Abstract Quasi-periodic (QP) solutions of a damped nonlinear QP Mathieu equation with cubic nonlinearity are investigated by using the incremental harmonic balance (IHB) method two time scales. The contains incommensurate excitation frequencies, one is small frequency while other nearly equals twice linear natural frequency. It found that Fourier spectra consist uniformly spaced sidebands due t...

A mathematical model of damped flexural–torsional vibrations monoclinic composite strip constant-length rectangular cross section is proposed. The based on the refined Timoshenko beam-bending theory, theory generalized Voigt–Lekhnitskii torsion, and elastic–viscoelastic correspondence principle in linear viscoelasticity. two-stage method for solving a coupled system differential equations devel...

in this study, we have theoretically investigated designing possibility of a seismometer using fiber bragg grating (fbg) and metal bellows pairs attached on a mechanical system. this new seismometer can record earthquakes according to sensitivity of fiber optic to changes in physical parameters such as stress and strain. firstly, in order to understand the quantity and quality of sensor perform...

In scattered Swedish dialects, the vowels /i/ and /y/ are pronounced with a markedly low F2. This results in a ‘damped’ vowel quality that appears to be rather unusual in a typological perspective. To date, however, no experimental studies of this vowel type have been carried out using Swedish material. In this paper, formant frequencies are presented for one dialect suggesting that the /i/ vs....

The present paper aims at analytically evaluating the natural frequencies of cracked slender masonry elements. problem is dealt with in framework linear perturbation, and small oscillations structure are studied under loaded conditions, after equilibrium for permanent loads has been achieved. A beam element made masonry-like material considered, some explicit expressions beam's fundamental freq...

the paper investigates into the vibrational characteristics of the truck chassis including the natural frequencies and mode shapes. truck chassis forms the structural backbone of a commercial vehicle. when the truck travels along the road, the truck chassis is excited by dynamic forces caused by the road roughness, engine, transmission and more. modal analysis using finite element method (fem) ...