Ara es mostren els items 1-20 de 25

    • Análisis de datos composicionales: aguas, contaminantes, recursos, sociología... 

      Egozcue Rubí, Juan José; Tolosana Delgado, Raimon; Jarauta Bragulat, Eusebio; Ortego Martínez, María Isabel; Díaz Barrero, José Luis (Universitat Politècnica de Catalunya. Escola Tècnica Superior d'Enginyers de Camins Canals i Ports de Barcelona, 2011-11-15)
      Comunicació de congrés
      Accés obert
      Los datos composicionales describen las partes de un todo. Se presentan en forma de vectores proporciones, porcentajes, concentraciones químicas etc. y aparecen en multitud de campos de la ciencia y la ingeniería. A pesar ...
    • Análisis y previsión de fenómenos naturales peligrosos 

      Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Ortego Martínez, María Isabel; Sánchez-Arcilla Conejo, Agustín (Universitat Politècnica de Catalunya. Escola Tècnica Superior d'Enginyers de Camins Canals i Ports de Barcelona, 2011-11-16)
      Comunicació de congrés
      Accés obert
      La toma de decisiones referentes al diseño o en sistemas de alerta requieren el estudio de las acciones externas (frecuentemente meteorológicas), la descripción probabilista del sistema (vulnerabilidad, susceptibilidad) ...
    • Bayesian trend analysis for daily rainfall series of Barcelona 

      Ortego Martínez, María Isabel; Gibergans Bàguena, José; Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Llasat Botija, Maria Carmen (2010-07-15)
      Article
      Accés obert
      A Point-Over-Threshold approach using a reparameterization of the Generalized Pareto Distribution (GPD) has been used to assess changes in the daily rainfall Barcelona series (1854–2006). A Bayesian approach, considering ...
    • Checking model-data weather hazard occurrence fit in the context of climate change 

      Tolosana Delgado, Raimon; Ortego Martínez, María Isabel; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín (2011)
      Text en actes de congrés
      Accés obert
      In climate change impact studies it is common to run a given response model (from ecosystem changes to wavestorm or landslide occurrence) nested into one of the available long-term Global or Regional Circulation Models ...
    • Classifying wave forecasts with model-based geostatistics and the Aitchison distribution 

      Tolosana Delgado, Raimon; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín; Gómez Aguar, Jesús Javier (2010)
      Text en actes de congrés
      Accés restringit per política de l'editorial
    • Climate change in a Point-Over-Threshold model: an example on ocean-wave-storm hazard in NE Spain 

      Tolosana Delgado, Raimon; Ortego Martínez, María Isabel; Egozcue Rubí, Juan José; Sánchez-Arcilla Conejo, Agustín (2010-09-27)
      Article
      Accés obert
      A reparametrization of the Generalized Pareto Distribution is here proposed. It is suitable to parsimoniously check trend assumptions within a Point-Over-Threshold model of hazardous events. This is based on considerations ...
    • Combining isotopic and compositional data: a discrimination of regions prone to nitrate pollution 

      Puig, Roger; Tolosana Delgado, Raimon; Otero, Neus; Folch Sancho, Albert (John Wiley & Sons, 2011)
      Capítol de llibre
      Accés restringit per política de l'editorial
    • Discrimination of TiO2 polymorphs in sedimentary and metamorphic rocks 

      Triebold, Silke; Luvizotto, George Luiz; Tolosana Delgado, Raimon; Zack, Thomas; von Eynatten, Hilmar (2010-07-13)
      Article
      Accés obert
      Investigation by Raman spectroscopy of samples from different geological settings shows that the occurrence of TiO2 polymorphs other than rutile can hardly be predicted, and furthermore, the occurrence of anatase is more ...
    • Geochemistry versus grain-size relations of sediments in the light of comminution, chemical alteration, and contrasting source rocks 

      von Eynatten, Hilmar; Tolosana Delgado, Raimon (Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE), 2011)
      Text en actes de congrés
      Accés obert
      Around 170 sediment samples from glacial and proximal glacio-fluvial deposits have been analysed for their geochemical composition. Samples derive from two strongly contrasting source areas (granitoids vs. amphibolite) and ...
    • Geochemistry versus grain-size relations of sediments in the light of comminution, chemical alteration, and contrasting source rocks 

      Von Eynatten, H.; Tolosana Delgado, Raimon (CIMNE, 2011)
      Text en actes de congrés
      Accés obert
      Around 170 sediment samples from glacial and proximal glacio-fluvial deposits have been analysed for their geochemical composition. Samples derive from two strongly contrasting source areas (granitoids vs. amphibolite) ...
    • Grain-size control on petrographic composition of sediments: compositional regression and rounded zeroes 

      Tolosana Delgado, Raimon; von Eynatten, Hilmar (2009-03-26)
      Article
      Accés obert
      It is well-known that sediment composition strongly depends on grain size. A number of studies have tried to quantify this relationship focusing on the sand fraction, but only very limited data exists covering wider grain ...
    • Guía para el análisis espacial de datos composicionales 

      Tolosana Delgado, Raimon (2011)
      Article
      Accés obert
      El tratamiento de bases de datos composicionales (proporciones, porcentajes, concentraciones, etc.) con dependencia espacial debe hacerse atendiendo a las características matemáticas de éstos: una composición válida debe ...
    • Jurassic granitoid magmatism in the Dinaride Neotethys: geochronological constraints from detrital minerals 

      Mikes, Tamás; Bäresel, Björn; Kronz, Andreas; Frei, Dirk; Dunkl, István; Tolosana Delgado, Raimon; von Eynatten, Hilmar (2009-12-01)
      Article
      Accés restringit per política de l'editorial
      Three independent single-grain geochronometers applied to detrital minerals from Central Dinaride sediments constrain the timing of felsic magmatism that associated the Jurassic evolution of the Neotethys. The Lower ...
    • Modelling barrier beaches under storms with XBEACH: The case of the Trabucador bar 

      García León, Manuel; Solé, J.M.; Gracia Garcia, Vicente; Alomar, Marta; Tolosana Delgado, Raimon; Fernández, J.; Pallarès López, Elena; Jiménez Quintana, José Antonio; Sánchez-Arcilla Conejo, Agustín (2011)
      Text en actes de congrés
      Accés obert
    • Pluviometric regionalization of Catalunya: a compositional data methodology 

      Gibergans Bàguena, José; Ortego Martínez, María Isabel; Tolosana Delgado, Raimon (Centro Internacional de Métodos Numéricos en Ingeniería (CIMNE), 2011)
      Text en actes de congrés
      Accés obert
      The aim of this paper is to introduce a methodology for de¯ning groups from regionalized com- positional data, through a hierarchical clustering algorithm aware of both the spatial dependence and the compositional character ...
    • Pluviometric regionalization of Catalunya: a compositional data methodology 

      Gibergans Bàguena, José; Ortego Martínez, María Isabel; Tolosana Delgado, Raimon (CIMNE, 2011)
      Text en actes de congrés
      Accés obert
      The aim of this paper is to introduce a methodology for de¯ning groups from regionalized com- positional data, through a hierarchical clustering algorithm aware of both the spatial dependence and the compositional character ...
    • Principal balances 

      Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Tolosana Delgado, Raimon (International Centre for Numerical Methods in Engineering (CIMNE), 2011)
      Text en actes de congrés
      Accés obert
      Principal balances are defined as a sequence of orthonormal balances which maximize successively the explained variance in a data set. Apparently, computing principal balances requires an exhaustive search along all possible ...
    • Principal balances 

      Pawlowsky Glahn, Vera; Egozcue Rubí, Juan José; Tolosana Delgado, Raimon (CIMNE, 2011)
      Text en actes de congrés
      Accés obert
      Principal balances are de ned as a sequence of orthonormal balances which maximize successively the explained variance in a data set. Apparently, computing principal balances requires an exhaustive search along all ...
    • The compositional meaning of a detection limit 

      Gerald van den Boogaart, K.; Tolosana Delgado, Raimon; Bren, Matevz (CIMNE, 2011)
      Text en actes de congrés
      Accés obert
      In compositional data analysis a value below detection limit (BDL) is typically modeled as the definitive information that the actual value is below some fixed value - the detection limit (see e.g. Palarea- Albaladejo ...
    • The compositional meaning of a detection limit 

      van den Boogaart, Karl Gerald; Tolosana Delgado, Raimon; Bren, Matevz (Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE), 2011)
      Text en actes de congrés
      Accés obert
      Conclusions The chemical interpretation of the detection limit and its stochastic model counterpart has thus different consequences for the statistical analysis than we would expect from the word by word interpretation of ...