Received (Day Month Year) Revised (Day Month Year) In this paper, we study the behaviour of a MEMS oscillator by applying methods of nonlin-ear dynamics. We model the system as a kicked damped oscillator and obtain the iterative maps that describe the MEMS system. The dynamics of the maps are studied numerically: we present a study of limit cycles and their rotation numbers and show how the con...

Numerically studies have shown that the bi-stability and backward bifurcation are not automatically connected in epidemic models. In fact, when a backward bifurcation occurs, the disease-free equilibrium may be globally stable or it may support to a stable limit cycle. In this paper, a continuous epidemic model that incorporates density-dependent treatments is analyzed. It is shown that it supp...

This work concerns superharmonic perturbations of a Gaussian measure given by a special class of positive weights in the complex plane of the form w(z) = exp(−|z| + U(z)), where U(z) is the logarithmic potential of a compactly supported positive measure μ. The equilibrium measure of the corresponding weighted energy problem is shown to be supported on subharmonic generalized quadrature domains ...

The Homophone Meaning Generation Test (HMGT; Warrington, 2000) is a new measure of verbal fluency that has been demonstrated to be sensitive to the presence of anterior lesions. In the present study we used the HMGT healthy standardization sample (N = 170) and demonstrate that scores on the HMGT do not differ significantly from a normal distribution and that the test has adequate reliability (a...

The chapter addresses bifurcations of limit cycles for a general class of nonlinear control systems depending on parameters. A set of simple approximate analytical conditions characterizing all generic limit cycle bifurcations is determined via a first order harmonic balance analysis in a suitable frequency band. Moreover, due to the existing connection between limit cycle bifurcations and rout...

A general parametrically and externally excited mechanical system is considered. The main attention is focused on the dynamical properties of local bifurcations as well as global bifurcations including homoclinic and heteroclinic bifurcations. In particular, degenerate bifurcations of codimension 3 are studied in detail. The original mechanical system is first transformed to averaged equations ...

In this paper we study the existence, number and distribution of limit cycles of the perturbed Hamiltonian system: 0960-0 doi:10 E-m x0 1⁄4 4yðabx by þ 1Þ þ ex ux þ vy b þ 1 l þ 1 x y ux k y0 1⁄4 4xðax aby 1Þ þ eyðux þ vy þ bxy vy kÞ where l + b = n, 0 < a < b < 1, 0 < e 1, u, v, k are the real parameters and n = 2k, k an integer positive. Applying the Abelian integral method [Blows TR, Perko L...

Given the subtlety of tutorial tactics, identifying effective pedagogical tactical rules from human tutoring dialogues and implementing them for dialogue tutoring systems is not trivial. In this work, we used reinforcement learning (RL) to automatically derive pedagogical tutoring dialog tactics. Past research has shown that the choice of the features significantly affects the effectiveness of ...

In a continuous time random walk (CTRW), a random waiting time precedes each random jump. The CTRW model is useful in physics, to model diffusing particles. Its scaling limit is a time-changed process, whose densities solve an anomalous diffusion equation. This paper develops limit theory and governing equations for cluster CTRW, in which a random number of jumps cluster together into a single ...

In this paper we consider masonry bodies undergoing loads that can be represented by vector valued measures, and prove a result which is an appropriate formulation to this context of the static theorem of the limit analysis. As applications, we study the equilibrium of panels that are subjected both to distributed loads and concentrated forces, and determine equilibrated tensor valued measures....