@misc{EulerBorndoerferStrunketal.2021, author = {Euler, Ricardo and Bornd{\"o}rfer, Ralf and Strunk, Timo and Takkula, Tuomo}, title = {ULD Build-Up Scheduling with Dynamic Batching in an Air Freight Hub}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-83482}, year = {2021}, abstract = {Air freight is usually shipped in standardized unit load devices (ULDs). The planning process for the consolidation of transit cargo from inbound flights or locally emerging shipments into ULDs for outbound flights is called build-up scheduling. More specifically, outbound ULDs must be assigned a time and a workstation subject to both workstation capacity constraints and the availability of shipments which in turn depends on break-down decisions for incoming ULDs. ULDs scheduled for the same outbound flight should be built up in temporal and spatial proximity. This serves both to minimize overhead in transportation times and to allow workers to move freight between ULDs. We propose to address this requirement by processing ULDs for the same outbound flight in batches. For the above build-up scheduling problem, we introduce a multi-commodity network design model. Outbound flights are modeled as commodities; transit cargo is represented by cargo flow volume and unpack and batch decisions are represented as design variables. The model is solved with standard MIP solvers on a set of benchmark data. For instances with a limited number of resource conflicts, near-optimal solutions are found in under two hours for a whole week of operations.}, language = {en} } @article{BorndoerferEulerKarbstein2021, author = {Bornd{\"o}rfer, Ralf and Euler, Ricardo and Karbstein, Marika}, title = {Ein Graphen-basiertes Modell zur Beschreibung von Preissystemen im {\"o}ffentlichen Nahverkehr}, volume = {002/127}, journal = {HEUREKA 21}, publisher = {FGSV}, address = {Stuttgart}, pages = {1 -- 15}, year = {2021}, abstract = {In dieser Arbeit wird ein graphenbasiertes Modell zur Einbindung von Preissystemen des {\"o}ffentlichen Nahverkehrs in Routing-Algorithmen vorgestellt. Jeder Knoten des Graphen repr{\"a}sentiert einen abstrakten Preiszustand einer Route und ist an einen tats{\"a}chlichen Preis gekoppelt. Damit sind sehr einfache und konzise Beschreibungen von Tarifstrukturen m{\"o}glich, diesich algorithmisch behandeln lassen. Durch das zeitgleiche Tracken eines Pfades im Routinggraphen im Ticketgraphen kann schon w{\"a}hrend einer Routenberechnung der Preis bestimmt werden. Dies erm{\"o}glicht die Berechnung von preisoptimalen Routen. An den Tarifsystemen der Verkehrsverb{\"u}nde MDV (Mitteldeutscher Verkehrsverbund) und VBB (Verkehrsverbund Berlin-Brandenburg) wird die Konstruktion des Modells detailliert erl{\"a}utert.}, language = {de} }