Rigid body modes are a necessary set of modes used in the development of component system models. Often these modes are difficult to obtain during modal testing due to instrumentation limitations or test difficulties. Using a combination of singular value decomposition, modal parameter estimation to purge higher order mode effects and structural dynamic modification, a set of appropriately scal...

The transient dynamics of a beam mounted on springer-damper support and equipped with a nonlinear energy sink (NES) is investigated under the effects of shock loads. The equations of motion are derived using the Hamilton’s principle leading to four hybrid ordinary and partial differential equations and descritized using the Galerkin method. An adaptive Newmark method is employed for accurate an...

The application of rotational symmetry modes to quantitative rigid-body analysis is demonstrated for octahedral rotations in Mg(H2O)6RbBr3. Rigidbody rotations are treated as axial-vector order parameters and projected using group-theoretical methods. The high-temperature crystal structure of the Mg(H2O)6RbBr3 double salt consists of a cubic perovskite-like corner-sharing network of RbBr6 octah...

the most important quality indicator of fruits is the flesh firmness which is well correlated to their young’s modulus. in this research variation of vibration characteristics (shape modes, natural frequency) of apple due to change of material characteristics (density, young's models, poisson ratio) and apple volume was investigated using finite element simulation. an image processing technique...

It is recently shown in [1, 2] that the exact analytical solution of a rigid body controlled by a linear feedback law may directly be written down in terms of eigenvalues and eigenvectors. However, this control has been computed in previous work [3] for the regulation of satellite angular momentum when the flywheels are at rest. Therefore, the method will here be extended to deal with the struc...

The need for compatibility between degrees of freedom of various elements is a major problem encountered in practice during the modeling of complex structures; the problem is generally solved by an additional rotational degree of freedom [1-3]. This present paper investigates possible improvements to the performances of strain based cylindrical shell finite element [4] by introducing an additio...