中文摘要：

Bottom-Up grid算法和Top-Down grid算法都是基于网格划分空间的高效匿名算法,但它们最终形成的匿名区域大小不一样,而较大的匿名区域带来的后果是通信成本的浪费和匿名时间的延迟.为了解决这个问题,在这两种算法的基础上提出了一种有效的匿名区域选择方法.该方法首先根据匿名度k的要求估算迭代次数,然后计算两种算法包含单元格的数量,最后比较单元格的数量并选择生成单元格数量最少的算法.两种算法的最优选择减少了LBS服务器和匿名器不必要的通信成本的浪费,缩小查询匿名集,从而提高了用户查询质量.

英文摘要：

Both the Bottom-Up grid and Top-Down grid are efficient anonymous algorithms based on grid-divided space, but the anonymous area that they eventually produce are not same and a larger anonymous area results in the waste of communication cost and the delay of anonymous time. In order to solve this problem, an effective selection method of anonymous area based on two algorithms is proposed. Firstly the method estimates the number of iterations according to the anonymous degree k, secondly it calculates the number of cell grids included by two algorithmsl finally the number of cell grids is compared and the algorithm that produces the minimum number of cell grids is selected. The optimal selection between two algorithms reduces the unnecessary waste of the communication cost of the LBS server and the anonymous server, shrinks the range of the query anonymous sets and improves the user＇s query quality.