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THE DISPLACEMENT rate is given for a mode III crack growing in a steady state under dynamic conditions. The material is assumed to be visco-plastic and high strain rates are considered. A regular perturbation expansion is performed. First-order perturbing strains are, with one exception, square root singular near the crack-tip. For overstress exponents less, or equal to 2, a reasonably large regioTHE DISPLACEMENT rate is given for a mode III crack growing in a steady state under dynamic conditions. The material is assumed to be visco-plastic and high strain rates are considered. A regular perturbation expansion is performed. First-order perturbing strains are, with one exception. square root singular near the crack-tip. For overstress exponents less. or equal to 2, a reasonably large regio

Active surveillance (AS) is broadly described as a management option for men with low-risk prostate cancer, but semantic heterogeneity exists in both the literature and in guidelines. To address this issue, a panel of leading prostate cancer specialists in the field of AS participated in a consensus-forming project using a modified Delphi method to reach international consensus on definitions of t

The fracture process of a laminate is analysed. The laminate is a material used for packaging.It consists of a thin aluminium foil with a polymer coating. In both materials, the fractureprocesses are supposed to be dominantly localized plastic deformation. A Barenblatt regionis supposed to spread ahead of the crack tip. This region is analysed in its cross planeinvoking plane deformation conditionThe conditions for crack arrest at speeds down to below 0.1 of the Rayleigh-wave speed are examined. The elastic energy release rate is assumed to be balanced by the deformation work in a viscoplastic continua and the energy release rate in a fracture process region. Fractographic show that a small fraction of the surface is created through ductile rupture. Even though the fraction represents only

Absence epilepsy (AE) is classified as a genetic generalized epilepsies. WAG/Rij strain of rats are regarded one of the most validated models of absence epilepsy. Studies point out the existence of hyperexcitable focus in somatosensory cortex of these rats, which has been attributed to the deficits in the GABAergic system. In the current study, we studied the changes of calcium binding proteins (C

An investigation of the autonomy of the process region at the tip of a crack is carried out. An elastic plastic linearly hardening material is assumed. A cohesive zone model with constant cohesive stress is chosen. The cohesive zone length is observed to decrease with decreasing hardening rates and increasing cohesive stresses. For a cohesive stress larger than about three times the yield stress tAn investigation of the autonomy of the process region at the tip of a crack is carried out. An elastic plastic linearly hardening material is assumed. A cohesive zone model with constant cohesive stress is chosen. The cohesive zone length is observed to decrease with decreasing hardening rates and increasing cohesive stresses. For a cohesive stress larger than about three times the yield stress t

Under åren 2014-2018 röjdes över 200 fågelskär inom Natura2000-områden i Vänern. Röjningarna genomfördes inom projektet LIFE Vänern. Syftet med röjningarna var att förhindra igenväxning av skär som är attraktiva häckningsplatser för fåglar i Vänern. Denna rapport utvärderar korttidsutvecklingen av antalet häckande fåglar på de röjda skären i jämförelse med skär som ej röjdes inom LIFE-projektet oc

The elastic singular fields for a crack perpendicular to and with its tip at the interface between two isotropic elastic solids with different elastic moduli are given. The asymptotic crack tip fields for are obtained cases where either both materials yield perfectly plastically or one material remains elastic. By using the singular elastic field as a prescribed load, small scale yielding solutionThe elastic singular fields for a crack perpendicular to and with its tip at the interface between two isotropic elastic solids with different elastic moduli are given. The asymptotic crack tip fields for are obtained cases where either both materials yield perfectly plastically or one material remains elastic. By using the singular elastic field as a prescribed load, small scale yielding solution

The current status of crack tip characterizations is reviewed. Several unresolved areas for further research are identified. Singular fields for stationary and moving crack tips in different non-linear materials are reviewed and special emphasis is put on the extension of the region where these fields dominate. The use of path-area integrals, asymptotically elastic crack tips, and crack initiation

At self-similarity the strain history is implicit in and deducible from the strain field at each instance of the loading process. This fact is taken advantage of in a FEM-technique which allows the load to be applied in one single step, only, even when the incremental theory of plastic flow has to be used. Two self-similar problems are solved. Firstly an analytically solvable anti-plane strain craAt self-similarity the strain history is implicit in and deducible from the strain field at each instance of the loading process. This fact is taken advantage of in a FEM-technique which allows the load to be applied in one single step, only, even when the incremental theory of plastic flow has to be used.Two self-similar problems are solved. Firstly an analytically solvable anti-plane strain crac

Elastic—plastic anti‐plane strain problems can be solved by using FEM programs developed for plane stress. The technique does not involve any manipulations with the FEM code, but is merely a matter of specialization and of translation of notation. Two analytically solvable cases are chosen for demonstration.

Crude Distillation Unit (CDU) represents significant challenge for retrofitting and energy optimisation as the most energy intensive consumer in a conventional crude oil refinery. Pinch Technology and its based-methodologies are found primary keys for decades to energy savings in refining industries for a range of common economic-based and environmental objectives or applications. Typical benefits

Linnénätet är tänkt att uppmärksamma historiskt intressanta växtlokaler och fokuserar på lokaler som varit kända sedan före 1850. Även om många av dem ingår i Floraväkteriet, så har det sig att flera av dessa inte är skyddade och några har inte ens varit uppmärksammade. Jan Thomas Johansson och Mariette Manktelow har startat detta projekt om historiska växtlokaler i Sverige, och här följer en pres

Background: The influence of gender on bipolar disorder is controversial and it is unclear if inpatient care differs between men and women. Here, we investigate for gender differences in the inpatient length of stay for Swedes admitted for bipolar disorder and explore other factors that could explain any observed association. Methods: Admission data were extracted from the Swedish National Patient