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Actualitzat: fa 1 hora 53 minuts
Dij, 16/05/2013 - 11:59
Title: A novel condition monitoring scheme for bearing faults based on Curvilinear Component Analysis and hierarchical neural networks
Authors: Delgado Prieto, Miquel; Cirrincione,, Giansalvo; García Espinosa, Antonio; Ortega Redondo, Juan Antonio; Henao, Humberto
Abstract: Mostly the faults in electrical machines are
related with the bearings. Thus, a reliable bearing condition
monitoring scheme able to detect either local or distributed
defects are mandatory to avoid a breakdown in the machine.
So far, the research has been carried out mainly in the
detection of local faults, such as balls and raceways faults, but
surface roughness is not so reported. This paper deals with a
novel and reliable scheme capable to detect any fault that may
occur in a bearing, based on EXIN Curvilinear Component
Analysis, CCA, and Neural Network. The EXIN CCA, which
is an improvement of the Curvilinear Component Analysis,
has been conceived for data visualization, interpretation and
classification for real time industrial applications. The
effectiveness of this condition monitoring scheme has been
verified by experimental results obtained from different
operation conditions.
Dij, 16/05/2013 - 11:52
Title: Transactional access to shared memory in StarSs, a task based programming model
Authors: Gayatri, Rahulkumar; Badia Sala, Rosa Maria; Ayguadé Parra, Eduard; Lujan, M; Watson, I.
Abstract: With an increase in the number of processors on a single
chip, programming environments which facilitate the exploitation of par-
allelism on multicore architectures have become a necessity. StarSs is a
task-based programming model that enables a flexible and high level
programming. Although task synchronization in StarSs is based on data
flow and dependency analysis, some applications (e.g.
reductions
)require
locks
to access shared data.
Transactional Memory is an alternative to lock-based synchronization
for controlling access to shared data. In this paper we explore the idea of
integrating a lightweight Software Transactional Memory (STM) library,
TinySTM , into an implementation of StarSs (SMPSs). The SMPSs run-
time and the compiler have been modified to include and use calls to
the STM library. We evaluated this approach on four applications and
observe better performance in applications with high lock contention.
Dij, 16/05/2013 - 09:27
Title: The next city: low density territories in the metropolitan area of Barcelona
Authors: Sotoca García, Adolfo; Massuet, Maria
Abstract: In 2010 the Metropolitan Territorial Plan of Barcelona (PTMB) was approved. The plan is conceived as a strategic tool where some more specific and detailed planning will be framed in the next future. Some of the themes and challenges the detailed planning will be addressed to are here for the first time considered, since the scale the plan covers has been never approached before. For the first time the low density developments in this territory are faced as a whole phenomenon that needs to be readdressed. The Plan defines the “Specialized Residential Areas to Restructure” (AERR) which are low density residential areas in the form of continuous large-scale urban settlements, usually placed on steep areas, where physical conditions are critical to residential uses. These areas will be subject to further planning committed with the improvement the basic living conditions of its physical environment. This paper announces the description of these strategic lines which were applied in form of analysis over the AERR. The goal of the research is to obtain some useful criteria for further renewal of low density territories in the metropolitan area of Barcelona.
Dij, 16/05/2013 - 09:21
Title: RE-frame, RE-place, RE-site : three strategies for future housing environments
Authors: Sotoca García, Adolfo
Abstract: The paper states the need to rethink the planning approach that deals with housing developments of the future city. Considerations regarding the scale of the project, its role in a wider temporal context and the identity of the site where new extensions will be located,are necessary considerations in the field of urbanism. Between 2008 and 2009 Catalonia became a research field of exceptional interest in this series of reflections. During this short period of time a huge effort in planning and managing policies for housing development was done. AS a result of itthree major key Plans where undertaken by public administration. CSArquitectes, the planning office of which the author of the article is a founding partner, was the only invited firm to actively participate in all three processes. Through the description of CSArquitectes’ proposalsthe article argues the need to take in special consideration the concepts of scale, time and identity when planning new housing areas.
Dc, 15/05/2013 - 19:33
Title: Pk. Girona : parking tren station
Authors: Mias Gifré, Josep
Dc, 15/05/2013 - 18:39
Title: Optical filter cascading effects in a phase modulated coherent optical OFDM transmission system based on Hartley transform
Authors: Chochol, M.; Fabrega, J.M.; Svaluto Moreolo, Michela; Junyent Giralt, Gabriel
Abstract: Effects of cascading optical filters are investigated for a phase modulated coherent optical OFDM system based
on Hartley transform. The evaluation is performed by means of numeric simulations in a 10 Gb/s system with
a total bandwidth of 10 GHz. First a back-to-back (no fiber) case is assessed. Results show a 3 dB power penalty
after a single filter of only 68% of the signal bandwidth. The same penalty is achieved when cascading 10 filters
of 21.6 GHz bandwidth. Additionally, the penalties associated to the introduction of fiber spans between filters
are investigated.
Dc, 15/05/2013 - 18:33
Title: Special issue on power amplifier linearization
Authors: Wood, John; Bertran Albertí, Eduardo
Dc, 15/05/2013 - 18:18
Title: Compressive sensing for through wall radar imaging of stationary scenes using arbitrary data measurements
Authors: Lagunas Targarona, Eva; G. Amin, Moeness; Ahmad, Fauzia; Nájar Martón, Montserrat
Abstract: In this paper, we deal with removal of wall EM reflections prior to image reconstruction using step-frequency radars. The goal is to enable behind-the-wall target detection and localization from reduced data measurements. In the underlying problem, few frequency observations are available and they differ from one antenna position to another in a SAR imaging system.
Because of using a different set of frequencies for different antennas, direct applications of wall clutter mitigation methods, such as subspace and spatial filtering, prove ineffective. To provide these methods with the response measured at the same set of frequencies, a compressive sensing approach is used to reconstruct the range profiles. We use prior knowledge of the wall
standoff distance to speed up the convergence of the Orthogonal Matching Pursuit for sparse data reconstruction.
Dc, 15/05/2013 - 18:10
Title: Ranking and selection of unsupervised learning marketing segmentation
Authors: Sanchez Hernandez, German; Chiclana, Francisco; Agell Jané, Núria; Aguado Chao, Juan Carlos
Abstract: This paper addresses the problem of choosing the most appropriate classification from a given set of classifications of a set of patterns. This is a relevant topic on unsupervised systems and clustering analysis because different classifications can in general be obtained from the same data set. The provided methodology is based on five fuzzy criteria which are aggregated using an Ordered Weighted Averaging (OWA) operator. To this end, a novel multi-criteria decision making (MCDM) system is defined, which assesses the degree up to which each criterion is met by all classifications. The corresponding single evaluations are then proposed to be aggregated into a collective one by means of an OWA operator guided by a fuzzy linguistic quantifier, which is used to implement the concept of fuzzy majority in the selection process. This new methodology is applied to a real marketing case based on a business to business (B2B) environment to help marketing experts during the segmentation process. As a result, a segmentation containing three segments consisting of 35, 98 and 127 points of sale respectively is selected to be the most suitable to endorse marketing strategies of the firm. Finally, an analysis of the managerial implications of the proposed methodology solution is provided.
Dc, 15/05/2013 - 17:58
Title: Airborne wind retrieval using GPS delay-Doppler maps
Authors: Zavorotny, Valery; Rodríguez, Nereida; Akos, D.M.; Camps Carmona, Adriano José
Abstract: Global Navigation Satellite System Reflectometry (GNSSR)
has emerged recently as a promising remote sensing tool
to retrieve various geophysical parameters of Earth’s
surface. GNSS-reflected signals, after being received and
processed by the airborne or space-borne receiver, are
available as delay correlation waveforms or as delay-
Doppler maps. In the case of a rough ocean surface, those
characteristics can be related to the RMS of L-band limited
slopes of the surface waves, and from there to the surface
wind speed. The raw GNSS-reflected signal can be
processed either in real time by the receiver, or can be
recorded and stored onboard and post-processed in a
laboratory. The latter approach leveraging a software
receiver allows more flexibility while processing the raw
data. This work analyzes Delay Doppler Maps (DDM)
obtained as a result of processing of the data collected by the
GPS data logger/software receiver onboard the NOAA
Gulfstream-IV jet aircraft. Thereafter, the DDMs were used
to retrieve surface wind speed employing several different
metrics that characterize the DDM extent in the Doppler
frequency-delay domain. In contrast to previous works in
which winds have been retrieved by fitting the theoretically
modeled curves into measured correlation waveforms, here
we do not rely on any model for the determination. Instead,
the approach is based on a linear regression between DDMs
observables and the wind speeds obtained in simultaneous
GPS dropsonde measurements.
Dc, 15/05/2013 - 16:13
Title: Spatial noise reduction in broad area semiconductors
Authors: Herrero Simon, Ramon; Botey Cumella, Muriel; Pradeep Kumar, Nikhil; Staliunas, Kestutis
Dc, 15/05/2013 - 16:10
Title: Socially-aware emergent narrative
Authors: Álvarez Napagao, Sergio; Gómez Sebastià, Ignasi; Panagiotidi, Sofia; Tejeda Gómez, José Arturo; Oliva Felipe, Luis Javier; Vázquez Salceda, Javier
Abstract: In agent research, emergent narrative aims for practical solutions to the narrative paradox problem in both drama and interactive scenarios. At the same time, organisational frameworks can be used in games to provide flexibility, adaptiveness, or social-awareness. In this paper, we propose an extension of our cOncienS framework to support emergent narrative in games with two objectives: 1) provide social-awareness in emergent narrative by means of an organisational model, and 2) create convincing dynamic and flexible storytelling in games.
Dc, 15/05/2013 - 16:03
Title: High-speed debris-flows generating 2D impulse waves: Experimental analysis
Authors: Bregoli, Francesco; Bateman Pinzón, Allen; Medina Iglesias, Vicente César de
Abstract: When a landslide or a debris-flow falls in a water body, a big wave, known as impulse wave or
landslide tsunami wave, can be generated. That phenomenon can be highly destructive and unlikely predicted,
involving dams and shorelines. Disastrous past events have been extensively analyzed and experimental studies have been carried out by different authors, but do not fully account for the description of the phenomenon. In the present study we introduce a new experimental set up installed in the fluvial-morphodynamic laboratory of the GITS team in the Technical University of Catalonia. The experimental device consists of a wheeled box
sliding on a steep slope flume, releasing granular material, which enters a 2D basin. Defining a set of governing parameters and after several run of experiment, a description of the behavior of the waves was attempted. First results are here presented and analyzed.
Dc, 15/05/2013 - 13:39
Title: Modelling a linguistic variable as a hierarchical family of partitions induced by an indistinguishability operator
Authors: Soto, De A R; Recasens Ferrés, Jorge
Abstract: This work shows a method to obtain a hierarchy of partitions on the universe [0,1] in such a way that each of them is compatible with a refinement of Lukasiewicz indistinguishability operator. The classes of the partition at a given level present a relation of antonymy between them. Moreover, the partition at a certain level can be seen as the refinement of a previous level by means of a class of linguistic modifiers. Due to this fact, they seem appropriate for modeling linguistic labels of a linguistic variable. The associated indistinguishability operators show the increasing granularity when the number of classes rises up.
Dc, 15/05/2013 - 13:13
Title: The split of a working-class city: urban space, immigration and anarchism in inter-war Barcelona, 1914-1936
Authors: Oyón Bañales, José Luis
Abstract: Barcelona was the capital city of European anarchism during the inter-war years. The aim of this article is to discover the sociological and territorial features of the radicalized CNT (the Confederación Nacional del Trabajo), the anarchist union, which generated the summer 1936 revolution. By looking at the role of urban space as a variable in the collective processes of the working class the article argues that the unskilled recent immigrant worker and the neighbourhoods where this working-class figure was dominant were the key protagonists of revolutionary radicalism.
Dc, 15/05/2013 - 13:07
Title: Consequences of the Collision Between the Gas Ejected in the Collapse of a White Dwarf and a Low-Mass Star
Authors: Serichol Augué, Núria; García Senz, Domingo; Bravo Guil, Eduardo
Dc, 15/05/2013 - 12:19
Title: Working in the city: The knowledge city, experience from Barcelona's Metropolitan Centre
Authors: Marmolejo Duarte, Carlos Ramiro
Dc, 15/05/2013 - 12:10
Title: E-T-lipschitzian and E-T-kernel aggregation operators
Authors: Jacas Moral, Juan; Recasens Ferrés, Jorge
Abstract: Lipschitzian and kernel aggregation operators with respect to natural T-indistinguishability operators ET and their powers are studied. A t-norm T is proved to be ET-lipschitzian, and is interpreted as a fuzzy point and a fuzzy map as well. Given an archimedean t-norm T with additive generator t, the quasi-arithmetic mean generated by t is proved to be the most stable aggregation operator with respect to T.
Dc, 15/05/2013 - 12:05
Title: Aggregation of T-transitive Relations
Authors: Jacas Moral, Juan; Recasens Ferrés, Jorge
Abstract: This article studies the aggregation of transitive fuzzy relations. We first find operators that preserve transitivity and then extend the results to aggregating operators. As special cases, means and some kind of suitable ordered weighted averaging (OWAs) are used to aggregate transitive fuzzy relations with respect to an Archimedean t-norm. Three families of transitive relations that allow us to modify the entries of a given relation R continuously towards the smallest and the greatest ones in our universe are given. Aggregation of nonfinite families of transitive relations also is studied and applied to calculate the degree of inclusion or similarity of fuzzy quantities (fuzzy subsets of an interval of the real line). © 2003 Wiley Periodicals, Inc.
Dc, 15/05/2013 - 10:08
Title: Fuzzy t-transitive relations: eigenvectors and generators
Authors: Jacas Moral, Juan; Recasens Ferrés, Jorge
Abstract: After some preliminaries, the set of generators of a generalized equality relation (T-indistinguishability operator) is studied. This set is identified with the set of the eigenvectors of the relation. The relation between the fuzzy and “metric” topologies derived from these equalities is stablished. The concept of basis is introduced and the construction of a procedure in order to calculate explicitly a basis of a T-indistinguishability operator, for T archimedean, is proposed.