The coexistence of different ferroelectric phases enables the tunability macroscopic properties and extensive applications from piezoelectric transducers to nonvolatile memories. Here we develop a thermodynamic model predict stability low-energy orientations boundaries between in ferroelectrics. Taking lead zirconate titanate bismuth ferrite as two examples, demonstrate that interphase are larg...

A mathematical model is presented to simulate water and solute transport in a highly viscous fluid with a water-permeable, elastic immersed membrane. In this model, fluid motion is described by Stokes flow, whereas water fluxes across the membrane are driven by transmural pressure and solute concentration differences. The elastic forces, arising from the membrane being distorted from its relaxe...

We consider boundaries of planar objects as level set distance functions and present a Riemannian metric for their comparison and analysis. The metric is based on a parameterization-invariant framework for shape analysis of quadrilateral surfaces. Most previous Riemannian formulations of 2D shape analysis are restricted to curves that can be parameterized with a single parameter domain. However...

The disclination-structural units model ~DSUM!, which was previously applied to grain boundaries in metals and a limited number of structures in the diamond cubic lattice, is extended to treat more complicated metastable structures of ^001& and ^011& symmetric tilt boundaries in diamond. These structures are described in terms of flat and faceted disclination dipole walls and screw dislocation ...

A general study is given of plane and cylindrical wave propagation of combined stress in an elastic-plastic medium. The coefficients of the governing differential equations, when written in matrix notation, are symmetric matrices and can be divided into submatrices each of which has a special form. The relations between the stresses on both sides of an elastic-plastic boundary are derived. Also...

A mathematical model for peristaltic motion of nonlinear viscous flows with elastic free boundaries is introduced. An iterative numerical method is used to solve the free boundary problem. Long wave asymptotic expansion is developed and the zeroth order approximation is used as the numerical initial condition. The existence and uniqueness of the solution for the free boundary equation derived f...

reservoir characterization plays an important role in different parts of an industrial project. the results from a reservoir characterization study give insight into rock and fluid properties which can optimize the choice of drilling locations and reduce risk and uncertainty. delineating hydrocarbon bearing zones within a reservoir is the main objective of any seismic reservoir characterization...

We present a method of calculation to simulate the propagation of acoustic and elastic waves generated by a borehole source embedded in a layered medium. The method is formulated as a boundary element technique where the Green's functions are calculated by the discrete wavenumber method. The restrictive assumptions are that the borehole is cylindrical and that its axis runs normal to the layer ...

This paper is concerned with the planning of optimal trajectories for vehicle collision avoidance with a Timed Elastic Band (TEB) framework. The avoidance trajectory is represented by a TEB which is optimized with respect to multiple partially conflicting objectives. The resulting trajectory constitutes the optimal compromise between a mere braking and a lane change maneuver that avoids the col...

Euler was the first who studied for engineering applications important problem of buckling arising in a simple, monolithic beam loaded axially by a concentrated load. As it has been shown from two solutions of the problem due to Timosenko theory, the elastic foundation increases the critical buckling load of the beam. Starting from the previous classical results, a mechanism to enhance the buck...