Dissertations / Theses: 'Fault properties'

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Kelly, Christina. "Understanding seismic properties of fault zones." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/17861/.

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Fault zone properties at depth are often inferred from seismic properties such as seismic velocities and attenuation. An understanding of how fault zone properties and processes influence seismic measurements is required for successful interpretations to be made. As fault zones are heavily fractured and often fluid-rich areas, a knowledge of the influences of cracking and fluid content on seismic measurements is needed. This will allow better interpretation of fault zone properties and how they may change at the time of an earthquake. Research presented in this thesis is concentrated on two regions of strike-slip faulting: the Parkfield area of the San Andreas fault and the exhumed Carboneras fault zone region of SE Spain. Well-preserved exhumed faults allow observation of fault structure at seismogenic depths. The structure of the exhumed Carboneras fault has previously been suggested as an analogue for the Parkfield area at depth. Laboratory measurements can help us to determine what processes occur at seismogenic depths in active faults. They can also aid in interpretation of seismic studies. In this thesis laboratory and seismic studies are brought together in order to gain a greater understanding of fault zone seismic properties at depth and how to interpret them. In order to characterise the properties of the Carboneras fault, laboratory experiments of velocities through fault gouge and fault zone rocks are performed. The influences of fracture damage and local geological fabric on velocities are investigated. Gouge velocities are measured to be less than those of the mica schist rock through which the fault cuts. Velocity changes due to variations in crack damage in cyclic loading experiments are less than 5% of the original rock velocity. Strong velocity anisotropy is observed in the mica schist, with velocities of the order of 30% less when measured perpendicular to the strong foliation present in the rock. The consequences in terms of seismically imaging the fault zone are discussed. The effects of this strong velocity anisotropy need to be considered for specific source-receiver geometries and the local geological fabric in the locations of seismic experiments. Surface wave tomography and ambient noise analysis of the Carboneras fault zone region shows that faults are imaged as low velocity features at depth. Results suggest that velocities are reduced by approximately 10% at depths close to 3 km. The strong anisotropy observed in laboratory experiments of mica schist may also have implications for seismic imaging of this region as this rock crops out widely. This is discussed in terms of a potentially strong crustal component to shear-wave splitting observations in the region. In the second part of the thesis, temporal changes in seismic attenuation at the time of the 2004 M6.0 Parkfield earthquake are investigated. Seismic attenuation can give indications of fracture damage and healing. Spectral ratios between earthquakes within repeating clusters are calculated. A sharp increase in attenuation is observed immediately after the earthquake, which then decays over the next 2 years. The postseismic decay is fit by a logarithmic function. The timescale of the decay is found to be similar to that in GPS data and ambient seismic noise velocities following the 2004 M6.0 Parkfield earthquake. The amplitude of the attenuation change corresponds to a decrease of approximately 10% in QP at the time of the earthquake. The greatest changes are recorded to the northeast of the fault trace, consistent with preferential damage in the extensional quadrant behind a north-westerly propagating rupture tip. Our analysis suggests that significant changes in seismic attenuation and hence fracture dilatancy during co-seismic rupture are limited to depths of less than about 5 km.

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Mitchell, Thomas Matthew. "The fluid flow properties of fault damage zones." Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485852.

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Quantification of the fluid flow properties of the Earth's crust is an essential precursor to the understanding of a wide range of geological processes, including earthquake generation and crustal strength, and the recovery of natural resources. Faults playa key role in the migration of fluids around the ;Earth's crust, and therefore the fluid flow properties of fractured rocks and how these properties evolve with time are of major importance. This thesis aims to improve our understanding of the hydraulic transport properties of large fault zones by presenting a large dataset of detailed field and microstructural observations and results from a suite of laboratory experiments to provide a basis for studying the distribution, and fluid flow properties, of damage surrounding large natural fault zones. Damage surrounding the core of faults is represented by both microfracturing of the rock matrix and by macroscopic fracture networks. Microfracture and macrofracture densities and orientations have been analysed on strike slip faults with displacements ranging over 3 orders of magnitude (~O.l2 m - 5000 m). These faults cut crystalline rock within the excellently exposed Atacama Fault Zone, Northern Chile. All faults consist of a fault core and associated damage zone. Damage zone width as defined by macrofractures and microfractures scale with displacement and fault length. Both microfractures (specifically fluid inclusion planes) and macrofractures within the damage zone show a log-linear .decrease in fracture density with perpendicular distance from the fault core. An empirical equation for microfracture density distribution based on the evolution of displacement has been derived for these faults. Preferred microfracture orientations in the damage zone suggest that this damage may predominantly be due to early processes related to enhanced stress at fault tips, in addition to cumulative wear processes from the juxtaposition of geometrical irregularities on the fault plane and damage from dynamic rupture. Fault core widths scale with displacement, with the largest displacement fault showing a wide multiple core zone. Detailed experimental studies of the development of permeability of crustal rock during deformation are essential in helping to understand fault mechanics and constrain larger scale models that predict bulk fluid flow within the crust. The strength, permeability and pore fluid volume evolution of initially intact crystalline rock under increasing differential load leading to macroscopic failure has been determined at water pore pressures of 50 MPa and varying effective pressures from 10 to 50 MPa. Permeability is seen to increase by, up to, and over two orders of magnitude prior to macroscopic failure, with the greatest increase seen at lowest effective pressures. Post-failure permeability is shown to be over three orders of magnitude higher than initial intact permeabilities and approaches the lower the limit of measurements of in situ bulk crustal permeabilities. Increasing amplitude cyclic loading tests show permeabilitystress hysteresis with high permeabilities maintained as differential stress is reduced and the greatest permeability increases are seen between 90-99% of the failure stress. Under hydrothermal conditions without further loading, it is suggested that much of this permeability can be recovered by healing and sealing, and pre-macroscopic failure fracture damage may heal relatively faster than post-failure macroscopic fractures. Pre-failure permeabilities are nearly seven to nine orders of magnitude lower than that predicted by some high pressure diffusive models suggesting that microfracture matrix flow cannot dominate, and agrees with inferences that bulk fluid flow and dilatancy must be dominated by larger scale structures, such as macrofractures. It is suggested that the permeability of a highly stressed fault tip process zone in low-permeability crystalline rocks could increase by more than 2 orders of magnitude, while stress drops related to fracture propagation close damage zone cracks, and some permeability is maintained due to hysteresis from permanent microfracture damage. Future work should aim to quantify experimentally-induced microfractures and. associated permeability measurements, and by relating the fracture densities surrounding natural fault zones with densities seen in experimental deformed samples with known permeabilities, modelling techniques can then be applied to gain estimates of bulk fluid flow of the fracture networks. This will provide a basis for predicting the influence of pore fluid pressures on important geological issues, such as crustal strength.

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Childs, Conrad James. "The structure and hydraulic properties of fault zones." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367208.

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Heermance, Richard V. "Geometry and Physical Properties of the Chelungpu Fault, Taiwan, and Their Effect on Fault Rupture." DigitalCommons@USU, 2002. https://digitalcommons.usu.edu/etd/6720.

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Rupture of the Chelungpu fault during the September 21, 1999, 7.6 Mwearthquake in Taiwan caused a 90-Jr,m-long surface rupture with variable displacement along strike. Analysis of core from two holes drilled through the fault zone, combined with geologic mapping and detailed investigation from three outcrops, define the fault geometry and physical properties of the Chelungpu fault in its northern and southern regions. In the northern region, the fault dips 45-60° east parallel to bedding and consists of a narrow (1-20 cm) core of dark-gray, sheared clay gouge at the base of a 30-50 m zone of increased fracture density that is confined asymmetrically to the hanging wall. Microstructural analysis of the fault gouge indicates the presence of extremely narrow clay zones (50-300 μm thick) that are interpreted as the fault rupture surfaces. Few shear indicators are observed outside of the fault gouge, which implies that slip was localized in the gouge in the northern region. Slip localization along a bed-parallel surface resulted in less high-frequency ground motion and larger displacements during the earthquake than in the southern region. Observations from the southern region indicate that the fault dips 20-30° at the surface and consists of a wide (20- 70 m-thick) zone of sheared, foliated shale with numerous gouge zones. A footwall-ramp geometry juxtaposes 2000-3000 m of flat-lying Quaternary Toukoshan Formation in the footwall with Pliocene and Miocene, east-dipping siltstone and muds tone in the hanging wall. The wide, diffuse fault zone contributed to the lower displacement and higher frequency ground motion in the southern region during the 1999 earthquake. The structure in the northern region is the result of the fault being a very young (<50 >ka) fault segment in the hanging wall of an older segment of the Chelungpu fault, buried in the Taichung basin. The fault in the southern region is located on an older (~1 Ma) fault trace. The contrasting fault properties in the different regions are responsible for the variability in strong-motion and displacement observed during the 1999 earthquake.

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Pandey, Amit Nath. "Fault detection of multivariable system using its directional properties." Texas A&M University, 2004. http://hdl.handle.net/1969.1/3354.

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A novel algorithm for making the combination of outputs in the output zero direction of the plant always equal to zero was formulated. Using this algorithm and the result of MacFarlane and Karcanias, a fault detection scheme was proposed which utilizes the directional property of the multivariable linear system. The fault detection scheme is applicable to linear multivariable systems. Results were obtained for both continuous and discrete linear multivariable systems. A quadruple tank system was used to illustrate the results. The results were further verified by the steady state analysis of the plant.

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Al-Busafi, Bader. "Incorporation of fault rock properties into production simulation models." Thesis, University of Leeds, 2005. http://etheses.whiterose.ac.uk/190/.

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This thesis has two aims. First, to investigate the importance of incorporating the multiphase flow properties of faults into production simulation models. Second, to investigate methodologies to incorporate the multiphase flow properties of faults into production simulation models. Tests using simple simulation models suggest that in some situations it is not particularly important to take into account the multiphase flow properties of faults, whereas in other situations the multiphase properties have proved very important. The differences depend on drive mechanism, well position, and the capillary pressure distribution along the fault as well on the parameters that need to be modelled (e. g. bottom-hole pressures, hydrocarbon production rates, water cuts, etc. ). The results show that it is possible for hydrocarbons to flow across a sealing fault (i. e. 100% water saturation) as a result of its threshold pressure being overcome. The relative permeability of fault rocks may be one of the largest unknowns in simulating fluid in structurally complex petroleum reservoirs. Microstructural and petrophysical measurements are conducted on faults from core within the Pierce Field, North Sea. The results are used to calculate transmissibility multipliers (TMs) required to take into account the effect of faults on fluid flow within the Pierce production simulation model. The fault multiphase flow behaviour is approximated by varying the TMs as a function of height above the free water level. This methodology results in an improved history match of production data. Further, the improved model is then used to plan the optimal time to conduct a follow-up 3D seismic survey to identify unswept compartments. Further, an alternative model was proposed to overcome some of the possible limitations that the previous TM treatments may have at certain stages of a reservoir life. The similar behaviour of the different proposed fault models for the Pierce Field indicate that the current faulting system in this model is not largely responsible for the history mismatch in water production. Multiphase flow properties of faults can be incorporated into production simulation models using dynamic pseudofunctions. In this thesis, different dynamic pseudofunctions are generated by conducting high-resolution fluid flow models at the scale of the reservoir simulation grid block, using flow rates similar to those that are likely to be encountered within petroleum reservoirs. In these high-resolution models, both the fault and reservoir rock are given their own capillary pressure and relative permeability curves. The results of the simulations are used to create pseudocurves that are then incorporated into the up-scaled production simulation model to account for the presence of both the fault and undeformed reservoir. Different flow regimes are used to compare the performance of each pseudoisation method with the conventional, single-phase TM fault representations. The results presented in this thesis show that it is more important to incorporate fault multiphase properties in capillary dominated flow regimes than in those that are viscosity dominated. It should, however, be emphasised that the Brooks-Corey relations used to estimate relative permeability and capillary pressure curves of the fault rock in this study have a significant influence on some of these conclusions. In other words, these conclusions may not be valid if the relative permeability curves of fault rocks are very different to those calculated using the aforementioned relationships. Finally, an integrated workflow is outlined showing how dynamic pseudofunctions can be generated in fault juxtaposition models by taking advantage of the dynamic flux preservation feature in Eclipse 10OTM simulator.

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Shar, Abdul Majeed. "Petrophysical properties of fault rock : implications for petroleum production." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10434/.

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Faults can have significant impact on reservoir productivity. Understanding the factors that controls the fluid flow properties of fault rocks provides a sound basis to assess the impact of faults on reservoirs productivity. Therefore, different aspects that affect the fluid flow within siliciclastic fault formations were investigated in this research project. Fault rock samples from a number of locations were analysed including: (i) core samples from central and southern North Sea fields; (ii) and outcrop samples from the 90 Fathom fault, Northumberland, UK and Miri airport road exposure, Malaysia as well as the Hopeman fault from Invernesshire, UK. The impact of faults on fluid flow was assessed by integrating the data from QXRD analysis, microstructural examination, X-ray tomography, mercury porosimetry for pore size distribution, absolute and relative permeability measurements as well as capillary pressure tests. Single phase and multiphase flow properties which were conducted at a range of stresses are the most comprehensive collection of high quality fault rock data. The permeability measurements made using gas gave higher values than with brine, which in turn gave higher values that when measured using distilled water permeability. The differences in permeability could be the results of clay particles swelling; mobilisation and retaining within the confined pore throats, although these effects depend on the rock mineralogy and pore fluid composition. Moreover, the permeability stress sensitivity was investigated. The results showed that at low confining stresses the permeability of the fault rock core samples showed high sensitivity to stress, whereas at higher confining stresses the permeability was less pronounced to stress. This might be due to the core damage effects and the microfractures formed due to stress release, which were observed from SEM images. The pore radius calculated from gas slippage parameters at low confining pressures was in the same order of magnitude as the micro fracture width. The micro cracks could be easily closed due to stress increase hence resulted in reduction of permeability. Overall, the stress sensitivity of fault rocks from outcrop is less than that from core. This is consistent with the idea that stress sensitivity is mainly the result of the presence of grain boundary microfractures formed as core is brought to the surface. This indicates that permeability measurements made on outcrop samples may be more reliable. Another key finding was that the published permeability data (e.g. Fisher and Knipe, 2001) compared with present study data which is obtained at in-situ stress using formation compatible brines showed that the published data may not be inaccurate as the use of distilled water gives lower permeability than brines and low stresses resulted in higher permeability than in-situ stress measurements. Therefore, the results indicate that two different laboratory practices used in previous studies partially cancel each other out so that the existing data is yet valuable. The effective gas permeability were also measured at a range of stresses and it was observed that the samples with lower absolute permeabilities were more stress sensitive to stress than high permeable samples. The relative permeability results obtained were incorporated into a specific example of synthetic reservoir model. These suggested that faults formed within low permeability sands might act as a barrier to fluid flow.

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Park, Intaik. "Fault properties and their uses in testing digital integrated circuits /." May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.

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Curtis, Daniel J. "Analysis of the Hite Fault Group, Southeast Utah: Insights into Fluid Flow Properties in a Reservoir Analog." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6538.

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In the subsurface faults can act as both barriers and conduits for fluids or gases such as CO2, hydrocarbons, or water. It is often thought that faults in porous rocks such as sandstone are barriers to fluid flow. In this study we show that this is not always the case. In sandstones like the Cedar Mesa Sandstone it is very important to understand the relationships between this history of fault slip and fluid flow. Better understanding of how fluids migrate through faults and the damaged areas surrounding these faults has strong significance to the oil and gas industry. In this study we examine a group of faults and their surrounding damage zones near Hite, Utah. We analyze three of these small-scale faults in more detail. In doing so we give insights into how these faults and their damage zones can effect fluid migration as well as the porosity and permeability in the Cedar Mesa Sandstone. Whole rock geochemistry, X-ray diffraction mineralogy, permeability data, petrography, ultraviolet photography, and outcrop observations were used to gain insights into cross-cutting relationships, past fluid compositions, and fault characteristics. From the data that was collected from these faults we have begun to describe a series of structural and fluid flow events. This series allows us to say that small-scale faults and fractures are features by which fluids can migrate preferentially. In this series of events we isolate two separate phases of movement. The first phase of movement being has a component of shear in which the edges of the fractures are not moving directly apart. This event is accompanied by a fluid flow event the emplaced iron oxide in the fractures and the surrounding formation. The second event is a phase when the faults become reactivated by a stress that created open mode fractures. This second is accompanied by a fluid flow event that has high calcium content and emplaces calcite in the fractures. Throughout this study we give evidence to support this series of movement and fluid events.

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Haines, Thomas J. "The evolution of petrophysical properties across carbonate hosted normal fault zones." Thesis, University of Aberdeen, 2014. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225315.

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Haneef, Javed. "Single and multiphase flow properties of fault rocks : implications for petroleum production." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/13441/.

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Geological faults are known to have a major impact on fluid flow in the subsurface and may developed isolated compartments for hydrocarbon reservoirs. The knowledge of their properties is important for petroleum industries within interests that include oil and gas production, Carbon dioxide storage and radioactive waste disposal. Large data sets have been collected on the single-phase permeability of fault rocks but these have been collected under inappropriate laboratory conditions such as low confining pressures and using distilled water as the permeant. Some data have been published on the gas relative permeability of fault rocks but no data is available on oil-water relative permeabilities or from fault rocks that are not strongly water-wet. The current thesis aims to produce high quality experimental data to partly fill these knowledge gaps by collecting gas and brine absolute permeability data from fault rocks at reservoir stress conditions using a formation compatible brine as well as oil-water relative permeabilities from fault rocks that are water-wet and after wettability alteration so that they become less water wet. The key findings of this thesis show that the absolute permeability of fault rocks is very stress sensitive due to the presence of microfractures created during coring or core-retrieval. The stress sensitivity of permeability increases with decreasing permeability. On average, fault rocks have a permeability at in situ stress which is ~ 20% that measured at ambient conditions. Permeability is also found to be less sensitive to brine composition, with permeabilities to distilled water being around 20% those when measured with brine. So the effects of two poor laboratory practices cancel each other out meaning that much published data remain usable. The obtained results from oil water relative permeability measurements of water-wet cataclastic faults are consistent with what is known about grain-sorting controlling relative permeability. The changes in wettability resulting from aging the samples in crude oil are also consistent with what would be expected when the wettability of samples is altered to being neutral to oil-wet. These results raise the possibility that fault rocks in some reservoirs may not be strongly water-wet and will therefore not act as capillary barriers. A new clay-mixing model is also presented, which explains the scatter on permeability vs clay content that is used as input for calculating fault transmissibility multipliers in production simulation models. The obtained results can be used as the analogues for similar fault rock types and implemented in the reservoir simulation models for the future forecast of hydrocarbon production.

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Strauss, Becky. "Magnetic Properties of the Bishop Ash in the San Andreas Fault Borderlands." Oberlin College Honors Theses / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1411725129.

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Michie, Emma A. H. "The influence of damage on the petrophysical properties of carbonate-hosted fault zones." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=227220.

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Carbonate reservoirs contain approximately two-thirds of the world's oil and gas reserves (Al-Anzi et al., 2003). Carbonates often pose a significant problem when it comes to understanding their reservoir quality because of their heterogeneous nature, which is caused by both the variety of processes occurring depositionally and their high susceptibility to diagenetic alterations. In order to fully characterise the behaviour of carbonate rocks in the subsurface is it important to understand their textural heterogeneity and also how faulting can modify their textures. Deformation in fault zones causes the petrophysical properties (e.g. porosity, permeability and velocity) to alter from the background values. For example, fracturing in damage zones surrounding faults increase the permeability, creating conduits to fluids, conversely, fault cores often act as barriers, created by pore occluding processes. However, faulting in carbonate rocks is often complicated by their textural variations, leading to a variety of deformation microstructures, and each will create different petrophysical properties. This thesis aims to understand how faulting effects different carbonate rocks and analyse the controls on any alterations to the petrophysical properties (porosity, permeability and velocity) into the fault zones. Alterations to the permeability are important to unravel in order to assess the fluid flow potential and hydraulic properties of a rock. Understanding the alterations to the velocity can help to better image faults at depth and to provide information on their microstructures.

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Rizzo, Roberto Emanuele. "Quantifying fracture patterns : implications for mechanical and transport properties." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=233636.

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Tadokoro, Keiichi. "Physical Properties of Fault Zone in the Postseismic Stage and its Temporal Change." 京都大学 (Kyoto University), 2000. http://hdl.handle.net/2433/181125.

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Maamari, Fadi. "On the structural properties of cominational circuits and their application to fault simulation." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74590.

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A new fault simulation framework is proposed for combinational circuits, supported by a detailed analysis of the complexity of each of the three fault simulation components: fault-free (logic) simulation, explicit simulation of reconvergent fanout stem faults, and critical path tracing within fanout-free regions. The complexity analysis, measured in terms of the number of required gate evaluations, is implementation independent. The new framework achieves a reduction of the complexity of each component at both the static (input vector independent) level and the dynamic (input vector dependent) level.
At the static level, structural properties determined by a reconvergent fanout analysis are used to reduce the explicit simulation of fanout stem faults. At the dynamic level, dependencies between fault detectabilities are identified and used to reduce both the critical path tracing and explicit simulation components. In addition, fault-free simulation is reduced by tracking areas outside of which it is not required. The dynamic analysis reduces the fault simulation even further through a selective choice of the order in which the three simulation components are performed.

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Al-Hinai, Suleiman Mohammed. "Multi-phase fluid flow properties of fault rocks : implication for production simulation models." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581870.

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It is becoming increasingly common practise to model the impact of faults on fluid flow within petroleum reservoirs by applying transmissibility multipliers, calculated from the single-phase permeability of fault rocks, to the grid-blocks adjacent to faults in produc- tion simulations. The multi-phase flow properties (e.g. relative permeability and capillary pressure) of fault rocks are not considered because special core analysis has never previ- ously been conducted on fault rock samples. The principle aim of this thesis is to fill this knowledge gap. Two distinct approaches have been adopted. First, a considerable num- ber of experiments have been conducted to measure the multi-phase flow properties of faults. The measurements represent different type of fault rocks: cataclastic fault rocks, and fault rocks in impure sandstone; significant amount of effort was needed to evaluate and design new experimental methods. Second, an attempt has also been made to numer- ically model the multi-phase flow behaviour of fault rocks; several numerical techniques (lattice Boltzmann method, pore scale network modelling) have been used. In addition, production simulation modelling has been conducted to investigate the implications of the results. The relative permeability measurements were made using a gas pulse-decay technique on samples whose water saturation was varied using vapour chambers. The measurements indicate that if the same cataclastic fault rocks were present in gas reservoirs from the southern Permian Basin they would have k,.g values of < 0.02. Such large reduction in gas effective permeability was also seen for tight gas sandstones and siltstones. However, the steady-state oil relative permeability measurements for a kaolin rich sample which represents an analogue to fault in impure sandstone was found to be higher then those for the cataclastic fault rocks. The samples studied show also different sensitivity to effective stress. The gas relative permeability measurements proved far more stress sensitive than the single phase permeability values. Pore scale network models have a strong capability in modelling the relative permeability and capillary pressure curves for such low permeability rocks. The predicted results by the model were in good agreement with the experimental data presented in this work. Similarly, lattice Boltzmann method found to have a strong capability for modelling the multi-phase fluid flow in a variety of situation.

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Padgett, Benjamin David. "Modeling and simulation of fault tolerant properties of quantum-dot cellular automata devices." CardinalScholar 1.0, 2010. http://liblink.bsu.edu/uhtbin/catkey/1569024.

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I present a theoretical study of fault tolerant properties in Quantum-dot Cellular Automata (QCA) devices. The study consists of modeling and simulation of various possible manufacturing, fabrication and operational defects. My focus is to explore the effects of temperature and dot displacement defects at the cell level of various QCA devices. Results of simple devices such as binary wire, logical gates, inverter, cross-over and XOR will be presented. A Hubbard-type Hamiltonian and the inter-cellular Hartree approximation have been used for modeling the QCA devices. Random distribution has been used for defect simulations. In order to show the operational limit of a device, defect parameters have been defined and calculated. Results show fault tolerance of a device is strongly dependent on the temperature as well as on the manufacturing defects.
Cell design -- Basic logic gates -- The exclusive or gate.
Department of Physics and Astronomy

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Hay, Karen June. "A proof methodology for verification of real-time and fault-tolerance properties of distributed programs." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186261.

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From the early days of programming, the dependability of software has been a concern. The development of distributed systems that must respond in real-time and continue to function correctly in spite of hardware failure have increased the concern while making the task of ensuring dependability more complex. This dissertation presents a technique for improving confidence in software designed to execute on a distributed system of fail-stop processors. The methodology presented is based on a temporal logic augmented with time intervals and probability distributions. A temporal logic augmented with time intervals, Bounded Time Temporal Logic (BTTL), supports the specification and verification of real-time properties such as, "The program will poll the sensor every t to T time units." Analogously, a temporal logic augmented with probability distributions, Probabilistic Bounded Time Temporal Logic (PBTTL), supports reasoning about fault-tolerant properties such as, "The program will complete with probability less than or equal to p", and a combination of these properties such as, "The program will complete within t and T time units with probability less than or equal to p." The syntax and semantics of the two logics, BTTL and PBTTL, are carefully developed. This includes development of a program state model, state transition model, message passing system model and failure system model. An axiomatic program model is then presented and used for the development of a set of inference rules. The inference rules are designed to simplify use of the logic for reasoning about typical programming language constructs and commonly occurring programming scenarios. In addition to offering a systematic approach for verifying typical behaviors, the inference rules are intended to support the derivation of formulas expressing timing and probabilistic relationships between the execution times and probabilities of individual statements, groups of statements, message passing and failure recovery. Use of the methodology is demonstrated in examples of varying complexity, including five real-time examples and four combined real-time and fault-tolerant examples.

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Jeanne, Pierre. "Architectural, petrophysical and hydromechanical properties of fault zones in fractured-porous rocks : compared studies of a moderate and a mature fault zones (France)." Nice, 2012. http://www.theses.fr/2012NICE4016.

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Bien que les zones de failles représentent un très petit volume de la croute terrestre, elles influencent grandement ses propriétés hydromécaniques. Ce travail compare des analyses multidisciplinaires, de hautes précisions, de deux zones de failles aux propriétés contrastées : l’une est une zone de failles mature de plusieurs kilomètres de long, l’autre s’étend seulement sur quelques centaines de mètres. Leurs propriétés architecturales, hydromécaniques et de résistance mécanique ont été caractérisées dans le but d’améliorer la compréhension des couplages entre l’évolution de leurs propriétés hydromécaniques et leur potentiel de réactivation. Un protocole de caractérisation in-situ des propriétés hydrauliques et mécaniques a été mis au point. Il intègre des analyses microstructurales, des descriptions détaillées des propriétés pétrophysiques à plusieurs échelles. Les deux zones de failles étudiées montrent toutes deux des relations entre leurs histoires diagénétiques, les propriétés initiales des formations sédimentaires et leurs propriétés actuelles hydromécaniques. Il a été mis en évidence que le paramètre le plus important gouvernant le comportement hydromécanique des zones de failles est la continuité de sa zone d’endommagement. Une zone de failles mature aura une zone d’endommagement relativement continue alors qu’une zone de failles non-mature aura une zone d’endommagement hétérogène caractérisée par une alternance de niveaux fracturés et non-fracturés. Ces contrastes architecturaux dépendent des propriétés initiales de la roche intacte. Au sein de la série sédimentaire, les variations de la résistance à la compression (σc) de la roche intacte induisent différents mécanismes d’accommodations des déformations. Il en résulte une architecture de zone de failles présentant de fortes variations d’épaisseur, caractérisée par une alternance de niveaux très perméables et très déformables avec des niveaux imperméables et peu déformables
Although fault zones represent a very small volume of the crust, they highly influence the crust’s mechanical and fluid flows properties. This work compares high definition trans-disciplinary analyses of two fault zones with highly contrasted properties. One is a mature fault zone of plurikilometer length, and the other is a small fault zone of a few hundred meters length. We have characterized the architectural, hydromechanical and strength properties of these faults to improve the understanding of the coupling between fault zones hydromechanical properties and their potential activation. A protocol to characterize in the field (on outcropping segments) the faults hydraulic and mechanical properties has been conducted through the coupling of micro-structural analyses, detailed rock physical descriptions at the rock mass several scales. The two studied fault zones despite their different sizes display some similarities. Both show a strong coupling between the fault zone diagenetic history, the initial properties of the sedimentary layers and the fault zone current hydraulic and mechanical properties. We show that the most important parameter governing the hydromechanical behaviors of fault zones is the continuity of the damage zones. A mature fault zone will have a relatively continuous damage zone while a small fault zone will contain a more heterogeneous damage zone characterized by an alternation of fractured and un-fractured layers. These architectural contrasts of damage zones also depend on the initial intact rock properties of the sedimentary series. Contrasted initial intact rock strengths (σc) induce contrasted strain accommodation mechanisms in the fault zone compartments, and an associated fault zone architecture that displays large thickness variations, characterized by alternate high-permeable-low-stiff and low-permeable-high-stiff layers in the damage zone

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Tueckmantel, Christian. "Fluid flow properties and fault zone architecture of large- and small-scale normal fualts." Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531513.

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22

Lindsey, Eric Ostrom. "Fault properties, rheology and interseismic deformation in Southern California from high-precision space geodesy." Thesis, University of California, San Diego, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3721663.

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This dissertation presents the collection and processing of dense high-precision geode- tic data across major faults throughout Southern California. The results are used to inform numerical models of the long-term slip rate and interseismic behavior of these faults, as well as their frictional and rheological properties at shallow depths. The data include campaign surveys of dense networks of GPS monuments crossing the faults, and Interferometric Synthetic Aperture Radar (InSAR) observations from ENVISAT. Using a Bayesian framework, we first assess to what extent these data constrain relative fault slip rates on the San Andreas and San Jacinto faults, and show that the inferred parameters depend critically on the assumed fault geometry. We next look in detail at near-field observations of strain across the San Jacinto fault, and show that the source of this strain may be either deep anomalous creep or a new form of shallow, distributed yielding in the top few kilometers of the crust. On the San Andreas fault, we show that this type of shallow yielding does occur, and its presence or absence is controlled by variations in the local normal stress that result from subtle bends in the fault. Finally, we investigate shallow creep on the Imperial fault, and show that thanks to observations from all parts of the earthquake cycle it is now possible to obtain a strong constraint on the shallow frictional rheology and depth of the material responsible for creep. The results also suggest activity on a hidden fault to the West, whose existence has been previously suggested but never confirmed.

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Krogstad, Randy. "Kinematic Constraints on Tremor and Slow Slip in Cascadia and Implications for Fault Properties." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20720.

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Subduction zone fault processes range from tsunami-generating megathrust events to aseismic creep along the deeper portions of the fault. Episodic tremor and slow slip (ETS) represents the transition between these two regimes, where slip occurs at semi-regular recurrence intervals of months-to-years. These events are also accompanied by low frequency earthquakes, referred to as tremor. The study of ETS in Cascadia has been made possible by the enhancement of large-scale seismic and geodetic networks. In this dissertation, I use a range of geodetic and seismic observations at sub-daily to decadal time scales to investigate the kinematic behavior of individual ETS events, as well as the long-term behavior of the ETS zone and its relationship with the updip seismogenic zone. In Cascadia, current seismic hazard maps use the ETS zone as the downdip limit of rupture during future megathrust events. In Chapter II, I utilize uplift rates derived from 80 years of leveling measurements to explore the possibility that long-term strain accumulation exists near the ETS zone. The uplift rates are consistent with a region of 10-20% locking on the updip side of the ETS zone. The lack of associated topography indicates that the accumulated strain must be released during the megathrust cycle. The correlation of tremor and slip in Cascadia suggests there is an inherent relationship between the two. In Chapter III, I develop a method for using tremor as a proxy for slip to assess the spatial relationship of tremor and slip. I compare predictions of tremor-derived slip models to results from static inversions of GPS offsets by modeling slip based on the density of tremor. These comparisons suggest that the correlation of tremor and slip is variable along strike and along dip. In Chapter IV, I explore how borehole strainmeters can improve our resolution of slip on the plate interface. I incorporate strainmeters into joint, time-dependent kinematic inversions with GPS data. The temporal resolution of strainmeters provides improved constraints when deriving time-dependent slip estimates during slow slip events, allowing us to better image the kinematics of slow slip. This dissertation includes previously published and unpublished material.

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Tanikawa, Wataru. "Transport properties and high-velocity frictional behavior of Chelungpu, Shuangtung and Shuichangliu fault zones and their implication for fault motion during 1999 Chi-Chi earthquake." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144202.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第12119号
理博第3013号
新制||理||1449(附属図書館)
23955
UT51-2006-J114
京都大学大学院理学研究科地球惑星科学専攻
(主査)教授嶋本利彦, 助教授田上高広, 教授平島崇男
学位規則第4条第1項該当

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25

Zhao, Peng. "Seismic velocity contrasts and temporal changes of strike-slip faults in central California." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37242.

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The spatial patterns of bimaterial interfaces along the Parkfield section of the San Andreas Fault (SAF) and central section of the Calaveras Fault are systematically investigated with large data sets of near-fault waveforms. Different from the usage of direct P and S waves in traditional tomographic studies, a particular seismic phase named fault zone head wave (FZHW) is used to image the bimaterial fault interfaces. The results show clear variations of seismic velocities contrast both along-strike and along-depth directions in both regions, which is in general consistent with local geological setting at surface and existing 3D tomography results. In the Parkfield section of SAF, the result of velocity contrast is used to test the relationship between preferred rupture directions of M6 Parkfield earthquakes and bimaterial interface. Strong velocity contrast (~5-10%) near Middle Mountain (MM) could control the rupture directions of nearby earthquakes to SE, such as the case for 1966 M6 Parkfield earthquake. In comparison, weak velocity contrast (~0-2%) near the epicenter of the 2004 Parkfield M6 earthquake (i.e., Gold Hill) probably has no influence on controlling its rupture direction, which is consistent with the bilateral rupture of the 2004 Parkfield earthquake. In the central Calaveras Fault, a detailed analysis of the moveout between FZHWs and direct P waves revealed the existence of a complicated fault structure with velocity contrast increasing from NW to SE of station CCO. The high velocity contrast SE of station CCO could be caused by a low-velocity zone SE of station CCO. The spatio-temporal variations of seismic velocity around the central Calaveras Fault and its nearby region are investigated based on the waveform analysis of 333 repeating clusters following the 1984 ML6.2 Morgan Hill earthquake. Clear reduction of seismic velocity is shown for all repeating clusters immediately after the mainshock, followed by a logarithmic recovery. The coseismic change mostly occurs at shallow layers (top few hundred meters) for the region away from the rupture area of the mainshock, but extends much deeper around the rupture zone of the Morgan Hill earthquake. The estimated depth of the damage zone is up to 6 km in the fault based on the repeating clusters directly beneath station CCO. Finally, temporal changes around the Parkfield section of SAF are studied using recently developed ambient noise cross-correlation technique. The extracted daily empirical Green functions (EGFs) from 0.4-1.3 Hz noise records are used to estimate subtle temporal changes associated with large earthquakes from local to teleseismic distances. The results show clear coseismic reduction of seismic velocities after the 2004 M6 Parkfield earthquake, similar to the previous observation based on repeating earthquakes. However, no systematic changes have been detected for other four regional/teleseismic events that have triggered clear tremor activity in the same region. These results suggest that temporal changes associated with distance sources are very subtle or localized so that they could not be detected within the resolution of the current technique (~0.2%).

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Keighley, Bradbury Kelly. "Rock Properties and Structure Within the San Andreas Fault Observatory at Depth (SAFOD) Borehold, Northwest of Parkfield, California: In Situ Observations of Rock Deformation Processes and Fluid-Rock Interactions of the San Andreas Fault Zone at ~ 3 km Depth." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1410.

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This project examines the composition, structure, and geophysical properties of rocks sampled within the San Andreas Fault Observatory at Depth (SAFOD) borehole drilling experiment near Parkfield, California. Cuttings, sidewall cores, spot-core, and whole-rock core are examined from the meso- to micro-scale to characterize the nearfault environment at shallow crustal levels (0-4 km) along the central segment of the San Andreas fault. The central segment deforms by contiuous aseismic creep and microseismicity. An integrated approach utilizing core-logging, detailed structural core mapping, petrology, microstructural analyses, whole-rock geochemistry, borehole geophysics, and analog field studies is followed. At SAFOD, fractured granitic rocks and arkosic sediments are identified west of the San Andreas fault zone on the Pacific Plate; whereas sheared fine-grained sediments, ultrafine black fault-related rocks, and serpentinite-bearing fault gouge are present within and northeast of the fault zone on the North American Plate. Here, the fault consists of a broad zone of variably damaged rock containing localized zones of highly concentrated shear that often juxtapose distinct rock-types. Two zones of serpentinite-bearing clay gouge, each meters-thick are found in two locations where active aseismic creep was identified in the borehole. The gouge is composed of Mg-rich clays, serpentinite (lizardite ± chrysotile) with notable increases in magnetite, and Fe-, Ni-, and Cr-oxides/hydroxides and Fe-sulfides relative to the surrounding host rock. Organic carbon is locally high within fractures and bounding slip surfaces. The rocks adjacent to and within the two gouge zones display a range of deformation including intensely fractured regions, blockin- matrix fabrics, and foliated cataclasite structure. The blocks and clasts predominately consist of competent sandstone and siltstone embedded in a clay-rich matrix that displays a penetrative scaly fabric. Mineral alteration, veins, fracture-surface coatings, and slickelined surfaces are present throughout the core, and reflect a long history of syndeformation and fluid-rock reaction that contributes to the low-strength and creep in the meters-thick gouge zones. Evaluation of borehole geophysical data and elastic modulii for the lithologic and structural units identified in the SAFOD Phase 3 core reveal a correlation between composition and textures and the structural and/or permeability architecture of the SAF at SAFOD. Highly reduced velocity and elastic modulii surround the two serpentinitev bearing gouge zones, the Buzzard Canyon fault to the southwest, and another bounding fault to the northeast. Velocity and elastic moduli values on the Pacific Plate or southeast of the active fault trace intersected by SAFOD are much higher relative to the values measured on the North American Plate, or northeast of the fault trace. Within and adjacent to the two active gouge zones, the rock properties are highly variable over short distances, however, they are significantly lower relative to material outside of the fault zones. This research contributes critical evidence for rock properties and slip behavior within an active plate boundary fault. Results from this research and the SAFOD experiment help to constrain numerous hypotheses related to fault zone behavior and earthquake generation within central California.

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Park, Kibog. "Electronic properties of stacking-fault induced heterostructures in silicon carbide studied with ballistic electron emission microscopy." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149089614.

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28

Cook, Becky J. "Along and across strike variations in the structure, material and fault properties of the Sumatran Subduction Zone." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/374820/.

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Earthquake ruptures offshore of north-central Sumatra in 2004 (Sumatra-Andaman segment) and 2005 (Nias segment) exhibited variable shallow slip behaviour that is well resolved by tsunami, seismologic, and geodetic observations. Closely spaced 2D MCS profiles collected covering these rupture segments, the segment to the south (Mentawai segment), and the segment boundaries allow an unprecedented opportunity to study the detailed along- and across-strike variation in the structure and properties of the wedge and plate boundary that may be related to the variable shallow slip behaviour. The large tsunami generated by the 2004 earthquake is thought to have been the result of unexpected shallow slip on the shallow plate boundary of the southern Sumatra-Andaman segment; whereas in the Nias segment the shallow plate boundary showed evidence of significant afterslip and the 2005 earthquake did not generate a significant tsunami. In the northern Mentawai segment, Batu Segment Boundary Zone, and southern Nias segment the shallow plate boundary is relatively weak and the weakened plate boundary is likely related to dehydration reaction occurring below the frontal prism and potential fluid flow focussing on basement topographic highs. In these areas, imbricate faulting in the frontal prism occurs along landward and/or seaward dipping faults. At the mid-slope break, the slip rate along these imbricate faults, formed in the frontal prism, decreases and they are potentially crosscut by out-of-sequence faults. In the southern Sumatra-Andaman segment, our findings of a relatively strong plate boundary fault are consistent with increased compaction and early dehydration of material within the thick incoming section which strengthens the incoming section and results in a potentially seismogenic shallow plate boundary. The accretionary prism here is characterised by an unusual prism profile with a narrow steep toe and broad flat plateau. We propose that the steep prism toe is built up by coeval faulting on both seaward and landward dipping faults. At the break in slope, underplating becomes the dominant prism and the transition from frontal accretion to underplating contributes to the development of the unusual prism geometry. Within our study area, we find that there is significant variability in the frictional strength of the shallow plate boundary and mechanisms of accretion, which can be correlated with the geometry and faulting within the prism. We show that these changes are related to a combination of subducting plate topography, trench sedimentation rates, overall sediment thickness and sediment/fault permeability.

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Aubert, Irène. "Fault zone structural and diagenetic evolution in carbonates : impact on reservoir properties (urgonian case study, SE France)." Thesis, Aix-Marseille, 2020. http://www.theses.fr/2020AIXM0175.

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Les zones de failles ont un impact important sur les réservoirs carbonatés car elles peuvent agir comme des drains ou des barrières en fonction de leurs propriétés structurales et diagénétiques. Il est important de bien comprendre ces propriétés pour déterminer les caractéristiques hydrauliques des zones de failles. Pour cela, l'approche multidisciplinaire de cette thèse combinant l’analyse structurale, diagénétique et géochimique vise à (1) contraindre l'évolution structurale et diagénétique des zones de failles dans les carbonates, (2) établir des règles et des concepts géométriques permettant de construire des modèles géologiques cohérents, et (3) permettre une meilleure compréhension de la réponse dynamique hydraulique des zones de failles dans les carbonates à travers leurs évolutions. Nous avons étudié 3 zones de failles (Castellas, D19) affectant les carbonates de plate-forme du Barrémien inférieur (faciès Urgonien) situées dans l'anticlinal de La Fare et dans celui de la Nerthe (Provence - SE France). Ces travaux ont permis de restaurer les séquences diagénétiques des zones de failles avec des analyses de ciment sous catholuminescence et des mesures des isotopes 13C et 18O. L'analyse structurale a permis de compléter l'évolution diagénétique en déterminant les caractéristiques architecturales liées à chaque activité de faille et en discriminant l'effet des structures préexistantes sur le développement ultérieur de ces dernières. Enfin, cette étude a permis d'améliorer notre compréhension du comportement hydraulique des zones de failles dans les carbonates au cours temps
Fault zones strongly impact carbonates reservoir properties as they can act as drains or barriers depending of their structural and diagenetic properties. Hence, it is important to have an integrativecomprehension of these properties that affect the fault zones hydraulic properties. To this end, the multidisciplinary approach of this thesis combining structural, diagenetic and geochemical approaches aims to (1) constrain the structural and diagenetic evolution of fault zones in carbonates (2) draw rules and geometrical concepts allowing building of coherent geological models, and (3) allow a better understanding of the hydraulic dynamic response of fault zones in carbonates through their evolutions. We studied 3 fault zones (Castellas, D19) affecting lower Barremian platform carbonates (Urgonian facies) located in La Fare and Nerthe anticlines (Provence – SE France). This work allowed the restoration of fault zones diagenetic sequences with cement analyses under catholuminescence and 13C and 18O isotopes. The structural analysis completed the diagenetic evolution by determining the architectural characteristics related to each fault activity and discriminating the effect of pre-existing structures on subsequent fault development. Finally, this study improved our understanding of fault zones hydraulic behaviour in carbonates through times

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30

Wang, Lei [Verfasser]. "Pressure-dependent mechanical and acoustic properties of porous sandstones and laboratory injection-induced fault slip within porous sandstones / Lei Wang." Berlin : Freie Universität Berlin, 2021. http://d-nb.info/1236573110/34.

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31

Hamada, A. S. (Atef Saad). "Manufacturing, mechanical properties and corrosion behaviour of high-Mn TWIP steels." Doctoral thesis, University of Oulu, 2007. http://urn.fi/urn:isbn:9789514285844.

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Abstract Austenitic high-Mn (15–30 wt.%) based twinning-induced plasticity (TWIP) steels provide great potential in applications for structural components in the automotive industry, owing to their excellent tensile strength-ductility property combination. In certain cases, these steels might also substitute austenitic Cr-Ni stainless steels. The aim of this present work is to investigate the high-temperature flow resistance, recrystallisation and the evolution of microstructure of high-Mn steels by compression testing on a Gleeble simulator. The influence of Al alloying (0–8 wt.%) in the hot rolling temperature range (800°C–1100°C) is studied in particular, but also some observations are made regarding the influence of Cr alloying. Microstructures are examined in optical and electron microscopes. The results are compared with corresponding properties of carbon and austenitic stainless steels. In addition, the mechanical properties are studied briefly, using tension tests over the temperature range from -80°C to 200°C. Finally, a preliminary study is conducted on the corrosion behaviour of TWIP steels in two media, using the potentiodynamic polarization technique. The results show that the flow stress level of high-Mn TWIP steels is considerably higher than that of low-carbon steels and depends on the Al concentration up to 6 wt.%, while the structure is fully austenitic at hot rolling temperatures. At higher Al contents, the flow stress level is reduced, due to the presence of ferrite. The static recrystallisation kinetics is slower compared to that of carbon steels, but it is faster than is typical of Nb-microalloyed or austenitic stainless steels. The high Mn content is one reason for high flow stress as well as for slow softening. Al plays a minor role only; but in the case of austenitic-ferritic structure, the softening of the ferrite phase occurs very rapidly, contributing to overall faster softening. The high Mn content also retards considerably the onset of dynamic recrystallisation, but the influence of Al is minor. Similarly, the contribution of Cr to the hot deformation resistance and static and dynamic recrystallisation, is insignificant. The grain size effectively becomes refined by the dynamic and static recrystallisation processes. The tensile testing of TWIP steels revealed that the Al alloying and temperature have drastic effects on the yield strength, tensile strength and elongation. The higher Al raises the yield strength because of the solid solution strengthening. However, Al tends to increase the stacking fault energy that affects strongly the deformation mechanism. In small concentrations, Al suppresses martensite formation and enhances deformation twinning, leading to high tensile strength and good ductility. However, with an increasing temperature, SFE increases, and consequently, the density of deformation twins decreases and mechanical properties are impaired. Corrosion testing indicated that Al alloying improves the corrosion resistance of high-Mn TWIP steels. The addition of Cr is a further benefit for the passivation of these steels. The passive film that formed on 8wt.% Al-6wt.%Cr steel was found to be even more stable than that on Type 304 steel in 5–50% HNO3 solutions. A prolonged pre-treatment of the steel in the anodic passive regime created a thick, protective and stable passive film that enhanced the corrosion resistance also in 3.5% NaCl solution.

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Büchler, Matthias [Verfasser], Alexander [Akademischer Betreuer] Pretschner, and Robert [Akademischer Betreuer] Hierons. "Semi-Automatic Security Testing of Web Applications with Fault Models and Properties / Matthias Büchler. Betreuer: Alexander Pretschner. Gutachter: Alexander Pretschner ; Robert Hierons." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1093793147/34.

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Bayoudh, Mehdi. "Active Diagnosis of Hybrid Systems Guided by Diagnosability Properties - Application to Autonomous Satellites." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT069H.

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Motivée par les besoins du domaine spatial en termes de diagnostic embarqué et d’autonomie, cette thèse s’intéresse aux problèmes de diagnostic, de diagnosticabilité et de diagnostic actif des systèmes hybrides. Un formalisme hybride est proposé pour représenter les deux dynamiques, continues et discrètes, du système. En s’appuyant sur ce modèle, une approche de diagnostic passif est proposée en mariant les techniques des systèmes à événements discrets et des systèmes continus. Un cadre formel pour la diagnosticabilité des systèmes hybrides a également été établi proposant des définitions et des critères pour la diagnosticabilité hybride. Suite à un diagnostic passif ambigu, le diagnostic actif est nécessaire afin de désambiguïser l’état du système. Cette thèse propose donc une approche de diagnostic actif, qui partant d’un état de croyance incertain, fait appel aux propriétés de diagnosticabilité du système pour déterminer la configuration où les fautes peuvent être discriminées. Une nouvelle machine à états finis appelée diagnostiqueur actif est introduite permettant de formaliser le diagnostic actif comme un problème de planification conditionnelle. Un algorithme d’exploration de graphes ET-OU est proposé pour calculer les plans de diagnostic actif. Finalement, l’approche de diagnostic a été testée sur le Système de Contrôle d’Attitude (SCA) d’un satellite de Thales Alenia Space. Le module de diagnostic a été intégré dans la boucle fermée de commande. Des scénarios de faute ont été testés donnant des résultats très satisfaisants
Motivated by the requirements of the space domain in terms of on-board diagnosis and autonomy, this thesis addresses the problems of diagnosis, diagnosability and active diagnosis of hybrid systems. Supported by a hybrid modeling framework, a passive approach for model-based diagnosis mixing discrete-event and continuous techniques is proposed. The same hybrid model is used to define the diagnosability property for hybrid systems and diagnosability criteria are derived. When the diagnosis provided by the passive diagnosis approach is ambiguous, active diagnosis is needed. This work provides a method for performing such active diagnosis. Starting with an ambiguous belief state, the method calls for diagnosability analysis results to determine a new system configuration in which fault candidates can be discriminated. Based on a new finite state machine called the diagnoser, the active diagnosis is formulated as a conditional planning problem and an AND-OR graph exploration algorithm is proposed to determine active diagnosis plans. Finally, the diagnosis approach is tested on the Attitude Control System (ACS) of a satellite simulator provided by Thales Alenia Space. The diagnosis module is successfully tested on several fault scenarios and the obtained results are reported

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Chu, Hoang-Nam. "Test et évaluation de la robustesse de la couche fonctionnelle d'un robot autonome." Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2011INPT0054/document.

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La mise en oeuvre de systèmes autonomes nécessite le développement et l'utilisation d'architectures logicielles multi-couches qui soient adaptées. Typiquement, une couche fonctionnelle renferme des modules en charge de commander les éléments matériels du système et de fournir des services élémentaires. Pour être robuste, la couche fonctionnelle doit être dotée de mécanismes de protection vis-à-vis de requêtes erronées ou inopportunes issues de la couche supérieure. Nous présentons une méthodologie pour tester la robustesse de ces mécanismes. Nous définissons un cadre général pour évaluer la robustesse d'une couche fonctionnelle par la caractérisation de son comportement vis-à-vis de requêtes inopportunes. Nous proposons également un environnement de validation basé sur l'injection de fautes dans le logiciel de commande d'un robot simulé. Un grand nombre de cas de tests est généré automatiquement par la mutation d'une séquence de requêtes valides. Les statistiques descriptives des comportements en présence de requêtes inopportunes sont analysées afin d'évaluer la robustesse du système sous test
The implementation of autonomous systems requires the development and the using of multi-layer software architecture. Typically, a functional layer contains several modules that control the material of the system and provide elementary services. To be robust, the functional layer must be implemented with protection mechanisms with respect to erroneous or inopportune requests sent from the superior layer. We present a methodology for robustness testing these mechanisms. We define a general framework to evaluate the robustness of a functional layer by characterizing its behavior with respect to inappropriate requests. We also propose an validation environment based on fault injection in the control software of a simulated robot. A great number of test cases is generated automatically by the mutation of a sequence of valid requests. The descriptive statistics of the behaviors in the presence of inappropriate requests are analyzed in order to evaluate the robustness of the system under test

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Lefèvre, Mélody. "Propriétés structurales, pétro-physiques et circulations de fluides au sein d'une zone de failles dans les argiles." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4320/document.

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Les zones de failles concentrent la migration de fluides et la déformation dans la croûte supérieure. Les propriétés hydrauliques des formations argileuses en font des excellents sites de stockage et des roches mères performants. Les zones de failles peuvent jouer deux rôles contraires dans la circulation de fluides, soit elles s’expriment sous forme de drains, soit elles constituent une barrière, et souvent les deux rôles sont combinés au sein d’une même zone de failles. Les processus de migration des fluides dans les zones de failles affectant les argiles sont peu connus. Cette étude s’est focalisée sur la structure, les paléo-circulations, les circulations actuelles lors de tests d’injection et les propriétés pétro-physiques de la zone de failles présente dans le laboratoire de recherche souterrain de Tournemire dans les argilites Toarciennes. La structure de la zone de failles a été caractérisée par des forages et reconstituée en 3D par modélisation numérique, permettant de définir des faciès de déformation. L’architecture de la zone de failles se caractérise par une imbrication de facies de déformations plus ou moins intenses sans claire organisation en cœur et zone endommagée comme observée dans les roches plus dures. Les zones intactes, fracturées et les brèches sont respectivement caractérisées par des porosités matricielles comprises entre 9.5-13.5, 10-15 et 13-21%. La circulation de fluide se concentrant aux limites de la brèche et au niveau des zones de failles «immatures» ou secondaires comprises dans les zones fracturées. Lors de son activité, la zone de failles a déjà été affectée par au moins deux phases de circulations de fluides
Fault zones concentrate fluids migration and deformations in the upper crust. The shale hydraulic properties make them excellent storage sites and hydrocarbon reservoirs/source rocks. Fault zones can play two roles in the fluid circulation; drains or barriers, in general, both roles are combined within the same fault zone. What are the conditions that promote the fluid circulation along the fault zones in shales and what are the fault zone impacts on the formation properties are relatively poorly explored key questions. This study focused on characterizing the relationships between fault architecture, paleo-fluid as well as current fluid circulations through the analysis of fault calcite mineralization, injection tests and petrophysical properties conducted on a fault zone outcropping underground in the Tournemire research laboratory nested in the Toarcian shale. The fault zone structure was characterized using boreholes data and reconstructed in 3D through modeling to define different deformation facies. No clear facies organization is observed, a fault core and a fault damage zone being difficult to define as it is in hard rocks. The intact, fractured and breccia facies are characterized by a porosity of 9.5-13.5, 10-15 and 13-21%. Large fluid flowrate concentrated along a few “channels” located at the breccia boundaries and in the secondary fault zones that displayed fractured facies and limited breccia fillings. Detailed microstructural and geochemical analysis at the breccia/fractured zones interface revealed that fluids circulated out of the main shear zones, in micro-more or less inherited fractures highlighting a decoupling between fault slip and fluid migrations

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Reyer, Dorothea [Verfasser], Sonja L. [Akademischer Betreuer] Philipp, Martin [Akademischer Betreuer] Sauter, and Rüdiger [Akademischer Betreuer] Thomas. "Outcrop analogue studies of rocks from the Northwest German Basin for geothermal exploration and exploitation : Fault zone structure, heterogeneous rock properties, and application to reservoir conditions / Dorothea Reyer. Gutachter: Sonja L. Philipp ; Martin Sauter ; Rüdiger Thomas. Betreuer: Sonja L. Philipp." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/105928362X/34.

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37

Barbosa, Fabio Rocha. "DiagnÃstico de Falhas Incipientes a Partir das Propriedades FÃsico-QuÃmicas do Ãleo Isolantes em Transformadores de PotÃncia Como MÃtodo Alternativo Ã AnÃlise de Gases Dissolvidos." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9189.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
O diagnÃstico de falhas incipientes em transformadores de potÃncia imersos em Ãleo estÃ diretamente relacionado Ã avaliaÃÃo das condiÃÃes do sistema de isolamento. Este estudo aborda a relaÃÃo entre os gases dissolvidos no Ãleo e a qualidade do Ãleo mineral isolante utilizado em transformadores de potÃncia. As redes neurais artificiais sÃo utilizadas na abordagem da avaliaÃÃo das condiÃÃes operacionais do Ãleo isolante em transformadores de potÃncia, que Ã caracterizada por um comportamento dinÃmico nÃo-linear. As condiÃÃes de operaÃÃo e a integridade do sistema de isolamento de um transformador de potÃncia podem ser inferidas atravÃs das anÃlises fÃsico-quÃmicas e cromatogrÃficas (AnÃlise de GÃs Dissolvido). Estes ensaios permitem estabelecer procedimentos de operaÃÃo e manutenÃÃo do equipamento e normalmente sÃo realizados simultaneamente. Esta tese de doutorado propÃe um mÃtodo que pode ser usado para extrair informaÃÃes cromatogrÃficas usando as anÃlises fÃsico-quÃmicas atravÃs de redes neurais artificiais. As anÃlises atuais das propriedades fÃsico-quÃmicas fornecem apenas diagnÃstico do estado do Ãleo, o que nÃo permite o diagnÃstico de falhas incipientes. Acredita-se que, as concessionÃrias de energia podem melhorar a confiabilidade na previsÃo de falhas incipientes a um custo menor com este mÃtodo, uma vez que apenas um ensaio Ã necessÃrio. Os resultados mostraram que esta estratÃgia Ã promissora com mÃdia de acertos em diagnÃsticos de falhas maiores que 72%. O objetivo deste trabalho Ã a aplicaÃÃo direta do diagnÃstico de falhas incipientes atravÃs da utilizaÃÃo de propriedades fÃsico-quÃmicas, sem a necessidade de fazer uma cromatografia do Ãleo.
The diagnosis of incipient fault in power transformers immerses in oil are directly related to the assessment of the isolation system conditions. This search is about the relationship between dissolved gases and the quality of the insulating mineral oil used in power transformers. Artificial Neural Networks are used to approach operational conditions assessment issue of the insulating oil in power transformers, which is characterized by a nonlinear dynamic behavior. The operation conditions and integrity of a power transformer can be inferred by analysis of physicochemical and chromatographic (DGA â Dissolved Gas Analysis) profiles of the isolating oil. This tests allow establishing procedures for operating and maintaining the equipment and usually are performed simultaneously. This work proposes a method that can be used to extract chromatographic information using physicochemical analysis through Artificial Neural Networks. The present analysis of physicochemical properties only provide a diagnostic tool for the oil quality, which does not allow the diagnosis of incipient faults. ItÂs believed that, the power utilities could improve reliability in the prediction of incipient failures at a lower cost with this method, since only one test is required. The results show this strategy might be promising with an average accuracy for diagnosis of faults greater than 72%. The purpose of this work is the direct implementation of the diagnosis of incipient faults through the use of physicochemical properties without the need to make an oil chromatography.

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38

Smith, Steven A. F. "The internal structure, mechanics, and fluid flow properties of low-angle normal faults : a case study from the island of Elba, Italy." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/2091/.

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Low-angle normal faults have been extensively documented in areas of regional extension, in both continental and oceanic lithosphere, but their existence as seismically active structures remains controversial. Low-angle normal faults do not conform to 'traditional’ frictional fault theory, and large earthquakes on low-angle normal faults appear to be rare. Their enigmatic nature suggests that they may hold important clues regarding the rheology of fault zones in general, controls on frictional behaviour, and the deformation histories of the mid- to upper-crust. In this study, I investigate the internal structure, mechanical properties, and fluid flow conditions along a large-displacement low-angle normal fault exposed on the Island of Elba, Italy. Using field relationships, microstructural analysis, stable isotope geochemistry, and rock deformation experiments, I document the most important characteristics of the fault zone, and test hypotheses concerning the mechanical behaviour and evolution of low-angle normal faults. The Zuccale low-angle normal fault crosscuts and displaces a lithologically heterogeneous sequence of wall rocks. Field relationships suggest that it was active in the upper crust during the emplacement of large plutonic complexes. On a regional-scale, the Zuccale fault appears to have a long-wavelength domal morphology, which may have resulted from the intrusion of an upper-crust igneous pluton in to the shallow footwall of the fault. Pluton intrusion strongly influenced the fluid flow regimes and fault rock evolution along the Zuccale fault. Geometric and kinematic relationships between the Zuccale fault and a network of minor footwall faults suggest that the Zuccale fault slipped at a low-angle throughout most of its history. The footwall faults were active broadly contemporaneously with movement along the Zuccale fault, and controlled the distribution and connectivity of different fault rock components. This imparted a distinct mechanical structure to the fault core, potentially influencing fault zone rheology. The central core of the Zuccale fault contains a sequence of fault rocks that deformed by a variety of deformation mechanisms, and formed during progressive exhumation of the fault zone. Triaxial deformation experiments indicate that the frictional strength of many of the fault rocks is too high to explain slip along the Zuccale fault. However, several potential mechanisms of fault zone weakening have been identified, including fluid-assisted dissolution-precipitation creep, grain-size sensitive creep in calcite mylonites, frictional sliding within phyllosilicate-rich areas of the fault core, high fluid pressures, and particulate flow accommodated by fine-grained clay minerals. Fluids associated with the Zuccale fault were derived from two main sources. During the relatively early stages of movement, and particularly during the intrusion of plutonic complexes, fluids were of meteoric-hydrothermal origin. During the late stages of exhumation, fluids were derived from a seawater source that infiltrated downwards through faulted and fractured wall rocks. Sub-horizontal tensile veins carrying both fluid signatures are found adjacent to and within the fault core, suggesting that supra-lithostatic fluid pressures were able to develop throughout the exhumation history. One of the consequences of high fluid pressures was the development of a suite of fluidized fault breccias, a newly recognized type of fault rock that may be indicative of the interseismic stage of the earthquake cycle.

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39

O'Malley, Matthew John. "A Structural, Bonding, and Properties Study of the Ordered Rock Salt Structures Li₂MO₃ (M = Ru, Ir, Pt)." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250526178.

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40

Taverna, Joël. "Modélisation mécanique des déformations de la lithosphère." Grenoble 1, 1998. http://www.theses.fr/1998GRE10084.

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Les objectifs de cette these sont de decrire les mecanismes de deformations de la lithosphere en regime compressif, et le controle impose par les parametres mecaniques sur la maniere dont le raccourcissement horizontal est accommode (par la formation de plis, de chevauchements, ou encore par epaississement homogene). Nous avons etudie la nature des instabilites susceptibles de se developper en utilisant des calculs analytiques bases sur la resolution des equations de navier-stokes ainsi que leur evolution pour des taux de deformation importants a partir de modeles analogiques et de calculs numeriques par la methode des elements finis. Les calculs analytiques ont permis de determiner l'influence des differents parametres mecaniques de la lithosphere sur le developpement d'instabilites. En domaine oceanique, le raccourcissement est essentiellement accommode par la formation de plis affectant l'ensemble de la lithosphere. Les parties fragiles de la lithosphere et les contrastes de densite controlent la croissance des instabilites. Deux series d'experiences analogiques ont ensuite permis de confirmer les resultats precedents et d'etudier l'evolution tridimensionnelle d'instabilites lithospheriques apres l'apparition de la fracturation. En domaine continental, le passe tectonique et les heterogeneites mecaniques qui en resultent joue un role essentiel pour l'initiation des plis. Les heterogeneites initiales peuvent favoriser l'apparition de failles aux depends des plis de grandes longueurs d'onde puis la subsidence des portions de lithosphere ainsi delimitees. Les structures ainsi formees s'apparentent a des bassins compressifs. Leur longueur d'onde reste cependant controlee en partie par celle des plis lithospheriques. Ces resultats ont ete completes par des calculs numeriques bases sur la methode des elements finis. Les plis ne se developpent qu'apres plastification complete des parties fragiles de la lithosphere oceanique ou continentale.

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41

Prilliman, Gerald Stephen. "Synchrotron X-ray diffraction studies of phase transitions and mechanical properties of nanocrystalline materials at high pressure." Berkeley, Calif. : Oak Ridge, Tenn. : Lawrence Berkeley National Laboratory ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/825137-DcNEaM/native/.

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Thesis (Ph.D.); Submitted to The University of California at Berkeley, Berkeley, CA (US); 1 Sep 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "LBNL--55022" Prilliman, Gerald Stephen. USDOE Director. Office of Science. Office of Basic Energy Sciences (US) 09/01/2003. Report is also available in paper and microfiche from NTIS.

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42

Kremer, Yannick. "Deriving field-based statistical relationships to characterize the geometry, heterogeneity and permeability of faults in mixed sand-shale sequences : a new tool for upscaling flow properties." Thesis, University of Strathclyde, 2014. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=25706.

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Fault zones can strongly affect fluid flow in the subsurface. Faults can act as (partial) barriers to flow, as conduits and as combined conduit-barrier systems. Understanding the relationship between faulting and fluid flow has many practical applications, including hydrocarbon exploration and production, mineral exploration, groundwater management, radioactive waste disposal, geothermal energy and carbon sequestration. This study is primarily focussed at the applications in the hydrocarbon industry. For hydrocarbon exploration, faults are important because they can act as long term barriers (fault sealing), in which case they can be part of structural traps. Faults acting as conduits also need to be considered, hydrocarbons moving vertically along a fault can either migrate into a reservoir, or the hydrocarbons can leak out of the reservoir along the fault. For hydrocarbon production also the short term effect of faults needs to be considered, as faults can block or baffle flow towards a well. For all these scenarios it is currently diffcult to reliably predict the behaviour of the fault deep underground. The research presented in this thesis aims to improve this prediction. Several studies have shown that fluid flow along and across fault zones is strongly affected by the heterogeneity of the fault zone and the presence of connected high permeability pathways. Both heterogeneity and high permeability pathways cannot be detected or predicted using currently available hydrocarbon industry tools. Therefore this study uses extensive field studies of faults exposed at the earth's surface, to characterize these features in detail. For this study 12 fault exposures have been studied in SE Utah and the western Sinai in Egypt. The faults are mapped with mm to cm-scale detail and samples are taken for petrophysical analysis. These data are further analyzed by numerical modelling of fluid flow through the fault zones. By combining fieldwork and flow modelling, the features that most strongly affect fluid flow (key flow controls) can be identified. Key flow controls provide a tool for efficient collection of data that allow the statistical characterization of fault zones. Statistical characterization of fault zone fluid flow properties can be used to improve hydrocarbon industry workflows. This study has revealed a wide variety in fault architectures for faults in sand-shale sequences. None of the faults studied here is dominated by a single homogenous gouge of mixed sand and shale, as is assumed by many current workflows for predicting (upscaled) fault permeability. With such a wide variety of fault architectures, it is impossible to define a simple rule for the fluid-flow characteristics of faults. For successful prediction of fault sealing and fault permeability it will be necessary to successfully predict fault architecture. Predicting fault architecture will require the detailed evaluation of host rock stratigraphy, fault structureand the deformation, fluid flow and thermal history.

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Bouhouch, Lahoussine. "Élaboration des couches d'alliages NI-FE par voie électrolytique : Études électrique, magnétique et structurale." Nancy 1, 1988. http://www.theses.fr/1988NAN10089.

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Mécanismes, caractéristiques et facteurs influant le dépôt électrolytique. Techniques d'élaboration et de dosage du fer dans les alliages NI-FE déposés. Influence des conditions opératoires sur la nature et composition des alliages élaborés. Étude des propriétés électriques magnétiques et de l'influence des traitements thermiques sur la structure des alliages

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44

Perrin, Clément. "Relations entre propriétés des failles et propriétés des forts séismes." Thesis, Nice, 2014. http://www.theses.fr/2014NICE4045/document.

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J’examine les relations entre propriétés des failles géologiques long-termes et propriétés des forts séismes que produisent ces failles. J’ai compilé les données sismologiques disponibles sur les grands séismes historiques mondiaux, et cartographié, sur images satellitaires, les failles long-termes rompues par ces séismes et les traces des ruptures. L’analyse combinée des données montre que : i) les failles long-termes ont certaines propriétés génériques (organisation des réseaux, segmentation latérale, forme de distribution du glissement cumulé, etc) ; ii) les forts séismes ont également des propriétés communes (similarité de distribution du glissement cosismique, du nombre de segments rompus, de la chute de contrainte sur chaque segment majeur rompu, de la distance relative entre hypocentre et zone de glissement maximum, etc) ; iii) la maturité structurale des failles est la propriété tectonique qui impacte le plus le comportement des forts séismes. Il est probable que cette maturité diminue la friction statique et la complexité géométrique du plan de faille. Elle agit sur la localisation de la zone d’initiation du séisme, sur la localisation et l’amplitude maximum du glissement cosismique, sur la direction de décroissance de ce glissement, sur la « capacité » de la rupture à se propager et donc sur sa vitesse de propagation. Elle dicte le nombre de segments majeurs qui peuvent être rompus, et par conséquent, elle contrôle la longueur totale et la chute de contrainte globale de la rupture. Pour comprendre la physique des forts séismes, il apparaît donc indispensable d’analyser conjointement les propriétés des failles rompues et les propriétés des séismes produits
I examine the relations between the properties of long-term geological faults and the properties of the large earthquakes these faults produce. I have gathered available seismological information on large historical earthquakes worldwide and mapped in detail, on satellite images, both the long-term fault and the rupture traces. The combined analysis of the data shows that: i) long-term faults have a number of generic properties (arrangement of overall fault networks, lateral segmentation of fault traces, form of cumulative slip distribution, etc); ii) large earthquakes also have generic properties (similarity of envelope shape of coseismic slip-length profiles, of decrease in rupture width along rupture length, of number of broken segments, of stress drop on broken segments, of relative distance between hypocenter and zone of maximum slip, etc); iii) the structural maturity of the faults is the tectonic property most impacting the behavior of large earthquakes. The maturity likely acts in reducing both the static friction and the geometric complexity of the fault plane. It partly governs the location of the earthquake initiation, the location and amplitude of the maximum coseismic slip, the direction of the coseismic slip decrease, the rupture propagation efficiency and speed, the number of major fault segments that are broken, and hence the rupture length and its overall stress drop. To understand the physics of earthquakes, it thus seems necessary to analyze jointly the tectonic properties of the broken faults and the seismological properties of the earthquakes

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45

Pham, Gia Tung [Verfasser], Martin [Akademischer Betreuer] Kappas, Martin [Gutachter] Kappas, Ralph [Gutachter] Mitlöhner, Daniela [Gutachter] Sauer, Christoph [Gutachter] Dittrich, Heiko [Gutachter] Faust, and Daniel [Gutachter] Wyss. "Soil Properties Mapping and Land Evaluation for Potential Agricultural Land Use Types in A Luoi district, Thua Thien Hue province, Central Vietnam / Gia Tung Pham ; Gutachter: Martin Kappas, Ralph Mitlöhner, Daniela Sauer, Christoph Dittrich, Heiko Faust, Daniel Wyss ; Betreuer: Martin Kappas." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/118990473X/34.

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46

Pham, Gia Tung [Verfasser], Martin Akademischer Betreuer] Kappas, Martin [Gutachter] Kappas, Ralph [Gutachter] Mitlöhner, Daniela [Gutachter] Sauer, Christoph [Gutachter] [Dittrich, Heiko [Gutachter] Faust, and Daniel [Gutachter] Wyss. "Soil Properties Mapping and Land Evaluation for Potential Agricultural Land Use Types in A Luoi district, Thua Thien Hue province, Central Vietnam / Gia Tung Pham ; Gutachter: Martin Kappas, Ralph Mitlöhner, Daniela Sauer, Christoph Dittrich, Heiko Faust, Daniel Wyss ; Betreuer: Martin Kappas." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:7-21.11130/00-1735-0000-0003-C14F-B-6.

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47

Soukup, Patrik. "Diagnostika točivých elektrických strojů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377107.

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The thesis Diagnostics of rotating electric machines deals with the theory of diagnostics of rotating machines, focusing especially on the diagnosis of asynchronous motors of high power. Due to the importance of maintaining the trouble-free condition of these machines with regard to serviceability, the importance of their diagnosis is growing. Due to inappropriate working conditions or for many other reasons, different types of malfunctions may occur in the machine. The list and the way of occurrence of possible failures are included and explained in this thesis. With the growing age of the machine, it is important to check the insulation status through insulation testing. These tests are performed in the practical part of the thesis and the results are presented. In the case of asynchronous machines, each anomaly leaves a signature in the form of an electrical, magnetic or vibrational signal. These signals are analyzed and evaluated using a specific measuring equipment with the intention of deciding on the current state of the machine. Motor current signature analysis (MCSA) is considered to be the main diagnostic method of asynchronous machines in this thesis. This method is described in detail in this paper and is being applied in electrical engineering.

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48

Gonzalez, Miguel. "Nature and origin of sedimentary deposits in the Ecuador subduction trench : paleoseismological implications." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B009/document.

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La sédimentation marine récente dans les fosses de subduction est caractérisée par l'interstratification de sédiments hémipélagiques et de turbidites localement intercalées avec les coulées de débris, qui peuvent résulter de la destabilisation des pentes continentales par de tremblements de terre. La marge d’Equateur est constituée par une forte érosion tectonique qui contribue à la formation d'une fosse profonde remplie d'une suite complexe de faciès sédimentaires. La sédimentation par écoulements gravitaires est omniprésente le long de la marge et les faciès vont de dépôts de transport de masse d'épaisseur métriques latéralement continus à des turbidites d'épaisseur centimétriques isolées intercalées avec des couches d'hémipélagites, de volcanoclastiques et de téphras. Nous présentons l'interprétation de la bathymétrie, des profils sismiques à haute résolution et des données pétrophysiques des carottes sédimentaires. L'objectif de cette étude est de décrire la complexité morphologique à la frontière équatorienne de la plaque de Nazca où un ensemble d'aspérités marines profondes ont subducté à différentes échelles, et ses conséquences sur la distribution latérale des sédiments dans les différents sous-bassins. La marge équatorienne comprend trois segments géomorphologiques: Le segment nord, situé au nord de la crête Carnegie, est caractérisé par une large (5-10 km) et profonde fosse (3800-4000 m), une pente continentale ravinée et une plate-forme (10-40 km de large) avec subsidence active. Le segment central en face de la crête de Carnégie montre une fosse étroite (0-5 km de large) et peu profonde (3100-3700 m), la pente escarpée et ravinée, sans canyons, et plateau continental étroit de 15 à 40 km de large caractérisé par des zones d'affaissement et de soulèvement actifs. Enfin, le segment sud, situé au sud de la crête Carnegie, présente une large (5-10 km) et profonde fosse (4000-4700 m), une pente continentale pauvre en sédiments avec des systèmes de canyons bien définis et une large plate-forme de subsidence (20-50 km). La dynamique sédimentaire le long de la marge est évaluée par l'analyse de 15 carottes sédimentaires dont la description visuelle, les photographies à haute résolution, l'imagerie par rayons X, les données XRF et les propriétés pétrophysiques conduisent à l'identification de 11 faciès sédimentaires caractérisant 7 processus sédimentaires: dépôts de turbidite, hémipélagites, téphras, dépôts de coulées de débris, homogénites, des slumps et des dépôts de carbonate de ooze. Les âges des dépôts sont définis par la datation au radiocarbone des sédiments hémipélagites. Les âges vont de 500 à 48000 ans BP. Les profils sismiques à haute résolution permettent de définir 3 echo-faciès: transparent, stratifiés et chaotiques. Le facies transparent est principalement associé aux dépôts d'homogénites, le facies stratifié est associé aux dépôts interstratifiés turbiditique-hémipélagique et le facies chaotique est associé à des dépôts gravitaires grossiers. Le remplissage de la fosse représente un enregistrement lacunaire mais important de l'histoire de la marge de subduction. De grandes coulées de débris se déplaçant vers l'est dans les deux séquences inférieures du remplissage de la fosse sont initiées le long de la paroi extérieure de la fosse, le long de grandes failles normales dues à la flexion de la plaque océanique subductante. Les sédiments de la séquence supérieure du remplissage qui nappent la fosse sont plus largement fournis par la paroi interne de la fosse mais avec un fort contrôle de la ride de Carnegie. En conséquence, la profondeur, la fréquence, l'épaisseur, la composition et la disposition latérale des dépôts sédimentaires varient grandement entre le nord et le sud. Les grands méga-lits simples, les slumps, les coulées de débris et les homogénites sont situés dans les segments nord et sud. Ils sont déclenchés par de grands escarpements de failles régionales, dans le Nord
Recent deep marine sedimentation in subduction trenches is characterized by the inter-stratification of hemipelagic and turbidite sediments locally interbedded with debris flow, which can result from continental slope shaking triggered by earthquakes. The active margin of Ecuador comprises tectonic erosion that contributes to the formation of a deep trench filled by a complex suite of sedimentary facies. Gravity flow sedimentation is ubiquitous along the margin and facies range from laterally continuous m-thick mass transport deposits to isolated cm-thick turbidites intercalated with hemipelagite, volcanoclastics and tephra. In this study we show interpretation of swath bathymetry, high-resolution seismic profiles and petrophysical data from cores. The objective is to describe the morphologic complexity on the Ecuadorian border of the Nazca plate where a set of deep marine asperities is subducting at different scales, and their consequences on the distribution of sediments in the different sub-basins. Ecuadorian margin comprises three geomorphological segments: The northern segment, northward of the Carnegie Ridge, is characterized by a wide (5-10 km) and deep trench (3800 – 4000 m), a gentler gullied continental slope and a shelf (10-40 km wide) with active subsidence. The central segment facing the Carnegie Ridge, is strongly influenced by the subduction of the Carnegie ridge which induces a narrow (0–5 km wide) and shallow trench (3100 – 3700 m depth), a steep and gullied slope with no canyons and a 15–40 km wide shelf characterized by areas with active subsidence and uplift. Finally, the southern segment, southward of the Carnegie Ridge, presents a wide (5–10 km) and deep (4000–4700 m) trench, a starved continental slope with well-defined canyon systems and a wide subsiding shelf (20–50 km). The sedimentary dynamics along the margin is evaluated by the analysis of 15 cores. Visual description, high-resolution photographs, X-Ray imagery, XRF data and petrophysical properties led to the identification of 11 sedimentary facies that characterize seven sedimentary processes: turbidites, hemipelagites, tephras, debris flows, homogenites, slumps, and ooze carbonate deposits. Age of the deposits is defined by radiocarbon age dating of hemipelagic sediments. Ages range from 500 to 48,000 years BP. High-resolution seismic profiles allow definition of three echo-facies: transparent, layered and chaotic. Transparent echo-facies is mainly associated to homogenite deposits, layered echo-facies is associated to the turbiditic-hemipelagic interbedded deposits and chaotic echo-facies is associated to reworked gravity flow deposits. The trench fill represents a lacunar but important record of the subduction margin history. Large eastward debris flows in the lower two sequences of the trench fill are provided by the trench outer wall as a results of slope failures along normal faults due to the downward bending of the oceanic plate. The sediment of the upper sequence of the trench fill draping the trench floor, are largely provided by the inner trench wall strongly controlled by the Carnegie Ridge. As a result, depth, frequency, thickness, composition and lateral disposition of the deposits vary greatly from those at north and south. The large, simple mega-beds like slump, debris flows and homogenites are located at the northern and southern segments. They were triggered by large regional faults in the North and enhanced by the activity of sets of splay faults in the South overhanging the seafloor at the slope toe. Small-size, fluid rich events were triggered by subduction of isolated seamounts at the edges of the Carnegie Ridge due to frequent but small destabilizations of an inner trench wall preconditioned by the impacts of successive seamounts. Sets of partly volcanoclastic turbidites in central segment might have been triggered by the complex interaction of slope and continental shelf deformation by seamount subduction

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49

Gen-Je, Liou, and 劉俊杰. "Studies on Hsinchuang fault and the fault gouge properties." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/73054257912949015030.

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50

Nai-WenChang and 張乃文. "Fault-Tolerant Properties of Some Interconnection Networks." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/72224638705930844447.

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Abstract:

博士
國立成功大學
資訊工程學系碩博士班
98
With the rapid development of VLSI technology, a multiprocessor system may contain hundreds or even thousands of processors. Some of these processors may be faulty while the system is put in use. This motivates us the issues of fault-tolerant properties of multiprocessor systems. There are some popular and interesting fault-tolerant properties for multiprocessor systems such as graph embedding and system diagnosis. In this dissertation, we demonstrate our work in two aspects. The first is fault-tolerant graph embedding, and the second is fault diagnosis. Let F_v be the set of faulty nodes in a system. For fault-tolerant graph embedding, we first show that an n-dimensional M?bius cube MQ_n with at most n-1 faulty elements contains a fault-free Hamiltonian path for n＞=1, and MQ_n with at most n-2 elements is pancyclic for n＞=2. Second, we show that an n-dimensional hypercube Q_n with at most 2n-5 non-free edges and at most 2n-4 faulty elements in which each node is incident to at least two free edges contains a fault-free cycle of length at least 2^n-2|F_v|. With the previous result, we further show that under the same fault condition, Q_n contains a fault-free cycle of every even length from 4 to 2^n-2|F_v|. For fault diagnosis, we evaluate that the conditional diagnosability of an n-dimensional augmented cube AQ_n under the PMC model is 8n-27 for n＞=5.

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