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Last name: RODRÍGUEZ CHÍA
First name: Antonio Manuel
"El objetivo de la Teoría de la Localización consiste en determinar una o varias localizaciones para uno o más servicios con respecto a un conjunto de ubicaciones conocidas a priori, que usualmente denominamos puntos de demanda, optimizando alguna medida
En este trabajo se revisan tres modelos de problemas de localización continua: (1) un problema general de localización con respecto a regiones de demanda; (2) el problema de la mediana ordenada y (3) un problema de localización multiobjetivo. Con ellos se pretende dar una amplia muestra de los problemas que aparecen en el ámbito de la Teoría de...
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In this paper, we address the problem of locating mobile service units to cover random incidents. The model does not assume complete knowledge of the probability distribution of the location of the incident to be covered. Instead, only the mean value of that distribution is known. We propose the minimization of the maximum expected response...
We study finite dominating sets (FDS) for the ordered median problem. This kind of problems allows to deal simultaneously with a large number of models. We show that there is no valid polynomial size FDS for the general multifacility version of this problem even on path networks.
In this paper we address a planar p-facility location problem where, together with a metric induced by a gauge, there exists a series of rapid transit lines, which can be used as alternative transportation system to reduce the total transportation cost. The location problem is reduced to solving a finite number of (multi)-Weber problems, from...
We consider the single facility ordered median location problem with uncertainty in the parameters (weights) defining the objective function. We study two cases. In the first case the uncertain weights belong to a region with a finite number of extreme points, and in the second case they must also satisfy some order constraints and belong to...
This work focuses on support vector machine (SVM) with feature selection. A MILP formula- tion is proposed for the problem. The choice of suitable features to construct the separating hyperplanes has been modeled in this formulation by including a budget constraint that sets in advance a limit on the number of features to be used in the...
We propose a new optimization model to detect overlapping communities in networks. The model elaborates suggestions contained in Zhang et al. (2007), in which overlapping communities were identified through the use of a fuzzy membership function, calculated as the outcome of a mathematical programming problem. In our approach, we retain the...
Given a tree network T with n nodes, let PL be the subset of all discrete paths whose length is bounded above by a prespecified value L. We consider the location of a path-shaped facility P ∈ PL, where customers are represented by the nodes of the tree. We use a bi-criteria model to represent the total transportation cost of the customers to...
This paper deals with a cost sensitive extension of the standard Support Vector Machine (SVM) using an ordered weighted sum of the deviations of misclassified individuals with respect to their corresponding supporting hyperplanes. In contrast with previous heuristic approaches, an exact method that applies the ordered weighted average operator...
When dealing with location problems we are usually given a set of existing facilities and we are looking for the location of one or several new facilities. In the classical approaches weights are assigned to existing facilities expressing the importance of the new facilities for the existing ones. In this paper, we consider a pointwise de®ned...
We consider a discrete facility location problem with a new form of equity criterion. The model discussed in the paper analyzes the case where demand points only have strict preference order on the sites where the plants can be located. The goal is to find the location of the facilities minimizing the total envy felt by the entire set of demand...
This article deals with incorporating the mean absolute deviation objective function in several robust single facility location models on networks with dynamic evolution of node weights, which are modeled by means of linear functions of a parameter. Specifically, we have considered two robustness criteria applied to the mean absolute deviation...
The Single Allocation Ordered Median Hub Location problem is a recent hub model introduced in [36] J. Puerto, A.B. Ramos, and A.M. Rodríguez-Chía. Single-Allocation Ordered Median Hub Location Problems. Computers and Operations Research, 38:559-570, 2011.that provides a unifying analysis of a wide class of hub location models. In this paper,...
This paper presents new models for segmentation of 2D and 3D Scanning-Transmission Electron Micro- scope images based on the ordered median function. The main advantage of using this function is its good adaptability to the different types of images to be studied due to the wide range of weight vec- tors that can be cast. Classical segmentation...
This chapter analyzes multicriteria continuous, network, and discrete location problems. In the continuous framework, we provide a complete description of the set of weak Pareto, Pareto, and strict Pareto locations for a general Q-criteria location problem based on the characterization of three criteria problems. In the network case, the set of...