Abstract Less-than-truckload (LTL) freight transportation is a vital part of Canada’s economy, with revenues running into billions of dollars and a cascading impact on many other industries. LTL operators have to deal with large volumes of shipments and uncertainty in demand patterns. In an industry that already has low profit margins, it is therefore vitally important to make good quality routing decisions without expending a lot of time. The optimization of such LTL freight networks results in large scale mathematical programming problems. In this paper, we present a novel Integer Linear Programming (ILP) formulation and heuristics for routing LTL freight. Experiments in collaboration with our industry partner indicate that our proposals can significantly lower routing costs for Canadian LTL operators. In addition, our approach can be useful for generating load plans on larger American LTL networks.

中文翻译：

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整数规划模型和基于 Steiner-forest 的启发式算法，用于路由零担货物

摘要 零担 (LTL) 货运是加拿大经济的重要组成部分，收入高达数十亿美元，并对许多其他行业产生连锁影响。零担运输运营商必须处理大量运输和需求模式的不确定性。在一个利润率已经很低的行业中，因此在不花费大量时间的情况下做出高质量的路由决策至关重要。这种 LTL 货运网络的优化会导致大规模的数学规划问题。在本文中，我们提出了一种新颖的整数线性规划 (ILP) 公式和启发式方法，用于路由 LTL 货运。与我们的行业合作伙伴合作的实验表明，我们的建议可以显着降低加拿大 LTL 运营商的路线成本。此外，