The water entry of a three-dimensional smooth body into initially calm water is examined. The body can move freely in its 6 d.f. and may also change its shape over time. During the early stage of penetration, the shape of the body is approximated by a surface of double curvature and the radii of curvature may vary over time. Hydrodynamic loads are calculated by the Wagner theory. It is shown th...

AIMS/BACKGROUND This study was carried out to assess the accuracy of the EyeSys videokeratoscope by using convex ellipsoidal surfaces of known form. METHODS PMMA convex ellipsoidal buttons were calibrated using Form Talysurf analysis which allowed subsequent calculation of the vertex radius and p value of the surface. The EyeSys videokeratoscope was used to examine the same ellipsoids. The ta...

Displacement measurement was conducted on compact normal and shear specimens made of acrylic homogeneous material subjected to mixed-mode loading by digital image correlation. The intelligent hybrid method proposed by Nishioka et al. was applied to the stress-strain analysis near the crack tip. The accuracy of stress-intensity factor at the free surface was discussed from the viewpoint of both ...

A Particle Swarm Optimization Toolbox (PSOt) for use with the Matlab scientific programming environment has been developed. PSO is introduced briefly and then the use of the toolbox is explained with some examples. A link to downloadable code is provided. I. GENERAL INFORMATION A. Particle Swarm Optimization Toolbox (PSOt), Summary of Included Files Main files: 1) PSO – finds min/max of arbitra...

To obtain complex part geometries at one pass using machining processes, it is important to employ the tools with non-conventional geometries. A circular paraboloid a solid of revolution, which can be obtained by rotating parabola. The swept volume an end mill defined as unification all sets points on tool for every instant moves, and its derivation obligation determine machined geometry prior ...

This study presents a hybrid method based on artificial neural network (ANN) and micro-mechanics for the failure prediction of IM7/8552 unidirectional (UD) composite lamina under triaxial loading. The ANN is trained offline by numerical data from high-fidelity micromechanics-based representative volume element (RVE) model using finite (FEM). RVE adopts identified constituent parameters inverse ...

The deformation patterns and failure mechanisms of pressurised cavities at shallow depth are relevant to many geotechnical applications, including tunnelling horizontal directional drilling. In this paper, an experimental study a reduced-scale cavity under geostatic stress is presented, in order measure the effect length, vertical soil density on failure. X-ray computed tomography used acquire ...