概率XML文件是概率数据的网络数据交换和表示标准,元素取值及其概率的查询与计算是概率XML文件的重要研究内容.概率XML文件树是一种有效的概率XML文件的数据模型,定义了概率XML文件树的基本路径和扩展路径,提出了根据可能世界原理将概率XML文件树分解为普通子XML树的集合的算法,根据路径分析原理将概率XML文件树分解为子概率XML树的集合的算法和相应的查询与计算结点及结点集合概率的算法,并通过实验进行了比较分析.实验结果表明:这两种方法是有效的；与前一种方法比较,后一种方法适合较大的概率XML文件树、结点及结点集合的概率的查询,计算过程较简单.%The computation on the polar regions plays an crucial role in the design of global numerical weather prediction (NWP) models, which details itself in the following two aspects: the particular treatment of polar regions in the model's dynamic framework and the load-balancing problem caused by the parallel data partitioning strategies. The latter has become the bottleneck of massive parallelization of NWP models. To address this problem, a novel spherical data partitioning algorithm based on the weighted-equal-area approach is proposed. The weight describes the computational distribution across the entire sphere. The new algorithm takes the collar amount and the weight function as its parameters and performs the spherical partitioning as follows: the north and the south polar regions are partitioned into a singular subdomain; then the remaining sphere surface is partitioned into some collars along the latitude; and finally each collar is partitioned into subdomains along the longitude. This partitioning method can result in two polar caps plus a number of collars with increasing partition counts as we approach the equator. After a theoretical analysis of the quality relevant to the partition performed by the algorithm, we take the PSTSWM, which is a spectral shallow water model based on the spherical harmonic transform technique, as our test-bed to validate our method. The preliminary results indicate that the algorithm can result in good parallel load balance and a promising prospect can be expected for its application within the global atmospheric model of GRAPES.
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