Reports de recerca
Recent Submissions
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On solving large-scale multistage stochastic problems with a new specialized interior-point approach
(2021-12)
Research report
Open AccessA novel approach based on a specialized interior-point method (IPM) is presented for solving large-scale stochastic multistage continuous optimization problems, which represent the uncertainty in strategic multistage and ... -
New interior-point approach for one- and two-class linear support vector machines using multiple variable splitting
(2021-12)
Research report
Open AccessMultiple variable splitting is a general technique for decomposing problems by using copies of variables and additional linking constraints that equate their values. The resulting large optimization problem can be solved ... -
An algorithm for the microaggregation problem using column generation
(2020-06)
Research report
Open AccessThe field of Statistical Disclosure Control aims at reducing the risk of re-identification of an individualwhen disseminating data, and it is one of the main concerns of national statistical agencies. OperationsResearch ... -
A new interior-point approach for large two-stage stochastic problems
(2020-04)
Research report
Open AccessTwo-stage stochastic models give rise to very large optimization problems. Several approaches havebeen devised for efficiently solving them, including interior-point methods (IPMs). However, usingIPMs, the linking columns ... -
Using interior point solvers for optimizing progressive lens models with spherical coordinates
(2019-05)
Research report
Open AccessDesigning progressive lenses is a complex problem that has beenpreviously solved by formulating an optimization model based on Cartesiancoordinates. In this work a new progressive lens model using spherical co-ordinates ... -
A specialized interior-point algorithm for huge minimum convex cost flows in bipartite networks
(2019-01-28)
Research report
Open AccessThe computation of the Newton direction is the most time consuming step of interior-point methods. This direction was efficiently computed by a combination of Cholesky factorizations and conjugate gradients in a specialized ... -
A specialized interior-point algorithm for huge minimum convex cost flows in bipartite networks
(2018-11)
Research report
Open Access -
A linear optimization based method for data privacy in statistical tabular data
(2017-05-23)
Research report
Open AccessNational Statistical Agencies routinely disseminate large amounts of data. Prior to dissemination these data have to be protected to avoid releasing confidential information. Controlled tabular adjustment (CTA) is one of ... -
Stabilized Benders methods for large-scale combinatorial optimization, with appllication to data privacy
(2017-10-24)
Research report
Open AccessThe Cell Suppression Problem (CSP) is a challenging Mixed-Integer Linear Problem arising in statistical tabular data protection. Medium sized instances of CSP involve thousands of binary variables and million of continuous ... -
Bases numèriques de les rutines del paquet "POPNOLC", "AGTU", "AFAU", "AFSU, i "AQCH" d'actualització de factoritzacions de Cholesky, per addició o sostracció de matrius de rang U
(1985)
Research report
Open AccessEfectua una deducció dels algorismes coneguts i d'actualització de factoritzacions de Cholesky de matrius simàtriques definides positives, per addició o sostracció de matrius de rang u. A més se'n fa una anàlisi numèrica ... -
On geometrical properties of preconditioners in IPMs for classes of block-angular problems
(2016-02)
Research report
Open AccessOne of the most efficient interior-point methods for some classes of block-angular structured problems solves the normal equations by a combination of Cholesky factorizations and preconditioned conjugate gradient ... -
A cutting-plane approach for large-scale capacitated multi-period facility location using a specialized interior-point method
(2015-06)
Research report
Open AccessWe propose a cutting-plane approach (namely, Benders decomposition) for a class of capacitated multi-period facility location problems. The novelty of this approach lies on the use of a specialized interior-point method ...