This thesis results from the following work: (1) We have carried out a comprehensive study of Islamic geometrical patterns. More then 300 patterns have been studied. We have given a critique of the work of previous authors on this subject and have discussed our own Ideas on the evolution of Islamic geometrical designs. (2) We have performed symmetry analysis on the patterns and classified them according to their symmetry groups. (3) We have extracted numerical data for efficient generation of the patterns based on the analysis In (2). The data for more than 300 patterns Is provided on the disk. (4) We have developed a mathematical formalism based on group theory and constructed algorithms suitable for the generation of the patterns using computer graphics. (5) the algorithms have been proved by writing an Interactive computer graphic program called Islamic Geometrical Patterns ' IGP'. A library of geometric Islamic patterns has been constructed. (6) At Lite end of this thesis, In an Appendix, we have provided suggestions for further extension of this work.

No description available.

No description available.

No description available.

Cellular manufacturing is widely viewed as an exemplary form of manufacturing organisation for small batch size production. A UK survey states that over 75% of British engineering industry have introduced or are planning to introduce cellular manufacturing methods in an attempt to improve competitiveness through improved product quality, responsiveness and flexibility (Ingersoll Engineers, 1990). Cells are known to foster these improvements through a focus on the methods of production and more co-operative work structures. The widespread adoption of cellular manufacturing methods has warranted research into and practical application of human-centred forms of work organisation. This approach seeks to improve the use of people and technology to develop more robust and effective manufacturing systems. The human-centred approach to job design and systems development is considered essential for improving Europe's future competitiveness (EC MONITOR FAST Programme, 1989-1992). The design of cellular manufacturing systems is a complex task involving the joint consideration of material flow, machines, people and control issues. The development and practice of human-centred job design in ceRs is an area with little formal process. There is no coherent academic model that embraces all the relevant issues in cell job design. This research develops and validates a generic model to facilitate human-centred job redesign in cell systems. The model adopts an open systems perspective and unifies three fields of job design embracing socio-technical, work organisation and function allocation issues. These levels provide a structure for the model. The model explicitly represents factors affecting job design by features defined at the three levels of analysis. The features are comprehensive and are representative of the issues encountered in each field of job design. The features are not independent and are interelated between levels of analysis. The model describes in quantitative terms the relationships between these features to provide a means for stepping through the cumulative effects of job design changes from one level to the next. An application procedure to use the model, derived from the research methodology in this thesis, is described outlining the data capture and analysis activities for developing situation sensitive pictures of cell job designs. The combined model and application procedure are tools to help the model users accumulate knowledge on the factors affecting the design of jobs in cells. Field research was carried out in a British manufacturing company over a period of fifteen months to develop and validate the model. CeH job design models were developed for four dissimilar cell systems varying in terms of cell age, work organisation and technical complexity. The model demonstrates its generalisability and sensitivity by accurately describing job design in four cell systems.

No description available.

Developments in technology have meant that computercontrolled imaging devices are becoming more powerful and more affordable. Despite their increasing prevalence, computer-aided design and desktop publishing software has failed to keep pace, leading to disappointing colour reproduction across different devices. Although there has been a recent drive to incorporate colour management functionality into modern computer systems, in general this is limited in scope and fails to properly consider the way in which colours are perceived. Furthermore, differences in viewing conditions or representation severely impede the communication of colour between groups of users. The approach proposed here is to provide WYSIWYG colour across a range of imaging devices through a combination of existing device characterisation and colour appearance modeling techniques. In addition, to further facilitate colour communication, various common colour notation systems are defined by a series of mathematical mappings. This enables both the implementation of computer-based colour atlases (which have a number of practical advantages over physical specifiers) and also the interrelation of colour represented in hitherto incompatible notations. Together with the proposed solution, details are given of a computer system which has been implemented. The system was used by textile designers for a real task. Prior to undertaking this work, designers were interviewed in order to ascertain where colour played an important role in their work and where it was found to be a problem. A summary of the findings of these interviews together with a survey of existing approaches to the problems of colour fidelity and communication in colour computer systems are also given. As background to this work, the topics of colour science and colour imaging are introduced.

This thesis adopts the new STEP standard and accompanying methodologies to solve an important problem facing manufacturing industries: integrating CAD tools and product data information. Using the STEP methodology, a first attempt to develop a multi-Application Protocol application was made, which led to the development of a generic electronic product model that became the conceptual schema of an object oriented database. This model has been actually implemented and tested. The methodology adopted led to the proposal of a new extended Application Protocol designed to meet information requirements of the manufacture of electronic products. The generic model for electronic products is proposed and developed employing STEP resources and methodologies. Using STEP's information modelling language, EXPRESS, extra data constructs were developed to satisfy the information requirements of the model. Novel aspects of the model include: the combination of all aspects of the product, both electronic and mechanical; and the extension of the model over six different STEP Application Protocols. The work involved the proposal of a new extended Application Protocol to meet information requirements of electronic products, and the development of a detailed model of a generic Printed Circuit Board (PCB). A unique feature of this PCB model is its compatibility with any future PCB CAD tool claiming compliance to STEP. The models conformance to STEP was ensured via extensive validation and conformance procedures. Problems related to the implementation of this new standard in the electronics industry were identified and possible solutions discussed. This work includes an industrial case study where an actual activity model of an engineering organisation was developed; the proposed generic model implemented and tested; and the actual data instances of a product generated and stored in a universal object-oriented product database. The implementation of the generic model provided the engineering organisation with an integrated platform for product data, which facilitated the implementation of concurrent engineering practices.

This thesis describes the development of a diagnostic tool to identify potential weaknesses in the interfaces between the key functions involved in new product development within manufacturing organisations. It comprises three parts: Part One introduces the field and reviews the literature. It discusses the subject of new product development (NPD), describes how the NPD process has evolved and outlines the key success factors which have been found to apply. It identifies and summarises the key issues which have influenced NPD and discusses the role that teams have had within the field. Key functions and their respective interfaces are identified and the barriers which exist between these functions assessed. A theoretical framework is presented which proposes that problems within these functional interfaces can be overcome by developing appropriate solutions based on accurate diagnosis of imbalance of functional perceptions within organisations. Associated research hypotheses and methodology for the research programme are also presented. Part Two describes the development and testing of a questionnaire to achieve this diagnosis. This details the identification of core issues through interviews in sample companies, initial testing of a questionnaire and the subsequent revision and retesting. Rationalisation of the questionnaire using both item and factor analysis techniques are then described and, following final testing, the use of these same techniques to develop a scoring system are also detailed. Part Three discusses the findings from the research programme and draws conclusions. The results obtained from the use of the diagnostic questionnaire within the participating organisations are compared with the literature and the development of the diagnostic questionnaire is evaluated. Finally the research hypotheses are examined and tested and conclusions relating to both the findings and the questionnaire development are drawn. Finally recommendations for the future use of the developed diagnostic tool are made.

No description available.