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Late Pleistocene displacement along the Lone Mountain fault suggests the Silver Peak-Lone Mountain (SPLM) extensional complex is an important structure in accommodating and transferring strain within the eastern California shear zone (ECSZ) and Walker Lane. Using geologic and geomorphic mapping, differential global positioning system surveys, and terrestrial cosmogenic nuclide (TCN) geochronology, we determined rates of extension across the Lone Mountain fault in western Nevada. The Lone Mountain fault is the northeastern component of the SPLM extensional complex, and is characterized by a series of down-to-the-northwest normal faults that offset the northwestern Lone Mountain and Weepah Hills piedmonts. We mapped eight distinct alluvial fan deposits and dated three of the surfaces using ¹⁰BE TCN geochronology, yielding ages of 16.5 +/- 1.2 ka, 92.3 +/- 8.6 ka, and 142.2 +/- 19.5 ka for the Q3b, Q2c, and Q2b deposits, respectively. The ages were combined with scarp profile measurements across the displaced fans to obtain minimum rates of extension; the Q2b and Q2c surfaces yield an extension rate between 0.1 +/- 0.1 and 0.2 +/- 01 mm/yr and the Q3b surface yields a rate of 0.2 +/-.1 to 0.4 +/- 0.1 mm/yr, depending on the dip of the fault. Active extension on the Lone Mountain fault suggests that it helps partition strain off of the major strike-slip faults in the northern ECSZ and transfers deformation around the Mina Deflection northward into the Walker Lane. Combining our results with estimates from other faults accommodating dextral shear in the northern ECSZ reveals an apparent discrepancy between short- and long-term rates of strain accumulation and release. If strain rates have remained constant since the late Pleistocene, this could reflect transient strain accumulation, similar to the Mojave segment of the ECSZ. However, our data also suggest an increase in strain rates between ~92 ka and ~17 ka, and possibly to present day, which may also help explain the mismatch between long- and short-term rates of deformation in the region.

<p>För att ett fordon ska kunna bromsa, accelerera och svänga är friktion mellan däcken och vägen ett måste. Vid för mycket gaspådrag under en acceleration kan det hända att hjulen förlorar fäste och börjar spinna loss, något som leder till både försämrad kontroll över fordonet och att däcken slits ut i förtid. Traction controlsystemet förhindrar hjulen från att spinna loss och försöker maximera friktionen.</p><p>Målet med detta examensarbete är att utvärdera olika reglerprinciper samt att undersöka olika möjligheter för att reglera friktionen mellan däck och väg. Det är ett svårt reglerproblem, dels på grund av dess olinjäritet, dels på grund av det faktum att friktionen är en okänd parameter.</p><p>För att kunna undersöka olika reglermöjligheter har en modell över hjuldynamiken och en modell över drivlinan tagits fram i Matlabs simuleringsprogram Simulink. Därutöver har tre regulatorer designats: en fuzzy-regulator, en fuzzy-P-regulator och en PI-regulator. Regulatorerna utvärderades i tre tester som bland annat testade deras robusthet.</p><p>Fuzzy-regulatorn och fuzzy-P-regulatorn lyckades reglera systemet bra. PI-regulatorn gjorde däremot inte ett tillfredsställande jobb, mest på grund av dess behov av ett börvärde.</p> / <p>Traction is necessary for a vehicle to be able to brake, accelerate and turn. When pushing the accelerator pedal too hard during an acceleration, the wheel can loose traction and start spinning, which leads to a worsen vehicle control and also wears out the tyres faster. The traction control system prevents the wheels from spinning and tries to make the tyres maintain maximum traction.</p><p>The purpose of this master’s thesis is to evaluate different control methods and to investigate possible ways to control the traction. This is a difficult control problem due to its nonlinearity and the fact that the friction is an unknown parameter.</p><p>For the investigation, a model of the wheel dynamics and a model of the powertrain have been developed in Matlab’s simulation program Simulink. Furthermore, three different controllers have been designed; a fuzzy controller, a fuzzy-P controller and a PI controller. The controllers were evaluated in three test cycles that among others tested their robustness.</p><p>The fuzzy controller and the fuzzy-P controller managed to control the system very well. The PI controller, however, did not work satisfactory, mainly because of its need of a desired value.</p>

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vi, 21, [24] p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 20-21).

A study f the characters of the Tertiary dyke-swarms of Skye, Ardnmurchan and. the Small Isles of Invernessshire is based on observations at over 7500 dyke-outcrops, most of whiciL are located along well-exposed traverses. Because of geological limitations analyses of the properties of the dykes (trend, dip and thickness) can be semi-statistical only. Each of the dyke-swarms consists of a regional linear component of LW. to N.N.W. trending dykes, including parallel secondary-swarms in Skye and Ardnamurchan, together with in Skye and R.hum N.E. subswarnis of distinctive geo-. graphic distribution and comparatively- low intensities. The observations taken have facilitated: (a.) the construction of contour-maps depicting symmetrical distributions of multiple- dykes, of the arithmetic-average trends and thicknesses of the dykes, etc., (b.) both an approximate delimitation of regional-swarms and the distinction of these from subsidiary-avarms, in each case on the basis of the intensity- distribution and trend-distribution of the constituent dykes, and Cc.) the discovery of a latent plutonic -complex near Jluck, az a possible "centre" off the rwrth-west coast of Lewis. The trends, thicknesses, and to some extent the dips of small groups of dykes are intimately related to: (i.) the locations of those dykes with respect to the axes of highintensity of both crustal-stretch (dilation) and number of dykes per kilometre, (ii.) the positions of the dykes in relation to the site of the roughly contemporaneous Central Intrusive Coiiplexes, and (iii.) the structure of the country-- rock in which the dykes were emplaced, especially in the cases of the !oinian rocks, the Tertiary lavas, and the peripherally folded Mesozoic rocks bordering the Central Complex of Skye. The form and structure of the dyke-swarms, the distribution of the petrological types of dykes, and the available aeromagnetic, gravity-anomaly, and radiometric-dating evidence, indicate that the emplacement of each dyke-swarm is related to a sone of N.W. transcurrent faulting roughly paralleling the major dilation-axis of the swarm. Such faults were the consequence of differential movement of crustal blocks away from the line of a proposed Tertiary separation (Rockall Trough) of the British mainland and Rockall Plateau. Intracrustal, elongate, ridge-like basaltic magma-reservirs, whose ultimate source was the upper mantle, are believed to have ascended each of these faults. At the intersections of the N.W. transcurrent faults with preexisting N.E. faults cylinders of basaltic magma arose to form the Central Intrusive Complexes. Dyke-swarms developed as offshoots of the basaltic ridges and to a small extent from the basaltic cylinders, under the influence of a N.E. to S.W. tension resulting from a relative separation in this same direction of' the crustal blocks on both sides of the Rockall Trough rift.

Downhole vibrations lead to downhole failures and decrease the rate of penetration (ROP). The bottom hole assembly (BHA) static and dynamic design is a key factor in optimizing drilling operations. The BHA should be designed to minimize the vibration levels in the axial, lateral, and torsional directions. This would be achieved by avoiding rotating the drillstring in the speeds that are nearby the natural frequency of BHA. The complexity associated with current BHA components requires using advanced computational tools that are capable of solving complex and time-consuming equations. Finite Element Analysis (FEA) is the most used technique in analyzing vibration behavior of the drillstring by mesh discretizing of a continuous body into small elements. This thesis will study the dynamic behavior of different BHA designs for Manifa and Karan fields of Saudi Aramco to optimize the drilling operations. The FEA software that will be used to conduct these studies is called Vibrascope™, which was developed by NOV. The software will determine the critical speeds of the drillstring that should be avoided to prevent resonance of the BHA, which will lead to severe downhole vibration. / text

The three largest earthquakes in the last 25 years in southern California occurred on faults located adjacent to the southern San Andreas fault, with the M7.3 1992 Landers and M7.1 1999 Hector Mine earthquakes occurring in the eastern California shear zone (ECSZ) in the Mojave Desert, and the M7.2 2010 El Mayor-Cucapah earthquake occurring along the Laguna Salada fault in northern Baja California, Mexico. The locations of these events near to but not along the southern San Andreas fault (SSAF) is unusual in that the last major event on the SSAF occurred more than 300 years ago, with an estimated recurrence interval of 215± 25 years. The focus of this dissertation is to address the present-day deformation field along the North America-Pacific plate boundary in southern California and northern Baja California, through the analysis of GPS data, and elastic block and viscoelastic earthquake models to determine fault slip rates and rheological properties of the lithosphere in the plate boundary zone. We accomplish this in three separate studies. The first study looks at how strain is partitioned northwards along-strike from the southern San Andreas fault near the Salton Sea. We find that estimates for slip-rates on the southern San Andreas decrease from ~23 mm/yr in the south to ~8 mm/yr as the fault passes through San Gorgonio Pass to the northwest, while ~13-18 mm/yr of slip is partitioned onto NW-SE trending faults of the ECSZ where the Landers and Hector Mine earthquakes occurred. This speaks directly to San Andreas earthquake hazards, as a reduction in the slip rate would require greater time between events to build up enough slip deficit in order to generate a large magnitude earthquake. The second study focuses on inferring the rheological structure beneath the Salton Trough region. This is accomplished through analysis of postseismic deformation observed using a set of the GPS data collected before and after the 2010 El Mayor-Cucapah earthquake. By determining the slip-rates on each of the major crustal faults prior to the earthquake, we are able to model the pre-earthquake velocity field for comparison with velocities measured using sites constructed post-earthquake. We then determine how individual site velocities have changed in the 3 years following the earthquake, with implications for the rate at which the lower crust and upper mantle viscously relax through time. We find that the viscosity of the lower crust is at least an order of magnitude higher than that of the uppermost mantle, and hypothesize that this is due to mafic material emplaced at the base of the crust as the spreading center developed beneath the Salton Trough since about 6 Ma. The final study investigates crustal deformation and fault slip rates for faults in the northern Mojave and southern Walker Lane regions of the ECSZ. Previous geodetic studies estimated slip-rates roughly double those inferred via geological dating methods in this region for NW striking strike-slip faults, but significantly smaller than geologic estimates for the Garlock fault. Through construction of a detailed elastic block model, which selects only active fault structures, and applying a new, dense GPS velocity field in this region, we are able to estimate slip-rates for the strike-slip faults in the ECSZ that are much closer to those reported from geology.

För att ett fordon ska kunna bromsa, accelerera och svänga är friktion mellan däcken och vägen ett måste. Vid för mycket gaspådrag under en acceleration kan det hända att hjulen förlorar fäste och börjar spinna loss, något som leder till både försämrad kontroll över fordonet och att däcken slits ut i förtid. Traction controlsystemet förhindrar hjulen från att spinna loss och försöker maximera friktionen. Målet med detta examensarbete är att utvärdera olika reglerprinciper samt att undersöka olika möjligheter för att reglera friktionen mellan däck och väg. Det är ett svårt reglerproblem, dels på grund av dess olinjäritet, dels på grund av det faktum att friktionen är en okänd parameter. För att kunna undersöka olika reglermöjligheter har en modell över hjuldynamiken och en modell över drivlinan tagits fram i Matlabs simuleringsprogram Simulink. Därutöver har tre regulatorer designats: en fuzzy-regulator, en fuzzy-P-regulator och en PI-regulator. Regulatorerna utvärderades i tre tester som bland annat testade deras robusthet. Fuzzy-regulatorn och fuzzy-P-regulatorn lyckades reglera systemet bra. PI-regulatorn gjorde däremot inte ett tillfredsställande jobb, mest på grund av dess behov av ett börvärde. / Traction is necessary for a vehicle to be able to brake, accelerate and turn. When pushing the accelerator pedal too hard during an acceleration, the wheel can loose traction and start spinning, which leads to a worsen vehicle control and also wears out the tyres faster. The traction control system prevents the wheels from spinning and tries to make the tyres maintain maximum traction. The purpose of this master’s thesis is to evaluate different control methods and to investigate possible ways to control the traction. This is a difficult control problem due to its nonlinearity and the fact that the friction is an unknown parameter. For the investigation, a model of the wheel dynamics and a model of the powertrain have been developed in Matlab’s simulation program Simulink. Furthermore, three different controllers have been designed; a fuzzy controller, a fuzzy-P controller and a PI controller. The controllers were evaluated in three test cycles that among others tested their robustness. The fuzzy controller and the fuzzy-P controller managed to control the system very well. The PI controller, however, did not work satisfactory, mainly because of its need of a desired value.

‘What was I thinking ?!?’ – No matter age, intelligence or social status, we all experience moments like these. Perhaps it is walking into a room and forgetting what you went there to do or maybe failing to add sugar to your coffee due to an interruption. Regardless, even though many of our daily activities are accomplished through routines that require very little conscious effort, errors of attention or slips of action do occur. This collection of studies was designed with three main questions in mind: 1) can action slips be induced in a laboratory-based task (Slip Induction Task; SIT), 2) how well do currently established theories of action slips explain the errors that are induced within the SIT, and 3) what insight can be gained about preventing such errors? The first experiment was developed to replicate previous findings regarding the effectiveness of the SIT, as well as to determine the extent to which SIT performance correlates with other measures of attention failure. The study discussed in Chapter 3 expands on those results by investigating the effects of healthy aging on slip induction and finds that while older adults were better able to avoid action slips, they appear to sacrifice speed for accurate performance. The goal of the subsequent study was to determine whether young adult participants would also enjoy increased accuracy if they completed the task at a slower pace. Finally, the study discussed in Chapter 5 looks at whether changing the goal of the SIT would alter participants’ ability to inhibit unexpected cue information.

Zircaloy-2 is used extensively in the nuclear industry as a structural material for the reactor core in both light and heavy water reactors. The intergranular strains and texture greatly affect the mechanical properties of the material while in operation. Understanding the plastic deformation of Zircaloy-2 will improve on current plastic deformation models, particularly for twinning mechanisms, which are more active at lower temperatures, and are not yet well understood. For this study, neutron diffraction was used to track the lattice spacing and peak intensity in warm-rolled and recrystallized Zircaloy-2 slab for various crystallographic orientations at 77 K. Tests were performed in all three principle directions under tension and compression. The texture was measured for the deformed samples to help interpret the dominant deformation systems and then Electron Back Scattering Diffraction was used to identify and image the active twinning modes. Prism <a> slip, basal <a> slip, {10-12} and {11-2 1} tensile twinning, and {11-2 2} compression twinning were found to be contributing deformation systems in Zircaloy-2 at 77K. In this study, the diffraction elastic constants for Zircaloy-2 at room temperature and 77K are reported for the first time in open literature. These values will be useful in future experimental work by allowing a conversion between lattice spacing and residual stress. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-09-24 13:41:25.371