FULL TITLE

Quantifying the significance of consequences in human reliability design

KEYWORDS

Decision support, requirements specification, design rationale, human reliability, scenario based design

SUMMARY

Scenario based design allows for the early elicitation of requirements during the design phase of system development. Typically design involves an iterative process during which a specification or implementation more closely meets a realistic set of requirements. This set of realistic requirements also evolves with the design specification. Requirements will include the need to prevent the implemented system from leading to faults. Not all requirements are equal and deciding which requirements have priority is a matter for expert judgement. Some requirements may be considered essential to any redesign and others may have only minor consequences for the development [2].

We have explored how numbers can be used to highlight the impact of consequences identified by descriptive scenario analysis. In the context of a human reliability analysis (HRA) example, the results of a scenario-based design technique, called THEA [1] (Technique for Human Error Assessment), have been investigated to determine the impact of identified new requirements. THEA is a descriptive technique and the analysis of its results relies on the application of expert judgement.

HEART (Human Error Assessment and Reduction Technique) [3] is used as a means of assessing the reliability of subtasks within the scenario and is used to establish priorities as part of the justification process for redesign options.

Links

dependability cases, reuse

KEY REFERENCES

[1] Pocock S., Harrison M., Wright P. and Johnson P. (2001) THEA – A technique for human error assessment early in design. Human-Computer Interaction: INTERACT’01, Hirose M (Ed), pp. 247-254. IOS Press.

[2] Smith, S. P. and Harrison, M. D. (2002) Augmenting descriptive scenario analysis for improvements in human reliability design. In G. B. Lamont (ed), Applied Computing 2002: Proceedings of the 2002 ACM Symposium on Applied Computing, pp. 739-743, ACM.

[3] Williams J. C. (1986) HEART – a proposed method for assessing and reducing human error. 9th Advances in Reliability Technology Symposium. University of Bradford.

PAPERS

Smith, S. P. and Harrison, M. D. (2002a) Augmenting descriptive scenario analysis for improvements in human reliability design. Applied Computing 2002: Proceedings of the 2002 ACM Symposium on Applied Computing, G. B. Lamont (Ed), pp. 739-743, ACM.

Smith, S. P. and Harrison, M. D. (2002b) Blending descriptive and numeric analysis in human reliability design, Interactive Systems: Design, Specification and Verification, P. Forbrig, q. Limbourg, B. Urban and J. Vanderdonckt (Eds), Lecture Notes in Computer Science Volume 2545 pp. 223-237, Springer.

AUTHORS

Shamus Smith and Michael Harrison (Newcastle)