Recursos de colección

Archivo Digital UPM (107.543 recursos)

This is an institutional repository providing access to the research output of the institution. Primarily contains thesis.

Materia = Matemáticas

Mostrando recursos 1 - 20 de 1.208

  1. Non-cooperative target identification based on singular value decomposition

    Hernán Vega, Olga; López Rodríguez, Patricia; Escot Bocanegra, David; Fernández Recio, Raúl; Bravo Muñoz, Ignacio
    Non-Cooperative Target Identification based on High Resolution Range Profiles is a key research domain in the Defense industry. In this paper a method based on the application of Singular Value Decomposition to a matrix of range profiles is defined. The decomposition is applied to reduce dimensionality and to accomplish recognition in the transformed domain. So as to confirm the feasibility of the methodology, identification experiments of profiles coming from electromagnetic simulations are conducted, revealing promising results.

  2. Non-cooperative identification of civil aircraft using a generalised mutual subspace method

    López Rodríguez, Patricia; Escot Bocanegra, David; Fernández Recio, Raúl; Bravo Muñoz, Ignacio
    The subspace-based methods are effectively applied to classify sets of feature vectors by modelling them as subspaces. However, their application to the field of non-cooperative target identification of flying aircraft is barely seen in the literature. In these methods, setting the subspace dimensionality is always an issue. Here, it is demonstrated that a modified mutual subspace method, which uses softweights to set the importance of each subspace basis, is a promising classifier for identifying sets of range profiles coming from real in-flight targets with no need to set the subspace dimensionality in advance. The assembly of a recognition database is also...

  3. Diseño de un regulador no lineal por bloques para el sistema glucosa-insulina utilizando redes neuronales de alto orden

    Orozco López, Onofré; Rodríguez Herrero, Agustín; Castañeda Hernández, Carlos Eduardo; García Sáez, Gema; Hernando Pérez, María Elena
    En este trabajo se propone un algoritmo de control en lazo cerrado para el control automático de la diabetes tipo 1 basado en la identificación de sistemas no lineales con redes neuronales artificiales y mediante la regulación basada en la forma controlable no lineal por bloques. Como paciente virtual se utiliza el modelo de Hovorka al que se conecta el algoritmo de control utilizando prealimentación procedente de la terapia prescrita con insulina y un módulo de seguridad para evitar las hipoglucemias. El identificador neuronal es entrenado en línea con un filtro de Kalman extendido con una función de activación definida...

  4. An inverse problema for the compressible Reynolds equation

    Dager Salomon, Rene; Negreanu, Mihaela; Tello del Castillo, Jose Ignacio
    We study the existence of solutions to a system of equations for equilibrium positions in lubricated journal bearings under load effects. The mechanism under consideration consists of two parallel cylinders, one inside the other, in close distance and relative motion. The unknowns of the problem are the equilibrium position of the inner cylinder and the pressure of the lubricant described by the compressible Reynolds equation. To complete the system, Newton's second law gives the equilibrium of forces. We present results on existence of solutions for a range of applied forces F.

  5. Monocular visual-inertial SLAM-based collision avoidance strategy for fail-safe UAV using fuzzy logic controllers

    Fu, Changhong; Olivares Mendez, Miguel Ángel; Suarez Fernandez, Ramon; Campoy Cervera, Pascual
    In this paper, we developed a novel Cross-Entropy Optimization (CEO)-based Fuzzy Logic Controller (FLC) for Fail-Safe UAV to expand its collision avoidance capabilities in the GPS-denied envrionments using Monocular Visual-Inertial SLAM-based strategy. The function of this FLC aims to control the heading of Fail-Safe UAV to avoid the obstacle, e.g. wall, bridge, tree line et al, using its real-time and accurate localization information. In the Matlab Simulink-based training framework, the Scaling Factor (SF) is adjusted according to the collision avoidance task firstly, and then the Membership Function (MF) is tuned based on the optimized Scaling Factor to further improve the...

  6. An inverse problema for the compressible Reynolds equation

    Dager Salomon, Rene; Negreanu, Mihaela; Tello del Castillo, Jose Ignacio
    We study the existence of solutions to a system of equations for equilibrium positions in lubricated journal bearings under load effects. The mechanism under consideration consists of two parallel cylinders, one inside the other, in close distance and relative motion. The unknowns of the problem are the equilibrium position of the inner cylinder and the pressure of the lubricant described by the compressible Reynolds equation. To complete the system, Newton?s second law gives the equilibrium of forces. We present results on existence of solutions for a range of applied forces F.

  7. APLICA_MATES: Una comunidad virtual de aprendizaje

    García López, Alfonsa; García Mazarío, Francisco; Pinero Fernández, Rosa María; Rubio, Miguel Ángel
    En este trabajo se presenta la experiencia de la creación de APLICA_MATES, comunidad virtual de aprendizaje creada por el grupo de innovación educativa GIEMATIC de la Universidad Politécnica de Madrid, como parte de su estrategia de incorporación de tecnología en las actividades de aprendizaje y evaluación. Se trata de una comunidad privada, formada por profesores y estudiantes, que pretende facilitar la integración social y académica de los alumnos de primer curso, mediante actividades de aprendizaje colaborativo, compartiendo recursos y noticias de divulgación matemática.

  8. On the existence of time lags between changes in real estate prices and explanatory macroeconomic variables. A regression analysis applied to the city of Stockholm

    Söderberg, Bo; Samartín, Avelino; Andersson, Roland
    The prices of real estate in a region change over time in response to changes in several economic background variables, such as population, income,unemployment rate, interest rate etc. In this paper a multiple regression analysis between real estate prices and some economic background variables will be described. This regression analysis will be applied to data for residential real estate transactions that took place in the city of Stockholm during the period 1985-1994. From this regression analysis the set of background variables that presents the strongest explanation of the variations will be identified. If a lag dependence between these background variables with the...

  9. Numerical simulation of a climate model with latent heat of fusion

    Hidalgo López, Arturo
    Physical problem. Mathematical model. Numerical approximation. Numerical examples. Conclusions and further research.

  10. Métodos ADER-WENO en volúmenes finitos aplicados a la resolución de problemas hiperbólicos en mallados con refinamiento adaptativo.

    Hidalgo López, Arturo
    Motivation. Mathematical formulation. WENO reconstruction. Local-Space time DG. Adaptive Mesh Refinement. Numerical examples

  11. Numerical simulation of a climate energy balance model with continents distribution

    Hidalgo López, Arturo; Tello Castillo, Lourdes
    Numerical simulation of a climate energy balance model with continents distribution

  12. ADER-WENO Finite volume schemes with adaptive mesh refinement for hyperbolic problems

    Hidalgo López, Arturo
    In this work it is presented an ADER-WENO approach for hyperbolic problems in the context of the finite volume method, using adaptive mesh refinement. ADER approach is of great interest for time integration since it achieves an arbitrary order of accuracyin a single time step. This is a joint work with M. Dumbser and O. Zanotti from the University of Trento (Italy).

  13. An ADER finite volume method for an atherosclerosis model

    Hidalgo Lopez, Arturo; Tello Castillo, Lourdes
    Biological motivation. Mathematical model. Numerical approximation. Convergence test for auxiliary reaction- diffusion problem. Numerical examples. Characterization of initial conditions in the phase plane. 2D Cas. Conclusions and further research.

  14. Mathematical modeling and numerical simulation of two-phase flow problems at pore scale

    Hidalgo López, Arturo; Luna Dapica, Paula
    Simulación numérica de flujo bifásico en medio poroso mediante un método de elementos finitos para la resolución de la presión y un método de volúmenes finitos para la resolución de la saturación. Los resultados numéricos se comparan con los obtenidos con el código comercial ECLIPSE.Mathematical modeling and numerical simulation of two-phase flow through porous media is a very active field of research, because of its relevancy in a wide range of physical and technological applications. Some outstanding applications concern reservoir simulation and oil and gas recovery, fields in which a great effort is being paid in the development of efficient...

  15. Demography-based adaptive network model reproduces the spatial organization of human linguistic groups

    Capitán Gómez, José Ángel; Manrubia, Susanna
    The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully...

  16. The spaces of analytic functions on open subsets of RN and CN

    Martínez Ansemil, José M.; López Salazar, Jerónimo; Ponte Miramontes, Socorro
    This paper is devoted to study the space A(U) of all analytic functions on an open subset U of RN or CN. It is proved that if U satisfies a weak condition (that will be called 0-property), then every f∈A(U) depends only on a finite number of variables. Then several topologies on A(U) are studied: the compact open topology, the τδ topology (already known in spaces of holomorphic functions) and a new one, defined by the inductive limit of the subspaces of analytic functions which only depend on the first variables.

  17. Dynamical community structure of populations evolving on genotype networks

    Capitán Gómez, José Ángel; Aguirre, Jacobo; Manrubia, Susanna
    Neutral evolutionary dynamics of replicators occurs on large and heterogeneous networks of genotypes. These networks, formed by all genotypes that yield the same phenotype, have a complex architecture that conditions the molecular composition of populations and their movements on genome spaces. Here we consider as an example the case of populations evolving on RNA secondary structure neutral networks and study the community structure of the network revealed through dynamical properties of the population at equilibrium and during adaptive transients. We unveil a rich hierarchical community structure that, eventually, can be traced back to the non-trivial relationship between RNA secondary structure...

  18. Predicting recurring concepts on data-streams by me ans of a meta-model and a fuzzy similarity function

    Abad Arranz, Miguel Ángel; Gomes, João Bartolo; Menasalvas Ruiz, Ernestina
    Meta-models can be used in the process of enhancing the drift detection mechanisms used by data stream algorithms, by representing and predicting when the change will occur. There are some real-world situations where a concept reappears, as in the case of intrusion detection systems(IDS), where the same incidents or an adaptation of them usually reappear over time. In these environments the early prediction of drift by means of a better knowledge of past models can help to anticipate to the change, thus improving efficiency of the model regarding the training instances needed. In this paper we present MM-PRec, a meta-model...

  19. Antecedentes, lagunas y nuevos resultados en los conjuntos borrosos de tipo 2

    Hernández Varela, Pablo Ramón; Cubillo Villanueva, Susana; Torres Blanc, Carmen
    A partir del “Principio de Extensión” de Zadeh se han generalizado a los conjuntos borrosos de tipo 2 (T2FSs), definiciones, operaciones, propiedades y resultados obtenidos en los conjuntos borrosos (FSs). Sin embargo, como sucede en cualquier área de investigación, quedan muchas lagunas y problemas abiertos que suponen un reto para cualquiera que quiera hacer un estudio profundo en este campo. A este reto nos hemos enfrentado los autores del presente artículo, que pretende ser una exposición de algunos de los avances realizados en este sentido de "rellenar huecos" existentes en la teoría de conjuntos de tipo 2. En particular, se abordarán las negaciones que permiten hablar de la propiedad de autocontradicción, las t-normas y tconormas.

  20. Affective Mapping of Social Networks.

    Wachowicz, Monica; Iturrioz Aguirre, Teresa; Cano, Jorge; Polonia, Amelia; Pinto, Sara
    Very little is know about how the patterns of collective experiences towards a Place can quantitatively as well as qualitatively be represented based on subjective data. Therefore, our research challenge is two-fold: (a) to define what Place is by pointing to ways in which emotion states can be observed and are bound together within a social network; and (b) to develop a visual representation that provides the framework for representing patterns of emotion states associated to this Place. Towards this end, this paper will demonstrate our first results on the analysis of the correspondence obtained in the archive of Simón...

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