The speed of the Levenberg–Marquardt ~LM! nonlinear iterative least-squares method depends upon the choice of damping strategy when the fitted parameters are highly correlated. Additive damping with small damping increments and large damping decrements permits LM to efficiently solve difficult problems, including those that otherwise cause stagnation. © 1997 American Institute of Physics. @S089...

Film damping caused by microfluids has important effects on the dynamic characteristics of moving elements of microelectromechanical system devices. There are two kinds of film damping existing in microelectromechanical system devices, for instance, slide film damping and squeeze film damping. This article presents an overview on the recent research progress on the slide film damping in microel...

Thermo-elastic damping is a significant dissipation mechanism in high quality factor microstructures. In this paper, thermo-elastic damping of the in-plane vibration of fully clamped rectangular micro-plates has been studied. The governing equation of the micro-plate motion and heat conduction equation were derived. Then, The Galerkin method has been used to solve the coupled heat-displacement ...

In this paper, we present a novel parametric model based on an important evolution of McAulay & Quatieri sinusoidal models [5]. This model takes into account a damping factor as well as a delay parameter which makes it more efficient for modeling strong audio transients such as castanets onsets without pre-echo effects. We also develop an original algorithm to estimate the model parameters by m...

In this paper we consider a multi-dimensional wave equation with dynamic boundary conditions related to the Kelvin-Voigt damping and a delay term acting on the boundary. If the weight of the delay term in the feedback is less than the weight of the term without delay or if it is greater under an assumption between the damping factor, and the difference of the two weights, we prove the global ex...

Abstract The identification of the modal parameters from frequency response functions is a subject that is not new. However, the starting point often comes from the equations that govern the dynamic motion. In this paper, a novel approach is shown, resulting from an analysis that starts on the dissipated energy per cycle of vibration. Numerical and experimental examples were used in order to as...

A generalized refined Arnoldi method based on the weighted inner product is presented for computing PageRank. The properties of the generalized refined Arnoldi method were studied. To speed up the convergence performance for computing PageRank, we propose to change the weights adaptively where the weights are calculated based on the current residual corresponding to the approximate PageRank vec...

Air-film damping, which dominates over other losses, plays a significant role in the dynamic response of many micro-fabricated devices with a movable mass suspended by various bearing mechanisms. Modeling the damping characteristics accurately will be greatly helpful to the bearing design, control, and test in various micromotor devices. This paper presents the simulated and experimental squeez...

A limitation of a simple linear mass-spring model in describing goal directed movements is that it generates rather slow movements when the parameters are kept within a realistic range. Does this imply that the control of fast movements cannot be approximated by a linear system? In servo-control theory, it has been proposed that an optimal controller should control movement velocity in addition...

The uncertainty associated with damping in structural systems is identified and discussed. A second-order perturbation technique is utilized to examine the effects of damping variability on the transient and steady-state dynamic response of structural systems. The results demonstrate that the uncertainty in damping indeed influences the system response. The effects are more pronounced for highe...