The main objective of this thesis is to describe the effect on cognition of the structure of CAL simulation programs used, in science teaching. Four programs simulating a pond ecosystem were written so as to present a simulation model and to assist in cognition in different ways. Various clinically detailed methods of describing learning were developed and tried including concept maps which were found to be sammative rather than formative descriptions of learning, and to be ambiguous) and hierarchical structures (which were found to be difficult to produce). Fran these concept maps and hierarchical structures I developed my Interaction Model of Learning which can be used to describe the chronological events concerned with cognition. Using the Interaction Model, the nature of cognition and the effect that CAL program structure has on this process is described. Various scenarios are presented as a means of showing the possible effects of program structure on learning. Four forms of concept learning activity and their relationship to learning valid and alternative conceptions are described. The findings from the study are particularly related to the work of Driver (1983), Marton (1976) and Entwistle (1981).

This thesis relates to the application of Artificial Intelligence to tool wear monitoring. The main objective is to develop an intelligent condition monitoring system able to detect when a cutting tool is worn out. To accomplish this objective it is proposed to use a combined Expert System and Neural Network able to process data coming from external sensors and combine this with information from the knowledge base and thereafter estimate the wear state of the tool. The novelty of this work is mainly associatedw ith the configurationo f the proposeds ystem. With the combination of sensor-baseidn formation and inferencer ules, the result is an on-line system that can learn from experience and can update the knowledge base pertaining to information associated with different cutting conditions. Two neural networks resolve the problem of interpreting the complex sensor inputs while the Expert System, keeping track of previous successe, stimatesw hich of the two neuraln etworks is more reliable. Also, mis-classificationsa re filtered out through the use of a rough but approximate estimator, the Taylor's tool life equation. In this study an on-line tool wear monitoring system for turning processesh as been developed which can reliably estimate the tool wear under common workshop conditions. The system's modular structurem akesi t easyt o updatea s requiredb y different machinesa nd/or processesT. he use of Taylor's tool life equation, although weak as a tool life estimator, proved to be crucial in achieving higher performance levels. The application of the Self Organizing Map to tool wear monitoring is, in itself, new and proved to be slightly more reliable then the Adaptive Resonance Theory neural network.

Over the past twenty years academics, industry commentators and practitioners in the field of physical distribution have been pre-occupied with the computational and technical side of computerised vehicle routing and scheduling (CVRS). Comparatively little research activity has been carried out on the user or management aspects of the technology. The current study aims to make up for this research deficit by investigating the adoption of CVRS technology in the British road freight industry. Moreover, the study evaluates the success of the software used in a strategic, tactical and operational role. The subject of the empirical analyses is the British brewing industry. The findings highlight the fact that CVRS technology is used by only a relatively small number of organisations despite being an effective means to improve the efficiency of transport operations and to provide substantial intangible benefits. The research also develops and empirically validates a model of CVRS in the organisational context. "Organisational context" means that the focus is on the organisational aspects rather than on the technical aspects of the technology. The model investigates relationships between variables and addresses two major research questions: What are the reasons leading to the apparent lack of CVRS system penetration - the "CVRS user-gap"? What are the key factors of successful implementations and subsequent use of the software? To overcome the "CVRS user-gap", the study suggests appropriate measures focusing on individuals' awareness of and attitudes towards the software rather than on improving the quality of the software. To ensure CVRS success, the potential users of CVRS should have a certain level of technological and organisational maturity. Emphasis needs to be placed on adequate system implementation. Special attention should also be given to three critical success factors: the quality of the software; the system operator's ability to use the software; and the drivers willingness and ability to adhere to the computer-generated route proposals.

This work concentrates on the newly growing science of managing tooling in conventional manufacturing. Various Tool Management (TM) problems and the approaches suggested by other researchers to solve these problems are given. This work establishes the basic structure of TM applicable to a conventional manufacturing. Systems Analysis and Design Methodology (SSADM) is used to study the information needs of a typical TM System. It is stressed that the majority of TM problems are due to unavailability of correct information. Success of any TM system depends upon having a good Information System. This work focuses on the tool planning problems in batch manufacturing. The causes of tool planning problems are discussed. The research aims to develop a generic methodology for planning the tools. The information required to carry out the primary functions of any Tool Planning System (TPS) is identified. The fundamental characteristics of different tools from the planning perspective are studied in detail. The principles on which a generic TPS could be designed are laid out. The mechanism of a Tool Planning System is developed. The TPS model is implemented using Foxpro, a DBMS. This model illustrates the concepts of planning tools with the information that can be obtained from other functions of manufacturing. The effectiveness of the developed TPS model is investigated using simulation. The impact of the TPS on the performance of a typical Job Shop Environment is studied and compared with other models with traditional stock control approaches. A suitable statistical method is used for analysing and comparing the simulation results. The advantages and the limitations of the TPS are discussed. Some of the potential benefits include, very low tool shortages, minimum number of purchase requirements and better estimation of tool inventory levels. Furthermore, the TPS acts as a firm guideline for planning the tools in time buckets.

Global competition in industry demands that organisations take steps to improve or even redesign their manufacturing systems in order to remain competitive. Such improvements invariably require considerable investment and risk. The use of computer simulation allows managers to understand the underlying dynamics of complex manufacturing systems in order to identify problem areas. The models can also be used to evaluate re-design strategies and options for improvement, thereby reducing the potential risk and increasing the likelihood of a positive return on investment However, developing a valid simulation model that represents the system to a sufficient scope and level of detail to allow confident decision making is a difficult task. The research explores the application of a novel methodology consisting of a questionnaire survey, case studies with expert model builders and action research with a steel manufacturing company. Using these research techniques, this study focuses on the crucial early phases of the simulation model development process. The research demonstrates that the combination and application of the research techniques has proved to be a powerful methodology to explore the dynamic interactions of the early stages of the simulation life cycle. The findings conclude that the simulation life cycle is highly iterative process where it is difficult to identify clear steps between the different stages of a simulation project. The model builders engage in a number of cyclic activities where there is significant interaction with the client stakeholders to ensure that the model is a valid representation of the problem. The increased use of Visual Interactive Simulation Software (VISS) has had a major impact on the life cycle by allowing dynamic models to be created at a very early stage which facilitates the interaction between model builder and client.

Constraint-based systems are increasingly being used to support the design of products. Several commercial design systems based on constraints allow the geometry of a product to be specified and modified in a more natural and efficient way. However, it is now widely recognised the needs to have a close coupling of geometric constraints (i.e. parallel, tangent, etc) and engineering constraints (Le. performance, costs, weight, etc) to effectively support the preliminary design stages. This is an active research topic which is the subject of this thesis. As the design evolves, the size of the quation set which captures the constraints can get very large depending on the complexity of the product being designed. These constraints are expected to be solved efficiently to guarantee immediate feedback to the designer. Such requirement is also necessary to support constraint-based design within Virtual Environments, where it is necessary to have interactive speed. However, the majority of constraint-based design systems re-satisfy all constraints from scratch after the insertion of a new design constraint. This process is time consuming and therefore hinders interactive design performance when dealing with large constraint sets. This thesis reports research into the investigation of techniques to support interactive constraint-based design. The main focus of this work is on the development of incremental graph-based algorithms for satisfying a coupled set of engineering and geometric constraints. In this research, the design constraints, represented as simultaneous sets of linear and non-linear equations, are stored in a directed graph called Equation Graph. When a new constraint is imposed, local constraint propagation techniques are used to satisfy the constraint and update the current graph solution, incrementally. Constraint cycles are locally identified and satisfied within the Equation Graph. Therefore, these algorithms efiiciently solve large constraint sets to support interactive design. Techniques to support under-constrained geometry are also considered in this research. The concept of soft constraints is introduced to represent the degrees of freedom of the geometric entities. This is used to allow the incremental satisfaction of newly imposed constraints by exploiting under-constrained space. These soft constraints are also used to support direct manipulation of under-constrained geometric entities, enabling the designers to test the kinematic behaviour of the current assembly. A prototype constraint-based design system has been developed to demonstrate the feasibility of these algorithms to support preliminary design.

Many UK MBA programmes adopt a collaborative approach to the Harvard style of experiential case based learning. Within such programmes there is widespread use of computers but it is not clear how this improves student learning. Research on computer support of collaborative learning in other disciplines is of limited applicability because of the dual role of student as learner and as expert. In management education such research has mainly focused on technology. Within this context this exploratory research seeks to establish how the actual use of computers in the collaborative study of cases within MBA programmes affects the efficiency and effectiveness of the learning process. Three core courses from well-respected MBA programmes are studied in detail. Student attitudes are investigated using an established instrument and an open-ended questionnaire. In each course student behaviour is observed by studying one aspect of the course in which computers are being used. Data is collected through videos, participant observation and the capture of online conferences. The three MBA programmes have comparable core curricula and computer rich environments. Delivery modes are full-time, part-time and distance so they cover a wide spectrum of the MBA student population in the UK. Six propositions arise from the investigations of which four are established by this research. These show that UK MBA students are enthusiastic about computers and believe in their ability to use them competently. Most students do use computers extensively at all stages of collaborative case based learning. However there is a marked dissonance between their attitude and actual use. If this dissonance is addressed students can improve both the efficiency and effectiveness of their learning through using computers.

Communication between different members of a design team often poses difficulties. The knitwear design process is shared by the designers, who plan the visual and tactile appearance of the garments, and the technicians, who have to realise the garment on a knitting machine and assemble it. This thesis reports a detailed empirical study of over' twenty companies in Britain and Germany, which shows that the communication problem constitutes a major bottleneck. Designers specify their designs inaccurately, incompletely and inconsistently; the technicians interpret these specifications according to their previous experience of similar designs, and produce garments very different from the designers' original intention. Knitwear is inherently difficult to describe, as no simple and complete notation exists for knitted structures; and the relationship between visual appearance and structure and technical properties of knitted fabric is subtle and complex. At the same time the interaction between designers and technicians is badly managed in many companies. This thesis argues that this communication bottleneck can be overcome by enabling designers to produce accurate specifications of technically correct designs, through the help. of an intelligent computer support system that corrects inconsistent input and proposes design suggestions that the user can edit. In this thesis this proposal is elaborated for one aspect of knitwear design: garment shape construction. Garment shapes are modelled using Bezier curves generated using design heuristics drawn from industrial practice, to create curves that look right to a designer and can be easily edited. The development of the garment shape models presented in this thesis involved the solution of unusual problems in numerical analysis. The thesis shows how the mathematical models can be integrated into an intelligent CAD system, and discusses die benefits of such a system could have for the design process.

This thesis describes a formal methodology for defining and assessing product performance and its implementation in a prototype computer system. The methodology is based on abstract descriptions of the operations that are conducted within the design process. It is, consequently, extremely generic and creates a bridge between physical product performance and actual user requirements. The methodology is based on defining product attributes in terms of observable parameters of the product in use. Defining an attribute in this way inherently reflects its required interaction with the user and consequently can truly be said to be in "user terms" A product will have a range of attributes and a performance indicator is proposed, such that the attributes are combined in a way that reflects their relative importance to the user. At the conceptual stage of the design process, when the actual product does not exist, and only some abstract representation is available, it is vitally important to be able to model or simulate and hence evaluate the product attributes. This area of design has often been associated with non algorithmic design procedures, because of its intangible nature. In this thesis the attribute methodology has been used to implement a prototype Computer Aided Design Evaluation Tool (CADET), which has been used and tested with an existing product range. The methodology being abstractly defined supports a wide range of product attributes. It also gives an indication of how the correspondingly wide range of existing analysis software could be integrated into a powerful single Computer Aided Design system. This work has resulted in the publication of two papers in refereed Journals and the presentation of eight other papers at refereed International Conferences. A list of the publications is included in the Appendices.

Control System Design methods are presented in terms of optimization techniques that incorporate Multi-Objective design criteria. Computer-Aided Control System Design (CACSD) environments make the approach easy-to-use and accessible to the practising control engineer. Two CACSD environments have been developed using different versions of the MATLAB package, one interfacing the ADS optimization package to an upgraded FORTRAN version of MATLAB, the other using Non-linear Programming algorithms coded in the PRO-MATLAB command language. In both environments, optimization problems are entered interactively and in a flexible manner using simple interpreted commands and programs. A Control System Design method has been implemented using optimal control theory and integral quadratic measures of control. The theory has been developed to incorporate a large number of design options, control structures and disturbance types. An evolutionary design process is used so that the control order and number of design criteria are systematically increased to incorporate more complex control structures and a wide set of performance objectives. In the later stages of this evolutionary design process, a Multi-Objective design strategy, known as the Goal Attainment method, is used to address multiple performance objectives.