臺灣博碩士論文加值系統

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。

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.

ABSTRACT I
摘要 II
TABLES OF CONTENTS III
LIST OF FIGURE VI
LIST OF TABLE VIII
CHAPTER 1 INTRODUCTION 1
1.1 Motivation and Goal 1
1.2 Methodology 2
1.3 Overview of Two-Level Ring Network Architecture 3
1.4 Scope and Contributions 6
1.5 Thesis Organization 7
CHAPTER 2 RELATED WORKS 9
2.1 Semantic Web 9
2.2 Resource Description Framework 10
2.3 SPARQL 11
2.4 Jena 12
2.5 Peer-to-Peer Network 12
2.6 Napster 15
2.7 Gnutella 16
2.8 Freenet 17
2.9 HyperCuP 18
2.10 Content Addressable Network 19
2.11 Chord 19
2.12 Edutella 21
2.13 RDFPeers 22
2.14 M-Ring 23
2.15 JXTA 23
CHAPTER 3 REQUIREMENT ANALYZE AND DESIGN 25
3.1 Use Cases 25
3.2 Requirements Analysis 26
3.3 Design of Two-Level Ring Network 27
3.4 Generation of Node Identifiers in Two-Level Ring 29
3.5 Message Delivery in Two-Level Ring 35
3.6 Formation of Two-Level Ring 35
3.7 Publishing and Querying RDF 46
CHAPTER 4 COMPLEXITY ANALYSIS AND SYSTEM SIMULATION 49
4.1 Complexity Analysis 49
4.2 Simulation Tools 50
4.3 Path Length for Peer Number 51
4.4 Path Length for Group Number 52
4.5 Path Length of routing type 53
CHAPTER 5 SYETEM IMPLEMENTION 55
5.1 System Architectures 55
5.2 P2P Network Layer 56
5.3 RDF Management Layer 67
5.4 Service Layer 73
5.5 Experiment 78
CHAPTER 6 CONCLUSION AND FUTURE WORK 86
6.1 Conclusion 86
6.2 Future Work 86
Reference 87

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