Semantic Analysis : Producing a syntactic parse of a sentence is only the first step toward understanding it. We must still produce a representation of the meaning of the sentence. Since understanding is a mapping process, we must define the language into which we are trying to map. There is no single, definitive language in which all sentence meanings can be described. The main purpose of semantic processing is the creation of a target language representation of a sentence’s meaning, there is another important role that it plays. It imposes constraints on the representations that can be constructed, and because of the structural connections that must exist between the syntactic structure and the semantic one, it also provides a way of selecting among competing syntactic analysis. Semantic processing can impose constraints because it has access to knowledge about what makes sense in the real world.
Lexical Processing :
The first step in any semantic processing system is to look up the individual words in a dictionary or lexicon and extract their meanings. Unfortunately, many words have several meanings, and it may not be possible to choose the correct one just by looking at the word itself. For example, the word ‘diamond’ might have the following set of meanings:
- A geometrical shape with four equal sides
- A baseball field
- An extremely hard and valuable gemstone
Because of this ambiguity, the fifth generation computers which are based on artificial intelligence algorithms partially failed.