Chris W. Johnson

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The Intelligent Environment consists of ubiquitous connectivity in sensor rich environments coupled with adaptive technologies that allow access from multiple devices with varying capabilities. Context information is drawn from what the Intelligent Environment can sense about its current physical and computational environments. This context information(More)
This paper presents some ideas for efficiently allocating resources to enhance the performance of gang scheduling. We first introduce a job re-packing scheme. In this scheme we try to rearrange the order of job execution on their originally allocated processors in a scheduling round to combine small fragments of available processors from different time(More)
The message passing interface standard released in April 1994 by the MPI Forum 2], deenes a set of message passing primitives for multi-computers and clustered systems. The standard provides a large collection of functions, with the aim of providing eecient implementations, source code portability and support for the development of parallel libraries. In(More)
Clinicians and support staff are faced with increasingly complex computer applications. This complexity stems partly from the integration of heterogeneous systems ranging from computerized patient records to theatre management and dosage planning applications, and also from the increased functionality offered by the new generation of IT systems. Many(More)
We identify four roles that social networking plays in the 'attribution problem', which obscures whether or not cyber-attacks were state-sponsored. First, social networks motivate individuals to participate in Distributed Denial of Service attacks by providing malware and identifying potential targets. Second, attackers use an individual's social network to(More)
There appears to be a reasonably common understanding about plagiarism and collusion in essays and other assessment items written in prose text. However, most assessment items in computing are not based in prose. There are computer programs, databases, spreadsheets, and web designs, to name but a few. It is far from clear that the same sort of consensus(More)
This paper describes the results of an independent analysis of the primary and contributory causes of aviation accidents in Canada between 1996 and 2003. The purpose of the study was to assess the comparative frequency of a range of causal factors in the reporting of these adverse events. Our results suggest that the majority of these high consequence(More)
National and international organisations including NIST and ENISA have published guidance that is intended to help organisations respond to, and recover from, cyber incidents. They provide detailed information about contingency planning, about the processes needed to gather and analyse evidence, about appropriate ways to disseminate the findings from(More)
This paper describes the results of an independent analysis of the probable and contributory causes of selected aviation accidents in the United States between 1996 and 2003. The purpose of the study was to assess the comparative frequency of a variety of causal factors in the reporting of these adverse events. Although our results show that more of these(More)