Search results for "Displacement"
showing 10 items of 433 documents
Evaluation of different InSAR multi-baseline construction methods over a dam in southern Italy
2018
Monitoring dam displacements using different techniques allows an evaluation of their structural behaviour over time. In this study, dam displacements (for the Castello dam, Agrigento, Italy) have been investigated using different Interferometric Synthetic Aperture Radar (InSAR) techniques exploiting a freely available dataset from the EU Copernicus Sentinel-1 SAR built by the European Space Agency (ESA). The dataset includes Sentinel 1A (S1A) images acquired in dual-polarization and Interferometric Wide (IW) swath using the Terrain Observation with Progressive Scans SAR (TOPSAR) mode. Three main Multi-Baseline Construction methods based on the identification of Persistent Scatterers (PS) h…
Bounding principles for elastic-plastic-creeping solids loaded below and above the shakedown limit
1982
Solids of elastic-perfectly plastic creeping material subjected to variable loads are considered within the infinitesimal displacement framework and a bounding principle is presented which holds below and above the shakedown limit. Through the choice of some free parameters, this principle generates a number of deformation bounds with practical meanings, some of wich coincide with known results for creeping and noncreeping material, while others constitute new results or generalizations of known results. The topic will be further studied in a subsequent paper [35].
Comparative analysis of numerical and experimental data of orthodontic mini-implants
2011
The purpose of this study was to compare numerical simulation data derived from finite element analysis (FEA) to experimental data on mini-implant loading. Nine finite element (FE) models of mini-implants and surrounding bone were derived from corresponding experimental specimens. The animal bone in the experiment consisted of bovine rib. The experimental groups were based on implant type, length, diameter, and angle of insertion. One experimental specimen was randomly selected from each group and was digitized in a microCT scanner. The FE models consisted of bone pieces containing Aarhus mini-implants with dimensions 1.5 × 7 mm and 1.5 × 9 mm or LOMAS mini-implants (dimensions 1.5 × 7 mm, …
Removal of a migrated dental implant from a maxillary sinus through an intraoral approach: A case report
2021
Background The replacement of maxillary posterior teeth often challenges the clinician due to bone resorption after dental exodontia and low bone quality. Currently, attempts are being made to shorten treatment times by placing implants simultaneously to sinus lift procedures in borderline cases, which can lead to complications such as displacement of implants into the maxillary sinus. Clinical case A 54-year-old patient who was planned for complete rehabilitation of the maxilla through a fixed implant-supported prosthesis on 6 implants. At the level of the 3rd sextant, a sinus lift was performed with a lateral window approach (Caldwell-Luc type) and the simultaneous placement of two implan…
Deportation, Crisis, and Social Change
2018
In contemporary migration policy and practice across the globe, deportation has emerged as an apparently inevitable response to real, or otherwise perceived, migration crises. A skeptical attitudetoward the analytic use of “crisis” in the context of deportation is called for, as is the need to concentrate on the political genealogy of the term, which culminates in the justification of “emergency” policies and the implementation of new measures of control. Yet, at the same time—when states govern undocumented or unwanted residents through deportation and employ the notion of crisis for justifying irregular and often violent acts towards deportable subjects—a situation emerges that indeed sha…
Later-life depressive symptoms and anxiety attacks in displaced and nondisplaced populations
2021
Abstract Background Forced displacement has been suggested as a potential cause for depression and anxiety in later life. Little research has been done on the influence of the host country's socio-political system. Here we examine whether the later-life effects of displacement on mental health (i.e. depressive symptoms and anxiety attacks) differ between socio-political contexts. We hypothesized that between-group differences (displaced vs. nondisplaced) in self-rated depression scores and frequencies of anxiety attacks are more pronounced in East versus West German populations. Methods Datasets from three representative nationwide surveys (2002, 2003, 2007) were analyzed; study participant…
Speckle Interferometry Analysis of Full-bending Behavior of GFRP Pultruded Material
2016
Abstract The use of Glass Fiber Reinforced Polymer materials (GFRP) has increased in the last years even among civil structural engineering due to their high specific strength, lightweight and excellent corrosion resistance. With application of the pultrusion method, the manufacture of large-scale profiles with various cross-section forms became potentially possible with relatively low costs. Usually two different technological approaches are available to realize the element: in the first one a mat-roving-mat sequence is adopted, in the second one only roving is present. Continuous filament mat (CFM, fibers distributed randomly in all directions) is often used to build up laminate thickness…
3D displacement field measurement with correlation based on the micro-geometrical surface texture
2011
Image correlation methods are widely used in experimental mechanics to obtain displacement field measurements. Currently, these methods are applied using digital images of the initial and deformed surfaces sprayed with black or white paint. Speckle patterns are then captured and the correlation is performed with a high degree of accuracy to an order of 0.01 pixels. In 3D, however, stereo-correlation leads to a lower degree of accuracy. Correlation techniques are based on the search for a sub-image (or pattern) displacement field. The work presented in this paper introduces a new correlation-based approach for 3D displacement field measurement that uses an additional 3D laser scanner and a C…
Proper 1-ball contractive retractions in Banach spaces of measurable functions
2005
In this paper we consider the Wosko problem of evaluating, in an infinite-dimensional Banach space X, the infimum of all k > 1 for which there exists a k-ball contractive retraction of the unit ball onto its boundary. We prove that in some classical Banach spaces the best possible value 1 is attained. Moreover we give estimates of the lower H-measure of noncompactness of the retractions we construct. 1. Introduction Let X be an infinite-dimensional Banach space with unit closed ball B(X) and unit sphere S(X). It is well known that, in this setting, there is a retraction of B(X) onto S(X), that is, a continuous mapping R : B(X) ! S(X) with Rx = x for all x 2 S(X). In (4) Benyamini and Sternf…
A meshfree method for transverse vibrations of anisotropic plates
2003
A meshfree approach, called displacement boundary method, for anisotropic Kirchhoff plate dynamic analysis is presented. This method is deduced from a variational principle, which uses a modified hybrid functional involving the generalized displacements and generalized tractions on the boundary and the lateral deflection in the domain as independent variables. The discretization process is based on the employment of the fundamental solutions of the static problem operator for the expression of the variables involved in the functional. The stiffness and mass matrices obtained for the dynamic model are frequency-independent, symmetric and positive definite and their computation involves bound…