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Low-income countries (LICs) in Sub-Saharan Africa and South Asia are investing in new railway lines to replace deteriorated infrastructure from the 19th and 20th century. These actions, despite financial and economic constraints, have been justified in common visions of continent-wide efficient networks to cope with the demands of growing populations. However, most of the recent rail infrastructure projects are driven by international suppliers’ preferences and financing rather than creating railways that match the requirements of interoperable regional networks. This paper therefore explores the current status of rail infrastructure in these LICs and the operational performance achieved to understand specific capability gaps in each regional network. Drawing from the experience of European countries in transforming regional future visions into applied research, a technical strategy for rail infrastructure in LICs is proposed. The strategy captures the key capabilities to be addressed in order to achieve future performance goals, while emphasizing the need for emerging technologies to be used in fit-for-purpose solutions. It is envisioned that the strategy will provide the basis for the development of continental technical strategy programs with specific technology roadmaps towards a common goal.

Background Despite their important role in railway operations, switches and crossings (S&C) have changed little since their conception over a century ago. It stands now that the existing designs for S&C are reaching their maximum point of incremental performance improvement, and only a radical redesign can overcome the constraints that current designs are imposing on railway network capacity. This paper describes the process of producing novel designs for next generation switches and crossings, as part of the S-CODE project. Methods Given the many aspects that govern a successful S&C design, it is critical to adopt multi criteria decision making (MCDM) processes to identify a specific solution for the next generation of switches and crossings. However, a common shortcoming of these methods is that their results can be heavily influenced by external factors, such as uncertainty in criterium weighting or bias of the evaluators, for example. This paper therefore proposes a process based on the Pugh Matrix method to reduce such biases by using sensitivity analysis to investigate them and improve the reliability of decision making. Results In this paper, we analysed the influences of three different external factors, measuring the sensitivity of ranking due to (a) weightings, (b) organisational and (c) discipline bias. The order of preference of the results was disturbed only to a minimum while small influences of bias were detected. Conclusions Through this case study, we believe that the paper demonstrates an effective case study for a quantitative process that can improve the reliability of decision making.

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The significant growth in the size of cities has led to an increase in distances travelled that emphasises the systemic shortcomings of metros. Metro systems are hindered by a paradox between the time to access stations and the average speed on the line, which prevents them from offering competitive door-to-door speeds within the natural time budgets of users. The authors present a novel methodology that combines the back-casting method with a systems engineering approach to develop a robust problem-solving process that can cope with the uncertainty of future scenarios. The approach has been used to develop a solution to the paradox, that is based on an operational strategy where autonomous vehicles stop in different patterns at stations along a line. It is proposed that vehicles will travel in platoons and be controlled by vehicle-to-vehicle communication algorithms similarly to those in automated highways. Simulations show that this strategy can increase the average speed on a line by 129%, reducing door-to-door journey times by up to 45%, compared to conventional operations. Moreover, capacity is increased by 30% within conventional platform lengths. In conclusion, this process can lead to solutions that accommodate future demands and change current trends into more desirable futures.