Shot peening has been developed to enhance the fatigue strength of metallic parts. However, improper shot peening can decrease the fatigue life due to induced high surface roughness and residual tensile stress. The effectiveness of the manual shot peening process is accomplished by the control of the process parameters to provide a uniform intensity and coverage throughout the work piece. This ...

A new model for fatigue damage evolution of polymer matrix composites is presented. The model is based on a combination of an orthotropic damage model and an isotropic fatigue evolution model. The orthotropic damage model is used to predict the orthotropic damage evolution within a single cycle. The isotropic fatigue model is used to predict the magnitude of fatigue damage accumulated as a func...

In this paper, influence of riveting process parameters, namely, riveting force, sheet thickness, friction coefficient and clearance fit are investigated on residual stress field and fatigue life of single riveted lap joint of AA2024 type. According to the effect of riveting induced residual stresses on fatigue life of riveted lap joint, these parameters are optimized to maximize the residual s...

A polycyclic fatigue damage model for short glass fibre reinforced thermoplastics is developed and implemented into ABAQUS FE code using UMAT subroutine. The MNL model is introduced here in terms of damage rates: ( ) ) ( 2 0 1 2 0 2 1 2 1 1 ) ( ) ( N ij ij ij ij ij ij ij ij ij ij ij e E E N d d λ β ε γ ε β β α − −       +       + = ∂ ∂ = & (1) Where N is the number of cycles. αij, β...

In this work various methods and algorithms for face and eyes detection are examined in order to decide which of them are applicable for use in a driver fatigue monitoring system. In the case of face detection the standard Viola-Jones face detector has shown best results, while the method of finding the eye centers by means of gradients has proven to be most appropriate in the case of eyes dete...

BACKGROUND Lecithin is a complex mixture of phospholipids which compose lipid bilayer cell membranes. Lipid replacement therapy, or administration of phospholipids for the purpose of repairing the dmaged cell membranes, had been shown to alleviate fatigue. The present study aimed to investigate the effect of soy lecithin on fatigue in middle-aged women, as well as other menopausal symptoms and ...

This study examines how lower extremity fatigue of the quadriceps alters gait variables related to slip propensity. Sixteen healthy young adults were recruited to walk across vinyl floor surfaces in states of fatigue and no fatigue. Kinematic and kinetic data were collected using a three-dimensional motion analysis system and force plates. The results indicated a significant increase in both th...