TY - JOUR A1 - Gotzes, Uwe A1 - Gotzes, Claudia T1 - The Jeep Problem: A Flexible MIP Formulation JF - Journal of Nepal Mathematical Society N2 - This article deals with the Jeep Problem (also known as Desert Crossing Problem), which reads as follows: An unlimited supply of fuel is available at one edge of a desert, but there is no source on the desert itself. A vehicle can carry enough fuel to go a certain distance, and it can built up its own refuelling stations. What is the minimum amount of fuel the vehicle will require in order to cross the desert? Under these mild conditions this question is answered since the 1940s. But what is the answer if the caches are restricted to certain areas or if the fuel consumption does not depend linearly on the distance travelled? To answer these and similar questions we develop and solve a flexible mixed-integer programming (MIP) model for the classical problem and enhance it with new further aspects of practical relevance. Y1 - 2018 SN - 2616-0161 VL - 1 SP - 11 EP - 17 ER - TY - GEN A1 - Gotzes, Uwe A1 - Hoppmann, Kai T1 - Bounds for the final ranks during a round robin tournament T2 - Operational Research - An International Journal (ORIJ) N2 - This article answers two kinds of questions regarding the Bundesliga which is Germany's primary football (soccer) competition having the highest average stadium attendance worldwide. First "At any point of the season, what final rank will a certain team definitely reach?" and second "At any point of the season, what final rank can a certain team at most reach?". Although we focus especially on the Bundesliga, the models that we use to answer the two questions can easily be adopted to league systems that are similar to that of the Bundesliga. T3 - ZIB-Report - 19-50 Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-74638 ER - TY - GEN A1 - Hoppmann, Kai A1 - Hennings, Felix A1 - Lenz, Ralf A1 - Gotzes, Uwe A1 - Heinecke, Nina A1 - Spreckelsen, Klaus A1 - Koch, Thorsten T1 - Optimal Operation of Transient Gas Transport Networks T3 - ZIB-Report - 19-23 Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-73639 SN - 1438-0064 ER -