An important objective for train operating companies is to let users, especially commuters, directly query the ICT system about trains’ availability calendar, based on an online approach, and give them clear and brief information, expressed through “intelligent” phrases instead of bit maps. This paper provides a linear programming model of this problem and a fast and flexible heuristic algorithm to create descriptive sentences from train calendars. The algorithmic method, based on the “Divide and Conquer” approach, takes the calendar period queried in its whole and divides it into subsets, which are successively processed one by one. The dominant limitation of previous methods is their strong dependence on the size and complexity of instances. On the contrary, our computational findings show that the proposed online algorithm has a very limited and constant computation time, even when increasing the problem complexity, keeping its processing time between 0 and 16 ms, while producing good quality solutions that differ by an average surplus of 0.13 subsentences compared to benchmark state-of-art solutions.

中文翻译：

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以客户为中心的列车日历生成的线性规划模型和在线算法

列车运营公司的一个重要目标是让用户，尤其是通勤者，基于在线方式，直接向ICT系统查询列车的可用日历，并通过“智能”短语而不是位图向他们提供清晰简洁的信息. 本文提供了该问题的线性规划模型和快速灵活的启发式算法，以从火车日历中创建描述性句子。算法方法基于“分而治之”的方法，将查询到的日历周期整体划分为子集，逐个依次处理。以前方法的主要限制是它们对实例的大小和复杂性的强烈依赖。相反，