Presidential Young Investigators Award

这一总统青年研究人员(PYI)奖将致力于计算工程，特别是以下三个领域：算法改进，在计算流体力学和其他对流扩散系统中的应用，以及在并行超级计算机上的实现。对于二维或更多维领域问题，域分解是跨处理器划分操作和跨存储器划分数据的自然方式，因为在经过验证的串行码中使用的数据结构和算法都可以被带到具有特殊代码的并行情况下，以处理人为引入的划分边界。并行迭代算法的主要瓶颈是预条件。域分解位置的预条件处理的目标是创建独立或几乎独立的执行线程，并对太大而不适合主动核的问题进行优化的内存管理。在算法下要研究的一些问题包括：1.自适应网格化和在子域边界发生的精化级别之间的转换。2.自适应更新预条件和主动控制局部收敛速度。3.三维问题子域边界之间的过渡区域。需要解决的实现问题是：1.复杂的域几何。2.刻画超级计算机(Cray等)对域分解应用的性能。3.分领域外解技术与传统技术的比较。将应用区域分解的一些测试问题是：空气动力学建模。油藏模型、半导体器件物理模型和详细的动力学燃烧模型。

This Presidential Young Investigator (PYI) Award will be devoted to computational engineering, in particular, the following three areas will be examined: algorithmic enhancements, applications to computational fluid dynamics and other convective-diffusive systems, and implementation on parallel supercomputers. For field problems with in two or more dimensions, domain decom- position is a natural way to partition operations across proces- sors and to partition data across memories, since both the data structures and the algorithms employed in a proven serial code can be carried over to the parallel case with special code to treat the artificially introduced partitioning boundaries. The principal bottleneck to parallelizing iterative schemes is the preconditioning. The goal of preconditioning in domaindecom- position is to create independent or nearly independent threads of execution and optimal memory management of problems too large to fit in active core. Some of the issues to be examined under algorithmic include: 1. adaptive gridding and transition between levels of refinements occurring at subdomain boundaries. 2. adaptive updates of preconditioning and active control of local convergence rates. 3. transitional regions between subdomain boundaries for three dimensional problems. The implementation issues to be addressed are: 1. complex domain geometry. 2. characterizing the performance of supercomputers (Cray, etc) on domain-decomposed applications. 3. comparison between domain-decomposed out-of-core solution techniques with traditional techniques. Some of the test problems for which domain decomposition will be applied are: aerodynamics modeling. oil reservoir modeling, semi- conductor device physics modeling, and detailed kinetics combustion modeling.