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Bike-sharing schemes (BSSs) have gained popularity as an alternative mode of transportation to solve the first/last mile problem. However, the bike-share market is subject to an oversupply problem with a low fleet utilisation rate in many countries. The aim of this paper is to tackle the BSS optimisation problem under stochastic demand scenarios by determining the shared bicycle fleet size and a fleet deployment strategy, where the interests of multiple stakeholders are taken into consideration at the same time. A stochastic multi-period bi-objective optimisation model is formulated to maximise the profit of bike-share operators and minimise the unmet demand, controlling the bike fleet utilisation rate. The problem is solved by an augmented ε-constraint method (Augmecon), which generates a set of non-dominated solutions. The numerical test is conducted with real data from Citi Bike to evaluate the validity of the model formulation and the effectiveness of the solution algorithm. The effect of fleet utilisation rate on BSS is analysed, where the trade-offs among earned profit, service level and fleet utilisation rate are addressed. [ABSTRACT FROM AUTHOR]

Fluctuations in traffic flows at isolated intersections throughout the day have a negative impact on the control effects of certain traffic signal control methods. To solve this problem, adaptive signal control of isolated intersections based on sequential signal-stage optimisation is proposed under a multi-stage optimal decision framework to reduce vehicle delays and increase traffic efficiency. In this paper, to maximise the traffic capacity of an intersection during a signal stage, a primary and secondary control mechanism is designed in which the signal-stage phase (SSP) is composed of primary and secondary compatible phases. The SSP can be dynamically obtained and its maximum duration can be determined in a predictable manner. The terminal conditions are also designed to end the current SSP in a timely manner to increase the traffic throughput of an isolated intersection during a signal cycle. For easier understanding, the adaptive signal control algorithm is elaborated in detail. Numerous simulation experiments were performed in the Vissim 5.4 software program and the simulation results demonstrated that, compared with fixed timing control, segmented timing control and fully actuated control, the proposed control method can clearly reduce the average vehicle delay and the impact on average vehicle stops is acceptable. [ABSTRACT FROM AUTHOR]

This paper presents the application of the multicriteria decision-making methods ELECTRE-I and AHP to a layout alternatives decision for a new high-speed train for the Madrid-Valencia high-speed line. The official choice is presented as a first introduction with the planning decision of the corresponding new high-speed lines for the south-east of Spain as part of the 2002-2007 high-speed network plan for Spain. This official selection of layout alternatives was decided in January 2002. The data used by the authors were obtained from public reports and official surveys, including two cost-effectiveness studies in net present value format for that part of the network that includes the important link between Madrid and Valencia. A short analysis of these net present value studies follows, and these studies show the feasibility of that part of the network, but were not decisive for the decision of the layout choice. The selection of alternatives for the Madrid-Valencia corridor is academically considered first with an ELECTRE-I method, and then with an analytic hierarchic process method. This is followed by an analysis of the problems using compromise programming. With both multicriteria decision-making methods the results showed that the North option was preferable, or `outranked' the others, in agreement with the official selection. Thus it demonstrates that such methods are appropriate as aids for such decision-making procedures. [ABSTRACT FROM AUTHOR]