagery, this method could provide damage estimates for unsafe or remote regions or for areas unable to self-report damage.Graduate
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Ayyildiz, Muhammed. "Scales Depencence of Fracture Density and Fabric in the Damage Zone of a Large Displacement Continental Transform Fault." Thesis, 2012. http://hdl.handle.net/1969.1/148095.
Full textAbstract:
Characterization of fractures in an arkosic sandstone from the western damage zone of the San Andreas Fault (SAF) at San Andreas Fault Observatory at Depth (SAFOD) was used to better understand the origin of damage and to determine the scale dependence of fracture fabric and fracture density. Samples for this study were acquired from core taken at approximately 2.6 km depth during Phase 1 drilling at SAFOD. Petrographic sections of samples were studied using an optical petrographic microscope equipped with a universal stage and digital imaging system, and a scanning electron microscope with cathodoluminescence (SEM-CL) imaging capability. Use of combined optical imaging and SEM-CL imaging was found to more successfully acquire true fracture density at the grain scale. Linear fracture density and fracture orientation were determined for transgranular fractures at the whole thin section scale, and intragranular fractures at the grain scale. The microscopic scale measurements were compared to measurements of mesoscopic scale fractures in the same core, as well as to published data from an ancient, exhumed trace of the SAF in southern California. Fracturing in the damage zone of the SAF fault follows simple scaling laws from the grain scale to the km scale. Fracture density distributions in the core from SAFOD are similar to distributions in damaged arkosic sandstone of the SAF along other traces. Transgranular fractures, which are dominantly shear fractures, indicate preferred orientation approximately parallel to the dominant sets of the mesoscale faults. Although additional work is necessary to confirm general applicability, the results of this work demonstrate that fracture density and orientation distribution over a broad range of scales can be determined from measurements at the mesoscopic scale using empirical scaling relations.
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林一鳴. "The damage ratio assessment of water pipelines based on 921 seismic displacements measured at triangular points." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/28354574559686310541.
Full textAbstract:
碩士國立臺北科技大學
環境規劃與管理研究所
91
The common way to study the scenario of lifeline damages caused by earthquake is to establish the relationship of repair rate and earthquake parameters. This study focuses on the parameter of Permanent Ground Deformation (PGD) to construct water pipeline damage model. During the analysis for each town, the range of repair rate and PGD data are limited, which causes pronounced impacts with respect to regression due to a little variation. In addition, the grid-based analysis also introduces the uncertainty from the discreteness of spatial elements. Lengths of water pipeline between each grid could be estimated as relatively low when it is located just around the border of study area, which leads to high repair rate in each grid. With the analysis through GIS in the high repair rate area, PGD changed obviously compared to the grid in neighbor. Therefore, PGD-difference model is constructed to further discuss on the relationship of PGD-difference and repair rate. PGD-difference model of single town indicates that it’s more conforming to realistic situation. In this study, we also applied Strain gage Rosettes method to construct a damage model to evaluate ground strain, which is even more conforming to realistic situation comparing to other two methods. Besides the derivations of regression models for lifeline damage estimation, the models were also examined with Toprak’s and Heubach’s models.
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Wildy, Stuart James. "Scanning laser doppler vibrometry for strain measurement and damage detection." Thesis, 2012. http://hdl.handle.net/2440/93519.
Full textAbstract:
Numerous strain measurement and damage detection techniques have been developed over the last century. These techniques include strain gauges, digital image correlation, radiography and ultrasonic inspections. All have various advantages, as well as disadvantages, which make each suited to specific applications. With the development of laser Doppler vibrometry, a number of techniques have been established for non-destructive evaluation, such as the measurement of bending strain, as well as damage detection using kinematic parameters, including displacement and curvature. With recent advancements in laser Doppler vibrometry technology (such as 3D scanning laser Doppler vibrometry for three-dimensional displacement measurements, improved velocity decoders and increased spatial resolution) the door has been opened to develop techniques for measuring surface strain from in-plane displacements, as well as the development of new damage detection techniques based on the fundamental principle of deformation:- the governing differential equation of displacement. The extensive literature review contained in this thesis identified a number of gaps in the field, including the evaluation of the accuracy of quasi-static bending strain measurements using current 1D SLDV technology, the precision of full-field surface strain measurement techniques utilising 3D SLDV, and new detection techniques based on the violation of the governing differential equations of displacement. Thus, the research contained in this thesis focussed on these areas. The first part of this thesis presents an investigation into the use of 1D and 3D scanning laser Doppler vibrometry for non-contact measurement of quasi-static bending strain in beams and surface strain in plates, respectively. The second part presents a new damage detection technique based on the governing differential equations of displacement in beam and plate structures. Two algorithms are developed to determine a violation in the governing differential equations created by either a delamination in a composite beam with out-of-plane displacements, or by a crack in a plate with in-plane displacements.Thesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2012
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Lee, Tai-Kuang, and 李泰廣. "Application of Endochronic Viscoplasticity with Cyclic Damage to Sn/3.5Ag/0.75Cu Solder Joint Specimens under Cyclic Proportional Displacement Path." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/62006065891178527327.
Full textAbstract:
碩士國立成功大學
工程科學系碩博士班
95
In order to find stress-strain-damage behavior of solder ball by using solder joint specimen, this thesis defined, at first, the stiffness of material testing system, whose value could be determined from the slope of linear range of loading or unloading of the load-displacement hysteresis loop. Within this range, the solder joints behaved linear elastic with Young’s modulus and shear modulus of bulk material. As a result, the (elastic) stiffness of solder joint specimen under proportional displacement path (Φ) could be determined. Employing the series combination of spring for material testing system, the stiffness of grips could be calculated, whose value was fixed under its corresponding proportional displacement path. Consequently, the load-displacement hysteresis loop of solder joint specimen could be constructed. In this paper, isothermal undamage simple shear test data of solder joint specimen having 9 Sn/3.5Ag/0.75Cu balls were used as a base to determine the kernel function of endochronic viscoplasticity and the material function in the intrinsic time measure whose values were increased from Φ=90° to 0° but decreased as increased of the effective inelastic strain amplitude. Based on these, the isotropic endochronic viscoplasticity with cyclic damage under various proportional displacement path was used to compute load-displacement hysteresis loops. The computational results were in excellent agreement with data. According to Lee’s evolution equation of cyclic damage and the small increase in effective inelastic strain amplitude with increasing cyclic number, the relationship between damage factor D and the cyclic number N could be derived: , here was increased both from Φ=90° to 0° and the increase of effective inelastic strain amplitude. But the trend of was reversed. Usage of data of D vs. N curves and load-displacement hysteresis loops of various Φ, critical values of damage factor could be determined, 0.4
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Chang, Jun-Wei, and 張峻偉. "Prediction Fatigue Initiation Life of 63Sn/37Pb Solder Joint Specimens under Cyclic Proportional Displacement Path Via The Endochronic Viscoplasticity with Cyclic Damage." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/69684114299140282725.
Full textAbstract:
碩士國立成功大學
工程科學系碩博士班
96
In 2007, for the solder joint Sn/3.5Ag/0.75Cu cyclic proportional displacement path, Lee and Lee proposed the modification of solder joint specimen with stiffness of material testing system, and figured out the grip stiffiness by using series connetion concept. In 2002, Park used the same way to make the experiment with 63Sn/37Pb solder joint. In this paper, the material parameters , and were determined with Lee and Chen research on a 63Sn/37Pb bar whose area is , and the length is . Combining the material parameters and specimen parameter which were getting from Lee and Lee to run the endochronic viscoplaticity increment form consideration, passed through above step to proof that whether the material parameters with same material but different geometry and size become changed or not. From the evolution equation of cyclic damage which proposed by Lee and Chen, getting a relationship between damage factor and cyclic fatigue life. In this paper, for a fixed damage parameter D=0.5, the figure displacement correspond to fatigue life, citing the damage parameter which was proposed by Lee and Chen to become the damage parameter daturn whose angle equal to 0, and citing the Sn/3.5Ag/0.75Cu solder joint specimen parameter proposed by Lee and Lee to obtain the damage parameters whose angle is equal to 45 or 90. From above information, citing the Coffin-Manson modification and combining with the critical damage parameter to estimate the fatigue initiation life, after that, establishing the relationship between system displacement range and effect inelastic strain range and combining the Coffin-Manson modification to obtain the initiation fatigue life immediately.
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Lin, Tai-tin, and 林泰廷. "Prediction of Fatigue Initiation Life of BGA (Sn/3.5Ag/0.75Cu) Solder Joint Specimens under Cyclic Proportional Displacement Path via Damage Coupled Endochronic Viscoplasticity." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/05206097374183755900.
Full textAbstract:
碩士國立成功大學
工程科學系碩博士班
97
The purpose of this paper is to investigate the fatigue initiation life prediction of BGA (Sn/3.5Ag/0.75Cu) solder joint specimens under mixed mode cyclic proportional displacement path( ) .First, by using the BGA solder joint standoff 0.52mm to adjust the displacement-loading data of the master's thesis of Lee, T. K. in 2007. And continue with using the material parameters and kernel function of Endochronic cyclic viscoplasticity to simulate cyclic stress-strain curve under proportional displacement path. Then using the effective inelastic strain and effective stress , the relation was established. This paper(1) aim to employ damage effective strain in parameter that depend on elastic strain energy density release rate and damage rate. (2)Using the definition of intrinsic damage time to establish evolution equation of intrinsic damage under cyclic proportional displacement path. This paper purpose the power form relation between damage accumulate rate and numbers of cycle N. Then damage factor can be derived from the relation, by cyclic loading amplitude vs. N data could compute and n. The results find that depend on , and , n is independence from . Endochronic fatigue life prediction under proportional displacement path , is independence from , but , therefore the result of figure vs. depend on , the result under the different scope of , Coffin-Manson relationship can be expressed by straight lines.