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313
MIP models for MIP heuristics
, 2006
"... Modern MIP solvers exploit a rich arsenal of tools to attack hard problems, some of which include the solution of LP models to control the branching strategy (strong branching), the cut generation (lift-and-project), the heuristics (reduced costs), etc. As a matter of fact, it is well understood by ..."
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” (MIPping) some crucial decisions to be taken within a MIP algorithm. In particular, we will address the possible benefits deriving from the use of an black-box MIP solver to produce heuristic primal solutions for a generic MIP. We will first review the so-called local branching [1] and RINS [2] paradigms
Matrix-Dependent Prolongations and Restrictions in a Black-Box Multigrid Solver
, 1990
"... Multigrid methods are studied for the solution of linear systems resulting from the 9-point discretization of a general linear second-order elliptic partial differential equation in two dimensions. The rate of convergence of standard multigrid methods often deteriorates when the coefficients in the ..."
Abstract
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Cited by 78 (8 self)
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in the differential equation are discontinuous, or when dominating first-order terms are present. These difficulties may be overcome by choosing the prolongation and restriction operators in a special way. A novel way to do this is proposed. As a result, a black-box solver (written in standard FORTRAN 77) has been
Numerical engineering: design of PDE black-box solvers
"... The design of PDE black-box solvers (for nonlinear systems of elliptic and parabolic PDEs) needs many compro-mises between efficiency and robustness which we call ‘Numerical Engineering’. The requirements for a black-box solver are formulated and the way how to meet them is presented, guided by many ..."
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The design of PDE black-box solvers (for nonlinear systems of elliptic and parabolic PDEs) needs many compro-mises between efficiency and robustness which we call ‘Numerical Engineering’. The requirements for a black-box solver are formulated and the way how to meet them is presented, guided
Black-Box Preconditioning For Mixed Formulation . . .
, 2002
"... Mixed finite element approximation of self-adjoint elliptic PDEs leads to symmetric indefinite linear systems of equations. Preconditioning strategies commonly focus on reduced symmetric positive definite systems and require nested iteration. This deficiency is avoided if preconditioned minres is ap ..."
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is applied to the full indefinite system. We outline such a preconditioning strategy, the key building block for which is a fast solver for a scalar diffusion operator based on black-box algebraic multigrid. Numerical results are presented for the Stokes equations arising in incompressible ow modelling and a
Black-box Hartree-Fock solver by tensor numerical methods
- Preprint 90/2013, MPI
, 2013
"... The Hartree-Fock eigenvalue problem governed by the 3D integro-differential oper-ator is the basic model in ab initio electronic structure calculations. Several years ago the idea to solve the Hartree-Fock equation by fully 3D grid based numerical approach seemed to be a fantasy, and the tensor-stru ..."
Abstract
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Cited by 8 (2 self)
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-structured methods did not exist. In fact, these methods evolved during the work on this challenging problem. In this paper, our recent results on the topic are outlined and the black-box Hartee-Fock solver by tensor numer-ical methods is presented. The approach is based on the rank-structured calculation
Activity-based search for black-box constraint programming solvers
- In Integration of AI and OR Techniques in Contraint Programming for Combinatorial Optimzation Problems - 9th International Conference, CPAIOR 2012
"... Abstract. Robust search procedures are a central component in the de-sign of black-box constraint-programming solvers. This paper proposes activity-based search which uses the activity of variables during propaga-tion to guide the search. Activity-based search was compared experimen-tally to impact- ..."
Abstract
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Cited by 5 (0 self)
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Abstract. Robust search procedures are a central component in the de-sign of black-box constraint-programming solvers. This paper proposes activity-based search which uses the activity of variables during propaga-tion to guide the search. Activity-based search was compared experimen-tally to impact
Activity-Based Search for Black-Box Contraint-Programming Solvers
, 2011
"... Robust search procedures are a central component in the design of black-box constraint-programming solvers. This paper proposes activity-based search, the idea of using the activity of variables during propagation to guide the search. Activity-based search was compared experimentally to impact-base ..."
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Robust search procedures are a central component in the design of black-box constraint-programming solvers. This paper proposes activity-based search, the idea of using the activity of variables during propagation to guide the search. Activity-based search was compared experimentally to impact
Exploiting the power of MIP solvers in Maxsat
- In Proc. SAT, volume 7962 of LNCS
, 2013
"... Abstract. maxsat is an optimization version of satisfiability. Since many practical problems involve optimization, there are a wide range of potential applications for effective maxsat solvers. In this paper we present an extensive empirical evaluation of a number of maxsat solvers. In addition to t ..."
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Cited by 7 (1 self)
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to traditional maxsat solvers, we also evaluate the use of a state-of-the-art Mixed Integer Program (mip) solver, cplex, for solving maxsat. mip solvers are the most popular technology for solving opti-mization problems and are also theoretically more powerful than sat solvers. In fact, we show that cplex
An adaptive radial basis algorithm (ARBF) for expensive black-box global optimization’.
- Journal of Global Optimization, DOI 10.1007/s10898-007-9256-8, ISSN 0925-5001 (Print)
, 2007
"... Abstract Response surface methods based on kriging and radial basis function (RBF) interpolation have been successfully applied to solve expensive, i.e. computationally costly, global black-box nonconvex optimization problems. In this paper we describe extensions of these methods to handle linear, ..."
Abstract
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Cited by 9 (0 self)
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Abstract Response surface methods based on kriging and radial basis function (RBF) interpolation have been successfully applied to solve expensive, i.e. computationally costly, global black-box nonconvex optimization problems. In this paper we describe extensions of these methods to handle linear
A Black-Box Solver For The Solution Of General Nonlinear Functional Equations By Mixed FEM
- FINITE ELEMENT METHODS, FIFTY YEARS OF THE COURANT ELEMENT
, 1994
"... A black-box solver for the solution of nonlinear functional equations is a compromise of flexibilty, efficiency and stability of the algorithms. We will present a general form of functional equation, a general error indicator and the efficient interaction of the error indicator and the Newton-Raphso ..."
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Cited by 2 (2 self)
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A black-box solver for the solution of nonlinear functional equations is a compromise of flexibilty, efficiency and stability of the algorithms. We will present a general form of functional equation, a general error indicator and the efficient interaction of the error indicator and the Newton
Results 1 - 10
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313