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- 2017
重叠网格装配中的一种改进ADT搜索方法
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Abstract:
摘要 针对现有交替数字二叉树（ADT）方法的不足，引入辅助笛卡儿网格提出了一种基于散列数据结构的改进搜索方法以缓解可能出现堆栈溢出的问题和提高重叠网格装配的效率。该方法以散列数据结构的方式对网格单元进行存储和搜索，首先以辅助笛卡儿网格对网格单元的存储空间进行初步映像，然后基于ADT搜索树作进一步检索。在ADT搜索方法的基础上，笛卡儿网格的引入进一步缩小了网格单元的搜索范围使得改进方法具有更好的效率。基于单个网格节点，查询深度和搜索耗时的测试显示改进方法相比现有ADT搜索方法能使挖洞的平均效率提高25%以上。此外，挖洞结果和基于网格装配的数值计算验证了改进搜索方法在重叠网格装配中的可靠性。
Abstract：An improved searching method of alternating digital tree (ADT) is proposed for making up the deficiency of the existing ADT method and improving the efficiency of the overlapping grid assembly. The new method stores and retrieves donor cells based on a hash data structure, in which an auxiliary Cartesian mesh is first applied to map the storage address similar to the table of contents in hash table, and then a node-oriented ADT is used for further retrieval in accordance with the aforementioned storage space. Based on ADT search, the introduction of the Cartesian mesh can further narrow the search scope of donor cell, which makes the present one have better efficiency. Tests of searching depth and time consumption based on several discrete grid nodes indicate that the present method can enhance the average hole-cutting efficiency by more than 25% compared with the existing ADT method. Moreover, the hole-cutting results and numerical computations of typical configurations confirm the reliability of the improved ADT searching method in overlapping grid assembly.
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