Abstract: Large socio-technical systems impose a number of significant challenges, both technical and organisational. Their complexity makes all stages of their development (requirements analysis, specification, design, implementation, deployment and maintenance/evolution) subject to failure and costly re-working. Even the production of an unambiguous behavioural description of an existing system is far from straightforward. One characteristic of these computer-based systems is that they are required to function at many different time scales (from microseconds or less to hours or more). Time is clearly a crucial notion in the specification (or behavioural description) of dependable computer-based systems, but it is usually represented, in modeling schemes for example, as a single flat physical phenomenon. Such an abstraction fails to support the structural properties of the system, forces different temporal notions onto the same flat description, and fails to support the separation of concerns that the different time scales of the system facilitate. In this talk a framework involving the use of time bands will be introduced and elements of a time band model will be described.

Short Bio: Professor Alan Burns is Head of the Department of Computer Science, University of York, U.K. His research interests cover a number of aspects of real-time systems including the assessment of languages for use in the real-time domain, distributed operating systems, the formal specification of scheduling algorithms and implementation strategies, and the design of dependable user interfaces to real-time applications. Professor Burns has authored/co-authored over 370 papers/reports (http://www-users.cs.york.ac.uk/~burns/papers.html) and 10 books. Many of these are in the real-time area. His teaching activities include courses in Operating Systems and Real-time Systems.