We introduce a stress/total-pressure formulation for poroelasticity that includes the coupling with steady nonlinear diffusion modified by stress. The problem is written in mixed-primal form, perturbed twofold saddle-point system an elliptic problem. continuous analysed framework of abstract fixed-point theory and Fredholm alternative compact operators. A mixed finite element method proposed it...

The best known isotropic membrane stress state is a soap film. However, if we allow the value of the isotropic stress to vary from point to point then the surface can carry gravity loads, either as a hanging form in tension, or as a masonry shell in compression. The paper describes the theory of isotropic membrane stress under gravity load and introduces a particle method for its numerical simu...

Zirconia-nickel functionally graded materials were obtained by powder metallurgy technique. The microstructure, residual stress, fracture toughness and Vickers hardness were investigated. Mixed-mode fracture response of YSZ /Ni functionally graded materials was examined utilizing the three point bending test and finite element method (Cosmos/M 2.7). The results show that the stress intensity fac...

Modifying stress-strain curves is one of the important topics in mechanical engineering and materials science. Real stress-strain curves should be modified after necking point as stress becomes three-dimensional after creation of throat, and consequently, equivalent stress should be used instead of axial one. Also, distribution of triple stresses across throat section is not uniform anymore, an...

This article has studied the effect of ratio of stiffness and thickness between piezoelectric actuators and host plat has been explored on optimal pattern for placement of piezoelectric work pieces around a hole in thin isotropic plate under static loading to reduce stress concentration. The piezoelectric actuators reduce directly or indirectly the stress concentration by applying positive and ...

BACKGROUND Submariners are an occupational group within the Royal Navy (RN) who work in isolated and extreme conditions. This preliminary study forms part of a longitudinal study of occupational stress in the RN. AIMS To compare stress prevalence in submariners with matched controls and to identify predictors of occupational stress in submariners over a 2 year follow-up period. METHODS Part...

Pathways of mutagenesis are induced in microbes under adverse conditions controlled by stress responses. Control of mutagenesis by stress responses may accelerate evolution specifically when cells are maladapted to their environments, i.e. are stressed. Stress-induced mutagenesis in the Escherichia coli Lac assay occurs either by 'point' mutation or gene amplification. Point mutagenesis is asso...