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Parallel mesh management using interoperable tools

Devine, Karen D.

This presentation included a discussion of challenges arising in parallel mesh management, as well as demonstrated solutions. They also described the broad range of software for mesh management and modification developed by the Interoperable Technologies for Advanced Petascale Simulations (ITAPS) team, and highlighted applications successfully using the ITAPS tool suite.

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Expanding the Trilinos developer community

Heroux, Michael A.

The Trilinos Project started approximately nine years ago as a small effort to enable research, development and ongoing support of small, related solver software efforts. The 'Tri' in Trilinos was intended to indicate the eventual three packages we planned to develop. In 2007 the project expanded its scope to include any package that was an enabling technology for technical computing. Presently the Trilinos repository contains over 55 packages covering a broad spectrum of reusable tools for constructing full-featured scalable scientific and engineering applications. Trilinos usage is now worldwide, and many applications have an explicit dependence on Trilinos for essential capabilities. Users come from other US laboratories, universities, industry and international research groups. Awareness and use of Trilinos is growing rapidly outside of Sandia. Members of the external research community are becoming more familiar with Trilinos, its design and collaborative nature. As a result, the Trilinos project is receiving an increasing number of requests from external community members who want to contribute to Trilinos as developers. To-date we have worked with external developers in an ad hoc fashion. Going forward, we want to develop a set of policies, procedures, tools and infrastructure to simplify interactions with external developers. As we go forward with multi-laboratory efforts such as CASL and X-Stack, and international projects such as IESP, we will need a more streamlined and explicit process for making external developers 'first-class citizens' in the Trilinos development community. This document is intended to frame the discussion for expanding the Trilinos community to all strategically important external members, while at the same time preserving Sandia's primary leadership role in the project.

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Toward robust scalable algebraic multigrid solvers

Tuminaro, Raymond S.; Siefert, Christopher S.; Hu, Jonathan J.; Gaidamour, Jeremie G.

This talk highlights some multigrid challenges that arise from several application areas including structural dynamics, fluid flow, and electromagnetics. A general framework is presented to help introduce and understand algebraic multigrid methods based on energy minimization concepts. Connections between algebraic multigrid prolongators and finite element basis functions are made to explored. It is shown how the general algebraic multigrid framework allows one to adapt multigrid ideas to a number of different situations. Examples are given corresponding to linear elasticity and specifically in the solution of linear systems associated with extended finite elements for fracture problems.

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Drying/self-assembly of nanoparticle suspensions

Grest, Gary S.; Cheng, Shengfeng C.; Lechman, Jeremy B.; Plimpton, Steven J.

The most feasible way to disperse particles in a bulk material or control their packing at a substrate is through fluidization in a carrier that can be processed with well-known techniques such as spin, drip and spray coating, fiber drawing, and casting. The next stage in the processing is often solidification involving drying by solvent evaporation. While there has been significant progress in the past few years in developing discrete element numerical methods to model dense nanoparticle dispersion/suspension rheology which properly treat the hydrodynamic interactions of the solvent, these methods cannot at present account for the volume reduction of the suspension due to solvent evaporation. As part of LDRD project FY-101285 we have developed and implemented methods in the current suite of discrete element methods to remove solvent particles and volume, and hence solvent mass from the liquid/vapor interface of a suspension to account for volume reduction (solvent drying) effects. To validate the methods large scale molecular dynamics simulations have been carried out to follow the evaporation process at the microscopic scale.

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Predictive Capability Maturity Model (PCMM)

Swiler, Laura P.; Knupp, Patrick K.

Predictive Capability Maturity Model (PCMM) is a communication tool that must include a dicussion of the supporting evidence. PCMM is a tool for managing risk in the use of modeling and simulation. PCMM is in the service of organizing evidence to help tell the modeling and simulation (M&S) story. PCMM table describes what activities within each element are undertaken at each of the levels of maturity. Target levels of maturity can be established based on the intended application. The assessment is to inform what level has been achieved compared to the desired level, to help prioritize the VU activities & to allocate resources.

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Results 8051–8075 of 9,998
Results 8051–8075 of 9,998