中文摘要：

为提高P2P空间矢量数据索引网络的性能，在已有混合结构P2P空间索引网络的基础上，引入缓存机制，并提出了一种新的面向多图层的空间矢量数据缓存更新策略。该策略针对空间矢量数据多图层特性，综合考虑图层优先级以及查询频率对于缓存更新的影响，合理地利用了缓存空间。同时，将缓存更新抽象成0/1背包问题的数学模型，采用遗传算法对其优化求解。仿真结果表明该缓存更新策略可以增加缓存命中率，提高空间索引效率。

英文摘要：

In order to promote the performance of P2P spatial indexing network on vector data,a caching mechanism is introduced into the existing hybrid P2P spatial indexing network.And a novel cache replacement strategy for space vector data of multi-layer is proposed.In allusion to the multi-layer characteristics of the spatial vector data,the layer priority and query frequency are considered,which make full use of the cache space.Furthermore,the cache replacement is abstracted as a mathematical model of the 0/1 knapsack problem and solved by genetic algorithms.The simulation experiments indi-cate that this strategy can increase the caching hit ratio and improve the indexing efficiency effectively.