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Two groups of pigeons were trained with a go/no-go proeedure to diseriminate video Images of eonspecifies based on the individuals or else on their aetions. Both groups showed rapid aequisition, and the diserimination transferred to new seenes in Experiment 1 and to static seenes in Experiment 2, In Experiment 3, experimentally naive pigeons were trained to diseriminate video Images of particular birds showing different aetions. Transfer to novel seenes, including a new bird and a new motion, revealed the dominanee of motion as a eue to diseriminate video Images, In Experiment 4, the pigeons trained to diseriminate video seenes of 2 pigeons showing a variety of activities sueeessfully reeognized these stimuli regardless of whether the video was played forward or baekward, and transferred the diserimination to still seenes. The findings suggest that pigeons' diserimination ofvideo images is primarily based on information that is invariant aeross statie and dynamic eonditions.Individual recognition is of great ecological relevance to animals. It is important for animals to respond differentially and appropriately to their social partners and to other individuals. There is little or no doubt that the ability to recognize individuals is based on perceptual and cognitive factors and on species-typical social interactive behaviors. Still or moving pictures of conspecifics have been used to study cognition and social behaviors in apes

The effects of fine particle peening on the fatigue properties of transformation-induced plasticity (TRIP)-aided bainitic ferrite steel were investigated for applications to precision gears. Fine particle peening increased the fatigue limit and lowered the notch-sensitivity in the TRIP-aided bainitic ferrite (TBF) steel, compared with SNCM420 steel. In the stress intensity range of less than 25 MPa m 1/2 , TBF steel subjected to fine particle peening exhibited a larger threshold value of the stress intensity range and higher crack propagation rate than SNCM420 steel. The increased fatigue properties are principally associated with (1) higher Vickers hardness, (2) higher compressive residual stress and (3) plastic relaxation resulting from the strain-induced transformation of metastable retained austenite in a surface hardening layer, which may suppress fatigue crack initiation and propagation.

To apply a transformation-induced plasticity (TRIP)-aided steel consisting of bainitic ferrite structure matrix and metastable retained austenite of 10 vol% (TBF steel) to some precision gears, the effects of fine particle peening on the Vickers hardness and residual stress in a surface layer of the TBF steel were investigated. The peened surface layer showed much higher Vickers hardness and compressive residual stress than those of a quenched and tempered SNCM420 steel. The increased Vickers hardness was mainly caused by an increase in the strain-induced transformed martensite fraction. The compressive residual stress was increased by the increases in size and gravity of shot material and arc-height. The higher compressive residual stress was principally associated with (1) plastic strain due to severe plastic deformation and (2) expansion strain due to the strain-induced transformation of metastable retained austenite. Contribution of the (2) was approximately 30% of total residual stress.

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