The objective of this thesis is to investigate the dynamic behaviour of road traffic flow based on theoretical traffic models. Three traffic models are examined: the classical car-following model which describes the variations of speeds of cars and distances between the cars on a road link, the logit-based trip assignment model which describes the variations of traffic flows on road links in a road network, and the dynamic gravity trip distribution model which describes the variations of flows between O-D pairs in an O-D network. Some dynamic analyses have been made of the car-following model in the literature (Chandler et al., 1958, Herman et al., 1959, Disbro & Frame, 1990, and Kirby and Smith, 1991). The dynamic gravity model and the logit-based trip assignment model are both suggested by Dendrinos and Sonis (1990) without detailed analysis. There is virtually no previous dynamic analysis of trip distribution, although there are some dynamic considerations of trip assignment based on other assignment models (Smith, 1984 and Horowitz, 1984). In this thesis, the three traffic models are considered as dynamical systems. The variations of traffic characteristics are investigated in the context of nonlinear dynamics. Equilibria and oscillatory behaviour are found in all three traffic models; complicated behaviour including period doubling and chaos is found in the gravity model. Values of parameters for different types of behaviour in the models are given. Conditions for the stability of equilibria in the models are established. The stability analysis of the equilibrium in the car-following model is more general here than that in the literature (Chandler et al., 1958, Herman et al., 1959). Chaotic attractors found in the gravity model are characterized by Liapunov exponents and fractal dimension. The research in this thesis aims at understanding and predicting traffic behaviour under various conditions. Traffic systems may be monitored, based on these results, to achieve a stable equilibrium and to avoid instabilities and chaos.

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In the late 1970s and early 1980s, conservationists' concern about the loss of wildlife habitat on farmland escalated into open conflict with farmers, the conflict being heightened by controversy surrounding the passing of the Wildlife and Countryside Act in 1981. An improved understanding of the attitudes of farmers and conservationists would help ensure the most appropriate measures are adopted to resolve or avoid such conflict. This research therefore compared the attitudes of farmers and conservationists in Bedfordshire in two pairs of surveys. In the first, free-ranging interviews were used to establish the range of opinions on farming and conservation held by the two groups. In the second, Fishbein and Ajzen's theory of reasoned action was used as the framework for a more detailed comparison of the differences in attitudes between the two communities. The correlation of attitudes and social pressures with farmers' behaviour was also explored for three conservation-related activities about which there was conflict: hedge management, pesticide use and straw disposal. The first survey revealed a complex matrix of shared, complementary and conflicting beliefs and values between and within the two communities. Examples of conflicting values included those concerning land ownership and freedom of individual action versus stewardship, and pride in an efficient, productive and tidy farm versus a wilder countryside. The second survey showed that while farmers agreed with conservationists about the advantages of conservation expressed in general terms, once decisions about specific farm practices were involved, attitudes to conservation and wildlife were far outweighed by attitudes to farming and business considerations. Social pressures on farmers from conservationists were minimal; the strongest social pressures came from within the farming community itself and these generally served to perpetuate the dominant farming values. Although the theory of reasoned action provided a valuable means of exploring the role of attitudes, social pressures and behaviour in the conflict, some limitations in the use of the model in these complex circumstances were found. In particular it did not allow a distinction to be made between self-interested and deeply held values; the recommended method of constructing and scoring a behaviourial index was inappropriate where value judgements were involved; and respondents experienced difficulty in distinguishing between beliefs and values when evaluative opinion statements were used. Some suggestions for overcoming these limitations are made.

The planning policies of South Yorkshire County Council are based on the philosophy of helping the "have-nots". From these policies a number of hypotheses concerning accessibility to and by public transport have been defined and tested in the Sheffield study area to gauge the extent to which the policies have been implemented. The literature on accessibility is reviewed with attention to recent work concerning accessibility by public transport. The Sheffield study area is described and the Structure Plan and other planning documents of South Yorkshire County Council are assessed with regard to policies relating to accessibility and public transport. Recent changes in the level of bus service provision in the study area are summarised. Access to bus services is investigated in terms of walking and waiting times for 170 sampling points. Overall the route density - service frequency trade-off is found to be optimal. The spatial variation in the walking and waiting times is such that areas with high proportions of people dependent on public transport do not have more accessible bus services than other areas. Access to bus services is investigated further in the Mosborough area with the relationship between the introduction and improvement of bus services and the occupation of new housing being studied. Accessibility by public transport to specific facilities is investigated. In spite of Structure Plan policies little improvement in the accessibility of five district shopping centres in Sheffield has taken place. Areas with poor access by bus to sports centres and public libraries are defined and possible locations for new facilities evaluated. In the first ten years of its existence South Yorkshire County Council has supported policies relating to improvements in accessibility and public transport. The work reported in this thesis indicates that the implementation of such policies has not always been achieved.

This research project aims to explore the hypothesis that a Community Technology approach can be considered appropriate for reclamation and recycling activities, and to investigate the opportunities for reclaiming and recycling domestic wastes viably at a 'community' scale. A framework is first established to define a Community Technology approach, and then used to assess the compatibility of reclamation and recycling technologies to this approach. 'Community '-scale reclamation and recycling in Britain, together with some examples from the USA, is examined and the 'state of the art' for both areas of activity described. 'Community'-scale is interpreted as relating to groups of people of less than 10,000, defined as neighbourhoods (of between 100 and 1,000 people) and communities (of 1,000 to 10,000 people). Initial analysis identified only three recycling processes with potential as 'community'-scale activities; all concerned with waste paper recycling. One of these, a neighbourhood-scale technology, was chosen for a detailed feasibility study. The process involves recycling waste paper into sheets of drawing or printing paper suitable for use as 'art' paper, in particular as speciality printing paper, or as sugar paper in schools. The feasibility study was carried out using design and evaluation methods, to evaluate the technical and economic feasibility of the process and to investigate what role it might play in the community, in particular in relation to promoting greater community self-reliance. The results show that this technology would not be financially or economically viable as an independent enterprise but indicated additional non-quantified social benefits and hence a possible non-economic role in the community. Some possibilities of educational and job creation roles are explored.

Air transport is an important part of any major domestic transport system. Consequently significant insight, analysis and methodological effort is necessary to devise an analytical model of a domestic air transport network with a view to the optimisation. Since the advent of airline deregulation in the US in 1978, most domestic airlines have adopted a routing and scheduling strategy known as hub and spoke. The adoption of this system presents a major change to network planning and operations for most airlines. The hub and spoke system proposed in this dissertation is for developing countries and based on the domestic Iranian air transport network. The aim of the research is to devise a practical domestic air transport network system, capable of dealing with strategic aspects of network planning and evaluation.

The following research looks into the concept of sea-air intermodality, a combination of two or more modes of transport for the carriage of goods from origin to destination. The study examines why and how this form of transport evolved to become a viable alternative to the conventional single modes of ocean and air transport. The viability of the sea-air mode depends on various equally important factors which are analysed in depth, with a special emphasis on the sea-air transfer port. fn this context, research findings of the world's existing sea-air hubs are recorded and evaluated in terms of their present and future trends. At a sea-air transfer hub, ocean cargo is converted to direct air freight, thus adding new volumes of air cargoes. In this respect, sea-air plays a positive role in the present and future development of the air freight industry. The impact of the sea-air mode can be most clearly seen in the case study analysis in Chapter 10 of this thesis, whereby the potential for 'convertibility' of large portions of low density ocean cargoes to the sea-aix mode, is successfully demonstrated.

This thesis sets out to provide a model for the calculation of private car trips to large foodstores based on local area household characteristics. It recognises the weakness in predicting private-car trips to large stores using trip-rates obtained from surveys of stores in other areas. The trip generation model that is sought must be easily applied and must use readily accessible data. It is proposed therefore that a relationship be sought between private- car trips to the stores and the household characteristics, obtainable from census data, of the local catchment area. The model thus obtained would be used for strategic planning control.