Charles Crichton

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This paper defines a formal semantics for a subset of the Unified Modeling Language (UML). It shows how suitable combinations of class, object, state, and sequence diagrams can be associated with patterns of interaction, expressed in the event notation of Communicating Sequential Processes (CSP). The diagram semantics is then extended to give a meaning to(More)
1. An enzyme from Escherichia coli 9723 that reduces adenosine 3'-phosphate 5'-sulphatophosphate to inorganic sulphite is described. Extracts of E. coli K(12) and Bacillus subtilis 1379 contain a similar enzyme. 2. This reductase and sulphite reductase (EC 1.8.1.2) of E. coli 9723, E. coli K(12) and of B. subtilis are repressed by growth in the presence of(More)
The CancerGrid approach to clinical trials information systems is based on a metamodel developed from the CONSORT statement of best practice in reporting randomised controlled trials. The metamodel is instantiated with metadata elements drawn from a repository, to create a model of a particular clinical trial. The model is then used to derive automatically(More)
In molecular profiling studies of cancer patients, experimental and clinical data are combined in order to understand the clinical heterogeneity of the disease: clinical information for each subject needs to be linked to tumour samples, macromolecules extracted, and experimental results. This may involve the integration of clinical data sets from several(More)
The CancerGrid approach to software support for clinical trials is based on two principles: careful curation of semantic metadata about clinical observations, to enable subsequent data integration, and model-driven generation of trialspecific software artifacts from a trial protocol, to streamline the software development process. This paper explains the(More)
BACKGROUND The control of Clostridium difficile infections is an international clinical challenge. The incidence of C difficile in England declined by roughly 80% after 2006, following the implementation of national control policies; we tested two hypotheses to investigate their role in this decline. First, if C difficile infection declines in England were(More)
Effective data sharing, across government agencies and other organisations, relies upon agreed meanings and representations. A key, technological challenge in electronic governance is to ensure that the meaning of data items is accurately recorded, and accessible in an economical---effectively, automatic---fashion. In response, a variety of data and(More)
This paper introduces an approach to software development in which a series of working implementations are generated automatically from a series of formal specifications. The implementations are data stores, communicating through standard protocols. The specifications are precise object models, in which operations are described in terms of preand(More)
This paper explains how object models written in the Unified Modeling Language (UML) can be translated into formal, behavioural descriptions and used as a basis for automatic test generation. The behavioural descriptions are written in a language of communicating state machines: the Intermediate Format (IF). The translation from UML to IF is based upon an(More)