JPH0656579B2 - Rule block control system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a knowledge information processing system, and more particularly to a rule block control method in a system that handles rule-based knowledge.

[Conventional technology]

Conventionally, a production system that stores a plurality of rule blocks each containing at least one rule in a knowledge base, and executes inference for problem solving using the rule blocks stored in the rule-based knowledge base. In the knowledge information processing system, as shown in FIG. 3, the rule conflict resolution strategies (rule application method) 35, 36 of the rule block itself are fixedly assigned to each rule block 33, 34 of the rule type knowledge base 31. The rule inference executing means 32 executes the inference using each rule block according to the designation of the rule conflict resolution strategy inherent in each rule inference execution means 32. There are various types of rule conflict resolution strategies, such as a method of prioritizing rules, a method of executing a rule whose condition part matches first, and a method of considering the complexity of the condition part.

[Problems to be solved by the invention]

By the way, in an actual system, the same plurality of rules may be used for rule inference using different rule conflict resolution strategies. However, in the above-mentioned conventional rule block control method, since the rule conflict resolution strategy of the rule block requested to be activated is fixed to that rule block, the inference using one rule block is performed according to the rule block predetermined inference. It will be fixed according to the conflict resolution strategy.

Therefore, in the conventional system having the above-mentioned configuration,
There is no choice but to respond to the above request by preparing many rule blocks of the same type that contain the same rule but have different internal conflict resolution strategies, and by separating this use, it is wasteful because many rule blocks of the same type are required. There was a problem that there were many. In addition, it is desirable that rule-based knowledge be constructed as an organized form of expression in order to simplify its maintenance. However, in the above method, rule blocks of the same type are scattered in the knowledge base, and as a result, they are also required. There was a problem I could not answer.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a rule block control method capable of executing inference while dynamically changing and controlling one rule block according to different rule conflict resolution strategies.

[Means for solving problems]

In order to achieve the above object, the present invention provides a rule type knowledge base including a plurality of rule blocks and a method of activating a rule block stored in the rule type knowledge base to resolve a rule conflict included in a request to activate the rule block. A rule block activation control unit that controls according to the designation of a strategy, and a rule block inference execution unit that executes rule block inference under the control of the rule block activation control unit.

[Action]

The rule conflict resolution strategy of the rule block stored in the rule type knowledge base is not included in the rule block itself but is included in the activation request of the rule block. Therefore, a certain rule block is included in the rule conflict resolution strategy. When the rule block is started by the start request including the specification, the rule block start control unit controls the rule block to be used in the specified rule conflict resolution strategy, and the same rule block as the above rule block is Is activated by an activation request including a different rule conflict resolution strategy, the rule block activation control unit controls the rule block to be used in accordance with another rule conflict resolution strategy.

〔Example〕

 Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a functional block diagram of an embodiment of the present invention, in which 1 is a rule type knowledge base for storing rule type knowledge, and 2 is a rule for dynamically controlling a rule conflict resolution strategy according to a rule block activation request. The block activation control unit 3 is a rule block inference execution unit that executes rule inference in the rule block, and the rule block activation control unit 2 and the rule block inference execution unit 3 form a rule inference execution means 4.

As shown in FIG. 1, the rule-based knowledge is divided into a plurality of rule blocks 11 and 12 and stored in the rule-based knowledge base 1. The rule inference execution means 4 executes inference based on the rule type knowledge of the rule type knowledge base 1. Generally, in multi-rule block inference using a plurality of rule blocks, a certain rule block is changed to another one. A rule block invocation is generated, and rule inference is established by complexly combining a plurality of rule blocks.

When inferring rules in each of the rule blocks 11 and 12, it is necessary to resolve the rule conflict. In the above-mentioned conventional method, the conflict resolution strategy is described in the rule block to which it is applied and fixed. I was letting. On the other hand, in the present embodiment, the rule block activation control unit 2 and the rule conflict resolution strategy specification of the rule block activated by this activation request are simultaneously passed to the rule block activation control unit 2 together with the rule block activation request. Separated from the rule conflict resolution strategy.

Upon receiving the rule activation request, the rule block activation control unit 2 prepares for activation of the rule block, and allows the rule block inference execution unit 3 to refer to the designated rule conflict resolution strategy for the requested rule block. It prepares and instructs the rule block inference execution unit 3 to start execution of rule inference in the rule block. According to this instruction, the rule block inference execution unit 3 executes the rule inference in the rule block instructed to start the execution according to the rule conflict resolution strategy prepared in the rule block activation control unit 2.

Next, taking a simple rule block as an example, the operation of this embodiment will be described in more detail with reference to FIG. The second
In the figure, 21 is a rule type knowledge base, 22 is a rule block activation control unit, 23 is a rule block inference execution unit, and 24 is a rule inference execution means.

For example, one rule block R of the rule type knowledge base 21
It is assumed that B2 is composed of the following two rules.

Rule block RB2 Rule R21 IF A is a list, A is POP not THEN A which is not NIL, and it is assigned to B Rule R22 IF B is not NIL THEN B is output, and B is made NIL The above rule block RB2 is first When the conflict resolution strategy FM1 in which each matched rule is executed at most once is adopted, the first element of the list A is output. Also, the execution of each rule is not limited to once, and if the conflict resolution strategy FM that simply executes the matched rule is adopted, the last element of the list A is output. Further, if the conflict resolution strategy NUM of executing a simple rule of the IF section is adopted, all the elements of the list A will be output. In the conventional method, since any one of the conflict resolution strategies is described in the rule block RB2, the rule conflict resolution strategy of the rule block RB2 is fixed and the same rule R2 is used.
In order to realize three different functions by using the above three rule conflict resolution strategies for 1 and R22, the same rule R is used.
Although it was necessary to create three rule blocks including 21 and R22, in the present embodiment, the conflict resolution strategy is not described in the rule block, and the designation is included in the activation request of the rule block RB2. That's not the case because I chose.

The rule block RB1 in FIG. 2 is a rule block including rules R11 and R12, and the THE of rule R12
Rule block RB2 in N part Rule conflict resolution strategy FM
Includes the following activation requests to be activated in.

EXECUTE RB2 WITH FM This rule block RB1 activates the rule block RB2 by the rule conflict resolution strategy FM, but another rule block that activates the rule block RB2 includes, for example, an EXECUTE RB2 WITH NUM activation request. Then, at that time, the rule block RB2 is processed by the rule conflict resolution strategy NUM. In this way, by changing the designation of the conflict resolution strategy at the time of startup, it is possible to realize a plurality of functions using one rule block RB2.

Now, in FIG. 2, the activation of the rule block, for example, the rule block RB2 is controlled in the following order.

First, when the rule block knowledge RB 21 and the rule inference execution means 24 are executing the rule block inference using the rule block RB1, it is assumed that a request to activate the rule block RB2 is issued because the IF part of the rule R12 is established.
The activation request is passed to the rule block activation control unit 22 (). The activation request includes the designated FM of the rule conflict resolution strategy as described above.

Upon receiving the activation request, the rule block activation control unit 22 first prepares () for saving the local variables, loading other types of knowledge, etc., and activates the rule conflict resolution strategy from the activation request. And store (). That is, from the plurality of rule conflict resolution strategies prepared in advance in the rule block activation control unit 22, the rule conflict resolution strategy specified in the activation request is selected, and the rule block inference execution unit 23 can refer to it. Thus, it is held as indicated by reference numeral 25 in FIG. Then, it instructs the rule block inference execution unit 23 to start execution of inference in the rule block RB2 ().

In response to this, the rule block inference execution unit 23 executes the inference in the rule block RB2 with reference to the rule conflict resolution strategy 25 stored in the rule block activation control unit 22 ().

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various other additions and modifications can be made. For example, the present invention is effective in a system that handles not only rule type knowledge but also other types of frame type knowledge at the same time, and dynamic rule block control is realized when the rule block is activated by a frame type knowledge or a command from the user. it can.

〔The invention's effect〕

As described above, according to the present invention, a rule conflict resolution strategy of a rule block is not included in the rule block itself but is included in the activation request of the rule block, so that one rule block has different rule conflicts. There is an effect that inference can be executed while dynamically controlling change according to a solution strategy. Therefore, unlike the conventional case, it is not necessary to prepare a large number of rule blocks including the same rule, which reduces waste, and an expression form in which rule-type knowledge is organized can be maintained and management thereof can be simplified.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an embodiment of the present invention, FIG. 2 is an operation explanatory diagram of an embodiment of the present invention, and FIG. 3 is a functional block diagram of a conventional system. In the figure, 1, 21, 31 ... Rule type knowledge base, 2,
22 ... Rule block activation control unit, 3, 23, 32 ... Rule block inference execution unit, 4, 24 ... Rule inference execution means, 11, 12, 33, 34, RB1, RB2 ... Rule block, 25, 35, 36 …… Rule conflict resolution strategy.

Claims (1)

[Claims] 1. A rule-type knowledge base including a plurality of rule blocks, and a method of activating a rule block stored in the rule-type knowledge base is controlled according to designation of a rule conflict resolution strategy included in a rule block activation request. A rule block control method comprising: a rule block activation control unit that executes the rule block activation control unit; and a rule block inference execution unit that executes rule block inference under the control of the rule block activation control unit.