语义网络

本條目仍然有文字尚未被翻譯成中文，條目是根據其他語言的維基百科內容進行翻譯。 歡迎您積極參與翻譯與修訂。

一个 语义网络（Semantic Network）常常被用作知识表示的一种形式。它其实是一个有向图，这个图的顶点代表概念，而边则用于表示这些概念之间的语义关系。

语义网络是machine-readable dictionary的一种常见类型。

主要的语义关系包括:

• Meronymy (A是B的一部分)
• Holonymy (B has A as a part of itself)

• Hyponymy (or troponymy) (A is subordinate of B; A is kind of B)
• Hypernymy (A is superordinate of B)

• Synonymy (A等同于B)
• Antonymy (A与B相反)

语义网络的一个例子是WordNet, 英语的一个词典（lexicon）数据库。

维基百科的链接以及关键词汇所组成的结构其实业可以被当作语义网络的一个简单例子，因为它具有下列属性：

• 文章A与文章B是相连的
• 維基百科中所使用之文章A的名字，是文章B的進入點

這類的網路包含了相當鬆散的語義關連性，但是它對於人類的探索仍然是有用的。我們可以使用語義網路來呈現邏輯上的描述，例如：Charles S. Peirce的Existential Graphs、或者是John F. Sowa的Conceptual Graphs。These have expressive power equal to or exceeding standard first-order predicate logic. Unlike WordNet or other lexical or browsing networks, semantic networks using these can be used for reliable automated logical deduction. Some automated reasoners exploit the graph-theoretic features of the networks during processing.

"Semantic Nets" were first invented for computers by Richard H. Richens of the Cambridge Language Research Unit in 1956 as an "interlingua" for machine translation of natural languages. They were developed by Robert F. Simmons at Systems Development Corporation, Santa Monica, California in the early 1960s and later featured prominently in the work of M. Ross Quillian in 1966.

思维导图可以被认为是语义网络的一种自由变体。思维导图通过颜色以及图片生成一个semantic net，从而激发人的创造力。

In the 1960s to 1980s the idea of a semantic link was developed within hypertext systems as the most basic unit, or edge, in an semantic network. These ideas were extremely influential, and there have been many attempts to add typed link semantics to HTML and XML.

请参考:

• 语义网（semantic web）
• Information space

[编辑] 外部链接

• 何为语义网络? 一段简短的历史
• WordNet® - 词汇引用系统（lexical reference system）
• ConceptNet 知识浏览器和常识推理的API（Knowledge Browser and Commonsense Inference API）
• 来自CiteSeer网站的引用