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In an age of rapid global change the roles that engineers fulfil are also changing rapidly. This research programme seeks to establish the views of practising engineers about the future demands that will be placed upon them and then examines the views of engineering educators on the approaches that can be taken to prepare engineers for these future roles. The research focused upon related developments in engineering in two countries, Malaysia and the United Kingdom (UK), and in two engineering disciplines, civil and manufacturing engineering. The methodology employed in the first phase of the research was a scenario-based approach in which engineers were asked to assess the Implications for engineers of two major change developments, triggered by information and communication technology (IT); 'processes improvement' and 'globalization'.

Anecdotal evidence from experienced engineers suggest that barriers to creativity are often due to the limitations of current technology, methods and support systems (Baird, Moore, & Jagodzinski, 2000). The aim of this research was to explore what the perceived barriers to creativity are and how they are circumvented by design engineers working in New Projects Engineering (NPE), Rolls-Royce Aerospace (Bristol). Semi-structured interviews with four employees working in engineering design comprised a Scoping Study. This provided a general overview of the major issues perceived by the design engineers regarding barriers to creativity and resulted in six themes being identified. These themes were used as a framework for a Design Group Interviews Study that followed. Sixteen engineers comprising project managers, team leaders, experienced designers and new designers, graduate employees and trainees were interviewed using the same method. Using grounded theory to analyse the data, sixteen categories were drawn from the data. Confirmation of the findings was achieved through presentations and workshops with different groups from Rolls-Royce, and the development of an Interrelationship Digraph illustrating the relationships between the categories. The second phase of the research focused on the phenomena under current working conditions. In the Tracking Study interview diaries recorded with thirteen design engineers over an eight week period highlighted the salient issues relating to their perceived barriers to creativity. Thirteen categories (some of which could be mapped onto the previous categories and some which were new) were drawn from the data. Validation of the categories was achieved through direct observations of two design engineers in the week long Shadowing Study and completed this phase of the research. Mapping and interpretation of the findings in relation to the literature obtained further verification. From these analyses it was becoming evident that perceived barriers to creativity were present at iii many different layers of the enterprise from a macro, organisational level to the microenvironment of the individual design engineer. The final phase entailed the development of a conditional/consequential matrix model to illustrate the relationship between the macro and micro conditions, under which barriers to creativity were investigated, leading to the development of a theory. The final conclusions and suggestions for improvements demonstrate the relationship between high/low barriers and high/low creativity. The research has shown the benefits of taking an interdisciplinary socio-technical approach and has highlighted the importance and relevance of the social dimension, as well as the technological, in the investigation of engineering design. iv

The work described in the thesis is directly related to footwear technology, and may have wider applications. The upper and insole of a shoe are made from components cut from flat sheet material, which must be shaped to conform to the curved surface of a last. The pattern for the component is a map of the curved surface. Two methods for constructing plane maps of curved surfaces are described. One is based on a tree drawn on the surface, whose branches are each mapped isometrically on to a plane. Some well-known map projections used by cartographers fall into this category, as does a patented method of constructing shoe patterns. The second is an optimisation method: the ideal mapping is an isometry, (only possible if the curved surface is developable) and a norm is constructed which measures the amount by which any actual mapping departs from an isometry. The optimal mapping is the one which minimises the norm. Analysis shows that the principal directions at the boundary of the map are along and at right angles to the boundary, and that the principal scale across the boundary is unity, but the actual construction of an optimal map can only be performed by an iterative computer program. Examples are given of maps of shoe components and of portions of a sphere; the maps may include plots of the principal lines. The limitations imposed by the presence of seams are indicated, and a theory of the closed seam is worked out. The whole idea of optimal maps is set in the context of a comprehensive programme for the computer-aided design of footwear.

An experimental study of the erosion rate of cavitating flows in water past three different types of configurations for velocities of 24 to 40 m/s and cavitation number of 0.01 to 0.15 is presented. Within these velocity and cavitation number ranges the damage of each configuration is studied using the weight loss technique and also the surface deformation technique. The effect of flow velocity, cavitation number and cavitating source size on both the weight loss rate and surface roughness rate in the steady state zone is investigated. The investigation showed that the weight loss rate increased as WLR - un, the values of n varied widely depending on the cavitation source shape and size, erosion place and specimen's material. By relating the weight loss to the surface roughness for different configurations, a good correlation between them was obtained. This correlation is independent of the hydrodynamic factors and the source shape and size. A general classification of the cavity mechanics is presented based on the damage patterns, the magnitudes of the damage and the visual observations at similar flow conditions produced by various configurations. Based on the hypothesised bubble energy spectrum suggested by Hamnitt and the physics of the phenomenon of cavitation erosion as currently understood, theoretical models (semi-empirical equations) for predicting erosion rate are presented for two main types of cavitation. The effect of flow velocity and cavitation number on the pitting rate over aluminium foil surfaces are investigated for different configurations. In addition, a theoretical correlation between pitting rate per unit width, the maximum pitting rate per unit area and the cavity length is obtained. An experimental study of the variation of the cavity length with cavitation number for four different configurations is presented and a simple theoretical model is presented for the variation of cavity length with cavitation number produced by a bluff body. The variations of cavitation noise and both the weight loss rate and the pitting rate per unit width for different configurations are compared. The results indicate that there cannot be an exact correlation between erosion and the sound pressure level, and, on the other hand, there is no absolute relation between the sound pressure level and the severity of erosion.

This thesis describes an analytical and experimental study to determine the mechanical characteristics of the pump mounting, bell housing type. For numerical purposes, the mount was modelled as a thin circular cylindrical shell with cutouts, stiffened with rings and stringers; the boundary conditions were considered to be either clamped-free or clamped-supporting rigid heavy mass. The theoretical study was concerned with both the static response and the free vibration characteristics of the mount. The approach was based on the Rayleigh-Ritz approximation technique using beam characteristic (axial) and trigonometric (Circumferential) functions in the displacement series, Love - Timoshenko thin shell theory. determine the effect of the supported in association with the Studies were carried out to heavy mass on the static response, frequencies and mode shapes; in addition, the effects of stringers, rings and cutouts on vibration characteristics were investigated. The static and dynamic formulations were both implemented on the Hewlett Packard 9845 computer. The experimental study was conducted to evaluate the results of the natural frequencies and mode shapes, predicted numerically. In the experimental part, a digital computer was used as an experiment controller, which allowed accurate and quick results. The following observations were made: 1. Good agreements were obtained with the results of other investigators. 2. Satisfactory agreement was achieved between the theoretical and experimental results. 3. Rings coupled the axial modal functions of the plain cylinder and tended to increase frequencies, except for the torsion modes where frequencies were reduced. Stringers coupled the circumferential modal functions and tended to decrease frequencies. The effect of rings was stronger than that of stringers. 4. Cutouts tended to reduce frequencies; in general, but this depends on the location of the cutouts; if they are near the free edge then an increase in frequencies is obtained. Cutouts coupled both axial and circumferential modal functions. 5. The supported heavy mass had similar effects to those of the rings, but in an exaggerated manner, particularly in the reduction of torsion frequencies. 6. The method of analysis was found to be a convenient analytical tool for estimating the overall behaviour of the s6ell with cutouts. Proposals are offered regarding further relating work. Key words: Pump mounting ~ Shells 1 Rayleigh-Ritz ~ C.A.D.

The processes of data generation and organization present a real challenge in large scale engineering and architectural analysis and design problems. The main theme of the thesis is to evolve concepts and techniques that would overcome the present day problems of data preparation in engineering structural analysis. 'Formices' and 'plenices' are the two key concepts in the approach. These concepts are used to describe various features of a structural form in algebraic expressions that are easily understood and manipulated. For a structure considered as a system of finite number of elements, the topological properties, namely, the interconnection pattern of the elements, general pattern of the joints, position of the loads and constraints are all formulated through the concept of formices; and the geometric particulars, material properties, intensity of the loads and other aspects of the system are expressed in terms of plenices. The nature of plenices, also, provides a means for classification and organization of various pieces of data in a desired manner. An application of these concepts is exemplified in terms of skeletal structures.

Formex algebra is a mathematical system that may be used in the representation and processing of any sort of configuration, where 'configuration' is a term used to refer to a collection of any kind of entities. The algebraic system is modelled on requirements of data processing in engineering structural analysis. The primary aim is to provide a means for solution of problems related to the arrangement and disposition of constituent entities of structural systems, such as members, joints, loads and constraints. The basic approach is to represent the interconnection pattern of a structural configuration by a formex and then use this formex as a basic skeleton to which other aspects of the system, such as material properties and geometric particulars, may be related. The present work examines the concepts of formex algebra and makes a contribution in the practical aspect of formulating formices representing interconnection patterns of structural configurations. Also, because geometric particulars play an important part in specifying the physical properties of a structural system, the problem of relating geometric information to the formex representation of a configuration receives special attention in this thesis.

This thesis describes a study of the shear vane test which includes its history, a comprehensive review of the present state of knowledge concerning its analysis and interpretation and an investigation into the effect various factors have on it. A laboratory test program using a large instrumented shear vane allowed the shape of the shear stress distribution to be measured at the blade edges. A photoelastic and radiographic study on model vanes demonstrated the generation, size and shape of the shear zone around the mid-point of a vane. These measurements are shown to confirm analytical predictions. The influence of progressive failure on the interpretation of the vane test was assessed by means of a strain hardening - strain softening soil model. It is shown that the apparent strength derived from the conventional rigid - ideally plastic interpretation could be up to 18% in error, whilst the measurement of strength anisotropy by the two vane method may be overestimated by up to 30%. A field test study using a motorised vane with an electronic system to control rotation rate, examined the influence of testing rate whilst the strength anisotropy of the Brent Knoll clay was assessed using diamond vanes. The vane was controlled over a wide range of constant rotation rates, constant torques and constant torque application rates. It is shown that for Brent Knoll clay the strength is reduced with time to undrained failure by up to 40%. Finally, recommendations regarding the execution and interpretation of the vane test are presented. It is concluded that although the factors may combine often fortuitously to reveal an adequate prediction of field stability, they are uncontrolled and uncontrollable. Thus to ensure a more rational and consistent approach to design these factors should be assessed individually as well as collectively to determine their influence on the aquisition, interpretation and application of shear vane data.