- 學位論文
設計及製作以Chord網路為基礎的分散式本體知識RDF儲存庫
Design and Implementation of an Ontology-based Distributed RDF Store Based on Chord Network
摘要
透過語意網的技術，使用者可以利用RDF所建立的後設資料層的描述，達到語意化的搜尋並且利用推理機制找出隱含的知識。RDF是目前所用來描述網路資源的方法。一個 RDF模型是由三元組的集合所構成。 在這篇論文使用了DHT的同儕網路架構來設計一個分散式的RDF儲存庫，並且將本身所分享的RDF文件經過剖析，將內部的三元組分散儲存在不同的節點內。我們針對Chord網路架構做一個延伸。利用結點中所分享的RDF檔案，對於網路上不同目的的節點做一個分類，以減少RDF三元組在Chord網路中儲存以及查詢的時間。並且針對不同個數的群組網路進行測試模擬，驗證所設計的網路結構之效能。
並列摘要
RDF and OWL are used as the data model and schema, respectively, to build the distributed knowledge base of the Semantic Web. The components in RDF models, subjects, predicates, and objects, are identified universally on the web, which makes it suitable for distributed operations. In this paper, we employ the distributed hash table (DHT) technology on peer-to-peer network to develop distributed RDF store. To take into account of ontology in RDF, we extend the chord ring to be two-level ring, where the first level is based on the ontology schema and the next one is on the RDF itself. The extension retains the complexity of O(log N) in maintaining and lookup message in an N-node system. The simulation results show that adding an additional level reduces the path length of message lookup. We design three-layered system architecture for the ontology-based distributed RDF store. We are developing a prototype according to the design in this paper to show how the two-level ring works.