around 30 percent between MegaHub and Lübeck Skandinavienkai (and v.v.). Delays can be caused by various factors, including technical failures, constructions, road- blocks, staff shortages, and delays caused by previous delays. Due to critical delays, simultaneous train arrivals are frequently impossible, implying that planned connec- tions are no longer available. In such cases, arriving trains must choose between two scenarios: waiting, which causes further delays, and departing on time, which causes container backlogs at the hubs. d. Semi-automated sorting system MegaHub’s sorting system consists of semi- automated gantry cranes and AGVs between inbound and outbound tracks, with an annual transshipment capacity of 269,000 LUs [23]. Most LUs were directly handled by cranes and AGVs, and some stacking posi- tions also stand in the crane’s operating area for temporary parking. This sorting system is supported by a special operation control system, which aims to minimize energy consumption and wear. It directs AGVs to automatically deliver LUs to the designated wagon, avoiding unnecessary crane move- ment, and optimizing the operation path and brake process between crane positions to achieve energy efficiency. However, the position selection decision is completed by crane drivers, this operation control system only provides suggestions of open positions for handling. Conclusion Through the literature-based and real- world case studies, we found that the bun- dling on a rail-based Hub-and-Spoke net- work revolves around two main points: syn- chronization and traffic imbalance. The trains on the HS network need to arrive at the hub as synchronized as possible, and the transshipment must be completed in a short time, which puts more pressure on the schedule bundling and the sorting process, as well as makes the trains being more sensi- tive to time delays. 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DB. https://gruen.deutschebahn.com/en/measures/megahub Ralf Elbert, Prof. Dr. Professor, Chair of Management and Logistics, TU Darmstadt (DE) elbert@log.tu-darmstadt.de Hongjun Wu, M.Sc. Research Associate, Chair of Management and Logistics, TU Darmstadt (DE) wu@log.tu-darmstadt.de Let’s keep in touch editorsdesk@international-transportation.com advertising@international-transportation.com Trialog Publishers Verlagsgesellschaft | Schliffkopfstrasse 22 | D-72270 Baiersbronn Tel.: +49 7449 91386.36 | Fax: +49 7449 91386.37 | office@trialog.de | www.trialog-publishers.de Internationales Verkehrswesen (74) 3 | 2022 61