Numerical experiments with a modified regularization scheme for mathematical programs with complementarity constraints

On this paper we present a modified regularization scheme for Mathematical Programs with Complementarity Constraints. In the regularized formulations the complementarity condition is replaced by a constraint involving a positive parameter that can be decreased to zero. In our approach both the complementarity condition and the nonnegativity constraints are relaxed. An iterative algorithm is implemented in MATLAB language and a set of AMPL problems from MacMPEC database were tested.

A Java expression evaluator for nonlinear programming

Finding the optimal value for a problem is usual in many areas of knowledge where in many cases it is needed to solve Nonlinear Optimization Problems. For some of those problems it is not possible to determine the expression for its objective function and/or its constraints, they are the result of experimental procedures, might be non-smooth, among other reasons. To solve such problems it was implemented an API contained methods to solve both constrained and unconstrained problems. This API was developed to be used either locally on the computer where the application is being executed or remotely on a server. To obtain the maximum flexibility both from the programmers’ and users’ points of view, problems can be defined as a Java class (because this API was developed in Java) or as a simple text input that is sent to the API. For this last one to be possible it was also implemented on the API an expression evaluator. One of the drawbacks of this expression evaluator is that it is slower than the Java native code. In this paper it is presented a solution that combines both options: the problem can be expressed at run-time as a string of chars that are converted to Java code, compiled and loaded dynamically. To wide the target audience of the API, this new expression evaluator is also compatible with the AMPL format.

A filter algorithm: comparison with NLP solvers

The purpose of this work is to present an algorithm to solve nonlinear constrained optimization problems, using the filter method with the inexact restoration (IR) approach. In the IR approach two independent phases are performed in each iteration—the feasibility and the optimality phases. The first one directs the iterative process into the feasible region, i.e. finds one point with less constraints violation. The optimality phase starts from this point and its goal is to optimize the objective function into the satisfied constraints space. To evaluate the solution approximations in each iteration a scheme based on the filter method is used in both phases of the algorithm. This method replaces the merit functions that are based on penalty schemes, avoiding the related difficulties such as the penalty parameter estimation and the non-differentiability of some of them. The filter method is implemented in the context of the line search globalization technique. A set of more than two hundred AMPL test problems is solved. The algorithm developed is compared with LOQO and NPSOL software packages.

A filter inexact-restoration method for nonlinear programming

A new iterative algorithm based on the inexact-restoration (IR) approach combined with the filter strategy to solve nonlinear constrained optimization problems is presented. The high level algorithm is suggested by Gonzaga et al. (SIAM J. Optim. 14:646–669, 2003) but not yet implement—the internal algorithms are not proposed. The filter, a new concept introduced by Fletcher and Leyffer (Math. Program. Ser. A 91:239–269, 2002), replaces the merit function avoiding the penalty parameter estimation and the difficulties related to the nondifferentiability. In the IR approach two independent phases are performed in each iteration, the feasibility and the optimality phases. The line search filter is combined with the first one phase to generate a “more feasible” point, and then it is used in the optimality phase to reach an “optimal” point. Numerical experiences with a collection of AMPL problems and a performance comparison with IPOPT are provided.

Clima.

2006

Macroeducação: parcerias para uma sociedade sustentável.

O livro Proposta Metodológica de Macroeducação é uma coletânea publicada pela Empresa Brasileira de Pesquisa Agropecuária, Embrapa. É o volume 2 da série ?Educação Ambiental para o desenvolvimento Sustentável?, que reúne sete volumes, todos eles obras coletâneas. Levam o mérito de serem realizados de forma participativa, desde a escolha dos títulos, dos temas às revisões. Quanto à abrangência do livro resenhado, desde 2004 foram impressos 8.074 exemplares. A leitura se faz obrigatoriamente em meio impresso, uma vez que não está disponível para download, até o momento. O seu preço é acessível (R$ 18,00, em média) nas livrarias da Embrapa, mas exemplares com valores menores são encontrados nas principais livrarias on-line, chegando a custar R$ 5,40.

Non emergency patients transport - a mixed integer linear programming

This work presents a model and a heuristic to solve the non-emergency patients transport (NEPT) service issues given the new rules recently established in Portugal. The model follows the same principle of the Team Orienteering Problem by selecting the patients to be included in the routes attending the maximum reduction in costs when compared with individual transportation. This model establishes the best sets of patients to be transported together. The model was implemented in AMPL and a compact formulation was solved using NEOS Server. A heuristic procedure based on iteratively solving problems with one vehicle was presented, and this heuristic provides good results in terms of accuracy and computation time.

The non-emergency patient transport modelled as a team orienteering problem

This work presents an improved model to solve the non-emergency patients transport (NEPT) service issues given the new rules recently established in Portugal. The model follows the same principle of the Team Orienteering Problem by selecting the patients to be included in the routes attending the maximum reduction in costs when compared with individual transportation. This model establishes the best sets of patients to be transported together. The model was implemented in AMPL and a compact formulation was solved using NEOS Server. A heuristic procedure based on iteratively solving Orienteering Problems is presented, and this heuristic provides good results in terms of accuracy and computation time. Euclidean instances as well as asymmetric real data gathered from Google maps were used, and the model has a promising performance mainly with asymmetric cost matrices.

Otimização com restrições de complementaridade: algoritmos e aplicações

Tese de Doutoramento em Engenharia Industrial e de Sistemas (PDEIS)

Relatório sobre “Surgical cases packages”

Problema apresentado pelo Hospital de Braga no 109th European Study Group with Industry 10 a 15 de maio de 2015. Departamento de Produção e Sistemas Escola de Engenharia da Universidade do Minho Guimarães Portugal 24 de julho de 2015

Concilium Pisanum, 1409.

F. 1 Réponse des cardinaux à Rodolphe, secrétaire de Charles Malatesta (Mansi, XXVII, 239-245). F. 5 et 12v CAROLUS DE MALATESTIS, Lettres aux cardinaux (ibid., 226-238 et Martène et Durand, Ampl. coll., VII, 1143-1162). F. 29v Informatio gestorum cum patribus Pisis congregatis pro universali concilio (Mansi, XXVII, 245-313). F. 85 CAROLUS DE MALATESTIS, Responsio ad relata sibi per episcopum Cerviensem ex parte Alexandri (Martène et Durand, op. cit., 1136-1140). F. 88 ALEXANDER V, Replicatio ad « ambasitam » factam sibi per episcopum Cerviensem ex parte Caroli de Malatestis (ibid., 1140-1141). F. 88v et 97v Ambassades envoyées par Charles Malatesta aux cardinaux de Bologne, à l'occasion de la mort d'Alexandre V, 1410 (ibid., 1141-1142) et à Jean XXIII (ibid., 1171-1173). F. 108v Informatio ad regem Romanorum pro tranquillitate ecclesiae (ibid., 1187-1193). F. 124v Table analytique.

Amplification of the DFR1 gene in Saccaromyces cerevisiae

A new system was employed to study amplification of t,he DHF'R gene DFB,1 ) in Sa<,:;charoillYCB§. .Q~~Yi...S!i<;1~. . This system consists of a series of yeast strains containing a casset,te which encodes t he yeast, D..ERl gene ttghtly linked tjO a f usion of the yeast 1EU2. regulat,ory region wi tJ1 the LAQZ str ctural gene from E. cO.1-1 (,) . M. Clement , unpubl i,::;hed) . Th's casset;t e was shown t.o be integrat,ed int o a unj que chromosomal l ocati on in each strain . Yeast cells were se l ected for MTX-resistance and overproduction of ~ galac t osi d se ( B-gal ). Since the inserted DF'Rl and ~ACZ genes are independently regulated, it was thought that cel l s with this phenotype probably contain e d ampl if ications of the cassette. A lar ge variat ion in the f requn y o f MTX-resistance was found between the di ff e r ent str ains. These freqlen c ~ es r anged from about 2 x 10 - 7 fo r a population of cells containing the cassette integrated at, the BI J2.l gene in t,he middle of the long arm of chromosome V, to about 5 x 10-4 for a strain with the cassette i nserted in the r DNA cluster Abo It 85% of the MTX- res i stcmt iso l ates examined showed enhanced B·-gal act i v ity rel a t ive t o the parental strain . For the ma jorit y of strains, the mean B- gal activity in drug-r sistant clones was about 3 times that o f the parent following a single se l ect i on step . I n con t r ast, primary MTX-resistant derivat~ves of cells with the cassette inserted 3 at the rDNA cluster showed inc r eases in B- gal activity ranging from 9 - 14 f old r elative to the parent. Analysis of the latte r s train by Southe rn hybr idization indicated that the cassette was inde e d amplified several fold in MTX-re sistant derivatives. A sing l e strain, in which the cassette was inserted at the !lEA;], loc u.s , was used to examine in more detai 1 , the parameters affecting DFRl gene amplificat~ion in yeast . The mean B- gal activity in drug-resistant derivatives of this strain could be increased from 3 to 6 or 7 fold relative to the parent, by stepwise sel ection using increasing MTX concentrations. B-gal overproduction was found to be un stable in all primary and highly -resistant isolates examined. There was no indication, h owever, of a decrease i n growth r a t e in MTX-res i s tant cells which overproduced B - gal.

El papel del entrenamiento autoguiado en la relaci??n entre el conflicto de tarea y la innovaci??n en equipos virtuales

Resumen tomado de la publicaci??n

Cognitive appraisals, emotional reactions, and their associations with three forms of peer-victimization

Resumen tomado de la publicaci??n

Una aproximaci?? a l'index de preus al consum. 'Una aproximaci??n al ??ndice de precios al consumo'

Cr??dito variable de ampliaci??n para trabajar interdisciplinariamente las ??reas de Matem??ticas y Ciencias Sociales en los ??ltimos cursos de la ESO. Pretende que el alumno ampl??e el concepto de proporci??n para poder introducir las progresiones geom??tricas y la funci??n exponencial y consiste en la utilizaci??n de las variaciones porcentuales en el contexto del aumento del coste de la vida. Integra el siguiente tipo de material did??ctico: 1) Introducci??n al concepto de variaci??n perceptual. 2) Problemas de aplicaci??n para elaborar conceptos, trabajos fuera de clase, etc. 3) Trabajo de consolidaci??n: elaboraci??n de un IPC.