模糊關聯式資料庫及其應用

Fuzzy Relational Databases and Its Applications

洪于強(Yu-Chiang Hung)

指導教授 ： 林志民

元智大學/工程學院/電機工程學系/碩士(2002年)

摘要

在真實的世界當中，許多的資訊系統與應用方面，都存在著各種不精確與模糊性質的資料，然而，模糊邏輯理論是一個廣泛被使用於彈性化處理模糊性質資料的工具，且可提供一個類似自然語言介面的人性化概念資料處理，在資料庫領域當中，資料的彈性化檢索能力便是一個具體的實行方法。
本文提出模糊關聯式資料庫的應用實例，並以近似估測及可能性估測的方式來作為處理不精確資料的方法。我們利用架構在模糊估測的彈性化檢索技術來實現資料庫的可能性或近似性檢索能力，分別以可擴展式標示語言(XML)文件檢索及決策分析這兩個應用實例來實現彈性化檢索技術。
在可擴展式標示語言的文件檢索方面，本文提出一個模糊查詢語言(XML-FQL)，用於可擴展式標示語言的文件檢索技術，透過此技術，我們能在可擴展式標示語言的文件中，檢索一些相似性質的資料並作近似度排序。而在決策分析應用方面，我們應用模糊邏輯理論來作彈性化檢索，在資料庫中合併專家們提出的意見來作為決策分析的依據。

關鍵字

模糊 ； 資料庫

並列摘要

In the real world, many information systems and applications must deal with imprecise or vague data. For such systems, fuzzy logic theory is well-known to provide a framework for modeling flexibility and handling vagueness in the interface between human conceptual categories and data, which is similar to the natural language. Such capabilities have been already developed in the database field, especially for handling flexible queries.
In this thesis, we present the applications of fuzzy relational databases using similarity-based and possibility-based approaches to handle imprecise information. With two cases for XML documents retrieval and decision making, we propose a fuzzy XML query language, an extension of XML-QL called XML-FQL, for XML documents retrieval and apply flexible query based on the fuzzy measure approaches to realize the possibility retrieval.
For the case of XML documents retrieval, the XML-FQL we proposed is a well-defined fuzzy query language for XML documents to handle some of element or attribute values that are more similar and allow the functions of flexible query to retrieve an ordered list by similarity. For the case of decision making, we have applied fuzzy theory to perform some flexible queries for merging many different opinions gathered from various experts’ questionnaires.

並列關鍵字

Fuzzy ； Databases

參考文獻

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