Erosion of the cortical plate overlying the sigmoid sinus is the most sensitive and specific CT finding for distinguishing coalescent from noncoalescent acute mastoiditis.

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This paper presents a comprehensive set of theoretical investigations and industrial applications of computer-based rapid manufacturing technology for high-integrity aerospace components. Two rapid manufacturing processes have been proposed by integrating rapid prototyping, high-speed machining (HSM), reverse engineering and geometric computation theory. They have been validated through trial manufacturing of a matrix of current aerospace components embracing critical design features to be found across the aerospace industry. Applied to future development programmes, this research will provide aerospace companies the benefits of significant decrease in product introduction lead-time, savings in non-recurring product introduction costs and considerable reduction in manufacturing costs for "one off" and low volume service parts. The findings can also be applied to rapid prototype development in other industries, such as automotive and military.

(2013) 'Concise process improvement denition with case studies.', International journal of quality and reliability management., 30 (9). pp. 970-990. Further information on publisher's website:http://dx.doi.org/10.1108/IJQRM-03-2012-0029Publisher's copyright statement:This article is c Emerald Group Publishing and permission has been granted for this version to appear here http://dro.dur.ac.uk/17091/. Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited. Additional information:Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Abstract PurposeThis paper examines the efficiency and objectivity of current Six Sigma practices when at the Measure/Analyse phase of the DMAIC quality improvement cycle. Design/methodology/approachA new method, named Process Variation Diagnostic Tool (PROVADT), demonstrates how tools from other quality disciplines can be used within the Six Sigma framework to strengthen the overall approach by means of improved objectivity and efficient selection of samples. FindingsFrom a structured sample of 20 products, PROVADT was able to apply a Gage R&R and Provisional Process Capability study fulfilling the pre-requisites of the Measure and Early Analyse phases of the DMAIC quality improvement cycle. From the same sample, Shainin Multi-Vari and Isoplot studies were conducted in order to further the analysis without the need of additional samples. Practical implicationsThe method was tested in three different industrial situations. In all cases PROVADT's effectiveness was shown at driving forward a quality initiative with a relatively small number of samples. Particularly in the third case, it lead to the resolution of a long standing complex quality problem without the need for active experimentation on the process. Originality/valueThis work demonstrates the need to provide industry with new statistical tools which are practical and give users efficient insight into potential causes of a process problem. PROVADT makes use of data needed by quality standards and Six Sigma initiatives to fulfil their requirements but structures data collection in a novel way to gain more information.