Now showing items 1-10 of 10

  • A meta-analysis on classification model performance in real-world datasets: an exploratory view 

    Gómez Guillen, David; Rojas Espinosa, Alfonso (2018-02-22)
    Article
    Restricted access - publisher's policy
    The No Free Lunch (NFL) Theorem imposes a theoretical restriction on optimization algorithms and their equal average performance on different problems, under some particular assumptions. Nevertheless, when brought into ...
  • Análisis del protocolo IEEE 802.11b en un entorno celular 

    López Aguilera, M. Elena; Casademont Serra, Jordi; Rojas Espinosa, Alfonso (Universidad de Las Palmas de Gran Canaria, Servicio de Publicaciones, 2003)
    Conference report
    Open Access
    In this paper we present an analysis of the protocol IEEE 802.11b in different environments. Its performance in an indoor environment is evaluated, in terms of throughput and transmission delay, and the influence of the ...
  • An empirical overview of the No Free Lunch Theorem and its effect on Real-World Machine Learning Classification 

    Gomez Guillen, David; Rojas Espinosa, Alfonso (2016-01-01)
    Article
    Open Access
    A sizable amount of research has been done to improve the mechanisms for knowledge extraction such as machine learning classification or regression. Quite unintuitively, the no free lunch (NFL) theorem states that all ...
  • Enhancement proposal for WLAN IEEE 802.11e: desynchronization of its working procedure 

    López Aguilera, M. Elena; Casademont Serra, Jordi; Cotrina Navau, Josep; Rojas Espinosa, Alfonso (Institute of Electrical and Electronics Engineers, 2005)
    Conference report
    Open Access
    Up to the present, several studies have been performed in order to provide prioritization of stations or classes of service for WLAN IEEE 802.11. The IEEE 802.11e draft specification aims to extend the original IEEE 802.11 ...
  • Examen Final 

    Barba Martí, Antonio; Remondo Bueno, David; Rojas Espinosa, Alfonso (Universitat Politècnica de Catalunya, 2013-06-19)
    Exam
    Restricted access to the UPC academic community
  • MALLBA: a library of skeletons for combinatorial optimisation 

    Alba, E; Almeida, F; Blesa Aguilera, Maria Josep; Cabeza, J; Cotta, C; Díaz, M; Dorta, I; Gabarró Vallès, Joaquim; León, C; Luna Garcia, Jesus; Moreno Boronat, Lidia Ana; Pablos, C; Petit Silvestre, Jordi; Rojas Espinosa, Alfonso; Xhafa Xhafa, Fatos (2002-02)
    External research report
    Open Access
    The MALLBA project tackles the resolution of combinatorial optimization problems using algorithmic skeletons implemented in C++. MALLBA offers three families of generic resolution methods: exact, heuristic and hybrid. ...
  • Performance enhancement of outdoor IEEE 802.11 cellular networks 

    López Aguilera, M. Elena; Casademont Serra, Jordi; Rojas Espinosa, Alfonso; Cotrina Navau, Josep (ACTA Press, 2005-07)
    Conference report
    Open Access
    Most studies about the performance of IEEE 802.11 are limited to a single cell environment. Nevertheless, the idea of designing an outdoor cellular network based on WLAN IEEE 802.11 results very attractive, due to the ...
  • Performance enhancement of WLAN IEEE 802.11 for asymmetric traffic 

    López Aguilera, M. Elena; Casademont Serra, Jordi; Cotrina Navau, Josep; Rojas Espinosa, Alfonso (Institute of Electrical and Electronics Engineers, 2005)
    Conference report
    Open Access
    Most studies about the performance of IEEE 802.11 consider scenarios of ad-hoc topology and networks where all stations have the same traffic load (symmetric traffic conditions). This paper presents a study of performance ...
  • Simulation of cell signalling communications using event-driven algorithms 

    Huertas Gonzalez, Daniel; Rojas Espinosa, Alfonso (2014)
    Conference report
    Open Access
    In this paper we present two implementations of event-driven algorithms for simulating molecular dynamics using the Omnet++ Simulation Framework and its Future Event Set (FES) implementation. The first one uses a cell-linked ...
  • Wireless technology applied to GIS 

    Casademont Serra, Jordi; López Aguilera, M. Elena; Paradells Aspas, Josep; Rojas Espinosa, Alfonso; Calveras Augé, Anna M.; Barceló Arroyo, Francisco; Cotrina Navau, Josep (Elsevier, 2004-07)
    Article
    Restricted access - publisher's policy
    At present, there is a growing interest in wireless applications, due to the fact that the technology begins to support them at reasonable costs. In this paper, we present the technology currently available for use in ...