TY - CHAP A1 - Weinhold, Carsten A1 - Lackorzynski, Adam A1 - Bierbaum, Jan A1 - Küttler, Martin A1 - Planeta, Maksym A1 - Weisbach, Hannes A1 - Hille, Matthias A1 - Härtig, Hermann A1 - Margolin, Alexander A1 - Sharf, Dror A1 - Levy, Ely A1 - Gak, Pavel A1 - Barak, Amnon A1 - Gholami, Masoud A1 - Schintke, Florian A1 - Schütt, Thorsten A1 - Reinefeld, Alexander A1 - Lieber, Matthias A1 - Nagel, Wolfgang T1 - FFMK: A Fast and Fault-Tolerant Microkernel-Based System for Exascale Computing T2 - Software for Exascale Computing - SPPEXA 2016-2019 Y1 - 2019 U6 - https://doi.org/10.1007/978-3-030-47956-5_16 SP - 483 EP - 516 PB - Springer ER - TY - JOUR A1 - Enke, Harry A1 - Steinmetz, Matthias A1 - Adorf, Hans-Martin A1 - Beck-Ratzka, Alexander A1 - Breitling, Frank A1 - Brüsemeister, Thomas A1 - Carlson, Arthur A1 - Ensslin, Torsten A1 - Högqvist, Mikael A1 - Nickelt, Iliya A1 - Radke, Thomas A1 - Reinefeld, Alexander A1 - Reiser, Angelika A1 - Scholl, Tobias A1 - Spurzem, Rainer A1 - Steinacker, Jürgen A1 - Voges, Wolfgang A1 - Wambsganß, Joachim A1 - White, Steve T1 - AstroGrid-D: Grid technology for astronomical science JF - New Astronomy Y1 - 2011 UR - http://www.sciencedirect.com/science/article/pii/S1384107610000837 U6 - https://doi.org/10.1016/j.newast.2010.07.005 VL - 16 IS - 2 SP - 79 EP - 93 ER - TY - JOUR A1 - Sekuboyina, Anjany A1 - Bayat, Amirhossein A1 - Husseini, Malek E. A1 - Löffler, Maximilian A1 - Li, Hongwei A1 - Tetteh, Giles A1 - Kukačka, Jan A1 - Payer, Christian A1 - Štern, Darko A1 - Urschler, Martin A1 - Chen, Maodong A1 - Cheng, Dalong A1 - Lessmann, Nikolas A1 - Hu, Yujin A1 - Wang, Tianfu A1 - Yang, Dong A1 - Xu, Daguang A1 - Ambellan, Felix A1 - Amiranashvili, Tamaz A1 - Ehlke, Moritz A1 - Lamecker, Hans A1 - Lehnert, Sebastian A1 - Lirio, Marilia A1 - de Olaguer, Nicolás Pérez A1 - Ramm, Heiko A1 - Sahu, Manish A1 - Tack, Alexander A1 - Zachow, Stefan A1 - Jiang, Tao A1 - Ma, Xinjun A1 - Angerman, Christoph A1 - Wang, Xin A1 - Wei, Qingyue A1 - Brown, Kevin A1 - Wolf, Matthias A1 - Kirszenberg, Alexandre A1 - Puybareau, Élodie A1 - Valentinitsch, Alexander A1 - Rempfler, Markus A1 - Menze, Björn H. A1 - Kirschke, Jan S. T1 - VerSe: A Vertebrae Labelling and Segmentation Benchmark for Multi-detector CT Images JF - arXiv Y1 - 2020 ER - TY - JOUR A1 - Schimunek, Johannes A1 - Seidl, Philipp A1 - Elez, Katarina A1 - Hempel, Tim A1 - Le, Tuan A1 - Noé, Frank A1 - Olsson, Simon A1 - Raich, Lluís A1 - Winter, Robin A1 - Gokcan, Hatice A1 - Gusev, Filipp A1 - Gutkin, Evgeny M. A1 - Isayev, Olexandr A1 - Kurnikova, Maria G. A1 - Narangoda, Chamali H. A1 - Zubatyuk, Roman A1 - Bosko, Ivan P. A1 - Furs, Konstantin V. A1 - Karpenko, Anna D. A1 - Kornoushenko, Yury V. A1 - Shuldau, Mikita A1 - Yushkevich, Artsemi A1 - Benabderrahmane, Mohammed B. A1 - Bousquet-Melou, Patrick A1 - Bureau, Ronan A1 - Charton, Beatrice A1 - Cirou, Bertrand C. A1 - Gil, Gérard A1 - Allen, William J. A1 - Sirimulla, Suman A1 - Watowich, Stanley A1 - Antonopoulos, Nick A1 - Epitropakis, Nikolaos A1 - Krasoulis, Agamemnon A1 - Itsikalis, Vassilis A1 - Theodorakis, Stavros A1 - Kozlovskii, Igor A1 - Maliutin, Anton A1 - Medvedev, Alexander A1 - Popov, Petr A1 - Zaretckii, Mark A1 - Eghbal-Zadeh, Hamid A1 - Halmich, Christina A1 - Hochreiter, Sepp A1 - Mayr, Andreas A1 - Ruch, Peter A1 - Widrich, Michael A1 - Berenger, Francois A1 - Kumar, Ashutosh A1 - Yamanishi, Yoshihiro A1 - Zhang, Kam Y. J. A1 - Bengio, Emmanuel A1 - Bengio, Yoshua A1 - Jain, Moksh J. A1 - Korablyov, Maksym A1 - Liu, Cheng-Hao A1 - Marcou, Gilles A1 - Glaab, Enrico A1 - Barnsley, Kelly A1 - Iyengar, Suhasini M. A1 - Ondrechen, Mary Jo A1 - Haupt, V. Joachim A1 - Kaiser, Florian A1 - Schroeder, Michael A1 - Pugliese, Luisa A1 - Albani, Simone A1 - Athanasiou, Christina A1 - Beccari, Andrea A1 - Carloni, Paolo A1 - D’Arrigo, Giulia A1 - Gianquinto, Eleonora A1 - Goßen, Jonas A1 - Hanke, Anton A1 - Joseph, Benjamin P. A1 - Kokh, Daria B. A1 - Kovachka, Sandra A1 - Manelfi, Candida A1 - Mukherjee, Goutam A1 - Muñiz-Chicharro, Abraham A1 - Musiani, Francesco A1 - Nunes-Alves, Ariane A1 - Paiardi, Giulia A1 - Rossetti, Giulia A1 - Sadiq, S. Kashif A1 - Spyrakis, Francesca A1 - Talarico, Carmine A1 - Tsengenes, Alexandros A1 - Wade, Rebecca C. A1 - Copeland, Conner A1 - Gaiser, Jeremiah A1 - Olson, Daniel R. A1 - Roy, Amitava A1 - Venkatraman, Vishwesh A1 - Wheeler, Travis J. A1 - Arthanari, Haribabu A1 - Blaschitz, Klara A1 - Cespugli, Marco A1 - Durmaz, Vedat A1 - Fackeldey, Konstantin A1 - Fischer, Patrick D. A1 - Gorgulla, Christoph A1 - Gruber, Christian A1 - Gruber, Karl A1 - Hetmann, Michael A1 - Kinney, Jamie E. A1 - Padmanabha Das, Krishna M. A1 - Pandita, Shreya A1 - Singh, Amit A1 - Steinkellner, Georg A1 - Tesseyre, Guilhem A1 - Wagner, Gerhard A1 - Wang, Zi-Fu A1 - Yust, Ryan J. A1 - Druzhilovskiy, Dmitry S. A1 - Filimonov, Dmitry A. A1 - Pogodin, Pavel V. A1 - Poroikov, Vladimir A1 - Rudik, Anastassia V. A1 - Stolbov, Leonid A. A1 - Veselovsky, Alexander V. A1 - De Rosa, Maria A1 - De Simone, Giada A1 - Gulotta, Maria R. A1 - Lombino, Jessica A1 - Mekni, Nedra A1 - Perricone, Ugo A1 - Casini, Arturo A1 - Embree, Amanda A1 - Gordon, D. Benjamin A1 - Lei, David A1 - Pratt, Katelin A1 - Voigt, Christopher A. A1 - Chen, Kuang-Yu A1 - Jacob, Yves A1 - Krischuns, Tim A1 - Lafaye, Pierre A1 - Zettor, Agnès A1 - Rodríguez, M. Luis A1 - White, Kris M. A1 - Fearon, Daren A1 - Von Delft, Frank A1 - Walsh, Martin A. A1 - Horvath, Dragos A1 - Brooks III, Charles L. A1 - Falsafi, Babak A1 - Ford, Bryan A1 - García-Sastre, Adolfo A1 - Yup Lee, Sang A1 - Naffakh, Nadia A1 - Varnek, Alexandre A1 - Klambauer, Günter A1 - Hermans, Thomas M. T1 - A community effort in SARS-CoV-2 drug discovery JF - Molecular Informatics KW - COVID-19 KW - drug discovery KW - machine learning KW - SARS-CoV-2 Y1 - 2023 U6 - https://doi.org/https://doi.org/10.1002/minf.202300262 VL - 43 IS - 1 SP - e202300262 ER - TY - JOUR A1 - Lützkendorf, Janine A1 - Matkovic-Rachid, Tanja A1 - Liu, Sunbin A1 - Götz, Torsten A1 - Gao, Lili A1 - Turrel, Oriane A1 - Maglione, Marta A1 - Grieger, Melanie A1 - Putignano, Sabrina A1 - Ramesh, Niraja A1 - Ghelani, Tina A1 - Neumann, Alexander A1 - Gimber, Niclas A1 - Schmoranzer, Jan A1 - Stawrakakis, Anastasia A1 - Brence, Blaž A1 - Baum, Daniel A1 - Ludwig, Kai A1 - Heine, Martin A1 - Mielke, Thorsten A1 - Liu, Fan A1 - Walter, Alexander A1 - Wahl, Markus A1 - Sigrist, Stephan T1 - Blobby is a synaptic active zone assembly protein required for memory in Drosophila JF - Nature Communications Y1 - 2025 U6 - https://doi.org/10.1038/s41467-024-55382-9 VL - 16 ER - TY - JOUR A1 - Sekuboyina, Anjany A1 - Husseini, Malek E. A1 - Bayat, Amirhossein A1 - Löffler, Maximilian A1 - Liebl, Hans A1 - Li, Hongwei A1 - Tetteh, Giles A1 - Kukačka, Jan A1 - Payer, Christian A1 - Štern, Darko A1 - Urschler, Martin A1 - Chen, Maodong A1 - Cheng, Dalong A1 - Lessmann, Nikolas A1 - Hu, Yujin A1 - Wang, Tianfu A1 - Yang, Dong A1 - Xu, Daguang A1 - Ambellan, Felix A1 - Amiranashvili, Tamaz A1 - Ehlke, Moritz A1 - Lamecker, Hans A1 - Lehnert, Sebastian A1 - Lirio, Marilia A1 - de Olaguer, Nicolás Pérez A1 - Ramm, Heiko A1 - Sahu, Manish A1 - Tack, Alexander A1 - Zachow, Stefan A1 - Jiang, Tao A1 - Ma, Xinjun A1 - Angerman, Christoph A1 - Wang, Xin A1 - Brown, Kevin A1 - Kirszenberg, Alexandre A1 - Puybareau, Élodie A1 - Chen, Di A1 - Bai, Yiwei A1 - Rapazzo, Brandon H. A1 - Yeah, Timyoas A1 - Zhang, Amber A1 - Xu, Shangliang A1 - Hou, Feng A1 - He, Zhiqiang A1 - Zeng, Chan A1 - Xiangshang, Zheng A1 - Liming, Xu A1 - Netherton, Tucker J. A1 - Mumme, Raymond P. A1 - Court, Laurence E. A1 - Huang, Zixun A1 - He, Chenhang A1 - Wang, Li-Wen A1 - Ling, Sai Ho A1 - Huynh, Lê Duy A1 - Boutry, Nicolas A1 - Jakubicek, Roman A1 - Chmelik, Jiri A1 - Mulay, Supriti A1 - Sivaprakasam, Mohanasankar A1 - Paetzold, Johannes C. A1 - Shit, Suprosanna A1 - Ezhov, Ivan A1 - Wiestler, Benedikt A1 - Glocker, Ben A1 - Valentinitsch, Alexander A1 - Rempfler, Markus A1 - Menze, Björn H. A1 - Kirschke, Jan S. T1 - VerSe: A Vertebrae labelling and segmentation benchmark for multi-detector CT images JF - Medical Image Analysis N2 - Vertebral labelling and segmentation are two fundamental tasks in an automated spine processing pipeline. Reliable and accurate processing of spine images is expected to benefit clinical decision support systems for diagnosis, surgery planning, and population-based analysis of spine and bone health. However, designing automated algorithms for spine processing is challenging predominantly due to considerable variations in anatomy and acquisition protocols and due to a severe shortage of publicly available data. Addressing these limitations, the Large Scale Vertebrae Segmentation Challenge (VerSe) was organised in conjunction with the International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) in 2019 and 2020, with a call for algorithms tackling the labelling and segmentation of vertebrae. Two datasets containing a total of 374 multi-detector CT scans from 355 patients were prepared and 4505 vertebrae have individually been annotated at voxel level by a human-machine hybrid algorithm (https://osf.io/nqjyw/, https://osf.io/t98fz/). A total of 25 algorithms were benchmarked on these datasets. In this work, we present the results of this evaluation and further investigate the performance variation at the vertebra level, scan level, and different fields of view. We also evaluate the generalisability of the approaches to an implicit domain shift in data by evaluating the top-performing algorithms of one challenge iteration on data from the other iteration. The principal takeaway from VerSe: the performance of an algorithm in labelling and segmenting a spine scan hinges on its ability to correctly identify vertebrae in cases of rare anatomical variations. The VerSe content and code can be accessed at: https://github.com/anjany/verse. Y1 - 2021 U6 - https://doi.org/10.1016/j.media.2021.102166 VL - 73 ER - TY - JOUR A1 - Fügenschuh, Armin A1 - Göttlich, Simone A1 - Herty, Michael A1 - Klar, Alexander A1 - Martin, Alexander T1 - A Discrete Optimization Approach to Large Scale Supply Networks Based on Partial Differential Equations JF - SIAM Journal on Scientific Computing Y1 - 2008 VL - 30 IS - 3 SP - 1490 EP - 1507 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Optimum Path Packing on Wheels: The Consecutive Case N2 - We show that, given a wheel with nonnegative edge lengths and pairs of terminals located on the wheel's outer cycle such that the terminal pairs are in consecutive order, then a path packing, i.~e., a collection of edge disjoint paths connecting the given terminal pairs, of minimum length can be found in strongly polynomial time. Moreover, we exhibit for this case a system of linear inequalities that provides a complete and nonredundant description of the path packing polytope, which is the convex hull of all incidence vectors of path packings and their supersets. T3 - ZIB-Report - SC-95-31 Y1 - 1995 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-1976 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - The Steiner Tree Packing Problem in VLSI-Design. N2 - In this paper we describe several versions of the routing problem arising in VLSI design and indicate how the Steiner tree packing problem can be used to model these problems mathematically. We focus on switchbox routing problems and provide integer programming formulations for routing in the knock-knee and in the Manhattan model. We give a brief sketch of cutting plane algorithms that we developed and implemented for these two models. We report on computational experiments using standard test instances. Our codes are able to determine optimum solutions in most cases, and in particular, we can show that some of the instances have no feasible solution if Manhattan routing is used instead of knock-knee routing. T3 - ZIB-Report - SC-94-02 Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-1328 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Optimum Path Packing on Wheels: The Noncrossing Case. N2 - We show that, given a wheel with nonnegative edge lengths and pairs of terminals located on the wheel's outer cycle such that no two terminal pairs cross, then a path packing, i.~e.,a collection of edge disjoint paths connecting the given terminal pairs, of minimum length can be found in strongly polynomial time. Moreover, we exhibit for this case a system of linear inequalities that provides a complete and nonredundant description of the path packing polytope, which is the convex hull of all incidence vectors of path packings and their supersets. T3 - ZIB-Report - SC-93-26 Y1 - 1993 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-1225 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner Trees: Polyhedral Investigations. N2 - Let $G=(V,E)$ be a graph and $T\subseteq V$ be a node set. We call an edge set $S$ a Steiner tree with respect to $T$ if $S$ connects all pairs of nodes in $T$. In this paper we address the following problem, which we call the weighted Steiner tree packing problem. Given a graph $G=(V,E)$ with edge weights $w_e$, edge capacities $c_e, e \in E,$ and node sets $T_1,\ldots,T_N$, find edge sets $S_1,\ldots,S_N$ such that each $S_k$ is a Steiner tree with respect to $T_k$, at most $c_e$ of these edge sets use edge $e$ for each $e\in E$, and such that the sum of the weights of the edge sets is minimal. Our motivation for studying this problem arises from the routing problem in VLSI-design, where given sets of points have to be connected by wires. We consider the Steiner tree packing Problem from a polyhedral point of view and define an appropriate polyhedron, called the Steiner tree packing polyhedron. The goal of this paper is to (partially) describe this polyhedron by means of inequalities. It turns out that, under mild assumptions, each inequality that defines a facet for the (single) Steiner tree polyhedron can be lifted to a facet-defining inequality for the Steiner tree packing polyhedron. The main emphasis of this paper lies on the presentation of so-called joint inequalities that are valid and facet-defining for this polyhedron. Inequalities of this kind involve at least two Steiner trees. The classes of inequalities we have found form the basis of a branch & cut algorithm. This algorithm is described in our companion paper SC 92-09. T3 - ZIB-Report - SC-92-08 KW - cutting planes KW - Facets KW - Packing KW - polyhedron KW - Steiner tree Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-786 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiners Trees: A Cutting Plane Algorithm and Computational Results. N2 - In this paper we describe a cutting plane algorithm for the Steiner tree packing problem. We use our algorithm to solve some switchbox routing problems of VLSI-design and report on our computational experience. This includes a brief discussion of separation algorithms, a new LP-based primal heuristic and implementation details. The paper is based on the polyhedral theory for the Steiner tree packing polyhedron developed in our companion paper SC 92-8 and meant to turn this theory into an algorithmic tool for the solution of practical problems. T3 - ZIB-Report - SC-92-09 Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-792 ER - TY - GEN A1 - Ferreira, Carlos E. A1 - Grötschel, Martin A1 - Kiefl, Stefan A1 - Krispenz, Ludwig A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Some Integer Programs Arising in the Design of Main Frame Computers. N2 - In this paper we describe and discuss a problem that arises in the (global) design of a main frame computer. The task is to assign certain functional units to a given number of so called multi chip modules or printed circuit boards taking into account many technical constraints and minimizing a complex objective function. We describe the real world problem. A thorough mathematical modelling of all aspects of this problem results in a rather complicated integer program that seems to be hopelessly difficult -- at least for the present state of integer programming technology. We introduce several relaxations of the general model, which are also $NP$-hard, but seem to be more easily accessible. The mathematical relations between the relaxations and the exact formulation of the problem are discussed as well. T3 - ZIB-Report - SC-92-25 Y1 - 1993 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-957 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Routing in Grid Graphs by Cutting Planes. N2 - {\def\N{{\cal N}} \def\R{\hbox{\rm I\kern-2pt R}} \def\MN{{\rm I\kern-2pt N}} In this paper we study the following problem, which we call the weighted routing problem. Let be given a graph $G=(V,E)$ with non-negative edge weights $w_e\in\R_+$ and integer edge capacities $c_e\in\MN$ and let $\N=\{T_1,\ldots,T_N\}$, $N\ge 1$, be a list of node sets. The weighted routing problem consists in finding edge sets $S_1,\ldots,S_N$ such that, for each $k\in\{1,\ldots,N\}$, the subgraph $(V(S_k),S_k)$ contains an $[s,t]$-path for all $s,t\in T_k$, at most $c_e$ of these edge sets use edge $e$ for each $e\in E$, and such that the sum of the weights of the edge sets is minimal. Our motivation for studying this problem arises from the routing problem in VLSI-design, where given sets of points have to be connected by wires. We consider the weighted routing problem from a polyhedral point of view. We define an appropriate polyhedron and try to (partially) describe this polyhedron by means of inequalities. We briefly sketch our separation algorithms for some of the presented classes of inequalities. Based on these separation routines we have implemented a branch and cut algorithm. Our algorithm is applicable to an important subclass of routing problems arising in VLSI-design, namely to problems where the underlying graph is a grid graph and the list of node sets is located on the outer face of the grid. We report on our computational experience with this class of problem instances.} T3 - ZIB-Report - SC-92-26 KW - routing in VLSI-design KW - Steiner tree KW - Steiner tree packing KW - cutting plane algorithm Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-967 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner Trees: Further Facets. N2 - In this paper we continue the investigations in [GMW92a] for the \def\sbppo{Steiner tree packing polyhedron} \sbppo. We present several new classes of valid inequalities and give sufficient (and necessary) conditions for these inequalities to be facet-defining. It is intended to incorporate these inequalities into an existing cutting plane algorithm that is applicable to practical problems arising in the design of electronic circuits. T3 - ZIB-Report - SC-93-01 Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-975 ER - TY - GEN A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner Trees: Separation Algorithms. N2 - In this paper we investigate separation problems for classes of inequalities valid for the polytope associated with the Steiner tree packing problem, a problem that arises, e.~g., in VLSI routing. The separation problem for Steiner partition inequalities is ${\cal N}\hskip-2pt{\cal P}$-hard in general. We show that it can be solved in polynomial time for those instances that come up in switchbox routing. Our algorithm uses dynamic programming techniques. These techniques are also applied to the much more complicated separation problem for alternating cycle inequalities. In this case we can compute in polynomial time, given some point $y$, a lower bound for the gap $\alpha-a^Ty$ over all alternating cycle inequalities $a^Tx\ge\alpha$. This gives rise to a very effective separation heuristic. A by-product of our algorithm is the solution of a combinatorial optimization problem that is interesting in its own right: Find a shortest path in a graph where the ``length'' of a path is its usual length minus the length of its longest edge. T3 - ZIB-Report - SC-93-02 Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-984 ER - TY - GEN A1 - Borndörfer, Ralf A1 - Eisenblätter, Andreas A1 - Grötschel, Martin A1 - Martin, Alexander T1 - Frequency Assignment in Cellular Phone Networks N2 - We present a graph-theoretic model for the \emph{frequency assignment problem} in Cellular Phone Networks: Obeying several technical and legal restrictions, frequencies have to be assigned to transceivers so that interference is as small as possible. This optimization problem is NP-hard. Good approximation cannot be guaranteed, unless P = NP. We describe several assignment heuristics. These heuristics are simple and not too hard to implement. We give an assessment of the heuristics' efficiency and practical usefulness. For this purpose, typical instances of frequency assignment problems with up to 4240 transceivers and 75 frequencies of a German cellular phone network operator are used. The results are satisfying from a practitioner's point of view. The best performing heuristics were integrated into a network planning system used in practice. T3 - ZIB-Report - SC-97-35 Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-3044 ER - TY - GEN A1 - Bruns, Winfried A1 - Gubeladze, Joseph A1 - Henk, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - A counterexample to an integer analogue of Caratheodorys theorem N2 - For $n\geq 6$ we provide a counterexample to the conjecture that every integral vector of a $n$-dimensional integral polyhedral pointed cone $C$ can be written as a nonnegative integral combination of at most $n$ elements of the Hilbert basis of $C$. In fact, we show that in general at least $\lfloor 7/6 \cdot n \rfloor$ elements of the Hilbert basis are needed. T3 - ZIB-Report - SC-98-28 KW - Integral pointed cones KW - Hilbert basis KW - integral Carathéodory property Y1 - 1998 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-3718 ER - TY - JOUR A1 - Aigner, Kevin-Martin A1 - Clarner, Jan-Patrick A1 - Liers, Frauke A1 - Martin, Alexander T1 - Robust Approximation of Chance Constrained DC Optimal Power Flow under Decision-Dependent Uncertainty JF - European Journal of Operational Research N2 - We propose a mathematical optimization model and its solution for joint chance constrained DC Optimal Power Flow. In this application, it is particularly important that there is a high probability of transmission limits being satisfied, even in the case of uncertain or fluctuating feed-in from renewable energy sources. In critical network situations where the network risks overload, renewable energy feed-in has to be curtailed by the transmission system operator (TSO). The TSO can reduce the feed-in in discrete steps at each network node. The proposed optimization model minimizes curtailment while ensuring that there is a high probability of transmission limits being maintained. The latter is modeled via (joint) chance constraints that are computationally challenging. Thus, we propose a solution approach based on the robust safe approximation of these constraints. Hereby, probabilistic constraints are replaced by robust constraints with suitably defined uncertainty sets constructed from historical data. The ability to discretely control the power feed-in then leads to a robust optimization problem with decision-dependent uncertainties, i.e. the uncertainty sets depend on decision variables. We propose an equivalent mixed-integer linear reformulation for box uncertainties with the exact linearization of bilinear terms. Finally, we present numerical results for different test cases from the Nesta archive, as well as for a real network. We consider the discrete curtailment of solar feed-in, for which we use real-world weather and network data. The experimental tests demonstrate the effectiveness of this method and run times are very fast. Moreover, on average the calculated robust solutions only lead to a small increase in curtailment, when compared to nominal solutions. Y1 - 2021 ER - TY - JOUR A1 - Koch, Thorsten A1 - Schmidt, Martin A1 - Hiller, Benjamin A1 - Pfetsch, Marc A1 - Geißler, Björn A1 - Henrion, René A1 - Joormann, Imke A1 - Martin, Alexander A1 - Morsi, Antonio A1 - Römisch, Werner A1 - Schewe, Lars A1 - Schultz, Rüdiger T1 - Capacity Evaluation for Large-Scale Gas Networks JF - German Success Stories in Industrial Mathematics Y1 - 2020 SN - 978-3-030-81454-0 U6 - https://doi.org/10.1007/978-3-030-81455-7 VL - 35 SP - 23 EP - 28 ER - TY - GEN A1 - Borndörfer, Ralf A1 - Eisenblätter, Andreas A1 - Grötschel, Martin A1 - Martin, Alexander T1 - The Orientation Model for Frequency Assignment Problems N2 - Mobile telecommunication systems establish a large number of communication links with a limited number of available frequencies; reuse of the same or adjacent frequencies on neighboring links causes interference. The task to find an assignment of frequencies to channels with minimal interference is the frequency assignment problem. The frequency assignment problem is usually treated as a graph coloring problem where the number of colors is minimized, but this approach does not model interference minimization correctly. We give in this paper a new integer programming formulation of the frequency assignment problem, the orientation model, and develop a heuristic two-stage method to solve it. The algorithm iteratively solves an outer and an inner optimization problem. The outer problem decides for each pair of communication links which link gets the higher frequency and leads to an acyclic subdigraph problem with additional longest path restrictions. The inner problem to find an optimal assignment respecting an orientation leads to a min-cost flow problem. T3 - ZIB-Report - TR-98-01 KW - Minimum-Cost Flow Problems KW - Cellular Radio Telephone Systems KW - Frequency Assignment Problem KW - Integer Programming Y1 - 1998 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-5627 ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner trees: Polyhedral Investigations JF - Mathematical Programming, Series A Y1 - 1996 U6 - https://doi.org/10.1007/BF02592085 VL - 72 IS - 2 SP - 101 EP - 123 ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Optimum Path Packing on Wheels JF - Computers and Mathematics with Applications Y1 - 1996 VL - 31 IS - 11 SP - 23 EP - 35 PB - Elsevier ER - TY - JOUR A1 - Borndörfer, Ralf A1 - Eisenblätter, Andreas A1 - Grötschel, Martin A1 - Martin, Alexander T1 - Frequency assignment in cellular phone networks JF - Annals of Operations Research Y1 - 1998 U6 - https://doi.org/10.1023/A:1018908907763 VL - 76 SP - 73 EP - 93 PB - J. C. Baltzer AG, Science Publishers ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner trees: a cutting plane algorithm and computational results JF - Mathematical Programming, Series A Y1 - 1996 U6 - https://doi.org/10.1007/BF02592086 VL - 72 IS - 2 SP - 125 EP - 145 ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - The Steiner tree packing problem in VLSI design JF - Mathematical Programming Y1 - 1997 VL - 78 IS - 2 SP - 265 EP - 281 ER - TY - CHAP A1 - Birkhofer, Herbert A1 - Fügenschuh, Armin A1 - Günther, Ute A1 - Junglas, Daniel A1 - Martin, Alexander A1 - Sauer, Thorsten A1 - Ulbrich, Stefan A1 - Wäldele, Martin A1 - Walter, Stephan ED - Haasis, Hans-Dietrich ED - Kopfer, Herbert ED - Schönberger, Jörn T1 - Topology- and shape-optimization of branched sheet metal products T2 - Operations Research Proceedings Y1 - 2006 SP - 327 EP - 336 ER - TY - CHAP A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert ED - Rinaldi, Giovanni ED - Wolsey, Laurence T1 - Routing in grid graphs by cutting planes T2 - Integer Programming and Combinatorial Optimization. Proceedings of a Conference held at Centro Ettore Majorana, Erice, Italy, April 29 - May 1, 1993 Y1 - 1993 SP - 447 EP - 461 PB - Librarian CORE CY - Louvain-la-Neuve ER - TY - CHAP A1 - Birkhofer, Herbert A1 - Fügenschuh, Armin A1 - Martin, Alexander A1 - Wäldele, Martin T1 - Algorithmenbasierte Produktentwicklung für integrale Blechbauweisen höherer Verzweigungsordnung T2 - Optimierung in der Produktentwicklung, 5. Geimeinsames Kolloquium Konstruktionstechnik Y1 - 2007 ER - TY - JOUR A1 - Pfetsch, Marc A1 - Fügenschuh, Armin A1 - Geißler, Björn A1 - Geißler, Nina A1 - Gollmer, Ralf A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Martin, Alexander A1 - Morsi, Antonio A1 - Rövekamp, Jessica A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Stangl, Claudia A1 - Steinbach, Marc A1 - Vigerske, Stefan A1 - Willert, Bernhard T1 - Validation of Nominations in Gas Network Optimization: Models, Methods, and Solutions JF - Optimization Methods and Software N2 - In this article we investigate methods to solve a fundamental task in gas transportation, namely the validation of nomination problem: Given a gas transmission network consisting of passive pipelines and active, controllable elements and given an amount of gas at every entry and exit point of the network, find operational settings for all active elements such that there exists a network state meeting all physical, technical, and legal constraints. We describe a two-stage approach to solve the resulting complex and numerically difficult feasibility problem. The first phase consists of four distinct algorithms applying linear, and methods for complementarity constraints to compute possible settings for the discrete decisions. The second phase employs a precise continuous programming model of the gas network. Using this setup, we are able to compute high quality solutions to real-world industrial instances that are significantly larger than networks that have appeared in the mathematical programming literature before. Y1 - 2014 U6 - https://doi.org/10.1080/10556788.2014.888426 PB - Taylor & Francis ER - TY - JOUR A1 - Fügenschuh, Armin A1 - Geißler, Björn A1 - Gollmer, Ralf A1 - Hayn, Christine A1 - Henrion, René A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Martin, Alexander A1 - Mirkov, Radoslava A1 - Morsi, Antonio A1 - Römisch, Werner A1 - Rövekamp, Jessica A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Stangl, Claudia A1 - Steinbach, Marc A1 - Willert, Bernhard T1 - Mathematical optimization for challenging network planning problems in unbundled liberalized gas markets JF - Energy Systems N2 - The recently imposed new gas market liberalization rules in Germany lead to a change of business of gas network operators. While previously network operator and gas vendor were united, they were forced to split up into independent companies. The network has to be open to any other gas trader at the same conditions, and free network capacities have to be identified and publicly offered in a non-discriminatory way. We discuss how these changing paradigms lead to new and challenging mathematical optimization problems. This includes the validation of nominations, that asks for the decision if the network’s capacity is sufficient to transport a specific amount of flow, the verification of booked capacities and the detection of available freely allocable capacities, and the topological extension of the network with new pipelines or compressors in order to increase its capacity. In order to solve each of these problems and to provide meaningful results for the practice, a mixture of different mathematical aspects have to be addressed, such as combinatorics, stochasticity, uncertainty, and nonlinearity. Currently, no numerical solver is available that can deal with such blended problems out-of-the-box. The main goal of our research is to develop such a solver, that moreover is able to solve instances of realistic size. In this article, we describe the main ingredients of our prototypical software implementations. Y1 - 2013 U6 - https://doi.org/10.1007/s12667-013-0099-8 VL - 5 IS - 3 SP - 449 EP - 473 PB - Springer Berlin Heidelberg CY - Berlin ER - TY - JOUR A1 - Ferreira, Carlos A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert A1 - Kiefl, Stefan A1 - Krispenz, Ludwig T1 - Some Integer Programs Arising in the Design of Main Frame Computers JF - ZOR - Methods and Models of Operations Research Y1 - 1993 VL - 38 IS - 1 SP - 77 EP - 100 ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Routing in Grid Graphs by Cutting Planes JF - ZOR - Mathematical Methods of Operations Research Y1 - 1995 VL - 41 IS - 3 SP - 255 EP - 275 ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner Trees: Separation Algorithms JF - SIAM Journal on Discrete Mathematics Y1 - 1996 U6 - https://doi.org/10.1137/S0895480193258716 VL - 9 IS - 2 SP - 233 EP - 257 ER - TY - CHAP A1 - Martin, Alexander A1 - Geißler, Björn A1 - Heyn, Christine A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Morsi, Antonio A1 - Pfetsch, Marc A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Steinbach, Marc A1 - Willert, Bernhard T1 - Optimierung Technischer Kapazitäten in Gasnetzen T2 - Optimierung in der Energiewirtschaft Y1 - 2011 SP - 105 EP - 114 PB - VDI-Verlag, Düsseldorf ER - TY - JOUR A1 - Grötschel, Martin A1 - Martin, Alexander A1 - Weismantel, Robert T1 - Packing Steiner Trees: Further Facets JF - European Journal of Combinatorics Y1 - 1996 U6 - https://doi.org/10.1006/eujc.1996.0004 VL - 17 IS - 1 SP - 39 EP - 52 ER - TY - GEN A1 - Martin, Alexander A1 - Geißler, Björn A1 - Hayn, Christine A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Morsi, Antonio A1 - Pfetsch, Marc A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Steinbach, Marc A1 - Willert, Bernhard T1 - Optimierung Technischer Kapazitäten in Gasnetzen N2 - Die mittel- und längerfristige Planung für den Gastransport hat sich durch Änderungen in den regulatorischen Rahmenbedingungen stark verkompliziert. Kernpunkt ist die Trennung von Gashandel und -transport. Dieser Artikel diskutiert die hieraus resultierenden mathematischen Planungsprobleme, welche als Validierung von Nominierungen und Buchungen, Bestimmung der technischen Kapazität und Topologieplanung bezeichnet werden. Diese mathematischen Optimierungsprobleme werden vorgestellt und Lösungsansätze skizziert. T3 - ZIB-Report - 11-56 KW - Gasnetzplanung KW - Technische Kapazitäten KW - Nominierungsvalidierung KW - Buchungsvalidierung KW - Topologieplanung Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-15121 SN - 1438-0064 ER - TY - CHAP A1 - Borndörfer, Ralf A1 - Eisenblätter, Andreas A1 - Grötschel, Martin A1 - Martin, Alexander T1 - Stable-Set and Other Techniques for Frequency Assignment Problems T2 - Anais da I Oficina Nacional em Problemas de Corte & Empacotamento Y1 - 1996 SP - 17 EP - 21 PB - Universidade de São Paulo, Instituto de Matemática e Estatística ER - TY - GEN A1 - Fügenschuh, Armin A1 - Geißler, Björn A1 - Gollmer, Ralf A1 - Hayn, Christine A1 - Henrion, Rene A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Martin, Alexander A1 - Mirkov, Radoslava A1 - Morsi, Antonio A1 - Römisch, Werner A1 - Rövekamp, Jessica A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Stangl, Claudia A1 - Steinbach, Marc A1 - Willert, Bernhard T1 - Mathematical Optimization for Challenging Network Planning Problems in Unbundled Liberalized Gas Markets N2 - The recently imposed new gas market liberalization rules in Germany lead to a change of business of gas network operators. While previously network operator and gas vendor where united, they were forced to split up into independent companies. The network has to be open to any other gas trader at the same conditions, and free network capacities have to be identified and publicly offered in a non-discriminatory way. We show that these new paradigms lead to new and challenging mathematical optimization problems. In order to solve them and to provide meaningful results for practice, all aspects of the underlying problems, such as combinatorics, stochasticity, uncertainty, and nonlinearity, have to be addressed. With such special-tailored solvers, free network capacities and topological network extensions can, for instance, be determined. T3 - ZIB-Report - 13-13 KW - Gas Market Liberalization KW - Entry-Exit Model KW - Gas Network Access Regulation KW - Mixed-Integer Nonlinear Nonconvex Stochastic Optimization Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-17821 SN - 1438-0064 ER - TY - GEN A1 - Pfetsch, Marc A1 - Fügenschuh, Armin A1 - Geißler, Björn A1 - Geißler, Nina A1 - Gollmer, Ralf A1 - Hiller, Benjamin A1 - Humpola, Jesco A1 - Koch, Thorsten A1 - Lehmann, Thomas A1 - Martin, Alexander A1 - Morsi, Antonio A1 - Rövekamp, Jessica A1 - Schewe, Lars A1 - Schmidt, Martin A1 - Schultz, Rüdiger A1 - Schwarz, Robert A1 - Schweiger, Jonas A1 - Stangl, Claudia A1 - Steinbach, Marc A1 - Vigerske, Stefan A1 - Willert, Bernhard T1 - Validation of Nominations in Gas Network Optimization: Models, Methods, and Solutions N2 - In this article we investigate methods to solve a fundamental task in gas transportation, namely the validation of nomination problem: Given a gas transmission network consisting of passive pipelines and active, controllable elements and given an amount of gas at every entry and exit point of the network, find operational settings for all active elements such that there exists a network state meeting all physical, technical, and legal constraints. We describe a two-stage approach to solve the resulting complex and numerically difficult mixed-integer non-convex nonlinear feasibility problem. The first phase consists of four distinct algorithms facilitating mixed-integer linear, mixed-integer nonlinear, reduced nonlinear, and complementarity constrained methods to compute possible settings for the discrete decisions. The second phase employs a precise continuous nonlinear programming model of the gas network. Using this setup, we are able to compute high quality solutions to real-world industrial instances whose size is significantly larger than networks that have appeared in the literature previously. T3 - ZIB-Report - 12-41 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-16531 SN - 1438-0064 ER - TY - GEN A1 - Achterberg, Tobias A1 - Koch, Thorsten A1 - Martin, Alexander T1 - MIPLIB 2003 N2 - This paper reports on the fourth version of the Mixed Integer Programming Library. Since ({\sc miplib}) is to provide a concise set of challenging problems, it became necessary to purge instances that became too easy. We present an overview of the 27 new problems and statistical data for all 60 instances. T3 - ZIB-Report - 05-28 KW - Mathematical Programming KW - Mixed Integer Programming KW - IP KW - MIP KW - Optimization KW - Instances Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-8625 ER - TY - JOUR A1 - Martin, Alexander A1 - Müller, J. A1 - Pokutta, Sebastian T1 - Strict linear prices in non-convex European day-ahead electricity markets JF - Optimization Methods and Software Y1 - 2014 UR - http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1660528 N1 - Additional Note: 10.1080/10556788.2013.823544 N1 - URL of the PDF: http://dx.doi.org/10.1080/10556788.2013.823544 VL - 29 IS - 1 SP - 189 EP - 221 ER - TY - BOOK A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander T1 - Geometric Algorithms and Combinatorial Optimization T3 - Algorithms and Combinatorics Y1 - 1988 SN - 3-540-13624-X, 0-387-13624-X (U.S.) VL - 2 PB - Springer ER - TY - CHAP A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander ED - Pulleyblank, William T1 - Geometric Methods in Combinatorial Optimization T2 - Progress in Combinatorial Optimization, (Conference Waterloo/Ontario 1982) Y1 - 1984 SP - 167 EP - 183 PB - Academic Press ER - TY - CHAP A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander ED - Berge, Claude ED - Chvátal, Vašek T1 - Polynomial algorithms for perfect graphs T2 - Topics on perfect graphs Y1 - 1984 VL - 21 SP - 325 EP - 356 PB - North-Holland ER - TY - JOUR A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander T1 - Corrigendum to our paper “The ellipsoid method and its consequences in combinatorial optimization” JF - Combinatorica Y1 - 1984 VL - 4 IS - 4 SP - 291 EP - 295 ER - TY - JOUR A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander T1 - Relaxations of Vertex Packing JF - Journal of Combinatorial Theory, Series B Y1 - 1986 VL - 40 SP - 330 EP - 343 ER - TY - JOUR A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander T1 - The ellipsoid method and its consequences in combinatorial optimization JF - Combinatorica Y1 - 1981 VL - 1 IS - 2 SP - 169 EP - 197 ER - TY - JOUR A1 - Grötschel, Martin A1 - Lovász, Lászlo A1 - Schrijver, Alexander T1 - The ellipsoid method and its consequences in combinatorial optimization JF - IIASA Collab. Proceedings Ser. CP-81-S1 Y1 - 1981 SP - 511 EP - 546 ER - TY - JOUR A1 - Achterberg, Tobias A1 - Koch, Thorsten A1 - Martin, Alexander T1 - MIPLIB 2003 JF - Operations Research Letters Y1 - 2006 UR - http://opus.kobv.de/zib/volltexte/2005/862/ U6 - https://doi.org/10.1016/j.orl.2005.07.009 VL - 34 IS - 4 SP - 361 EP - 372 PB - Elsevier / North-Holland ER -