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In this paper we consider two traffic control strategies relying on user response to information and/or flow restriction. Ultimately, the control strategies are designed to function in real time, hence provide command values based on actual conditions and requiring little computational effort. The proposed control strategies are based on the idea that the network load, as measured by instantaneous travel times for instance, should be shared as equally as possible between paths. In order to achieve such an aim, the commands are designed to make the system state converge towards a state in which instantaneous travel times of paths relative to any given OD tend to be equal.

This paper investigates the temporal inflow profile that minimises the total cost of travel for a single route. The problem is formulated to consider the case in which the total demand to be serviced is fixed. The approach used here is a direct calculation of the first order variation of total system cost with respect to variations in the inflow profile. Two traffic models are considered; the bottleneck with deterministic queue and the kinematic wave model. For the bottleneck model a known solution is recovered. The wave model proves more difficult and after eliminating the possibility of a smooth inflow profile the restricted case of constant inflow is solved. As the space of possible profiles is finite dimensional in this case, the standard techniques of calculus apply. We establish a pair of equations that are satisfied simultaneously by the optimal inflow and time of first departure.

This paper aims to present a linear mathematical framework for modeling and optimizing road transport infrastructure. The framework assesses and optimizes performance of existing transport facility rather than relying on building new roads for the ever-increasing travel demand.

The mathematical framework is built upon a traffic model called Cell Transmission Model (CTM). CTM describes the relationship and evolution of traffic flow and concentration over space and time. The model is parsimonious and accurate in predicting traffic dynamics. More importantly, the traffic flow model is piecewise linear with which the corresponding transport facility optimization problem can be formulated as a Linear Programming (LP) problem and solved by established solution algorithm for global optimality.

We select a section on England Motorway M25 as a case study. With traffic data, we first calibrate the CTM, and we are able to produce traffic estimation with a reasonable error rate of 12 per cent. The corresponding LP then seeks an optimal ramp metering strategy that minimizes the delay on the motorway. It is shown that an optimal and practical strategy can be derived which reduces the motorway delay by 10 per cent without significantly hurting the surrounding connectors.

Instead of the tedious microscopic models used by many traditional tools, the underlying CTM is parsimonious and reliable. The tools developed herein are based upon plausible traffic theory and will be accessible for a wide range of users. The LP formulation can be easily implemented and solved for optimal and practical control strategies for real-world transport networks by using existing computer software (CPLEX) within reasonable computational time. The present work will certainly contribute to the sustainable development of transport facility.

Climate change poses diverse, often fundamental, challenges to livelihoods of island peoples. The purpose of this study is to demonstrate that these challenges must be better understood before effective and sustainable adaptation is possible.

Understanding past livelihood impacts from climate change can help design and operationalize future interventions. In addition, globalization has had uneven effects on island countries/jurisdictions, producing situations especially in archipelagoes where there are significant differences between core and peripheral communities. This approach overcomes the problems that have characterized many recent interventions for climate-change adaptation in island contexts which have resulted in uneven and at best only marginal livelihood improvements in preparedness for future climate change.

Island contexts have a range of unique vulnerability and resilience characteristics that help explain recent and proposed responses to climate change. These include the sensitivity of coastal fringes to climate-environmental changes: and in island societies, the comparatively high degrees of social coherence, closeness to nature and spirituality that are uncommon in western contexts.

Enhanced understanding of island environmental and social contexts, as well as insights from past climate impacts and peripherality, all contribute to more effective and sustainable future interventions for adaptation.

The need for more effective and sustainable adaptation in island contexts is becoming ever more exigent as the pace of twenty-first-century climate change increases.

In a recent issue of the Journal of Applied Behavioral Science, Blake strongly criticised an article on organisational change by Blumberg and Wiener for the authors' failure thoroughly to review the literature and for missing important material relevant to their study. In response, Blumberg simply stated that they were not aware of the material, because it had appeared in a relatively obscure journal. Indeed, a later writer (Zurcher) criticised one of Blake's papers on the same grounds, and then suggested that an event such as this might easily happen to any of us. Despite their apparent conflict, each of these individuals did agree, of course, that a thorough review of the literature on any given topic is necessary to good research and reporting. Our purpose here is not to pour salt on wounds, but rather to illustrate our raison d'être for presenting the material below.