Inteligencia artifiacial unidad 2

ARTIFICIAL INTELLIGENCE UNIT II - REPRESENTATION OF THE KNOWLEDGE AND REASONING
OBJECTIVE 2.1 CONCEPTUAL MAPS

What is a conceptual map? Concept map is a Technical Study into the constructivism that produces significant learning by relating the concepts.

What are the characteristics of concept maps?

• Should be simple, and clearly show the relationships between concepts and / orpropositions. • Go from general to specific • They must be bright and attractive. OBJECTIVE 2.2 SEMANTIC NETWORK What is a semantic network? Is a knowledge representation in which concepts and their interrelationships are represented by a graph. If there are no cycles, these networks can be visualized as trees.

What is a node? A node is an object, so, Node = object Where an object can be representedby: 1. People 2. Animals 3. Events 4. Concepts 5. Attributes. 6. Geometric Figures 2.3 MONOTONOUS REASONING what can not handle a monotonic logic? various types of reasoning 2.4 THE LOGIC OF PREDICATES: SYNTAX, SEMANTICS, VALIDITY AND INFERENCE. It defines that it is the syntax

The syntax is the group of rules that you/they allow the correct sequences of the elements of a language programming.It defines that it is semantic It is the meaning of the words and of their combinations

OBJECTIVE 2.5 THE DEMONSTRATION AND THEIR METHODS As the demonstration test for recursion? is proved by mathematical induction recursive Here's an example: Show that if m and n are integers such that n + n2 + n3 = m + m2, then n is even solution. Suppose that n is odd. From this we get a contradictionon which the indirect demonstration? is based on the fact that if denied thesis is false, then the thesis is true (deny, deny). the best way is to show that theory is denied consistent with the assertions given in the hypothesis. Here's an example: Every even number is divisible by two. Fifteen is not divisible by two. The fifteen is not even number.

The demonstration consists of three parts,which are? 1. - knowledge that seeks to demonstrate the validity of test question. 2. - the rationale used as the basis for the demonstration. 3 - The procedure used to make the knowledge of the demonstration. Here's an example: "All the Venezuelans are beautiful" (This is general knowledge) "Marta Colomina is Venezuelan" then: "Marta Colomina is beautiful"

OBJECTIVE 2.6 THE METHOD OF RESOLUTIONOF ROBINSON What explains the Robinson’s method? The resolution method for (propositional) logic due to J.A. Robinson (1965) is well-known to be a sound and complete procedure for checking the unsatisfiability of a set of clauses. However, it appears that the completeness proofs that can be found in the literature are existence proofs that proceed by contradiction to show that if a set of clausesis unsatisfiable, then it must have a resolution refutation because otherwise a satisfying assignment can be obtained. This method has been exploited in many automatic theorem proves. The resolution principle applies to first-order logic formulas in Skolemized form. These formulas are basically sets of clauses each of which is a disjunction of literals. Unification is a key technique in proofs byresolution.

In what consist the Robinson´s method? The resolution method consists in building a certain kind of labeled DAG whose leaves are labeled with clauses in Γ and whose interior nodes are labeled according to the resolution rule. Given two clauses C = A∪{P} and C = B∪{¬P} (where P is a propositional letter, P /∈ A and ¬P /∈ B), the resolvent of C and C is the clause obtained bycancelling out P and ￢P.

Method Assume that, in a set of clauses, two clauses are contained such that an atom C appears as a positive member in the first clause and as a negative member in the second one: ~A1v~A2v ... v~AmvB1vB2v ... vBnvC, ------------------ (1) ~Cv~D1v~D2v ... v~DpvE1vE2v ... vEq, ------------------ (2) or simply,

FvC, ------- (1a) ~CvG. --------- (2a) If C is false, then (1a)...