As one of the popular interoperability technology, CORBA provides a distributed computing environmentfor enterprise application system. Although CORBA makes the development of the distributed S application moreconveni...As one of the popular interoperability technology, CORBA provides a distributed computing environmentfor enterprise application system. Although CORBA makes the development of the distributed S application moreconvenient and rapid, it does not define a separate process management service to manage and control the server pro-cesses of the ORB domain. Conforming to the CORBA 2. x specification, this paper analyzes the features and the ba-sic mechanisms of the process deployment for cluster servers in the distributed computing environment, and presentsa design of process management model by integrating SAD and SMD. In particular, the dynamic extension technologyand how SMD locates- SAD are also discussed in the paper.展开更多
文摘动态路网k近邻(kNN)查询是许多基于位置的服务(LBS)中的一个重要问题。针对该问题,提出一种面向动态路网的移动对象分布式kNN查询算法DkNN(Distributed kNN)。首先,将整个路网划分为部署于集群中不同节点中的多个子图;其次,通过并行地搜索查询范围所涉及的子图得到精确的kNN结果;最后,优化查询的搜索过程,引入查询范围剪枝策略和查询终止策略。在4个道路网络数据集上与3种基线算法进行了充分对比和验证。实验结果显示,与TEN~*-Index(Tree dEcomposition based kNN~*Index)算法相比,DkNN算法的查询时间减少了56.8%,路网更新时间降低了3个数量级。DkNN算法可以快速响应动态路网中的kNN查询请求,且在处理路网更新时具有较低的更新成本。
文摘As one of the popular interoperability technology, CORBA provides a distributed computing environmentfor enterprise application system. Although CORBA makes the development of the distributed S application moreconvenient and rapid, it does not define a separate process management service to manage and control the server pro-cesses of the ORB domain. Conforming to the CORBA 2. x specification, this paper analyzes the features and the ba-sic mechanisms of the process deployment for cluster servers in the distributed computing environment, and presentsa design of process management model by integrating SAD and SMD. In particular, the dynamic extension technologyand how SMD locates- SAD are also discussed in the paper.
