Three Patent applications filed with the USPT office:

  • Title: “Threat-Specific Security Risk Evaluation for Networked Systems,” (US Patent), Filed on 01/05/2019, No.: 16/400,514.
  • Title: “Temporal-Hierarchical Attack Representation Model (T-HARM): A graphical security model to capture dynamic network changes,” (US Patent), Filed on: 06/12/2018. Patent application No.: 16/211,762
  • Title: “Method and System for Adaptive Security in Cloud-based Services,” (US Patent), Filed on 17/10/2017. U.S. Patent Publication No: US-2018-0114015-A1. US Patent App. 15/785,858.

Four Books:

  1. Khan, K.: Developing and Evaluating Security-Aware Software Systems. Information Science Reference, PA, USA, ISBN-10: 1466624825, ISBN-13: 978-1466624825, Total pages 422, 2013.
  2. Khan, K.: Security-Aware Systems Applications and Software Development Methods, Informa- tion Science Reference, PA, USA, ISBN 978-1-4666-1580-9, ISBN 978-1-4666-1581-6 (ebook), ISBN 978-1-4666-1582-3, 2012, Total pages 416.
  3. Khan, K.: Managing Web Services Quality: Measuring Outcome and Effectiveness. (edited book). Information Science Reference, PA, USA, October 2008. ISBN-10: 1605660426, ISBN- 13: 978-1605660424. Total pages 318.
  4. Khan, K., Zhang, Y.: Managing Corporate Information Systems Evolution and Maintenance. (edited book) 2005, ISBN: 1-59140-367-7, Total pages 376.

Papers in refereed journals/magazines/books :

  1. Zolanvari, M., Teixeira, M., Gupta, L., Khan, K., Jain, R., “Machine Learning-based Network VulnerabilityAnalysis of Industrial Internet of Things,” IEEE Internet of Things, accepted, 2019. (IF 9.51 in 2020)
  2. Hong, J., Nhlabatsi, A., Kim, D., Fernandez, R., Fetais, N., Khan, K., “Systematic Identification of Threats in the Cloud: A Survey,” J. of Computer Networks, Elsevier, Vol. 150, February, 2019. pp. 46-69. (IF 3.03 in 2020).
  3. Wang, Y., Khan, K., “Matrix Barcode Based Secure Authentication without Trusting Third 
Party,”  IEEE IT Professional, Vol. 21(3), 2019. (IF 1.618 in 2019)
  4. Nhlabatsi, A., Hong, J., Kim, D.,  Fernandez, R., Hussein, A., Fetais, N., Khan, K., “Threat-specific Security Risk Evaluation in the Cloud”, accepted, Oct. 2018, IEEE Transactions on Cloud Computing (IF 7.92 in 2019).
  5. Hong, J., Enoch, S., Nhlabatsi, A., Kim, D., Fetais, N., Khan, K., “Dynamic Security Metrics for Measuring the Effectiveness of Moving Target Defense,” , Journal of Computers & Security, Elsevier, Vol 79: 33-52, 2018 (IF 3.06 in 2020).
  6. Hu, Jinwei, Khan, K., Zhang, Y., Bai, Y., Li, R, “Role Updating in Information Systems using Model Checking”, Journal of Knowledge and Information Systems, Springer,  Vol. 51(1), 2017, pp. 187-234. (IF 2.39 in 2018).
  7. Asuncion, V., Khan, K., Alhazbi, S., Erradi, A., “Reasoning About Policies in Security-Aware Service,” International Journal of Cooperative Information Systems,   Vol. 25 (1): 1650003, 2016, (IF 1.00)
  8. Wang, Y., Malluhi, Q., Khan, K., “Garbled Computation in Cloud”, Future Generation Computer Systems, Elsevier, 62: 54-65, 2016 (IF 4.63).
  9. Nhlabatsi, A., Tun, T., Khan, N., Yu, Y., Bandara, A., Khan, K., Nuseibeh, B., “Why Can’t I do that?: Tracing Adaptive Security Decision”, EAI Endorsed Transaction on Self-Adaptive Systems, European Alliance for Innovation, Vol. 1(1), 2015, pp.1-16.
  10. Khan, K., Malluhi, Q., “Trust in Cloud Services: Providing more Control to Clients”, IEEE Computer, vol. 46(7):94-96, July 2013, pp.94-96 (IF 1.94)
  11. Khan, K., Malluhi, Q. “Role of Contextual Properties in Enterprise Service Migration to Cloud”, Journal of Concurrency and Computation: Practice and Experience, Wiley & Sons, 2013, Vol. 25:2455-2470. (IF 1.16)
  12. Khan, K., Erradi, A., Alhazbi, S., Han, J.,“Addressing Security Compatibility for Multi-Tenant Cloud Services”, IJCAT, 47(4): 370-378 (2013)
  13. Khan, K., Malluhi, Q., “Privacy and Confidentiality in Cloud Computing”, a book chapter, Chapter 14 in Scalable Computing and Communications: Theory and Practice, (S. Khan, L. Wang, and A. Zomaya, Eds.), Wiley, New Jersey, 2012, pp. 277-288.
  14. Khan, K., “State of Sharing Clinical Information in a Healthcare System in the Gulf”, International Journal of Reliable and Quality E-Healthcare, Vol.1(3), 2012, pp. 27-42.
  15. Bai, Y., Khan, K., “Secure Information System Using Modal Logic Technique”, International Journal of Secure Software Engineering, Vol. 2(2), April-June, 2011, pp. 65-76.
  16. Khan, K., Malluhi, Q., “Establishing Trust in Cloud Computing”, IEEE IT Professional, September/October, Vol. 12(5), 2010. (IF 1.61)
  17. Khan, K., et al., “Assessing User-Centric Quality of Web-Based Systems”, International Journal of Software Engineering, Vol. 3 (1):3-28, January 2010.
  18. Khan, K., Han, J., “Tool Support for for Secure Software Integration”, International Journal of Secure Software Engineering, April-June 2010, pp. 36-56
  19. Khan, K., Gangavarapu, N., “Addressing Cloud Computing in Enterprise Architecture”, Cutter IT Journal, Cutter Consortium, MA, Vol. 22(11), November 2009, pp. 27-33.
  20. Khan, K., “Security Dynamics in Cloud Computing”, Cutter IT Journal, MA, Vol 22(6/7), June/July 2009, pp. 38-43.
  21. Khan, K. with Samaka, M., “Wireless Networks”, a book chapter, In Wiley Encyclopedia of Computer Science and Engineering, edited by Benjamin Wah, 2009, Wiley and Sons, USA, ISBN: 978-0471383932
  22. Khan, K., “A Decision Support System for Selecting Secure Web Services”, A book chapter in the Encyclopedia of Decision Making and Decision Support Technologies, edited by Adam & Humphreys, Information Science Reference, PA, USA, 2008, pp. 211-217
  23. Khan, K., “Security-Aware Service Specification for Healthcare Information Systems”, A book chapter, Encyclopedia of Healthcare Systems, Edited by Wickramasinghe & Geisler, Information Science Reference, PA, USA, 2008, pp.1236-1240.
  24. Khan, K., “Revisiting Timed Open Book Assessment”, The Educational Reform Journal, 5th Edition, Qatar University, pp. 5-7, 2007.
  25. Khan, K., Kapurubandara, M., Chadha, U., “Incorporating Business Requirements and Con- straints in Database Conceptual Model”, Australian Computer Science Communications, Australian Computer Society, 26(6):59-64, 2004.
  26. Khan, K.,“Integrating Security Properties with Systems Design Artefacts”, a chapter in Con- structing the Infrastructure for the Knowledge Economy: Methods and Tools, Theory and Prac- tice, edited by H. Linger et al., Kluwer Academic/Plenum Publishers, 2004, pp. 367-377.
  27. Khan, K., Han, J., “Composing Security-Aware Software”, IEEE Software, 19(1):34-41, 2002. (IF 2.04)
  28. Chapin, N., Hale, J., Khan, K., et al., “Types of Software Maintenance and Evolution”, European Journal of Software Maintenance and Evolution: Research and Practice, John Wiley and Sons, 13(1):3-29, 2001. (IF 1.4)
  29. Khan, K., Lo, B., Skramstad, T., “Tasks and Methods for Software Maintenance: A Process Oriented Framework”, Australian Journal of Information Systems, 9(1):51-60, September 2001.
  30. Rahim, M., Khan, K., Selamat, M., “Adoption versus Abandonment of CASE Tools: Lessons from Two Organisations”, Journal of Information Technology and People, special issue, MCB University press , UK, 10(4):316-329, 1997. (Invited paper).
  31. Khan, K., Rashid, M., Lo, B., “A Task-Oriented Software Maintenance Model”, Malaysian Journal of Computer Science, 9(2):36-42, December, 1996. (IF 0.6)
  32. Khan, K. ,Skramstad, T., “Data Structures for Extracting and Preserving Low-Level Program Information”, Malaysian Journal of Computer Science, 8(2):66-79, December 1995. (IF 0.6)

Conference proceedings 

  1. Enoch, S., Hong, J., Ge, M., Khan, K., Kim, D., “Multi-Objective Security Hardening Op- timisation for Dynamic Networks,” IEEE International Conference on Communication (ICC), Shanghai, 22-24 May, 2019.
  2. An, S., Eom, T., Park, J., Hong, J., Nhlabatsi, A., Fetais, N., Khan, K.,  Kim, D. “CloudSafe: A Tool for an Automated Security Analysis for Cloud Computing,” IEEE TrustCom, New Zealand, (2019)
  3. Khan, K., Shaheen, M., Wang, Y., “Using Sparse Matrices to Prevent Information Leakage in Cloud Computing,” IEEE 6th International Conference on Future Internet of Things and Cloud (FiCloud), Barcelona, 2018.
  4. Nhlabatsi, A., et al., Khan, K., “A Threat-Specific Security Risk Assessment Framework for the Cloud,” 18th IEEE International Conference on Software Quality, Reliability, and Security (QRS 2018), Lisbon.
  5. Hong, J., Yusuf, S., Kim, D., Khan, K.,”Stateless Security Risk Assessment for Dynamic Networks,”  IEEE/IFIP International Conference on Dependable Systems and Networks, June 2018, Luxemburg.
  6. Tun, T., Yang, M., Bandara, A., Yu, Y., Nhlabatsi, A., Khan, K., Nuseibeh, B., “Requirements and Specifications for Adaptive Security: Concepts and Analysis,” ACM/IEEE International Symposium on Software Engineering for Adaptive and Self-Managing Systems (SEAMS), Gottenburg, Sweden, May 28-29, 2018.
  7. Khan, K., Jiang, Z., “Managing Client-Specific Customised Functions in Multi-tenant Software-as-a-Service,” IEEE Proceedings of the Int’l Conference on Software Quality, Reliability, and Security, Prague, 2017, pp. 108-113.
  8. Khan, K., Nhlabatsi, A., “Identifying Common Behavioural Traits of Lone-Wolves in Recent Terrorist Attacks in Europe,” 19th International Conference on Counter Terrorism and Human Security, Zurich, 27–28, 2017,  Vol. 11(7), pp. 1710-1713.
  9. Khan, K., Nhlabatsi, A., Khan, N., “A Process Model for Customization of Software in Multi- Tenant SaaS Model,” ACM/IEEE Conference on Utility and Cloud Computing, Cyprus, December 2015.
  10. Khan, K., Shaheen, M., “Data Obfuscation for Privacy and Confidentiality in Cloud Computing,” IEEE Proc. of the Int’l Conference on Quality, Reliability and Security, Vancouver, 2015.
  11. Nhlabatsi, A., Yu, Y., Zisman, A., Tun, T., Khan, N., Bandara, A., Khan, K., Nuseibeh, B., “Managing security control assumptions using causal traceability,” IEEE Proc. of the Sym. on Software and Systems Traceability, 2015, pp. 43-49.
  12. Ryu, S, Erradi, A., Khan, K., Alhazbi, S., Benatallah, B., “Message Content-Aware Evolution of Trust Negotiation Protocols in Cloud Collaboration”, accepted, ICSOC, 2014, Paris.
  13. Khan, K., Shaheen, M., “Empowering Users of Cloud Computing on Data Confidentiality,” IEEE CloudNet, Luxemburg, October, 2014, pp. 272-274.
  14. Asuncion, V., Khan, K., Erradi, A., Alhazbi, S., “Reasoning about Security Policies of Services using Answer Set Programming”, IEEE SCC, 2014, Alaska.
  15. Nhlabatsi, A., Tun, T., Khan, N., Yu, Y., Bandra, A., Khan, K., Nuseibeh, B., “Traceability for Adaptive Information Security in the Cloud”, IEEE Cloud, 2014, Alaska.
  16. Khan, K., Shaheen, M., “Secure Cloud Services: Matrix multiplication revisited”, 16th IEEE Conf. on Computational Science and Engineering, Sydney, Dec., 2013, pp. 9-14.
  17. Caprin, E., Zhang, Y., Khan, K., “Social Access Control Language (SocACL)”, ACM proceedings of the 6th International Conference on Security of Information and Networks (SIN), Aksaray, Turkey, pp. 261-265, Nov. 26-28, 2013.
  18. Khan, K., Bai, Y., “Client-Enabled Automatic Verification of Health Regulatory Compliance in Cloud Computing”, Proceedings of the IEEE HealthCom’13, Lisbon, October 9-12, 2013.
  19. Bai, Y., Khan, K., “Program Completion as Constraint Satisfaction: Tight Logic Programs Revisited”, Proc. of the 2013 International Conference on Artificial Intelligence, July 22-25, Las Vegas, pp. 274–280
  20. Alhazbi, S., Khan, Khaled, Erradi, A., “Preference based Semantic Matching of Web Service Security Policies”, Proceedings of the IEEE ICEEE’2013, Sousse, June 2013.
  21. Hu, J., Khan, K., Bai, Y., Zhang, Y., “Compliance Checking for Usage-Constrained Credentials in Trust Negotiation Systems”, Information Security Conference (ISC 2012), Passau, Germany, Sept 19-21, 2012.
  22. Hu, J., Khan, K., Bai, Y., Zhang, Y., “Constraint-Enhanced Role Engineering via Answer Set Programming”, ACM proceedings of the ASIACCS 12, May 24, 2012, Seoul, Korea
  23. Hu, J., Khan, K., Zhang, Y., “Tracking and Constraining Authorization Provenance”, 25th IEA/AIE 2012, Dalian, June 9-12, 2012, Springer Proceedings Lecture Notes in Computer Science, Vol. 7345, pp. 669-678
  24. Khan, K., Erradi, A., Alhazbi, S., Han, J.,“Modeling Security Importance and Preferences of Software Services”, 3rd IEEE International Conference on Software Engineering and Service Science (ICSESS), Beijing, June 2012, pp. 300-303.
  25. Malluhi, Q., Khan, K., “ Cloud Computing without Seeing”, ACM Proceedings of the First International Workshop on Security and Privacy Preserving in e-Societies(SeceS ’11), 2011, pp 42-44
  26. Khan, K., Erradi, A., Alhazbi, S., Han, J., “Security Oriented Service Composition:A Frame- work” , 8th International Conference on Innovations in Information Technology (Innovations’12), UAE, March 2012, pp. 48-53.
  27. Bai, Y., Khan, K., “A Modal Logic For Information System Security”, Proceedings of the Australian Information Security Conference, Perth, 2011.
  28. Khan, K., Malluhi, Q., “Identifying Contextual Properties of Software Architecture in Cloud Computing”, Proceedings of the 9th IEEE International Conference on Dependable, Autonomic and Secure Computing, December 12-14, 2011, Sydney, IEEE Computer Society Press, Los Alamitos, Calif., pp. 561-568.
  29. Khan, K., “Profile Based Security Assurances for Service Software”, Springer Lecture Notes in Business Information Processing, Vol. 82, 2011.
  30. Khan, K., Malluhi, Q., “Security-Aware Service Composition for End users of Small Enter- prises”, 9th International Conference on Software Methodologies, Tools, and Techniques (SOMeT), Japan, September 2010, pp. 257-267.
  31. Khan, K. with Jiang, Z., Guo, X. and Gangavarapu, N., “Knowledge-based Algorithms to Optimise e-Learning Outcome”, Proceedings of the 2009 International Conference on Frontiers in Education: Computer Science and Computer Engineering, Las Vegas, Nevada, USA (July 13-16, 2009)
  32. Khan, K., Han, J., “Specifying Security Goals of Component Based Systems : An End-User Perspective”, Proceedings of the 7th IEEE International Conference on Composition-Based Soft- ware Systems, Madrid, February 2008, IEEE Computer Society Press, Los Alamitos, Calif., pp. 101-109.
  33. Khan, K., Tan, C., “SecCom: A Prototype for Integrating Security-Aware Components”, Springer Lecture Notes on Business Information Processing, 2009, pp. 393-404.
  34. Khan, K., “Assessing Quality of Web Based Systems”, Proceedings of the 6th ACS/IEEE Inter- national Conference on Computer Systems and Applications (AICCSA-08), Doha, April 2008
  35. Khan, K., “Selecting Web Services with Security Assurances: A managerial perspective”, Pro- ceedings of 11th Pacific Asia Conference on Information Systems (PACIS), New Zealand, July 2007
  36. Goerge, D., Khan, K.,“Prioritizing and Partitioning of Business Requirements for Incremental Web Development”, Proc. IMB 2006, Sydney February 14-17, 2006.
  37. Han, J., Kowalczyk, R., Khan, K., “Security Oriented Service Composition and Evolution”, IEEE Asia Pacific Software Engineering Conference, Banglore, December, 2006,IEEE Computer Society Press, Los Alamitos, Calif. pp 71-78.
  38. Khan, K., Han, J., “Assessing Security Properties of Software Components: A Software Engi- neer’s Perspective”, Proceedings of the Conference on Australian Software Engineering Confer- ence, Sydney, 18-20 April 2006, IEEE Computer Society, Los Alamitos, Calif., pp. 199-210
  39. Khan, K., Han, J. “Deriving Systems Level Security Properties of Component Based Compos- ite Systems”, Proceedings of the Conference on Australian Software Engineering Conference, Brisbane, IEEE Computer Society Press, Los Alamitos, Calif., 29 March – 1 April 2005, pp. 334-343.
  40. Khan, K., Han, J., “A Process Framework for Characterising Security properties of Component- Based Software Systems”, IEEE Australian Software Engineering Conference, IEEE Computer Society, Los Alamitos, Calf., 2004, pp. 358-367.
  41. Khan, K., Han, J., “A Security Characterisation Framework for Trustworthy Component Based Software Systems”, Proc. IEEE COMPSAC 2003, Dallas, November 2003, IEEE Computer Society, Los Alamitos, Calf., pp. 164-169.
  42. Khan, K., Han, J., Zheng, Y., “A Framework for an Active Interface to Characterise Compo- sitional Security Contracts of Software Components”, Australian Software Engineering Confer- ence, Canberra, IEEE Computer Society Press, Los Alamitos, Calf., 2001, pp. 117-126.
  43. Khan, K.,Han, J., Zheng, Y., “Security Characterisation of Software Components and Their Composition”, 36th International Conference on Technology of Object-Oriented Languages and Systems (TOOLS’00), IEEE Computer Society Press, Los Alamitos, Calf., 2000, China, pp. 240-249.
  44. Khan, K., Han, J., Zheng, Y., “Characterising User Data Protection of Software Components”, Proceedings Australian Software Engineering Conference (ASWEC’00), 2000 Canberra, Aus- tralia, IEEE Computer Society press, Los Alamitos, Calf., 2000, pp. 3-11
  45. Eenoo, C., Hylooz, O., Khan, K.,“Addressing Non-Functional Properties in Software Architec- ture using ADL”, Proc. of the 6th Australasian Workshop on Software and System Architectures, Brisbane, Australia, March 29 2005, pp. 6-12.
  46. Khan, K., Gangavarapu, N., “Evolution of Security Properties – a must”, Proc. International Conference on Software Engineering and Research, published by CSREA (Computer Science Research Education and Application) Press, Las Vegas, 2004.
  47. Tran, T., Khan, K., Lan, Y., “A Framework for Transforming Artefacts from Data Flow Dia- grams to UML”, IASTED International Conference on Software Engineering, Innsbruck, Austria, 18-22 February 2004, pp. 123-128
  48. Lilburne, B., Devkota, P., Khan, K., “Measuring Quality Metrics for Web Applications”, 2004 IRMA International Conference, Idea Group Inc., , New Orleans, May 23-26 2004.
  49. Khan, K. “Integrating Security Properties with Systems Design Artefacts”, Proc. International Conference on Information Systems Development, Melbourne, 2003.
  50. Khan, K., Lan, Y., “Recreating Design Artefacts of Information Systems for System Evolution and Maintenance”, 2003 International IRMA Conference, Philadelphia, May, 2003, pp. 843-845.
  51. Lan, Y., Khan, K., “Measuring the Readiness of Globalisation: a metrics based approach”, 2003 International IRMA Conference, Philadelphia, May 2003, pp. 723-726.
  52. Khan, K., “Identifying Ilities at the Software Architectural Level”, International Conference on Software Engineering and Research, , Las Vegas, 2002.
  53. Khan, K., Han, J., Zheng, Y., “Specifying Security Requirements and Assurances of Software Components”, 5th Australian Workshop on Requirements Engineering, , Brisbane, December 8-9, 2000.
  54. Khan, K., Han, J., Zheng, Y., “A Scenario Based Security Characterisation of Software Compo- nents”, 3rd Australian Workshop on Software Architectures, Sydney, Sponsored by IEEE NSW Computer Society chapter, Nov. 19-20, 2000, pp. 55-64
  55. Khan, K., Lo, B., et al.,“Software Maintenance Process: Tasks and Methods”, 11th Australasian Conference on Information Systems (ACIS), Brisbane, Dec. 6-8, 2000.
  56. Khan, K., Skramstad, T., “Software Clinic: A Different View of Software Maintenance”, Inter- national Conference on Information Systems Analysis and Synthesis (ISAS 2000), International Institute of Informatics and Systemics, Co-sponsored by IEEE Computer Society-Latin America, Orlando, Florida, July 23-36 2000, pp. 508-513.
  57. Skramstad, T., Khan, K., Rashid, M., “Constructing Commercial Off-the- Shelf from Legacy System: A Conceptual Framework”, Australasia Conference on Information Systems (ACIS), Wellington, 1-3 December 1999, Australian Computer Society press, pp. 798-805.
  58. Khan, S, Khan, K., Sarkar, N., “The State of Library Automation and Resource Sharing: A Developing Country Perspective”, Proc. 9th Int’l Conference of Information Resources Manage- ment Association, Idea Group Publishing, Boston, May, 1998.
  59. Khan, K., Ramakrishnan, M., Lo, B.,“Assessment of Software Maintenance Tools: A Concep- tual Framework”, Proc. Pacific Asia Conference on Information Systems (PACIS’97), QUT, Brisbane, 1997, pp. 527-536.
  60. Rashid, M., Rahim, M., Khan, K., et al., “Computer Science and Information Technology in Brunei Darussalam: Trends, Options and the Challenges”, PURIH, A book published in conjunction with the 10th Anniversary of University of Brunei Darussalam Establishment, UBD Press, 1996, pp. 270-284.
  61. Khan, K., “A Generic Model for Software Maintenance”, Proc. Int’l Conf. on Mathematical Modelling, University of Brunei Darussalam, UBD Press, 1995, pp. 263-266.
  62. Selamat, M., Khan, K., Rahim, M., “A Comparative Study of a System Built with SDLC and Prototyping Approaches: Function Points Perspective”, Proc. 6th International Conference of Information Resources Management Association, Idea Group Publishing, Atlanta, 1995, pp. 145-149.
  63. Rahim, M., Selamat, M.,Khan, K., “Success and Failure in CASE Tools Adaption: A Tale of Two Organisations”, Proc. Pan Pacific Conference on Information Systems(PACIS), Singapore 1995, pp. 182-190.
  64. Rashid, M., Khan, K., Ghani, A., “Simulation of a Local Area Computer Network Access Scheme for Packet Voice Communication Based on An Approximate Delay Equation”, Conference on Pure and Applied Mathematics, Bahrain, 1995. IEEE Computer Society, Los Alamitos, Calif., pp. 334-343.
  65. Khan, K., Han, J., Zheng, Y.,“Security Properties of Software Components”, Proceedings 1999 International Information Security Workshop, Springer Lecture Notes in Computer Science, Vol. 1729, 1999, pp. 52-56.
  66. Skramstad, T., Khan, K.,“Assessment of Reverse Engineering Tools: A MECCA Approach”, Proc. Symposium on Assessment of Software Development Tools, Louisiana, IEEE Computer Society Press, Los Alamitos, Calif., 1992, pp. 120-126.
  67. Skramstad, T., Khan, K.,“A Redefined Software Life Cycle Mode for Improved Maintenance”, Proc. Conf. on Software Maintenance, Florida, IEEE Computer Society Press, Los Alamitos, Calif., 1992, pp. 193-197.