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集中式和P2P环境中的高效语义Web服务的发现

Efficient Semantic Web Service Discovery in Centralized and P2P Environments
课程网址: http://videolectures.net/iswc08_skoutas_eswsd/  
主讲教师: Dimitrios Skoutas
开课单位: 雅典国立技术大学
开课时间: 2008-11-24
课程语种: 英语
中文简介:
高效且可扩展的发现机制对于在语义Web上实现面向服务的体系结构至关重要。大多数当前存在的方法侧重于集中式架构,并且通常通过预先计算和存储用于所有可能的查询概念的语义匹配器的结果来处理效率。然而,这些方法在服务广告的数量和所涉及的本体的大小方面未能扩展。另一方面,本文提出了一种基于索引的高效且可扩展的语义Web服务发现方法,允许在查询时快速选择服务,适用于集中式和P2P环境。我们使用服务描述的新颖编码,允许在恒定时间内评估请求和广告之间的匹配,并且我们索引这些表示以修剪搜索空间,减少所需的比较次数。给定期望的排名函数,搜索算法可以逐步检索前k个匹配,即,计算并首先返回更好的匹配,从而进一步减少搜索引擎的响应时间。我们还展示了如何在合适的结构化P2P覆盖网络中有效地执行该搜索。通过对实际和合成数据的实验评估,证明了所提出方法的益处。
课程简介: Efficient and scalable discovery mechanisms are critical for enabling service-oriented architectures on the Semantic Web. The majority of currently existing approaches focuses on centralized architectures, and deals with efficiency typically by pre-computing and storing the results of the semantic matcher for all possible query concepts. Such approaches, however, fail to scale with respect to the number of service advertisements and the size of the ontologies involved. On the other hand, this paper presents an efficient and scalable index-based method for Semantic Web service discovery that allows for fast selection of services at query time and is suitable for both centralized and P2P environments. We employ a novel encoding of the service descriptions, allowing the match between a request and an advertisement to be evaluated in constant time, and we index these representations to prune the search space, reducing the number of comparisons required. Given a desired ranking function, the search algorithm can retrieve the top-k matches progressively, i.e., better matches are computed and returned first, thereby further reducing the search engine’s response time. We also show how this search can be performed efficiently in a suitable structured P2P overlay network. The benefits of the proposed method are demonstrated through experimental evaluation on both real and synthetic data.
关 键 词: 语义Web; 语义匹配器; 查询概念
课程来源: 视频讲座网
最后编审: 2019-05-05:lxf
阅读次数: 30