Sulfur accelerates coarsening of Ag nanoislands on Ag(100) at 300 K, and this effect is enhanced with increasing sulfur coverage over a range spanning a few hundredths of a monolayer, to nearly 0.25 monolayers. We propose that acceleration of coarsening in this system is tied to the formation of AgS(2) clusters primarily at step edges. These clusters can transport Ag more efficiently than can A...

A semi-coarsened multigrid algorithm with a point block Jacobi, multi-stage smoother for second-order upwind discretizations of the two-dimensional Euler equations which produces convergence rates independent of grid size for moderate subsonic Mach numbers is presented. By modification of this base algorithm to include local preconditioning for low Mach number flows, the convergence becomes lar...

Plastic rearrangements play a crucial role in the characterization of soft-glassy materials, such as emulsions and foams. Based on numerical simulations of soft-glassy systems, we study the dynamics of plastic rearrangements at the hydrodynamic scales where thermal fluctuations can be neglected. Plastic rearrangements require an energy input, which can be either provided by external sources, or...

The presence of an 'underfill' encapsulant between a micro-electronic device and the underlying substrate is known to substantially improve the thermal fatigue life of flip-chip solder joints, primarily due to load-transfer from the solder to the encapsulant. In this study, a new single joint-shear (SJS) test, which allows the measurement of the strain response of an individual solder ball duri...

We apply a multigrid reduction-in-time (MGRIT) algorithm to hyperbolic partial differential equations in one spatial dimension. This study is motivated by the observation that sequential time-stepping is a computational bottleneck when attempting to implement highly concurrent algorithms, thus parallel-in-time methods are desirable. MGRIT adds parallelism by using a hierarchy of successively co...

Coarsening of solutions of the integro-differential equation