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  • A flow formulation for the optimum communication spanning tree

     Fernandez Areizaga, Elena; Luna Mota, Carlos; Hildenbrandt, Achim; Reinelt, Gerard; Wiesberg, Stefan
    International Network Optimization Conference
    Presentation's date: 2013-05-20
    Presentation of work at congresses

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    In this paper we address the Optimum Communication Spanning Tree Problem. We present a formulation that uses three index variables and we propose several families of inequalities, which can be used to reinforce the formulation. Preliminary computational experiments are very promising.

  • The maximum dispersion problem

     Fernandez Areizaga, Elena; Kalcsics, Jörg; Nickel, Stefan
    Omega: the international journal of management science
    Date of publication: 2013-08
    Journal article

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  • GRASP and path relinking for the clustered prize-collecting arc routing problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena; Franquesa, Carles
    Journal of heuristics
    Date of publication: 2013-04
    Journal article

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  • A flow formulation for the Optimum Communication Spanning Tree

     Fernandez Areizaga, Elena; Luna Mota, Carlos; Hildenbrandt, Achim; Reinelt, Gerard; Wiesberg, Stefan
    Electronic notes in discrete mathematics
    Date of publication: 2013
    Journal article

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    In this paper we address the Optimum Communication Spanning Tree Problem. We present a formulation that uses three index variables and we propose several families of inequalities, which can be used to reinforce the formulation. Preliminary computational experiments are very promising.

  • Discrete optimization with ordering

     Fernandez Areizaga, Elena; Puerto, Justo; Rodríguez-Chia, A
    Annals of operations research
    Date of publication: 2013
    Journal article

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  • The capacitated minimum spanning tree problem  Open access

     Ruiz Y ruiz, Héctor Efraín
    Defense's date: 2013-07-15
    Universitat Politècnica de Catalunya
    Theses

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    In this thesis we focus on the Capacitated Minimum Spanning Tree (CMST), an extension of the minimum spanning tree (MST) which considers a central or root vertex which receives and sends commodities (information, goods, etc) to a group of terminals. Such commodities flow through links which have capacities that limit the total flow they can accommodate. These capacity constraints over the links result of interest because in many applications the capacity limits are inherent. We find the applications of the CMST in the same areas as the applications of the MST; telecommunications network design, facility location planning, and vehicle routing. The CMST arises in telecommunications networks design when the presence of a central server is compulsory and the flow of information is limited by the capacity of either the server or the connection lines. Its study also results specially interesting in the context of the vehicle routing problem, due to the utility that spanning trees can have in constructive methods. By the simple fact of adding capacity constraints to the MST problem we move from a polynomially solvable problem to a non-polynomial one. In the first chapter we describe and define the problem, introduce some notation, and present a review of the existing literature. In such review we include formulations and exact methods as well as the most relevant heuristic approaches. In the second chapter two basic formulations and the most used valid inequalities are presented. In the third chapter we present two new formulations for the CMST which are based on the identification of subroots (vertices directly connected to the root). One way of characterizing CMST solutions is by identifying the subroots and the vertices assigned to them. Both formulations use binary decision variables y to identify the subroots. Additional decision variables x are used to represent the elements (arcs) of the tree. In the second formulation the set of x variables is extended to indicate the depth of the arcs in the tree. For each formulation we present families of valid inequalities and address the separation problem in each case. Also a solution algorithm is proposed. In the fourth chapter we present a biased random-key genetic algorithm (BRKGA) for the CMST. BRKGA is a population-based metaheuristic, that has been used for combinatorial optimization. Decoders, solution representation and exploring strategies are presented and discussed. A final algorithm to obtain upper bounds for the CMST is proposed. Numerical results for the BRKGA and two cutting plane algorithms based on the new formulations are presented in the fifth chapter . The above mentioned results are discussed and analyzed in this same chapter. The conclusion of this thesis are presented in the last chapter, in which we include the opportunity areas suitable for future research.

    En esta tesis nos enfocamos en el problema del Árbol de Expansión Capacitado de Coste Mínimo (CMST, por sus siglas en inglés), que es una extensión del problema del árbol de expansión de coste mínimo (MST, por sus siglas en inglés). El CMST considera un vértice raíz que funciona como servidor central y que envía y recibe bienes (información, objetos, etc) a un conjunto de vértices llamados terminales. Los bienes solo pueden fluir entre el servidor y las terminales a través de enlaces cuya capacidad es limitada. Dichas restricciones sobre los enlaces dan relevancia al problema, ya que existen muchas aplicaciones en que las restricciones de capacidad son de vital importancia. Dentro de las áreas de aplicación del CMST más importantes se encuentran las relacionadas con el diseño de redes de telecomunicación, el diseño de rutas de vehículos y problemas de localización. Dentro del diseño de redes de telecomunicación, el CMST está presente cuando se considera un servidor central, cuya capacidad de transmisión y envío está limitada por las características de los puertos del servidor o de las líneas de transmisión. Dentro del diseño de rutas de vehículos el CMST resulta relevante debido a la influencia que pueden tener los árboles en el proceso de construcción de soluciones. Por el simple de añadir las restricciones de capacidad, el problema pasa de resolverse de manera exacta en tiempo polinomial usando un algoritmo voraz, a un problema que es muy difícil de resolver de manera exacta. En el primer capítulo se describe y define el problema, se introduce notación y se presenta una revisión bibliográfica de la literatura existente. En dicha revisión bibliográfica se incluyen formulaciones, métodos exactos y los métodos heurísticos utilizados más importantes. En el siguiente capítulo se muestran dos formulaciones binarias existentes, así como las desigualdades válidas más usadas para resolver el CMST. Para cada una de las formulaciones propuestas, se describe un algoritmo de planos de corte. Dos nuevas formulaciones para el CMST se presentan en el tercer capítulo. Dichas formulaciones estás basadas en la identificación de un tipo de vértices especiales llamados subraíces. Los subraíces son aquellos vértices que se encuentran directamente conectados al raíz. Un forma de caracterizar las soluciones del CMST es a través de identificar los nodos subraíces y los nodos dependientes a ellos. Ambas formulaciones utilizan variables para identificar los subraices y variables adicionales para identificar los arcos que forman parte del árbol. Adicionalmente, las variables en la segunda formulación ayudan a identificar la profundidad con respecto al raíz a la que se encuentran dichos arcos. Para cada formulación se presentan desigualdades válidas y se plantean procedimientos para resolver el problema de su separación. En el cuarto capítulo se presenta un algoritmo genético llamado BRKGA para resolver el CMST. El BRKGA está basado en el uso de poblaciones generadas por secuencias de números aleatorios, que posteriormente evolucionan. Diferentes decodificadores, un método de búsqueda local, espacios de búsqueda y estrategias de exploración son presentados y analizados. El capítulo termina presentando un algoritmo final que permite la obtención de cotas superiores para el CMST. Los resultados computacionales para el BRKGA y los dos algoritmos de planos de corte basados en las formulaciones propuestas se muestran en el quinto capítulo. Dichos resultados son analizados y discutidos en dicho capítulo. La tesis termina presentando las conclusiones derivadas del desarrollo del trabajo de investigación, así como las áreas de oportunidad sobre las que es posible realizar futuras investigaciones.

  • Modelos y Métodos de Programación Matemática y sus aplicaciones (OPTIMOS3)

     Fernandez Areizaga, Elena
    Participation in a competitive project

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  • Minimizing the maximum travel time in a combined model of facility location and network design

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena; Reineltc, Gerhard
    Omega: the international journal of management science
    Date of publication: 2012-12
    Journal article

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    This paper presents a combined Facility Location/Network Design Problem which simultaneously considers the location of facilities and the design of its underlying network so as to minimize the maximum customer-facility travel time. The model generalizes the classical p-center problem and has various applications in regional planning, distribution, telecommunications, emergency systems, and other areas. Two mixed integer programming formulations are presented and compared. Several valid inequalities are derived for the most promising of these formulations to strengthen its LP relaxation bound and to reduce the enumeration tree. Numerical results of a series of computational experiments for instances with up to 100 nodes and 500 candidate links are reported.

  • Combination of vehicle routing models and dynamic traffic simulation for city logistics applications  Open access

     Grzybowska, Hanna
    Defense's date: 2012-06-08
    Department of Statistics and Operations Research, Universitat Politècnica de Catalunya
    Theses

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    The urban network is a highly dynamic system. Thus, a modern and efficient fleet management in urban areas should account for dynamics of traffic conditions, variability in travel times, changes in demand and fleet availability. All these factors significantly affect the distribution of goods and the provision of services. As a consequence, the freight operations optimizing approaches should be based on the time-dependent travel time estimates rather than on the average static values commonly employed as input data. Proficient dynamic fleet management decisions need to take into consideration all the factors conditioning the addressed problem. Hence, the customers’ requests and service conditions (demands, time windows, etc.), operational conditions of the employed fleet (vehicles’ availability, status, positions, current occupancy of the carriage space, etc.) and traffic conditions need to be reckoned with. This information can be provided in the real-time fashion and at an affordable price by the ICT applications and tools such as: ATIS, GPS, GPRS or other. Instead of relying exclusively on the experience of a dispatcher, it is effective to base the freight management decisions on information provided by a professional Decision Support System facilitating the consideration of all the factors conditioning the addressed issue. The objective of the present thesis is to propose, implement and computationally test, on the basis of a simulation, the architecture of a Decision Support System for real-time freight management able of accounting for all the dynamic factors mentioned above. Its design is based on integration of a selected pickup and delivery vehicle routing model and dynamic traffic simulation models, whose purpose is to carefully emulate the evolving traffic conditions. The optimal dynamic routing and scheduling of a vehicle fleet is obtained due to dynamic modifications of the current routing and scheduling plan on the basis of the recently revealed information conditioning the addressed problem. The obtained results of computational experiments show that the performance of freight fleet strongly depends on the traffic information used to create the routing and scheduling plan. Due to the special character of transport operations performed in metropolitan areas it is possible that not all the scheduled customers would be served, although a feasible initial solution is created on the basis of the historical travel times’ data. Hence, there is a need to implement real-time rerouting strategies allowing modifications of the original routes in order to feasibly fulfil the routing tasks. In addition, the tighter the constraints specifying the customers’ time windows and the higher the number of dynamically appearing requests, the higher the cost of the performance and the level of utilization of the freight fleet.

    La red urbana es un sistema altamente dinámico. Por lo tanto, la gestión moderna y eficiente de la flota en las zonas urbanas debe tener en cuenta la dinámica de las condiciones del tráfico, la variabilidad en los tiempos de viaje y los cambios en la disponibilidad de la demanda y de la flota, ya que afectan de manera significativa en la distribución de bienes y la prestación de servicios. Como consecuencia, los enfoques para optimizar las operaciones de carga deben basarse en las estimaciones de los tiempos de viaje dependientes del tiempo y no en los valores medios estáticos comúnmente empleados como datos de entrada. Las decisiones competentes de gestión dinámica de las flotas necesitan tener en cuenta todos los factores que condicionan el problema abordado. Por lo tanto, hay que considerar las características de las peticiones y las condiciones de servicio de los clientes (demanda, ventanas de tiempo, etc.), las condiciones operacionales de la flota empleada (disponibilidad de los vehículos, estatus, ubicación, ocupación actual del espacio de transporte, etc.) y las condiciones de tráfico. Esta información puede ser proporcionada en tiempo real a un precio asequible por las aplicaciones de las TIC y herramientas tales como: ATIS, GPS, GPRS u otros. En lugar de confiar exclusivamente en la experiencia de un distribuidor, también sería correcto basar las decisiones de gestión de transporte de mercancías en la información proporcionada por un sistema profesional de apoyo a la toma de decisiones que facilita la consideración de todos los factores que condicionan el problema abordado. El objetivo de esta tesis es proponer, implementar y validar computacionalmente en base a la simulación, la arquitectura de un Sistema de Apoyo a la Toma de Decisiones para la gestión de transporte de mercancías en tiempo real capaz de considerar todos los factores dinámicos previamente mencionados. Su diseño se basa en la integración de un modelo seleccionado de rutas de vehículos con recogida y entrega y modelos de simulación de tráfico dinámicos cuyo propósito es emular detalladamente las condiciones de tráfico que cambian con el paso del tiempo. Las rutas y los horarios dinámicos óptimos para una flota de vehículos que transporta mercancías se obtienen de las modificaciones dinámicas de un plan actual de rutas y horarios en base a la nueva información recibida que condiciona el problema abordado. Los resultados obtenidos de los experimentos computacionales demuestran que el rendimiento de la flota de transporte de mercancías depende en gran medida de la información de tráfico utilizada para crear el plan de rutas y los horarios. Debido al carácter especial de las operaciones de transporte realizadas en las áreas metropolitanas, a pesar de una solución inicial factible que se crea sobre la base de los datos históricos de los tiempos de viaje, es posible que no todos los clientes sean servidos. Por lo tanto, hay una necesidad de implementar estrategias de cambios de rutas en tiempo real, que permiten modificar las rutas originales con el fin de cumplir las tareas de enrutamiento viables. Además, más estrictas son las limitaciones que especifican las ventanas del tiempo de los clientes y más alto es el número de solicitudes de servicio que aparecen de forma dinámica, mayor será el coste final de las prestaciones del servicio y el nivel de utilización de la flota de transporte de mercancías.

  • General network design : a unified view of combined location and network design problems

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena
    European journal of operational research
    Date of publication: 2012-06-16
    Journal article

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    This paper presents a unified framework for the general network design problem which encompasses several classical problems involving combined location and network design decisions. In some of these problems the service demand relates users and facilities, whereas in other cases the service demand relates pairs of users between them, and facilities are used to consolidate and re-route flows between users. Problems of this type arise in the design of transportation and telecommunication systems and include well-known problems such as location-network design problems, hub location problems, extensive facility location problems, tree-star location problems and cycle-star location problems, among others. Relevant modeling aspects, alternative formulations and possible algorithmic strategies are presented and analyzed.

  • Multiperiod location-routing with decoupled time scales

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Nickel, Stefan
    European journal of operational research
    Date of publication: 2012-03-01
    Journal article

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    This paper focuses on a multiperiod discrete facility location problem where transportation costs are considered together with location costs to design the operating facility pattern along a time horizon. The problem captures the difference in the scope of the location and routing decisions by considering different scales within the time horizon. Thus, solutions to this problem reflect the stability of locational decisions along time. The high complexity of this problem makes it impossible to be solved in practice with commercial software. For this reason, an approximation based on replacing vehicle routes by spanning trees is proposed, and its capability for providing good quality solutions is assessed in a series of computational experiments.

  • The formulation of the hub arc location problem

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena
    Euro Working Group on Locational Analysis Meeting
    Presentation's date: 2011-10
    Presentation of work at congresses

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  • A computational comparison of several models for the exact solution of the capacity and distance constrained plant location problem

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Laporte, Gilbert
    Computers & operations research
    Date of publication: 2011
    Journal article

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  • Branch and price for large-scale capacitated hub location problems with single assignment

     Contreras Aguilar, Ivan; Díaz García, Juan A.; Fernandez Areizaga, Elena
    Informs journal on computing
    Date of publication: 2011
    Journal article

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  • The facility location problem with Bernoulli demands

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Saldanha da Gama, Francisco
    Omega: the international journal of management science
    Date of publication: 2011-06
    Journal article

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  • The Windy clustered prize-collecting arc-routing problem

     Corberan, Angel; Fernandez Areizaga, Elena; Franquesa Niubo, Carles; Sanchis, Jose Maria
    Transportation science
    Date of publication: 2011-08
    Journal article

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    This paper introduces the windy clustered prize-collecting arc-routing problem. It is an arc-routing problem where each demand edge is associated with a profit that is collected once if the edge is serviced, independent of the number of times the edge is traversed. It is further required that if a demand edge is serviced, then all the demand edges of its component are also serviced. A mathematical programming formulation is given and some polyhedral results including several facet-defining and valid inequalities are presented. The separation problem for the different families of inequalities is studied. Numerical results from computational experiments are analyzed.

  • The generalized arc routing problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena; Franquesa, Carles
    Conference of the International Federation of Operation Research Societies
    Presentation's date: 2010-07-10
    Presentation of work at congresses

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  • Estudio del itinerario academico de las mujeres matematicas en España

     Casanellas Rius, Marta; Fernandez Areizaga, Elena
    Participation in a competitive project

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  • MODELOS Y METODOS DE PROGRAMACION MATEMATICA Y SUS APLICACIONES (OPTIMOS2)

     Franquesa Niubo, Carles; Contreras Aguilar, Ivan; Araoz Durand, Julian Arturo; Albareda Sambola, Maria; Luna Mota, Carlos; Ruiz Ruiz, Hector Efrain; Fernandez Areizaga, Elena
    Participation in a competitive project

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  • Lagrangean duals and exact solution to the capacitated p-center problem

     Albareda Sambola, Maria; Díaz, Juan A.; Fernandez Areizaga, Elena
    European journal of operational research
    Date of publication: 2010-02
    Journal article

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  • The Tree of Hubs Location Problem

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena; Marín, Alfredo
    European journal of operational research
    Date of publication: 2010-04
    Journal article

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  • Lagrangean bounds for the optimum communication spanning tree problem

     Contreras, I.; Fernandez Areizaga, Elena; Marín, Alfredo
    TOP
    Date of publication: 2010
    Journal article

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    This paper considers the Optimum Communication Spanning Tree Problem. An integer programming formulation that yields tight LP bounds is proposed. Given that the computational effort required to obtain the LP bounds considerably increases with the size of the instances when using commercial solvers, we propose a Lagrangean relaxation that exploits the structure of the formulation. Since feasible solutions to the Lagrangean function are spanning trees, upper bounds are also obtained. These bounds are later improved with a simple local search. Computational experiments have been run on several benchmark instances from the literature. The results confirm the interest of the proposal since tight lower and upper bounds are obtained, for instances up to 100 nodes, in competitive computational times.

  • Solving the Prize-collecting Rural Postman Problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena; Meza, Oscar
    European journal of operational research
    Date of publication: 2009-08
    Journal article

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  • The Clustered Prize-Collecting Arc Routing Problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena; Franquesa Niubo, Carles
    Transportation science
    Date of publication: 2009-08
    Journal article

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  • The multi-period incremental service facility location problem

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Hinojosa, Yolanda; Puerto, Justo
    Computers & operations research
    Date of publication: 2009
    Journal article

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    In this paper we introduce the multi-period incremental service facility location problem where the goal is to set a number of new facilities over a finite time horizon so as to cover dynamically the demand of a given set of customers. We prove that the coefficient matrix of the allocation subproblem that results when fixing the set of facilities to open is totally unimodular. This allows to solve efficiently the Lagrangean problem that relaxes constraints requiring customers to be assigned to open facilities. We propose a solution approach that provides both lower and upper bounds bt combining subgradient optimization to solve a Lagrangean dual with an ad hoc heuristic that uses information from the Lagrangean subproblem to generate feasible solutions. Numerical results obtained in the computational experiments show that the obtained solutions are very good. In general, we get very small percent gaps between upper and lower bounds with little computation effort.

  • The capacity and distance constrained plant location problem

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Gilbert, Laporte
    Computers & operations research
    Date of publication: 2009-02
    Journal article

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  • A reactive GRASP for a commercial territory design problem with multiple balancing requirements

     Rios-Mercado, Rz; Fernandez Areizaga, Elena
    Computers & operations research
    Date of publication: 2009-03
    Journal article

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  • Tight bounds from a path based formulation for the tree of hub location problem

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena; Marin, A
    Computers & operations research
    Date of publication: 2009-12
    Journal article

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  • GEVA: geometric variability-based approaches for identifying patterns in data

     Irigoien, I.; Arenas, Concepción; Fernandez Areizaga, Elena; Mestres, Francisco
    Computational statistics
    Date of publication: 2009-10-15
    Journal article

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    This paper, arising from population studies, develops clustering algorithms for identifying patterns in data. Based on the concept of geometric variability, we have developed one polythetic-divisive and three agglomerative algorithms. The effectiveness of these procedures is shown by relating them to classical clustering algorithms. They are very general since they do not impose constraints on the type of data, so they are applicable to general (economics, ecological, genetics…) studies. Our major contributions include a rigorous formulation for novel clustering algorithms, and the discovery of new relationship between geometric variability and clustering. Finally, these novel procedures give a theoretical frame with an intuitive interpretation to some classical clustering methods to be applied with any type of data, including mixed data. These approaches are illustrated with real data on Drosophila chromosomal inversions.

  • The Single Period Coverage Facility Location Problem: Lagrangean heuristic and column generation approaches

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Hinojosa, Yolanda; Puerto Albandoz, Justo
    TOP
    Date of publication: 2009
    Journal article

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  • A computational comparison of several formulations for the multi-period incremental service facility location problem

     Albareda Sambola, Maria; Alonso Ayuso, Antonio; Escudero Bueno, Laureano; Fernandez Areizaga, Elena; Hinojosa, Yolanda; Pizarro Romero, Celeste
    TOP
    Date of publication: 2009
    Journal article

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  • Lagrangean relaxation for the capacitated hub location problem with single assignment

     Contreras Aguilar, Ivan; Díaz, Juan A.; Fernandez Areizaga, Elena
    OR spect
    Date of publication: 2009-06
    Journal article

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  • Network Hub Location: models, algorithms, and related problems.

     Contreras Aguilar, Ivan
    Defense's date: 2009-02-09
    Department of Statistics and Operations Research, Universitat Politècnica de Catalunya
    Theses

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  • An LP based algorithm for the Privatized Rural Postman Problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena
    European journal of operational research
    Date of publication: 2008-12
    Journal article

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  • A Lagrangean Relaxation Approach for the Capacitated Single Allocation Hub Location Problem

     Contreras, I; Díaz, J A; Fernandez Areizaga, Elena
    OR spect
    Date of publication: 2008-06
    Journal article

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  • Access to the full text
    Solving an Urban Waste Collection Problem Using Ants Heuristics  Open access

     Bautista Valhondo, Joaquin; Fernandez Areizaga, Elena; Pereira Gude, Jorge
    Computers & operations research
    Date of publication: 2008-09
    Journal article

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    This paper describes the methodology that we have applied for the solution of an urban waste collection problem in the municipality of Sant Boi de Llobregat, within the metropolitan area of Barcelona (Spain). The basic nature of the considered problem is that of a capacitated arc routing problem, although it has several specific characteristics, mainly derived from trafic regulations. We present the model that we have built for the problem, which results after an appropriate transformation of the problem into a node routing one. We also present the ant colonies heuristics that we have used to obtain the solutions to the problem. These combine constructive methods, based on nearest neighbor and on nearest insertion, with a local search that explores various neighborhoods. The application of the proposed methods gives results that improve considerably the ones that were previously used in the municipality.

  • The Facility Location Problem with Bernoulli Demands

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Saldanha da Gama, Francisco
    Optimization online
    Date of publication: 2008-08
    Journal article

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  • The Clustered Prize-collecting Arc Routing Problem

     Franquesa Niubo, Carles
    Defense's date: 2008-11-27
    Department of Statistics and Operations Research, Universitat Politècnica de Catalunya
    Theses

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  • Models and algorithms for the optimum communication spanning tree problem

     Contreras Aguilar, Ivan; Fernandez Areizaga, Elena; Marín, A.
    International Workshop on Operational Research
    Presentation's date: 2008-07-06
    Presentation of work at congresses

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  • Solving the Capacitated Hub Location Problems with Single Assignment with Branch-and-Price

     Fernandez Areizaga, Elena
    International Symposium on Locational Decisions
    Presentation's date: 2008-06-26
    Presentation of work at congresses

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  • Red Temática Localización y Problemas Afines

     Albareda Sambola, Maria; Fernandez Areizaga, Elena
    Participation in a competitive project

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  • The exact solution to the Clustered Price-collecting Arc Routing problem

     Fernandez Areizaga, Elena
    International Federation of Operational Research Societies Conference
    Presentation's date: 2008-07-13
    Presentation of work at congresses

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  • The Tree of Hubs Location Problem

     Fernandez Areizaga, Elena
    International Symposium on Locational Decisions
    Presentation's date: 2008-06-26
    Presentation of work at congresses

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  • The Clustered Price-collecting Arc Routing Problem

     Araoz Durand, Julian Arturo; Fernandez Areizaga, Elena; Franquesa, Carles
    Graph Optimization Meeting GOM 2008
    Presentation's date: 2008-08-01
    Presentation of work at congresses

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  • A reactive GRASP for a commercial territory design problem with multiple balancing requirements

     Rios-Mercado, Roger Z; Fernandez Areizaga, Elena
    Computers & operations research
    Date of publication: 2007-11
    Journal article

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  • Heuristic and lower bound for a stochastic location-routing problem

     Albareda Sambola, Maria; Fernandez Areizaga, Elena; Laporte, G
    European journal of operational research
    Date of publication: 2007-06
    Journal article

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  • Glum: a cluster program for analyzing microarrary data

     Iriogen, I; Fernandez Areizaga, Elena; Vives, S; Arenas, C
    Russian journal of genetics
    Date of publication: 2007-12
    Journal article

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  • ANÁLISIS Y APLICACIONES DE DECISIONES SOBRE LOCALIZACIÓN DE SERVICIOS Y PROBLEMAS RELACIONADOS

     Albareda Sambola, Maria; Fernandez Areizaga, Elena
    Participation in a competitive project

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  • Red Temática en Optimización bajo incertidumbre. MTM2006-26619-E

     Fernandez Areizaga, Elena; Albareda Sambola, Maria; Corchero García, Cristina
    Participation in a competitive project

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  • Red temática: Análisis y Aplicaciones de Decisiones sobre Localización de Servicios y Problemas Relacionados. (MTM2006-27490-E).

     Fernandez Areizaga, Elena; Araoz Durand, Julian Arturo
    Participation in a competitive project

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