In this paper, Johannes Gückel, Teodor Gabriel Crainic, and Pirmin Fontaine examine the rules under which different logistics service providers can cooperate within two-tier city logistics systems. To this end, the authors develop a mixed-integer linear programming model based on a service network design formulation. The model is extended by various fairness constraints that account for both monetary and workload-related aspects.
An extensive numerical study demonstrates that cooperation can lead to substantial cost savings as well as significant reductions in CO₂ emissions. Moreover, the study investigates the additional costs that arise when, beyond minimizing total system costs, additional fairness criteria are imposed to ensure a balanced allocation of costs and workloads among the logistics providers. The results further show that it is considerably more efficient to enforce fairness criteria on average over a longer planning horizon rather than on each individual day.
The findings provide valuable implications for logistics service providers and municipalities aiming to promote sustainable and stable cooperation models in urban logistics.
The article is now available online here.