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The research conducted an Information and Communication Technology (ICT) field survey, the results revealed that Tanzania is still lagging behind in the ICT sector due to the lack of an internationally connected terrestrial ICT infrastructure; Internet connectivity to the rest of the world is via expensive satellite links, thus leaving the majority of the population unable to access the Internet services due to its high cost. Therefore, an ICT backbone infrastructure is designed that exploits optical DWDM network technology, which un-locks bandwidth bottlenecks and provides higher capacity which will provide ICT services such as Internet, voice, videos and other multimedia interactions at an affordable cost to the majority of the people who live in the urban and rural areas of Tanzania. The research analyses and compares the performance, and system impairments, in a DWDM system at data transmission rates of 2.5 Gb/s and 10 Gb/s per wavelength channel. The simulation results show that a data transmission rate of 2.5 Gb/s can be successfully transmitted over a greater distance than 10 Gb/s with minimum system impairments. Also operating at the lower data rate delivers a good system performance for the required ICT services. A forty-channel DWDM system will provide a bandwidth of 100 Gb/s. A cost analysis demonstrates the economic worth of incorporating existing optical fibre installations into an optical DWDM network for the creation of an affordable ICT backbone infrastructure; this approach is compared with building a completely new optical fibre DWDM network or a SONET/SDH network. The results show that the ICT backbone infrastructure built with existing SSMF DWDM network technology is a good investment, in terms of profitability, even if the Internet charges are reduced to half current rates. The case for building a completely new optical fibre DWDM network or a SONET/SDH network is difficult to justify using current financial data.

In this research, we present a theoretical and computational framework for studying the vehicle routing problem with uncertain demands (VRPUD). We combine approaches in stochastic optimization and techniques in mixed integer programming to solve two main variants of the vehicle routing problem with uncertain demands. We first present a polyhedral study for deterministic heterogenous vehicle routing problems (HVRP) to develop a relatively efficient formulation such that its corresponding counterpart with uncertainty is tractable via mixed integer programming. Having assumed customers’ demand is uncertain, we apply three single-stage approaches within stochastic optimization to the HVRP with uncertain demands. The three-single stage approaches are chance constrained programming, Ben-Tal and Nemirovski, and Bertsimas and Sim robust optimization approaches. Then, we plug the corresponding formulation for each approach into a branch-and-cut method. Moreover, we propose a new framework within the branch-and-price framework to formulate the capacitated vehicle routing problem (CVRP) with uncertain demands. In addition to the three single-stage approaches, we apply a two-stage stochastic approach to the capacitated vehicle routing problem with uncertain demands. Our proposed framework enables us to model di↵erent types of uncertainty while the complexity of the resulting problem remains the same. Finally, we present extensive computational experiments for the deterministic HVRP, the HVRP with uncertain demands and the CVRP with uncertain demands. In the computational experiments we first investigate efficiency of several types of valid inequalities and lifting techniques for the deterministic HVRP. Then, using simulation and a scenario based technique we assess the performance, advantages and disadvantages of the aforementioned stochastic optimization approaches for the HVRP with uncertain demands and the CVRP with uncertain demands. We show that among single-stage approaches of stochastic optimization, those with control parameters outperform those without control parameters in terms of total expected cost. Also, we show that the higher protection level does not necessarily result in better solutions as higher protection levels may impose unnecessary extra costs. Moreover, as our computational experiments suggest, the two-stage models for the CVRP dominate the single-stage approaches for all protection level scenarios.

This thesis justifies, designs and tests a new transport appraisal technique – the Transport Quality of Life (TQoL) model. In the United Kingdom the New Approach to Transport Appraisal (NATA) is presently used to appraise the economic, environmental and social impacts of transport projects. Although recently updated, NATA still does not include the assessment of individual’s travel experience – and yet, to make fully informed decisions on the impact of future schemes, it is important to understand more about passenger’s current journey quality. This thesis thus explores the potential of Quality of life (QoL) techniques as one means of addressing this gap in appraisal methods and scope. For the purposes of this thesis, TQoL is defined as the passenger experience of travel. Through the thesis a TQoL model was progressively refined and developed –from an initial Mark I model to a more evolved and developed Mark III model - to produce an appraisal tool that highlights differences in journey experience. To develop the model and to determine whether a TQoL approach was a valuable addition to transport appraisal, QoL techniques were applied to the transport networks of Glasgow and Manchester. In each city three modes of public transport were analysed to identify the mode providing the highest TQoL. A two-part household survey was used to gather data. The first survey was city-wide to gain the weightings for the TQoL indicators. The second was collected from selected transport corridors to evaluate TQoL. The results were quantified and presented in spider diagrams. T-tests were then used to identify the significant differences in TQoL. Factor analysis on the data from both Glasgow and Manchester showed that a TQoL model can be based on five factors - access and availability, sustainable transit, environment, personal safety and transport costs. Applying the final TQoL model showed that in both locations fixed modes - particularly Light Rapid Transport - provide a significantly higher TQoL compared to bus TQoL. By evaluating transport from the passenger’s viewpoint, the TQoL model can make transport appraisal more comprehensive. The thesis therefore concludes that the TQoL model should be used to supplement existing techniques to enable policy makers and practitioners make better informed decisions about improving the quality of transport.

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This thesis explores the impacts of geographical structures of local governance upon the development of passenger rail transport policies in the Merseyside and Strathclyde urban regions. Rather than evaluate policy outcomes, it describes and analyses the systems and processes through which strategic rail transport policy-making is shaped and constrained. The impacts upon urban local rail transport policy-making of the statutory Passenger Transport Authorities and Executives, other local authorities, public and private sector bodies and individuals, which together comprise the prevailing structure of local governance in each area, are traced. The theory of the urban policy regime is applied to explain the development of particular policies from their basis in local political and popular concern, through to their implementation or rejection in order to illustrate the influences of each member of the policy community in practice. The two study areas and 1986-1996 timescale are chosen to represent the period when two differing territorial structures of Passenger Transport Authority (PTA) co-existed in the UK. Strathclyde Regional Council, which acted as PTA for the Clydeside conurbation and surrounding area in the west of Scotland, was the last remaining example in the UK of a strategic urban local government with jurisdiction over an entire city-region. In contrast, Merseytravel, the PTA responsible for local rail transport development in Merseyside, an urban region of similar economic, social and rail transport structure to Strathclyde, was jointly administered by five smaller local authorities acting under the quasi-market principles of public choice theory. Through a detailed exposition of the development of urban rail transport policies in each area, the ways in which both types of institutional arrangement influenced the structure and operation of the local policy regime, and its pattern of policy discourse, are analysed. The opportunities arising for the effective expression of public accountability under each system are highlighted, since this is a central aspiration of the abolition of strategic city-region wide local authorities inspired by public choice theory.

This thesis looks at the politics of transport in the Major era, arguing that transport has emerged as an issue of high political salience in the 1990s. In this period transport, and most particularly the motor car, increasingly came to be blamed for a combination of economic and environmental problems including rising congestion, noise, land-use impacts and a deterioration of air quality and traffic safety standards. The primary. aim of this thesis is to explain these developments and their effects by utilising agenda setting theory. This thesis argues that the operation of the agenda setting dynamic in the transport case illustrates aspects of a number of models of agenda setting. It looks at the role of actors, problems, external events and non-decision making and argues that, in part, they all make a useful contribution to the study of political change in the Major era. However, it also argues that different models of agenda setting apply in different circumstances and that a model which may provide a useful explanation of situation A may provide a less satisfactory explanation of situation B. The explanation for this is that transport is a multi-faceted issue which affects mobility, the environment, and economic development as well as issues of lifestyle and personal freedom; the priorities which central government attaches to transport policy outcomes reflect this diversity. These different aspects of the transport issue are affected by different agenda setting processes, depending on the extent to which they challenge the dominant policy imperatives of the state. For example, in a situation in which the policy imperatives of the state are threatened, the agenda setting process will be highly constrained and proponents of change, will find it very difficult, if not impossible, to alter the agenda. In such a case, the models of non-decision making will be an important, often the dominant, explanation of the agenda setting process. Overall, this study argues that the transport agenda setting process operates in, and is constrained by, a policy making environment which is dominated by the policy imperatives of the state.

This work studies three related topics arising from the problem of forecasting airline passenger bookings. The first topic concerns the initialization through the starting prior for a DLM (Dynamic Linear Model) or Generalized DLM. An approach is given which uses the first observations of the series much more efficiently than that suggested by Pole and West. Proper marginal priors are derived for stationary model components and proper marginal priors may be obtained for parameter subspaces and used for forecasting within that subspace well before a full proper prior is available. The second topic proposes a model to forecast the number of people booking tickets for particular flights. The model is more realistic than those which are classically used, since it is a dynamic model and acknowledges discrete distributions. The basic idea is given by the Dynamic Generalized Linear Model and a key feature is given by the gamma to log-normal approximation that is developed. The third topic consists of a study of temporal aggregation of a process that can be represented by a DLM. We give representation results for the simplest univariate cases, reveal some surprising phenomena, such as drastic model simplification with aggregation, and discuss some advantages and disadvantages of using the aggregated observations, depending on the forecasting objectives, as well as the importance of aggregation in our particular booking problem.

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