Ken Pembleton
CSC416: Artificial Intelligence Programming
10/17/16

1. "In a semantic network knowledge is represented as a graph, where the nodes in the graph represent concepts, and the links represent relations between concepts."
2. "The most important relations between concepts are subclass relations between classes, and instance relations between particular object instances and their parent class."
3. "However, any other relations are allowed, such as has-part, colour etc, allowing properties of objects(and categories of objects) to be represented."
4. "The subclass and instance relations may be used to derive new information which is not explicitly represented. We should be able to conclude that Clyde and Nellie both have a head, and are large and grey."
5. "Semantic networks normally allow efficient inheritance-based inferences using special purpose algorithms."
6. "One simple way to describe precisely the meaning of nodes and links in a semantic network is in terms of set theory. We interpret a class node as denoting a set of objects."
7. "The rest of this section will use examples based on frames, but the same points could equally be made about semantic networks. The choice between the two is largely a matter ofpreference between the way the information is visualized."
8. "Most frame systems allow you to state which properties (ie, slots) are just typical of a class, with exceptions allowed,and which must be true of all instances. The value of a property that is only typical of a class is referred to as a default value, and can be overridden by giving a different value for an instance or subclass."
9. "One way to do this is to require that the author of the frame system specifies a precedence order for parent classes.For example,by putting Circus-Animal first, this may indicate that where there’s a conflict the values should be taken from Circus-Animal rather than from Elephant."
10. "Allowing slots themselves to be frames means that we can specify various attributes of a slot. For example, we could specify that the slot owner could only take values of class person, has an inverse slot owns, and can take multiple values (as more than one person can jointly own something)."


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