Rule base processing system and rule evaluation control method therein

• US 5,204,939 A
• Filed: 12/13/1990
• Issued: 04/20/1993
• Est. Priority Date: 12/14/1989
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Yamazaki, Masami, Fukushima, Hisayo
• Primary Examiner(s): Fleming, Michael R.
• Assistant Examiner(s): Downs, Robert W.
• Application Number:
  US07/627,151
• Time in Patent Office: 859 Days
• Field of Search: 364/513, 395/51, 395/50, 395/61, 395/11
• US Class Current: 706/50
• CPC Class Codes: G06F 30/30 Circuit design
• CPC Class Codes: G06N 5/01 Dynamic search techniques; Heuristics; Dynamic trees; Branch-and-bound
• CPC Class Codes: G06N 5/046 Forward inferencing; Production systems
• CPC Class Codes: Y10S 706/921 Layout, e.g. circuit, construction

Abstract

A rule base processing system for processing rules with an inference engine is provided with a control block and a number of knowledge source blocks containing the rules. The control block contains a knowledge source list of the knowledge source blocks and a function name through which the control block may be called as a subprogram. The knowledge source blocks contain priority sequence tables in which the sequence of execution of the rules is arranged and can be externally controlled. Each rule in the knowledge source contains a number of detailed rules from which an optimum rule is selected.

Claims

1. A rule base processing system, comprising:

an inference engine;

a rule base storage, operatively connected to said inference engine, including;

knowledge source blocks having a selection mode and rules arranged in a first priority sequence, at least some of said knowledge source blocks further including a priority sequence table describing a second priority sequence of the rules, each of the rules including a condition and a procedure; and

a control block having a knowledge source list of said knowledge source blocks in said rule base storage to be executed by said inference engine; and

a rule base compiler, operatively connected to said rule base storage, to compile said rule base storage and generate a program for executing the rules in one of the first and second priority sequences, the program executing in each knowledge source block having a single rule selection mode, only the procedure of a first rule having a condition that is satisfied.

2. A rule base processing system as recited in claim 1, wherein said control block further comprises a function name designating section which stores a function name corresponding to the knowledge source blocks.

3. A rule base processing system as recited in claim 1, wherein said rule base processing system further comprises external control means for externally creating and controlling the sequence of rule evaluation.

4. A rule base processing system as recited in claim 3, wherein

said rule base processing system further comprises a terminal, operatively connected to said rule base storage, said inference engine, and said external control means, and said external control means includes:

start control means for receiving a start request from the terminal and sending an information transfer request to the terminal;

evaluation sequence control means for receiving evaluation sequence data input through the terminal in response to the transfer request; and

executing means for executing the rules using the inference engine in a sequence conforming to the evaluation sequence data.

5. A rule base processing system as recited in claim 4, wherein the evaluation sequence control data received by said evaluation sequence control means includes a rule number list, and said executing means executes the rules responsive to the sequence indicated by the rule number list.

6. A rule base processing system as recited in claim 4, wherein the evaluation sequence control data includes an application condition indicating execution or nonexecution of the rules, and wherein said executing means executes the rules in conformity with the sequence indicated by a rule number list previously stored and corresponding to the application condition.

7. A rule base processing system as recited in claim 1, wherein said control block designates a first of said knowledge source blocks in the knowledge source list to be executed by the inference engine.

8. A rule base processing system as recited in claim 1, wherein said knowledge source blocks can designate other knowledge source blocks to be executed by the inference engine on an event list.

9. A rule base processing system as recited in claim 8, wherein said other knowledge source blocks are selected from the event list by traversing an event queue in a predetermined order.

10. A method, performed by a computer system, of executing rules in a rule base source to be processed by an inference engine, said method comprising the steps of:

(a) storing the rules in knowledge blocks with said computer system;

(b) storing a list of the knowledge blocks in a control block with said computer system;

(c) storing a function name corresponding to the control block; and

(d) executing in said computer system the knowledge blocks responsive to the list, including calling a group of the knowledge blocks listed in the control block as a subroutine using the function name corresponding to the control block.

11. A method as recited in claim 10, wherein said computer system further performs the step of storing a priority sequence table in the knowledge source blocks indicating a priority sequence of the rules and executing the rules responsive to the table.

12. A method as recited in claim 10, wherein the rules contain selectable rules, and wherein said computer system further performs the steps of:

(d) evaluating the selectable rules; and

(e) selecting one of the selectable rules.

13. A method as recited in claim 10, wherein the rules each have a condition and a procedure, and wherein said computer system further performs the steps of:

(d) executing the rules in a priority sequence when a priority control is designated within said knowledge blocks;

(e) executing only the procedure of a first rule having a condition that is satisfied, when a single rule selection mode is designated within said knowledge blocks; and

(f) executing the procedure of all of the rules having a condition that is satisfied, when a multiple rule selection mode is designated.

14. A method as recited in claim 10, wherein said computer system further performs the step of designating a first of said knowledge source blocks in the knowledge source list to be executed by the inference engine.

15. A method as recited in claim 14, wherein said computer system further performs the step of (e) designating, with said knowledge source blocks, other knowledge source blocks to be executed by the inference engine on an event list.

16. A method as recited in claim 15, wherein in step (e) said computer system performs the step of selecting the other knowledge source blocks from the event list by traversing an event queue in a predetermined order.

17. A method, performed by a computer system, of compiling a rule base source including rules each having a procedure and a condition, said method comprising the steps of:

(a) determining with said computer system whether only a single procedure is to be executed when the condition is satisfied, or whether the procedure for all of the rules in which the condition is satisfied is to be executed;

(b) determining with said computer system whether the rules are to be executed in a priority conforming to a priority sequence table; and

(c) arranging executing of the rules with said computer system in accordance with the priority of the priority sequence table and the result of the determination in step (a).

18. An expert system, comprising:

rules storage storing rules;

priority storage storing an evaluation priority list indicating the priority of evaluation of the rules;

an inference engine evaluating the rules in accordance with the evaluation priority;

wherein said priority storage stores plural priority tables each including an evaluation priority list and the priority tables being selectable by a user; and

further comprising means for allowing a user to enter the evaluation priority list.

19. A rule base processing system, comprising:

an inference engine;

a rule base storage, operatively connected to said inference engine, including;

knowledge source blocks having a selection mode and rules arranged in a first priority sequence, at least some of said knowledge source blocks further including a priority sequence table describing a second priority sequence of the rules, each of the rules including a condition and a procedure; and

a control block having a knowledge source list of said knowledge source blocks in said rule base storage to be executed by said inference engine; and

a rule base compiler, operatively connected to said rule base storage, to compile said rule base storage to generate a program for executing the rules in one of the first and second priority sequences, the program executing, in each knowledge source block having a multiple rule selection mode, the procedure of all of the rules having a condition that is satisfied.