Comunicaciones y ponencias de congresos DEIM - EIMS Biltzarretako komunikazioak eta txostenak

Permanent URI for this collection

http://hdl.handle.net/2454/29491

Browse

Now showing 1 - 20 of 48

Open Access
Agent-based simulation improves e-grocery deliveries using horizontal cooperation
(IEEE, 2020) Serrano Hernández, Adrián; Faulín Fajardo, Javier; Torre Martínez, Rocío de la; Cadarso, Luis; Estatistika, Informatika eta Matematika; Enpresen Kudeaketa; Institute of Smart Cities - ISC; Institute for Advanced Research in Business and Economics - INARBE; Estadística, Informática y Matemáticas; Gestión de Empresas
E-commerce has increased tremendously in recent decades because of improvements in the information and telecommunications technology along with changes in societal lifestyles. More recently, e-grocery (groceries purchased online) including fresh vegetables and fruit, is gaining importance as the most-efficient delivery system in terms of cost and time. In this respect, we evaluate the effect of cooperation-based policies on service quality among different supermarkets in Pamplona, Spain. Concerning the methodology, we deploy, firstly, a detailed survey in Pamplona in order to model e-grocery demand patterns. Secondly, we develop an agent-based simulation model for generating scenarios in cooperative and non-cooperative settings, considering the real data obtained from the survey analysis. Thus, a Vehicle Routing Problem is dynamically generated and solved within the simulation framework using a biased-randomization algorithm. Finally, the results show significant reductions in lead times and better customer satisfaction when employing horizontal cooperation in e-grocery distribution.
Open Access
Aggregation functions based on the Choquet integral applied to image resizing
(Atlantis Press, 2019) Bueno, Jéssica C. S.; Dias, Camila A.; Pereira Dimuro, Graçaliz; Santos, Helida; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas
The rising volume of data and its high complexity has brought the need of developing increasingly efficient knowledge extraction techniques, which demands efficiency both in computational cost and in accuracy. Most of problems that are handled by these techniques has complex information to be identified. So, machine learning methods are frequently used, where a variety of functions can be applied in the different steps that are employed in their architecture. One of them is the use of aggregation functions aiming at resizing images. In this context, we introduce a study of aggregation functions based on the Choquet integral, whose main characteristic in comparison with other aggregation functions is that it considers, through fuzzy measure, the interaction between the elements to be aggregated. Thus, our main goal is to present an evaluation study of the performance of the standard Choquet integral the and copula-based generalization of the Choquet integral in relation to the maximum and mean functions, looking for results that may be better than the aggregation functions commonly applied. The results of such comparisons are promising, when evaluated through image quality metrics.
Open Access
Aggregation of deep features for image retrieval based on object detection
(Springer, 2019-09-22) Forcén Carvalho, Juan Ignacio; Pagola Barrio, Miguel; Barrenechea Tartas, Edurne; Bustince Sola, Humberto; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Image retrieval can be tackled using deep features from pretrained Convolutional Neural Networks (CNN). The feature map from the last convolutional layer of a CNN encodes descriptive information from which a discriminative global descriptor can be obtained. However, this global descriptors combine all of the information of the image, giving equal importance to the background and the object of the query. We propose to use an object detection based on saliency models to identify relevant regions in the image and therefore obtain better image descriptors. We extend our proposal to multi-regional image representation and we combine our proposal with other spatial weighting measures. The descriptors derived from the salient regions improve the performance in three well known image retrieval datasets as we show in the experiments.
Open Access
Análisis de los cambios en los patrones de temperatura mediante técnicas de stream clustering
(CAEPIA, 2024) Urío Larrea, Asier; Pereira Dimuro, Graçaliz; Andreu-Pérez, Javier; Camargo, Heloisa A.; Aguirre Eraso, Javier; Bustince Sola, Humberto; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
El cambio climático afecta a las condiciones medioambientales de las distintas regiones. La capacidad de constatar estos cambios es una eficaz herramienta para adaptarse a la evolución de las condiciones. Los datos meteorológicos se generan continuamente en múltiples estaciones de todo el mundo, proporcionando una valiosa información sobre la variabilidad en el tiempo de los patrones climáticos. El estudio de este flujo de datos nos permite comprender mejor los nuevos patrones climáticos. Este trabajo explora, mediante un algoritmo de agrupamiento de flujos de datos (stream clustering), el potencial de emplear datos meteorológicos obtenidos en diferentes localizaciones geográficas para rastrear el cambio en los patrones climáticos en la Comunidad Foral de Navarra durante los últimos 20 años. El estudio de caso mostró la aplicabilidad de los métodos de flujos de datos a la segmentación incremental de regiones geográficas en función de sus factores climatológicos.
Open Access
Analysing capacity challenges in the Multi-Airport System of Mexico City
(Dime University of Genoa, 2022) Mújica Mota, Miguel; Faulín Fajardo, Javier; Izco Berastegui, Irene; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
The relentless growth in Mexico City’s aviation traffic has inevitably strained capacity development of its airport, raising the dilemma between the possible solutions. In the present study, Mexico’s Multi-Airport System is subjected to analysis by means of multi-model simulation, focusing on the capacity-demand problem of the system. The methodology combines phases of modelling, data collection, simulation, experimental design, and analysis. Drawing a distinction from previous works involving two-airport systems. It also explores the challenges raised by the Covid-19 pandemic in Mexico City airport operations, with a discrete-event simulation model of a multi-airport system composed by three airports (MEX, TLC, and the new airport NLU). The study is including the latest data of flights, infrastructures, and layout collected in 2021. Therefore, the paper aims to answer to the question of whether the system will be able to cope with the expected demand in a short-, medium-, and long term by simulating three future scenarios based on aviation forecasts. The study reveals potential limitations of the system as time evolves and the feasibility of a joint operation to absorb the demand in such a big region like Mexico City
Open Access
Analysis of inter-train wireless connectivity to enable context aware rail applications
(Springer, 2021) Picallo Guembe, Imanol; López Iturri, Peio; Celaya Echarri, Mikel; Azpilicueta Fernández de las Heras, Leyre; Astrain Escola, José Javier; Falcone Lanas, Francisco; Estadística, Informática y Matemáticas; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Estatistika, Informatika eta Matematika; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Train systems are fundamental players within multi-modal transit systems, providing efficient transportation means for passengers and goods. In the framework of Smart Cities and Smart Regions, providing context aware environments is compulsory in order to take full advantage of system integration, with updated information exchange among Intelligent Transportation system deployments. In this work, inter-train wireless system connectivity is analyzed with the aid of deterministic 3D wireless channel approximations, with the aim of obtaining estimations of frequency/power volumetric channel distributions, as well as time domain characteristics, for different frequency bands. The results show the impact of the complex inter-train scenario conditions, which require precise channel modelling in order to perform optimal network design, planning and optimization tasks.
Open Access
Analysis of interaction mechanisms and intercomparison of raytracing tools for optimizing THz simulations
(IEEE, 2025-03-11) Aksoy, Enes; Schultze, Alper; Fazli, Abdolvakil; Raschkowski, Leszek; Azpilicueta Fernández de las Heras, Leyre; Celaya Echarri, Mikel; Navarro Cía, Miguel; Stanczak, Slawomir; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
This paper quantifies the weight of the different physical mechanisms (reflection, diffraction, and scattering) in a typical indoor THz wireless communication environment and provides an intercomparison of raytracing tools. Two state-of-the-art raytracing tools - Wireless InSite and Sionna - are utilized to analyze the capabilities of currently available open-source and commercial raytracing engines for THz simulations. A channel sounder measurement campaign at 300 GHz was conducted in a conference room at Fraunhofer HHI, which is used to validate the raytracing simulations. Additionally, the measurements are compared to a proprietary raytracer, optimized for THz simulations. This paper presents a guideline to increase the capabilities of state-of-the-art raytracing tools, to obtain good results for high frequency simulations. The comparisons show, that currently used raytracing tools are not sufficiently accurate for THz simulations. However, these inaccuracies can be mitigated by the implementation of new features, such as the inclusion of different scattering mechanisms and the incorporation of atmospheric attenuation, while utilizing precise geometry and accurate material parameter models.
Open Access
Assessing the impact of physicians' behavior variability on performance indicators in emergency departments: an agent-based model
(IEEE, 2025-01-20) Baigorri Iguzquiaguirre, Miguel; Cildoz Esquíroz, Marta; Mallor Giménez, Fermín; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
In emergency departments (EDs), traditional simulation models often overlook the variability in physician practice, assuming uniform service provision. Our study introduces a hybrid agent-based discrete-event simulation (AB-DES) model to capture this variability. Through simulation scenarios based on real ED data, we assess the impact of physician behavior on key performance indicators such as patient waiting times and physician stress levels. Results show significant variability in both individual physician performance and average metrics across scenarios. By integrating physician agent modeling, informed by literature from medical and workplace psychology, our approach offers a more nuanced representation of ED dynamics. This model serves as a foundation for future developments towards digital twins, facilitating real-time ED management. Our findings emphasize the importance of considering physician behavior for accurate performance assessment and optimization.
Open Access
Bargaining for the last mile cost and environmental preferences of stakeholders: an economic experiment
(Elsevier, 2025-01-09) Denant-Boemont, Laurent; Faulín Fajardo, Javier; Hammiche, Sabrina; Serrano Hernández, Adrián; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
We aim at studying how environmental preferences matter when consumers negotiate with sellers in order to contract for delivery at home. To do that, we build an economic laboratory experiment where pairs of participants bargain for choosing either the click-and-collect option, which is free for consumer but implies for him private transportation costs, or the delivery-at-home option, which is pricey for him, but externalize transportation cost to the seller. In addition, in our game, transportation triggers environmental costs that are borne by both partners. We have 4 different treatments: The first one, as a benchmark, corresponds to an ultimatum bargaining game about the last mile cost with environmental costs. In the second one, we deliver a message about environmental impacts of transportation to the buyer, whereas, in the third one, the same message is delivered to the seller. The last one is a control where the message is delivered to both partners. The preliminary results (which included 178 participants) show that the average delivery price proposed by sellers is below Nash equilibrium price but above the "behavioral price" and that acceptance rates of seller's proposals by buyers are quite high.
Open Access
Cognitive assistant for physical exercise monitoring in hand rehabilitation
(Springer, 2023-08-21) Rincón Arango, Jaime Andrés; Marco Detchart, Cedric; Julian, Vicente; Carrascosa, Carlos; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
This paper introduces a novel, affordable companion robot that has been designed for rehabilitation purposes among the elderly population. The robot is equipped with a camera that records exercises, and an animation screen that delivers clear and easy-to-follow instructions and feedback. To evaluate the device, a machine learning algorithm was used on a dataset of therapy exercises. The results indicate that the robot effectively recognizes gestures and accurately identifies the exercises being performed. This study presents a groundbreaking and cost-effective solution for elderly rehabilitation and has the potential to revolutionize the industry with its cutting-edge technology.
Open Access
Comparison of experiment and simulation of ultrasonic mid-air haptic forces
(IEEE, 2022) Morales González, Rafael; Georgiou, Orestis; Marzo Pérez, Asier; Frier, William; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Ultrasound mid-air haptics is an emerging technology with many applications in human-computer interactions. Despite great advances in related hardware and software, physics models that predict the resulting forces on a surface (e.g., someone's hand) are either too simple (inaccurate) or too complex (computationally expensive). In this paper, we show that simple models are not sufficient when predicting the force on an experimental setup involving two prototype devices and a precision scale. Specifically, we demonstrate that our experimental measurements cannot be accurately predicted using a linear acoustic model.
Open Access
d-CC integrals: generalizing CC-integrals by restricted dissimilarity functions with applications to fuzzy-rule based systems
(Springer, 2023) Sartori, Joelson; Asmus, Tiago da Cruz; Santos, Helida; Borges, Eduardo N.; Bustince Sola, Humberto; Dimuro, Graçaliz Pereira; Lucca, Giancarlo; Bedregal, Benjamin; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
The discrete Choquet Integral (CI) and its generalizations have been successfully applied in many different fields, with particularly good results when considered in Fuzzy Rule-Based Classification Systems (FRBCSs). One of those functions is the CC-integral, where the product operations in the expanded form of the CI are generalized by copulas. Recently, some new Choquet-like operators were developed by generalizing the difference operation by a Restricted Dissimilarity Function (RDF) in either the usual or the expanded form of the original CI, also providing good results in practical applications. So, motivated by such developments, in this paper we propose the generalization of the CC-integral by means of RDFs, resulting in a function that we call d-CC-integral. We study some relevant properties of this new definition, focusing on its monotonicity-like behavior. Then, we proceed to apply d-CC-integrals in a classification problem, comparing different d-CC-integrals between them. The classification acuity of the best d-CC-integral surpasses the one achieved by the best CC-integral and is statistically equivalent to the state-of-the-art in FRBCSs.
Open Access
De funciones de equivalencia restringida en Lⁿ a medidas de similitud entre multiconjuntos difusos
(CAEPIA, 2024) Ferrero Jaurrieta, Mikel; Rodríguez Martínez, Iosu; Bernardini, Ángela; Fernández Fernández, Francisco Javier; López Molina, Carlos; Bustince Sola, Humberto; Takáč, Zdenko; Marco Detchart, Cedric; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Este artículo es un resumen del trabajo publicado en la revista IEEE Transactions on Fuzzy Systems. En este trabajo, presentamos una contribución a la teoría de las Funciones de Equivalencia Restringida (REF), que permite comparar elementos multivaluados. Extendemos el concepto de REF de L a Ln y presentamos una nueva construcción de similitud en Ln. A partir de esta filosofía se construyen medidas de similitud entre multiconjuntos difusos y se presenta un ejemplo aplicado en el contexto de la difusión anisotrópica de imágenes en color.
Open Access
Demonstration of XRStudio tools for creation of room-size immersive experiences within an extended reality environment
(Association for Computing Machinery, 2023) Ardaiz Villanueva, Óscar; Olaz Moratinos, Xabier; Benbelkheir Núñez, Youssef; Lerga Armendáriz, Álvaro; Gasco González, Lucas; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Immersive experiences are mostly created with desktop-based tools using flat displays, mouse and keyboard; as a result immersive experiences have a 2D look and interaction: user sit or stand looking forward, and interact with elements within reach of their arms as in a desktop. The objective of this work is to facilitate creating room-size immersive experiences that take advantage of tethered head mounted displays and hand-held controllers to create while walking freely in space with full body movement freedom. To this end we propose XRStudio, a set of tools that permit to create within an extended reality environment so that authors can walk to move objects in space or manipulate elements with hand and full body movements as in the real world.
Open Access
Development of a cognitive IoT-enabled Smart Campus
(IEEE, 2024-08-23) Picallo Guembe, Imanol; Klaina, Hicham; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Celaya Echarri, Mikel; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Ciencias; Zientziak; Institute of Smart Cities - ISC
The evolution from Smart to Cognitive Cities takes advantage, among others, of advanced communication technologies in order to increase interactivity levels. In this work, an analysis of wireless connectivity within the framework of a Smart Campus pilot at the Public University of Navarra in Spain is presented. By means of in-house implemented hybrid deterministic code, multiple wireless connectivity conditions with different operating frequencies are presented. The use of these tools provides accurate coverage/capacity analysis of large, complex scenarios, aiding in the design of network devices as well as overall network topology in order to optimize overall performance.
Open Access
Directions of directional, ordered directional and strengthened ordered directional increasingness of linear and ordered linear fusion operators
(IEEE, 2019) Sesma Sara, Mikel; Marco Detchart, Cedric; Lafuente López, Julio; Roldán López de Hierro, Antonio Francisco; Mesiar, Radko; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this work we discuss the forms of monotonicity that have been recently introduced to relax the monotonicity condition in the definition of aggregation functions. We focus on directional, ordered directional and strengthened ordered directional monotonicity, study their main properties and provide some results about their links and relations among them. We also present two families of functions, the so-called linear fusion functions and ordered linear fusion functions and we study the set of directions for which these types of functions are directionally, ordered directionally and strengthened ordered directionally increasing. In particular, OWA operators are an example of ordered linear fusion functions.
Open Access
Diseño y captura de una base de datos para el reconocimiento de emociones minimizando sesgos
(CAEPIA, 2024) Jurío Munárriz, Aránzazu; Pascual Casas, Rubén; Domínguez Catena, Iris; Paternain Dallo, Daniel; Galar Idoate, Mikel; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertistate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
El reconocimiento de emociones a partir de expresiones faciales (FER) es un campo de investigación importante para la interacción persona-máquina. Sin embargo, los conjuntos de datos utilizados para entrenar modelos FER a menudo contienen sesgos demográficos que pueden conducir a la discriminación en el modelo final. En este trabajo, presentamos el diseño y la captura realizados para la creación de una nueva base de datos para FER, donde tratamos de minimizar los sesgos desde el propio diseño. La base de datos se ha creado utilizando diferentes métodos de captura. Para comprobar la reducción de los sesgos alcanzada, analizamos diferentes métricas de sesgo representacional y estereotípico sobre la base de datos generada y la comparamos frente a otras bases de datos estándar en la literatura de FER.
Open Access
Distributed opportunistic wireless mapping system towards smart city service provision
(IEEE, 2021) Villadangos Alonso, Jesús; Falcone Lanas, Francisco; López Martín, Antonio; Astrain Escola, José Javier; Sanchis Gúrpide, Pablo; Matías Maestro, Ignacio; Estatistika, Informatika eta Matematika; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Ingeniería Eléctrica, Electrónica y de Comunicación
The knowledge of wireless signal distribution within an urban scenario can provide useful information to users as well as to enhance connectivity and device operation or to perform municipal logistics based on crowd density and user mobility patterns. In this work, a distributed wireless mapping system, based on a combination of opportunistic nodes such as smartphones which map geolocated WiFi access point connection and received power levels, and a cloud-based information gathering architecture is described. The proposed system has been tested in the framework of the Smart City platform of the city of Pamplona, providing signal distribution heat maps, which can be used for multiple municipal services.
Open Access
An empirical study on supervised and unsupervised fuzzy measure construction methods in highly imbalanced classification
(IEEE, 2020) Uriz Martín, Mikel Xabier; Paternain Dallo, Daniel; Bustince Sola, Humberto; Galar Idoate, Mikel; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
The design of an ensemble of classifiers involves the definition of an aggregation mechanism that produces a single response obtained from the information provided by the classifiers. A specific aggregation methodology that has been studied in the literature is the use of fuzzy integrals, such as the Choquet or the Sugeno integral, where the associated fuzzy measure tries to represent the interaction existing between the classifiers of the ensemble. However, defining the big number of coefficients of a fuzzy measure is not a trivial task and therefore, many different algorithms have been proposed. These can be split into supervised and unsupervised, each class having different learning mechanisms and particularities. Since there is no clear knowledge about the correct method to be used, in this work we propose an experimental study for comparing the performance of eight different learning algorithms under the same framework of imbalanced dataset. Moreover, we also compare the specific fuzzy integral (Choquet or Sugeno) and their synergies with the different fuzzy measure construction methods.
Open Access
Enabling anything to anything connectivity within urban environments towards cognitive frameworks
(IEEE, 2024-08-23) Picallo Guembe, Imanol; Klaina, Hicham; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Celaya Echarri, Mikel; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Ciencias; Zientziak; Institute of Smart Cities - ISC
The evolution from Smart Cities towards Cognitive Cities is enabled, among others, by the use of flexible and adaptive communication systems, capable of providing high levels of interactivity among multiple systems and users. In this work, wireless connectivity in full volumetric scale is analyzed, in order to provide wireless links between any device/user within the scenario, spanning to different applications from vehicular connectivity at different levels or infrastructure related communications, among others.