GML数据的存储研究还属于一个崭新的领域,目前还没有一个比较完好的技术实现方法。在分析比较Oracle XML DB存储模式的基础上,考虑GML空间数据的特点,研究GML空间数据在Ora-cle中的存储机制,并分析储存模式的优劣。利用Oracle XML DB实...GML数据的存储研究还属于一个崭新的领域,目前还没有一个比较完好的技术实现方法。在分析比较Oracle XML DB存储模式的基础上,考虑GML空间数据的特点,研究GML空间数据在Ora-cle中的存储机制,并分析储存模式的优劣。利用Oracle XML DB实现对GML数据的存储是GIS空间数据管理方面研究的一条新的思路和途径。展开更多
For name-based routing/switching in NDN, the key challenges are to manage large-scale forwarding Tables, to lookup long names of variable lengths, and to deal with frequent updates. Hashing associated with proper leng...For name-based routing/switching in NDN, the key challenges are to manage large-scale forwarding Tables, to lookup long names of variable lengths, and to deal with frequent updates. Hashing associated with proper length-detecting is a straightforward yet efficient solution. Binary search strategy can reduce the number of required hash detecting in the worst case. However, to assure the searching path correct in such a schema, either backtrack searching or redundantly storing some prefixes is required, leading to performance or memory issues as a result. In this paper, we make a deep study on the binary search, and propose a novel mechanism to ensure correct searching path without neither additional backtrack costs nor redundant memory consumptions. Along any binary search path, a bloom filter is employed at each branching point to verify whether a said prefix is present, instead of storing that prefix here. By this means, we can gain significantly optimization on memory efficiency, at the cost of bloom checking before each detecting. Our evaluation experiments on both real-world and randomly synthesized data sets demonstrate our superiorities clearly展开更多
文摘GML数据的存储研究还属于一个崭新的领域,目前还没有一个比较完好的技术实现方法。在分析比较Oracle XML DB存储模式的基础上,考虑GML空间数据的特点,研究GML空间数据在Ora-cle中的存储机制,并分析储存模式的优劣。利用Oracle XML DB实现对GML数据的存储是GIS空间数据管理方面研究的一条新的思路和途径。
基金supported by the National Natural Science Foundation of China (Grant No. 61472130 and 61702174)the China Postdoctoral Science Foundation funded project
文摘For name-based routing/switching in NDN, the key challenges are to manage large-scale forwarding Tables, to lookup long names of variable lengths, and to deal with frequent updates. Hashing associated with proper length-detecting is a straightforward yet efficient solution. Binary search strategy can reduce the number of required hash detecting in the worst case. However, to assure the searching path correct in such a schema, either backtrack searching or redundantly storing some prefixes is required, leading to performance or memory issues as a result. In this paper, we make a deep study on the binary search, and propose a novel mechanism to ensure correct searching path without neither additional backtrack costs nor redundant memory consumptions. Along any binary search path, a bloom filter is employed at each branching point to verify whether a said prefix is present, instead of storing that prefix here. By this means, we can gain significantly optimization on memory efficiency, at the cost of bloom checking before each detecting. Our evaluation experiments on both real-world and randomly synthesized data sets demonstrate our superiorities clearly
