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Tejedor J.,University of Alcalá | Toledano D.T.,Autonomous University of Madrid | Lopez-Otero P.,Campus Universitario Of Vigo | Docio-Fernandez L.,Campus Universitario Of Vigo | Garcia-Mateo C.,Campus Universitario Of Vigo
Eurasip Journal on Audio, Speech, and Music Processing | Year: 2016

Query-by-example spoken term detection (QbE STD) aims at retrieving data from a speech repository given an acoustic query containing the term of interest as input. Nowadays, it is receiving much interest due to the large volume of multimedia information. This paper presents the systems submitted to the ALBAYZIN QbE STD 2014 evaluation held as a part of the ALBAYZIN 2014 Evaluation campaign within the context of the IberSPEECH 2014 conference. This is the second QbE STD evaluation in Spanish, which allows us to evaluate the progress in this technology for this language. The evaluation consists in retrieving the speech files that contain the input queries, indicating the start and end times where the input queries were found, along with a score value that reflects the confidence given to the detection of the query. Evaluation is conducted on a Spanish spontaneous speech database containing a set of talks from workshops, which amount to about 7 h of speech. We present the database, the evaluation metric, the systems submitted to the evaluation, the results, and compare this second evaluation with the first ALBAYZIN QbE STD evaluation held in 2012. Four different research groups took part in the evaluations held in 2012 and 2014. In 2014, new multi-word and foreign queries were added to the single-word and in-language queries used in 2012. Systems submitted to the second evaluation are hybrid systems which integrate letter transcription- and template matching-based systems. Despite the significant improvement obtained by the systems submitted to this second evaluation compared to those of the first evaluation, results still show the difficulty of this task and indicate that there is still room for improvement. © 2016, Tejedor et al.


Linke B.,Leibniz Institute for Agricultural Engineering | Rodriguez-Abalde A.,Campus Universitario Of Vigo | Jost C.,Leibniz Institute for Agricultural Engineering | Krieg A.,HAWK University of Applied Sciences and Arts
Bioresource Technology | Year: 2015

This study investigated the potential of producing biogas on demand from maize silage using a novel two-phase continuously fed leach bed reactor (LBR) which is connected to an anaerobic filter (AF). Six different feeding patterns, each for 1week, were studied at a weekly average of a volatile solids (VS) loading rate of 4.5gL-1d-1 and a temperature of 38°C. Methane production from the LBR and AF responded directly proportional to the VS load from the different daily feeding and resulted in an increase up to 50-60% per day, compared to constant feeding each day. The feeding patterns had no impact on VS methane yield which corresponded on average to 330Lkg-1. In spite of some daily shock loadings, carried out during the different feeding patterns study, the reactor performance was not affected. A robust and reliable biogas production from stalky biomass was demonstrated. © 2014 Elsevier Ltd.


Fontani M.,University of Siena | Argones-Rua E.,Campus Universitario Of Vigo | Troncoso C.,Campus Universitario Of Vigo | Barni M.,University of Siena
Proceedings of the 2013 IEEE International Workshop on Information Forensics and Security, WIFS 2013 | Year: 2013

Image Forensics (IF) is a challenging research topic, that suffers from strong limitations when facing with real world applications. A possible way to cope with these limitations is to resort to data fusion, whereby the outputs of different forensic tools are used to reach a final decision about the analyzed image. Nevertheless, existing schemes do not take full advantage of all the information available to the analyst, like the knowledge of the dependence of the performance of forensic tools on side conditions. Specifically, in this paper we show how the performance of forensic tools varies according to a number of parameters, most of which are directly observable by the analyst. After showing some practical examples, we propose a method to cast this background information into two multi-clue information fusion frameworks, yielding a significant improvement of the overall performance at virtually no cost. © 2013 IEEE.


Chaves-Dieguez D.,University of Vigo | Pellitero-Rivero A.,University of Vigo | Garcia-Coego D.,Campus Universitario Of Vigo | Gonzalez-Castano F.J.,University of Vigo | And 4 more authors.
Sensors (Switzerland) | Year: 2015

Smart cities are expected to improve the quality of life of citizens by relying on new paradigms, such as the Internet of Things (IoT) and its capacity to manage and interconnect thousands of sensors and actuators scattered across the city. At the same time, mobile devices widely assist professional and personal everyday activities. A very good example of the potential of these devices for smart cities is their powerful support for intuitive service interfaces (such as those based on augmented reality (AR)) for non-expert users. In our work, we consider a scenario that combines IoT and AR within a smart city maintenance service to improve the accessibility of sensor and actuator devices in the field, where responsiveness is crucial. In it, depending on the location and needs of each service, data and commands will be transported by an urban communications network or consulted on the spot. Direct AR interaction with urban objects has already been described; it usually relies on 2D visual codes to deliver object identifiers (IDs) to the rendering device to identify object resources. These IDs allow information about the objects to be retrieved from a remote server. In this work, we present a novel solution that replaces static AR markers with dynamic markers based on LED communication, which can be decoded through camerasembedded in smartphones. These dynamic markers can directly deliver sensor information to the rendering device, on top of the object ID, without further network interaction. © 2015, by the authors; licensee MDPI, Basel, Switzerland.


Torio P.,CI Ricardo Torres Quiroga 11 1oE | Garcia Sanchez M.,Campus Universitario Of Vigo
IEEE Antennas and Propagation Magazine | Year: 2010

This paper presents an algorithm and a program to generate radio-frequency impulsive noise for use as a source for a signalgenerator or simulation program. From the research of several authors, the paper justifies how to generate the impulsive noise using few parameters in a simple way. The impulsive noise generated is configurable in terms of length, occurrence rate, and power of the pulses. The generator is useful for testing the immunity of real or simulated radio communication systems against impulsive noise. © 2010 IEEE.


Gomez-Cuba F.,Campus Universitario Of Vigo | Asorey-Cacheda R.,University of Vigo | Gonzalez-Castano F.J.,Campus Universitario Of Vigo
IEEE PES Innovative Smart Grid Technologies Conference Europe | Year: 2012

This paper addresses specific smart grid communication requirements. It considers a last-mile network based on an IEEE 802.16 cell deployed to cover a group of customers and serve their Energy Services Interfaces. Based on the communication requirements of smart grid last-mile applications and entities, we propose a traffic priority model and setup for the WiMAX air interface. Finally, we evaluate the proposal using a discrete-event simulator. © 2012 IEEE.


Gomez-Cuba F.,Campus Universitario Of Vigo | Asorey-Cacheda R.,University of Vigo | Gonzalez-Castano F.J.,Campus Universitario Of Vigo | Gonzalez-Castano F.J.,University of Vigo
IEEE Transactions on Smart Grid | Year: 2013

This paper addresses the modeling of specific Smart Grid (SG) communication requirements from a data networking research perspective, as a general approach to the study of different access technologies suitable for the last mile (LM). SGLM networks serve customers' Energy Services Interfaces. From functional descriptions of SG, a traffic model is developed. It is then applied to the study of an access architecture based on leased lines from local broadband access providers. This permits consideration of the potential starvation of domestic traffic, which is avoided by applying well-known traffic management techniques. From previous results obtained for a purpose-built WiMAX SGLM network, the intuition that a leased broadband access yields lower latencies is verified. In general, the proposed traffic model simplifies the design of benchmarks for the comparison of candidate access technologies. © 2012 IEEE.


Argones Rua E.,Campus Universitario Of Vigo | Garcia Salomon F.J.,Campus Universitario Of Vigo | Perez-Freire L.,Campus Universitario Of Vigo
Proceedings of the ACM Conference on Computer and Communications Security | Year: 2013

A successful deployment of biometric-based recognition systems in real-life applications depends on crucial issues such as data security and privacy, which have to be specifically addressed. Besides, cryptographic key protection can represent the main weakness of a secured transmission. In this demonstration a system for encryption and digital signature of generic digital documents (SAES, standing for Signature-based Assymetric Encryption System) is presented, where cryptographic keys are protected by the hand-written signature of the user. Furthermore, a demonstration of a the handwritten online signature verification system (SVS) based on non-protected templates will also be performed. © 2013 Authors.


Rodriguez-Ramilo S.T.,Instituto Nacional Of Investigacion Y Tecnologia Agraria Y Alimentaria Inia | Rodriguez-Ramilo S.T.,Campus Universitario Of Vigo | Toro M.A.,Instituto Nacional Of Investigacion Y Tecnologia Agraria Y Alimentaria Inia | Toro M.A.,Technical University of Madrid | Fernandez J.,Instituto Nacional Of Investigacion Y Tecnologia Agraria Y Alimentaria Inia
Spanish Journal of Agricultural Research | Year: 2010

Molecular markers have been successfully used to distinguish between livestock species and breeds not closely related, for example through the clustering methodology. However, the differentiation between purebred and crossbred individuals would be an appealing purpose that has been little explored. In this study three clustering approaches are tested for their ability to detect crossbred individuals and to separate them from pure ones. Real microsatellite data from Iberian and Duroc breeds were utilised as an example. Simulated F1, Iberian and Duroc backcrossed individuals obtained from the real microsatellite were also assessed. The results of this study indicate that the clustering methods showed a reduced ability to detect the original subpopulations (Iberian breed, Duroc breed, F1, Iberian backcross and Duroc backcross). Reasons for such performance could be the absence of Hardy-Weinberg and linkage equilibrium within the subpopulations and the fact that the Iberian group was compound by individuals belonging to different strains. To test the influence of these factors an allele randomisation procedure was performed within each subpopulation. After that, none of the methods recovered the five groups, but the algorithm implemented in BAPS (Bayesian analysis of population structure) gave a partition where pure Iberian individuals were separated for the rest. It can be concluded that the lack of homogeneity within groups is the main cause of the reduced accuracy of the clustering methods in the separation of pure and crossed individuals.


Tuset V.M.,CSIC - Institute of Marine Sciences | Farre M.,CSIC - Institute of Marine Sciences | Otero-Ferrer J.L.,Campus Universitario Of Vigo | Vilar A.,Facultade de Informatica | And 2 more authors.
Marine and Freshwater Research | Year: 2016

To check the suitability of otoliths for measuring biodiversity, the contour and shape of the sulcus acusticus of sagittal otoliths were described using geometric morphological analysis. Thirteen and fourteen points were used to define these structures respectively. Three current coastal fish assemblages of the north-western Mediterranean were selected for the present study. The results demonstrate that the relative warps generated in the geometric analysis explained both characteristics related to contour and the otolith sulcus. A comparative study with body fish shape using morphospaces and clusters revealed that otolith shape is a better variable for explaining the ecological structure of a fish assemblage. Moreover, three morphological indices (morphological richness (MR), morphological disparity and the morphogeometric index) were estimated from relative warps of otoliths and were compared with ecological, taxonomic, functional and morphological (from body shape) indices. MR increased with functional diversity and average taxonomic distinctness, reflecting the ecological and taxonomic character of otolith morphology. These findings suggest that otoliths could be a useful tool for studying the diversity of present and past fish assemblages. © 2016 CSIRO.

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