Novel Application of Genetic Sequencing algorithms to optimisation of hardware resource sharing for DSP

Field programmable gate array (FPGA) technology is a powerful platform for implementing computationally complex, digital signal processing (DSP) systems. Applications that are multi-modal, however, are designed for worse case conditions. In this paper, genetic sequencing techniques are applied to give a more sophisticated decomposition of the algorithmic variations, thus allowing an unified hardware architecture which gives a 10-25% area saving and 15% power saving for a digital radar receiver.

Parameter Optimisation for Woodwind Single-Reed Models

Time-domain modelling of single-reed woodwind instruments usually involves a lumped model of the excitation mechanism. The parameters of this lumped model have to be estimated for use in numerical simulations. Several attempts have been made to estimate these parameters, including observations of the mechanics of isolated reeds, measurements under artificial or real playing conditions and estimations based on numerical simulations. In this study an optimisation routine is presented, that can estimate reed-model parameters, given the pressure and flow signals in the mouthpiece. The method is validated, tested on a series of numerically synthesised data. In order to incorporate the actions of the player in the parameter estimation process, the optimisation routine has to be applied to signals obtained under real playing conditions. The estimated parameters can then be used to resynthesise the pressure and flow signals in the mouthpiece. In the case of measured data, as opposed to numerically synthesised data, special care needs to be taken while modelling the bore of the instrument. In fact, a careful study of various experimental datasets revealed that for resynthesis to work, the bore termination impedance should be known very precisely from theory. An example is given, where the above requirement is satisfied, and the resynthesised signals closely match the original signals generated by the player.

Design Optimisation for Compression Moulded Sheet Moulded Compounds

This paper builds on previous work to show how using holistic and iterative design optimisation tools can be used to produce a commercially viable product that reduces a costly assembly into a single moulded structure. An assembly consisting of a structural metallic support and compression moulding outer shell undergo design optimisation and analysis to remove the support from the assembly process in favour of a structural moulding. The support is analysed and a sheet moulded compound (SMC) alternative is presented, this is then combined into a manufacturable shell design which is then assessed on viability as an alternative to the original.
Alongside this a robust material selection system is implemented that removes user bias towards materials for designs. This system builds on work set out by the Cambridge Material Selector and Boothroyd and Dewhurst, while using a selection of applicable materials currently available for the compression moulding process. This material selection process has been linked into the design and analysis stage, via scripts for use in the finite element environment. This builds towards an analysis toolkit that is suggested to develop and enhance manufacturability of design studies.