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The Evolution from Late Miocene West Salton Detachment Faulting to Cross-Cutting Pleistocene Oblique Strike-Slip Faults in the SW Salton Trough, Southern CaliforniaSteely, Alexander N. 01 May 2006 (has links)
Field studies in the southwest Salton Trough between Yaqui Ridge and Borrego Mountain show that the West Salton detachment fault was active during the Pliocene and may have initiated during the latest Miocene. At Yaqui Ridge dominantly east-directed extension is recorded by slickenlines on the NW-striking detachment fault, and shows that the fault is actually a low-angle dextral oblique strike-slip fault. Crustal inheritance is responsible for the position of the fault at Yaqui Ridge, which reactivates a late Cretaceous reverse -sense mylonite zone at map scale. Late Miocene to Pliocene basin fill deposits at Borrego Mountain display progressive unconformities, contain detritus shed from the footwall and damage zone of the West Salton detachment fault, record the growth of a large hanging wall anticline, and document the initiation and evolution of the West Salton detachment fault. The Borrego Mountain anticline is a major hanging wall growth fold that trends - N60 °W and has at least 420 m of structural relief. The late Quaternary Sunset conglomerate is - 600 m thick, lies in angular unconformity on Pliocene basin fill, is bound on the SW by the dextral oblique Sunset fault, and coarsens upward and SW toward the fault. It is dominated by plutonic lithologies from nearby areas, contains up to 10% recycled sandstone clasts from Pliocene deposits, and was shed from the SW side of the then-active Sunset fault. Based on lithologic, stratigraphic, compositional similarities, we correlate this conglomerate to part of the - 1. I - 0.6 Ma Ocotillo Formation. The West Salton detachment fault was folded and deactivated at Yaqui Ridge by the dextral oblique San Felipe fault zone starting - 1. l - 1.3 Ma. The Sunset fault is in the middle of a complex left stepover between the San Felipe fault to the NW and the Fish Creek Mountains fault to the SE. Structural analyses and mapping show that syntec tonic conglomerate, the West Salton detachment fault, and footwall crystalline rocks all have similar fold geometries and record similar amounts of NE-SW shortening. The dominant SE-trending population of slip vectors on the Sunset fault is not present on the West Salton detachment fault and suggests limited or no activation of the older detachment fault by the younger fault zone.
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Transition from compression to strike-slip tectonic styles along the northern margin of the Levant Basin / Transition de la compression au decrochement de style tectonique sur de la marge nord du bassin du LevantSymeou, Vasilis 23 February 2018 (has links)
En Méditerranée orientale, l’arc de Chypre est une frontière géologique majeure où interagissent les plaques Arabie, Afrique, Eurasie et la microplaque anatolienne. Il constitue la limite Nord du bassin du Levant (croûte continentale amincie étirée) et du bassin d’Hérodote (croûte océanique). L’arc de Chypre est directement lié à la convergence vers le Nord de la plaque Africaine sur la plaque Eurasienne depuis la fin du Crétacé. Dans la région Egéenne, l’indentation de la plaque Arabique sur la partie orientale de la plaque Anatolienne d’une part, et l’effet « roll back » du plan de subduction africain dans la partie occidentale de la plaque Anatolienne d’autre part, ont pour conséquence l’expulsion de l’Anatolie depuis la fin du Miocène à aujourd’hui, ce qui se traduit par un décrochement le long de l’arc de Chypre, se prolongeant sur l’île de Chypre. Plusieurs questions scientifiques concernant le cadre géologique de la région ont été étudiées au cours de ce projet. Comment la déformation est-elle intégrée dans le système de l'Arc de Chypre ? La variation crustale de chaque domaine affecte-t-elle le style de déformation ? Comment cette déformation est-elle enregistrée dans les sédiments de l’île de Chypre ? Comment ces déformations (Onshore / Offshore) peuvent être connectées au contexte géodynamique régional ? Afin de répondre à ces questions scientifiques, des données sismiques de réflexion 2D ont été utilisées, et ont permis d’imager les structures principales et leur évolution spatiale dans les parties Sud et Orientale de Chypre. L'interprétation de ces données conduit à l'identification de neuf unités tectono-sédimentaires dans trois différents domaines de la croûte crustale au sud du système de l'Arc chypriote: (1) le bassin du Levant (croûte continentale amincie), (2) le micro-continent d'Eratosthène (croûte continentale) et (3) le bassin d'Hérodote (croûte océanique). Dans ces domaines, de nombreuses structures tectoniques ont été documentées et analysées afin de comprendre le mécanisme et le timing de la déformation. À la limite nord du domaine du bassin du Levant, des accidents majeures chevauchants vers le Sud ont été documentés dans le bassin de Chypre, commençant au début du Miocène et enregistrés par les failles de Larnaca et de Margat. La faille Latakia n’a quant à elle enregistré aucune activité pendant cette période. L'apogée de la déformation s'est produite du Miocène moyen jusqu’à la fin du Miocene, l'activité de la faille de Latakia indiquant la propagation vers le Sud du front de déformation. Cette migration vers le sud a été documentée à partir du développement de bassins flexuraux et des chevauchements stratigraphiques dans le bassin de Chypre. Les pulses tectoniques successifs depuis la fin du Miocène jusqu’à aujourd’hui, sont indiquées par les discordances angulaires et les bassins piggy back. Pendant la période Plio-Pléistocène, l’expulsion vers l'ouest de la microplaque anatolienne a entraîné la réactivation des structures existantes. L'évolution de la déformation le long de la limite de la plaque est identifiée à partir de la création de structures en fleur positives révélant des mouvements transpressifs le long des failles Larnaca et Latakia (domaines orientaux). Le domaine central comprend le mont sous-marin d'Eratosthène qui se caractérise comme une plate-forme carbonatée mésozoïque recouverte d'une mince séquence sédimentaire allant des dépôts Messinien aux dépôts Pléistocène. / The Cyprus Arc system is major plate boundary of the Eastern Mediterranean where different plates interact, namely Arabia, Africa, Eurasia, as well as the Anatolian micro-plate. It constitutes the northern boundary of the Levant Basin (of thin stretched continental crust) and the Herodotus Basin (of oceanic crust). The Cyprus Arc is directly linked with the northward convergence of the African continental plate with respect to the Eurasian continental plate since Late Cretaceous time. The indentation of the Arabian plate and the slab pull effect of the African plate roll back in the Aegean region on the eastern and western part of the Anatolian plate respectively, leads to the westward escape of Anatolia from Late Miocene to Recent, which results in a strike-slip component along the Cyprus Arc system and onshore Cyprus. Several scientific questions with regard to the geological setting of the region were investigated during this project. How is the deformation accommodated at the Cyprus Arc system? Is this deformation style affected by the variation of the crustal nature at each domain? How is this deformation recorded on the sedimentary pile onshore Cyprus? How does the onshore and offshore deformation connect within the geodynamic context of the region? In order to answer these scientific questions, 2D reflection seismic data were utilized, that image the main plate structures and their lateral evolution south and east of Cyprus. Interpretation of these data lead to the identification of nine tectono-sedimentary packages in three different crustal domains south of the Cyprus Arc system: (1) The Levant Basin (attenuated continental crust), (2) The Eratosthenes micro-continent (continental crust) and (3) The Herodotus Basin (oceanic crust). Within these domains, numerous tectonic structures were documented and analysed in order to understand the mechanism and timing of deformation. At the northern boundary of the Levant Basin domain, thrust faults verging towards the south were documented in the Cyprus Basin with the thrust movement commencing in Early Miocene time as indicated by on the Larnaca and Margat Ridges. On the Latakia Ridge no activity was identified during this time interval. The acme of deformation occurred in Middle to Late Miocene time, with the activity of the Latakia Ridge indicating the forward propagation of the deformation front towards the south. This southward migration was documented from the development of flexural basins and from stratigraphic onlaps in the Cyprus Basin. Successive tectonic pulses through the Late Miocene until Recent times, are indicated from the angular unconformities and the piggy back basins. In Plio-Pleistocene time, the westward escape of the Anatolian micro-plate resulted in the reactivation of existing structures. The evolution of deformation along the plate boundary is identified from the creation of positive flower structures revealing transpressive movements along the Larnaca and Latakia Ridges (eastern domains). The central domain includes the Eratosthenes Seamount which is characterized as a Mesozoic carbonate platform covered by a thin sequence of sediments ranging from Miocene-Messinian to Pliocene-Pleistocene depositions.
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Modélisation des instabilités liées au frottement sec des solides élastiques, aspects théoriques et numériquesRenard, Yves 30 January 1998 (has links) (PDF)
Ce travail comporte deux parties. La première partie est une étude bibliographique sur la modélisation du frottement sec et sur les différentes lois de frottement qui ont été introduites pour rendre compte des instabilités du mouvement des solides soumis à la friction sèche. La deuxième partie est une étude théorique et numérique d'un problème modèle dynamique où une lois de type Coulomb avec coefficient de frottement dépendant de la vitesse de glissement est appliquée à un solide élastique. Le cadre des inclusions différentielles est introduit pour traiter rigoureusement les modèles à nombre fini de degré de liberté et à pression de contact imposée. Ce cadre sert ensuite à l'analyse en détail d'un problème unidimensionnel d'une couche élastique glissant avec frottement sur une fondation rigide plane. On montre l'existence et l'unicité de la solution lorsque le coefficient de frottement est croissant, mais lorsque celui-ci comporte au moins une portion décroissante, ce qui est le cas dans la plupart des modélisation, on montre que le problème admet en général une infinité de solutions. Cela amène à considerer un critère de choix de solution appelé critère de retard maximal. Par ailleurs, on introduit une condition de frottement perturbée qui consiste en l'ajout d'une masse de surface et qui redonne aussi l'unicité de la solution. On montre le lien entre le critère de retard maximal et cette condition perturbée. On présente aussi des schémas numériques, des résultats de stabilité et de convergence, ainsi que des expériences numériques. On donne enfin des perspectives pour les problèmes en dimension deux ou trois. On présente des simulations numériques significatives, obtenues à l'aide d'un schéma numérique basé sur une méthode de type directions alternées, et sur la perturbation par une masse de surface.
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Étude de l'organisation des réarrangements d'un milieu granulaire sous sollicitations mécaniquesKiesgen De Richter, Sébastien 10 November 2009 (has links) (PDF)
La réponse à des vibrations et l'étude de la stabilité des pentes ont une place particulière dans l'étude des milieux granulaires. Ces études peuvent d'une part nous renseigner sur le comportement des milieux granulaires présents dans le milieu naturel et souvent soumis à ces deux types de sollicitations (avalanches de grains, éboulements de roches, dynamique des dunes, tremblements de terre, ...). D'autre part, elles permettent d'appréhender ces milieux comme des systèmes modèles hors équilibre et d'analyser les résultats à la lumière de ceux obtenus sur la dynamique des systèmes vitreux. Nous avons tout d'abord étudié expérimentalement par des méthodes optiques et acoustiques la réponse d'un milieu granulaire lentement incliné. La dynamique présente deux régimes : un régime de petits réarrangements indépendants et localisés est suivi d'un régime intermittent caractérisé par de grands événements de type "précurseurs" au voisinage de l'angle d'avalanche. Ce régime dit de "précurseurs" correspond à un mouvement collectif de l'ensemble des grains situés à la surface de l'empilement. Nous mettons en évidence l'importance du détail microscopique de l'interaction entre les grains et de la condition à la limite à la base de l'empilement sur la dynamique du système dans ce régime. La dynamique globale du système a été étudiée et comparée à un modèle simple de type automate cellulaire. Dans un second temps, nous avons étudié numériquement la réponse d'un milieu granulaire soumis à des vibrations. Le comportement du système présente des caractéristiques qui sont communes à tous les systèmes hors équilibre (distributions non-gaussiennes des déplacements, ralentissement et hétérogénéités de la dynamique,...). L'influence de la condition à la limite au fond de l'empilement sur la structuration de celui-ci et sur le ralentissement de la dynamique a également été discutée. Nous avons, en particulier, mis en évidence une zone d'épaisseur environ égale à 5 diamètres de grains où des hétérogénéités dynamiques et de fortes corrélations entre les mouvements des grains apparaissent.
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Stability Control of Electric Vehicles with In-wheel MotorsJalali, Kiumars 14 June 2010 (has links)
Recently, mostly due to global warming concerns and high oil prices, electric vehicles have attracted a great deal of interest as an elegant solution to environmental and energy problems. In addition to the fact that electric vehicles have no tailpipe emissions and are more efficient than internal combustion engine vehicles, they represent more versatile platforms on which to apply advanced motion control techniques, since motor torque and speed can be generated and controlled quickly and precisely.
The chassis control systems developed today are distinguished by the way the individual subsystems work in order to provide vehicle stability and control. However, the optimum driving dynamics can only be achieved when the tire forces on all wheels and in all three directions can be influenced and controlled precisely. This level of control requires that the vehicle is equipped with various chassis control systems that are integrated and networked together. Drive-by-wire electric vehicles with in-wheel motors provide the ideal platform for developing the required control system in such a situation.
The focus of this thesis is to develop effective control strategies to improve driving dynamics and safety based on the philosophy of individually monitoring and controlling the tire forces on each wheel. A two-passenger electric all-wheel-drive urban vehicle (AUTO21EV) with four direct-drive in-wheel motors and an active steering system is designed and developed in this work. Based on this platform, an advanced fuzzy slip control system, a genetic fuzzy yaw moment controller, an advanced torque vectoring controller, and a genetic fuzzy active steering controller are developed, and the performance and effectiveness of each is evaluated using some standard test maneuvers. Finally, these control systems are integrated with each other by taking advantage of the strengths of each chassis control system and by distributing the required control effort between the in-wheel motors and the active steering system. The performance and effectiveness of the integrated control approach is evaluated and compared to the individual stability control systems, again based on some predefined standard test maneuvers.
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Methods for Rapid Estimation of Motor Input Power in HVAC AssessmentsChristman, Kevin D. 2010 May 1900 (has links)
In preliminary building energy assessments, it is often desired to estimate a motor's input power. Motor power estimates in this context should be rapid, safe, and noninvasive. Existing methods for motor input power estimation, such as direct measurement (wattmeter), Current Method, and Slip Method were evaluated. If installed equipment displays input power or average current, then using such readings are preferred. If installed equipment does not display input power or current, the application of wattmeters or current clamps is too time-consuming and invasive for the preliminary energy audit. In that case, if a shaft speed measurement is readily available, then the Slip Method is a satisfactory method for estimating motor input power.
An analysis of performance data for 459 motors suggests comparable performance for predicting normalized (to the nominal motor input power) motor input power with the Current and Slip Methods: 10.0% and 9.9% RMSE, respectively. Both of these methods may be improved by applying regression on the predicted variable and/or nameplate parameters. For example, the Slip Method could be improved by applying a second-order regression, thereby reducing the predicted load factor residual RMSE of the data set from 9.0% to 8.2%. The Current and Slip Methods were also evaluated on two real motors. The normalized (to the nominal motor input power) predicted input power RMSE for the Current Method was on average 15% for the two motors; for the Slip Method the corresponding average was 17.5%.
In some cases, shaft speed measurements may not be available. A temperature-based approach for estimating motor input power was investigated. Other required parameters include ambient temperature, motor efficiency, and a motor thermal constant. The temperature approach offers quick, safe, and non-invasive motor power estimation. However, thermal coefficients may vary significantly across motors and a model to predict the thermal coefficients has yet to be developed. Furthermore, the temperature approach has a very strong dependence on motor efficiency uncertainty. Experiments were performed on two motors to determine their motor thermal constants. If a motor's thermal constants and running efficiency are known, then this method gave motor input power estimates with a RMSE (normalized to the nominal input power) on the order of 4% for the studied motors.
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Numerical Investigation Of The Viscoelastic FluidsYapici, Kerim 01 July 2008 (has links) (PDF)
Most materials used in many industries such as plastic, food, pharmaceuticals, electronics, dye, etc. exhibit viscoelastic properties under their processing or flow conditions. Due to the elasticity of such materials, deformation-stress in addition to their hydrodynamic behavior differ from simple Newtonian fluids in many important respects. Rod climbing, siphoning, secondary flows are all common examples to how a viscoelastic fluid can exhibit quite distinctive flow behavior than a Newtonian fluid would do under similar flow conditions. In industrial processes involving flow of viscoelastic materials, understanding complexities associated with the viscoelasticity can lead to both design and development of hydrodynamically efficient processes and to improved quality of the final products.
In the present study, the main objective is to develop two dimensional finite volume based convergent numerical algorithm for the simulation of viscoelastic flows using nonlinear differential constitutive equations. The constitutive models adopted are Oldroyd-B, Phan-Thien Tanner (PTT) and White-Metzner models. The semi-implicit method for the pressure-linked equation (SIMPLE) and SIMPLE consistent (SIMPLEC) are used to solve the coupled continuity, momentum and constitutive equations. Extra stress terms in momentum equations are solved by decoupled strategy. The schemes to approximate the convection terms in the momentum equations adopted are first order upwind, hybrid, power-law second order central differences and finally third order quadratic upstream interpolation for convective kinematics QUICK schemes. Upwind and QUICK schemes are used in the constitutive equations for the stresses. Non-uniform collocated grid system is employed to discretize flow geometries. As test cases, three problems are considered: flow in entrance of planar channel, stick-slip and lid driven cavity flow.
Detailed investigation of the flow field is carried out in terms of velocity and stress fields. It is found that range of convergence of numerical solutions is very sensitive to the type of rheological model, Reynolds number and polymer contribution of viscosity as well as mesh refinement. Use of White-Metzner constitutive differential model gives smooth, non oscillatory solutions to much higher Weissenberg number than Oldroyd-B and PTT models. Differences between the behavior of Newtonian and viscoelastic fluids for lid-driven cavity, such as the normal stress effects and secondary eddy formations, are highlighted.
In addition to the viscoelastic flow simulations, steady incompressible Newtonian flow of lid-driven cavity flow at high Reynolds numbers is also solved by finite volume approach. Effect of the solution procedure of pressure correction equation cycles, which is called inner loop, on the solution is discussesed in detail and results are compared with the available data in literature.
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Post-paleogene Deformation In Northernmost Tip Of Tuzgolu Fault Zone (pasadag, South Of Ankara), TurkeyCeliker, Dilara Gulcin 01 December 2009 (has links) (PDF)
The research area is located to the northern tip of Tuzgolu fault zone in the junction of neotectonic structures, namely, EskiSehir-Cihanbeyli, Sungurlu-Kirikkale and Tuzgö / lü / fault zones (Central Anatolia).
The study is carried out in Paleocene sequences of PaSadag group on the structural analysis of bed, gash vein, fault and fault plane slippage data. The method of study based on i) the rose and stereo analysis of the planar structure (beds, gash veins and faults) on ROCKWORKS 2009 software and ii) on fault slip analysis on ANGELIER 1979 software.
The bed analyses done on 605 measurements manifest N10° / -20° / E bedding attitude. The analysis done on 64 gash veins shows a general trend of NNE-SSW (N15° / E). The final analysis done on 160 fault planes pointed out a general trend of NNWSSE (N20° / W).
Analysis based on the fault plane slip data manifest two stages of faulting under almost NE-SW compression during post-Paleocene &ndash / pre-Miocene period and one stage of faulting under WNW-ESE extension most probably during post-Miocene.
To conclude, the Paleocene sequences are deformed continuously under WNW-ESE directed compression which is followed by a NE-SW to N-S compression resulted in the development of a reverse to dextral strike slip faulting during post-Paleocene &ndash / pre-Miocene period.
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Frequency Domain Optimization Of Dry Friction Dampers Used For Earthquake Vibration Damping Of BuildingsErisen, Zuhtu Eren 01 March 2012 (has links) (PDF)
There are many active and passive vibration control techniques to reduce the effect of energy on structures which emerges during an earthquake and reduce the displacement of buildings that is caused by ground acceleration. Main advantage of passive vibration control techniques over active vibration control techniques is / no external power or a sensor is required for passive vibration control devices (PVCDs) and it results in lower installation and maintenance costs. However, PVCDs require a predefined optimum damping ratio and optimum damping distribution along the structure since they are not adaptive to changing ground acceleration values. During the design of the PVCDs numerous factors such as building properties and earthquake characteristics should be considered. Dry friction damper is an example of PVCD and has an extensive usage in many different fields due to its high energy damping capacity with low cost and ease of installation. In this thesis, damping of seismic energy at buildings with dry friction dampers is investigated and a new optimization method is developed in frequency domain by employing Describing Function Method (DFM) which reduces the computational effort compared to the time domain and finite element solutions drastically. The accuracy and verification of the presented method is investigated by comparing the frequency domain results with time marching solutions. Furthermore, damper placement and slip forces on the dampers are optimized for single and multi-story buildings equipped with dry friction dampers by utilizing the developed method.
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Antispinn för högprestandabilar och motorsportWesterlund, Niklas January 2006 (has links)
<p>This master’s degree project includes the construction, implementation and the theory of function of the traction control system NTRAC, a traction control system designed to increase performance. A closer functionality study of the more common safety-designed traction control systems has been executed. As a result of this study different techniques in decreasing engine torque has been concluded. NTRAC uses a fuel-cutting method to decrease the torque. The risks and consequences by this, as well as different solutions, are in detail discussed in the report.</p><p>One of the main design purposes with NTRAC was to be able to adapt it easily to different vehicles. To evaluate this ability NTRAC has been implemented into two test vehicles, most different to each other by means of physical measurements. As an outcome of this evaluation, a number of mathematical models have been derived and implemented in numerical MATLAB programs. Two models are explained in the report and are included in MATLABfiles as appendix three and four at the end of the report.</p><p>The first model describes the dependency between the action of decrease in torque and the relative remaining degree of efficiency and the report explains why this does not show a linear dependency. The friction between the tire and the road surface plays a crucial part in the theory behind traction control and the report describes in detail how traditional traction control systems are designed to make compromises, in wheel spin tolerances, and thus not uses the maximum amount of traction. To increase performance traction control systems continuously have to optimise this amount and also minimise its fluctuations. Wheels travel with different speeds when cornering, thus the traction control system has to compensate for this, and the second mathematical model in the report describes this in detail.</p><p>Finally an increase in performance is verified through the usage of NTRAC in the formula car KTHR2. During an international competition in the summer of 05, at Bounthingsthorp proving grounds, Leicestershire, England, under perfect weather conditions, a time-saving of nine percentage where registered at acceleration tests from 0 to 75 meters. </p>
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