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No description available.

The design of modern buildings has become an increasingly complex activity. This is because of greater demands by Clients in terms of performance, quality, economy and time. These demands coupled with the complex iterative nature of design have resulted in increasing challenges in building design and in the management of the design process. The design process is information driven. Initial research by the writer showed that the main difficulties encountered during the management of the design process are information related. Information transfer and communication issues have been identified as key factors in the successful management of the process. It was concluded that current planning techniques are ill-suited for planning, monitoring and controlling building design because they neither accommodate the iterative nature of design nor permit the choice of alternatives. This research sought to develop better tools to aid design managers in improving the management of the process. Although all phases of the design process were examined, the main focus of this research was the Conceptual and Schematic design stages. To investigate these stages a generic data flow model was developed using the structured analysis diagramming technique of Data Flow Diagrams. The model was based on data from preliminary case studies and was validated by interviews with construction industry professionals. Industry feedback showed that improved management of the design process should not only include better techniques for planning and scheduling but also allow design managers to investigate the iterations between design tasks and predict the effects of different scenarios. Matrix partitioning techniques were used to identify ioops of iterative design tasks in the data flow model. A Discrete Event Simulation Model was developed to predict the effects of different scenarios. This model was based on data from the Data Flow Model and the identified iterative design loops. In addition, dynamic factors input by the user such as the durations and resources of the design tasks allowed the examination of the effects of different scenarios of information related criteria. These criteria were identified from industry survey and interviews. The simulation model was rigorously tested and validated through subsequent case studies and review by industry practitioners. The thesis concludes that the use of Data Flow Modelling in conjunction with Matrix Analysis and Discrete Event Simulation techniques provides a powerful tool for assessing the impact of change within the design process and could form the basis for managing and planning multi-disciplinary design work.

The operation of an efficient and integrated site management system is one of the problems that still requires a considerable amount of attention in most of the construction companies in U.K. This thesis describes the research I have undertaken on this problem and how a computer-aided construction management system can assist in solving the problem. The thesis has been divided into three sections according to the research. The first section describes the research I have undertaken as surveys on; the literature as an existing knowledge of efficient and integrated site management systems; what systems are applied on site and the degree of satisfaction from them; the facilities that can be provided by the available site management software. From the above surveys, the problem has been identified and the objectives established for the research. The second section of the thesis describes my development of a software model to facilitate collecting, processing and analyzing data from the site for producing control data and reports. The section also describes the integration of the model to the other construction management systems (i. e. estimating, planning, cashflow forecasting and valuation), as well as being self-contained. The last section of the thesis describes my research in investigating how well the model achieved the research objectives. This section described a number of case studies based as a demonstration of the model, its functions and mechanism, using slides and on-computer seminars. From this evaluation I have established a list of comments, some of them were used to modify the model or as conclusions and recommendations for any future research in this field.

The aim of the study described in this thesis is to investigate the application of expert system technology to acrylic fibre production, with a particular emphasis on knowledge acquisition requirements. In doing so, it is intended to provide an understanding of the requirements and appropriate techniques for the effective application of expert systems in the process industries; The scope of the study is limited to process fault administration which involves detecting, diagnosing arid correcting abnormalities in process operation. A methodology is provided for the systematic development of expert systems within the defined area of application. An important phase in the development methodology is that of expert system specification. This involves an analysis of expert behaviour and the specification of expert system functionality: In order to assist system specification, generic knowledge types and human expert activities have been identified within the context of process fault administration. Knowledge acquisition is discussed in terms of the requirements during each phase of the proposed development methodology. A detailed review is given of the available techniques for knowledge acquisition and an assessment is presented of the most appropriate techniques to apply during each phase of the methodology. A new knowledge acquisition technique is described. The technique is designed to record knowledge of process operation and process fault diagnosis. It is based on a hierarchical decomposition of the process in terms of process objectives. Two complementary forms of knowledge representation are produced: a hierarchy diagram which shows the dependency relationships between individual process objectives and a task statement table which provides a more. detailed explanation of the objectives. Finally, three. case studies are described in which the techniques described in the thesis were applied and developed.

The aim of this research was to understand and solve problems associated with the integration of a Machine Planner within a product model environment. This work was carried out in conjunction with other researchers, pursuing parallel integration issues related to pre-production proving and product data representation. Product data representations of component level planned, processes and feature level process data have been explored as sub-sets of -a product data model to aid integration. Geometric queries on a cell decomposition solid, model. have been explored as a means of providing feature geometric interaction data, while the dimensional interactions between features have also been addressed. Product data representations have been modelled using a prototype software tool, providing an environment for the exploration of the integration of a Machine Planner using a feature based design approach. Necessary Machine Planning functions have been implemented, using the ADA programming language, to explore the integrating capability of the product model environment, concentrating on the use of a prismatic benchmark component. Using the experimental implementation, setup and operation plans have been produced and machining part programs generated from product model representations of variants on the benchmark component. These have been successfully machined using a3 axis vertical machining centre. Such experiments, as well as others in conjunction with co-researchers, have shown that a product data model can provide a common base of data for the integration of a range of design and manufacturing activities.

An important element for the integration of CAD/CAM is the representation and handling of data used during the design and manufacturing activities. The use of features and product modelling techniques bring a better handling of this data and provide CAD/CAM with an excellent platform for integration. The thesis explores the use of a predefined set of features in a product modelling environment for the design and machining of rotational components. Theword features in this research implies a set of functional, geometrical and technological information with a unique form. Those features are pre-defined and comprise of a limited number of elements which carry the information related to design and manufacturing activities. The thesis is divided into three main parts. The first part contains a review of topics related to the research e. g. group technology, component features, CAD/CAM and also contains a literature survey of related research works. In the second part the "features" are defined and presented. Also the product modelling environment is explained and the basic rule based procedures which are used to automatize the operation planning activities are presented. In the last part a description of the case-studies used for automatic NC code generation is presented followed by a discussion of the results. Lastly, the conclusions are drawn and ideas for further work presented.

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Building contractors are unhappy about the existing post-tender use of the bills of quantities, particularly the way in which data produced by the estimator may be independently produced again or amended to a suitable format by other management functions. This research aimed at proposing better formats and presentations for the estimating data in order to reduce the repetition and re-work involved in the post-tender use of estimating data, hence to reduce the complexities in data flow in building contractor organizations. The work was primarily carried out for the Sri Lankan industry. To establish the scale and nature of the problem, past work on the format and presentation of estimating data and its current management was studied through literature, interviews and discussions with professionals in ten case studies. Proposals were formulated defining; an efficient classification and coding system, a well defined library structure, a new format to the contractor's copy of the estimate, and effective uses of the computer. The main proposal was to split the unit rate into its components and to provide a breakdown of resource requirements for each bill item. The documents prepared in two test projects were used to demonstrate the feasibility of the proposals in the earlier case studies, and feedback was obtained on the use and extent of use of the improved estimate in post-tender works. A live project was undertaken to investigate the practicability of implementing of the proposals. Finally, an independent survey, without disclosing the results derived from test projects, case studies and the live project was carried out to assess the acceptability of the proposals in the whole industry. All practical work was undertaken in Sri Lanka. The main conclusions derived from these works are; Any research that would investigate the contractor's efficient post-tender use of estimates hould be addressed to contractor organisations; and any proposal that would improve the contractor's data management should be based on contractor's presentation of the estimate. Although the contractors widely use the estimate in their management functions, the full potential is not obtained throughout the contract. Substantial re-work exists in the use of estimate in contractor's post-tender works. The average extent of use of the estimating data was measured at 50% the other 50% of data required re-work. Proposals presented in this research would increase the extent of use of the estimate, hence improve the contractor's data management. The new average extent of use of estimating data (after the introduction of proposals) derived from case studies was 75%. This new average, when compared with the earlier average (50%) showed a 50% possible improvement in the extent of use of estimate in the industry. Test projects, the live project and the independent survey, all showed that the proposals are not only feasible and practicable to implement in contractor organizations, but also acceptable in the whole industry as solutions which would improve the extent of use of the estimate and reduce the complexity of data flow in contractor organizations. The significance of these conclusions is that any contractor organization can adopt the proposals to improve their management because not only has their practicability been investigated but also their acceptability in the whole industry in Sri Lanka as a solution to data complexities is established. The conclusionsa re also of value to other countries.

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