Abstract
This paper presents work aimed at supporting the design of temporal aspects of socio-technical systems. Time Design is a framework for (a) analysing and representing temporal properties of the work domain, (b) generating design options that support timely, flexible and dependable function servicing, and (c) providing knowledge about the characteristics and biases of human temporal control behaviour. In support of the latter end, two microworld experiments that investigated temporal control decisions in a supervisory control task are presented. These experiments manipulated event rate, the duration of event rate blocks, the availability of online and offline event rate information, and the accuracy of this information. The studies identified conditions where attention to temporal information decreased and the use of conservative temporal control strategies increased. © 2004 IEEE.

Abstract
In this paper we consider the performance of different scheduling policies in a smart environment. Models are generated under a hospital scenario, and are used to simulate patient flow under three scheduling policies. SimJava 2.0 is adopted as the main simulator in this work. The findings generally show that the dynamic scheduling policy has better performance than the static scheduling policy. © 2011 IEEE.

Abstract
Hazard analysis for safety-critical systems require sufficient coverage and rigour to instill confidence that the majority of hazardous consequences have been identified. These requirements are commonly met through the use of exhaustive hazard analysis techniques. However, such techniques are time consuming and error-prone. As an attempt at exhaustive coverage, hazard analysts typically employ reuse mechanisms such as copy-and-paste. Unfortunately, if reuse is applied inappropriately there is a risk that the reuse is at the cost of rigour in the analysis. This potential risk to the validity of the analysis is dependent on the nature and amount of reuse applied. This paper investigates hazard analysis reuse over two case studies. Initially reuse in an existing safety argument is described. Argument structures within the hazard analysis are identified and the amount of verbatim reuse examined. A second study is concerned with how reuse changes as a result of tool support. In contrast to the first case, the defined arguments are more diverse - reuse has occurred but is less verbatim in nature. Although tool support has aided the customisation of the reused arguments, many are only trivially customised. An edit distance algorithm is utilised to identify and enumerate verbatim and trivial reuse in the arguments.

Abstract
The cost of deploying a ubiquitous system to enhance a physical environment is likely to be considerable. The success of its deployment is highly dependent on its context: the physical environment and the activities that are to be carried out within it. This paper provides an initial exploration of whether stochastic process algebras (in particular PEPA with a Fluid Flow semantics) might be used to explore consequences before deployment. The focus of the exploration is to aid understanding of how a proposed system supports users within the environment. The challenge is to provide notations and techniques that will enable the analysis of potentially complex systems.

Abstract
However sophisticated a development environment may be it is inevitable that some diagnosis takes place in the target system. When the target consists of a number of processors co-operating in a complex way diagnosis can be extremely difficult to achieve. This paper describes techniques for monitoring behaviour in a target system so that there is minimal disturbance. The information collected can be used subsequently to simulate the run in the host where the full set of debugging tools can be used. These techniques are being used as guidelines in a research project funded under the UK Alvey initiative. © 1985.

Abstract
Accidents at Flixborough, Seveso, Bhopal, Three Mile Island, Windscale and Chernobyl have led to increasing concern over the safety and reliability of control systems. Human factors specialists have responded to this concern and have proposed a number of techniques which support the operator of such applications. Unfortunately, this work has not been accompanied by the provision of adequate tools which might enable a designer to carry it beyond the "laboratory bench" and on to the "shop floor". The following paper exploits formal, mathematically based specification techniques to provide such a tool. Previous weaknesses of abstract specifications are identified and resolved. In particular, they have failed to capture the temporal properties which human factors specialists identify as crucial to the success or failure of interactive control systems. They also provide the non-formalist with an extremely poor impression of what it would be to like to interact with potential implementations. Temporal logic avoids these deficiencies. It can make explicit the sequential information which may be implicit within a design. Executable subsets of this formalization support prototyping and this provides a means of assessing the qualitative "look and feel" of potential implementations. A variety of presentation strategies, including structural decomposition and dialogue cycles, have been specified and incorporated directly into prototypes using temporal logic. Prelog, a tool for the Presentation and REndering of LOGic specifications, has been developed and its implementation is described. © 1992.