JPS63245528A - Rule block control system - Google Patents

Abstract

PURPOSE:To execute inference while dynamically changing and controlling one rule block in accordance with different rule contention resolving strategies, by providing a rule block start control part and determining a rule contention resolving strategy in accordance with a rule block start request. CONSTITUTION:When receiving the rule start request, a rule block start control part 2 of a rule inference executing means 4 prepares for rule start and prepares a designated rule contention resolving strategy concerning the requested rule block so that a rule block inference executing part 3 can refer to this strategy, and the executing means 4 instructs the executing part 3 to start execution. Then, the executing part 3 executes rule inference in rule blocks 11, 12 stored in a rule type knowledge base 1 in accordance with the prepared rule contention resolving strategy. Thus, one rule block is dynamically changed and controlled in accordance with different rule contention resolving strategies to execute inference, and the constitution is prevented from being made large-sized because it is unnecessary to provide the same rule blocks different in strategy which are required for fixed rule blocks.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a knowledge information processing system, and particularly to a control method for a rule processor in a system that handles rule-based knowledge.

(Prior Art) Conventionally, a plurality of rule blocks each containing at least one rule are stored in a knowledge base, and the rule blocks stored in this rule-type knowledge base are used to make inferences for problem solving. In a knowledge information processing system such as a production system to be executed, each rule block 33 of a rule-based knowledge base 31, as shown in FIG.
．． 34 has the rule conflict resolution strategy (rule common method) of the rule block itself fixedly specified in 35. I was performing inference using . Note that the rule conflict resolution strategy includes a method of prioritizing rules and a method of executing the rule whose condition part matches first.

Various methods exist, including methods that take into account the complexity of the conditional part.

[Problem that the invention seeks to solve]

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 conventional rule block control method described above, the specification of the rule conflict resolution strategy of the rule block requested to be activated is fixed to that rule block, so inference using one rule block is based on the rule block specified. It will be fixed according to the conflict resolution strategy.

For this reason, in the conventional method that adopts the above configuration,
The only way to meet the above request is to prepare a large number of the same type of rule blocks that contain the same rules but have different conflict resolution strategies, and to separate their usage, which is wasteful as it requires a large number of the same type of rule blocks. The problem was that there were a lot of In addition, it is desirable that rule-based knowledge be constructed in an organized expression format to simplify its maintenance and management, but the above method results in the same type of rule blocks being scattered on the knowledge base, which does not meet this requirement. There was a problem that could not be answered.

The present invention has been made in view of these circumstances,
The purpose is to provide a rule processing control method that can perform 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-based knowledge base including a plurality of rule blocks, and a rule conflict resolution included in the activation request of the rule block, and a method for activating the rule blocks stored in the rule-based knowledge base. It is composed of a rule block activation control section that performs control according to the specification of a strategy, and a rule block inference execution section that executes the rule block ttI theory under the control of the rule block activation control section.

[Effect]

Since the rule conflict resolution strategy for a rule block stored in a rule-based knowledge base is not included in the rule block itself, but is included in the activation request for that rule block, specifying the rule conflict resolution strategy that the constituent rule block consists of is not included in the rule block itself. If the rule block is started with a start request containing the rule block, the rule block start control unit controls the rule block to be used in the specified rule conflict resolution strategy, and the rule block that is the same as the above rule block is different from the above rule block. When a rule block is activated by an activation request that includes the specification of a 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-based knowledge base that stores rule-based knowledge, and 2 is a rule that dynamically controls 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 within a rule block, and the rule block inference execution unit 4 is constituted by the rule block activation control unit 2 and the rule block inference execution unit 3.

The rule-based knowledge is divided into a plurality of rule blocks 11, 12 and stored in the rule-based knowledge base 1, as shown in FIG. The rule inference execution means 4 executes inference based on the rule type knowledge of this rule type knowledge base l. Generally, in multi-rule block inference using a plurality of rule blocks, other rules are A block activation request is generated, and rule inference is established by complexly combining a plurality of rule blocks.

During rule inference within each rule block 11.12,
It becomes necessary to resolve conflict between rules, and in the conventional method described above, the strategy for conflict resolution is written in the rule block to which it is applied, and is held in a fixed manner. In contrast,
In this embodiment, a configuration is adopted in which a rule block activation request and the specification of the rule conflict resolution strategy of the rule block activated by this activation request are simultaneously passed to the rule block activation control unit 2, and the rule block and its rule conflict resolution strategy are passed to the rule block activation control unit 2. and are separated.

When the rule block activation control unit 2 receives a rule activation request, it prepares for activation of the rule block and also allows the rule block inference execution unit 3 to refer to the specified rule conflict resolution strategy for the requested rule block. It then instructs the rule block inference execution unit 3 to start executing the rule inference within that rule block. In response to this instruction, the rule block inference execution unit 3 executes the rule inference within the rule block for which execution start has been instructed, according to the rule conflict resolution strategy prepared in the rule block activation control unit 2.

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

Example Assume that one rule block RB2 of the Everrule type knowledge base 21 is composed of the following two rules.

Rule block RB2 Rule R21 1F A is a list and A is not NIL THEN Assign A to p a p L, B Rule R
22 IF B is not NIL THEN Outputs B and sets B to NIL If the above rule block RB2 adopts the conflict resolution strategy FMI in which each rule executes the first matched rule at most once, then
Output the first element of list A. Furthermore, if a conflict resolution strategy FM is adopted in which each rule is not executed only once, but the matched rules are simply executed, the last element of list A is output.

Furthermore, if the conflict resolution strategy NtJM is adopted, which is to execute a simple rule in the IF section, all elements in the list will be output. In the conventional method, the rule block R
Since the designation of one of these conflict resolution strategies was written in BZ, the rule conflict resolution strategy of rule block RB2 is fixed, and the above three types of rule conflicts are applied to the same rules R21 and R22. In order to realize three different functions using the resolution strategy, the same rules R21 and R2
It was necessary to create three rule blocks including RB2, but in this example, it was decided not to write the conflict resolution strategy in the rule block, but to include its specification in the activation request of rule block RB2. So, that kind of thing will no longer happen.

Rule block RBI in FIG. 2 is a rule block that includes rule R11 and rule R12, and the T HE N part of rule R12 includes the following activation request to activate rule block RB2 using the rule conflict resolution strategy FM. ing.

EXECUTE RB2 WITHFM This rule block RBI starts rule block RB2 with the rule conflict resolution strategy FM, but rule block R
For example, if another rule block that starts B2 includes a request to start EXECUTE RB2 WITHNUM, then rule block RB
2 will be processed using the rule conflict resolution strategy NUM. In this way, by changing the specification of the conflict resolution strategy at startup, a plurality of functions can be realized using one rule block RB2.

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

First, the rule type knowledge base 21 and the rule inference execution means 2
4, during the execution of rule block inference using rule block RBI, if the IF part of rule R12 is established and a request to activate rule block RB2 is issued, the activation request is passed to rule block activation control section 22. (3) This activation request also includes the designated FM of the rule conflict resolution strategy, as described above.

When the rule block activation control unit 22 receives the activation request, it first prepares for the activation of the rule block (■) by saving local variables, loading other forms of knowledge, etc., and also executes the rule conflict resolution strategy in response to the activation request. Separate and store (■
), that is, the rule conflict resolution strategy specified in the activation request is selected from a plurality of rule conflict resolution strategies prepared in advance in the rule block activation control unit 22, and the rule block inference execution unit 23 refers to this. It is held as indicated by reference numeral 25 in FIG. 2 for as long as possible. Then, the rule processor instructs the inference execution unit 23 to start executing the inference in the rule block RBZ (■).

In response to this, the rule block inference execution unit 23 executes inference within the rule block RBZ while referring 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 only to the above embodiments, and various other additions and changes are possible. The present invention is also effective in systems, and dynamic control of rule blocks can be realized when the rule blocks are activated by frame-type knowledge or commands from the user.

〔Effect of the invention〕

As explained above, according to the present invention, a rule conflict resolution strategy for a rule block consisting of a rule block is not included in the rule block itself, but is included in the activation request of the rule block, thereby allowing one rule block to resolve different rule conflicts. This has the effect of allowing inference to be executed while dynamically controlling changes according to the strategy. Therefore, unlike in the past, there is no need to prepare many rule blocks containing the same rules, which reduces waste, and since rule-based knowledge is expressed in an organized manner, its maintenance and management can be simplified. .

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of the operation of the 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.
RB 1. RB 2...Rule block, 25.3
5.36... Rule conflict resolution strategy. FIG. 1 is a functional block diagram of the embodiment of the present invention. FIG. 3 is a functional block diagram of the conventional system. FIG. 2 is an explanatory diagram of the operation of the embodiment of the present invention.

Claims (1)

[Claims] A rule-based knowledge base including a plurality of rule blocks, and a method for activating the rule blocks stored in the rule-based knowledge base in accordance with a specification of a rule conflict resolution strategy included in a rule block activation request. 1. A rule block control method comprising: a rule block activation control section that controls; and a rule block inference execution section that executes rule block inference under control of the rule block activation control section.