Overestimation of precipitation frequency and duration while underestimating intensity, that is, the “drizzling” bias, has been a long-standing problem global climate models. Here we explore this issue from perspective partitioning. We found most models in Climate Model Intercomparison Project Phase 5 (CMIP5) have high convective-to-total (PC/PR) ratios low latitudes. Convective higher longer b...

The solution of partial differential equations on a parallel computer is usually done by a data parallel approach. The grid is partitioned and mapped onto the processors. However, partitioning of unstructured meshes and adaptively refined meshes in general is an NP -hard problem and heuristics are needed. In this paper a parallelisable and cheap method based on space-filling curves is analysed....

[1] This is a study to examine the impact of modeling photochemistry from aircraft emissions in an expanding plume versus at the grid scale in an atmospheric model. Differences in model treatments for a single flight occurred at all altitudes during takeoff, cruise, and landing. After 10 h, the plume treatment decreased grid-scale ozone production by 33%, methane destruction by 30%, and carbon ...

Regular grid spatial subdivision is frequently used for fast ray tracing of scanned models. Scanned models feature regular sized primitives, with a regular spatial distribution. Grids have worse performance, than other subdivision techniques, for irregular models without these characteristics. We propose a method to improve the performance of grids for rendering irregular scenes by allowing the...

The Set Partitioning in Hierarchical Trees (SPIHT) approach for still image compression proposed by Said and Pearlman [8], is one of the most efficient embedded gray image compression schemes till date. The algorithm relies on a very efficient scanning cum bit-allocation scheme for quantizing the coefficients obtained by a wavelet decomposition of an image. In this paper, we adopt this scheme t...

Abstract Although wood cross sections contain spatiotemporal information regarding tree growth, computer vision-based identification studies have traditionally favored disordered image representations that do not take such into account. This paper describes partitioning strategies preserve the spatial of cross-sectional images. Three are designed, namely grid based on pyramid matching and its v...

A simple way to avoid idle processors in implementing the multigrid method on a parallel computer is to select a proper ner grid as the new coarsest grid. For clarity, the variant of the V-cycle generated by this approach is called the U-cycle in this paper. It is proved that the U-cycle with a ner coarsest grid can have a faster convergence rate, and the coarsest grid equations of the U-cycle ...

Grid cells in the medial entorhinal cortex encode space with firing fields that are arranged on the nodes of spatial hexagonal lattices. Potential candidates to read out the space information of this grid code and to combine it with other sensory cues are hippocampal place cells. In this paper, we investigate a population of grid cells providing feed-forward input to place cells. The capacity o...

The Perona-Malik equation is a famous image edge-preserved denoising model, which is represented as a nonlinear 2-dimension partial differential equation. Based on the homotopy perturbation method (HPM) and the multiscale interpolation theory, a dynamic sparse grid method for Perona-Malik was constructed in this paper. Compared with the traditional multiscale numerical techniques, the proposed ...

Autonomous robots must be able to learn and maintain models of their environments. Research on mobile robot navigation has produced two major paradigms for mapping indoor environments: grid-based and topological. While grid-based methods produce accurate metric maps, their complexity often prohibits efficient planning and problem solving in large-scale indoor environments. Topological maps, on ...