In sheet metal forming processes with complex strain paths, a part is subjected to large plastic deformation. This severe plastic deformation leads to high plastic strain localization zones and subsequent accumulation of those strains. Then internal and superficial micro-defects and in other words ductile damage is created. This damage causes quality problems such as fracture. Therefore, design...

The deep stable layer of compressive residual stress produced by low plasticity burnishing (LPB) has been demonstrated in laboratory testing to improve damage tolerance in engine alloys IN718, Ti-6Al-4V, Ti-6-2-4-6, and 17-4PH. This paper describes the fatigue and FOD tolerance benefits afforded by LPB treatment of a Ti-6Al-4V first stage fan blade and vane. FOD sensitive blades and vanes remov...

The tolerance of plants to herbivory reflects the degree to which a plant can regrow and reproduce after damage from herbivores. Autoecological factors, as well as the influence of competitors and mutualists, affect the level of plant tolerance. Recent work indicates that there is a heritable basis for tolerance and that it can evolve in natural plant populations. Although tolerance is probably...

Plants can resist herbivore damage through three broad mechanisms: antixenosis, antibiosis and tolerance(1). Antixenosis is the degree to which the plant is avoided when the herbivore is able to select other plants(2). Antibiosis is the degree to which the plant affects the fitness of the herbivore feeding on it(1).Tolerance is the degree to which the plant can withstand or repair damage caused...

1. Herbivore damage can select for tolerance in plant populations where genetic variation for tolerance exists. The causes underlying variation in tolerance are not fully resolved. We assessed the importance of two potential mechanisms for tolerance by examining its relationship with leaf photosynthetic rate and relative biomass allocation across plant organs. 2. We monitored responses of 12 as...

Tolerance to parasites reduces the harm that infection causes the host (virulence). Here we investigate the evolution of parasites in response to host tolerance. We show that parasites may evolve either higher or lower within-host growth rates depending on the nature of the tolerance mechanism. If tolerance reduces virulence by a constant factor, the parasite is always selected to increase its ...

an energy based damage index based on a new nonlinear finite element (fe) approach applicable to rc structures subjected to cyclic, earthquake or monotonic loading is proposed. the proposed method is based on the evaluation of nonlinear local degradation of materials and taking into account of the pseudo-plastic hinge produced in the critical sections of the structure. a computer program is dev...

Ultraviolet radiation (UVR) is a ubiquitous environmental factor and with complex diverse effects on organisms, the UVR tolerance of species varies due to selection, adaptation evolution. This study aimed improve our understanding interspecific differences in fishes. First, we compared skin histology between high-altitude fishes their low-altitude relatives. Second, assessed histological change...

Field and greenhouse experiments showed that yield losses of sugarbeet, Beta vulgaris, did not occur in soil infested with fewer than eight Heterodera schachtii eggs/g soil. However, larger population densities greatly reduced sugarbeet yield. In the field experiment, the yield in microplots inoculated with more than 64 eggs/g soil was less than 20% of yields in uninoculated microplots. Neverth...