This work examines the quality factors (Q factors) of resonance associated with the axial and transverse vibrations of single-wall carbon nanotube (SWCNT) resonators through the use of molecular dynamics (MD) simulation. Specifically, the work investigates the effect of device length, diameter, and chirality, as well as temperature, on the resonant frequency and quality factor of these devices ...

This paper describes the digital control of a vibratory pile driver in which the vibration is generated via two tandem pairs of electrically driven, geared, contra-rotating eccentrics. Experimental results are included to show the controller-induced system dynamics for a variety of load conditions, and to highlight the fact that, if the relative phase of the eccentric pairs is not controlled, t...

This paper proposes a local approach for the on-line tuning of semi-active vibration control unit, which is set to reduce resonant response target low-order flexural modes distributed structures subject broadband stochastic disturbances. The idea have multiple self-contained units, can be fixed on thin walled and sound radiation at low audio frequencies where dynamics controlled by modes. unit ...

This paper has proposed a model that reflects process of energy dissipation in dynamic oscillatory systems. According to the hereditary theory viscoelasticity, relationship between stress and strain is realized an integral form. At same time, weakly singular kernel heredity simultaneously describes both internal friction deformation aftereffects (creep relaxation). Application developed shown t...

This paper established the equivalent linear motion equation of TRMD. To further investigate potential application TRMD in nonlinear vibration, Bouc-wen model structure with is provided, vibration control efficacy and hysteretic characteristics main under harmonic excitation are analyzed. The results show that suppresses displacement while loop energy dissipation capacity itself reduced. For so...

A new method is developed for reducing train–induced floor vibrations in buildings. Vibration transmitted through building columns to the upper floors can be mitigated by considerably increasing the thickness of a lower floor, which is named the “blocking floor”. This can be a desirable and inexpensive solution for vibration mitigation. The work presented by this paper shows the ability of an i...

This paper presents a study on active detection of internal damage based on numerical analysis of vibration dynamics in composites. Damageinduced variations of dynamic parameters are investigated both numerically and experimentally. Finite element method (FEM) is used to compute the modal parameters of composites with or without damages. Natural frequency, modal displacement, modal strain and s...

MECHANICAL . . . . . . . . . . . . . . 6 i. Transport . . . . . . . . . . . . . 6 ii. Connections . . . . . . . . . . . . 6 iii. Mounting . . . . . . . . . . . . . 6 iv. Storage . . . . . . . . . . . . . . 6 v. Shock and Vibration . . . . . . . . . . 6 ENVIRONMENTAL . . . . . . . . . . . . 6 i. EM Radiation . . . . . . . . . . . . 6 ii. Magnetic Fields . . . . . . . . . . . 6 iii. Atmospheric c...