In this paper we consider an inverse problem for a damped vibration system from the noisy measured eigendata, where the mass, damping, and stiffness matrices are all symmetric positive definite matrices with the mass matrix being diagonal and the damping and stiffness matrices tridiagonal. To take into consideration the noise in the data, the problem is formulated as a convex optimization probl...

An innovative structural modification, top-story softening, is herein proposed in conjunction with an optimally tuned top-floor mass damper inerter (TMDI) for improved serviceability performance typical core-frame slender buildings rectangular floor plan susceptible to wind-induced vortex shedding (VS) effects causing occupant discomfort. This supported through formulating a novel optimal TMDI ...

objective(s): the aim of this study was to synthesize triangular gold nanoparticles, and then to evaluate their capability for inhibition of candida albicans secreted aspartyl proteinase 2(sap2).materials and methods: to synthesize the nanoparticles, hydrogen tetrachloroaurate and hexadecyl trimethyl ammonium bromide were incubated in presence of sn(iv) meso-tetra(n-methyl-4-pyridyl) porphine t...

This paper presents the development of a magnetorheological (MR) fluid-based variable stiffness and damping isolator for vibration suppressions. The MR fluid isolator used a sole MR control unit to achieve the variable stiffness and damping in stepless and relative large scope. A mathematical model of the isolator was derived, and a prototype of the MR fluid isolator was fabricated and its dyna...

Chronic hypoxic pulmonary hypertension (HPH) is associated with large pulmonary artery (PA) stiffening, which is correlated with collagen accumulation. However, the mechanisms by which collagen contributes to PA stiffening remain largely unexplored. Moreover, HPH may alter mechanical properties other than stiffness, such as pulse damping capacity, which also affects ventricular workload but is ...

Distractions affect postural control, but this mechanism is not well understood. Diversion of resources during cognitive stress may lead to decreased motor drive and postural muscle tone. This may appear as decreased postural stiffness and increased postural sway amplitude. We hypothesized that dual tasking leads to decreased stiffness and increased sway amplitude. Postural sway (center of pres...

the present article seek to investigate the function of elliptical steel damper function in steel frames seismic resisting. the elliptical damper is a kind of earthquake energy dissipater in structure which acts based on the steel yielding feature. thus, this damper in frame lateral displacement mechanism is expected to have a satisfying hysteretic behavior in terms of energy absorption is on a...

As the vibration of high speed train becomes fierce when the train runs at high speed, it is crucial to develop a novel suspension system to negotiate train’s vibration. This paper presents a novel suspension based on Magnetorheological fluid (MRF) damper and MRF based smart air spring. The MRF damper is used to generate variable damping while the smart air spring is used to generate field-depe...

In this paper, we present the concept of adapting to changes in ground conditions like stiffness, damping and friction, using a novel two degree of freedom reconfigurable leg length hopping robot with a fixed passive compliance. In such a robot, the change in the dynamics of the single legged hopper can be induced by the change in coupled stiffness and damping of the system, i.e., stiffness and...