We experimentally studied the propagation of coupled fluid stress waves and tube flexural waves generated through projectile impact along the axis of a water-filled tube. We tested mild steel tubes, 38–40 mm inner diameter and wall thicknesses of 0.8 mm, 6.4 mm, and 12.7 mm. A steel impactor was accelerated using an air cannon and struck a polycarbonate buffer placed on top of the water surface...

The dynamic buckling of thin isotropic thermoviscoplastic cylindrical shells compressed with a uniform axial velocity prescribed at the end faces is investigated analytically and numerically. In the first part of the paper, the stressed/deformed state of a shell is assumed to have buckled if infinitesimal perturbations superimposed upon it grow. Cubic algebraic equations are derived for both th...

assessing the behavior of composite structures which are subjected to impact loads is one of the important subjects in the field of mechanical sciences. using thin-walled tubes which collapsed and absorbed the impact energy is a well-known method to prevent damages to the other parts of the structures. in this paper, deformations, crushing length, peak load, mean force and energy absorption cap...

NBO analysis, hybrid density functional theory (B3LYP/6-311+G**) and ab initio molecular orbital (HF/6-311+G**) based methods were used to study the anomeric effects (AE), electrostatic interactions, dipole-dipole interactions and steric repulsion effects on the conformational properties of 2-methoxy- (1), 2-methylthio- (2), 2-methylseleno- (3), 2-fluoro- (4), 2-chloro- (5) and 2-bromocyclohexa...

In modern offshore installations, thin walled columns are used for energy absorption in accident situation. When this advanced offshore shock absorber is subjected to axial compressive load, plastic hinges are developed on the sides of column and the column crushes with repeatable patterns. It can absorb considerable impact energy due to large and continuous plastic deformation. This paper deve...

The axial skeleton in all vertebrates is composed of similar components that extend from anterior to posterior along the body axis: the occipital skull bones and cervical, thoracic, lumbar, sacral, and caudal vertebrae. Despite significant changes in the number and size of these elements during evolution, the basic character of these anatomical elements, as well as the order in which they appea...

Specimen centrifugation is one of the most time-consuming tasks associated with preanalytical specimen processing. We report the first clinical use and impact study of the novel centrifugation method, axial separation, using the Axial Separation Module (ASM). The ASM centrifuges medical specimens one at a time (in 1 min 9 s) in proprietary Axial Process Containers (APC). Here we report tests of...

Axial distributions of plasma and floating potentials, electron number density and the electron energy distribution function (EEDF) have been measured in the double layer (DL) region of an He discharge constriction. Excitation processes in the constriction region are studied. Using a linearization method for the nonstationary balance equations and choosing appropriate discharge conditions, ...

In this paper, the equivalent linearization method with a weighted averaging proposed by Anh (2015) is applied to analyze the transverse vibration of quintic nonlinear Euler-Bernoulli beams subjected to axial loads. The proposed method does not require small parameter in the equation which is difficult to be found for nonlinear problems. The approximate solutions are harmonic oscillations, whic...