Time and Frequency Pruning for Speaker Identification

International audienceThis work is an attempt to refine decisions in speaker identification. A test utterance is divided into multiple time-frequency blocks on which a normalized likelihood score is calculated. Instead of averaging the block-likelihoods along the whole test utterance, some of them are rejected (pruning) and the final score is computed with a limited number of time-frequency blocks. The results obtained in the special case of time pruning lead the authors to experiment a joint time and frequency pruning approach. The optimal percentage of blocks pruned is learned on a tuning data set with the minimum identification error criterion. Validation of the time-frequency pruning process on 567 speakers leads to a significant error rate reduction (up to 41% reduction on TIMIT) for short training and test duration. ,QWURGXFWLRQ Mono-gaussian models for speaker recognition have been largely replaced by Gaussian Mixture Models (GMM) which are dedicated to modeling smaller clusters of speech. The Gaussian mixture modeling can be seen as a FRRSHUDWLRQ of models since the gaussian mixture density is a weighted linear combination of uni-modal gaussian densities. The work presented here is rather concerned with FRPSHWLWLRQ of models since different mono-gaussian models (corresponding to different frequency subbands) are applied to the test signal and the decision is made with the best or the N-best model scores. More precisely, a test utterance is divided into time-frequency blocks, each of them corresponding to a particular frequency subband and a particular time segment. During the recognition phase, the block scores are accumulated over the whole test utterance to compute a global score and take a final decision. In this work, we investigate accumulation using a hard threshold approach since some block scores are eliminated (pruning) and the final decision is taken with a subset of these scores. This approach should be robust in the case of a time-frequency localized noise since the least reliable time-frequency blocks can be removed. Even in the case of clean speech, some speaker test utterance blocks can be simply more similar to another speaker model than to the target speaker model itself. Removing these error-prone blocks should lead to a more robust decision. In 6HFWLRQ , a formalism is proposed to describe our block-based speaker recognition system. The potential of this approach is shown with a special case of the formalism: time pruning (6HFWLRQ). Experiments intended to find the optimal percentage of blocks pruned are described in 6HFWLRQ. The optimal parameters (percentage of blocks pruned) are validated on TIMIT and NTIMIT databases (6HFWLRQ). Finally, we summarize our main results and outline the potential advantages of the time-frequency pruning procedure in 6HFWLRQ .)RUPDOLVP 0RQRJDXVVLDQ µVHJPHQWDO ¶ PRGHOLQJ Let { } [ W W 0 1≤ ≤ be a sequence of M vectors resulting from the S-dimensional acoustic analysis of a speech signal uttered by speaker X. These vectors are summarized by the mean vector [ and the covariance matrix X: [ 0 [ ; 0 [ [ [

A new application of Internet of Things and Cloud Services in Analytical Chemistry: Determination of bicarbonate in water

[EN] In a constantly evolving world, new technologies such as Internet of Things (IoT) and cloud-based services offer great opportunities in many fields. In this paper we propose a new approach to the development of smart sensors using IoT and cloud computing, which open new interesting possibilities in analytical chemistry. According to IoT philosophy, these new sensors are able to integrate the generated data on the existing IoT platforms, so that information may be used whenever needed. Furthermore, the utilization of these technologies permits one to obtain sensors with significantly enhanced features using the information available in the cloud. To validate our new approach, a bicarbonate IoT-based smart sensor has been developed. A classical CO2 ion selective electrode (ISE) utilizes the pH information retrieved from the cloud and then provides an indirect measurement of bicarbonate concentration, which is offered to the cloud. The experimental data obtained are compared to those yielded by three other classical ISEs, with satisfactory results being achieved in most instances. Additionally, this methodology leads to lower-consumption, low-cost bicarbonate sensors capable of being employed within an IoT application, for instance in the continuous monitoring of HCO3- in rivers. Most importantly, this innovative application field of IoT and cloud approaches can be clearly perceived as an indicator for future developments over the short-term.This research was funded by the Spanish Ministerio de Economia y Competitividad, grant number DPI2016-80303-C2-1-P.Capella Hernández, JV.; Bonastre Pina, AM.; Ors Carot, R.; Peris Tortajada, M. (2019). A new application of Internet of Things and Cloud Services in Analytical Chemistry: Determination of bicarbonate in water. Sensors. 19(24):1-13. https://doi.org/10.3390/s19245528S1131924Perry, C. T., Salter, M. A., Harborne, A. R., Crowley, S. F., Jelks, H. L., & Wilson, R. W. (2011). Fish as major carbonate mud producers and missing components of the tropical carbonate factory. Proceedings of the National Academy of Sciences, 108(10), 3865-3869. doi:10.1073/pnas.1015895108Pandolfi, J. M., Connolly, S. R., Marshall, D. J., & Cohen, A. L. (2011). Projecting Coral Reef Futures Under Global Warming and Ocean Acidification. Science, 333(6041), 418-422. doi:10.1126/science.1204794Jaquet, J.-M., Nirel, P., & Martignier, A. (2013). Preliminary investigations on picoplankton-related precipitation of alkaline-earth metal carbonates in meso-oligotrophic lake Geneva (Switzerland). Journal of Limnology, 72(3), 50. doi:10.4081/jlimnol.2013.e50Lewis, C. N., Brown, K. A., Edwards, L. A., Cooper, G., & Findlay, H. S. (2013). Sensitivity to ocean acidification parallels natural pCO2 gradients experienced by Arctic copepods under winter sea ice. Proceedings of the National Academy of Sciences, 110(51), E4960-E4967. doi:10.1073/pnas.1315162110Kaloo, M. A., Sunder Raman, R., & Sankar, J. (2016). Novel structurally tuned DAMN receptor for «in situ» diagnosis of bicarbonate in environmental waters. The Analyst, 141(8), 2367-2370. doi:10.1039/c6an00218hBotta, A., de Donato, W., Persico, V., & Pescapé, A. (2016). Integration of Cloud computing and Internet of Things: A survey. Future Generation Computer Systems, 56, 684-700. doi:10.1016/j.future.2015.09.021Capella, J. V., Bonastre, A., Ors, R., & Peris, M. (2014). A step forward in the in-line river monitoring of nitrate by means of a wireless sensor network. Sensors and Actuators B: Chemical, 195, 396-403. doi:10.1016/j.snb.2014.01.039Dang, L. M., Piran, M. J., Han, D., Min, K., & Moon, H. (2019). A Survey on Internet of Things and Cloud Computing for Healthcare. Electronics, 8(7), 768. doi:10.3390/electronics8070768Lopez-Barbosa, N., Gamarra, J. D., & Osma, J. F. (2016). The future point-of-care detection of disease and its data capture and handling. Analytical and Bioanalytical Chemistry, 408(11), 2827-2837. doi:10.1007/s00216-015-9249-2Kassal, P., Steinberg, I. M., & Steinberg, M. D. (2013). Wireless smart tag with potentiometric input for ultra low-power chemical sensing. Sensors and Actuators B: Chemical, 184, 254-259. doi:10.1016/j.snb.2013.04.049Piyare, R., & Lee, S. R. (2013). Towards Internet of Things (IOTS): Integration of Wireless Sensor Network to Cloud Services for Data Collection and Sharing. International journal of Computer Networks & Communications, 5(5), 59-72. doi:10.5121/ijcnc.2013.5505Carminati, M., Mezzera, L., Ferrari, G., Sampietro, M., Turolla, A., Di Mauro, M., & Antonelli, M. (2018). A Smart Sensing Node for Pervasive Water Quality Monitoring with Anti-Fouling Self-Diagnostics. 2018 IEEE International Symposium on Circuits and Systems (ISCAS). doi:10.1109/iscas.2018.8351833Borrego, C., Ginja, J., Coutinho, M., Ribeiro, C., Karatzas, K., Sioumis, T., … Penza, M. (2018). Assessment of air quality microsensors versus reference methods: The EuNetAir Joint Exercise – Part II. Atmospheric Environment, 193, 127-142. doi:10.1016/j.atmosenv.2018.08.028Gervasi, O., Murgante, B., Misra, S., Gavrilova, M. L., Rocha, A. M. A. C., Torre, C., … Apduhan, B. O. (Eds.). (2015). Computational Science and Its Applications -- ICCSA 2015. Lecture Notes in Computer Science. doi:10.1007/978-3-319-21407-8LIU, Y., LIANG, Y., XUE, L., LIU, R., TAO, J., ZHOU, D., … HU, W. (2019). Polystyrene-coated Interdigitated Microelectrode Array to Detect Free Chlorine towards IoT Applications. Analytical Sciences, 35(5), 505-509. doi:10.2116/analsci.18p460Ping, H., Wang, J., Ma, Z., & Du, Y. (2018). Mini-review of application of IoT technology in monitoring agricultural products quality and safety. International Journal of Agricultural and Biological Engineering, 11(5), 35-45. doi:10.25165/j.ijabe.20181105.3092Alreshaid, A. T., Hester, J. G., Su, W., Fang, Y., & Tentzeris, M. M. (2018). Review—Ink-Jet Printed Wireless Liquid and Gas Sensors for IoT, SmartAg and Smart City Applications. Journal of The Electrochemical Society, 165(10), B407-B413. doi:10.1149/2.0341810jesDjelouat, H., Amira, A., & Bensaali, F. (2018). Compressive Sensing-Based IoT Applications: A Review. Journal of Sensor and Actuator Networks, 7(4), 45. doi:10.3390/jsan7040045Kassal, P., Steinberg, M. D., & Steinberg, I. M. (2018). Wireless chemical sensors and biosensors: A review. Sensors and Actuators B: Chemical, 266, 228-245. doi:10.1016/j.snb.2018.03.074Alahi, M. E. E., Xie, L., Mukhopadhyay, S., & Burkitt, L. (2017). A Temperature Compensated Smart Nitrate-Sensor for Agricultural Industry. IEEE Transactions on Industrial Electronics, 64(9), 7333-7341. doi:10.1109/tie.2017.2696508FIWARE Foundationhttps://www.fiware.org/Xie, X., & Bakker, E. (2013). Non-Severinghaus Potentiometric Dissolved CO2 Sensor with Improved Characteristics. Analytical Chemistry, 85(3), 1332-1336. doi:10.1021/ac303534

Nefroblastoma embrionario canino : caso clínico

Se describe un caso de nefroma embrionario canino o tumor de Wilms en un perro, macho, de dos meses de edad que presentaba distensión abdominal progresiva y pérdida de peso reciente. Se realiza una ecografía observándose una masa abdominal de gran tamaño. Se indica a los propietarios la necesidad de relizar una laparatomía exploratoria a la cual no acceden, pidiendo la eutanasia del animal. En la necropsia se aprecia el riñón derecho aumentado de tamaño y aspecto tumoral. El posterior estudio histológico confirmó el diagnóstico de nefroblastoma

Characterization of polypyrrole/phosphotungstate membranes by electrochemical impedance spectroscopy

The aim of this study was to design and prepare multifunctional PPy/PW12O403- membranes useful for the development of smart textile fabrics and wastewaters treatments based on the application of electrochemical techniques. These PPy/PW12O403- membranes have been characterized by means of electrochemical impedance spectroscopy by using electrochemical cells with different configurations based on the use of two-, three-, or four-electrode experiments. The activation energy of the films in the temperature range 35-70 degrees C was 170 meV. It has been demonstrated that after measuring the PPy films in different NaCl solutions, both the rate of ionic exchange and the diffusion processes through the membrane are faster for more concentrated solutions. Ionic exchange and diffusion were very prevented with a large cation as tetramethylammonium. The impedance spectra obtained with metal/polymer/electrolyte configuration show that the electrical conduction developed through coatings in strong acid solution is controlled by finite-length diffusion processes with reflective boundary conditions. At pH 13, the electrical response proceeds through the oxide layer (Fe and Cr oxides) and the steel/electrolyte interface. In this case, the polymeric coating is very porous due to the counter-ion disintegration. The decomposition of the counter-ion was corroborated by means of energy dispersive X-ray and Fourier transform infrared spectroscopy. (C) 2013 Elsevier B.V. All rights reserved.Authors thank to the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) and Universitat Politecnica de Valencia (Primeros Proyectos de Investigacion (PAID-06-10)) for the financial support. J. Molina is grateful to the Conselleria d'Educacio, Formacio i Ocupacio (Generalitat Valenciana) for the Programa VALi+D Postdoctoral Fellowship.Bonastre Cano, JA.; Molina Puerto, J.; Galvan, JC.; Cases Iborra, FJ. (2014). Characterization of polypyrrole/phosphotungstate membranes by electrochemical impedance spectroscopy. Synthetic Metals. 187:37-45. https://doi.org/10.1016/j.synthmet.2013.10.020S374518

Historical Building Monitoring Using an Energy-Efficient Scalable Wireless Sensor Network Architecture

We present a set of novel low power wireless sensor nodes designed for monitoring wooden masterpieces and historical buildings, in order to perform an early detection of pests. Although our previous star-based system configuration has been in operation for more than 13 years, it does not scale well for sensorization of large buildings or when deploying hundreds of nodes. In this paper we demonstrate the feasibility of a cluster-based dynamic-tree hierarchical Wireless Sensor Network (WSN) architecture where realistic assumptions of radio frequency data transmission are applied to cluster construction, and a mix of heterogeneous nodes are used to minimize economic cost of the whole system and maximize power saving of the leaf nodes. Simulation results show that the specialization of a fraction of the nodes by providing better antennas and some energy harvesting techniques can dramatically extend the life of the entire WSN and reduce the cost of the whole system. A demonstration of the proposed architecture with a new routing protocol and applied to termite pest detection has been implemented on a set of new nodes and should last for about 10 years, but it provides better scalability, reliability and deployment properties

DISCRIMINANT BINARY DATA REPRESENTATION FOR SPEAKER RECOGNITION

ABSTRACT In supervector UBM/GMM paradigm, each acoustic file is represented by the mean parameters of a GMM model. This supervector space is used as a data representation space, which has a high dimensionality. Moreover, this space is not intrinsically discriminant and a complete speech segment is represented by only one vector, withdrawing mainly the possibility to take into account temporal or sequential information. This work proposes a new approach where each acoustic frame is represented in a discriminant binary space. The proposed approach relies on a UBM to structure the acoustic space in regions. Each region is then populated with a set of Gaussian models, denoted as "specificities", able to emphasize speaker specific information. Each acoustic frame is mapped in the discriminant binary space, turning "on" or "off" all the specificities to create a large binary vector. All the following steps, speaker reference extraction, likelihood estimation or decision take place in this binary space. Even if this work is a first step in this avenue, the experiments based on NIST SRE 2008 framework demonstrate the potential of the proposed approach. Moreover, this approach opens the opportunity to rethink all the classical processes using a discrete, binary view

Evaluation of the capability of the PCV2 genome to encode miRNAs : lack of viral miRNA expression in an experimental infection

Porcine circovirus type 2 (PCV2) is a ssDNA virus causing PCV2-systemic disease (PCV2-SD), one of the most important diseases in swine. MicroRNAs (miRNAs) are a new class of small non-coding RNAs that regulate gene expression post-transcriptionally. Viral miRNAs have recently been described and the number of viral miRNAs has been increasing in the past few years. In this study, small RNA libraries were constructed from two tissues of subclinically PCV2 infected pigs to explore if PCV2 can encode viral miRNAs. The deep sequencing data revealed that PCV2 does not express miRNAs in an in vivo subclinical infection

Chemical and electrochemical study of fabrics coated with reduced graphene oxide

Polyester fabrics coated with reduced graphene oxide (RGO) have been obtained and later characterized by means of chemical and electrochemical techniques. X-ray photoelectron spectroscopy showed a decrease of the oxygen content as well as an increase of the sp2 fraction after chemical reduction of graphene oxide (GO). The electrical conductivity was measured by electrochemical impedance spectroscopy (EIS) and showed a decrease of 5 orders of magnitude in the resistance (¿) when GO was reduced to RGO. The phase angle also changed from 90° for PES-GO (capacitative behavior) to 0° for RGO coated fabrics (resistive behavior). In general an increase in the number of RGO layers produced an increase of the conductivity of the fabrics. EIS measurements in metal/sample/electrolyte configuration showed better electrocatalytic properties and faster diffusion rate for RGO specimens. Scanning electrochemical microscopy was employed to test the electroactivity of the different fabrics obtained. The sample coated with GO was not conductive since negative feedback was obtained. When GO was reduced to RGO the sample behaved like a conducting material since positive feedback was obtained. Approach curves indicated that the redox mediator had influence on the electrochemical response. The Fe(CN)63¿/4¿ redox mediator produced a higher electrochemical response than Ru(NH3)63+/2+ one.Authors thank to the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) and Universitat Politecnica de Valencia (Vicerrectorado de Investigacion PAID-06-10 contract 003-233) for the financial support. J. Molina is grateful to the Conselleria d'Educacio (Generalitat Valenciana) for the FPI fellowship. A.I. del Rio is grateful to the Spanish Ministerio de Ciencia y Tecnologia for the FPI fellowship. J.C. Galvan is gratefully acknowledged for help with EIS measurements and data analysis.Molina Puerto, J.; Fernández Sáez, J.; Del Río García, AI.; Bonastre Cano, JA.; Cases Iborra, FJ. (2013). Chemical and electrochemical study of fabrics coated with reduced graphene oxide. Applied Surface Science. 279:46-54. https://doi.org/10.1016/j.apsusc.2013.04.020S465427

Electrochemical synthesis of polypyrrole doped with graphene oxide and its electrochemical characterization as membrane material

Polypyrrole (PPy) doped with graphene oxide (GO) has been electrochemically obtained by potentiostatic synthesis and its electrochemical behavior as membrane material has been studied for the first time. Fourier transform infrared spectroscopy with attenuated total reflection showed the formation of the hybrid material due to presence of PPy and GO bands. Field emission scanning electron microscopy micrographs showed the effective incorporation of GO sheets and the formation of a 3-D porous material with high surface area. Scanning electrochemical microscopy of PPy/GO films showed positive feedback close to the ideal conducting behavior, indicating a good electroactivity. Electrochemical impedance spectroscopy (EIS) was employed to measure the electrochemical properties of the coatings by two-, three-, and four-electrode configurations. The electronic conductivity of PPy/GO film, measured between two metallic conductors, was 4.7·10−6 S/cm. Its ionic conductivity was superior (1.6·10−3 S/cm) due to the high porosity of the material as demonstrated by cyclic voltammetry and EIS measurements, where the PPy/GO film was employed as a free-standing membrane. The diffusion-migration rate of tetramethylammonium chloride was very similar to sodium chloride when present in the same concentration, which indicated no influence of the size of the electrolyte conductor due to the high porosity. © 2016 Elsevier B.V. All rights reserved.Authors wish to thank the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) for the financial support. J. Molina is grateful to the Conselleria d'Educacio, Formacio i Ocupacio (Generalitat Valenciana) for the Programa VALi+D Postdoctoral Fellowship (APOSTD/2013/056). A.I. del Rio is grateful to the Spanish Ministerio de Ciencia y Tecnologia for her FPI fellowship. Electron Microscopy Service of the UPV (Universitat Politecnica de Valencia) is gratefully acknowledged for help with FESEM and EDX characterization.Molina Puerto, J.; Bonastre Cano, JA.; Fernández Sáez, J.; Del Río García, AI.; Cases Iborra, FJ. (2016). Electrochemical synthesis of polypyrrole doped with graphene oxide and its electrochemical characterization as membrane material. Synthetic Metals. 220:300-310. https://doi.org/10.1016/j.synthmet.2016.06.028S30031022