Ponencias (Matemática Aplicada I)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10896

Examinar

Mostrando 1 - 20 de 241

A depth-averaged grain-fluid model with dilatancy and an upper-solid layer
(EDP Sciences, 2025) Bouchut, François; Fernández Nieto, Enrique Domingo; Mangeney, Anne; Narbona Reina, Gladys; Matemática Aplicada I; Ministerio de Ciencia e Innovación (MICIN). España; FQM120: Modelado Matemático y Simulación de Sistemas Medioambientales
To effectively assess the growing hazard related to debris flows, it is crucial to simulate these natural grain-fluid flows at a reasonable computational cost. To complement existing depth-averaged grain-fluid flow models with an upper-fluid layer, we propose here a model with an upper-solid layer, as a first step towards the development of unified models describing all possible configurations. This model accounts for granular mass dilatancy and pore fluid pressure feedback and solves for solid and fluid velocity in the mixture and for the upper-solid velocity. Simulation in uniform configurations reveals the rich behaviour of the flow and shows that the upper-solid and upper-fluid models may predict very different behaviour. Our work highlights the need of developing two-layer models accounting for dilatancy and unifying upper-solid and upper-fluid configurations in the same framework.
Almost Bent functions for Hadamard matrices and APN functions
(Universidad de León, 2025) Armario Sampalo, José Andrés; Matemática Aplicada I; Ministerio de Ciencia e Innovación (MICIN). España; FQM016: Códigos, Diseños, Criptografía y Optimización
It is well-known that bent sequences are linked to Sylvester Hadamard matrices. Recently, the notion of bent sequence has been extended to other kinds of Hadamard matrices. The aim of this paper is not only to review some progresses on bent sequences for Hadamard matrices, but also to suggest an analogo us approach for Almost Bent functions.The notion of Almost Bent function attached to a Hadamard matrix is introduced and two open questions in connection with Almost Perfect Nonlinear functions are formulated.
Un esquema de autenticación gráfica basado en cuadrados latinos
(Universidad de León, 2025) Falcón, Raúl M.; Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau, Dolores M.; González Regadera, Manuel; Gudiel, Félix; Güemes, Belén M; Matemática Aplicada I; Ministerio de Ciencia e Innovación (MICIN). España; FQM016: Códigos, Diseños, Criptografía y Optimización
En contraposición a las contraseñas alfanuméricas, los esquemas de autenticación gráfica presentan un entorno amigable más satisfactorio para el usuario, disponen de un mayor espacio de claves y mayor resistencia a ataques criptográficos. Este trabajo (presentado previamente en las IX Jornadas Nacionales de Investigación en Ciberseguridad [1]) plantea un nuevo diseño de esquemas de autenticación gráfica basados en el uso de cuadrados latinos y el denominado producto Hadamard para cuasigrupos, recientemente introducido por los autores.
Use of LiDAR Maps for the Analysis of Differential Movements in Buildings
(Springer Nature, 2026) Cano-Marín, Rubén; Delgado Sánchez, Juan Manuel; Estructuras de Edificación e Ingeniería del Terreno; Matemática Aplicada I
The Spanish National Plan for Aerial Orthophotography (PNOA) has implemented the PNOA-LiDAR project, aimed at capturing three-dimensional information of the Spanish territory using airborne LiDAR (Light Detection and Ranging) sensors. Through this optical remote sensing technique, the second LiDAR flight coverage has achieved a resolution of up to 4 points per square metre and a root mean square error (RMSE) in altimetric measurement of less than 20 cm. This level of precision could enable the analysis of elevations and differential settlements in buildings associated with foundation failures or changes in ground conditions, provided that they exceed the LiDAR margin of error. This communication presents a case study of a house that, after its construction, experienced differential settlements greater than 20 cm, measured by topographic levelling on site, which were compared with measurements obtained from the LiDAR point cloud. The results obtained from the point cloud of the second PNOA-LiDAR coverage show acceptable deviations compared to the on-site measurements, providing valid information on the trend, direction, sense, and approximate magnitude of the differential movement. These findings confirm the potential of PNOA-LiDAR for the study of damage in buildings and civil engineering works associated with ground movements, as well as its application in this type of study on an urban scale.
Additive partial matchings for persistent homology
(ACM, 2025-07-28) González Díaz, Rocío; Soriano Trigueros, Manuel; Torras Casas, Álvaro; Matemática Aplicada I; French Agence Nationale de la Recherche
Persistence modules (defined as a sequence of vector spaces and linear maps between them) are a key tool in topological data analysis. They are easy to interpret and fast to compute. However, when considering persistence maps (i.e. maps between persistence modules), these properties are lost. We propose a new invariant for persistence maps consisting of a partial matching such that: it is easy to interpret, it is more discriminative than the image of the persistence map, and can be calculated with cubical complexity
Algorithms for distance problems in continuous graphs
(Schloss Dagstuhl: Leibniz-Zentrum fuer Informatik, 2025) Cabello Justo, Sergio; Garijo Royo, Delia; Kalb, Antonia; Klute, Fabian; De Parada Muñoz, Irene María; Silveira Isoba, Rodrigo Ignacio; Matemática Aplicada I; FQM164: Matemática Discreta: Teoría de Grafos y Geometría Computacional
We study the problem of computing the diameter and the mean distance of a continuous graph, i.e., a connected graph where all points along the edges, instead of only the vertices, must be taken into account. It is known that for continuous graphs with m edges these values can be computed in roughly O(m²) time. In this paper, we use geometric techniques to obtain subquadratic time algorithms to compute the diameter and the mean distance of a continuous graph for two well-established classes of sparse graphs. We show that the diameter and the mean distance of a continuous graph of treewidth at most k can be computed in O(n log^O(k) n) time, where n is the number of vertices in the graph. We also show that computing the diameter and mean distance of a continuous planar graph with n vertices and F faces takes O(n F log n) time.
Diseño y validación de rúbricas estandarizadas para la evaluación de Trabajos Fin de Grado experimentales
(REDINE (Red de Investigación e Innovación Educativa), 2025) Valera Córdoba, María Mercedes; Sánchez Guerrero, María José; Castro Valdecantos, Pedro; Pérez Urrestarazu, Luis; Florido Fernández, María del Carmen; Moreno González, Auxiliadora; Bartolomé Medina, Ester; Matemática Aplicada I; Agronomía; Ingeniería Aeroespacial y Mecánica de Fluidos; Cristalografía, Mineralogía y Química Agrícola; Proyecto de Innovación Docente
This paper analyzes the design, implementation, and evaluation of a rubric for grading Final Degree Projects (FDPs) in the experimental format of the Agricultural Engineering Degree at the University of Seville. Two versions were compared: an initial, more detailed and extensive version (PRE), and a simplified version (SRE), redesigned based on the evaluator’s feedback. The results show that the SRE received higher ratings from the examining board members, who considered it more useful, clear, and easy to apply, although its correlation with the final grade was slightly lower than the original version. The study concludes that a clear, simple rubric with differentiated weighting and well-defined criteria favors objectivity and evaluator acceptance, provided that a balance with accuracy in assessing complex competencies is maintained with accuracy in the assessment of complex competencies.
On HL2 (L, L) for semisimple Leibniz algebras
(IOP Publishing, 2016) Camacho Santana, Luisa María; Ladra, M.; Turdibaev, R. M.; Matemática Aplicada I
In this paper we present a decomposition of HLn(L;L) into a direct sum of some subspaces for a finite dimensional complex semisimple Leibniz algebra L: Furthermore, we provide a more specific decomposition in case n = 2 into two subspaces. We verify that one of those subspaces annihilates for specific Leibniz algebras with liezation sl2 and some others.
Topological Data Analysis for Self-organization of Biological Tissues
(Springer, 2017) Jiménez Rodríguez, María José; Rucco, Matteo; Vicente Munuera, Pablo; Gómez Gálvez, Pedro; Escudero Cuadrado, Luis María; Matemática Aplicada I; Ministerio de Economía y Competitividad (MINECO). España; Programa Ramón y Cajal; Fundación Asociación Española contra el cáncer; Universidad de Sevilla
In this paper we propose a method to topologically analyze segmented images of cells in a biological tissue. This is a mainly exper- imental paper in which we present initial results of applying persistent homology computation to characterize cell organization. For that aim, a graph is constructed to model the cell organization and a simplicial complex is derived from such a graph. Then a filter function is designed, on the simplicial complex, that reflects neighbouring relations on cells as well as their size. Finally, persistent homology and persistent entropy are computed and the results are analyzed.
Topological Analysis of Simple Segmentation Maps
(Springer, 2022) Jiménez Rodríguez, María José; Medrano Garfia, Belén; Matemática Aplicada I; Ministerio de Ciencia e Innovación; Agencia Estatal de Investigación. España; Agencia Andaluza del Conocimiento
In this paper, we propose a geometry-aware topological anal- ysis of a segmentation of an image into regions which might correspond, for example, to a geographical map or to segmented cells in a micro- scopic image of a biological packed tissue. The regions must satisfy that the centroid of each one lies inside the region itself. We propose a novel simplicial complex modeling such data, for persistent homology compu- tation, that better respects the geometry of the regions than existing techniques. More specifically, our approach joins benefits from previous models by encoding both neighbouring relations between the regions, as well as spatial distribution of the set of centroids. In addition, we intro- duce geometric information regarding distances between centroids and boundaries delimiting each region.
On topological analysis of cells organization in biological images
(Springer, 2021-05-16) Jiménez Rodríguez, María José; Matemática Aplicada I; Ministerio de Ciencia e Innovación
There are many problems inside the field of biomedical image analysis that can be dealt from a topological (and geometric) point of view. One of them refers to the way in which cells are self-organised inside a tissue, mainly motivated by the changes that may occur in such an organization in case of disease. This problem can be faced from differ ent perspectives in terms, first, of how to model the cells and their ‘con nections’ and second, how to computationally characterise their organi zation. We will discuss some topological approaches to this topic as well as future lines of research.
On the Computation of A∞-Maps
(Springer, 2007) Berciano, Ainhoa; Jiménez Rodríguez, María José; Real Jurado, Pedro; Matemática Aplicada I
Starting from a chain contraction (a special chain homotopy equivalence) connecting a differential graded algebra A with a differen tial graded module M, the so-called homological perturbation technique “tensor trick” [8] provides a family of maps, {mi}i≥1, describing an A∞- algebra structure on M derived from the one of algebra on A. In this paper, taking advantage of some annihilation properties of the compo nent morphisms of the chain contraction, we obtain a simplified version of the existing formulas of the mentioned A∞-maps, reducing the com putational cost of computing mn from O(n! 2) to O(n!).
Finding Multiple Solutions in Nonlinear Integer Programming with Algebraic Test-Sets
(Springer, 2018-08-23) Hartillo Hermoso, Isabel; Jiménez Cobano, José Manuel; Ucha Enríquez, José María; Matemática Aplicada I
We explain how to compute all the solutions of a nonlinear integer problem using the algebraic test-sets associated to a suitable linear subproblem. These test-sets are obtained using Gr¨obner bases. The main advantage of this method, compared to other available alternatives, is its exactness within a quite good efficiency.
Numerical Simulation of an Induction-Conduction Model Arising in Steel Hardening
(Int Assoc. Engineers-Iaeng NT, 2009) Díaz Moreno, J.M.; García Vazquez, C.; González Montesinos, María Teresa; Ortegón Gallego, F.; Matemática Aplicada I
We study a mathematical model for the description of the heating-cooling industrial process of a steel workpiece. The complete thermomechanical model is governed by a nonlinear coupled partial differential system of equations involving the electric potential, the magnetic vector potential, the temperature, the stress tensor and the displacement field together with a system of ordinary differential equations for the steel phase fractions. In this situation, the electric conductivity on the workpiece depends strongly on the temperature b = b(x, theta), theta being the temperature. Usually one has b(x, s) -> 0 when s -> infinity uniformly on the workpiece, leading to degenerate parabolic/elliptic equations. Our analysis considers the case 0 < C-1/(1 + vertical bar s vertical bar) b(x, s) C-2, C-1 and C-2 being constant values. Also we have performed some 2D numerical simulations of the heating-cooling process in a simplified version of the model.
Numerical Simulation of Potential Maxwell's Equations in the Harmonic Regime
(Springer Nature, 2015) González Montesinos, María Teresa; Ortegón Gallego, Francisco; Matemática Aplicada I
The aim of this work is to perform some numerical experiments for the resolution of a strongly coupled parabolic–elliptic system that describes the heating induction–conduction industrial process of a steel workpiece, whose unknowns are the electric potential, the magnetic vector potential, and the temperature. In order to make the numerical simulations lighter, and taking into account the different time scales between the potentials and the temperature, a new system of nonlinear partial differential equations (PDEs) has been constructed that describes the heating process in the harmonic regime.
Desarrollo de una práctica de eficiencia energética en Arquitectura mediante simulación numérica
(REDINE, Red de Investigación e Innovación Educativa, 2021) Domínguez Torres, Carlos Antonio; Domínguez Delgado, Antonio; Matemática Aplicada I; Estructuras de Edificación e Ingeniería del Terreno
En este trabajo se presenta el desarrollo de una práctica de eficiencia energética en Arquitectura efectuada mediante técnicas de simulación numérica. El objetivo de la práctica es doble: por un lado concienciar al alumnado de la necesidad de implementar medidas de eficiencia energética conducentes a reducir el consumo energético necesario para conseguir condiciones de habilitad adecuadas en las viviendas y por otro lado, introducir al alumnado en el manejo de técnicas de simulación numérica cada día más usadas en el ámbito técnico, y específicamente en Arquitectura, tanto en la fase de diseño previo de un proyecto arquitectónico nuevo como de la implementación de medidas de rehabilitación sobre viviendas ya construidas, con el objetivo de reducir el consumo energético de los edificios y por ende, contribuir a la reducción de la pobreza energética y del impacto ambiental y climático del consumo de energía en el parque de viviendas.
El tamaño de un grafo con cintura inferiormente acotada
(Servicio de Publicaciones de la Universidad de Cádiz, 2007) Abajo Casado, María Encarnación; Diánez Martínez, Ana Rosa; Matemática Aplicada I
Automorphisms, derivations and gradings of the split quartic Cayley algebra
(Springer, 2023) Blasco Jiménez, Víctor; Daza García, Alberto; Matemática Aplicada I; Agencia Estatal de Investigación. España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
The split quartic Cayley algebra is a structurable algebra which has been used to give constructions of Lie algebras of type D4. Here, we calculate it’s group of automorphisms, it’s algebra of derivations and it’s gradings.
Measuring the error of linear separators on linearly inseparable data
(Prensas Universitarias de Zaragoza, 2009-06) Aronov, Boris; Garijo Royo, Delia; Núñez Rodríguez, Yurai; Rappaport, David; Seara Ojea, Carlos; Urrutia, Jorge; Matemática Aplicada I; Ministerio de Educación y Ciencia (MEC). España; Junta de Andalucía
Given linearly inseparable sets R of red points and B of blue points, we consider several measures of how far they are from being separable. Intuitively, given a potential separator ("classifier"), we measure its quality ("error") according to how much work it would take to move the misclassified points across the classifier to yield separated sets. We consider several measures of work and provide algorithms to find linear classifiers that minimize the error under these diferent measures.
Breaking symmetries of graphs with resolving sets
(2014) Garijo Royo, Delia; González Herrera, Antonio; Márquez Pérez, Alberto; Matemática Aplicada I; Junta de Andalucía; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
We undertake a study on the maximum value of the difference between the metric dimension and the determining number of a graph as a function of its order. Our results include lower and upper bounds on that maximum, and exact computations when restricting to some specific families of graphs. Although our technique is mainly based on locating-dominating sets, it also requires very diverse tools and relationships with well-known objects in graph theory; among them: a classical result in graph domination by Ore, a Ramsey-type result by ErdHos and Szekeres, a polynomial time algorithm to compute distinguishing sets and dominating sets of twin-free graphs, k-dominating sets, and matchings.

Examinar

Envíos recientes