“Clinical Showcase” is a series of pictorial essays that focus on the technical art of clinical dentistry. The section features stepby-step case demonstrations of clinical problems encountered in dental practice. If you would like to contribute to this section, contact editor-in-chief Dr. John O’Keefe at [email protected]. The preparation of esthetically appealing and anatomically correct impl...

We introduce new model equations to describe the dynamics of the electric polarization in a ferroelectric material. We consider a thin cylinder representing the material with thickness ε and discuss the asymptotic behavior of the time harmonic solutions to the model when ε tends to 0. We obtain a reduced model settled in the cross-section of the cylinder describing the dynamics of the plane com...

Fibers are industrially important particles that experience coupling between rotational and translational motion during sedimentation. This leads to helical trajectories that have yet to be accurately predicted or measured. Sedimentation experiments and hydrodynamic analysis were performed on 11 copper “fibers” of average length 10.3 mm and diameter 0.20 mm. Each fiber contained three linear bu...

A quasi three-dimensional numerical model is developed to study vortex-induced vibration (VIV) of two tandem flexible circular cylinders. In this model, the whole cylinder is divided into many sections along its length. The hydrodynamics of each section are represented by the solution of the two-dimensional Navier-Stokes equations. The dynamic response of the flexible cylinder is predicted by t...

A numerical investigation is presented into the relation between finite sized, inertial particle transport and entrainment in the vortex-dominated wake of a square cylinder placed in a channel at two blockage ratios and Lagrangian Coherent Structures (LCS) identified with recent Lagrangian visualization techniques. The square cylinder flow is computed with the incompressible, viscous flow solve...

We derive a one-dimensional model from the three-dimensional equations to analyze electromechanical deformations of a piezoceramic cylinder. We show that its extensional and torsional deformations are coupled if the axis of polarization at a point makes a nonzero angle with the axis of the cylinder and the projection of the polarization vector on a cross section is perpendicular to the radial l...

We show that absolute sonic band gaps produced by two-dimensional square and triangular lattices of rigid cylinders in air can be increased by reducing the structure symmetry. In the case of square lattices, symmetry reduction is achieved by a smaller diameter cylinder placed at the center of each unit cell. For triangular lattices the reduction is achieved by decreasing the diameter of the cyl...