Faster simulation plots

Most simulation plots are heavily oversampled. Ignoring unnecessary data points dramatically reduces plot time with imperceptible effect on quality. The technique is suited to most plot devices. The departments laser printer's speed was tripled for large simulation plots by data thinning. This reduced printer delays without the expense of a faster laser printer. Surpisingly, it saved computer time as well. All plot data are now thinned, including PostScript and terminal plots. The problem, solution, and conclusions are described. The thinning algorithm is described and performance studies are presented. To obtain FORTRAN 77 or C source listings, mail a SASE to the author

Reviews

Steve McDowell and Phil Race, 500 Computing Tips for Trainers, London: Kogan Page, ISBN: 0–7494–2675–6. Paperback, 160 pages, £15.99

Reviews

Alan Clarke, Designing Computer‐Based Learning Materials, Aldershot: Gower, 2001. ISBN: 0–566–08320–5. Hardback, xviii+196 pages, £45.00

Analysis of requirements volatility during software development life cycle

Investigating the factors that drive requirements change is an important prerequisite for understanding the nature of requirements volatility. This increased understanding will improve the process of requirements change management. This paper mainly focuses on change analysis to identify and characterize the causes of requirements volatility. We apply a causal analysis method on change request data to develop a taxonomy of change. This taxonomy allows us to identify and trace the problems, reasons and sources of changes. Adopting an industrial case study approach, our findings reveal that the main causes of requirements volatility were changes in customer needs (or market demands), developers' increased understanding of the products, and changes in the organization policy. During the development process, we also examined the extent of requirements volatility and discovered that the rate of volatility was high at the time of requirements specification completion and while functional specification reviews were conducted

Reviews

Judith Jeffcoate, Multimedia in Practice ‐Technology and Applications, BCS Practitioner Series, Prentice‐Hall International, 1995. ISBN: 0–13–123324–6. £24.95

Cluster randomisation or randomised consent as an appropriate methodology for trials in palliative care: a feasibility study [ISRCTN60243484]

BACKGROUND: Although guidelines for the care of the dying patient exist the evidence base to support the guidelines is poor. Some of the factors contributing to this include failure to recruit to trials, protective healthcare professionals and subsequent attrition from trials due to the death of the patients. Recent studies report favourably on the use of cluster randomisation as an appropriate methodology for use in this patient group. METHODS/DESIGN: A feasibility study, exploring two types of randomisation as appropriate methodology for trials involving dying patients. Cluster randomisation and randomised consent will be utilised following a crossover design at two sites, one oncology ward and one Macmillan unit within the Northwest Wales NHS Trust. All patients commencing on the Integrated Care Pathway (ICP) for the Last Days of Life will be eligible for inclusion in the study. Using the hypothesis that it is not necessary to prescribe an anti-emetic medication when setting up a syringe driver for the dying patient, the study will evaluate different models of research methodology. DISCUSSION: The identification of the most appropriate methodology for use in studies concerning this patient group will inform the development of future clinical studies. Furthermore, the outcomes of this feasibility study will inform the development, of a proposal seeking funding for Wales-wide trials in palliative care. The identification of an appropriate methodology will provide a starting point for the establishment of a robust evidence base for the care of the dying patient