No description available.

No description available.

No description available.

No description available.

No description available.

A detailed literature review reveals the need for further study of several aspects of road accidents to child pedestrians in urban areas. Some of these aspects are explored using data for selected residential parts of five urban areas in Britain. Road accidents in the five study areas are examined using Local Authority accident data, police accident reports, local knowledge, and data from the 1981 census of population. Variations in occurrence of these accidents are analysed using variables such as age and sex of the child, type of location, distance from home, severity, and time of occurrence. Collection and analysis of data concerning exposure on journeys to and from school and during some other uses of the roads are described. Data on journeys to or from school was collected by questionnaire from most of the schools in each of the study areas. Analysis examines several features of exposure including mode of travel, accompaniment, time spent outside, distance travelled, and the number of roads crossed. These features are analysed for different groups of people, at different times, and in different sorts of area. Where possible results are related to accidents to produce measures of risk. Data on journeys other than those to and from school, with particular emphasis on play, was collected in two of the study areas by direct observation of children on the streets. These observations were carried out to a preset schedule, using routes predefined on the basis of accident and other local information. Analysis examines the variety of children using the roads in different areas and time periods. Where possible, accident data and traffic flow information are related to the results to produce measures of accident risk. Suggestions for preventative measures, and for additional research, both within these study areas and more widely, are given.

The present thesis examines some aspects of the structure of urban space found in particular towns in the Sahara, and the peculiarities in their dual organisation of the circulation systems: the streets and the roof terraces of the houses inter-connected by another system of walkways, which are exclusively reserved for the circulation of women across the settlements or parts of the settlements. The terrace morphology is developed in different forms and at various degrees of elaboration in these urban systems, which are usually seen as the result of some external determinant factor, such as religion, with the public being wholly male and women confined to the domestic sphere. Since there are no differences in religious terms between these systems, this view cannot be adopted to account for the pronounced differences in their spatial configurations. The study argues that: i- the terrace morphology is only one instance of the spatial mechanisms which enter in the separation and integration of the sexes, the global organisation of the street system is another; ii- these mechanisms, to include the terrace system, are intimately bound up with the nature of the urban fabric of these towns, which can be characterized as poorly connected and highly segregated, with a distinctive organisation of the main streets with regard to the settlement as a whole. The dense fabric of these towns with large urban blocks creates both, the high level of segregation of the street system and larger roof surfaces; iii- both, the nature of the urban fabric and the global organisation of these systems are strongly related to the generative processes of urban formation, and the underlying rules followed in the aggregation of buildings on the ground. These rules are seen as expressions to social restrictions on relations between and within male and female groups. The computer simulations of the urban growth show that the highly segregated nature of the spatial fabric and its distinctive global organisation are the by-product of a more localized process of building aggregation. The study concludes that the dualistic structure of these towns and its variation lies in the greater emphasis on male-female relations and the greater localization in the structuring of space. It demonstrates then that the relation between the terrace morphology and the urban form of these towns is shown to exist at the deepest level of space organisation, at the level of the generative rules of settlement formation. By this, the study uses an architectural approach to broach the question of relationship between the social and spatial aspects of these towns.

No description available.

The equilibrium approach to representing interactions between the supply and demand sides of traffic assignment has been used widely in the estimation of traffic flows on road networks. Although this approach is quite reasonable, there is a considerable gap between the observed and modelled values of cost and flow. This gap can be reduced by relaxing some of the restrictive assumptions behind the models used in order to enhance their realism. This study investigates the solutions of various advanced road traffic assignment models. Priority and signal controlled junctions are modelled in traffic assignment in order to enhance the realism of junction analysis. A multiclass assignment is modelled to represent different groups of users. These problems are known to be non-separable because traffic cannot be segmented in such a way that the costs incurred by any one segment vary only with the flow within that segment. Existence, uniqueness and stability properties of solutions to these problems are investigated. These analyses are important to know the reliability and repeatability of any solutions that are calculated. Analyses of these properties lead to some guidelines for using these detailed models. A number of new solution algorithms are developed to solve the resulting traffic assignment problems. These algorithms belong to the general category of simplicial decomposition which solves the problem by dividing it into two subproblems: a linear and a master subproblem which are solved alternately. One of the advantages of these algorithms is that they operate in a lower dimensional space than that of original feasible region and hence allow large-scale problems to be solved with improved accuracy and speed of convergence. These improved algorithms give many choices to the traffic management studies. Two substantial networks have been used to compare the performance of new algorithms on the various models developed. They have performed favourably by comparison with existing algorithms. A small example network has been used to investigate existence, uniqueness and stability properties using the models. In a priority controlled model, a unique stable solution has been obtained using the model whilst in a signal controlled model, multiple and unstable solutions have been obtained. In a multiclass model, a unique solution has been obtained in terms of the total class flow whilst multiple solutions have been obtained in terms of each class flow. These results correspond well to the theoretical analyses of these models, which has shown to have indeterminate behaviour and by the nature of these models assumed, the degree of non-separability is ordered according to priority controlled, multiclass and signal controlled models.

The Palestinian territories have been under foreign military occupation since 1967 and this research is set to examine the implication that this situation has had on the built environment in the historic city of Nablus. Nablus like many other towns and villages in the occupied West Bank has been subject to strict planning policies and regulations controlling development. These policies and regulations restricted its ability to improve its built environment, modernise and expand its service networks, roads and infrastructure, and to accommodate the additional needs arising from the pressure for growth and increase in its population. The purpose of the study therefore, is to examine the built environment in Nablus and identify the indicators for its decline particularly in the city centre. It also aims to establish the main factors that have contributed to the deterioration of its physical condition and the major obstacles to its development. The difficult political conditions and frequent military clashes have had an adverse effect on the built environment and prospects for development. The study findings show that the Israeli occupation authorities have imposed major changes on the institutional structures and legislation that prevailed on the eve of the occupation. The Israeli administration of the occupied Palestinian territories was characterised by the centralisation of power, weakening of local authorities and absence of any form of Palestinian participation in decisions related to development. The study concludes that the planning and regulatory policies imposed by the Israeli Administration during the occupation of Palestine have been a major cause of the deterioration in the built environment in Nablus and suggests that it has had a similar impact on other towns in occupied Palestine.