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Ghaderi M.,Ramon Llull University | Ruiz F.,BarcelonaTech | Agell N.,Ramon Llull University
Pattern Recognition Letters | Year: 2015

What is the role that colour plays in perception of a brand by customers? How can we explore the cognitive role that colour plays in determining brand perception? To answer these questions we propose a preference disaggregation method based on multi-criteria decision aid. We identify the criteria aggregation model that underlies the global preference of a brand with respect to each brand image attribute. The proposed method is inspired by the well-known UTASTAR algorithm, but unlike the original formulation, it represents preferences by means of non-monotonic value functions. The method is applied to a database of brands ranked on each brand image attribute. For each brand image attribute, non-monotonic marginal value functions from each component of the brand colour are obtained separately. These functions contain the fitness between each colour component and each brand image attribute, in an understandable manner. © 2015 Published by Elsevier B.V.

Ruiz F.J.,BarcelonaTech | Raya C.,BarcelonaTech | Sama A.,BarcelonaTech | Agell N.,Ramon Llull University
Pattern Recognition Letters | Year: 2015

A new formulation of the central ideas of Boden's well-established theory on combinational, exploratory and transformational creativity is presented. This new formulation, based on the idea of conceptual space, redefines some terms and includes several types of concept properties (appropriateness and relevance), whose relationship facilitates the computational implementation of the transformational creativity mechanism. The presented formulation is applied to a real case of chocolate designing in which a novel and flavorful combination of chocolate and fruit is generated. The experimentation was conducted jointly with a Spanish chocolate chef. Experimental results prove the relationship between appropriateness and relevance in different frameworks and show that the formulation presented is not only useful for understanding how the creative mechanisms of design works but also facilitates its implementation in real cases to support creativity processes. © 2015 Elsevier B.V. All rights reserved.

Ghaderi M.,Ramon Llull University | Ruiz F.J.,BarcelonaTech. | Agell N.,Ramon Llull University
Frontiers in Artificial Intelligence and Applications | Year: 2014

In this paper we explore the possibility of capturing color trends and understanding the rationale behind the popularity of a color. To this end, we propose using a preference disaggregation approach from the field of Multi-Criteria Decision Analysis. The main objective is to identify the criteria aggregation model that underlies the global preference of a color. We introduce a new disaggregation method based on the well-known UTASTAR algorithm able to represent preferences by means of non-monotonic utility functions. The method is applied to a large database of ranked colors, from three different years, based on the information published on the webpage of an international creative community. Non-monotone marginal utility functions from each of the coordinates are obtained for each year. These functions contain the color preference information captured, in an understandable way.

Ruiz F.J.,BarcelonaTech | Raya C.,BarcelonaTech | Sama A.,BarcelonaTech | Agell N.,Ramon Llull University
Frontiers in Artificial Intelligence and Applications | Year: 2014

In this paper, a new formulation of the central ideas of the well-established theory of Boden about creativity is presented. This new formulation redefines some terms and reviews the formal mechanisms of exploratory and transformational creativity. The presented approach is based on the conceptual space proposed by Boden and formalized by other authors in a way that facilitates the implementation of these mechanisms. The presented formulation is applied to a the real case of creative designing in which a new combination of chocolate and fruit is desired. The experimentation has been conducted jointly with a Spanish chocolate chef. Data collected from the chef has been used to validate the proposed system. Experimental results show that the formulation presented is not only useful for understanding how the creative mechanisms of design works, but also facilitates its implementation in real cases to support creativity processes.

Nguyen P.-L.,Loughborough University | Zhong Q.-C.,Loughborough University | Blaabjerg F.,University of Aalborg | Guerrero J.M.,BarcelonaTech.
Proceedings of the 2012 7th IEEE Conference on Industrial Electronics and Applications, ICIEA 2012 | Year: 2012

The operating principles of static synchronous condenser (STATCOM) are similar to that of a rotating synchronous condenser. However, so far, most controlling methods proposed for STATCOM have not taken into account the internal characteristics of rotational synchronous machines. In this paper, following the idea of synchronverters, the controller for a STATCOM is designed according to the mathematical model of synchronous generators that are operated in the compensator mode. As a result, no phase-locked loop (PLL) is needed. Moreover, a third operation mode, i.e. the droop control mode (or the D-mode in short), is introduced to the operation of STATCOM, in addition to the conventional voltage regulation mode (or the V -mode in short) and the direct Q control mode (or the Q-mode in short). This allows parallel-operated STATCOMs to share reactive power properly. The proposed control strategy is verified with simulations in MATLAB/Simulink/SimPowerSystems. © 2012 IEEE.

Rapisarda D.,CIEMAT | Palermo I.,CIEMAT | Gonzalez M.,CIEMAT | Martin-Fuertes F.,CIEMAT | And 4 more authors.
Proceedings - Symposium on Fusion Engineering | Year: 2016

Within the framework of EUROfusion Program, the Dual Coolant Lithium Lead (DCLL) is one of the four EU breeder blanket concepts that are being investigated as candidate for DEMO. DCLL uses PbLi as main coolant, tritium breeder, tritium carrier and neutron multiplier. The main structures, including the first wall, are cooled with helium. The EU program proposed for the next years will consider a low temperature version of DCLL (limited to 550 °C) in order to allow the use of conventional materials and technologies. During the first year of EUROfusion activities a draft design of the DCLL has been proposed. The main blanket performances were adapted to the new specifications and CAD model of DEMO. The breeder zone has been toroidally divided into 4 parallel PbLi circuits, separated through stiffening grid radial walls. The PbLi flow routing has been designed to maximize the amount of thermal power extracted by flowing PbLi and to avoid the occurrence of reverse flows due to volumetric heating. Thermal-hydraulics, MHD and neutronics calculations have been performed for the first draft design. The new DCLL design employs Eurofer-Alumina-Eurofer sandwich as flow channel insert (FCI). © 2015 IEEE.

Hurlimann M.,BarcelonaTECH | Hurlimann M.,Swiss Federal Institute of forest | McArdell B.W.,Swiss Federal Institute of forest | Rickli C.,Swiss Federal Institute of forest
Geomorphology | Year: 2015

Hillslope debris flows are unconfined flows that originate by shallow failures in unconsolidated material at steep slopes. In spite of their significant hazard for persons and infrastructure in mountainous regions, research on hillslope debris flows is rather scarce in comparison to other landslide types. This study focusses on the runout characteristics of hillslope debris flows applying two different approaches. First, detailed landslide inventories, which include field measurements of 548 slope failures that occurred during the last two decades in seven parts of Switzerland, were analysed. Second, laboratory tests were carried out to study the effect of the soil water content, grain-size distribution and mobilized volume on the runout behaviour of hillslope debris flows. Most of the failures in the field started as shallow translational slides at terrain slopes between 25° and 45° and involved volumes of some tens to a few hundred cubic meters. An analysis of the runout distance of 117 hillslope debris flows showed that they normally travelled some tens of meters, but sometimes the runout exceeded 300m. A positive relation between volume and runout distance and between volume and affected area was observed, although there is considerable scatter in the data. The affected area of 63 hillslope debris flows ranged from ~100 to ~1500m2. Based on the field data, a 7.5m long laboratory hillslope was designed with a geometrical scale factor of 20. A total of 75 runs with volumes from 4 to 20dm3, water contents from 18% to 38%, and four grain-size distributions were carried out. The laboratory tests revealed that water content is the dominant control, but also the clay content strongly influences the runout distance and the affected area. Even a small increase in water or clay content produces a considerably larger or smaller runout distance, respectively. In contrast, the influence of the volume on the runout was smaller, and a positive relation was observed between these two parameters. The field and laboratory results are in general agreement and consistent with the results of other studies. The results of this work improve the understanding of hillslope debris flows and may aid in the hazard assessments of these processes. © 2014 Elsevier B.V.

Medina E.,BarcelonaTech | Kawsar F.,Alcatel - Lucent | Meseguer R.,BarcelonaTech | Ochoa S.F.,University of Chile
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Most activity-aware systems designed to support mobile workers in dynamic environments, such as hospitals or industrial plants, typically consider the use of mobile devices and large displays. However, we envision potential benefits of using ubiquitous micro-displays as support of mobile workers activities. Particularly, in this paper we show how the use of situated micro-displays, as a mechanism for embedding information into a physical environment, can contribute to improve the performance and experience of mobile workers in those scenarios. The article also describes the prototype of a micro-display network designed to support people performing spatially distributed activities. It also presents a user study that helps understand how the spatial distribution of situated micro-displays impacts on the mobile workers performance. © 2014 Springer International Publishing Switzerland.

Ruiz F.,BarcelonaTech | Sama A.,BarcelonaTech | Agell N.,ESADE URL
Frontiers in Artificial Intelligence and Applications | Year: 2012

Action learning is a methodology based on a machine learning system that makes it possible to select a suitable action or sequence of actions given a state. The main drawback of this methodology is the difficulty of assigning a class to the state-action pair to be included in the training set. This paper proposes an active learning methodology in the learning phase of an action learning process. With the help of an artificial example, the active methodology is compared with a passive methodology consisting of randomly selecting the training set from the pool of unlabelled patterns. © 2012 The authors and IOS Press. All rights reserved.

Melia U.S.P.,Barcelonatech | Melia U.S.P.,Biomedical Engineering Research Center | Vallverdu M.,Barcelonatech | Vallverdu M.,Biomedical Engineering Research Center | And 5 more authors.
Journal of Medical and Biological Engineering | Year: 2013

Deoxyribonucleic acid (DNA) information is discrete in both "time" (sequence positions) and "amplitude" (nucleotide values). This permits the use of signal processing techniques for its characterization. The conversion of DNA nucleotide symbols into discrete numerical values enables signal processing to be employed to solve problems related to sequence analysis, such as finding coding sequences. In this work, a numerical conversion method was chosen based on the thermodynamic data of free energy changes (ΔG°) of the formation of a duplex structure of DNA or ribonucleic acid (RNA), associated with the nucleotide sequence pre-mRNA (messenger RNA). The aim of this work was to characterize coding regions (exons) from non-coding regions (introns) using a methodology based on time-frequency representation (TFR). This permits the observation of the evolution of the periodicity and frequency components with time, introducing more variables related to the gene sequences compared to those used in traditional fast Fourier transform analysis. The parameters calculated from TFR are instantaneous frequency and instantaneous power. It was found that instantaneous frequency and power variables in different frequency bands allowed the correct classification between exons and introns with a prediction accuracy of more than 85%.

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