Clasificaciones deportivas y búsquedas en internet. Asomándote a las redes complejas

Recientemente se ha acuñado el término Redes complejas para referirse a una moderna rama de la Física que trata de modelar las interrelaciones entre los elementos de un conjunto finito de objetos con el fin de observar el comportamiento emergente resultante. A pesar del respeto que produce la palabra complejidad, en este artículo nos asomamos brevemente mediante algunos ejemplos que: i) interesarán al alumno y ii) utilizan técnicas algebraicas sencillas. Este artículo está pensado como una clase motivadora para el Álgebra Matricial, asignatura que forma parte del currículo en las Escuelas y Facultades universitarias. Aquí, se ha aplicado en la asignatura Álgebra del Grado en Ingeniería Física de la UPV. Los ejemplos considerados incluyen dos elementos motivadores: las clasificaciones deportivas y las búsquedas por internet. En el desarrollo, se muestra la necesidad de determinadas herramientas avanzadas (que forman parte esencial en la asignatura), lo que estimula el interés de aprender tales herramientas.Izquierdo Sebastián, J. (2022). Clasificaciones deportivas y búsquedas en internet. Asomándote a las redes complejas. http://hdl.handle.net/10251/182004DE

Sistemas dinámicos lineales discretos. Una primera pincelada

Uno de los aspectos fundamentales de la educación universitaria es la motivación. En algunos elementos básicos de primeros cursos de Escuelas Técnicas, tales como el Álgebra Matricial, puede resultar difícil captar la atención del alumnado y crear una motivación suficiente hacia una asignatura que, en principio, puede parecer alejada de los aspectos prácticos que el alumno espera en una carrera técnica. Se hace, pues, necesario disponer de recursos eficientes de motivación. Dado el reducido bagaje formativo del alumno, se debe proponer problemas de relevancia que: i) le puedan interesar y ii) utilicen técnicas algebraicas sencillas. Este artículo presenta el contenido de una posible primera clase para un curso de Álgebra Matricial, perfectamente apta en diversas Escuelas y Facultades universitarias. Aquí, se ha aplicado en la asignatura Álgebra del Grado en Ingeniería Física de la UPV. El problema, centrado en sistemas dinámicos sencillos, es conceptualmente asequible para los alumnos. No obstante, en el desarrollo, se muestra la necesidad de determinadas herramientas avanzadas (que forman parte esencial en la asignatura), lo que estimula el interés de aprender tales herramientas.Izquierdo Sebastián, J. (2022). Sistemas dinámicos lineales discretos. Una primera pincelada. http://hdl.handle.net/10251/182009DE

E-Learning In Continuous Professional Development Across The Globe. An experience in Water Engineering

[EN] Based on our wide experience in continuous professional development (CPD) through traditional activities and hands-on experience on several commonly used Learning Management Systems, we have integrated both concepts and developed a simple, yet effective e-learning approach to help professionals in the water field to fill the gap between their sometimes not updated background and the new features that characterize the water field in the present days. We argue that this task can make use of the same approach that is essential to the knowledge discovery process, to which the e-learning process boils down to. In this contribution we present the work performed at the Polytechnic University of Valencia, within the Multidisciplinary Team of Fluid Modelling, on web systems to support technology enhanced learning specifically addressed to professionals in the Water field. Our approach hinges on the joint use of the online as well as the offline characteristics of the e-learning proces s and puts to work together in a synergic way both traditional and technology-based learning know-how. As a result, a number of distance courses have been produced that are used for Engineering CPD across the globe, since many professionals worldwide, mainly from Spanish speaking countries, have followed our courses. We present the evolution of our system and the results obtained from testing and evaluating the prototype during the last three years. We have identified issues significant to users in order to better manage the system and changes required to adapt our system to organizational processes and context. Feedback received from trainees indicates both the validity of our approach and the feasibility of implementing e-learning materials to contribute to CPD in the water field in particular and in any field in general, since the methodology herein presented can be exported in a straightforward manner.This work has been performed under the support of the projects Investigación Interdisciplinar nº 5706 (UPV) and DPI2004-04430 of the Dirección General de Investigación del Ministerio de Educación y Ciencia (Spain) and FEDER funds.Izquierdo Sebastián, J.; López Jiménez, PA.; Fuertes-Miquel, VS.; Izquierdo Sebastián, FJ. (2018). E-Learning In Continuous Professional Development Across The Globe. An experience in Water Engineering. WEBIST. 3:383-390. https://doi.org/10.5220/0001269803830390S383390

Improved pairwise comparison transitivity using strategically selected reduced information

The research is financially supported by the Czech Science Foundation, Grant No. 19-06569S.Benítez López, J.; Carpitella, S.; Izquierdo Sebastián, J. (2021). Improved pairwise comparison transitivity using strategically selected reduced information. Universitat Politècnica de València. 106-110. http://hdl.handle.net/10251/182210S10611

Funciones test para optimización mono-objetivo

Para resolver la mayor parte de problemas de optimización del mundo real son necesarias técnicas sofisticadas, tales como los algoritmos evolutivos, que no se basan en el Cálculo Infinitesimal y que, en consecuencia, nunca caben en los planes de estudios de los grados en ciencia e ingeniería. No obstante, el ingeniero tendrá que utilizar tales técnicas antes o después. Para poner a prueba la habilidad de tales técnicas de optimización se suelen utilizar problemas de benchmarking que exhiben algunas de las características de los problemas del mundo real. En este artículo enumeramos brevemente algunas de tales características y presentamos una colección de problemas de optimización mono-objetivo, no condicionada, en varias variables.Izquierdo Sebastián, J.; Carpitella, S. (2018). Funciones test para optimización mono-objetivo. http://hdl.handle.net/10251/105210DE

Joint operation of pressure reducing valves and pumps for improving the efficiency of water distribution systems

[EN] New environmental paradigms imposed by climate change and urbanization processes are leading cities to rethink urban management services. Propelled by technological development and the internet of things, an increasingly smart management of cities has favored the emergence of a new research field, namely, the smart city. Within this new way of considering cities, smart water systems are emerging for the planning, operation, and management of water distribution networks (WDNs) with maximum efficiency derived from the application of data analysis and other information technology tools. Considering the possibility of improving WDN operation using available demand data, this work proposes a hybrid and near-real-time optimization algorithm to jointly manage pumps working with variable speed drives and pressure-reducing valves for maximum operational efficiency. A near-real-time demand forecasting model is coupled with an optimization algorithm that updates in real time the water demand of the hydraulic model and can be used to define optimal operations. The D-town WDN is used to validate the proposal. The number of control devices in this WDN makes real time control especially complex. Warm solutions are proposed to cope with this feature as they reduce the computational effort needed if suitably tuned. In addition to energy savings of around 50%, the methodology proposed in this paper enables an efficient system pressure management, leading to significant leakage reduction.Brentan, BM.; Meirelles, G.; Luvizotto, E.; Izquierdo Sebastián, J. (2018). Joint operation of pressure reducing valves and pumps for improving the efficiency of water distribution systems. Journal of Water Resources Planning and Management. 144(9):04018055-1-04018055-12. https://doi.org/10.1061/(ASCE)WR.1943-5452.0000974S04018055-104018055-12144

Management of uncertain pairwise comparisons in AHP through probabilistic concepts

[EN] Fast and judicious decision-making is paramount for the success of many activities and processes. However, various degrees of difficulty may affect the achievement of effective and optimal solutions. Decisions should ideally meet the best trade-off among as many of the involved factors as possible, especially in the case of complex problems. Substantial cognitive and technical skills are indispensable, while not always sufficient, to carry out optimal evaluations. One of the most common causes of wrong decisions derives from uncertainty and vagueness in making forecasts or attributing judgments. The literature shows numerous efforts towards the optimization and modeling of uncertain contexts by means of probabilistic approaches. This paper proposes the use of probability theory to estimate uncertain expert judgments within the framework of the analytic hierarchy process and, more specifically, within a linearization scheme developed by the authors. After describing the necessary probabilistic concepts of interest, the main results are developed. These results can be summarized as using various kinds of random variables with uncertainty embodied in undecided pairwise comparisons. A case study focused on the maintenance management of an industrial water distribution system exemplifies the approach.Benítez López, J.; Carpitella, S.; Certa, A.; Izquierdo Sebastián, J. (2019). Management of uncertain pairwise comparisons in AHP through probabilistic concepts. Applied Soft Computing. 78:274-285. https://doi.org/10.1016/j.asoc.2019.02.020S2742857

Hybrid SOM+k-Means Clustering to Improve Planning, Operation and Management in Water Distribution Systems

[EN] With the advance of new technologies and emergence of the concept of the smart city, there has been a dramatic increase in available information. Water distribution systems (WDSs) in which databases can be updated every few minutes are no exception. Suitable techniques to evaluate available information and produce optimized responses are necessary for planning, operation, and management. This can help identify critical characteristics, such as leakage patterns, pipes to be replaced, and other features. This paper presents a clustering method based on self-organizing maps coupled with k-means algorithms to achieve groups that can be easily labeled and used for WDS decision-making. Three case-studies are presented, namely a classification of Brazilian cities in terms of their water utilities; district metered area creation to improve pressure control; and transient pressure signal analysis to identify burst pipes. In the three cases, this hybrid technique produces excellent results. © 2018 Elsevier Ltd. All rights reserved.This work is partially supported by Capes and CNPq, Brazilian research agencies. The use of English was revised by John Rawlins.Brentan, BM.; Meirelles, G.; Luvizotto, E.; Izquierdo Sebastián, J. (2018). Hybrid SOM+k-Means Clustering to Improve Planning, Operation and Management in Water Distribution Systems. Environmental Modelling & Software. 106:77-88. https://doi.org/10.1016/j.envsoft.2018.02.013S778810

Cómo tomar una decisión. Analytic Hierarchy Process: otro uso de las matrices

[ES] Este artículo explica la teoría del Analytic Hierarchy Process, una herramienta matemática destinada a la detección de una jerarquía global en un conjunto sobre cuyos elementos se conocen relaciones de prioridad dos a dos. La herramienta fundamental usada es el Álgebra Matricial, lo que puede resultar útil para ser presentado como ejemplo de uso práctico del Álgebra Lineal.Benítez López, J.; Izquierdo Sebastián, J. (2019). Cómo tomar una decisión. Analytic Hierarchy Process: otro uso de las matrices. La Gaceta de la Real Sociedad Matemática Española. 22(1):61-79. http://hdl.handle.net/10251/139842S617922

Advanced Hydroinformatic Techniques for the Simulation and Analysis of Water Supply and Distribution Systems

[EN] This document is intended to be a presentation of the Special Issue "Advanced Hydroinformatic Techniques for the Simulation and Analysis of Water Supply and Distribution Systems". The final aim of this Special Issue is to propose a suitable framework supporting insightful hydraulic mechanisms to aid the decision-making processes of water utility managers and practitioners. Its 18 peer-reviewed articles present as varied topics as: water distribution system design, optimization of network performance assessment, monitoring and diagnosis of pressure pipe systems, optimal water quality management, and modelling and forecasting water demand. Overall, these articles explore new research avenues on urban hydraulics and hydroinformatics, showing to be of great value for both Academia and those water utility stakeholders.Herrera Fernández, AM.; Meniconi, S.; Alvisi, S.; Izquierdo Sebastián, J. (2018). Advanced Hydroinformatic Techniques for the Simulation and Analysis of Water Supply and Distribution Systems. Water. 10(4):1-7. https://doi.org/10.3390/w10040440S1710