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Η πόλη της Πάτρας βρίσκεται σε μία περιοχή του Ελληνικού χώρου, που χαρακτηρίζεται από πρόσφατες τεκτονικές δομές. Το πλήθος και το μέγεθος των ρηγμάτων που απαντούν στην ευρύτερη περιοχή, μαρτυρούν μια έντονη νεοτεκτονική δραστηριότητα που συνεχίζεται μέχρι σήμερα με την εκδήλωση σεισμικότητας. Οι ρηξιγενείς ζώνες και εξ’ ορισμού οι σεισμικές πηγές, έχουν επιπτώσεις στην τρωτότητα πυκνοκατοικημένων περιοχών, τόσο στην περιοχή της Πάτρας, όσο και στην ευρύτερη περιοχή. Το σύνολο των ρηγμάτων αυτών έχει αντίκτυπο στις κατασκευές προκαλώντας προβλήματα στην καθημερινότητα των πολιτών όταν διέρχονται από τον αστικό ιστό μιας πόλης. Τρία ενεργά ρήγματα εντοπίσθηκαν να επηρεάζουν τον αστικό ιστό της Πάτρας. Από Βορρά προς Νότο αυτά είναι το ρήγμα στη περιοχή της εστίας του Πανεπιστημίου Πατρών, το ρήγμα της οδού «Πέντε Πηγαδίων» στη περιοχή της Αγίας Σοφίας και το ρήγμα της Αγίας Τριάδας. Ο εντοπισμός των ρηγμάτων έχει γίνει με τον συνδυασμό διαφόρων πληροφοριών από παλαιότερες μελέτες και σημερινά στοιχεία. Περιγράφεται και αναλύεται η μορφολογία και τα χαρακτηριστικά τους ως προς τις μακροσεισμικές παρατηρήσεις γύρω τους, όπως τις επιφανειακές διαρρήξεις οι οποίες προκαλούν ζημιές στις κατασκευές καθώς και τα επίπεδα θορύβου του εδάφους, ενώ επιχειρείται συσχετισμός μεταξύ τους. Για την εργασία χρησιμοποιήθηκαν το «Impulse laser» για την αποτύπωση της μορφολογίας και η τεχνική HVSR για τη μέτρηση του εδαφικού θορύβου. / The city of Patras is an area of the Greek space, characterized by recent tectonic structures. The number and size of faults occurring in the region, indicate an intense neotectonic activity that continues until today with the event seismicity. The fault zones and default seismic sources, affect the vulnerability of densely populated areas, in the region of Patras, and in the wider region. The total of these faults in construction causing problems in the daily life of citizens when crossing the urban fabric of a city. Three active faults identified to affect the urban fabric of Patras. From north to south these are the fault of the University of Patras, the fault of the road "Five Wells" in the area of St. Sophia and the fault in the area of the Ag.Triadas. The detection of these are done by combining various information from past research and current information. Described and analyzed the morphology and their characteristics in terms of macroseismic observations around them, such as surface faulting which cause damage to structures and the ground noise and attempted correlation between them. Was used the «Impulse laser» for the description of morphology and technical HVSR to measure the ground noise.

This study is based on a regional grid of seismic data acquired by Merlin Geophysical. The main emphasis of this thesis was on the detailed structural mapping of the Danish Central Graben, since this area has the highest density of well and seismic data. The principal objective of the study was to explain why the North Sea Rift changes strike in the Danish Sector, from the N-S trending Dutch Central Graben, to the NW-SE trending U.K/Norwegian Central Graben. The Danish Central Graben opened initially in the Late Carboniferous, as part of a regional dextral transtensile deformation that affected much of Europe. The initial extensional structures developed by reactivation of a pre-existing basement fabric. The NNW trending Coffee Soil Fault bounding the rift, is interpreted as a planar structure transecting the entire crust, and is thought to have developed by extensional reactivation of an east-verging Caledonian thrust. Basement shear zones identified on the rift shoulders on the Ringkobing-Fyn High are interpreted as the along-strike continuation of the Caledonides of Southern Norway, offset to the east by syn-orogenic transform motion along fracture zone elements of the Tornquist Zone. The WNW trending fault zones that dominate the structural grain in the Danish Central Graben are shown to be closely related to WNW trending fracture zones on the Ringkobing-Fyn High, which are regarded as splay shears of the Tornquist Zone. The WNW trending transverse fault zones segment the Danish Central Graben. The segmentation exerted a fundamental influence on the structural and stratigraphic development of the rift, in that individual segments were free to subside at different rates, in different styles, at different times. Two main phases of rifting are recognised, Permo-Triassic, and Middle and Upper Jurassic. These two phases have contrasting patterns of subsidence, and contrasting structural expression, particularly as regards the extent of the involvement of the transverse fault zones. The Permo-Triassic phase is characterised by parallelism of stratal configurations, and horizontal subsidence of the graben floor, whereas the Jurassic phase is characterised by strongly divergent configurations and asymmetric, rotational subsidence directed towards and controlled by the Coffee Soil Fault. Active rifting ceased at the end of the Jurassic, and Lower Cretaceous sediments are found to onlap extant fault scarps in a passive infill of the rift basin. The major bounding structures of the rift change strike abruptly in several incremental steps across the points of intersection with the transverse segment boundaries. The re-orientation of the rift is therefore explained as a consequence of the underlying presence of the earlier transform dominated basement fabric. A model for the formation of the North Sea Rift is proposed, which draws heavily on observations of the fracture patterns in continental rifts such as the Oslo Rift and the Rio Grande Rift, and is a development of the Megashear-Rhombochasm concept of S.W.Carey.

It is preferable that control and bearing condition monitoring are integrated, as the condition of the system should influence control actions. As wind turbines mainly work in remote areas, it becomes necessary to develop a wireless platform for the control system. A fuzzy system with self-tuning mechanism was developed. The input speed error and speed change were selected to control the shaft speed, while the kurtosis and peak-to-peak values were used as another set of inputs to monitor the bearing conditions. To enhance effectiveness, wait-and-see (WAS) logic was used as the pre-processing step for the raw vibration signal. The system was implemented on the LabVIEW platform. Experiments have shown that the system can effectively adjust motor rotating speed in response to bearing conditions. For future studies, more advanced fault detection methods can be integrated with proper tuning mechanisms to enrich the performance and function of the controller.

This thesis aims to investigate the stresses at mid-ocean ridge offsets, and particularly at the particular class of offsets represented by oceanic microplates. Amongthese, the Easter microplate is one of the best surveyed. This thesis first studies the stress field associated with mid-ocean ridges and simple types of ridge offsets, and then uses the stress field observed at Easter to constrain the driving mechanism of microplates. Two-dimensional finite element modelling is used to predict the lithospheric stress indicators, which are then compared with observations. Extensional structures at high angles (> 35 ) to ridge trends are often observed at ridge-transform intersections and non-tranform offsets, but remained unexplained until now. This study proposes that the topographic loading created by the elevation of mid-ocean ridges relative to old seafloor is a source of ridge parallel tensile stresses, and shows they can be explained by the rotation of ridge parallel tensile stresses at locked offsets. The elasto-plastic rheology is used to investigate the evolution of normal faults near mid-ocean ridges. It is shown that variations in the lithospheric strength, caused entirely by variations in the brittle layer thickness, can account for the observed variations in fault character with spreading rate and along-axis position. Plasticity is shown to prevent the achievement of large fault throws in thin brittle layers. Consequently, it may be important at fast spreading ridges. A new dynamic model is proposed for Easter microplate. It mainly consists of: 1) driving forces along the East and West Rifts, resulting from the combination of a regional tensile stress with an increasing ridge strength towards rift tips, 2) mantle basal drag resisting the microplate rotation, and contributing with less than 20% to the total resisting torque, and 3) resisting forces along the northern and southern boundaries. To explain both the earthquake focal mechanism evidence and theexistence of compressional ridges in the Nazca plate, the boundary conditions alongthe northern boundary are required to change with time, from completely locked tolocked in the normal direction only. This study does not invalidate the microplate kinematic model proposed by Schouten et al. (1993), but shows that normal resisting forces along the northern and southern boundaries of Easter microplate must exist in order to explain the stress observations. Also, it suggests that ridge strength variations play an important role in the dyamics of mid-ocean ridge overlap regions.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "August, 2007." Includes bibliographical references (leaves 116-126). Online version available on the World Wide Web.

Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 4, 2008) Includes bibliographical references.

Thesis (Ph.D.) -- University of Adelaide, National Centre for Petroleum Geology and Geophysics, 2000. / Four folded maps in pocket on back cover. Copy of author's previously published work inserted. Includes bibliographical references (9 leaves).

Thesis (M.S.)--University of Montana, 2008. / Title from title screen. Description based on contents viewed Aug. 20, 2008. Includes bibliographical references (p. 43-49).

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 106 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 100-103).