论文标题
连续范围查询在移动对象上的分布式处理
Distributed processing of continuous range queries over moving objects
论文作者
论文摘要
对移动对象进行监视范围查询对于广泛的基于位置的服务至关重要。这些基于位置的服务面临的挑战必须在大量移动对象上处理大量并发范围查询。但是,现有的范围查询处理算法几乎是基于一台机器集中式的,由于内存和计算资源有限,这很难应对挑战。为了解决此问题,我们提出了一个分布式搜索解决方案,用于处理此工作中移动对象的并发范围查询。首先,提出了由全局网格索引和局部动态Mary树索引组成的分布式动态索引(DDI),以维护移动对象并支持搜索算法。接下来,基于DDI设计了分布式范围查询算法(DRQA),该算法引入了增量搜索策略,以监视随着对象的进化而监视范围查询;在此过程中,它进一步设计了一个计算共享范例,用于通过充分利用其共同计算以降低搜索成本来处理多个并发查询。最后,在纽约道路网络上模拟了三个具有不同分布的对象数据集,并引入了三种基线方法,以更充分地评估我们的建议的绩效。与最先进的方法相比,DRQA算法的初始查询成本减少了$ 22.7 \%$,增量查询成本下降了15.2%,这证明了我们方法优于现有方法。
Monitoring range queries over moving objects is essential to extensive location-based services. The challenge faced with these location-based services is having to process numerous concurrent range queries over a large volume of moving objects. However, the existing range query processing algorithms are almost centralized based on one single machine, which are hard to address the challenge due to the limited memory and computing resources. To address this issue, we propose a distributed search solution for processing concurrent range queries over moving objects in this work. Firstly, a Distributed Dynamic Index (DDI) that consists of a global grid index and local dynamic M-ary tree indexes was proposed to maintain the moving objects and support the search algorithm. Next, a Distributed Range Query Algorithm (DRQA) was designed based on DDI, which introduces an incremental search strategy to monitor the range queries as objects evolve; during the process, it further designs a computation sharing paradigm for processing multiple concurrent queries by making full use of their common computation to decrease the search cost. Finally, three object datasets with different distributions were simulated on a New York road network and three baseline methods were introduced to more sufficiently evaluate the performance of our proposal. Compared with state-of-the-art method, the initial query cost of the DRQA algorithm reduces by $22.7\%$ and the incremental query cost drops by 15.2%, which certifies the superiority of our method over existing approaches.