OBJECTIVES The purpose of this study was to determine the relationships among passive measures of weight-bearing dorsiflexion range of motion, non-weight-bearing dorsiflexion range of motion and dorsiflexion stiffness, thereby establishing whether they assess similar mechanical characteristics, as each measure has been implicated in injury risk during landings. DESIGN Cross-sectional study. ...

This paper deals with detennination of macroscopic fracture characteristics of random panicle systems. which represents a fundamental but little explored problem of micromechanics of quasibrittle materials. The panicle locations are randomly generated and the mechanical properties are characterized by a triangular softening forcedisplacement diagram for the interparticle links. An efficient alg...

A linearized theory of the acoustics of porous elastic formations, such as rocks, saturated with two different viscous fluids is generalized to take into account a pressure discontinuity across the fluid boundaries. The latter can arise due to the surface tension of the membrane separating the fluids. We show that the frequency-dependent bulk modulus K(omega) for wavelengths longer than the cha...

The increasing use of advanced sensing technologies for strain measurements necessitates the development of strain-based identification methodologies. In this study, a three-step neural network strategy, called direct soft parametric identification (DSPI), is presented to identify the member stiffness and damping parameters of a truss structure directly from free vibration-induced strains. The ...

This paper presents a new design of a low cost, unlubricated, self-deploying, self-locking hinge whose properties can be easily modified to meet different requirements. A particular implementation is considered, providing a hinge that is 135 mm long, 30 mm high and 45 mm wide, with a deployment moment varying between 0.1 and 0.3 Nm and a locking moment of 13 Nm. Stiffness tests have been carrie...

A dynamic analysis method is firstly presented to make up the present methods for calculating the strength of the cylindrical gear pair. The transient stress distribution and variation in the process of gear meshing can be obtained by dynamic simulation, the maximum bending stress, the maximum tooth contact stress and the corresponding worst meshing locations of the gear pair can be also accura...

A method of estimating damping parameters for multidegree-of-freedom vibration systems is outlined, involving a balance of dissipated and supplied energies over a cycle of periodic vibration. The power is formulated as the inner product between velocity and force terms, and integrated over a cycle. Conservative terms (mass and stiffness) drop out of the formulation. The displacement response an...

As many studies show, there is a relation between the tissue’s mechanical characteristics and some specific diseases. Knowing this relationship would help early diagnosis or microsurgery. In this paper, a new method for measuring the viscoelastic properties of soft materials at the microscale is proposed. This approach is based on the adoption of a microsystem whose mechanical structure can be ...

Abstract The reflection of time-harmonic waves in a waveguide with nonlinear boundary stiffness is considered applications to rods and beams. Incident at frequencies that are multiples fundamental frequency give rise reflected propagating nearfield the same frequencies. An infinite set equations developed for coefficients, which depend on amplitudes phases incident waves. Nonlinear conditions a...