Explanation
1. Important attributes :- There are two attributes shown in the diagram, instance and isa. Since these attributes support property of inheritance, they are of prime importance.
2. Relationships among attributes :- Basically, the attributes used to describe objects are nothing but the entities. However, the attributes of an object do not depend on the encoded specific knowledge.
3. Choosing the granularity of representation :- While deciding the granularity of representation, it is necessary to know the following:
i. What are the primitives and at what level should the knowledge be represented?
ii. What should be the number (small or large) of low-level primitives or high-level facts?
High-level facts may be insufficient to draw the conclusion while Low-level primitives may require a lot of storage. For example: Suppose that we are interested in following facts: John spotted Alex.
Now, this could be represented as "Spotted (agent(John), object (Alex))"
Such a representation can make it easy to answer questions such as: Who spotted Alex?
Suppose we want to know : "Did John see Sue?" Given only one fact, user cannot discover that answer.
Hence, the user can add other facts, such as "Spotted (x, y) → saw (x, y)"
4. Representing sets of objects :- There are some properties of objects which satisfy the condition of a set together but not as individual;
Example: Consider the assertion made in the sentences: "There are more sheep than people in Australia", and "English speakers can be found all over the world."
These facts can be described by including an assertion to the sets representing people, sheep, and English.
5. Finding the right structure as needed :- To describe a particular situation, it is always important to find the access of right structure. This can be done by selecting an initial structure and then revising the choice.
While selecting and reversing the right structure, it is necessary to solve following problem statements.
They include the process on how to:
• Select an initial appropriate structure.
• Fill the necessary details from the current situations.
• Determine a better structure if the initially selected structure is not appropriate to fulfill other conditions.
• Find the solution if none of the available structures is appropriate.
• Create and remember a new structure for the given condition.
• There is no specific way to solve these problems, but some of the effective knowledge representation techniques have the potential to solve them.
