1PM: Oleg Viro (Stony Brook). Multifields (fields with multivalued addition), base fields of tropical geometries. Abstract:In many classical number sets (e.g., complex numbers, real numbers and non-negative real numbers), there are remarkable structures of multifield. Replacing the tropical max-plus semifield in the foundations of tropical geometry by a multifield simplifies the structure of tr...

We report a new finite-difference time-domain (FDTD) computational model of the lasing dynamics of a four-level two-electron atomic system. Transitions between the energy levels are governed by coupled rate equations and the Pauli Exclusion Principle. This approach is an advance relative to earlier FDTD models that did not include the pumping dynamics, or the Pauli Exclusion Principle. Further,...

Anterior communicating artery (ACoA) aneurysms are well documented to have a higher rupture risk compared with aneurysms at other locations. However, the risk predicting factors for these aneurysms still remain unclear due to the complex arteries geometries and flow patterns involved. The authors introduce a comprehensive method to quantitatively illustrate the development of ACoA aneurysms usi...

We have developed a simulation capability to model multiscale flow and transport in complex biological systems based on algorithms and software infrastructure developed under the SciDAC APDEC CET. The foundation of this work is a new hybrid fluid-particle method for modeling polymer fluids in irregular microscale geometries that enables long-time simulation of validation experiments. Both conti...

Since a large amount of nanopores exist in tight oil reservoirs, fluid transport in nanopores is complex due to large capillary pressure. Recent studies only focus on the effect of nanopore confinement on single-well performance with simple planar fractures in tight oil reservoirs. Its impacts on multi-well performance with complex fracture geometries have not been reported. In this study, a nu...

Computational methods for electromagnetic and light scattering can be used for the calculation of optical forces and torques. Since typical particles that are optically trapped or manipulated are on the order of the wavelength in size, approximatemethods such as geometric optics or Rayleigh scattering are inapplicable, and solution or either the Maxwell equations or the vector Helmholtz equatio...