Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Composites have been used for a number of years in different sectors, including the aerospace, marine and construction industries. It is generally acknowledged that, compared to some traditional materials such as steel or aluminium, their design should aim for a higher utilisation ratio and ensure that proper attention is given to detailing, partly in order to offset higher material costs but also because of increased sensitivity to inhomogeneities, defects and, more generally, deviation from nominal properties. Coupled with the higher number of alternative designs that may be produced owing to directionality of properties, and the availability of many different material systems, the design and analysis tasks for composite structures need to be based on advanced and refined methods and tools. In this respect, finite element analysis is one such tool that can furnish the required information on structural response subject to general loading conditions. However, finite element analysis of composite structures is often undertaken by adopting some idealisations that are more appropriate to homogeneous materials, for example by making conservative assumptions regarding mechanical properties and geometric tolerances, in the absence of procedures that can account realistically with the spatial variation of such parameters within a component or structure.The aim of the proposed combined project is to develop a robust software tool for the design and analysis of composite plates, shells and sandwich panels, taking account of the random variability in geometric tolerances and mechanical properties, in other words accounting for random stiffness and strength influences on the predicted response of composite structures. The project combines experimental work, analytical and numerical modelling, in developing the required input models and algorithms for stochastic finite element analysis of composite structures. It brings together engineering materials technology, structural engineering and life cycle design, and strongly links these fields with topics in applied mathematics, such as optimisation and uncertainty modelling. In terms of academic partners it brings together two groups with distinct track records in relevant fields who can only achieve the overall project objective by working closely together. Hence, in addition to the deliverables to the engineering community, it is believed that the project will enhance significantly the research capability of the two groups, and will allow further research to be undertaken on the foundation that will be created through the execution of this project.

The drive towards lighter ships and thinner plate is restricted by the significant increase in distortion as the plate thickness decreases. Although welding has been the preferred process for metal joining for the last fifty years, distortion of the welded structures remains a major problem - typically, for a 6 mm thick plate distortions can be on the order of 60 mm. A recent study by the US Naval Sea Systems Command has estimated that the cost of distortion can up be to $3.4 million (approx. 2 million) per ship. While it is not expected that distortion can be eliminated completely, a reduction in the magnitude of the distortion will reduce significantly the costs to UK industry.In this work, the neural network approach, in conjunction with experimental measurements and the finite element method will be used to study the relationship between distortion of welded ferritic steel plates and the design parameters. The two key aspects of the problem, which will be investigated, are the interaction of process and production parameters in causing distortion and the influence of pre-existing (residual) stresses in the plate. By modelling the distortion process using material, design and welding parameters, the parameters can be optimised to minimise the resulting distortion. An existing artificial neural network (ANN) will be extended to allow examination of the distortion of the welded plate. The ANN will be trained, using results from measured plate and those obtained from a finite element code, and validated by the experimental work undertaken in the research program, to enable it to estimate plate distortion under a wide range of conditions. The combined effort will thus identify the parameters which cause distortion, assess the significance of each parameter and propose techniques to reduce distortion in welded plate.

Wireless networks have become an essential and established part of modern society. These networks require the siting and configuration of transmitters (base stations) that provide service coverage and network capacity. However, the problem of determining the correct locations and the many ways to configure each transmitter at each site is a diffcult problem both to accurately model and to solve. Mathematically it is important to determine so-called lower and upper bounds. Lower bounds provide information on the set of minimum requirements for network operation, while upper bounds are particular instances of network solutions. If thelower and upper bounds match each other a gauranteed optimal network is obtained.This project is aimed at eliminating the lack of methodolgy and techniques for deteriming upper and lower bounds for the comtemporary cell planning problem. The research will permit both the optimality of existing and new networks to be assessed and potentially enhanced.