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We analysed the ground deformation across two blocks defined by the Rio-Patras fault from 1993 to 2017 using multi-temporal Synthetic Aperture Radar Interferometry (InSAR) techniques. Our main objective was to contribute to the assessment of seismic hazard near the large city of Patras. Multiple data-sets were used, each one covering different temporal periods. Descending and ascending acquisitions, providing different viewing geometries contribute to fully determine the ground displacement in 3D. The data-sets used are from the European Space Agency’s (ESA) European Remote Sensing (ERS), Environmental Satellite (ENVISAT) and SENTINEL-1 as well as German Aerospace Center (DLR) ’s TERRASAR-X missions. Considering ESA’s missions covering both acquisition geometries and long periods, the southern block, showing lack of a sufficient number of scatterers does not allow the displacement characterization. In contrary, the northern block is characterized by a high number of scatterers having values of maximum likehood ranging from ?3.5 to ?4.3 mm year?1 for ascending geometry and from ?1.6 to ?2.7 mm year?1 for the descending one. The fact that both geometries show negative values of displacements are consistent with downlift movement and at the same time the quantitative differentiation probably indicates an horizontal component as well.  相似文献   
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This work concerns the micromechanical constitutive modelling, algorithmic implementation and numerical simulation of polycrystalline superelastic alloys under multiaxial loading. The model is formulated in finite deformations and incorporates the effect of texture. The numerical implementation is based on the constrained minimization of the Helmholtz free energy with dissipation. Simulations are conducted for thin tubes of Nitinol under tension–torsion, as well as for a simplified model of a biomedical stent. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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Contents The control-canonical-form (CCF) method is introduced for the purpose of applying it to high-order state-space single-input single or multiple-output (SISO or SIMO) and multiple-input multiple-output (MIMO) linear time-invariant system models to determine closed-loop systems (i.e. design robust controllers) from which enchanced dynamic stability characteristics and overall performance of these systems is achieved. The method has been applied successfully to a SISO 6th-order linearized state-space open-loop model (representing a simplified hydro power system), and to a MIMO 8th-order linearized state-space open-loop model (representing an 87.5 kVA synchronous machine with conventional exciter supplying power to an electric utility system through an interconnection network)
Anwendung der kanonischen Form der Zustandsrückführung auf Erzeugersysteme zur Verbesserung der dynamischen Stabilitätseigenschaften
Übersicht Die Methode der kanonischen Form wird auf lineare zeitinvariante Systeme höherer Ordnung im Zustandsraum angewendet, die eine oder mehrere Eingangsgrößen bei einer oder mehreren Ausgangsgrößen aufweisen. Damit werden robuste Regler entworfen, welche die dynamische Stabilität und das gesamte Betriebsverhalten verbessern. Die Methode wurde erfolgreich auf ein linearisiertes Modell sechster Ordnung mit einem Eingang und einem Ausgang angewendet, das vereinfachend eine Wasserkraftanlage darstellt; außerdem auf ein linearisiertes Zustandsmodell achter Ordnung einer Synchronmaschine 87,5kVA mit konventioneller Erregung, die über ein Verbindungsnetzwerk in das öffentliche Netz einspeist.
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Improving Awareness in Mobile CSCW   总被引:1,自引:0,他引:1  
The diffusion of mobile devices in the working landscape is promoting collaboration across time and space. Following through this development, we investigate opportunities for improving awareness in mobile environments with a view to enable collaboration under power constraints and transitory network disconnections. We elaborate in particular on synchronous CSCW and expose with it significant details of group awareness, while we contribute a protocol for awareness support over large areas that strikes a balance between energy consumption and notification time. To avoid user disruption, this protocol notifies awareness information in a multicast fashion, while the bandwidth is allocated dynamically among notifications and data requests, thus minimizing the time needed by each one of them and ensuring the isochronous delivery of information to all clients. The efficiency and scalability of our protocol are evaluated with simulation experiments, whereby we compare various notification schemes and finally choose one that changes dynamically over time.  相似文献   
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Monocarboxylate transporters (MCTs) are of great research interest for their role in cancer cell metabolism and their potential ability to transport pharmacologically relevant compounds across the membrane. Each member of the MCT family could potentially provide novel therapeutic approaches to various diseases. The major differences among MCTs are related to each of their specific metabolic roles, their relative substrate and inhibitor affinities, the regulation of their expression, their intracellular localization, and their tissue distribution. MCT4 is the main mediator for the efflux of L-lactate produced in the cell. Thus, MCT4 maintains the glycolytic phenotype of the cancer cell by supplying the molecular resources for tumor cell proliferation and promotes the acidification of the extracellular microenvironment from the co-transport of protons. A promising therapeutic strategy in anti-cancer drug design is the selective inhibition of MCT4 for the glycolytic suppression of solid tumors. A small number of studies indicate molecules for dual inhibition of MCT1 and MCT4; however, no selective inhibitor with high-affinity for MCT4 has been identified. In this study, we attempt to approach the structural characteristics of MCT4 through an in silico pipeline for molecular modelling and pharmacophore elucidation towards the identification of specific inhibitors as a novel anti-cancer strategy.  相似文献   
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