Publications


Click here to see my pubs on Mendeley

Student Doctoral Dissertations

Software

  • T. K. et.al. Ralphs, COIN-OR Optimization Suite, COR@L Laboratory, Lehigh University. [Software] [DOI] [Bibtex]
    @Misc{ **key*,
    author  = {et.al. Ralphs, T.K.},
    doi = {10.5281/zenodo.246111},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{COIN-OR Optimization Suite}},
    software  = {https://github.com/coin-or/COIN-OR-OptimizationSuite}
    }
  • A. Bulut and T. K. Ralphs, OSi-CONIC, COR@L Laboratory, Lehigh University, 2016. [Software] [Bibtex]
    @Misc{ BulRal16,
    author  = {Bulut, A. and Ralphs, T.K.},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{OSi-CONIC}},
    software  = {https://github.com/aykutbulut/OSI-CONIC},
    year = {2016}
    }
  • M. V. Galati, T. K. Ralphs, and J. Wang, Dip Version 0.92, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ GalRalWan16,
    author  = {Galati, M.V. and Ralphs, T.K. and Wang, J.},
    doi = {10.5281/zenodo.246087},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{Dip Version 0.92}},
    software  = {http://projects.coin-or.org/Dip},
    year = {2016}
    }
  • A. Bulut and T. K. Ralphs, COLA, COR@L Laboratory, Lehigh University, 2016. [Software] [Bibtex]
    @Misc{ BulRal16-1,
    author  = {Bulut, A. and Ralphs, T.K.},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{COLA}},
    software  = {https://github.com/aykutbulut/COLA},
    year = {2016}
    }
  • T. K. Ralphs, CuPPy Version 0.7, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ Ral16,
    author  = {Ralphs, T.K.},
    doi = {10.5281/zenodo.245577},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{CuPPy Version 0.7}},
    software  = {https://github.com/tkralphs/CuPPy},
    year = {2016}
    }
  • A. Bulut and T. K. Ralphs, CGL-CONIC, COR@L Laboratory, Lehigh University, 2016. [Software] [Bibtex]
    @Misc{ BulRal16-2,
    author  = {Bulut, A. and Ralphs, T.K.},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{CGL-CONIC}},
    software  = {https://github.com/aykutbulut/CGL-CONIC},
    year = {2016}
    }
  • S. T. DeNegre, T. K. Ralphs, and S. A. Tahernejad, MiBS Version 0.95, COR@L Laboratory, Lehigh University, 2017. [Software] [DOI] [Bibtex]
    @Misc{ DeNRalTah17,
    author  = {DeNegre, S.T. and Ralphs, T.K. and Tahernejad, S.A.},
    doi = {10.5281/zenodo.556749},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{MiBS Version 0.95}},
    software  = {https://github.com/tkralphs/MiBS},
    year = {2017}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M. J. Saltzman, BLIS Version 0.94, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ XuRalLadSal16,
    author  = {Xu, Y. and Ralphs, T.K. and Lad{\'a}nyi, L. and Saltzman,
    M.J.},
    doi = {10.5281/zenodo.246079},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{BLIS Version 0.94}},
    software  = {https://projects.coin-or.org/CHiPPS},
    year = {2016}
    }
  • T. K. Ralphs, M. Guzelsoy, and A. Mahajan, SYMPHONY Version 5.6, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ RalGuzMah16,
    author  = {Ralphs, T.K. and Guzelsoy, M. and Mahajan, A.},
    doi = {10.5281/zenodo.248734},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.6}},
    software  = {https://projects.coin-or.org/SYMPHONY/},
    year = {2016}
    }
  • T. K. Ralphs, S. Vigerske, and A. Waechter, COIN-OR Build Tools, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ RalVigWae16,
    author  = {Ralphs, T.K. and Vigerske, S. and Waechter, A.},
    doi = {10.5281/zenodo.246124},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{COIN-OR Build Tools}},
    software  = {https://github.com/coin-or-tools/BuildTools/},
    year = {2016}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M. J. Saltzman, BiCEPs Version 0.94, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ XuRalLadSal16-1,
    author  = {Xu, Y. and Ralphs, T.K. and Lad{\'a}nyi, L. and Saltzman,
    M.J.},
    doi = {10.5281/zenodo.245652},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{BiCEPs Version 0.94}},
    software  = {https://projects.coin-or.org/CHiPPS},
    year = {2016}
    }
  • T. K. Ralphs and A. Bulut, GrUMPy Version 0.85, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ RalBul16,
    author  = {Ralphs, T.K. and Bulut, A.},
    doi = {https://doi.org/10.5281/zenodo.245613},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{GrUMPy Version 0.85}},
    software  = {https://github.com/tkralphs/GrUMPy},
    year = {2016}
    }
  • T. K. Ralphs and A. Bulut, GiMPy Version 1.3, COR@L Laboratory, Lehigh University, 2017. [Software] [DOI] [Bibtex]
    @Misc{ RalBul17,
    author  = {Ralphs, T.K. and Bulut, A.},
    doi = {10.5281/zenodo.1039834},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{GiMPy Version 1.3}},
    software  = {https://github.com/tkralphs/GiMPy},
    year = {2017}
    }
  • T. K. Ralphs and A. Bulut, BLImPy Version 1.3, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ RalBul16-1,
    author  = {Ralphs, T.K. and Bulut, A.},
    doi = {10.5281/zenodo.252673},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{BLImPy Version 1.3}},
    software  = {https://github.com/tkralphs/BLImPy},
    year = {2016}
    }
  • A. Bulut and T. K. Ralphs, DisCO Version 0.95, COR@L Laboratory, Lehigh University, 2017. [Software] [DOI] [Bibtex]
    @Misc{ BulRal17,
    author  = {Bulut, A. and Ralphs, T.K.},
    doi = {10.5281/zenodo.237107},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{DisCO Version 0.95}},
    software  = {https://github.com/aykutbulut/DisCO},
    year = {2017}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M. J. Saltzman, ALPS Version 1.5, COR@L Laboratory, Lehigh University, 2016. [Software] [DOI] [Bibtex]
    @Misc{ XuRalLadSal16-2,
    author  = {Xu, Y. and Ralphs, T.K. and Lad{\'a}nyi, L. and Saltzman,
    M.J.},
    doi = {10.5281/zenodo.245971},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{ALPS Version 1.5}},
    software  = {https://projects.coin-or.org/CHiPPS},
    year = {2016}
    }
  • A. Bulut and T. K. Ralphs, DietCOLA, COR@L Laboratory, Lehigh University, 2015. [Software] [Bibtex]
    @Misc{ BulRal15,
    author  = {Bulut, A. and Ralphs, T.K.},
    publisher  = {COR@L Laboratory, Lehigh University},
    title = {{DietCOLA}},
    software  = {https://github.com/aykutbulut/DietCOLA},
    year = {2015}
    }

Papers and Tech Reports

2017

  • T. K. Ralphs, “Duality, Branch and Bound, and Parametric Valid Inequalities,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Bibtex]
    @TechReport{ Ral17,
    author  = {Ralphs, T.K.},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{Duality, Branch and Bound, and Parametric Valid
    Inequalities}},
    year = {2017}
    }
  • A. Bulut and T. K. Ralphs, “DisCO: An Open Source Solver for Discrete Conic Optimization,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Software] [Bibtex]
    @TechReport{ BulRal17,
    software  = {https://github.com/aykutbulut/DisCO},
    author  = {Bulut, A and Ralphs, T K},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{DisCO: An Open Source Solver for Discrete Conic
    Optimization}},
    year = {2017}
    }
  • M. E. Pfetsch and T. K. Ralphs, “Towards More "Scientific" Computations in Mathematical Optimization,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Bibtex]
    @TechReport{ PfeRal17,
    author  = {Pfetsch, M.E. and Ralphs, T K},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{Towards More "Scientific" Computations in Mathematical
    Optimization}},
    year = {2017}
    }
  • A. Bulut and T. K. Ralphs, “Complexity for Mathematical Programs,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Bibtex]
    @TechReport{ BulRal17-1,
    author  = {Bulut, A and Ralphs, T K},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{Complexity for Mathematical Programs}},
    year = {2017}
    }
  • M. V. Galati and T. K. Ralphs, “DIP: A Framework for Decomposition in Integer Programming,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Software] [Bibtex]
    @TechReport{ GalRal17,
    software  = {https://projects.coin-or.org/Dip},
    author  = {Galati, M V and Ralphs, T K},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{DIP: A Framework for Decomposition in Integer
    Programming}},
    year = {2017}
    }
  • S. J. Maher, T. K. Ralphs, and Y. Shinano, “Assessing the Effectiveness of Branch-and-Bound Algorithms,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Bibtex]
    @TechReport{ MahRalShi17,
    author  = {Maher, S.J. and Ralphs, T.K. and Shinano, Y.},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{Assessing the Effectiveness of Branch-and-Bound
    Algorithms}},
    year = {2017}
    }
  • S. A. Tahernejad and T. K. Ralphs, “Valid Inequalities for Mixed Integer Bilevel Optimization,” Working Paper, COR@L Laboratory, Lehigh University 2017. [Software] [Bibtex]
    @TechReport{ TahRal17,
    software  = {https://github.com/tkralphs/MibS},
    author  = {Tahernejad, S.A. and Ralphs, T.K.},
    institution  = {Working Paper, COR@L Laboratory, Lehigh University},
    title = {{Valid Inequalities for Mixed Integer Bilevel
    Optimization}},
    year = {2017}
    }
  • M. Miltenberger, T. Ralphs, and D. Steffy, “Exploring the Numerics of Branch-and-Cut for Mixed Integer Linear Optimization,” in Operations Research Proceedings: 2017, 2017. [PDF] [Bibtex]
    @InProceedings{ MilRalSte17,
    author  = {Miltenberger, M and Ralphs, TK and Steffy, D},
    booktitle  = {Operations Research Proceedings: 2017},
    publisher  = {Springer Berlin / Heidelberg},
    title = {{Exploring the Numerics of Branch-and-Cut for Mixed
    Integer Linear Optimization}},
    url = {https://opus4.kobv.de/opus4-zib/files/6464/numerics{\_}in{\_}mip.pdf}
    ,
    year = {2017}
    }

2016

  • T. K. Ralphs, “Multistage Discrete Optimization,” in Bilevel Programming: Theory and Applications, S. Dempe, V. Kalashnikov, and B. Mordukhovich, Eds., Bantham Science Publishers, 2016. [Bibtex]
    @InCollection{ Ral16,
    author  = {Ralphs, T.K.},
    booktitle  = {Bilevel Programming: Theory and Applications},
    editor  = {Dempe, S and Kalashnikov, V and Mordukhovich, B},
    publisher  = {Bantham Science Publishers},
    title = {{Multistage Discrete Optimization}},
    year = {2016}
    }
  • P. Belotti, J. C. Góez, I. Pólik, T. K. Ralphs, and T. Terlaky, “A Complete Characterization of Disjunctive Conic Cuts for Mixed Integer Second Order Cone Optimization,” Discrete Optimization, vol. 24, 2016. [Software] [PDF] [DOI] [Bibtex]
    @Article{ BelGoePolRalTer16,
    abstract  = {{\textcopyright} 2016 Elsevier B.V. We study the convex
    hull of the intersection of a disjunctive set defined by
    parallel hyperplanes and the feasible set of a mixed
    integer second order cone optimization (MISOCO) problem. We
    extend our prior work on disjunctive conic cuts (DCCs),
    which has thus far been restricted to the case in which the
    intersection of the hyperplanes and the feasible set is
    bounded. Using a similar technique, we show that one can
    extend our previous results to the case in which that
    intersection is unbounded. We provide a complete
    characterization in closed form of the conic inequalities
    required to describe the convex hull when the hyperplanes
    defining the disjunction are parallel.},
    software  = {https://github.com/aykutbulut/CGL-CONIC},
    author  = {Belotti, P. and G{\'o}ez, J.C. and P{\'{o}}lik, I. and
    Ralphs, T.K. and Terlaky, T.},
    doi = {10.1016/j.disopt.2016.10.001},
    issn = {15725286},
    journal  = {Discrete Optimization},
    keywords  = {Disjunctive conic cuts,Disjunctive programming,Mixed
    integer optimization,Second order cone optimization},
    title = {{A Complete Characterization of Disjunctive Conic Cuts for
    Mixed Integer Second Order Cone Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ConicCuts14.pdf}
    ,
    volume  = {24},
    year = {2016}
    }
  • T. K. Ralphs, Y. Shinano, T. Berthold, and T. Koch, “Parallel Solvers for Mixed Integer Linear Programing,” COR@L Laboratory Report 16T-014-R3, Lehigh University 2016. To appear in Handbook of Parallel Constraint Reasoning. [PDF] [Bibtex]
    @TechReport{ RalShiBerKoc16,
    annote  = {To appear in Handbook of Parallel Constraint Reasoning},
    author  = {Ralphs, T K and Shinano, Y and Berthold, T and Koch, T},
    booktitle  = {Handbook of Parallel Constraint Reasoning},
    chapter  = {14},
    editor  = {Hamadi, Y and Sais, L},
    institution  = {COR@L Laboratory Report 16T-014-R3, Lehigh University},
    publisher  = {Springer Berlin / Heidelberg},
    title = {{Parallel Solvers for Mixed Integer Linear Programing}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ParallelMILPSurvey16.pdf}
    ,
    year = {2016}
    }
  • S. A. Tahernejad, S. T. DeNegre, and T. K. Ralphs, “A Branch-and-Cut Algorithm for Mixed Integer Bilevel Linear Optimization Problems and Its Implementation,” COR@L Technical Report 16T-015-R3 2016. [Software] [PDF] [Bibtex]
    @TechReport{ TahDeNRal16,
    software  = {https://github.com/tkralphs/MibS},
    author  = {Tahernejad, S.A. and DeNegre, S.T. and Ralphs, T.K.},
    institution  = {COR@L Technical Report 16T-015-R3},
    title = {{A Branch-and-Cut Algorithm for Mixed Integer Bilevel
    Linear Optimization Problems and Its Implementation}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MIBLP16.pdf},
    year = {2016}
    }
  • Y. Zhang, L. V. Snyder, T. K. Ralphs, and Z. Xue, “The Competitive Facility Location Problem Under Disruption Risks,” Transportation Research Part E: Logistics and Transportation Review, vol. 93, 2016. [PDF] [DOI] [Bibtex]
    @Article{ ZhaSnyRalXue16,
    abstract  = {{\textcopyright} 2016 Elsevier Ltd Two players
    sequentially locate a fixed number of facilities, competing
    to capture market share. Facilities face disruption risks,
    and each customer patronizes the nearest operational
    facility, regardless of who operates it. The problem
    therefore combines competitive location and location with
    disruptions. This combination has been absent from the
    literature. We model the problem as a Stackelberg game in
    which the leader locates facilities first, followed by the
    follower, and formulate the leader's decision problem as a
    bilevel optimization problem. A variable neighborhood
    decomposition search heuristic which includes variable
    fixing and cut generation is developed. Computational
    results suggest that high quality solutions can be found
    quickly. Interesting managerial insights are drawn.},
    author  = {Zhang, Y. and Snyder, L.V. and Ralphs, T.K. and Xue, Z.},
    doi = {10.1016/j.tre.2016.07.002},
    issn = {13665545},
    journal  = {Transportation Research Part E: Logistics and
    Transportation Review},
    keywords  = {Bilevel optimization,Competitive location,Facility
    disruptions,Local search,Variable neighborhood search},
    title = {{The Competitive Facility Location Problem Under
    Disruption Risks}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CFLPD16.pdf},
    volume  = {93},
    year = {2016}
    }

2015

  • A. Bulut and T. K. Ralphs, “On the Complexity of Inverse Mixed Integer Linear Optimization,” COR@L Laboratory Report 15T-001-R3, Lehigh University 2015. [Software] [PDF] [Bibtex]
    @TechReport{ BulRal15,
    software  = {https://github.com/tkralphs/CuPPy},
    author  = {Bulut, A and Ralphs, T.K.},
    institution  = {COR@L Laboratory Report 15T-001-R3, Lehigh University},
    title = {{On the Complexity of Inverse Mixed Integer Linear
    Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/InverseMILP15.pdf}
    ,
    year = {2015}
    }
  • P. Belotti, J. C. Góez, I. Pólik, T. K. Ralphs, and T. Terlaky, “A Conic Representation of the Convex Hull of Disjunctive Sets and Conic Cuts for Integer Second Order Cone Optimization,” in Numerical Analysis and Optimization, 2015. [PDF] [DOI] [Bibtex]
    @InProceedings{ BelGoePolRalTer15,
    abstract  = {{\textcopyright} Springer International Publishing
    Switzerland 2015. We study the convex hull of the
    intersection of a convex set E and a disjunctive set. This
    intersection is at the core of solution techniques for
    Mixed Integer Convex Optimization.We prove that if there
    exists a cone K (resp., a cylinder C) that has the same
    intersection with the boundary of the disjunction as E,
    then the convex hull is the intersection of E with K
    (resp., C). The existence of such a cone (resp., a
    cylinder) is difficult to prove for general conic
    optimization. We prove existence and unicity of a second
    order cone (resp., a cylinder), when E is the intersection
    of an affine space and a second order cone (resp., a
    cylinder). We also provide a method for finding that cone,
    and hence the convex hull, for the continuous relaxation of
    the feasible set of a Mixed Integer Second Order Cone
    Optimization (MISOCO) problem, assumed to be the
    intersection of an ellipsoid with a general linear
    disjunction. This cone provides a new conic cut for MISOCO
    that can be used in branch-and-cut algorithms for MISOCO
    problems.},
    author  = {Belotti, P. and G{\'o}ez, J.C. and P{\'{o}}lik, I. and
    Ralphs, T.K. and Terlaky, T.},
    booktitle  = {Numerical Analysis and Optimization},
    doi = {10.1007/978-3-319-17689-5_1},
    isbn = {9783319176888},
    issn = {21941017},
    keywords  = {Conic cuts,Mixed integer optimization,Second order cone
    Optimization},
    title = {{A Conic Representation of the Convex Hull of Disjunctive
    Sets and Conic Cuts for Integer Second Order Cone
    Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ConicCuts12.pdf}
    ,
    volume  = {134},
    year = {2015}
    }
  • T. K. Ralphs, “Data Science and Analytics,” Industrial and Systems Engineering Report 15T-009, Lehigh University 2015. [PDF] [Bibtex]
    @TechReport{ Ral15,
    author  = {Ralphs, T.K.},
    institution  = {Industrial and Systems Engineering Report 15T-009, Lehigh
    University},
    title = {{Data Science and Analytics}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/dataScience.pdf}
    ,
    year = {2015}
    }

2014

  • A. Lodi, T. K. Ralphs, and G. Woeginger, “Bilevel Programming and the Separation Problem,” Mathematical Programming, vol. 148, pp. 437-458, 2014. [PDF] [DOI] [Bibtex]
    @Article{ LodRalWoe14,
    author  = {Lodi, A and Ralphs, T K and Woeginger, G},
    doi = {10.1007/s10107-013-0700-x},
    journal  = {Mathematical Programming},
    pages = {437--458},
    title = {{Bilevel Programming and the Separation Problem}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BilevelSeparation12.pdf}
    ,
    volume  = {148},
    year = {2014}
    }
  • A. Hassanzadeh and T. K. Ralphs, “A Generalized Benders’ Algorithm for Two-Stage Stochastic Program with Mixed Integer Recourse,” COR@L Laboratory Report 14T-005, Lehigh University 2014. [Software] [PDF] [Bibtex]
    @TechReport{ HasRal14,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Hassanzadeh, A and Ralphs, T K},
    institution  = {COR@L Laboratory Report 14T-005, Lehigh University},
    title = {{A Generalized Benders' Algorithm for Two-Stage Stochastic
    Program with Mixed Integer Recourse}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/SMILPGenBenders14.pdf}
    ,
    year = {2014}
    }
  • A. Hassanzadeh and T. K. Ralphs, “On the Value Function of a Mixed Integer Linear Optimization Problem and an Algorithm for Its Construction,” COR@L Laboratory Report 14T-004, Lehigh University 2014. [Software] [PDF] [Bibtex]
    @TechReport{ HasRal14-1,
    software  = {https://github.com/tkralphs/ValueFunction},
    author  = {Hassanzadeh, A and Ralphs, T K},
    institution  = {COR@L Laboratory Report 14T-004, Lehigh University},
    title = {{On the Value Function of a Mixed Integer Linear
    Optimization Problem and an Algorithm for Its
    Construction}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MILPValueFunction14.pdf}
    ,
    year = {2014}
    }
  • T. K. Ralphs, M. Guzelsoy, and A. Mahajan, “SYMPHONY Version 5.6 User’s Manual,” COR@L Laboratory, Lehigh University 2014. [Software] [PDF] [Bibtex]
    @TechReport{ RalGuzMah14,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Guzelsoy, M and Mahajan, A},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.6 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/doc/SYMPHONY-5.6.9-Manual.pdf}
    ,
    year = {2014}
    }

2013

  • K. L. Hoffman and T. K. Ralphs, “Integer and Combinatorial Optimization,” 2013. [PDF] [DOI] [Bibtex]
    @TechReport{ HofRal13,
    author  = {Hoffman, K L and Ralphs, T K},
    booktitle  = {Encyclopedia of Operations Research and Management
    Science},
    doi = {10.1007/978-1-4419-1153-7_129},
    pages = {771--783},
    publisher  = {Springer},
    title = {{Integer and Combinatorial Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ICO-EORMS11.pdf}
    ,
    year = {2013}
    }
  • P. Belotti, J. C. Goez, I. Polik, T. K. Ralphs, and T. Terlaky, “On Families of Quadratic Surfaces Having Fixed Intersection with Two Hyperplanes,” Discrete Applied Mathematics, vol. 161, pp. 2778-2793, 2013. [PDF] [DOI] [Bibtex]
    @Article{ BelGoePolRalTer13,
    author  = {Belotti, P and Goez, J C and Polik, I and Ralphs, T K and
    Terlaky, T},
    doi = {10.1016/j.dam.2013.05.017},
    journal  = {Discrete Applied Mathematics},
    pages = {2778--2793},
    title = {{On Families of Quadratic Surfaces Having Fixed
    Intersection with Two Hyperplanes}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/Quadratic11.pdf}
    ,
    volume  = {161},
    year = {2013}
    }
  • T. K. Ralphs, M. Guzelsoy, and A. Mahajan, “SYMPHONY Version 5.5 User’s Manual,” COR@L Laboratory, Lehigh University 2013. [Software] [PDF] [Bibtex]
    @TechReport{ RalGuzMah13,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Guzelsoy, M and Mahajan, A},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.5 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/doc/SYMPHONY-5.5.0-Manual.pdf}
    ,
    year = {2013}
    }
  • J. Wang and T. Ralphs, “Computational Experience with Hypergraph-based Methods for Automatic Decomposition in Discrete Optimization,” in Proceedings of the Conference on Constraint Programming, Artificial Intelligence, and Operations Research, 2013, pp. 394-402. [Software] [PDF] [DOI] [Bibtex]
    @InProceedings{ WanRal13,
    abstract  = {Branch-and-price (BAP) algorithms based on Dantzig-Wolfe
    decomposition have shown great success in solving mixed
    integer linear optimization problems (MILPs) with specific
    identifiable structure. Only recently has there been
    investigation into the development of a "generic" version
    of BAP for unstructured MILPs. One of the most important
    elements required for such a generic BAP algorithm is an
    automatic method of decomposition. In this paper, we report
    on preliminary experiments using hypergraph partitioning as
    a means of performing such automatic decomposition.
    {\textcopyright} Springer-Verlag 2013.},
    software  = {https://projects.coin-or.org/Dip},
    author  = {Wang, J. and Ralphs, T.},
    booktitle  = {Proceedings of the Conference on Constraint Programming,
    Artificial Intelligence, and Operations Research},
    doi = {10.1007/978-3-642-38171-3_31},
    isbn = {9783642381706},
    issn = {03029743},
    pages = {394--402},
    title = {{Computational Experience with Hypergraph-based Methods
    for Automatic Decomposition in Discrete Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CPAIOR12.pdf}
    ,
    year = {2013}
    }

2012

  • M. V. Galati, T. K. Ralphs, and J. Wang, “Computational Experience with Generic Decomposition using the DIP Framework,” in Proceedings of RAMP 2012, 2012. [Software] [PDF] [Bibtex]
    @InProceedings{ GalRalWan12,
    software  = {https://projects.coin-or.org/Dip},
    author  = {Galati, M V and Ralphs, T K and Wang, J},
    booktitle  = {Proceedings of RAMP 2012},
    title = {{Computational Experience with Generic Decomposition using
    the DIP Framework}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/RAMP12.pdf},
    year = {2012}
    }
  • T. Koch, T. Ralphs, and Y. Shinano, “Could We Use a Million Cores to Solve an Integer Program?,” Mathematical Methods of Operations Research, vol. 76, pp. 67-93, 2012. [PDF] [DOI] [Bibtex]
    @Article{ KocRalShi12,
    author  = {Koch, T and Ralphs, TK and Shinano, Y},
    doi = {10.1007/s00186-012-0390-9},
    journal  = {Mathematical Methods of Operations Research},
    pages = {67--93},
    title = {{Could We Use a Million Cores to Solve an Integer
    Program?}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/Million11.pdf}
    ,
    volume  = {76},
    year = {2012}
    }

2011

  • M. Güzelsoy and T. K. Ralphs, “Warm-starting for Real-time Vehicle Routing,” COR@L Laboratory, Lehigh University 2011. [Software] [Bibtex]
    @TechReport{ GuzRal11,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {G{\"u}zelsoy, M and Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{Warm-starting for Real-time Vehicle Routing}},
    year = {2011}
    }
  • T. Koch, T. Achterburg, E. Andersen, O. Bastert, T. Berthold, R. E. Bixby, E. Danna, G. Gamrath, A. Gleixner, S. Heinz, A. Lodi, H. Mittelmann, T. K. Ralphs, D. Salvagnin, D. Steffy, and K. Wolter, “MIPLIB 2010,” Mathematical Programming Computation, vol. 3, pp. 103-163, 2011. [Software] [PDF] [DOI] [Bibtex]
    @Article{ KocAchAndBasBerBixDanGamGleHei.ea11,
    software  = {http://miplib.zib.de/download/scriptversions/},
    author  = {Koch, T and Achterburg, T and Andersen, E and Bastert, O
    and Berthold, T and Bixby, R E and Danna, E and Gamrath, G
    and Gleixner, A and Heinz, S and Lodi, A and Mittelmann, H
    and Ralphs, T K and Salvagnin, D and Steffy, D and Wolter,
    K},
    doi = {10.1007/s12532-011-0025-9},
    journal  = {Mathematical Programming Computation},
    pages = {103--163},
    title = {{MIPLIB 2010}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/miplib5.pdf},
    volume  = {3},
    year = {2011}
    }
  • A. Lodi, T. K. Ralphs, F. Rossi, and S. Smriglio, “Interdiction Branching,” COR@L Technical Report 11T-012-R2 2011. [Software] [PDF] [Bibtex]
    @TechReport{ LodRalRosSmr11,
    software  = {https://github.com/tkralphs/InterdictionBranch},
    author  = {Lodi, A and Ralphs, T K and Rossi, F and Smriglio, S},
    institution  = {COR@L Technical Report 11T-012-R2},
    title = {{Interdiction Branching}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BilevelBranching.pdf}
    ,
    year = {2011}
    }
  • T. K. Ralphs, M. Güzelsoy, and A. Mahajan, “SYMPHONY Version 5.3 User’s Manual,” COR@L Laboratory, Lehigh University 2011. [Software] [PDF] [Bibtex]
    @TechReport{ RalGuzMah11,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and G{\"u}zelsoy, M and Mahajan, A},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.3 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/doc/SYMPHONY-5.3.4-Manual.pdf}
    ,
    year = {2011}
    }
  • T. K. Ralphs, M. Güzelsoy, and A. Mahajan, “SYMPHONY Version 5.4 User’s Manual,” COR@L Laboratory, Lehigh University 2011. [Software] [PDF] [Bibtex]
    @TechReport{ RalGuzMah11-1,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and G{\"u}zelsoy, M and Mahajan, A},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.4 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/doc/SYMPHONY-5.4.0-Manual.pdf}
    ,
    year = {2011}
    }

2010

  • M. Güzelsoy and T. K. Ralphs, “Integer Programming Duality,” in Encyclopedia of Operations Research and Management Science, J. Cochran, Ed., Wiley, 2010. [PDF] [DOI] [Bibtex]
    @InCollection{ GuzRal10,
    author  = {G{\"u}zelsoy, M and Ralphs, T K},
    booktitle  = {Encyclopedia of Operations Research and Management
    Science},
    doi = {10.1002/9780470400531},
    editor  = {{J. Cochran}},
    publisher  = {Wiley},
    title = {{Integer Programming Duality}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/Duality-EOR10.pdf}
    ,
    year = {2010}
    }
  • T. K. Ralphs and M. V. Galati, “Decomposition Methods,” in Encyclopedia of Operations Research and Management Science, J. Cochran, Ed., Wiley, 2010. [PDF] [DOI] [Bibtex]
    @InCollection{ RalGal10,
    author  = {Ralphs, T K and Galati, M V},
    booktitle  = {Encyclopedia of Operations Research and Management
    Science},
    doi = {10.1002/9780470400531},
    editor  = {Cochran, J.},
    publisher  = {Wiley},
    title = {{Decomposition Methods}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/Decomp-EOR10.pdf}
    ,
    year = {2010}
    }
  • Z. Akca, R. T. Berger, and T. K. Ralphs, “Solution Methods for the Multi-trip Elementary Shortest Path Problem with Resource Constraints,” COR@L Laboratory, Lehigh University 2010. available by request. [PDF] [Bibtex]
    @TechReport{ AkcBerRal10,
    annote  = {available by request},
    author  = {Akca, Z and Berger, R T and Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{Solution Methods for the Multi-trip Elementary Shortest
    Path Problem with Resource Constraints}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MESPPRC10.pdf}
    ,
    year = {2010}
    }
  • A. Mahajan and T. K. Ralphs, “On the Complexity of Selecting Disjunctions in Integer Programming,” SIAM Journal on Optimization, vol. 20, iss. 5, pp. 2181-2198, 2010. [PDF] [DOI] [Bibtex]
    @Article{ MahRal10,
    author  = {Mahajan, A and Ralphs, T K},
    doi = {10.1137/080737587},
    journal  = {SIAM Journal on Optimization},
    number  = {5},
    pages = {2181--2198},
    title = {{On the Complexity of Selecting Disjunctions in Integer
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/Branching08.pdf}
    ,
    volume  = {20},
    year = {2010}
    }
  • T. K. Ralphs, A. Mahajan, and M. Güzelsoy, “SYMPHONY Version 5.2 User’s Manual,” COR@L Laboratory, Lehigh University 2010. [Software] [PDF] [Bibtex]
    @TechReport{ RalMahGuz10,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Mahajan, A and G{\"u}zelsoy, M},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.2 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/doc/SYMPHONY-5.2.3-Manual.pdf}
    ,
    year = {2010}
    }

2009

  • S. DeNegre and T. K. Ralphs, “A Branch-and-Cut Algorithm for Bilevel Integer Programming,” in Proceedings of the Eleventh INFORMS Computing Society Meeting, 2009, pp. 65-78. [Software] [PDF] [DOI] [Bibtex]
    @InProceedings{ DeNRal09,
    software  = {https://github.com/tkralphs/MibS},
    author  = {DeNegre, S and Ralphs, T K},
    booktitle  = {Proceedings of the Eleventh INFORMS Computing Society
    Meeting},
    doi = {10.1007/978-0-387-88843-9_4},
    pages = {65--78},
    title = {{A Branch-and-Cut Algorithm for Bilevel Integer
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BILEVEL08.pdf}
    ,
    year = {2009}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M J. Saltzman, “Computational Experience with a Software Framework for Parallel Integer Programming,” The INFORMS Journal on Computing, vol. 21, pp. 383-397, 2009. [Software] [PDF] [DOI] [Bibtex]
    @Article{ XuRalLadSal09,
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Xu, Y and Ralphs, T K and Lad{\'a}nyi, L and Saltzman, M
    J},
    doi = {10.1287/ijoc.1090.0347},
    journal  = {The INFORMS Journal on Computing},
    pages = {383--397},
    title = {{Computational Experience with a Software Framework for
    Parallel Integer Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CHiPPS-Rev.pdf}
    ,
    volume  = {21},
    year = {2009}
    }
  • Z. Akca, R. T. Berger, and T. K. Ralphs, “A Branch-and-Price Algorithm for Combined Location and Routing Problems Under Capacity Restrictions,” in Proceedings of the Eleventh INFORMS Computing Society Meeting, 2009, pp. 309-330. [PDF] [DOI] [Bibtex]
    @InProceedings{ AkcBerRal09,
    author  = {Akca, Z and Berger, R T and Ralphs, T K},
    booktitle  = {Proceedings of the Eleventh INFORMS Computing Society
    Meeting},
    doi = {10.1007/978-0-387-88843-9_16},
    pages = {309--330},
    title = {{A Branch-and-Price Algorithm for Combined Location and
    Routing Problems Under Capacity Restrictions}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/LRP08.pdf},
    year = {2009}
    }
  • A. Lodi and T. K. Ralphs, “Bilevel Programming and Maximally Violated Valid Inequalities,” in Proceedings of the Cologne Twente Workshop on Graphs and Combinatorial Optimization, 2009, pp. 125-134. [PDF] [Bibtex]
    @InProceedings{ LodRal09,
    author  = {Lodi, A and Ralphs, T K},
    booktitle  = {Proceedings of the Cologne Twente Workshop on Graphs and
    Combinatorial Optimization},
    pages = {125--134},
    title = {{Bilevel Programming and Maximally Violated Valid
    Inequalities}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CTW09.pdf},
    year = {2009}
    }
  • A. Mahajan and T. K. Ralphs, “Experiments with Branching using General Disjunctions,” in Proceedings of the Eleventh INFORMS Computing Society Meeting, 2009, pp. 101-118. [PDF] [DOI] [Bibtex]
    @InProceedings{ MahRal09,
    author  = {Mahajan, A and Ralphs, T K},
    booktitle  = {Proceedings of the Eleventh INFORMS Computing Society
    Meeting},
    doi = {10.1007/978-0-387-88843-9_6},
    pages = {101--118},
    title = {{Experiments with Branching using General Disjunctions}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CompBranching08.pdf}
    ,
    year = {2009}
    }

2008

  • M. Güzelsoy and T. K. Ralphs, “The Value Function of a Mixed-integer Linear Program with a Single Constraint,” COR@L Laboratory, Lehigh University 2008. [PDF] [Bibtex]
    @TechReport{ GuzRal08,
    author  = {G{\"u}zelsoy, M and Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{The Value Function of a Mixed-integer Linear Program with
    a Single Constraint}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ValueFunction.pdf}
    ,
    year = {2008}
    }
  • T. K. Ralphs, “SYMPHONY Version 5.1 User’s Manual,” COR@L Laboratory, Lehigh University 2008. [Software] [PDF] [Bibtex]
    @TechReport{ Ral08,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.1 User's Manual}},
    url = {http://www.coin-or.org/SYMPHONY/SYMPHONY-5.1.8-Manual.pdf}
    ,
    year = {2008}
    }
  • Z. Akca, R. T. Berger, and T. K. Ralphs, “Modeling and Solving Location, Routing, and Scheduling Problems,” COR@L Laboratory Report 08T-009, Lehigh University 2008. [PDF] [Bibtex]
    @TechReport{ AkcBerRal08,
    author  = {Akca, Z and Berger, R T and Ralphs, T K},
    institution  = {COR@L Laboratory Report 08T-009, Lehigh University},
    title = {{Modeling and Solving Location, Routing, and Scheduling
    Problems}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/LRSP08.pdf},
    year = {2008}
    }

2007

  • O. Osaltyn, B. Hunsaker, and T. K. Ralphs, “Visualizing Branch-and-Bound Algorithms,” COR@L Laboratory, Lehigh Univesity 2007. [Software] [PDF] [Bibtex]
    @TechReport{ OsaHunRal07,
    software  = {http://github.com/coin-or/GrUMPy},
    author  = {Osaltyn, O and Hunsaker, B and Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh Univesity},
    title = {{Visualizing Branch-and-Bound Algorithms}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BBVis.pdf},
    year = {2007}
    }
  • M. Güzelsoy and T. K. Ralphs, “Duality for Mixed-Integer Linear Programs,” International Journal of Operations Research, vol. 4, pp. 118-137, 2007. [PDF] [Bibtex]
    @Article{ GuzRal07,
    author  = {G{\"u}zelsoy, M and Ralphs, T K},
    journal  = {International Journal of Operations Research},
    pages = {118--137},
    title = {{Duality for Mixed-Integer Linear Programs}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MILPD06.pdf},
    volume  = {4},
    year = {2007}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M J. Saltzman, “Computational Experience with a Framework for Parallel Integer Programming,” COR@L Laboratory Report , Lehigh University 2007. [Software] [PDF] [Bibtex]
    @TechReport{ XuRalLadSal07,
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Xu, Y and Ralphs, T K and Lad{\'a}nyi, L and Saltzman, M
    J},
    institution  = {COR@L Laboratory Report , Lehigh University},
    title = {{Computational Experience with a Framework for Parallel
    Integer Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CHiPPS.pdf},
    year = {2007}
    }

2006

  • T. K. Ralphs, M. J. Saltzman, and M. M. Wiecek, “An Improved Algorithm for Biobjective Integer Programming,” Annals of Operations Research, vol. 147, pp. 43-70, 2006. [Software] [PDF] [DOI] [Bibtex]
    @Article{ RalSalWie06,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Saltzman, M J and Wiecek, M M},
    doi = {10.1007/s10479-006-0058-z},
    journal  = {Annals of Operations Research},
    pages = {43--70},
    title = {{An Improved Algorithm for Biobjective Integer
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BICRIT2.pdf},
    volume  = {147},
    year = {2006}
    }
  • T. K. Ralphs and M. V. Galati, “Decomposition and Dynamic Cut Generation in Integer Programming,” Mathematical Programming, vol. 106, pp. 261-285, 2006. [Software] [PDF] [DOI] [Bibtex]
    @Article{ RalGal06,
    software  = {https://projects.coin-or.org/},
    author  = {Ralphs, T K and Galati, M V},
    doi = {10.1007/s10107-005-0606-3},
    journal  = {Mathematical Programming},
    pages = {261--285},
    title = {{Decomposition and Dynamic Cut Generation in Integer
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/DECOMP.pdf},
    volume  = {106},
    year = {2006}
    }
  • T. K. Ralphs and M. Güzelsoy, “Duality and Warm Starting in Integer Programming,” in The Proceedings of the 2006 NSF Design, Service, and Manufacturing Grantees and Research Conference, 2006. [Software] [PDF] [Bibtex]
    @InProceedings{ RalGuz06,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and G{\"u}zelsoy, M},
    booktitle  = {The Proceedings of the 2006 NSF Design, Service, and
    Manufacturing Grantees and Research Conference},
    title = {{Duality and Warm Starting in Integer Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/DMII06.pdf},
    year = {2006}
    }
  • T. K. Ralphs, “Parallel Branch and Cut,” in Parallel Combinatorial Optimization, E. Talbi, Ed., New York: Wiley, 2006, pp. 53-101. [Software] [PDF] [Bibtex]
    @InCollection{ Ral06,
    address  = {New York},
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    booktitle  = {Parallel Combinatorial Optimization},
    editor  = {{E. Talbi}},
    pages = {53--101},
    publisher  = {Wiley},
    title = {{Parallel Branch and Cut}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/PBandC.pdf},
    year = {2006}
    }

2005

  • T. K. Ralphs and M. V. Galati, “Decomposition in Integer Programming,” in Integer Programming: Theory and Practice, J. Karlof, Ed., CRC Press, 2005, pp. 57-110. [PDF] [Bibtex]
    @InCollection{ RalGal05,
    author  = {Ralphs, T K and Galati, M V},
    booktitle  = {Integer Programming: Theory and Practice},
    editor  = {Karlof, J},
    pages = {57--110},
    publisher  = {CRC Press},
    title = {{Decomposition in Integer Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/DECOMP04.pdf}
    ,
    year = {2005}
    }
  • T. K. Ralphs and M. Giizelsoy, “The SYMPHONY Callable Library for Mixed Integer Programming,” in Proceedings of the Ninth INFORMS Computing Society Conference, 2005, pp. 61-76. [Software] [PDF] [DOI] [Bibtex]
    @InProceedings{ RalGii05,
    abstract  = {SYMPHONY is a customizable, open-source library for
    solving mixed-integer linear programs (MILP) by branch,
    cut, and price. With its large assortment of parameter
    settings, user callback functions, and compile-time
    options, SYMPHONY can be configured as a generic MILP
    solver or an engine for solving difficult MILPs by means of
    a fully customized algorithm. SYMPHONY can run on a variety
    of architectures, including single-processor,
    distributed-memory parallel, and shared-memory parallel
    architectures under MS Windows, Linux, and other Unix
    operating systems. The latest version is implemented as a
    callable library that can be accessed either through calls
    to the native C application program interface, or through a
    C++ interface class derived from the COIN-OR Open Solver
    Interface. Among its new features are the ability to solve
    bicriteria MILPs, the ability to stop and warm start MILP
    computations after modifying parameters or problem data,
    the ability to create persistent cut pools, and the ability
    to perform rudimentary sensitivity analysis on MILPs.
    {\textcopyright} 2005 Springer Science+Business Media,
    Inc.},
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T.K. and Giizelsoy, M.},
    booktitle  = {Proceedings of the Ninth INFORMS Computing Society
    Conference},
    doi = {10.1007/0-387-23529-9_5},
    issn = {1387666X},
    keywords  = {Branch and bound,Branch and cut,Integer
    programming,Sensitivity analysis,Software},
    pages = {61--76},
    title = {{The SYMPHONY Callable Library for Mixed Integer
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/SYMPHONY04.pdf}
    ,
    year = {2005}
    }
  • Y. Xu, T. K. Ralphs, L. Ladányi, and M. J. Saltzman, “ALPS: A Framework for Implementing Parallel Tree Search Algorithms,” in The Proceedings of the Ninth INFORMS Computing Society Conference, 2005, pp. 319-334. [Software] [PDF] [DOI] [Bibtex]
    @InProceedings{ XuRalLadSal05,
    abstract  = {ALPS is a framework for implementing and parallelizing
    tree search algorithms. It employs a number of features to
    improve scalability and is designed specifically to support
    the implementation of data intensive algorithms, in which
    large amounts of knowledge are generated and must be
    maintained and shared during the search. Implementing such
    algorithms in a scalable manner is challenging both because
    of storage requirements and because of communications
    overhead incurred in the sharing of data. In this abstract,
    we describe the design of ALPS and how the design addresses
    these challenges. We present two sample applications built
    with ALPS and preliminary computational results.
    {\textcopyright} 2005 Springer Science+Business Media,
    Inc.},
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Xu, Y. and Ralphs, T.K. and Lad{\'a}nyi, L. and Saltzman,
    M.J.},
    booktitle  = {The Proceedings of the Ninth INFORMS Computing Society
    Conference},
    doi = {10.1007/0-387-23529-9_21},
    issn = {1387666X},
    keywords  = {Branch and bound,Integer programming,Parallel
    algorithm,Software},
    pages = {319--334},
    title = {{ALPS: A Framework for Implementing Parallel Tree Search
    Algorithms}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ALPS04.pdf},
    volume  = {29},
    year = {2005}
    }
  • J. T. Linderoth and T. K. Ralphs, “Noncommercial Software for Mixed-Integer Linear Programming,” in Integer Programming: Theory and Practice, J. Karlof, Ed., CRC Press, 2005, pp. 253-303. [PDF] [Bibtex]
    @InCollection{ LinRal05,
    author  = {Linderoth, J T and Ralphs, T K},
    booktitle  = {Integer Programming: Theory and Practice},
    editor  = {Karlof, J},
    pages = {253--303},
    publisher  = {CRC Press},
    title = {{Noncommercial Software for Mixed-Integer Linear
    Programming}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MILP04.pdf},
    year = {2005}
    }

2004

  • T. K. Ralphs, M. J. Saltzman, and M. M. Wiecek, “An Improved Algorithm for Biobjective Integer Programming and Its Application to Network Routing Problems,” COR@L Laboratory Report 04T-004, Lehigh University 2004. [Software] [PDF] [Bibtex]
    @TechReport{ RalSalWie04,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Saltzman, M J and Wiecek, M M},
    institution  = {COR@L Laboratory Report 04T-004, Lehigh University},
    title = {{An Improved Algorithm for Biobjective Integer Programming
    and Its Application to Network Routing Problems}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BICRIT.pdf},
    year = {2004}
    }
  • T. K. Ralphs and M. Güzelsoy, “Duality, Warm Starting, and Sensitivity Analysis in Integer Programming,” COR@L Laboratory Report 04T-022, Lehigh University 2004. Available by request. [PDF] [Bibtex]
    @TechReport{ RalGuz04,
    annote  = {Available by request},
    author  = {Ralphs, T K and G{\"u}zelsoy, M},
    institution  = {COR@L Laboratory Report 04T-022, Lehigh University},
    title = {{Duality, Warm Starting, and Sensitivity Analysis in
    Integer Programming}},
    url = {http://ise.lehigh.edu/sites/ise.lehigh.edu/files/04t{\_}022.pdf}
    ,
    year = {2004}
    }
  • T. K. Ralphs, “SYMPHONY Version 5.0 User’s Manual,” COR@L Laboratory, Lehigh University, Technical Report , 2004. [Software] [Bibtex]
    @TechReport{ Ral04,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 5.0 User's Manual}},
    type = {Technical Report},
    year = {2004}
    }
  • R. Lougee-Heimer, M. J. Saltzman, and T. K. Ralphs, COIN of the OR Realm, , 2004. [PDF] [Bibtex]
    @Misc{ LouSalRal04,
    author  = {Lougee-Heimer, R and Saltzman, M J and Ralphs, T K},
    journal  = {OR/MS Today},
    month = {oct},
    title = {{COIN of the OR Realm}},
    url = {http://www.lionhrtpub.com/orms/orms-10-04/frcoin.html},
    year = {2004}
    }
  • T. K. Ralphs, L. Ladányi, and M. J. Saltzman, “A Library Hierarchy for Implementing Scalable Parallel Search Algorithms,” Journal of Supercomputing, vol. 28, pp. 215-234, 2004. [Software] [PDF] [DOI] [Bibtex]
    @Article{ RalLadSal04,
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Ralphs, T K and Lad{\'a}nyi, L and Saltzman, M J},
    doi = {10.1023/B:SUPE.0000020179.55383.ad},
    journal  = {Journal of Supercomputing},
    pages = {215--234},
    title = {{A Library Hierarchy for Implementing Scalable Parallel
    Search Algorithms}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/JSC02.pdf},
    volume  = {28},
    year = {2004}
    }

2003

  • T. K. Ralphs, L. Kopman, W. R. Pulleyblank, and L. E. Trotter Jr., “On the Capacitated Vehicle Routing Problem,” Mathematical Programming, vol. 94, pp. 343-359, 2003. [Software] [PDF] [DOI] [Bibtex]
    @Article{ RalKopPulTro-Jr03,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Kopman, L and Pulleyblank, W R and Trotter
    Jr., L E},
    doi = {10.1007/s10107-002-0323-0},
    journal  = {Mathematical Programming},
    pages = {343--359},
    title = {{On the Capacitated Vehicle Routing Problem}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/VRP.pdf},
    volume  = {94},
    year = {2003}
    }
  • T. K. Ralphs, “SYMPHONY Version 4.0 User’s Manual,” COR@L Laboratory, Lehigh University, Technical Report , 2003. [Software] [Bibtex]
    @TechReport{ Ral03,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{SYMPHONY Version 4.0 User's Manual}},
    type = {Technical Report},
    year = {2003}
    }
  • T. K. Ralphs, “Parallel Branch and Cut for Capacitated Vehicle Routing,” Parallel Computing, vol. 29, pp. 607-629, 2003. [Software] [PDF] [DOI] [Bibtex]
    @Article{ Ral03-1,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    doi = {10.1016/S0167-8191(03)00045-0},
    journal  = {Parallel Computing},
    pages = {607--629},
    title = {{Parallel Branch and Cut for Capacitated Vehicle
    Routing}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/PVRP.pdf},
    volume  = {29},
    year = {2003}
    }
  • T. K. Ralphs, L. Ladányi, and M. J. Saltzman, “Parallel Branch, Cut, and Price for Large-Scale Discrete Optimization,” Mathematical Programming, vol. 98, pp. 253-280, 2003. [Software] [PDF] [DOI] [Bibtex]
    @Article{ RalLadSal03,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Lad{\'a}nyi, L and Saltzman, M J},
    doi = {10.1007/s10107-003-0404-8},
    journal  = {Mathematical Programming},
    pages = {253--280},
    title = {{Parallel Branch, Cut, and Price for Large-Scale Discrete
    Optimization}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/PBCP.pdf},
    volume  = {98},
    year = {2003}
    }

2002

  • L. Ladányi, T. K. Ralphs, and M. J. Saltzman, “Implementing Scalable Parallel Search Algorithms for Data-Intensive Applications,” in Proceedings of the International Conference on Computational Science, 2002, pp. 592-602. [Software] [PDF] [DOI] [Bibtex]
    @InProceedings{ LadRalSal02,
    abstract  = {Scalability is a critical issue in the design of parallel
    software for large-scale search problems. Previous research
    has not addressed this issue for data-intensive
    applications. We describe the design of a library for
    parallel search that focuses on efficient data and search
    tree management for such applications in distributed
    computing environments. {\textcopyright} 2002
    Springer-Verlag Berlin Heidelberg.},
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Lad{\'a}nyi, L. and Ralphs, T.K. and Saltzman, M.J.},
    booktitle  = {Proceedings of the International Conference on
    Computational Science},
    doi = {10.1007/3-540-46043-8_60},
    isbn = {3540435913},
    issn = {03029743},
    pages = {592--602},
    title = {{Implementing Scalable Parallel Search Algorithms for
    Data-Intensive Applications}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ICCS02.pdf},
    year = {2002}
    }

2001

  • R. Lougee-Heimer, M. J. Saltzman, and T. K. Ralphs, The COIN-OR Initiative: Open-source Software Accelerates Operations Research Progress, , 2001. [PDF] [Bibtex]
    @Misc{ LouSalRal01,
    author  = {Lougee-Heimer, R and Saltzman, M J and Ralphs, T K},
    journal  = {OR/MS Today},
    title = {{The COIN-OR Initiative: Open-source Software Accelerates
    Operations Research Progress}},
    url = {http://lionhrtpub.com/orms/orms-10-01/forumfr.html},
    year = {2001}
    }
  • L. Ladányi, T. K. Ralphs, and L. E. Trotter Jr., “Branch, Cut, and Price: Sequential and Parallel,” in Computational Combinatorial Optimization, D. Naddef and M. Juenger, Eds., Berlin: Springer, 2001, pp. 223-260. [PDF] [DOI] [Bibtex]
    @InCollection{ LadRalTro-Jr01,
    address  = {Berlin},
    author  = {Lad{\'a}nyi, L and Ralphs, T K and Trotter Jr., L E},
    booktitle  = {Computational Combinatorial Optimization},
    doi = {10.1007/3-540-45586-8_6},
    editor  = {Naddef, D and Juenger, M},
    pages = {223--260},
    publisher  = {Springer},
    title = {{Branch, Cut, and Price: Sequential and Parallel}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/LNCS.pdf},
    year = {2001}
    }
  • T. K. Ralphs and L. Ladányi, “COIN/BCP User’s Manual,” COR@L Laboratory, Lehigh University 2001. [Software] [PDF] [Bibtex]
    @TechReport{ RalLad01,
    software  = {http://projects.coin-or.org/Bcp},
    author  = {Ralphs, T K and Lad{\'a}nyi, L},
    institution  = {COR@L Laboratory, Lehigh University},
    title = {{COIN/BCP User's Manual}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/BCP-Manual.pdf}
    ,
    year = {2001}
    }
  • T. K. Ralphs and J. C. Hartman, “Capacitated Network Routing (A Preliminary Progress Report),” COR@L Laboratory Report 01W-009, Lehigh University 2001. [Software] [PDF] [Bibtex]
    @TechReport{ RalHar01,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Hartman, J C},
    institution  = {COR@L Laboratory Report 01W-009, Lehigh University},
    title = {{Capacitated Network Routing (A Preliminary Progress
    Report)}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/CNRP.pdf},
    year = {2001}
    }
  • T. K. Ralphs, L. Ladányi, and M. J. Saltzman, “A Library Hierarchy for Implementing Scalable Parallel Search Algorithms,” Industrial and Systems Engineering, Lehigh University 2001. [Software] [PDF] [Bibtex]
    @TechReport{ RalLadSal01,
    software  = {https://projects.coin-or.org/CHiPPS},
    author  = {Ralphs, T K and Lad{\'a}nyi, L and Saltzman, M J},
    institution  = {Industrial and Systems Engineering, Lehigh University},
    title = {{A Library Hierarchy for Implementing Scalable Parallel
    Search Algorithms}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/ALPS.pdf},
    year = {2001}
    }

2000

  • T. K. Ralphs and L. Ladányi, “SYMPHONY: A Parallel Framework for Branch, Cut, and Price,” Rice University 2000. [Software] [Bibtex]
    @TechReport{ RalLad00,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K and Lad{\'a}nyi, L},
    institution  = {Rice University},
    title = {{SYMPHONY: A Parallel Framework for Branch, Cut, and
    Price}},
    year = {2000}
    }

1997

  • M. Esö, L. Ladányi, T. K. Ralphs, and L. E. Trotter Jr., “Fully Parallel Generic Branch-and-Cut Framework,” in Proceedings of the Eighth \SIAM\ Conference on Parallel Processing for Scientific Computing, 1997. [Software] [Bibtex]
    @InProceedings{ EsoLadRalTro-Jr97,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Es{\"o}, M and Lad{\'a}nyi, L and Ralphs, T K and Trotter
    Jr., L E},
    booktitle  = {Proceedings of the Eighth {\{}SIAM{\}} Conference on
    Parallel Processing for Scientific Computing},
    title = {{Fully Parallel Generic Branch-and-Cut Framework}},
    year = {1997}
    }

1995

  • T. K. Ralphs, “Parallel Branch and Cut for Vehicle Routing,” PhD Thesis, 1995. [Software] [Bibtex]
    @PhDThesis{ Ral95,
    software  = {https://projects.coin-or.org/SYMPHONY},
    author  = {Ralphs, T K},
    month = {may},
    school  = {Cornell University},
    title = {{Parallel Branch and Cut for Vehicle Routing}},
    year = {1995}
    }

1993

  • T. K. Ralphs, “On the Mixed Chinese Postman Problem,” Operations Research Letters, vol. 14, pp. 123-127, 1993. [PDF] [DOI] [Bibtex]
    @Article{ Ral93,
    author  = {Ralphs, T K},
    doi = {10.1016/0167-6377(93)90021-8},
    journal  = {Operations Research Letters},
    pages = {123--127},
    title = {{On the Mixed Chinese Postman Problem}},
    url = {http://coral.ie.lehigh.edu/~ted/files/papers/MPP.pdf},
    volume  = {14},
    year = {1993}
    }

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