A simple optimization algorithm is proposed for designing fixed-structure controllers for highly uncertain systems. The method can be used to automate the loop-shaping step of the quantitative feedback theory (QFT) design procedure and guarantees robust stability and performance to the feedback loop for all parameters in the plant's uncertainty set. To avoid over-designing the system, the algorithm can be used to minimize either the asymptotic gain, the open-loop crossover frequency or the 3 dB bandwidth of the closed-loop system (nominal or worst case). The proposed algorithm is illustrated with a design example involving a hydraulic actuator, carried out within a computer aided design (CAD) environment ('StdQFT' toolbox) which has been developed by the authors. Some preliminary results of this work appeared in 2002 [1].

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We propose a simple optimisation algorithm for designing fixed-structure controllers for highly-uncertain plants. The method can be used to automate the loop-shaping step of the quantitative feedback theory (QFT) design procedure and guarantees robust stability and performance to the feedback loop for all parameters in the plant's uncertainty set. To avoid over-designing the system, the algorithm can be used to minimise either the asymptotic gain or the cross-over frequency of the open-loop system. Some preliminary results of this work have appeared in Zolotas et al. (1999)

The main intent of this paper is to highlight the design and development of a web based centralised software asset management system. It is used for archiving and maintaining in-house developed and open source domain-specific software assets. This system will aid in effective organisational software asset management and software reusability that will in turn improve the software development time, reduce the duplication in efforts for building similar assets, reduce the overall development cost and improve the software quality and productivity.

The authors present a summary of their understanding of the publications that appeared in the computing literature during the last five-year period, with the word quality as part of their title and dealing with some or other aspects of software quality assurance. Specifically, the summary covers the following eight sub-topics, viz., (i) quality models; (ii) timely QA feedback; (iii) quantitative approaches to predicting software quality and the effectiveness of software QA; (iv) optimal choice of QA methods; (v) design level QA; (vi) impact of parallel development options on software quality; (vii) continued QA efforts even after the operational deployment of the software product; and (viii) use of CASE tools and perceived value for QA at NASA JPL. This digest also includes summaries of three short papers describing ongoing research on (i) prioritizing QA efforts; (ii) QA in an Agile development context; and (iii) presenting the software quality status to stakeholders during development. Major trends observed in the summary pertain to (i) continuing software QA efforts even after the operational deployment of the software product, which may also be pertinent to the proliferation of mobile applications; (ii) presenting the current software quality status to different stakeholders using concise sets of software metrics; and (iii) the effectiveness of hybrid approach of tool use combined with expert judgment for software QA. The emphasis on software QA activities spreading throughout the software product life cycle, from its beginning to end, is clearly observed in the reviewed literature.