It is well known that the harmonic oscillator model can be employed for weakly excited mechanical systems. When excitation grows, anharmonicity begins to noticeable and more sophisticated models should used.

This paper describes a fast harmonic estimation, referred to Delta Adjustment (DA), using a low resolution pitch. The presented DA method is based on modification of the Generalized Dual Excitation (GDE) technique [1] which was proposed to improve speech enhancement performance. We introduce the GDE technique and modify it to be suitable for low bit rate harmonic coding that uses only an intege...

Using iterative evaluation of the real-time path integral expression, we calculate four-time correlation functions for one-dimensional systems coupled to model dissipative environments. We use these correlation functions to calculate response functions relevant to third order infrared or seventh order Raman experiments for harmonic, Morse, and quadratic-quartic potentials interacting with harmo...

In present paper we develop an analytic theory for the harmonic generation of symmetric diatomic molecular ions beyond two-level model, emphasizing the influence of charge-resonance (CR) states those are strongly coupled to electromagnetic fields for large internuclear distance. With taking into account the continuum states that is ignored in the two-level model and become important for intense...

We present a harmonic generation experiment using liquid H(2)O and D(2)O interrogated by a mid-infrared, 3.66 mum, laser at a maximum intensity of 8x10(13) W/cm(2). The unique aspects of the experiment include the long wavelength and short (9 cycle-110 fs) pulse duration of the laser as well as the near-resonant excitation of the H(2)O and D(2)O vibrational modes. We observe up to the 13th harm...

In this paper we present a novel concept to efficiently harvest vibrational energy at low frequencies and very small displacement. We describe evaluate an electromagnetic harvester which generates power from magnetic circuit with motion induced variations of air gap. External vibrations induce oscillations the gap length around equilibrium point, due linear spring counteracting force. The relat...

In this work, the nonlocal elastic waves in a fluid conveying armchair thermo elastic single walled carbon nanotube under moving harmonic load is studied using Eringen nonlocal elasticity theory via Euler Bernoulli beam equation. The governing equations that contains partial differential equations for single walled carbon nanotube is derived by considering thermal and Lorenz magnetic force. The...

This paper presents a finite element formulation for the dynamics analysis of the steady and transient states of a nonlinear piezoelectric beam. A piezoelectric beam with damping is studied under harmonic excitation. A numerical method is used for this analysis. In the paper, the central difference formula of four order is used and compared with the central difference formula of two order in th...

In this study, nonlinear vibration of axially moving strings in thermal environment is investigated. The vibration haracteristics of the system such as natural frequencies, time domain response and stability states are studied at different temperatures. The velocity of the axial movement is assumed to be constant with minor harmonic variations. It is presumed that the system and the environment...