Stencil computations on low dimensional grids are kernels of many scientific applications including finite difference methods used to solve partial differential equations. On typical modern computer architectures such stencil computations are limited by the performance of the memory subsystem, namely by the bandwidth between main memory and the cache. This work considers the computation of star...

We compare old single-core multi-processor systems against multi-core processors and study the question which improvements are most relevant for increasing the performance on stencil computations. Even before the multi-core era began, the bandwidth wall, the discrepancy between off-chip bandwidth requirements and system bandwidth performance, was already a significant problem. Because of the cu...

Spatial blocking is a critical memory-access optimization to efficiently exploit the computing resources of parallel processors, such as many-core GPUs. By reusing cache-loaded data over multiple spatial iterations, spatial blocking can significantly lessen the pressure of accessing slow global memory. Stencil computations, for example, can exploit such data reuse via spatial blocking through t...

In this paper we describe the repeated replacement method (RRM), a new meshfree method for computational fluid dynamics (CFD). RRM simulates fluid flow by modeling compressible fluids' tendency to evolve towards a state of constant density, velocity, and pressure. To evolve a fluid flow simulation forward in time, RRM repeatedly "chops out" fluid from active areas and replaces it with new "flat...

The haptic stencil consists of a 5 DOF haptic device and an anti-collision algorithm that acts as a geometric stencil and can be used for a variety of applications ranging from training to rapid prototyping and manufacturing. Online manipulation of a three-axis desktop milling machine was established using this setup. This work describes the algorithm design used to achieve the required perform...

A fourth-order accurate finite-volume scheme for hyperbolic conservation laws on three-dimensional (3D) cubedsphere grids is described. The approach is based on a central essentially non-oscillatory (CENO) finite-volume method that was recently introduced for two-dimensional compressible flows and is extended to 3D geometries with structured hexahedral grids. Cubed-sphere grids feature hexahedr...

an adaptive input-output linearization method for general nonlinear systems is developed without using states of the system. another key feature of this structure is the fact that, it does not need model of the system. in this scheme, neurolinearizer has few weights, so it is practical in adaptive situations.  online training of neurolinearizer is compared to model predictive recurrent training...

A new methodology to parallelize the production of micromechanical test samples from bulk materials is reported. This methodology has been developed to produce samples with typical gage dimensions on the order of 20-200 μm, and also to minimize the reliance on conventional focused ion beam fabrication methods. The fabrication technique uses standard microelectronic process methods such as photo...

Stencil computations constitute the kernel of many scientific applications. Tiling is often used to improve 11 the performance of stencil codes for data locality and parallelism. However, tiled stencil codes typically require shadow regions, whose management becomes a burden to programmers. In fact, it is often the 13 case that the code required to manage these regions, and in particular their ...

Stencil computations are widely used for solving Partial Differential Equations (PDEs) explicitly by Finite Difference schemes. The stencil solver alone -depending on the governing equationcan represent up to 90% of the overall elapsed time, of which moving data back and forth from memory to CPU is a major concern. Therefore, the development and analysis of source code modifications that can ef...