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It has been broadly recognised that today’s manufacturing organisations face increasing pressures from continuous and unexpected changes in the business environment such as changes in product types, changes in demand pattern, changes in manufacturing technologies etc. To enable manufacturing organisations to rapidly and timely deal with these changes, operational decisions (e.g., process planning and production scheduling) have to be integrated with dynamic system restructure or reconfiguration so that manufacturing organisations do not only use the flexible resource utilisations to deal with these changes, but also can dynamically reconfigure their existing system structures in response these changes. A manufacturing system concept and implementation methodology is proposed by the Exeter Manufacturing Enterprise Centre (XMEC), which is called the Dynamically Integrated Manufacturing System (DIMS). The overall aim of DIMS is to provide a systematic modelling and control framework in which operational decisions can be integrated with the dynamic system restructuring decisions so as to help manufacturing systems to dynamically deal with changes in the business environment. This PhD research is a part of DIMS research, which focuses on the investigation on operational control in DIMS. Based on the established agent-based modelling architecture in DIMS, this research develops two agent bidding mechanisms for the hierarchical control of production planning and scheduling. These two mechanisms work together to assist manufacturing systems in making optimal and flexible operational decisions in response to changes in the business environment. The first mechanism is the iterative agent bidding mechanism based on a Genetic Algorithm (GA) which facilitates the determination of the optimal or near optimal allocation of a production job containing a set of sub-jobs to a pool of heterarchical resources. The second mechanism is the hierarchical agent bidding mechanism which enables product orders to be cost-efficiently and flexibly planned and scheduled to meet the orders’ due dates. The novelty of this mechanism is that it enables orders to be fulfilled within structural constraints of manufacturing systems as far as possible and however enables resources to be regrouped flexibly across system boundaries when orders cannot be fulfilled within structural constraints of manufacturing systems.

The purpose of this study was to formulate a guideline for developing and managing the future neighbourhoods in the Central Region of Saudi Arabia based on the cultural norms of its residents. The initial cause for this study is the conflict between the imported new planning system and the restricted culture and behaviour of the people involved. In order to achieve the main objective of this thesis, a series of studies was undertaken. The theoretical background relating to the main issues of this study are reviewed and the notion of these issues defined according to the Saudi Arabian's belief and way of life which is essential to understanding. The thesis discussed, analysed, and evaluated three types of neighbourhoods planning systems which occurred in the study area. These were the traditional, the contemporary, and the new trends planning system. These studies where primarily formulated in light of the literature review and the analysis made from the information obtained via questionnaires, interviews, observation, and public and community consultations (carried out by the researcher in the summer 1988 and summer 1989). From the analysis, the thesis concludes that the future planning of the neighbourhoods should be formulated according to a man-surrounding relationship and his needs. In order to clarify this, the thesis defined a set of recommendations for forming and managing the future neighbourhoods. These include considering the socio-cultural and the individual requirements of the residents, making the plan open-ended, and establishing a local community authority to control the implementation and the growth of the neighbourhoods. Finally, the thesis briefly explains how to implement some of the recommended guidelines which need to be clarified through using a specific case study. It recommends also some further studies in order to reinforce and generalise the findings of the thesis.

The fast and in most cases uncontrolled urban growth, in Riyadh and other Saudi urban areas, has created many deficiencies such as land speculation, urban sprawl, lagging public services and utilities, along with other developments that are inconsistent with the development plan. The purpose of the study was to identify these problems of inconsistency and provide solutions to avoid them. In order to achieve the main objective of the thesis, the problem is briefly introduced by explaining the existing urban growth problems. A review of relevant theoretical literature background was carried out, particularly on development plans, control of development, and plan policy implementation, mainly in developed countries. In order to understand the local situation the economic and social factors affecting Saudi urban growth and land development were identified. Also the procedures and government institutions involved in the planning process and the control of urban growth were introduced an d their role explained. As infrastructures and public services are one critical component of any urban development process, their scale and distribution in Riyadh were assessed. In addition a description of land ownership, local and legal rights of development, the effect of Saudi planning in developing land, the common practice and the perceived weaknesses of control of development were presented. To get some clear idea of Riyadh urban growth during the case study period (1977 - 1992), an analysis of the various land use activities and scale were conducted for that period. Then an assessment and examination of these developments was carried out to determine and identify the developments that are inconsistent to the Development Plan, and explain the causes of such inconsistencies. At the end, based on the analysis of the thesis, a suggestion of possible alternatives to control development and urban growth is given, and the thesis is concluded by recommending proposals for more effective control of development and more efficient plan policy implementation.

An essential assumption for the usefulness of near miss reporting is the common cause hypothesis: the causal pathways of near misses are supposed to be similar to those of actual accidents (such as injuries and damages). The common cause hypothesis was originally proposed by Heinrich (1931) in his seminal book "Industrial Accident Prevention". Since then, the hypothesis has been alternately supported and rejected based on a confounded view of the interdependence of severity, frequency and causation. The evidence from various studies is examined and it is concluded that the hypothesis has not been properly tested. Thus this thesis tests the validity of the common cause hypothesis. In order to develop the methodology to test the ommon cause hypothesis analytical work in the area of incident analysis and reporting was required. Thus this thesis also outlines the approaches to accident and incident analysis and makes several recommendations regarding the use of taxonomies and reporting systems. A reporting and analysis system (CIRAS) for the collection and analysis of near misses and unsafe acts and practices was developed and implemented for use in the UK railway industry. This reporting and analysis system formed the basis for the test of the common cause hypothesis. Data used to empirically test the common cause hypothesis come from one company of the UK railway industry. Three types of data were used: incidents resulting in 'fatality & injury', 'damage' or 'near miss''. A total of 240 incidents were collected via management reports and a voluntary reporting system. All incidents were coded for causal factors according to the CIRAS (Confidential Incident Reporting and Analysis System) taxonomy. A total of 750 causal factors were assigned to the 240 incidents. Analysis was performed on a comparison of the proportion of codes occurring at all three consequence levels using Chi-square analysis. Results : The CIRAS taxonomy consists of 21 individual causal factors. Only three of these factors (knowledge based, training and procedures) were significantly different across the three severity levels. It is therefore concluded that this research provides qualified support for the common cause hypothesis.

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