This Article 
   
 Share 
   
 Bibliographic References 
   
 Add to: 
 
Digg
Furl
Spurl
Blink
Simpy
Google
Del.icio.us
Y!MyWeb
 
 Search 
   
A High-Level Petri Nets-Based Approach to Verifying Task Structures
March/April 2002 (vol. 14 no. 2)
pp. 316-335

As knowledge-based system technology gains wider acceptance, there is an increasing need for verifying knowledge-based systems to improve the reliability and quality. Traditionally, attention has been given on verifying knowledge-based systems at the knowledge level, which only addresses structural errors such as redundancy, conflict, and circularity in rule bases. No semantic error such as inconsistency in the requirements specification level has been checked. In this paper, we propose the use of task structures for modeling user requirements and domain knowledge at the requirements specification level, and the use of high-level Petri nets for expressing and verifying the task structure-based specifications. Issues in mapping task structures into high-level Petri nets are identified, for example, the representation of task decomposition, constraints, and state model; the distinction between follow and immediately follow operators; and the composition operator in task structures. The verification of task structures using high-level Petri nets is performed on model specifications of a task through constraints satisfaction and relaxation techniques and on process specifications of the task based on the reachability property and the notion of specificity.

[1] K.L. Bellman, “Testing and Correcting Rule-Based Expert Systems,” Proc. Space Quality Conf., Apr. 1988.
[2] T. Bench-Capon, F. Coenen, H. Nwana, R. Paton, and M. Shave, “Two Aspects of the Validation and Verification of Knowledge-Based Systems,” IEEE Expert, pp. 76–81, Jun. 1993.
[3] A. Borning, R. Duisberg, and B. Freeman-Benson, “Constraint Hierarchies,” Proc. 1987 Conf. Object-Oriented Programming Systems, Languages, and Applications, pp. 48–60, Oct. 1987.
[4] G. Bucci and E. Vicario, “Compositional Validation of Time-Critical Systems Using Communicating Time Petri Nets,” IEEE Trans. Software Eng., vol. 21, no. 12, pp. 969–992, Dec. 1995.
[5] B. Chandrasekaran, T.R. Johnson, and J.W. Smith, “Task-Structure Analysis for Knowledge Modeling,” Comm. ACM, vol. 35, no. 9, pp. 124–137, Sept. 1992.
[6] C.L. Chang, R.A. Stachowitz, and J.B. Combs, “Validation of Nonmonotonic Knowledge-Based Systems,” Proc. IEEE Int'l Conf. Tools for Artificial Intelligence, Nov. 1990.
[7] D. Davcev and W. Burkhard, “Consistency and Recovery Control for Replicated Files,” Proc. 10th ACM Symp. Operating Systems Principles, pp. 87-96, 1985.
[8] J. de Kleer, “An Assumption-Based tms,” Artificial Intelligence, pp. 127–162, 1986.
[9] J.B. Dennis, “A Multiuser Computation Facility for Education and Research,” Comm. ACM, vol. 7, no. 9, pp. 521–529, Sept. 1964.
[10] J.B. Dennis and D.P. Misunas, “A Preliminary Architecture for a Basic Data-Flow Processor,” Twenty Five Years of the Int'l Symp. Computer Architecture (Selected Papers), pp. 125–131 1998.
[11] M. Felder, D. Mandrioli, and A. Morzenti, “Proving Properties of Real-Time Systems Through Logical Specifications and Petri Net Models,” IEEE Trans. Software Eng., vol. 20, no. 2, pp. 127–141, Feb. 1994.
[12] B.N. Freeman-Benson, J. Maloney, and A. Borning, “An Incremental Constraint Solver,” Comm. ACM, vol. 33, no. 1, pp. 54–63, Jan. 1990.
[13] S.W. French and D. Hamilton, “A Comprehensive Framework for Knowledge-Base Verification and Validation,” Int'l J. Intelligent Systems, vol. 9, no. 9, pp. 809–837, 1994.
[14] C. Ghezzi, D. Mandrioli, S. Morasca, and M. Pezze, “A Unified High-Level Petri Net Formalism for Time-Critical Systems,” IEEE Trans. Software Eng., vol. 17, no. 2, pp. 160–171, Feb. 1991.
[15] A. Ginsberg, “Knowledge-Based Reduction: A New Approach to Checking Knowledge Bases for Inconsistency and Redundancy,” Proc. Seventh Nat'l Conf. Artificial Intelligence (AAAI '88), pp. 585–589, 1988.
[16] P. Huber, K. Jensen, and R.M. Shapiro, “Hierarchies in Coloured Petri Nets,” Advances in Petri Nets 1990, G. Rozenberg, ed., pp. 313–341, 1990.
[17] K. Jensen, “Coloured Petri Nets: A High Level Language for System Design and Analysis,” Advances in Petri Nets 1990, G. Rozenberg, ed., pp. 342–416, 1990.
[18] R.H. Klenke, M. Meyassed, J.H. Aylor, B.W. Johnson, R. Rao, and A. Ghosh, “An Integrated Design Environment for Performance and Dependability Analysis,” Proc. ACM Design Automation Conf., pp. 184–189, June 1997.
[19] V. Kumar, “Algorithms for Constraint-Satisfaction Problems: A Survey,” AI Magazine, vol. 13, no. 1, pp. 32–44, Spring 1992.
[20] J. Lee, “Task Structures as a Basis for Modeling Knowledge-Based Systems,” Int'l J. Intelligent Systems, vol. 12, pp. 167–190, Mar. 1997.
[21] J. Lee and J.Y. Kuo, “New Approach to Requirements Trade-Off Analysis for Complex Systems,” IEEE Trans. Knowledge and Data Eng., vol. 10, no. 4, pp. 551–562, July/Aug. 1998
[22] J. Lee and L.F. Lai, “Verifying Task-Based Specifications in Conceptual Graphs,” Information and Software Technology, vol. 39, nos. 14/15, pp. 913–923, Feb. 1998.
[23] J. Lee, L.F. Lai, and W.T. Huang, “Task-Based Specifications Through Conceptual Graphs,” IEEE Expert, vol. 11, no. 4, pp. 60–70, Aug. 1996.
[24] J. Lee, K.F.R. Liu, and W.L. Chiang, “A Fuzzy Petri Net-Based Expert System and Its Application to Damage Assessment of Bridges,” IEEE Trans. System, Man, and Cybernetics, vol. 29, no. 3, pp. 350–370, 1999.
[25] J. Lee and N.L. Xue, “Analyzing User Requirements by Use Cases: A Goal-Driven Approach,” IEEE Software, vol. 16, no. 4, pp. 92–101, July/Aug. 1999.
[26] S. Lee and R.M. O'Keefe, “Developing a Strategy for Expert System Verification and Validation,” IEEE Trans. Systems, Man, and Cybernetics, vol. 24, no. 4, pp. 643–655, Apr. 1994.
[27] A.K. Mackworth, “Consistency in Networks of Relations,” Artificial Intelligence, vol. 8, pp. 99–118, 1977.
[28] T. Mitchel, R. Keller, and S. Kedar-Cabelli, “Explanation-Based Generalization: A Unifying View,” Machine Learning, pp. 47–80, 1986.
[29] T. Murata, “Petri Nets: Properties, Analysis and Application,” Proc. IEEE, vol. 77, no. 4, 1989.
[30] D.L. Nazareth, “Static and Dynamic Verification of Rule-Based Systems Using Digraphs,” Proc. Ninth Nat'l Conf. Artificial Intelligence AAAI '90 Workshop Verification, Validation, and Testing, July 1990.
[31] D. L. Nazareth, “Investigating the Applicability of Petri Nets for Rule-Based System Verification,” IEEE Trans. Knowledge and Data Eng., vol. 4, no. 3, pp. 402–415, June 1993.
[32] T.A. Nguyen, W.A. Perkins, T.J. Laffey, and D. Pecora, “Knowledge Base Verification,” AI Magazine, pp. 69–75, Summer 1987.
[33] E.P.D. Pednault, “Formulating Multiagent, Dynamic-World Problems in the Classical Planning Framework,” Reading about Actions and Plans Proc. 1986 Workshop, M.P. Georgeff and A.L. Lansky, eds., 1987.
[34] A.D. Preece and R. Shinghal, “Verifying and Testing Expert System Conceptual Models,” Proc. IEEE Int'l Conf. Systems, Man, and Cybernetics, vol. 1, pp. 922–927, 1992.
[35] J.R. Slagle, D.A. Gardiner, and K. Han, “Knowledge Specification of an Expert System,” IEEE Expert, vol. 5, no. 4, pp. 29–38, Aug. 1990.
[36] R.A. Stachowitz, C.L. Chang, T.S. Stock, and J.B. Combs, “Building Validation Tools for Knowledge-Based Systems,” Proc. First Ann. Workshop Space Operations Automation and Robotics, pp. 209–216, 1987.
[37] L. Steels, “Components of Expertise,” AI Magazine, vol. 11, no. 2, pp. 28–49, 1990.
[38] M. Suwa, A. Carlisle, and E.H. Shortliffe, “Completeness and Consistency in a Rule-Based System,” AI Magazine, pp. 16–21, Autumn 1982.
[39] M.C. Tanner and A.M. Keuneke, “The Roles of the Task Structure and Domain Functional Models,” IEEE Expert, vol. 6, no. 3, pp. 50–57, June 1991.
[40] A.H.M. ter Hofstead and E.R. Nieuwiand, “Task Structure Semantics Through Process Algebra,” Software Eng. J., vol. 8, pp. 14–20, Jan. 1993.
[41] W.T. Tsai, P.E. Johnson, J.R. Slagle, I.A. Zualkernan, K.G. Heisler, K. Jamal, K. Han, D. Volovik, D.A. Gardiner, and T.L.A. Yang, “Requirements Specification for Expert Systems? A Case Study,” Technical Report TR 88-44, Univ. of Minnesota, Minneapolis, 1988.
[42] W.M.P. van der Aalst and A.H.M. ter Hofstede, “Verification of Workflow Task Structures: A Petri-Net-Based Approach,” Information Systems, vol. 25, no. 1, pp. 43–69, 2000.
[43] A. van Lamsweerde, R. Darimont, and P. Massonet, “Goal-Directed Elaboration of Requirements for a Meeting Scheduler Problems and Lessons Learnt,” Technical Report RR-94-10, Univ. Catholique de Louvain, Dept. d'Informatique, B-1348 Louvain-la-Neuve, Belgium, 1994.
[44] C.H. Wu and S.J. Lee, “Enhanced High-Level Petri Nets with Multiple Colors for Knowledge Verification/Validation of Rule-Based Expert Systems,” IEEE Trans. Systems, Man, and Cybernetics, vol. 27, no. 5, pp. 760–773, Oct. 1997.
[45] J. Yen, J. Lee, and D. Hamilton, “Designing Verifiable Expert Systems,” Proc. IEEE Int'l Conf. Tools for Artificial Intelligence, pp. 878–884, Nov. 1990
[46] D. Zhang and D. Nguyen, “Prepare: A Tool for Knowledge Base Verification,” IEEE Trans. Knowledge and Data Eng., vol. 6, no. 6, pp. 983–989, Dec. 1994.

Index Terms:
verification, requirements specifications, task structures, high-level Petri nets, knowledge-based systems
Citation:
J. Lee, L.F. Lai, "A High-Level Petri Nets-Based Approach to Verifying Task Structures," IEEE Transactions on Knowledge and Data Engineering, vol. 14, no. 2, pp. 316-335, March-April 2002, doi:10.1109/69.991719
Usage of this product signifies your acceptance of the Terms of Use.