The BusPlus project aims at improving the off-peak hours public transit service in Canberra, Australia.To address the difficulty of covering a large geographic area, BusPlus proposes a hub and shuttle model consisting of a combination of a few high-frequency bus routes between key hubs and a large number of shuttles that bring passengers from their origin to the closest hub and take them from their last bus stop to their destination. This paper focuses on the design of bus network and proposes an efficient solving method to this multimodal network design problem based on the Benders decomposition method. Starting from a MIP formulation of the problem, the paper presents a Benders decomposition approach using dedicated solution techniques for solving independent sub-problems, Pareto optimal cuts, cut bundling, and core point update.Computational results on real-world data from Canberra's public transit system justify the design choices and show that the approach outperforms the MIP formulation by two orders of magnitude. Moreover, the results show that the hub and shuttle model may decrease transit time by a factor of 2, while staying within the costs of the existing transit system.

We consider the design and implementation of a centralised oracle that provides commuters with customised and congestion-aware driving directions. Computing directions for a single journey is straightforward, but doing so at city-scale, in real-time, and under changing conditions is extremely challenging. In this work we describe a new type of centralised oracle which combines fast database-driven path planning with a query management system that distributes work across a small commodity cluster of networked machines. Our system allows large-scale changes to the underlying graph metric, from one query to the next, and it supports a variety of query types including optimal, bounded suboptimal, time-budgeted and k-prefix. Simulated experiments show strong results: we can provide real-time routing for all peak-hour commuter trips in the city of Melbourne, Australia.

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The volume of historical purchasing data has become huge, and it includes many kinds of data attributes.Specifically, categorical data, such as product codes, are diffi cult to handle. If the product is purchased repeatedly, we can aggregate the data and use the product data as a numerical attribute. However, if the item was purchased only once, we can get only very basic information, such as whether it was purchased or not. To use the information more effectively, we can use a subset of these purchased items as a purchasing pattern within the set of items. Some classification predictive models that use these patterns were proposed, including the classification by aggregating contrast patterns (CACP). How ever, the model sometimes produces too many specific patterns. This is not a problem for predictions, but interpreting the model can become too complicated to implement efficiently.In this paper, we propose a method to decrease the number of patterns in the classification model for CACP. The proposed method uses the meta-heuristics algorithm known as greedy randomized adaptive search procedure (GRASP). A computa tional experiment shows that we can remove extra patterns and construct the model, while maintaining its performance level.