Abstract An elastic wave in a physical beam naturally possesses many modes, such as flexural, longitudinal, and torsional. Therefore, suppression of all possible vibration modes has been rarely achieved beam-shaped periodic systems, especially at low frequencies. Here we present low-frequency complete bandgap mechanism by overlapping the flexural with longitudinal-torsional bandgap. To strength...

in this paper a new element for analysis of thin-walled structures is presented, and the effects of secondary shear stresses on longitudinal displacements are examined. since the interpolation functions are based on non-uniform torsional differential equations, the analysis of stiffness matrix is facilitated. therefore, its ability to produce accurate results with the least number of elements i...

PURPOSE Biomechanical comparison of straight DCP and helical plates for fixation of transversal and oblique tibial bone fractures were analyzed and compared to each other by axial compression, bending and torsion tests. METHOD An in vitro osteosynthesis of transverse (TF) and oblique bone fracture (OF) fixations have been analysed on fresh sheep tibias by using the DCP and helical compression...

Purpose. Comparison of monoaxial and polyaxial screws with the use of subcutaneous anterior pelvic fixation. Methods. Four different groups each having 5 constructs were tested in distraction within the elastic range. Once that was completed, 3 components were tested in torsion within the elastic range, 2 to torsional failure and 3 in distraction until failure. Results. The pedicle screw system...

An interactive computer program was developed for wing flutter analysis in the conceptual design stage. The objective was to estimate the flutter instability boundary of a flexible cantilever wing, when well defined structural and aerodynamic data are not available, and then study the effect of change in Mach number, dynamic pressure, torsional frequency, sweep, mass ratio, aspect ratio, taper ...

Presented in the paper is the design, the simulation, the fabrication and the experiment of a new z-axis resonant accelerometer based on the electrostatic stiffness. The new z-axis resonant micro-accelerometer, which consists of a torsional accelerometer and two plane resonators, decouples the sensing movement of the accelerometer from the oscillation of the plane resonators by electrostatic st...

OBJECTIVES To compare bone healing of tibial osteotomy repaired with Nitinol wire braid and hardened steel rods (Braid system) and polymethylmethacrylate bone cement with an interlocking intramedullary (IM) nail fixation in an ovine model. STUDY DESIGN In vitro and in vivo experimental study. ANIMALS Adult female sheep (n=22). METHODS Using sheep tibia, a middiaphyseal transverse osteotom...

A novel torsional wave sensor designed to characterize mechanical properties of soft tissues is presented in this work. Elastography is a widely used technique since the 1990s to map tissue stiffness. Moreover, quantitative elastography uses the velocity of shear waves to achieve the shear stiffness. This technique exhibits significant limitations caused by the difficulty of the separation betw...