The study of fundamental structural dynamic properties is critical for improving Micro-electromechanical System (MEMS) design and functionality. A new facility for measuring the structural dynamics of microsystem parts with a base-excitation technique is described and experimental results from a study of the effect of gas damping on the structural dynamics of MEMS are presented. The new facilit...

To describe a metastable electric dipole state in a biological system, Fröhlich suggested a nonlinear model potential. In this paper we investigate a system of two nonlinear dipoles, which are coupled by a dipole-dipole interaction. We apply an external field and add linear damping terms. The external drive leads to a phase-locking of the dipoles. Mathematically, the system corresponds to an ex...

Damping treatments are used in most Naval platforms to reduce noise and vibration, and are therefore critical to structural acoustic performance. However, the complexity of naval structures often limits one's ability to accurately estimate the structural acoustic performance of a given damping treatment. As a result, some damping treatments represent a significant cost without a significant ben...

A combination of stiffness and loss (the product Etan ) is desirable in damping layer and structural damping applications. Composite materials of structure which gives rise to Reuss or Hashin–Shtrikman lower bound behavior can give rise to such properties. Hierarchical particulate morphologies attain the Hashin– Shtrikman curve. We show that hierarchical composites give rise to complex Poisson’...

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...

0020-7683/$ see front matter 2013 Elsevier Ltd. A http://dx.doi.org/10.1016/j.ijsolstr.2013.03.018 ⇑ Corresponding authors. Tel.: +1 608 346 7275 (L. Don E-mail addresses: [email protected] (L. (R. Lakes). High structural damping combined with high stiffness is achieved by negative stiffness elements. Negative incremental structural stiffness occurs when a column with flat ends is subjecte...

We study stochastic resonance (SR) in an oscillator with nonlinear noise, fractional-order external damping, and fractional-order intrinsic damping. Using a moment equation, we derive the exact analytical expression of the output amplitude and find that fluctuations in the output amplitude are non-monotonic. Using numerical simulations we verify the accuracy of this analytical result. We find (...

Linear Landau damping and nonlinear wave-particle trapping oscillations are observed with standing plasma waves in a trapped pure electron plasma. For low wave amplitudes, the measured linear damping rate agrees quantitatively with linear Landau damping theory. At larger amplitudes, the wave initially damps at the Landau rate, then regrows and oscillates, approaching a steady state, as predicte...