A method for analysis of essentially nonlinear vibrations of cyclically symmetric structure has been developed. Two major cases are analysed: (i) steady-state periodic multiharmonic vibrations; (ii) transient vibrations. The method allows exact calculation of the essentially nonlinear vibrations to be performed using a model for only one period of the cyclic symmetry. A rigorously proof of poss...

During courtship, individuals transfer information about identity, mating status and quality. However, male web-building spiders face a significant problem: how to begin courting female spiders without being mistaken for prey? Male Argiope spiders generate distinctive courtship vibrations (shudders) when entering a female's web. We tested whether courtship shudders delay female predatory behavi...

one of the great challenges in the processing of materials using equal channel angular pressing (ecap) is the high forming forces required to produce large shear deformation in the material. researchers show that the friction forces between the die and the sample constitute a great part of the total forming forces. recently, ultrasonic vibrations are successfully implemented into the ecap proce...

in this paper deflection and free vibration of sandwich panel is studied. the core of sandwich panels is made of hexagonal honeycomb and faces are made of two different materials of carbon fiber reinforced plastic and k-aryl/epoxy covering. the governing equations are deduced from the first order sheer deformation theory (fsdt) and they are solved using generalized differential quadrature metho...

Most Westem opera singers report feeling phonatory vibrations, i.e., vibrations caused by phonation, in different parts of their bodies while singing. As one perceives one's own voice quite differently from one's listeners, it has been hypothesized that phonatory vibrations may be useful as a feedback signal for the control of phonation. These vibrations have been examined in some articles whic...

In this paper the quantitative influence of external vibrations on the measurement value of a Coriolis Mass-Flow Meter for low flows is investigated, with the eventual goal to reduce the influence of vibrations. Model results are compared with experimental results to improve the knowledge on how external vibrations affect the measurement error. A Coriolis Mass-Flow Meter (CMFM) is an active dev...

I examined the role of vibrations in predator-induced early hatching of red-eyed treefrogs, Agalychnis callidryas. The arboreal eggs of A. callidryas hatch up to 30% early if attacked by egg-eating snakes. This induced hatching is a behavioural response that occurs once snakes begin physically disturbing the clutch, and is sufficiently rapid to allow most embryos to escape. Other intense but be...

To investigate the contribution of topographically organized brain areas to tactile working memory, we asked human subjects to compare the frequency of two vibrations presented to the same fingertip or to different fingertips. The vibrations ranged from 14 to 24 Hz and were separated by a retention interval of variable length. For intervals <1 sec, subjects were accurate when both vibrations we...