Steven Bradley

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Existing formal methods for real-time largely deal with abstract models of real-time systems, and seldom address implementation issues; they are mainly used for modelling and speciication. In this paper we propose an alternative approach, in which a new timed process algebra, AORTA, is used as a design language, which can be veriiably implemented. As well(More)
In order to demonstrably satisfy hard real-time deadlines, a system must be predictable, and in particular the kernel must be predictable. In this paper we present and analyse a predictable kernel related to AORTA, a formal design language for hard real-time systems. The features of the kernel allow AORTA designs to be veriiably and semi-automatically(More)
AORTA is an implementable timed process algebra which has been proposed as a design language for hard real-time systems. In this paper we show how AORTA can be used to design and model timed protocols, illustrated by the alternating bit protocol. We also describe tools which have been developed for simulation, veriication and automatic implementation of(More)
Embedded control systems appear in many of the manufactured products upon which our society increasingly depends. System developers need better development methods in order to be more confident that the systems which they deliver will behave properly. The need is particularly pressing in the case of distributed, hard real-time control systems for which(More)
This paper tackles the problem of using formal methods for practical real-time system development and ver-iication, and is based on a real example. Many formal methods for real-time systems have been proposed, but this technique (AORTA) is one of the few to address the issue of how formal designs are to be implemented. Earlier papers on AORTA have been(More)
BACKGROUND In anticipation of applying Appropriate Use Criteria for percutaneous coronary intervention (PCI) quality improvement, we determined the prevalence of appropriate, uncertain, and inappropriate PCIs stratified by indication for all PCIs performed in the state of Washington. METHODS AND RESULTS Within the Clinical Outcomes Assessment Program, we(More)
BACKGROUND Substantial geographic variation exists in percutaneous coronary intervention (PCI) use across the United States. It is unclear the extent to which high PCI utilization can be explained by PCI for inappropriate indications. The objective of this study was to examine the relationship between PCI rates across regional healthcare markets utilizing(More)
A n ideal healthcare system aims to provide care that is safe, effective, efficient, equitable, timely and patient-centered. 1 Translation of these aims into practice for patients suffering from ST-elevation myocardial infarction (STEMI) could result in an ideal primary percutaneous coronary intervention (PCI) system of care. In this ideal PCI system of(More)