Search results for "STRAIN"

Linking Economic Stress to Marital Quality Among Finnish Marital Couples

1998

Structural equation modeling was used to test the mediators of economic circumstances on marital quality using a sample of married or cohabiting 36-year-old Finnish men ( n = 133) and women ( n = 117). The model tested was an adapted version of the model presented by Conger, Ge, and Lorenz. For the men, the results were consistent with the proposed model: Poor employment status caused economic strain and affected the lives of the men to the extent that current economic strain increased expected financial strain, leading to greater depression and greater hostility in the marriage, both of which, in turn, predicted poor marital quality. For the women, poor economic circumstances and, in part…

Corrigendum: Wired for motherhood: induction of maternal care but not maternal aggression in virgin female CD1 mice

2021

Domain knowledge integration and semantical quality management -A biology case study

2008

International audience; The management of semantical quality is a major challenge in the context of knowledge integration. In this paper, we describe a new approach to constraint management that emphasizes constraint traceability when moving from the semantical level to the operational one.Our strategy for management of semantical quality is related to a metamo-deling-based approach to knowledge integration. We carry out knowledge integration “on the fly” by using transformations applied to models belonging to our metamodeling architecture. The resulting integrated models access available resources through web services whose input and output parameters are guarded by constraints. Integrated…

Development of antitaxial fringes during non-coaxial deformation: an experimental study

2003

Strain fringes were modelled experimentally around wooden objects in a simple-shear box containing Polydimethylsiloxane (PDMS). The fringes were made of paraffin wax that was periodically poured into dilated sites next to the core-object and left to crystallise. In the experiments fringes and core-object rotated at similar decreasing rotation rates relative to extensional incremental stretching axes (ISA) of flow and rotated relative to each other by small amounts. Fringes did not necessarily open parallel to ISA due to interactions between fringes and core-object. Therefore, neither displacement-controlled fibres nor object-centre paths can be expected to record the exact orientation of th…

Shakedown analysis for a class of strengthening materials within the framework of gradient plasticity

2010

Abstract The classical shakedown theory is extended to a class of perfectly plastic materials with strengthening effects (Hall–Petch effects). To this aim, a strain gradient plasticity model previously advanced by Polizzotto (2010) is used, whereby a featuring strengthening law provides the strengthening stress, i.e. the increase of the yield strength produced by plastic deformation, as a degree-zero homogeneous second-order differential form in the accumulated plastic strain with associated higher order boundary conditions. The extended static (Melan) and kinematic (Koiter) shakedown theorems are proved together with the related lower bound and upper bound theorems. The shakedown limit loa…

View Planning Approach for Automatic 3D Digitization of Unknown Objects

2012

International audience; This paper addresses the view planning problem for the digitization of 3D objects without prior knowledge on their shape and presents a novel surface approach for the Next Best View (NBV) computation. The proposed method uses the concept of Mass Vector Chains (MVC) to define the global orientation of the scanned part. All of the viewpoints satisfying an orientation constraint are clustered using the Mean Shift technique to construct a first set of candidates for the NBV. Then, a weight is assigned to each mode according to the elementary orientations of its different descriptors. The NBV is chosen among the modes with the highest weights and which comply with the rob…

Optical flow estimation from multichannel spherical image decomposition

2011

The problem of optical flow estimation is largely discussed in computer vision domain for perspective images. It was also proven that, in terms of optical flow analysis from these images, we have difficulty distinguishing between some motion fields obtained with little camera motion. The omnidirectional cameras provided images with large filed of view. These images contain global information about motion and allow to remove the ambiguity present in perspective case. Nevertheless, these images contain significant radial distortions that is necessary to take into account when treating these images to estimate the motion. In this paper, we shall describe new way to compute efficient optical fl…

RECRUITMENT OF BICEPS FEMORIS MUSCLE REGIONS AT DIFFERENT RUNNING SPEEDS

2017

Background The majority of hamstring strain injuries (HSIs) occur in the late swing phase of high-speed running when hamstrings work eccentrically. The proximal region of the biceps femoris (BF) seems to be the most common site of injury. Elongation of the fascicles in eccentric contractions is higher in the proximal region compared to the distal region of BF, but the neural background to this phenomenon is not clear. Objective To examine the region-specificity of BF muscle activity at different running speeds. Design Observational study. Running speeds were randomized. Setting Laboratory, amateur level. Participants Football players without acute injury/illness, and without HSI history wer…

Optimal die Design for Cold Extrusion Processes

1999

The design of cold extrusion processes requires the optimisation of several process variables in order to obtain a defect free product. The fulfilment of different objectives, such as the minimisation of forming loads or the homogeneity of the deformations, is highly requested. Nevertheless, several other relevant aspects of extrusion processes have to be taken into account and require a suitable optimisation of the process parameters and in particular of the die shape. In this paper, tool life has been assumed as the most relevant goal and an effective die design procedure as been setup. It is well known that fatigue cracking of the dies is the principal cause of dies failure in cold extru…

Using a neural network for qualitative and quantitative predictions of weld integrity in solid bonding dominated processes

2014

Solid-state bonding occurs in several manufacturing processes, as Friction Stir Welding, Porthole Die Extrusion and Roll Bonding. Proper conditions of pressure, temperature, strain and strain rate are needed in order to get effective bonding in the final component. In the paper, a neural network is set up, trained and used to predict the bonding occurrence starting from the results of specific numerical models developed for each process. The Plata-Piwnik criterion was used in order to define a quantitative parameter taking into account the effectiveness of the bonding. Excellent predictive capability of the network is obtained for each process.