@inproceedings{WeinholdLackorzynskiBierbaumetal.2019, author = {Weinhold, Carsten and Lackorzynski, Adam and Bierbaum, Jan and K{\"u}ttler, Martin and Planeta, Maksym and Weisbach, Hannes and Hille, Matthias and H{\"a}rtig, Hermann and Margolin, Alexander and Sharf, Dror and Levy, Ely and Gak, Pavel and Barak, Amnon and Gholami, Masoud and Schintke, Florian and Sch{\"u}tt, Thorsten and Reinefeld, Alexander and Lieber, Matthias and Nagel, Wolfgang}, title = {FFMK: A Fast and Fault-Tolerant Microkernel-Based System for Exascale Computing}, booktitle = {Software for Exascale Computing - SPPEXA 2016-2019}, publisher = {Springer}, doi = {10.1007/978-3-030-47956-5_16}, pages = {483 -- 516}, year = {2019}, language = {en} } @article{EnkeSteinmetzAdorfetal.2011, author = {Enke, Harry and Steinmetz, Matthias and Adorf, Hans-Martin and Beck-Ratzka, Alexander and Breitling, Frank and Br{\"u}semeister, Thomas and Carlson, Arthur and Ensslin, Torsten and H{\"o}gqvist, Mikael and Nickelt, Iliya and Radke, Thomas and Reinefeld, Alexander and Reiser, Angelika and Scholl, Tobias and Spurzem, Rainer and Steinacker, J{\"u}rgen and Voges, Wolfgang and Wambsganß, Joachim and White, Steve}, title = {AstroGrid-D: Grid technology for astronomical science}, volume = {16}, journal = {New Astronomy}, number = {2}, doi = {10.1016/j.newast.2010.07.005}, pages = {79 -- 93}, year = {2011}, language = {en} } @article{SekuboyinaBayatHusseinietal.2020, author = {Sekuboyina, Anjany and Bayat, Amirhossein and Husseini, Malek E. and L{\"o}ffler, Maximilian and Li, Hongwei and Tetteh, Giles and Kukačka, Jan and Payer, Christian and Štern, Darko and Urschler, Martin and Chen, Maodong and Cheng, Dalong and Lessmann, Nikolas and Hu, Yujin and Wang, Tianfu and Yang, Dong and Xu, Daguang and Ambellan, Felix and Amiranashvili, Tamaz and Ehlke, Moritz and Lamecker, Hans and Lehnert, Sebastian and Lirio, Marilia and de Olaguer, Nicol{\´a}s P{\´e}rez and Ramm, Heiko and Sahu, Manish and Tack, Alexander and Zachow, Stefan and Jiang, Tao and Ma, Xinjun and Angerman, Christoph and Wang, Xin and Wei, Qingyue and Brown, Kevin and Wolf, Matthias and Kirszenberg, Alexandre and Puybareau, {\´E}lodie and Valentinitsch, Alexander and Rempfler, Markus and Menze, Bj{\"o}rn H. and Kirschke, Jan S.}, title = {VerSe: A Vertebrae Labelling and Segmentation Benchmark for Multi-detector CT Images}, journal = {arXiv}, arxiv = {http://arxiv.org/abs/2001.09193}, year = {2020}, language = {en} } @article{SchimunekSeidlElezetal.2024, author = {Schimunek, Johannes and Seidl, Philipp and Elez, Katarina and Hempel, Tim and Le, Tuan and No{\´e}, Frank and Olsson, Simon and Raich, Llu{\´i}s and Winter, Robin and Gokcan, Hatice and Gusev, Filipp and Gutkin, Evgeny M. and Isayev, Olexandr and Kurnikova, Maria G. and Narangoda, Chamali H. and Zubatyuk, Roman and Bosko, Ivan P. and Furs, Konstantin V. and Karpenko, Anna D. and Kornoushenko, Yury V. and Shuldau, Mikita and Yushkevich, Artsemi and Benabderrahmane, Mohammed B. and Bousquet-Melou, Patrick and Bureau, Ronan and Charton, Beatrice and Cirou, Bertrand C. and Gil, G{\´e}rard and Allen, William J. and Sirimulla, Suman and Watowich, Stanley and Antonopoulos, Nick and Epitropakis, Nikolaos and Krasoulis, Agamemnon and Itsikalis, Vassilis and Theodorakis, Stavros and Kozlovskii, Igor and Maliutin, Anton and Medvedev, Alexander and Popov, Petr and Zaretckii, Mark and Eghbal-Zadeh, Hamid and Halmich, Christina and Hochreiter, Sepp and Mayr, Andreas and Ruch, Peter and Widrich, Michael and Berenger, Francois and Kumar, Ashutosh and Yamanishi, Yoshihiro and Zhang, Kam Y. J. and Bengio, Emmanuel and Bengio, Yoshua and Jain, Moksh J. and Korablyov, Maksym and Liu, Cheng-Hao and Marcou, Gilles and Glaab, Enrico and Barnsley, Kelly and Iyengar, Suhasini M. and Ondrechen, Mary Jo and Haupt, V. Joachim and Kaiser, Florian and Schroeder, Michael and Pugliese, Luisa and Albani, Simone and Athanasiou, Christina and Beccari, Andrea and Carloni, Paolo and D'Arrigo, Giulia and Gianquinto, Eleonora and Goßen, Jonas and Hanke, Anton and Joseph, Benjamin P. and Kokh, Daria B. and Kovachka, Sandra and Manelfi, Candida and Mukherjee, Goutam and Mu{\~n}iz-Chicharro, Abraham and Musiani, Francesco and Nunes-Alves, Ariane and Paiardi, Giulia and Rossetti, Giulia and Sadiq, S. Kashif and Spyrakis, Francesca and Talarico, Carmine and Tsengenes, Alexandros and Wade, Rebecca C. and Copeland, Conner and Gaiser, Jeremiah and Olson, Daniel R. and Roy, Amitava and Venkatraman, Vishwesh and Wheeler, Travis J. and Arthanari, Haribabu and Blaschitz, Klara and Cespugli, Marco and Durmaz, Vedat and Fackeldey, Konstantin and Fischer, Patrick D. and Gorgulla, Christoph and Gruber, Christian and Gruber, Karl and Hetmann, Michael and Kinney, Jamie E. and Padmanabha Das, Krishna M. and Pandita, Shreya and Singh, Amit and Steinkellner, Georg and Tesseyre, Guilhem and Wagner, Gerhard and Wang, Zi-Fu and Yust, Ryan J. and Druzhilovskiy, Dmitry S. and Filimonov, Dmitry A. and Pogodin, Pavel V. and Poroikov, Vladimir and Rudik, Anastassia V. and Stolbov, Leonid A. and Veselovsky, Alexander V. and De Rosa, Maria and De Simone, Giada and Gulotta, Maria R. and Lombino, Jessica and Mekni, Nedra and Perricone, Ugo and Casini, Arturo and Embree, Amanda and Gordon, D. Benjamin and Lei, David and Pratt, Katelin and Voigt, Christopher A. and Chen, Kuang-Yu and Jacob, Yves and Krischuns, Tim and Lafaye, Pierre and Zettor, Agn{\`e}s and Rodr{\´i}guez, M. Luis and White, Kris M. and Fearon, Daren and Von Delft, Frank and Walsh, Martin A. and Horvath, Dragos and Brooks III, Charles L. and Falsafi, Babak and Ford, Bryan and Garc{\´i}a-Sastre, Adolfo and Yup Lee, Sang and Naffakh, Nadia and Varnek, Alexandre and Klambauer, G{\"u}nter and Hermans, Thomas M.}, title = {A community effort in SARS-CoV-2 drug discovery}, volume = {43}, journal = {Molecular Informatics}, number = {1}, doi = {https://doi.org/10.1002/minf.202300262}, pages = {e202300262}, year = {2024}, language = {en} } @article{LuetzkendorfMatkovicRachidLiuetal.2025, author = {L{\"u}tzkendorf, Janine and Matkovic-Rachid, Tanja and Liu, Sunbin and G{\"o}tz, Torsten and Gao, Lili and Turrel, Oriane and Maglione, Marta and Grieger, Melanie and Putignano, Sabrina and Ramesh, Niraja and Ghelani, Tina and Neumann, Alexander and Gimber, Niclas and Schmoranzer, Jan and Stawrakakis, Anastasia and Brence, Blaž and Baum, Daniel and Ludwig, Kai and Heine, Martin and Mielke, Thorsten and Liu, Fan and Walter, Alexander and Wahl, Markus and Sigrist, Stephan}, title = {Blobby is a synaptic active zone assembly protein required for memory in Drosophila}, volume = {16}, journal = {Nature Communications}, doi = {10.1038/s41467-024-55382-9}, year = {2025}, language = {en} } @article{SekuboyinaHusseiniBayatetal.2021, author = {Sekuboyina, Anjany and Husseini, Malek E. and Bayat, Amirhossein and L{\"o}ffler, Maximilian and Liebl, Hans and Li, Hongwei and Tetteh, Giles and Kukačka, Jan and Payer, Christian and Štern, Darko and Urschler, Martin and Chen, Maodong and Cheng, Dalong and Lessmann, Nikolas and Hu, Yujin and Wang, Tianfu and Yang, Dong and Xu, Daguang and Ambellan, Felix and Amiranashvili, Tamaz and Ehlke, Moritz and Lamecker, Hans and Lehnert, Sebastian and Lirio, Marilia and de Olaguer, Nicol{\´a}s P{\´e}rez and Ramm, Heiko and Sahu, Manish and Tack, Alexander and Zachow, Stefan and Jiang, Tao and Ma, Xinjun and Angerman, Christoph and Wang, Xin and Brown, Kevin and Kirszenberg, Alexandre and Puybareau, {\´E}lodie and Chen, Di and Bai, Yiwei and Rapazzo, Brandon H. and Yeah, Timyoas and Zhang, Amber and Xu, Shangliang and Hou, Feng and He, Zhiqiang and Zeng, Chan and Xiangshang, Zheng and Liming, Xu and Netherton, Tucker J. and Mumme, Raymond P. and Court, Laurence E. and Huang, Zixun and He, Chenhang and Wang, Li-Wen and Ling, Sai Ho and Huynh, L{\^e} Duy and Boutry, Nicolas and Jakubicek, Roman and Chmelik, Jiri and Mulay, Supriti and Sivaprakasam, Mohanasankar and Paetzold, Johannes C. and Shit, Suprosanna and Ezhov, Ivan and Wiestler, Benedikt and Glocker, Ben and Valentinitsch, Alexander and Rempfler, Markus and Menze, Bj{\"o}rn H. and Kirschke, Jan S.}, title = {VerSe: A Vertebrae labelling and segmentation benchmark for multi-detector CT images}, volume = {73}, journal = {Medical Image Analysis}, doi = {10.1016/j.media.2021.102166}, year = {2021}, abstract = {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.}, language = {en} } @article{FuegenschuhGoettlichHertyetal.2008, author = {F{\"u}genschuh, Armin and G{\"o}ttlich, Simone and Herty, Michael and Klar, Alexander and Martin, Alexander}, title = {A Discrete Optimization Approach to Large Scale Supply Networks Based on Partial Differential Equations}, volume = {30}, journal = {SIAM Journal on Scientific Computing}, number = {3}, pages = {1490 -- 1507}, year = {2008}, language = {en} } @misc{GroetschelMartinWeismantel1995, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Optimum Path Packing on Wheels: The Consecutive Case}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1976}, number = {SC-95-31}, year = {1995}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1994, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {The Steiner Tree Packing Problem in VLSI-Design.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1328}, number = {SC-94-02}, year = {1994}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1993, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Optimum Path Packing on Wheels: The Noncrossing Case.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1225}, number = {SC-93-26}, year = {1993}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1992, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner Trees: Polyhedral Investigations.}, doi = {10.1007/BF02592085}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-786}, number = {SC-92-08}, year = {1992}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1992, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiners Trees: A Cutting Plane Algorithm and Computational Results.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-792}, number = {SC-92-09}, year = {1992}, abstract = {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.}, language = {en} } @misc{FerreiraGroetschelKiefletal.1993, author = {Ferreira, Carlos E. and Gr{\"o}tschel, Martin and Kiefl, Stefan and Krispenz, Ludwig and Martin, Alexander and Weismantel, Robert}, title = {Some Integer Programs Arising in the Design of Main Frame Computers.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-957}, number = {SC-92-25}, year = {1993}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1992, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Routing in Grid Graphs by Cutting Planes.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-967}, number = {SC-92-26}, year = {1992}, abstract = {{\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.}}, language = {en} } @misc{GroetschelMartinWeismantel1992, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner Trees: Further Facets.}, doi = {10.1006/eujc.1996.0004}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-975}, number = {SC-93-01}, year = {1992}, abstract = {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.}, language = {en} } @misc{GroetschelMartinWeismantel1992, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner Trees: Separation Algorithms.}, doi = {10.1137/S0895480193258716}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-984}, number = {SC-93-02}, year = {1992}, abstract = {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.}, language = {en} } @misc{BorndoerferEisenblaetterGroetscheletal.1997, author = {Bornd{\"o}rfer, Ralf and Eisenbl{\"a}tter, Andreas and Gr{\"o}tschel, Martin and Martin, Alexander}, title = {Frequency Assignment in Cellular Phone Networks}, doi = {10.1023/A:1018908907763}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3044}, number = {SC-97-35}, year = {1997}, abstract = {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.}, language = {en} } @misc{BrunsGubeladzeHenketal.1998, author = {Bruns, Winfried and Gubeladze, Joseph and Henk, Martin and Martin, Alexander and Weismantel, Robert}, title = {A counterexample to an integer analogue of Caratheodorys theorem}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3718}, number = {SC-98-28}, year = {1998}, abstract = {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.}, language = {en} } @article{AignerClarnerLiersetal.2021, author = {Aigner, Kevin-Martin and Clarner, Jan-Patrick and Liers, Frauke and Martin, Alexander}, title = {Robust Approximation of Chance Constrained DC Optimal Power Flow under Decision-Dependent Uncertainty}, journal = {European Journal of Operational Research}, year = {2021}, abstract = {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.}, language = {en} } @article{KochSchmidtHilleretal.2020, author = {Koch, Thorsten and Schmidt, Martin and Hiller, Benjamin and Pfetsch, Marc and Geißler, Bj{\"o}rn and Henrion, Ren{\´e} and Joormann, Imke and Martin, Alexander and Morsi, Antonio and R{\"o}misch, Werner and Schewe, Lars and Schultz, R{\"u}diger}, title = {Capacity Evaluation for Large-Scale Gas Networks}, volume = {35}, journal = {German Success Stories in Industrial Mathematics}, isbn = {978-3-030-81454-0}, doi = {10.1007/978-3-030-81455-7}, pages = {23 -- 28}, year = {2020}, language = {en} } @misc{BorndoerferEisenblaetterGroetscheletal.1998, author = {Bornd{\"o}rfer, Ralf and Eisenbl{\"a}tter, Andreas and Gr{\"o}tschel, Martin and Martin, Alexander}, title = {The Orientation Model for Frequency Assignment Problems}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-5627}, number = {TR-98-01}, year = {1998}, abstract = {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.}, language = {en} } @article{GroetschelMartinWeismantel1996, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner trees: Polyhedral Investigations}, volume = {72}, journal = {Mathematical Programming, Series A}, number = {2}, doi = {10.1007/BF02592085}, pages = {101 -- 123}, year = {1996}, language = {en} } @article{GroetschelMartinWeismantel1996, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Optimum Path Packing on Wheels}, volume = {31}, journal = {Computers and Mathematics with Applications}, number = {11}, publisher = {Elsevier}, pages = {23 -- 35}, year = {1996}, language = {en} } @article{BorndoerferEisenblaetterGroetscheletal.1998, author = {Bornd{\"o}rfer, Ralf and Eisenbl{\"a}tter, Andreas and Gr{\"o}tschel, Martin and Martin, Alexander}, title = {Frequency assignment in cellular phone networks}, volume = {76}, journal = {Annals of Operations Research}, publisher = {J. C. Baltzer AG, Science Publishers}, doi = {10.1023/A:1018908907763}, pages = {73 -- 93}, year = {1998}, language = {en} } @article{GroetschelMartinWeismantel1996, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner trees: a cutting plane algorithm and computational results}, volume = {72}, journal = {Mathematical Programming, Series A}, number = {2}, doi = {10.1007/BF02592086}, pages = {125 -- 145}, year = {1996}, language = {en} } @article{GroetschelMartinWeismantel1997, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {The Steiner tree packing problem in VLSI design}, volume = {78}, journal = {Mathematical Programming}, number = {2}, pages = {265 -- 281}, year = {1997}, language = {en} } @inproceedings{BirkhoferFuegenschuhGuentheretal.2006, author = {Birkhofer, Herbert and F{\"u}genschuh, Armin and G{\"u}nther, Ute and Junglas, Daniel and Martin, Alexander and Sauer, Thorsten and Ulbrich, Stefan and W{\"a}ldele, Martin and Walter, Stephan}, title = {Topology- and shape-optimization of branched sheet metal products}, booktitle = {Operations Research Proceedings}, editor = {Haasis, Hans-Dietrich and Kopfer, Herbert and Sch{\"o}nberger, J{\"o}rn}, pages = {327 -- 336}, year = {2006}, language = {en} } @inproceedings{GroetschelMartinWeismantel1993, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Routing in grid graphs by cutting planes}, booktitle = {Integer Programming and Combinatorial Optimization. Proceedings of a Conference held at Centro Ettore Majorana, Erice, Italy, April 29 - May 1, 1993}, editor = {Rinaldi, Giovanni and Wolsey, Laurence}, publisher = {Librarian CORE}, address = {Louvain-la-Neuve}, pages = {447 -- 461}, year = {1993}, language = {en} } @inproceedings{BirkhoferFuegenschuhMartinetal.2007, author = {Birkhofer, Herbert and F{\"u}genschuh, Armin and Martin, Alexander and W{\"a}ldele, Martin}, title = {Algorithmenbasierte Produktentwicklung f{\"u}r integrale Blechbauweisen h{\"o}herer Verzweigungsordnung}, booktitle = {Optimierung in der Produktentwicklung, 5. Geimeinsames Kolloquium Konstruktionstechnik}, year = {2007}, language = {en} } @article{PfetschFuegenschuhGeissleretal.2014, author = {Pfetsch, Marc and F{\"u}genschuh, Armin and Geißler, Bj{\"o}rn and Geißler, Nina and Gollmer, Ralf and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Martin, Alexander and Morsi, Antonio and R{\"o}vekamp, Jessica and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Stangl, Claudia and Steinbach, Marc and Vigerske, Stefan and Willert, Bernhard}, title = {Validation of Nominations in Gas Network Optimization: Models, Methods, and Solutions}, journal = {Optimization Methods and Software}, publisher = {Taylor \& Francis}, doi = {10.1080/10556788.2014.888426}, year = {2014}, abstract = {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.}, language = {en} } @article{FuegenschuhGeisslerGollmeretal.2013, author = {F{\"u}genschuh, Armin and Geißler, Bj{\"o}rn and Gollmer, Ralf and Hayn, Christine and Henrion, Ren{\´e} and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Martin, Alexander and Mirkov, Radoslava and Morsi, Antonio and R{\"o}misch, Werner and R{\"o}vekamp, Jessica and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Stangl, Claudia and Steinbach, Marc and Willert, Bernhard}, title = {Mathematical optimization for challenging network planning problems in unbundled liberalized gas markets}, volume = {5}, journal = {Energy Systems}, number = {3}, publisher = {Springer Berlin Heidelberg}, address = {Berlin}, doi = {10.1007/s12667-013-0099-8}, pages = {449 -- 473}, year = {2013}, abstract = {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.}, language = {en} } @article{FerreiraGroetschelMartinetal.1993, author = {Ferreira, Carlos and Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert and Kiefl, Stefan and Krispenz, Ludwig}, title = {Some Integer Programs Arising in the Design of Main Frame Computers}, volume = {38}, journal = {ZOR - Methods and Models of Operations Research}, number = {1}, pages = {77 -- 100}, year = {1993}, language = {en} } @article{GroetschelMartinWeismantel1995, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Routing in Grid Graphs by Cutting Planes}, volume = {41}, journal = {ZOR - Mathematical Methods of Operations Research}, number = {3}, pages = {255 -- 275}, year = {1995}, language = {en} } @article{GroetschelMartinWeismantel1996, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner Trees: Separation Algorithms}, volume = {9}, journal = {SIAM Journal on Discrete Mathematics}, number = {2}, doi = {10.1137/S0895480193258716}, pages = {233 -- 257}, year = {1996}, language = {en} } @inproceedings{MartinGeisslerHeynetal.2011, author = {Martin, Alexander and Geißler, Bj{\"o}rn and Heyn, Christine and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Morsi, Antonio and Pfetsch, Marc and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Steinbach, Marc and Willert, Bernhard}, title = {Optimierung Technischer Kapazit{\"a}ten in Gasnetzen}, booktitle = {Optimierung in der Energiewirtschaft}, publisher = {VDI-Verlag, D{\"u}sseldorf}, pages = {105 -- 114}, year = {2011}, language = {en} } @article{GroetschelMartinWeismantel1996, author = {Gr{\"o}tschel, Martin and Martin, Alexander and Weismantel, Robert}, title = {Packing Steiner Trees: Further Facets}, volume = {17}, journal = {European Journal of Combinatorics}, number = {1}, doi = {10.1006/eujc.1996.0004}, pages = {39 -- 52}, year = {1996}, language = {en} } @misc{MartinGeisslerHaynetal.2012, author = {Martin, Alexander and Geißler, Bj{\"o}rn and Hayn, Christine and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Morsi, Antonio and Pfetsch, Marc and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Steinbach, Marc and Willert, Bernhard}, title = {Optimierung Technischer Kapazit{\"a}ten in Gasnetzen}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-15121}, year = {2012}, abstract = {Die mittel- und l{\"a}ngerfristige Planung f{\"u}r den Gastransport hat sich durch {\"A}nderungen 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 Kapazit{\"a}t und Topologieplanung bezeichnet werden. Diese mathematischen Optimierungsprobleme werden vorgestellt und L{\"o}sungsans{\"a}tze skizziert.}, language = {de} } @inproceedings{BorndoerferEisenblaetterGroetscheletal.1996, author = {Bornd{\"o}rfer, Ralf and Eisenbl{\"a}tter, Andreas and Gr{\"o}tschel, Martin and Martin, Alexander}, title = {Stable-Set and Other Techniques for Frequency Assignment Problems}, booktitle = {Anais da I Oficina Nacional em Problemas de Corte \& Empacotamento}, publisher = {Universidade de S{\~a}o Paulo, Instituto de Matem{\´a}tica e Estat{\´i}stica}, pages = {17 -- 21}, year = {1996}, language = {en} } @misc{FuegenschuhGeisslerGollmeretal.2013, author = {F{\"u}genschuh, Armin and Geißler, Bj{\"o}rn and Gollmer, Ralf and Hayn, Christine and Henrion, Rene and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Martin, Alexander and Mirkov, Radoslava and Morsi, Antonio and R{\"o}misch, Werner and R{\"o}vekamp, Jessica and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Stangl, Claudia and Steinbach, Marc and Willert, Bernhard}, title = {Mathematical Optimization for Challenging Network Planning Problems in Unbundled Liberalized Gas Markets}, issn = {1438-0064}, doi = {10.1007/s12667-013-0099-8}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-17821}, year = {2013}, abstract = {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.}, language = {en} } @misc{PfetschFuegenschuhGeissleretal.2012, author = {Pfetsch, Marc and F{\"u}genschuh, Armin and Geißler, Bj{\"o}rn and Geißler, Nina and Gollmer, Ralf and Hiller, Benjamin and Humpola, Jesco and Koch, Thorsten and Lehmann, Thomas and Martin, Alexander and Morsi, Antonio and R{\"o}vekamp, Jessica and Schewe, Lars and Schmidt, Martin and Schultz, R{\"u}diger and Schwarz, Robert and Schweiger, Jonas and Stangl, Claudia and Steinbach, Marc and Vigerske, Stefan and Willert, Bernhard}, title = {Validation of Nominations in Gas Network Optimization: Models, Methods, and Solutions}, issn = {1438-0064}, doi = {10.1080/10556788.2014.888426}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-16531}, year = {2012}, abstract = {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.}, language = {en} } @misc{AchterbergKochMartin2005, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {MIPLIB 2003}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-8625}, number = {05-28}, year = {2005}, abstract = {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.}, language = {en} } @article{MartinMuellerPokutta2014, author = {Martin, Alexander and M{\"u}ller, J. and Pokutta, Sebastian}, title = {Strict linear prices in non-convex European day-ahead electricity markets}, volume = {29}, journal = {Optimization Methods and Software}, number = {1}, pages = {189 -- 221}, year = {2014}, language = {en} } @book{GroetschelLovaszSchrijver1988, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Geometric Algorithms and Combinatorial Optimization}, volume = {2}, journal = {Algorithms and Combinatorics}, publisher = {Springer}, isbn = {3-540-13624-X, 0-387-13624-X (U.S.)}, year = {1988}, language = {en} } @inproceedings{GroetschelLovaszSchrijver1984, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Geometric Methods in Combinatorial Optimization}, booktitle = {Progress in Combinatorial Optimization, (Conference Waterloo/Ontario 1982)}, editor = {Pulleyblank, William}, publisher = {Academic Press}, pages = {167 -- 183}, year = {1984}, language = {en} } @incollection{GroetschelLovaszSchrijver1984, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Polynomial algorithms for perfect graphs}, volume = {21}, booktitle = {Topics on perfect graphs}, editor = {Berge, Claude and Chv{\´a}tal, Vašek}, publisher = {North-Holland}, pages = {325 -- 356}, year = {1984}, language = {en} } @article{GroetschelLovaszSchrijver1984, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Corrigendum to our paper "The ellipsoid method and its consequences in combinatorial optimization"}, volume = {4}, journal = {Combinatorica}, number = {4}, pages = {291 -- 295}, year = {1984}, language = {en} } @article{GroetschelLovaszSchrijver1986, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Relaxations of Vertex Packing}, volume = {40}, journal = {Journal of Combinatorial Theory, Series B}, pages = {330 -- 343}, year = {1986}, language = {en} } @article{GroetschelLovaszSchrijver1981, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {The ellipsoid method and its consequences in combinatorial optimization}, volume = {1}, journal = {Combinatorica}, number = {2}, pages = {169 -- 197}, year = {1981}, language = {en} } @article{GroetschelLovaszSchrijver1981, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {The ellipsoid method and its consequences in combinatorial optimization}, journal = {IIASA Collab. Proceedings Ser. CP-81-S1}, pages = {511 -- 546}, year = {1981}, language = {en} } @article{AchterbergKochMartin2006, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {MIPLIB 2003}, volume = {34}, journal = {Operations Research Letters}, number = {4}, publisher = {Elsevier / North-Holland}, doi = {10.1016/j.orl.2005.07.009}, pages = {361 -- 372}, year = {2006}, language = {en} } @inproceedings{EisenblaetterKochMartinetal.2003, author = {Eisenbl{\"a}tter, Andreas and Koch, Thorsten and Martin, Alexander and Achterberg, Tobias and F{\"u}genschuh, Armin and Koster, Arie M.C.A. and Wegel, Oliver and Wess{\"a}ly, Roland}, title = {Modelling Feasible Network Configurations for UMTS}, booktitle = {Telecommunications Network Design and Management}, editor = {Anandalingam, G. and Raghavan, S.}, publisher = {Kluver}, year = {2003}, language = {en} } @inproceedings{EisenblaetterFuegenschuhGeerdesetal.2003, author = {Eisenbl{\"a}tter, Andreas and F{\"u}genschuh, Armin and Geerdes, Hans-Florian and Junglas, Daniel and Koch, Thorsten and Martin, Alexander}, title = {Optimisation Methods for UMTS Radio Network Planning}, booktitle = {Operation Research Proceedings 2003}, editor = {Ahr, Dino and Fahrion, Roland and Oswald, Marcus and Reinelt, Gerhard}, publisher = {Springer}, doi = {10.1007/978-3-642-17022-5_5}, pages = {31 -- 38}, year = {2003}, language = {en} } @article{AchterbergKochMartin2005, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {Branching Rules Revisited}, volume = {33}, journal = {Operations Research Letters}, number = {1}, publisher = {Elsevier / North-Holland}, doi = {10.1016/j.orl.2004.04.002}, pages = {42 -- 54}, year = {2005}, language = {en} } @article{KochMartin1998, author = {Koch, Thorsten and Martin, Alexander}, title = {Solving Steiner tree problems in graphs to optimality}, volume = {32}, journal = {Networks}, doi = {10.1002/(SICI)1097-0037(199810)32:3\%3C207::AID-NET5\%3E3.0.CO;2-O}, pages = {207 -- 232}, year = {1998}, language = {en} } @incollection{KochMartinVoss2001, author = {Koch, Thorsten and Martin, Alexander and Voß, Stefan}, title = {SteinLib: An Updated Library on Steiner Tree Problems in Graphs}, booktitle = {Steiner Trees in Industry}, editor = {Du, D.-Z. and Cheng, X.}, publisher = {Kluwer}, doi = {10.1007/978-1-4613-0255-1_9}, pages = {285 -- 325}, year = {2001}, language = {en} } @article{FiedlerLeichtleKaseetal.2009, author = {Fiedler, Georg Martin and Leichtle, Alexander Benedikt and Kase, Julia and Baumann, Sven and Ceglarek, Uta and Felix, Klaus and Conrad, Tim and Witzigmann, Helmut and Weimann, Arved and Sch{\"u}tte, Christof and Hauss, Johann and B{\"u}chler, Markus and Thiery, Joachim}, title = {Serum Peptidome Profiling Revealed Platelet Factor 4 as a Potential Discriminating Peptide Associated With Pancreatic Cancer}, volume = {15}, journal = {Clinical Cancer Research}, number = {11}, publisher = {American Association for Cancer Research,}, doi = {10.1158/1078-0432.CCR-08-2701}, pages = {3812 -- 3819}, year = {2009}, language = {en} } @inproceedings{MartinMuellerPokutta2010, author = {Martin, Alexander and M{\"u}ller, J. and Pokutta, Sebastian}, title = {On clearing coupled day-ahead electricity markets}, booktitle = {Proceedings of 23rd Australasian Finance and Banking Conference}, year = {2010}, language = {en} } @inproceedings{HelmkeGluchshenkoMartinetal.2011, author = {Helmke, H. and Gluchshenko, O. and Martin, Alexander and Peter, A. and Pokutta, Sebastian and Siebert, U.}, title = {Optimal Mixed-Mode Runway Scheduling}, booktitle = {Proceedings of DACS}, year = {2011}, language = {en} } @misc{BorndoerferFerreiraMartin1997, author = {Bornd{\"o}rfer, Ralf and Ferreira, Carlos E. and Martin, Alexander}, title = {Matrix Decomposition by Branch-and-Cut}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2839}, number = {SC-97-14}, year = {1997}, abstract = {In this paper we investigate whether matrices arising from linear or integer programming problems can be decomposed into so-called {\em bordered block diagonal form}. More precisely, given some matrix \$A\$, we try to assign as many rows as possible to some number of blocks of limited size such that no two rows assigned to different blocks intersect in a common column. Bordered block diagonal form is desirable because it can guide and speed up the solution process for linear and integer programming problems. We show that various matrices from the \%LP- and MIP-libraries \Netlib{} and MIPLIB can indeed be decomposed into this form by computing optimal decompositions or decompositions with proven quality. These computations are done with a branch-and-cut algorithm based on polyhedral investigations of the matrix decomposition problem.}, language = {en} } @misc{BixbyMartin1996, author = {Bixby, Robert E. and Martin, Alexander}, title = {Parallelizing the Dual Simplex Method}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2112}, number = {SC-95-45}, year = {1996}, abstract = {We study the parallelization of the steepest-edge version of the dual simplex algorithm. Three different parallel implementations are examined, each of which is derived from the CPLEX dual simplex implementation. One alternative uses PVM, one general-purpose System V shared-memory constructs, and one the PowerC extension of C on a Silicon Graphics multi-processor. These versions were tested on different parallel platforms, including heterogeneous workstation clusters, Sun S20-502, Silicon Graphics multi-processors, and an IBM SP2. We report on our computational experience.}, language = {en} } @misc{DahlMartinStoer1995, author = {Dahl, Geir and Martin, Alexander and Stoer, Mechthild}, title = {Routing through virtual paths in layered telecommunication networks}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2070}, number = {SC-95-41}, year = {1995}, abstract = {We study a network configuration problem in telecommunications where one wants to set up paths in a capacitated network to accommodate given point-to-point traffic demand. The problem is formulated as an integer linear programming model where 0-1 variables represent different paths. An associated integral polytope is studied and different classes of facets are described. These results are used in a cutting plane algorithm. Computational results for some realistic problems are reported.}, language = {en} } @misc{KochMartin1996, author = {Koch, Thorsten and Martin, Alexander}, title = {Solving Steiner Tree Problems in Graphs to Optimality}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-2526}, number = {SC-96-42}, year = {1996}, abstract = {In this paper we present the implementation of a branch-and-cut algorithm for solving Steiner tree problems in graphs. Our algorithm is based on an integer programming formulation for directed graphs and comprises preprocessing, separation algorithms and primal heuristics. We are able to solve all problem instances discussed in literature to optimality, including one to our knowledge not yet solved problem. We also report on our computational experiences with some very large Steiner tree problems arising from the design of electronic circuits. All test problems are gathered in a newly introduced library called {\em SteinLib} that is accessible via World Wide Web.}, language = {en} } @misc{MartinWeismantel1993, author = {Martin, Alexander and Weismantel, Robert}, title = {Packing Paths and Steiner Trees: Routing of Electronic Circuits.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1113}, number = {SC-93-15}, year = {1993}, abstract = {One of the challenging problems in the design of electronic circuits is the so-called routing problem. Roughly speaking, the task is to connect so-called terminal sets via wires on a predefined area. In addition, certain design rules are to be taken into account and an objective function such as the wiring length must be minimized. The routing problem in general is too complex to be solved in one step. Depending on the user's choice of decomposing the chip design problem into a hierarchy of stages, on the underlying technology, and on the given design rules, various subproblems arise. We discuss several variants of practically relevant routing problems and give a short overview on the underlying technologies and design rules. Many of the routing problems that come up this way can be formulated as the problem of packing so-called Steiner trees in certain graphs. We consider the Steiner tree packing problem from a polyhedral point of view and present three possibilities to define an appropriate polyhedron. Weighing their pros and cons we decide for one of these polytopes and sketch some of our investigations.}, language = {en} } @misc{FerreiraMartinSouzaetal.1994, author = {Ferreira, Carlos E. and Martin, Alexander and Souza, Cid C. de and Weismantel, Robert and Wolsey, Laurence}, title = {Formulations and Valid Inequalities for the Node Capacitated Graph Partitioning Problem.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1450}, number = {SC-94-16}, year = {1994}, abstract = {We investigate the problem of partitioning the nodes of a graph under capacity restriction on the sum of the node weights in each subset of the partition. The objective is to minimize the sum of the costs of the edges between the subsets of the partition. This problem has a variety of applications, for instance in the design of electronic circuits and devices. We present alternative integer programming formulations for this problem and discuss the links between these formulations. Having chosen to work in the space of edges of the multicut, we investigate the convex hull of incidence vectors of feasible multicuts. In particular, several classes of inequalities are introduced, and their strength and robustness are analyzed as various problem parameters change.}, language = {en} } @misc{FerreiraMartinSouzaetal.1994, author = {Ferreira, Carlos E. and Martin, Alexander and Souza, Cid C. de and Weismantel, Robert and Wolsey, Laurence}, title = {The Node Capacitated Graph Partitioning Problem: A Computational Study.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1469}, number = {SC-94-17}, year = {1994}, abstract = {In this paper we consider the problem of \$k\$-partitioning the nodes of a graph with capacity restrictions on the sum of the node weights in each subset of the partition, and the objective of minimizing the sum of the costs of the edges between the subsets of the partition. Based on a study of valid inequalities, we present a variety of separation heuristics for so-called cycle, cycle with ears, knapsack tree and path-block-cycle inequalities. The separation heuristics, plus primal heuristics, have been implemented in a branch-and-cut routine using a formulation including the edges with nonzero costs and node variables. Results are presented for three classes of problems: equipartitioning problems arising in finite element methods and partitioning problems associated with electronic circuit layout and compiler design.}, language = {en} } @misc{WeismantelFerreiraMartin1993, author = {Weismantel, Robert and Ferreira, Carlos E. and Martin, Alexander}, title = {A Cutting Plane Based Algorithm for the Multiple Knapsack Problem.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1031}, number = {SC-93-07}, year = {1993}, abstract = {In this paper we describe a cutting plane based algorithm for the multiple knapsack problem. We use our algorithm to solve some practical problem instances arising in the layout of electronic circuits and in the design of main frame computers, and we report on our computational experience. This includes a discussion and evaluation of separation algorithms, an LP-based primal heuristic and some implementation details. The paper is based on the polyhedral theory for the multiple knapsack polytope developed in our companion paper SC 93-04 and meant to turn this theory into an algorithmic tool for the solution of practical problems.}, language = {en} } @misc{JuengerMartinReineltetal.1992, author = {J{\"u}nger, Michael and Martin, Alexander and Reinelt, Gerhard and Weismantel, Robert}, title = {Quadratic 0/1 Optimization and a Decomposition Approach for the Placement of Electronic Circuits.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-803}, number = {SC-92-10}, year = {1992}, abstract = {The placement in the layout design of electronic circiuts consists of finding a non- overlapping assignment of rectangular cells to positions on the chip so what wireability is guaranteed and certain technical constraints are met.This problem can be modelled as a quadratic 0/1- program subject to linear constraints. We will present a decomposition approach to the placement problem and give results about \$NP\$-hardness and the existence of \$\varepsilon\$-approximative algorithms for the involved optimization problems. A graphtheoretic formulation of these problems will enable us to develop approximative algorithms. Finally we will present details of the implementation of our approach and compare it to industrial state of the art placement routines. {\bf Keywords:} Quadratic 0/1 optimization, Computational Complexity, VLSI-Design.}, language = {en} } @misc{FerreiraMartinWeismantel1993, author = {Ferreira, Carlos E. and Martin, Alexander and Weismantel, Robert}, title = {Facets for the Multiple Knapsack Problem.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-1007}, number = {SC-93-04}, year = {1993}, abstract = {In this paper we consider the multiple knapsack problem which is defined as follows: given a set \$N\$ of items with weights \$f_i\$, \$i \in N\$, a set \$M\$ of knapsacks with capacities \$F_k\$, \$k \in M\$, and a profit function \$c_{ik}, i \in N, k \in M\$; find an assignment of a subset of the set of items to the set of knapsacks that yields maximum profit (or minimum cost). With every instance of this problem we associate a polyhedron whose vertices are in one to one correspondence to the feasible solutions of the instance. This polytope is the subject of our investigations. In particular, we present several new classes of inequalities and work out necessary and sufficient conditions under which the corresponding inequality defines a facet. Some of these conditions involve only properties of certain knapsack constraints, and hence, apply to the generalized assignment polytope as well. The results presented here serve as the theoretical basis for solving practical problems. The algorithmic side of our study, i.e., separation algorithms, implementation details and computational experience with a branch and cut algorithm are discussed in the companion paper SC 93-07.}, language = {en} } @misc{MartinWeismantel1998, author = {Martin, Alexander and Weismantel, Robert}, title = {Conjunctive Cuts for Integer Programs}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3618}, number = {SC-98-18}, year = {1998}, abstract = {This paper deals with a family of conjunctive inequalities. Such inequalities are needed to describe the polyhedron associated with all the integer points that satisfy several knapsack constraints simultaneously. Here we demonstrate the strength and potential of conjunctive inequalities in connection with lifting from a computational point of view.}, language = {en} } @misc{MartinWeismantel1997, author = {Martin, Alexander and Weismantel, Robert}, title = {Contributions to General Mixed Integer Knapsack Problems}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3075}, number = {SC-97-38}, year = {1997}, abstract = {This paper deals with a general mixed integer knapsack polyhedron for which we introduce and analyze a new family of inequalities. We discuss the value of this family both from a theoretic and a computational point of view.}, language = {en} } @article{GamrathGleixnerKochetal.2019, author = {Gamrath, Gerald and Gleixner, Ambros and Koch, Thorsten and Miltenberger, Matthias and Kniasew, Dimitri and Schl{\"o}gel, Dominik and Martin, Alexander and Weninger, Dieter}, title = {Tackling Industrial-Scale Supply Chain Problems by Mixed-Integer Programming}, volume = {37}, journal = {Journal of Computational Mathematics}, doi = {10.4208/jcm.1905-m2019-0055}, pages = {866 -- 888}, year = {2019}, abstract = {The modeling flexibility and the optimality guarantees provided by mixed-integer programming greatly aid the design of robust and future-proof decision support systems. The complexity of industrial-scale supply chain optimization, however, often poses limits to the application of general mixed-integer programming solvers. In this paper we describe algorithmic innovations that help to ensure that MIP solver performance matches the complexity of the large supply chain problems and tight time limits encountered in practice. Our computational evaluation is based on a diverse set, modeling real-world scenarios supplied by our industry partner SAP.}, language = {en} } @misc{GamrathKochMartinetal.2013, author = {Gamrath, Gerald and Koch, Thorsten and Martin, Alexander and Miltenberger, Matthias and Weninger, Dieter}, title = {Progress in Presolving for Mixed Integer Programming}, issn = {1438-0064}, doi = {10.1007/s12532-015-0083-5}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-42530}, year = {2013}, abstract = {Presolving attempts to eliminate redundant information from the problem formulation and simultaneously tries to strengthen the formulation. It can be very effective and is often essential for solving instances. Especially for mixed integer programming problems, fast and effective presolving algorithms are very important. In this paper, we report on three new presolving techniques. The first method searches for singleton continuous columns and tries to fix the corresponding variables. Then we present a presolving technique which exploits a partial order of the variables to induce fixings. Finally, we show an approach based on connected components in graphs. Our computational results confirm the profitable use of the algorithms in practice.}, language = {en} } @misc{KochMartinVoss2000, author = {Koch, Thorsten and Martin, Alexander and Voß, Stefan}, title = {SteinLib: An Updated Library on Steiner Tree Problems in Graphs}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6056}, number = {00-37}, year = {2000}, abstract = {In this paper we present the {\em SteinLib}, a library of data sets for the Steiner tree problem in graphs. This library extends former libraries on Steiner tree problems by many new interesting and difficult instances, most of them arising from real-world applications. We give a survey on the difficulty of these problem instances by giving references to state-of-the-art software packages that were the first or are currently among the best to solve these instances.}, language = {en} } @misc{EisenblaetterFuegenschuhKochetal.2002, author = {Eisenbl{\"a}tter, Andreas and F{\"u}genschuh, Armin and Koch, Thorsten and Koster, Arie M.C.A. and Martin, Alexander and Pfender, Tobias and Wegel, Oliver and Wess{\"a}ly, Roland}, title = {Modelling Feasible Network Configurations for UMTS}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6837}, number = {02-16}, year = {2002}, abstract = {A model for the optimisation of the location and configuration of base stations in a UMTS network is described. The focus is primarily on modelling the configuration problem sufficiently accurate using mixed-integer variables and (essentially) linear constraints. These constraints reflect the limited downlink code capacity in each cell, the interference limitations for successful up- and downlink transmissions, the need for sufficiently strong (cell) pilot signals, and the potential gain for mobiles from being in soft(er) hand-over. It is also explained how to use the model as a basis for rating network configurations.}, language = {en} } @misc{AchterbergKochMartin2002, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {Branching on History Information}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6990}, number = {02-32}, year = {2002}, abstract = {Mixed integer programs (\$MIPs\$) are commonly solved with branch and bound algorithms based on linear programming. The success and the speed of the algorithm strongly depends on the strategy used to select the branching variables. Today's state-of-the-art strategy is called \emph{pseudocost branching} and uses information of previous branchings to determine the current branching. We propose a modification of \emph{pseudocost branching} which we call \emph{history branching}. This strategy has been implemented in \$SIP\$, a state-of-the-art \$MIP\$ solver. We give computational results that show the superiority of the new strategy.}, language = {en} } @misc{EisenblaetterFuegenschuhGeerdesetal.2003, author = {Eisenbl{\"a}tter, Andreas and F{\"u}genschuh, Armin and Geerdes, Hans-Florian and Junglas, Daniel and Koch, Thorsten and Martin, Alexander}, title = {Optimization Methods for UMTS Radio Network Planning}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-7637}, number = {03-41}, year = {2003}, abstract = {The UMTS radio network planning problem poses the challenge of designing a cost-effective network that provides users with sufficient coverage and capacity. We describe an optimization model for this problem that is based on comprehensive planning data of the EU project MOMENTUM. We present heuristic mathematical methods for this realistic model, including computational results.}, language = {en} } @phdthesis{Martin1992, author = {Martin, Alexander}, title = {Packen von Steinerb{\"a}umen: Polyedrische Studien und Anwendung.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-4894}, number = {TR-92-04}, year = {1992}, abstract = {Gegeben sei ein Graph \$G=(V,E)\$ mit positiven Kantenkapazit{\"a}ten \$c_e\$ und Knotenmengen \$T_1,\ldots,T_N\$. Das Steinerbaumpackungs-Problem besteht darin, Kantenmengen \$S_1,\ldots,S_N\$ zu finden, so da\ss\ jedes \$S_k\$ die Knoten aus \$T_k\$ verbindet und jede Kante \$e\$ in h{\"o}chstens \$c_e\$ Kantenmengen aus \$S_1,\ldots,S_N\$ vorkommt. Eine zul{\"a}ssige L{\"o}sung dieses Problems nennen wir eine Steinerbaumpackung. Ist zus{\"a}tzlich eine Gewichtung der Kanten gegeben und nach einer bez{\"u}glich dieser Gewichtung minimalen Steinerbaumpackung gesucht, so sprechen wir vom gewichteten Steinerbaumpackungs-Problem. Die Motivation zum Studium dieses Problems kommt aus dem Entwurf elektronischer Schaltungen. Ein dort auftretendes Teilproblem ist das sogenannte Verdrahtungsproblem, das im wesentlichen darin besteht, gegebene Punktmengen unter bestimmten Nebenbedingungen und Optimalit{\"a}tskriterien auf einer Grundfl{\"a}che zu verbinden. Wir studieren das Steinerbaumpackungs-Problem aus polyedrischer Sicht und definieren ein Polyeder, dessen Ecken genau den Steinerbaumpackungen entsprechen. Anschlie\ss end versuchen wir, dieses Polyeder durch gute'' beziehungsweise facetten-definierenden Ungleichungen zu beschreiben. Basierend auf diesen Ungleichungen entwickeln wir ein Schnittebenenverfahren. Die L{\"o}sung des Schnittebenenverfahrens liefert eine untere Schranke f{\"u}r die Optimall{\"o}sung und dient als Grundlage f{\"u}r die Entwicklung guter Primalheuristiken. Wir haben das von uns implementierte Schnittebenenverfahren an einem Spezialfall des Verdrahtungsproblems, dem sogenannten Switchbox-Verdrahtungsproblem, getestet und vielversprechende Ergebnisse erzielt.}, language = {de} } @misc{MarchandMartinWeismanteletal.1999, author = {Marchand, Hugues and Martin, Alexander and Weismantel, Robert and Wolsey, Laurence}, title = {Cutting Planes in Integer and Mixed Integer Programming}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-4339}, number = {SC-99-44}, year = {1999}, abstract = {This survey presents cutting planes that are useful or potentially useful in solving mixed integer programs. Valid inequalities for i) general integer programs, ii) problems with local structure such as knapsack constraints, and iii) problems with 0-1 coefficient matrices, such as set packing, are examined in turn. Finally the use of valid inequalities for classes of problems with structure, such as network design, is explored.}, language = {en} } @misc{MartinWeismantel1997, author = {Martin, Alexander and Weismantel, Robert}, title = {The Intersection of Knapsack Polyhedra and Extensions}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3300}, number = {SC-97-61}, year = {1997}, abstract = {This paper introduces a scheme of deriving strong cutting planes for a general integer programming problem. The scheme is related to Chvatal-Gomory cutting planes and important special cases such as odd hole and clique inequalities for the stable set polyhedron or families of inequalities for the knapsack polyhedron. We analyze how relations between covering and incomparability numbers associated with the matrix can be used to bound coefficients in these inequalities. For the intersection of several knapsack polyhedra, incomparabilities between the column vectors of the associated matrix will be shown to transfer into inequalities of the associated polyhedron. Our scheme has been incorporated into the mixed integer programming code SIP. About experimental results will be reported.}, language = {en} } @misc{AchterbergKochMartin2004, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {Branching rules revisited}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-7886}, number = {04-13}, year = {2004}, abstract = {Mixed integer programs are commonly solved with linear programming based branch-and-bound algorithms. The success of the algorithm strongly depends on the strategy used to select the variable to branch on. We present a new generalization called {\sl reliability branching} of today's state-of-the-art {\sl strong branching} and {\sl pseudocost branching} strategies for linear programming based branch-and-bound algorithms. After reviewing commonly used branching strategies and performing extensive computational studies we compare different parameter settings and show the superiority of our proposed newstrategy.}, language = {en} } @misc{EisenblaetterGeerdesKochetal.2004, author = {Eisenbl{\"a}tter, Andreas and Geerdes, Hans-Florian and Koch, Thorsten and Martin, Alexander and Wess{\"a}ly, Roland}, title = {UMTS Radio Network Evaluation and Optimization beyond Snapshots}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-7903}, number = {04-15}, year = {2004}, abstract = {This paper is concerned with UMTS radio network design. Our task is to reconfigure antennas and the related cells as to improve network quality. In contrast to second generation GSM networks, \emph{interference} plays a paramount role when designing third generation radio networks. A known compact formulation for assessing the interference characteristics of a radio network as coupling relations between cells based on user snapshots is generalized to statistical average load. This enables us to overcome the notorious difficulties of snapshot-based network optimization approaches. We recall a mixed-integer programming model for the network design problem that is based on user snapshots and contrast it with a new network design model based on the average coupling formulation. Exemplarily focusing on the important problem of optimizing antenna tilts, we give computational results for a fast local search algorithm and the application of a MIP solver to both models. These results demonstrate that our new average-based approaches outperform state-of-the-art snapshot models for UMTS radio network optimization.}, language = {en} } @article{ConradLeichtleCeglareketal.2013, author = {Conrad, Tim and Leichtle, Alexander Benedikt and Ceglarek, Uta and Weinert, P. and Nakas, C.T. and Nuoffer, Jean-Marc and Kase, Julia and Witzigmann, Helmut and Thiery, Joachim and Fiedler, Georg Martin}, title = {Pancreatic carcinoma, pancreatitis, and healthy controls - metabolite models in a three-class diagnostic dilemma}, volume = {9}, journal = {Metabolomics}, number = {3}, doi = {10.1007/s11306-012-0476-7}, pages = {677 -- 687}, year = {2013}, abstract = {Background: Metabolomics as one of the most rapidly growing technologies in the ?-omics?field denotes the comprehensive analysis of low molecular-weight compounds and their pathways. Cancer-specific alterations of the metabolome can be detected by high-throughput massspectrometric metabolite profiling and serve as a considerable source of new markers for the early differentiation of malignant diseases as well as their distinction from benign states. However, a comprehensive framework for the statistical evaluation of marker panels in a multi-class setting has not yet been established. Methods: We collected serum samples of 40 pancreatic carcinoma patients, 40 controls, and 23 pancreatitis patients according to standard protocols and generated amino acid profiles by routine mass-spectrometry. In an intrinsic three-class bioinformatic approach we compared these profiles, evaluated their selectivity and computed multi-marker panels combined with the conventional tumor marker CA 19-9. Additionally, we tested for non-inferiority and superiority to determine the diagnostic surplus value of our multi-metabolite marker panels.  Results: Compared to CA 19-9 alone, the combined amino acid-based metabolite panel had a superior selectivity for the discrimination of healthy controls, pancreatitis, and pancreatic carcinoma patients [Volume under ROC surface (VUS) = 0.891 (95\\% CI 0.794 - 0.968)]. Conclusions: We combined highly standardized samples, a three-class study design, a highthroughput mass-spectrometric technique, and a comprehensive bioinformatic framework to identify metabolite panels selective for all three groups in a single approach. Our results suggest that metabolomic profiling necessitates appropriate evaluation strategies and ?despite all its current limitations? can deliver marker panels with high selectivity even in multi-class settings.}, language = {en} } @article{ConradLeichtleNuofferetal.2012, author = {Conrad, Tim and Leichtle, Alexander Benedikt and Nuoffer, Jean-Marc and Ceglarek, Uta and Kase, Julia and Witzigmann, Helmut and Thiery, Joachim and Fiedler, Georg Martin}, title = {Serum amino acid profiles and their alterations in colorectal cancer}, journal = {Metabolomics}, doi = {10.1007/s11306-011-0357-5}, year = {2012}, abstract = {Mass spectrometry-based serum metabolic profiling is a promising tool to analyse complex cancer associated metabolic alterations, which may broaden our pathophysiological understanding of the disease and may function as a source of new cancer-associated biomarkers. Highly standardized serum samples of patients suffering from colon cancer (n = 59) and controls (n = 58) were collected at the University Hospital Leipzig. We based our investigations on amino acid screening profiles using electrospray tandem-mass spectrometry. Metabolic profiles were evaluated using the Analyst 1.4.2 software. General, comparative and equivalence statistics were performed by R 2.12.2. 11 out of 26 serum amino acid concentrations were significantly different between colorectal cancer patients and healthy controls. We found a model including CEA, glycine, and tyrosine as best discriminating and superior to CEA alone with an AUROC of 0.878 (95\\% CI 0.815?0.941). Our serum metabolic profiling in colon cancer revealed multiple significant disease-associated alterations in the amino acid profile with promising diagnostic power. Further large-scale studies are necessary to elucidate the potential of our model also to discriminate between cancer and potential differential diagnoses. In conclusion, serum glycine and tyrosine in combination with CEA are superior to CEA for the discrimination between colorectal cancer patients and controls.}, language = {en} } @article{ConradGenzelCvetkovicetal.2017, author = {Conrad, Tim and Genzel, Martin and Cvetkovic, Nada and Wulkow, Niklas and Leichtle, Alexander Benedikt and Vybiral, Jan and Kytyniok, Gitta and Sch{\"u}tte, Christof}, title = {Sparse Proteomics Analysis - a compressed sensing-based approach for feature selection and classification of high-dimensional proteomics mass spectrometry data}, volume = {18}, journal = {BMC Bioinfomatics}, number = {160}, doi = {10.1186/s12859-017-1565-4}, year = {2017}, abstract = {Background: High-throughput proteomics techniques, such as mass spectrometry (MS)-based approaches, produce very high-dimensional data-sets. In a clinical setting one is often interested in how mass spectra differ between patients of different classes, for example spectra from healthy patients vs. spectra from patients having a particular disease. Machine learning algorithms are needed to (a) identify these discriminating features and (b) classify unknown spectra based on this feature set. Since the acquired data is usually noisy, the algorithms should be robust against noise and outliers, while the identified feature set should be as small as possible. Results: We present a new algorithm, Sparse Proteomics Analysis (SPA),based on thet heory of compressed sensing that allows us to identify a minimal discriminating set of features from mass spectrometry data-sets. We show (1) how our method performs on artificial and real-world data-sets, (2) that its performance is competitive with standard (and widely used) algorithms for analyzing proteomics data, and (3) that it is robust against random and systematic noise. We further demonstrate the applicability of our algorithm to two previously published clinical data-sets.}, language = {en} } @article{WilsonAnglinAmbellanetal.2017, author = {Wilson, David and Anglin, Carolyn and Ambellan, Felix and Grewe, Carl Martin and Tack, Alexander and Lamecker, Hans and Dunbar, Michael and Zachow, Stefan}, title = {Validation of three-dimensional models of the distal femur created from surgical navigation point cloud data for intraoperative and postoperative analysis of total knee arthroplasty}, volume = {12}, journal = {International Journal of Computer Assisted Radiology and Surgery}, number = {12}, publisher = {Springer}, doi = {10.1007/s11548-017-1630-5}, pages = {2097 -- 2105}, year = {2017}, abstract = {Purpose: Despite the success of total knee arthroplasty there continues to be a significant proportion of patients who are dissatisfied. One explanation may be a shape mismatch between pre and post-operative distal femurs. The purpose of this study was to investigate a method to match a statistical shape model (SSM) to intra-operatively acquired point cloud data from a surgical navigation system, and to validate it against the pre-operative magnetic resonance imaging (MRI) data from the same patients. Methods: A total of 10 patients who underwent navigated total knee arthroplasty also had an MRI scan less than 2 months pre-operatively. The standard surgical protocol was followed which included partial digitization of the distal femur. Two different methods were employed to fit the SSM to the digitized point cloud data, based on (1) Iterative Closest Points (ICP) and (2) Gaussian Mixture Models (GMM). The available MRI data were manually segmented and the reconstructed three-dimensional surfaces used as ground truth against which the statistical shape model fit was compared. Results: For both approaches, the difference between the statistical shape model-generated femur and the surface generated from MRI segmentation averaged less than 1.7 mm, with maximum errors occurring in less clinically important areas. Conclusion: The results demonstrated good correspondence with the distal femoral morphology even in cases of sparse data sets. Application of this technique will allow for measurement of mismatch between pre and post-operative femurs retrospectively on any case done using the surgical navigation system and could be integrated into the surgical navigation unit to provide real-time feedback.}, language = {en} } @inproceedings{WeinholdLackorzynskiBierbaumetal.2016, author = {Weinhold, Carsten and Lackorzynski, Adam and Bierbaum, Jan and K{\"u}ttler, Martin and Planeta, Maksym and H{\"a}rtig, Hermann and Shiloh, Amnon and Levy, Ely and Ben-Nun, Tal and Barak, Amnon and Steinke, Thomas and Sch{\"u}tt, Thorsten and Fajerski, Jan and Reinefeld, Alexander and Lieber, Matthias and Nagel, Wolfgang}, title = {FFMK: A Fast and Fault-tolerant Microkernel-based System for Exascale Computing}, booktitle = {SPPEXA Symposium 2016}, doi = {10.1007/978-3-319-40528-5_18}, year = {2016}, language = {en} } @article{HeidaSikorskiWeber2022, author = {Heida, Martin and Sikorski, Alexander and Weber, Marcus}, title = {Consistency and order 1 convergence of cell-centered finite volume discretizations of degenerate elliptic problems in any space dimension}, journal = {SIAM Journal on Numerical Analysis}, doi = {10.20347/WIAS.PREPRINT.2913}, year = {2022}, abstract = {We study consistency of cell-centered finite difference methods for elliptic equations with degenerate coefficients in any space dimension \$d \geq 2\$. This results in order of convergence estimates in the natural weighted energy norm and in the weighted discrete \$L^2\$-norm on admissible meshes. The cells of meshes under consideration may be very irregular in size. We particularly allow the size of certain cells to remain bounded from below even in the asymptotic limit. For uniform meshes we show that the order of convergence is at least 1 in the energy semi-norm, provided the discrete and continuous solutions exist and the continuous solution has \$H^2\$ regularity.}, language = {en} } @article{SikorskiHeida2024, author = {Sikorski, Alexander and Heida, Martin}, title = {Voronoi Graph - Improved raycasting and integration schemes for high dimensional Voronoi diagrams}, arxiv = {http://arxiv.org/abs/2405.10050}, year = {2024}, abstract = {The computation of Voronoi Diagrams, or their dual Delauney triangulations is difficult in high dimensions. In a recent publication Polianskii and Pokorny propose an iterative randomized algorithm facilitating the approximation of Voronoi tesselations in high dimensions. In this paper, we provide an improved vertex search method that is not only exact but even faster than the bisection method that was previously recommended. Building on this we also provide a depth-first graph-traversal algorithm which allows us to compute the entire Voronoi diagram. This enables us to compare the outcomes with those of classical algorithms like qHull, which we either match or marginally beat in terms of computation time. We furthermore show how the raycasting algorithm naturally lends to a Monte Carlo approximation for the volume and boundary integrals of the Voronoi cells, both of which are of importance for finite Volume methods. We compare the Monte-Carlo methods to the exact polygonal integration, as well as a hybrid approximation scheme.}, language = {en} } @article{XieGruberCrampenetal.2025, author = {Xie, Kunpeng and Gruber, Lennart Johannes and Crampen, Martin and Li, Yao and Ferreira, Andr{\´e} and Tappeiner, Elias and Gillot, Maxime and Schepers, Jan and Xu, Jiangchang and Pankert, Tobias and Beyer, Michel and Shahamiri, Negar and ten Brink, Reinier and Dot, Gauthier and Weschke, Charlotte and van Nistelrooij, Niels and Verhelst, Pieter-Jan and Guo, Yan and Xu, Zhibin and Bienzeisler, Jonas and Rashad, Ashkan and Fl{\"u}gge, Tabea and Cotton, Ross and Vinayahalingam, Shankeeth and Ilesan, Robert and Raith, Stefan and Madsen, Dennis and Seibold, Constantin and Xi, Tong and Berg{\´e}, Stefaan and Nebelung, Sven and Kodym, Oldřich and Sundqvist, Osku and Thieringer, Florian and Lamecker, Hans and Coppens, Antoine and Potrusil, Thomas and Kraeima, Joep and Witjes, Max and Wu, Guomin and Chen, Xiaojun and Lambrechts, Adriaan and Cevidanes, Lucia H Soares and Zachow, Stefan and Hermans, Alexander and Truhn, Daniel and Alves, Victor and Egger, Jan and R{\"o}hrig, Rainer and H{\"o}lzle, Frank and Puladi, Behrus}, title = {Beyond Benchmarks: Towards Robust Artificial Intelligence Bone Segmentation in Socio-Technical Systems}, volume = {299}, journal = {Expert Systems With Applications}, number = {Part D}, doi = {10.1016/j.eswa.2025.130031}, year = {2025}, abstract = {Despite the advances in automated medical image segmentation, AI models still underperform in various clinical settings, challenging real-world integration. In this multicenter evaluation, we analyzed 20 state-of-the-art mandibular segmentation models across 19,218 segmentations of 1,000 clinically resampled CT/CBCT scans. We show that segmentation accuracy varies by up to 25\% depending on socio-technical factors such as voxel size, bone orientation, and patient conditions such as osteosynthesis or pathology. Higher sharpness, isotropic smaller voxels, and neutral orientation significantly improved results, while metallic osteosynthesis and anatomical complexity led to significant degradation. Our findings challenge the common view of AI models as "plug-and-play" tools and suggest evidence-based optimization recommendations for both clinicians and developers. This will in turn boost the integration of AI segmentation tools in routine healthcare.}, language = {en} } @article{BaermannMartinPokuttaetal.2018, author = {B{\"a}rmann, Andreas and Martin, Alexander and Pokutta, Sebastian and Schneider, Oskar}, title = {An Online-Learning Approach to Inverse Optimization}, year = {2018}, language = {en} } @article{EisenblaetterGeerdesKochetal.2005, author = {Eisenbl{\"a}tter, Andreas and Geerdes, Hans-Florian and Koch, Thorsten and Martin, Alexander and Wess{\"a}ly, Roland}, title = {UMTS Radio Network Evaluation and Optimization beyond Snapshots}, volume = {63}, journal = {Mathematical Methods of Operations Research}, number = {1}, doi = {10.1007/s00186-005-0002-z}, pages = {1 -- 29}, year = {2005}, language = {en} } @inproceedings{FuegenschuhHessMartinetal.2007, author = {F{\"u}genschuh, Armin and Hess, Wolfgang and Martin, Alexander and Ulbrich, Stefan}, title = {Diskrete und kontinuierliche Modelle zur Topologie- und Geometrie-Optimierung von Blechprofilen}, booktitle = {Sonderforschungsbereich 666}, editor = {Groche, P.}, pages = {37 -- 47}, year = {2007}, language = {en} } @book{GroetschelLovaszSchrijver1993, author = {Gr{\"o}tschel, Martin and Lov{\´a}sz, L{\´a}szlo and Schrijver, Alexander}, title = {Geometric Algorithms and Combinatorial Optimization}, volume = {2}, journal = {Algorithms and Combinatorics}, edition = {Second corrected edition}, publisher = {Springer}, isbn = {3-540-56740-2, 0-387-56740-2 (U.S.)}, year = {1993}, language = {en} } @incollection{EisenblaetterFuegenschuhKochetal.2002, author = {Eisenbl{\"a}tter, Andreas and F{\"u}genschuh, Armin and Koch, Thorsten and Koster, Arie M.C.A. and Martin, Alexander and Pfender, Tobias and Wegel, Oliver and Wess{\"a}ly, Roland}, title = {Mathematical Model of Feasible Network Configurations for UMTS}, booktitle = {Telecommunications network design and management}, editor = {G. Anandalingam, S.}, publisher = {Kluwer}, pages = {1 -- 24}, year = {2002}, language = {en} } @inproceedings{FuegenschuhMartinStoeveken2004, author = {F{\"u}genschuh, Armin and Martin, Alexander and St{\"o}veken, Peter}, title = {Integrated Optimization of School Starting Times and Public Bus Services}, booktitle = {Mathematics in the Supply Chain}, editor = {Bixby, Robert E. and Simchi-Levi, D. and Martin, Alexander and Zimmermann, U.}, year = {2004}, language = {en} } @inproceedings{EisenblaetterFuegenschuhGeerdesetal.2004, author = {Eisenbl{\"a}tter, Andreas and F{\"u}genschuh, Armin and Geerdes, Hans-Florian and Junglas, Daniel and Koch, Thorsten and Martin, Alexander}, title = {Integer Programming Methods for UMTS Radio Network Planning}, booktitle = {Proceedings of the WiOpt'04, Cambridge, UK}, year = {2004}, language = {en} } @incollection{FuegenschuhMartin2005, author = {F{\"u}genschuh, Armin and Martin, Alexander}, title = {Computational Integer Programming and Cutting Planes}, booktitle = {Handbooks in Operations Research and Management Science, Vol. 12}, editor = {Aardal, Karen I. and Nemhauser, George and Weismantel, R.}, publisher = {North-Holland}, pages = {69 -- 122}, year = {2005}, language = {en} } @inproceedings{FuegenschuhHomfeldHucketal.2006, author = {F{\"u}genschuh, Armin and Homfeld, Henning and Huck, Andreas and Martin, Alexander}, title = {Locomotive and Wagon Scheduling in Freight Transport}, booktitle = {Proceedings of the ATMOS06}, editor = {Jacob, R. and M{\"u}ller-Hannemann, Matthias}, year = {2006}, language = {en} } @inproceedings{FuegenschuhMartinMehlertetal.2005, author = {F{\"u}genschuh, Armin and Martin, Alexander and Mehlert, Christian and St{\"o}veken, Peter}, title = {Ein Planungstool zur Schulzeitstaffelung}, booktitle = {Supply Chain Management und Logistik}, editor = {G{\"u}nther, H.-O. and Mattfeld, D. and Suhl, L.}, pages = {419 -- 436}, year = {2005}, language = {en} } @inproceedings{FuegenschuhMartinStoeveken2005, author = {F{\"u}genschuh, Armin and Martin, Alexander and St{\"o}veken, Peter}, title = {Integrated Optimization of School Starting Times and Public Bus Services}, booktitle = {Operations Research Proceedings}, editor = {Fleuren, Hein and den Hertog, Dick and Kort, Peter}, pages = {150 -- 157}, year = {2005}, language = {en} }