Page 121 - DCAP506_ARTIFICIAL_INTELLIGENCE

Unit 9: Weak Slot and Filler Structures

As a more multifaceted instance consider the sentence: John gave Mary the book. Here we have Notes
numerous facets of an event.

Figure 9.3: A Semantic Network for a Sentence

Task Discuss the use of semantic net with example.

9.1.2 Inference in a Semantic Net

Fundamental inference method: follow links between nodes.

Two methods to perform this:
 Intersection search
 The view that spreading activation out of two nodes and locating their intersection
locates relationships between objects. This is attained by allocating a particular tag
to every visited node.

 Many benefits including entity-dependent organization and fast parallel
implementation. However very structured questions necessitate highly structured
networks.

 Inheritance
 The isa and instance representation offer a method to implement this.

Did u know? Inheritance also offers a means of dealing with default reasoning.

Example: We could represent:
 Emus are birds.
 Usually birds fly and have wings.

 Emus run.

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