Alejandro Escudero-Santana | Universidad de Sevilla (original) (raw)

Papers by Alejandro Escudero-Santana

Research in Transportation Economics, 2021

Intermodal freight transport consists of using different modes of transport without changing the ... more Intermodal freight transport consists of using different modes of transport without changing the load unit. This results in a significant reduction in the time that goods spend at intermodal terminals, where transshipment takes place. Drayage refers to the transport of freight on trucks among intermodal terminals, depots, customers and suppliers. In spite of the fact that drayage only represents between 5 and 10 percent of total distance, it may amount up to more than 30 percent of the total costs. The aim of this work is to study drayage operations. First, an extensive literature review is undertaken. Since the intermodal transport chain can become more efficient by means of a proper organisation of the drayage movements, the optimization of the daily drayage problem has been identified as one of the main ways of reducing the drayage cost and improving intermodal operations. On this problem, the lack of a common benchmark has hindered reaching further conclusions from all the research carried out. Therefore, this paper proposes a common framework and presents a generalized formulation of the problem, which allows modeling most drayage policies, with the limitation of only considering one-container problems. Results show that flexible tasks in the repositioning of empty containers as well as soft time windows can reduce the operating costs and facilitate the management of drayage companies. This work may help consider adequate policies regarding drayage operations in intermodal terminals.

Aula Abierta, 2021

La transmisión de conceptos mediante juegos combina una aplicación práctica de la teoría junto co... more La transmisión de conceptos mediante juegos combina una aplicación práctica de la teoría junto con un incremento potencial del inte- rés y la motivación de los alumnos. Este objetivo en el caso de la transmisión de conceptos de la gestión de proyectos ágil, mediante la metodología Scrum, se consigue mediante un juego aplicado a la logística, que se propone en esta comunicación, en la que se explica la dinámica del juego, y cómo se reflejan todos los conceptos de esta metodología ágil.

Aula Abierta, 2019

En la última década la universidad española ha sufrido una gran transformación debido al proceso ... more En la última década la universidad española ha sufrido una gran transformación debido al proceso de Bolonia, el cual buscaba acercar la Universidad a las necesidades sociales. Aun así, sigue existiendo un considerable gap entre los conocimientos adquiridos en las enseñanzas universitarias y las competencias reclamadas en el mercado laboral. Los grados en ingeniería, no están carentes de esta problemática, siendo muchos los estudiantes que muestran dificultades en el desarrollo de ciertas competencias apreciadas en los entornos profesionales. Este trabajo recoge la experiencia que vienen desarrollando un grupo de profesores del área de Organización de Empresas para fomentar la relación entre la Universidad y la empresa. Enmarcado dentro del Plan de Innovación Docente de la Universidad de Sevilla, la propuesta se fundamenta en: simulaciones empresariales y un ciclo de conferencias. Los resultados obtenidos pueden considerarse muy positivos.

Dirección y Organización, 2019

El objetivo de este estudio es analizar la aplicabilidad del confort adaptativo a edificios escol... more El objetivo de este estudio es analizar la aplicabilidad del confort adaptativo a edificios escolares en el sur de España. Se busca comprender mejor la percepción del confort térmico, encontrar las posibilidades de ahorro energético y analizar las características de los estudios en los escolares y sus aptitudes conductuales relacionadas. Además, se propone la metodología más idónea y los tamaños de las muestras de los estudios hasta ahora desarrollados, para definir el desarrollo de un estudio de confort adaptativo para edificios escolares en Andalucía, estos estudios están dirigidos a conseguir alcanzar el máximo confort posible junto al ahorro energético.

Dirección y Organización, 2019

La enorme aceptación que la filosofía Lean Manufacturing ha tenido en la industria ha llevado a q... more La enorme aceptación que la filosofía Lean Manufacturing ha tenido en la industria ha llevado a que esta esté incluida en muchos planes de estudios de ingeniería industrial, normalmente en la intensificación de producción. El aprendizaje de la fabricación ajustada requiere un conocimiento previo de muchos conceptos de los sistemas de producción, además de una puesta en práctica de este conocimiento. Debido a que las prácticas en entornos reales no siempre son factibles en un entorno académico, se diseñó un método de enseñanza integrada donde la gamificación representaba un rol fundamental. Los resultados obtenidos, tanto de satisfacción de los alumnos como de logro en el alcance de competencias, han sido enormemente satisfactorios. Palabras clave Gamificación, aprendizaje activo, sistemas de producción, cooperación con industria, lean manufacturing.

Transport, 2018

The high volume of traffic originates two well-known problems in many cities: congestion and poll... more The high volume of traffic originates two well-known problems in many cities: congestion and pollution. In recent years, a social phenomenon is emerging cooperation. This work is aimed at evaluating the circumstances under which transport cooperation is possible between different stakeholders operating in the same geographical area. To this end, a double survey process was conducted in a marketplace situated in the Seville City (Spain) centre. The first survey was designed to know the characteristics of the retailers and their preferences with respect to cooperation and regulations. A rela-tional analysis between retailer features and their willingness to cooperate was carried out. After analysing the motivations for non-cooperation, a mixed proposal was designed and surveyed. Although the research was limited to a marketplace, the relevant data gathered from this double survey process highlights some implications: (a) the importance of personal relations in retailer cooperation; (b) a high volume of freight and the use of vans as on-street warehouses appear as significant motivations for non-cooperation; (c) forcing changes in the statu quo encourages cooperation.

Complexity, Feb 8, 2018

The application of the principles of sustainability to the implementation of urban freight polici... more The application of the principles of sustainability to the implementation of urban freight policies requires the estimation of all the costs and externalities involved. We focus here on the case of access time windows, which ban the access of freight vehicles to central urban areas in many European cities. Even though this measure seeks to reduce congestion and emissions in the most crowded periods of the day, it also imposes additional costs for carriers and results in higher emissions and energy consumption. We present here a mathematical model for the Vehicle Routing Problem with Access Time Windows, a variant of the VRP suitable for planning delivery routes in a city subject to this type of accessibility restriction. We use the model to find exact solutions to small problem instances based on a case study and then compare the performance over larger instances of a modified savings algorithm, a genetic algorithm, and a tabu search procedure, with the results showing no clear prevalence of any of them, but confirming the significance of those additional costs and externalities.

Journal of Navigation, 2018

The planning of vessel navigation along a tidal river is a complex task that can affect the effic... more The planning of vessel navigation along a tidal river is a complex task that can affect the efficiency of inland ports and intermodal chains. The availability of water may represent a significant restriction to port accessibility, having an impact on waiting times, cost and even safety. This paper presents a heuristic procedure to schedule vessels on a tidal waterway, which seeks to optimise navigation according to a multi-criteria objective function combining the number of vessels serviced, the total waiting time, the waterway occupation time and the number of crossing operations, where the term “crossing” implies inbound and outbound vessels passing each other. The procedure requires a previous step of estimation of real-time water depth, which identifies the critical points or navigation bottlenecks along the waterway, and contemplates the possibility of vessels having to anchor in the middle of their journey and wait for next tide rise. We validate the procedure through its application to a set of real and test problems and show that its results are reliable in terms of performance and solution quality.

Journal of Transport Geography, Feb 2017

Despite the ubiquity of loading zones in most commercially dense streets of medium and large citi... more Despite the ubiquity of loading zones in most commercially dense streets of medium and large cities, there exists no generally acknowledged procedure to establish their number, location and management system. We propose a methodology divided in two steps, where the first one estimates the required number of loading zones on a given street and the second one locates them taking into account the delivery characteristics of the retail establishments they will be serving. The application of the methodology is tested in four streets in the Spanish city of Seville, following a retailer survey to collect all the relevant data. The results provided by the application in terms of number and location of loading zones are simulated together with other scenarios with different numbers of loading zones, and the outcomes are compared with the existing situation. The new methodology results in an improvement in the level of service provided with a similar – or smaller – number of loading zones, but most importantly causes a significant reduction in the distances between loading zone parking spaces and final destinations.

Revista Transporte y Territorio, 2017

Resumen El reparto urbano de mercancías debe ser contemplado en relación con los tres ejes de la ... more Resumen El reparto urbano de mercancías debe ser contemplado en relación con los tres ejes de la sostenibilidad: el económico, el social y el medioambiental. Dentro de los parámetros del desarrollo urbano sostenible, es importante conseguir una logística urbana sostenible y eficiente, lo cual es extremadamente complejo debido a la gran variedad de repartos de mercancía existentes en la ciudad y a los numerosos grupos de actores involucrados en el problema, lo cual genera con frecuencia numerosas áreas de conflicto. En este artículo se describe toda esa complejidad y se detallan las principales respuestas que pueden darse en el ámbito urbano, tanto a nivel empresarial como desde la administración local, teniendo en cuenta el riesgo de que en ocasiones el resultado de las medidas impuestas para conseguir un reparto de mercancías más sostenibles no sea el esperado.

Abstract Freight deliveries and sustainable urban development. Urban freight deliveries should be analyzed by focusing on the three sustainability axes: economic, social and environmental. Within the scope of sustainable urban development, it is important to develop an urban freight system that is sustainable and efficient, which is extremely complex due to the enormous variety of freight deliveries co-existing in a city and to the multiple stakeholder groups involved in the problem, which o en results in the appearance of conflict areas. is paper describes all that complexity and provides details on the main responses that may be given at the urban framework, both from the industry and from the local authority, always taking into account that the regulations imposed to achieve sustainability in urban freight deliveries might not result as expected.

Computers in Industry, 2016

Intermodal terminals are responsible for assigning routes to freight trains entering and leaving ... more Intermodal terminals are responsible for assigning routes to freight trains entering and leaving the facility, for establishing priority rules when there exist potential conflicts between trains, and for re-planning operations in the event of an incidence. Seeking to automate this process and to increase the efficiency and capacity of the system, we propose here a heuristic method to assign destination points inside the terminal to the inbound trains and to schedule the movements of inbound and outbound trains so that the delays derived from conflicts are minimized. This procedure, combined with navigation and ground hardware, has been implemented in the Seville port in Spain, and is successfully tested here for a series of congested scenarios.

Brazilian Journal of Operations & Production Management, 2016

The presented work is done for a company that currently operates twenty lines of passenger transp... more The presented work is done for a company that currently operates twenty lines of passenger transport in the metropolitan area of Seville. The planning of these was originally carried out manually, building routes and shifts in an Excel spreadsheet. In order to automate the process as much as possible. It was designed and implemented by a scheduling algorithm that would be much simple than other algorithms in the literature and that, in addition, would make it possible to allow mixing vehicles and drivers between the lines. The objective was, firstly, to employ the minimum number of drivers; then, it is trying to use the least possible number of vehicles; finally, the study tries to reduce as much as possible the amount of split shifts. In addition, restrictions on the design of routes and shifts were added. At all times the service frequencies remained above the set limit. To allow the possibility of unexpected demand peaks, was established in the capacity of each route some slack.

Brazilian Journal of Operations & Production Management, 2016

Purpose - Intermodal transport chains often appear as “black boxes” to the cargo owners and their... more Purpose - Intermodal transport chains often appear as “black boxes” to the cargo owners and their clients, who lose track of the container until it arrives at the final end of the chain. The paper discusses why a tracking and tracing system should represent an important added value for them.
Design/methodology/approach - We describe here the configuration and features of a novel low-cost system to track and trace containers in an intermodal supply chain, provide information to shippers regarding delays and other unexpected events, and assist terminal operations accordingly. We then analyze the positive impacts of such a system over the entire supply chain, identifying the requirements of the main chain actors regarding the availability of information and how the proposed system contributes to the fulfillment of those requirements.
Findings - The visibility of containers throughout the entire supply chain provides multiple benefits for shippers, terminals and transport providers.
Research limitations/implications - The operational and economic benefits of the system are clear, but the lack of historical data does not allow for a quantitative estimation of those foreseen benefits.
Practical implications - Intermodal terminals might see this type of information systems as an opportunity to generate added value for their customers, including shippers and carriers. In a scenario with high competition levels between terminals, this added value could represent the competitive advantage necessary to guarantee the growth of a terminal without requiring expensive investments and costs.
Originality/value - The paper describes the benefits provided by the system to the main stakeholders of the intermodal supply chain and provides some conclusions with respect to those benefits and to future developments.

International Journal of Bio-Inspired Computation, 2015

The intermodal transport chain can become more efficient by means of a good organization of the d... more The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This paper focuses on a new approach to tackle the daily drayage problem by the use of viral system (VS). VS is a novel bio-inspired approach that makes use of a virus-infection biological analogy that is producing very satisfactory results when dealing with complex problems with huge feasibility region.

Dirección y Organización, 2014

The sampling of the users comfort, allows observing and predicting the level of comfort on the HV... more The sampling of the users comfort, allows observing and predicting the level of comfort on the HVAC system. The development of online sampling systems assists in the recognition of the behaviour patterns that occur in the offices. This paper presents a methodology specially designed and developed in order to make easier knowledge extraction and representation, in this way it possible to make decisions about the comfort in buildings. The methodology used provides important and useful information to select the comfort set-point of the rooms of a central HVAC system without the need to use fixed values based on programmed time schedules or any other methodology. In this methodology, the users are evaluated by using a standard set of key questions in order to measure the level of satisfaction respect to environmental factors, thanks to a questionnaire of imprecise answers. We seek an improvement in the building users, regardless of their particularities.

Computer-Aided Civil and Infrastructure Engineering, 2013

Container terminals are designed to provide support for the continuous changes in container ships... more Container terminals are designed to provide support for the continuous changes in container ships. The most common schemes used for dock management are based on discrete and continuous locations. In view of the steadily growing trend in increasing container ship size, more flexible berth allocation planning is mandatory. The consideration of continuous location in the container terminal is a good option. This paper addresses the berth allocation problem with continuous dock, which is called dynamic berth allocation problem (DBAP). We propose a mathematical model and develop a heuristic procedure, based on a genetic algorithm, to solve the corresponding mixed integer problem. Allocation planning aims to minimise distances travelled by the forklifts and the quay crane, for container loading and unloading operations for each ship, according to the quay crane scheduling. Simulations are undertaken using Arena software, and experimental analysis is carried out for the most important container terminal in Spain.

Computers in Industry, 2013

The intermodal transport chain can become more efficient by means of a good organization of draya... more The intermodal transport chain can become more efficient by means of a good organization of drayage movements. Drayage in intermodal container terminals involves the pick up and delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This scheduling has traditionally been done once a day and, under these conditions, any unexpected event could cause timetable delays. We propose to use the real-time knowledge about vehicle position to solve this problem, which permanently allows the planner to reassign tasks in case the problem conditions change. This exact knowledge of the position of the vehicles is possible due to the use of a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that these additional data can be used to dynamically improve the solution.

DYNA, 2012

De la implantación de tecnologías y aplicaciones RFID se espera un cambio total de las operacione... more De la implantación de tecnologías y aplicaciones RFID se espera un cambio total de las operaciones logísticas, una vez superadas las limitaciones de costes, generando enormes beneficios en aspectos como control de inventario, trazabilidad o integración de la cadena de suministros. En cualquier caso, los primeros pasos de implementación del RFID pueden dar lugar a una serie de problemas y deficiencias operativas en los centros de distribución, no sólo relacionados con costes o gestión de la información, sino además con el diseño y la fiabilidad de los propios sistemas. Estos problemas pueden dar lugar a empeoramientos significativos del rendimiento, y deben ser tenidos en cuenta a la hora de plantear la introducción de la tecnología. Analizamos aquí los problemas a los que se tuvo que enfrentar una distribuidora de productos lácteos española durante un proyecto piloto de implantación de RFID en su sección de expediciones, cuantificados mediante los indicadores correspondientes.

Advanced Engineering Informatics, 2011

The intermodal transport chain can become more efficient by means of a good organization of the d... more The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. The literature shows some works on centralized drayage management, but most of them consider the problem only from a static and deterministic perspective, whereas the work we present here incorporates the knowledge of the real-time position of the vehicles, which permanently enables the planner to reassign tasks in case the problem conditions change. This exact knowledge of position of the vehicles is possible thanks to a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that this additional data can be used to dynamically improve the solution.

Dirección y Organización, 2011

The scheduling of transportation systems has traditionally been done once a day. At beginning of ... more The scheduling of transportation systems has traditionally been done once a day. At beginning of a working day, the planner establishes which tasks will be carried out by each vehicle. Then, traffic jam, breakdown and any unexpected problem will cause delays on our timetable. In this paper, we propose to use real-time vehicle position knowledge to solve this problem. So, the planner is permanently enabled to reallocate tasks as the problem conditions change. As both drayage problem is a NP-Hard problem and a high-speed procedure is required, exact methods are not computationally feasible. So, a heuristic algorithm has been implemented to perform the problem described.

Research in Transportation Economics, 2021

Aula Abierta, 2021

Aula Abierta, 2019

Dirección y Organización, 2019

Transport, 2018

Complexity, Feb 8, 2018

Journal of Navigation, 2018

Journal of Transport Geography, Feb 2017

Revista Transporte y Territorio, 2017

Computers in Industry, 2016

Brazilian Journal of Operations & Production Management, 2016

International Journal of Bio-Inspired Computation, 2015

Dirección y Organización, 2014

Computer-Aided Civil and Infrastructure Engineering, 2013

Computers in Industry, 2013

DYNA, 2012

Advanced Engineering Informatics, 2011

The intermodal transport chain can become more efficient by means of a good organization of the d... more The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. The literature shows some works on centralized drayage management, but most of them consider the problem only from a static and deterministic perspective, whereas the work we present here incorporates the knowledge of the real-time position of the vehicles, which permanently enables the planner to reassign tasks in case the problem conditions change. This exact knowledge of position of the vehicles is possible thanks to a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that this additional data can be used to dynamically improve the solution.

Dirección y Organización, 2011

Engineering Digital Transformation, Lecture Notes in Management and Industrial Engineering, 2019

The experience is described in this paper, it is a small game for drawing a little house. The exp... more The experience is described in this paper, it is a small game for drawing a little house. The experience tries to innovate in the traditional methodologies of learning of theoretical subjects and is shown a small game that can be used to intro

Lecture Notes in Management and Industrial Engineering, 2019

Drayage is the stage of the intermodal transport that deals with transport of freight on trucks a... more Drayage is the stage of the intermodal transport that deals with transport of freight on trucks among the intermodal terminal, and customers and suppliers that are located in its hinterland. This work proposes an algorithm based on simulated annealing heuristics to solve the operations of drayage. This algorithm has been used to solve battery problems, demonstrating the validity and suitability of its results, which were compared with exact method.

X Congreso Ingeniería del Transporte, 2012

Las terminales de contendores portuarias han diseñando sus muelles de forma que puedan adaptarse ... more Las terminales de contendores portuarias han diseñando sus muelles de forma que puedan adaptarse fácilmente a los continuos cambios en el tamaño de los buques portacontenedores, conocido como fenómeno del gigantismo. Un muelle de línea continua de atraque es la solución para que los puertos puedan recibir tanto grandes barcos como buques pequeños. En este trabajo se realiza el análisis de la operativa de buque y la gestión de muelles en la terminal de contenedores del puerto de Algeciras. Para esto es propuesto un modelo de simulación discreta utilizando el software ARENA 11.0. El objetivo es analizar el comportamiento del puerto ante posibles incrementos en el tráfico de buques y contenedores.

Computer-Aided Civil and Infrastructure Engineering, 2013

The Sixth International Conference on City Logistics, 2009

In medium and large cities, the delivery of goods represents a significant contribution to the pr... more In medium and large cities, the delivery of goods represents a significant contribution to the problems of congestion, lack of parking, pollution and energy consumption. The characteristics of this type of transport are also very different from passenger mobility, even though they are often assimilated, due to the lack of specific tools for estimation and analysis, and also of indicators to evaluate improvements in the systems of urban goods distribution. In this work, we start by developing a systematic model to estimate the transport of goods in a city, according to the particularities of its supply and demand. This model can then be used to determine with a high level of detail the contribution of the delivery of goods to the ecological footprint of the city, thus proposed as the key indicator of the efficiency of this type of transport. The work is applied to the city of Seville, in Spain.

5th International Conference on Industrial Engineering and Industrial Management. XV Congreso de Ingeniería de Organización, 2011

El modelo planteado resuelve el problema del acarreo en un entorno donde los tiempos de transito ... more El modelo planteado resuelve el problema del acarreo en un entorno donde los tiempos de transito de nuestros viajes no son deterministas, sino que presentan una cierta aleatoriedad. Para resolver el inconveniente del desconocimiento a priori de la duración de los viajes, se hace uso de la información que las nuevas tecnologías pueden proporcionar, gracias a las cuales se tiene conocimiento exacto de la posición de la flota y comunicación permanente con todos los conductores. De este modo, se podrán modificar la planificación diaria dependiendo de las circunstancias que se vayan produciendo a lo largo del día.

The Sixth International Conference on City Logistics, 2009

An improvement on drayage operations is necessary for freight intermodal transport to become comp... more An improvement on drayage operations is necessary for freight intermodal transport to become competitive. When drayage is happening into cities or urban centres the transit time is usually random. Then the optimal fleet scheduling is very difficult to find, and it could change during the day. The work we present here is a dynamic optimization model which uses real-time knowledge of the fleet’s position, permanently enabling the planner to reallocate tasks as the problem conditions change. Stochastic trip times are considered, both in the completion of each task and between tasks; and the tasks can be flexible or well-define. We describe the algorithm in detail for a test problem and then apply it to a set of random drayage problems of different size and characteristics, obtaining significant cost reductions with respect to initial estimations.

6th International Conference on Industrial Engineering and Industrial Management. XVI Congreso de Ingeniería de Organización., 2012

In this paper we study the berth allocations problems in the Seville con- tainer terminal. We pro... more In this paper we study the berth allocations problems in the Seville con- tainer terminal. We proposal simulation and optimization models with arena soft- ware, and develop a heuristic procedure based on genetic algorithm for solved the problems. We conduct a large amount of computational experiments to validate the models proposals.

6th International Conference on Industrial Engineering and Industrial Management. XVI Congreso de Ingeniería de Organización., 2012

In this paper we study the berth allocations problems in the Algeciras container terminal. We pro... more In this paper we study the berth allocations problems in the Algeciras container terminal. We proposal simulation and optimization models with arena software, and develop a heuristic procedure based on genetic algorithm for solved the problems. We conduct a large amount of computational experiments with three different scenarios to validate the models proposals.

6th International Conference on Industrial Engineering and Industrial Management. XVI Congreso de Ingeniería de Organización., 2012

The freight transportation is one of the main sectors in the European Un-ion. In the last decades... more The freight transportation is one of the main sectors in the European Un-ion. In the last decades, it grew up more than theGPB.This growth was not proportional on all the transportation modes. It has associated negative effects: accidents, pollution and congestion. The UE looked to the intermodality like the main alternative. However, the crisis in Europe do not possible the inversion on great infrastructure. This work pretends to optimize and improve the use of the inter-modality through the drayage.

Third World Congress on Nature and Biologically Inspired Computing (NaBIC), 2011

The scheduling of transportation systems has traditionally been done once a day. At beginning of ... more The scheduling of transportation systems has traditionally been done once a day. At beginning of a working day, the planner establishes which tasks will be carried out by each vehicle. Then, traffic jam, breakdown and any unexpected problem will cause delays on our timetable. In this paper, we propose to use real-time vehicle position knowledge to solve this problem. So, the planner is permanently enabled to reallocate tasks as the problem conditions change. As both drayage problem is a NP-Hard problem and a high-speed procedure is required, exact methods are not computationally feasible. So, a genetic algorithm has been implemented to perform the problem described.

World Automation Congress (WAC 2010), 2010

Proper planning of drayage operations is fundamental in the quest for the economic viability of i... more Proper planning of drayage operations is fundamental in the quest for the economic viability of intermodal freight transport. The work we present here is a dynamic optimization model which uses real-time knowledge of the fleet’s position, permanently enabling the planner to reallocate tasks as the problem conditions change. Stochastic trip times are considered, both in the completion of each task and between tasks

The intermodal transport chain can become more efficient by means of a good organization of the d... more The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations. There are some works on centralised drayage management, but most of them consider the problem only from a static and deterministic perspective. The main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. The work we present here considers the knowledge of the vehicles' real-time position, which permanently enables the planner to reassign tasks in case the problem conditions change. This exact knowledge of position of the vehicles is possible thanks to a geographic positioning system by satellite (GPS, Galileo, Glonass). This additional data are used to dynamically improve the solution.

IX Congreso de Ingeniería del Transporte. "Transporte sostenible y accesible. Retos tecnológicos, de gestión y recursos", 2010

Este articulo resuelve el problema del acarreo en una red con enlaces cuya duración es estocástic... more Este articulo resuelve el problema del acarreo en una red con enlaces cuya duración es estocástica. Y pone de relieve la importancia del conocimiento en tiempo real de la posición exacta de los vehículos de la flota para llevar a cabo una correcta asignación de tareas a la misma. El modelo tiene un carácter dinámico al ser capaz de reasignar tareas a medida que se conocen datos con mayor certeza.

International Conference on Harbor, Maritime & Multimodal Logistics Modelling ans Simulation, 2009

Industrial Engineering: A way for sustainable development. Book of 3rd International Conference on Industrial Engineering and Industrial Management. XIII Congreso de Ingeniería de Organización, 2009

Palabras clave: Intermodalidad, plataformas logística.

Palabras clave: Redes ferroviarias, fiabilidad, puntualidad.

Palabras clave: transporte intermodal, acarreo, metaheurísticas, tiempo de transito estocásticos

Palabras clave: Redes ferroviarias, fiabilidad, puntualidad.

II International Conference on Industrial Engineering and Industrial Management. XII Congreso de Ingeniería de Organización. Approaches and Trends on Current Organization Engineering, Sep 2008

La mayoría de las actividades del sector servicios se caracterizan por la simultaneidad en la pr... more La mayoría de las actividades del sector servicios se caracterizan por la simultaneidad en la producción y el consumo del servicio prestado, careciendo de un procedimiento de almacenamiento del producto como en el sector industrial. Este sector combina una capacidad constante de oferta del servicio con una demanda variable del mismo, lo cual genera un problema de optimización del uso de los recursos disponibles cuya solución permitiría obtener el máximo beneficio de las empresas. Para llevar a cabo esta tarea se introduce un sistema que gestiona los recursos de la empresa llamado Yield Management, con el propósito de inducir a las compañías a vender la unidad correcta de inventario al tipo de cliente adecuado, en el instante preciso y al precio conveniente. El objetivo de este trabajo ha sido estudiar la forma de simular distintos modelos de asignación de inventario, plazas de aparcamiento, aproximándose los más posible al funcionamiento real de un aparcamiento, con el consecuente análisis de distintos indicadores, como la ocupación y los ingresos que se obtienen con cada uno de los modelos, con el objetivo final de compararlos y decidir cuál es la mejor alternativa para la gestión del parking.

1st WSEAS International Conference on MARITIME and NAVAL SCIENCE and ENGINEERING (MN'08), 2008

Lately Maritime research areas have moved their interests to cover new areas conferring a more ge... more Lately Maritime research areas have moved their interests to cover new areas conferring a more general character to them. BOYAS project is proposed including these new perspectives as well as the classical ones. Trying to get this integral character for the waterway ambient and its activities management, the convergence between Multiagent Systems and Wireless Sensor Networks is studied.

Conference: II International Conference on Industrial Engineering and Industrial Management. XII Congreso de Ingeniería de Organización. Approaches and Trends on Current Organization Engineering, 2008

Los sistemas RFID son sistemas de IDentificación por RadioFrecuencia. Un correcto uso de la iden... more Los sistemas RFID son sistemas de IDentificación por RadioFrecuencia. Un correcto uso de la identificación por radio frecuencia puede ser de gran ayuda en la gestión de la cadena de suministro agroalimentaria y dar un gran valor añadido a los productos que esta industria provee. Para constatar las benevolencias de la tecnología en un entorno real se desarrollo el proyecto SIRECA, dando como resultado un previsible ahorro de tiempo y errores en el control de expediciones, gracias a un sistema RFID.