A displacement-velocity feedback control method is proposed to enhance the isolation performance of a quasi-zero-stiffness vibration isolator (QZS-VI). Time delay considered in controlled QZS-VI system. First, steady-state solutions are obtained using averaging and validated by numerical method. The jump phenomenon frequency island can occur, stability analysis implemented. Then, effects time g...

A desirable characteristic for nonlinear vibration isolators is a high static stiffness and a low dynamic stiffness. A curved beam is a possible candidate for this role provided that the amplitude of vibration about the static equilibrium position is sufficiently small. However, for large amplitude oscillations, the nonlinear dynamics may have a detrimental effect. This paper considers the forc...

Tomato spotted wilt virus (TSWV) is transmitted exclusively by thrips in nature. A reassortment-based viral genetic system was used to map transmissibility by thrips to the medium (M) RNA of TSWV. To locate determinants of thrips transmission in the M RNA, 30 single-lesion isolates (SLIs) were generated from a single TSWV isolate that was inefficiently transmitted by thrips. Three of the 30 SLI...

The relationship between corneal edema and hydrogel lens oxygen transmissibility was examined for both daily and extended contact lens wear by measuring the corneal swelling response induced by a variety of contact lenses over a 36-hr wearing period. The relationships derived enable average edema levels that occur with daily and extended wear in a population of normal young adults to be predict...

BACKGROUND Whole body vibration has recently been used as a therapeutic intervention for the treatment of children with disabling conditions. Researchers of these studies observed encouraging results; however, children may not be capable of attenuating high vibration accelerations to the head because of low mass. The purpose of this study was to determine if children transmit vibration differen...

Evidence suggests that wheelchair (WC) users are exposed to unhealthy levels of vibration during WC use. Health risks associated with vibration exposure include vertebral disc degeneration and back pain, which may consequently decrease the function and independence of WC users. Some evidence suggests that the cushions used in WCs may amplify vibrations, although conclusive evidence has not been...

21 There is a lack of a common concept on how to estimate transmissibility of 22 Chlamydia trachomatis from cross-sectional sexual partnership studies. Using a 23 mathematical model that takes into account the dynamics of chlamydia transmis24 sion and sexual partnership formation, we report refined estimates of chlamydia 25 transmissibility in heterosexual partnerships. 26