995 research outputs found

    Correction system for polyphonic piano recordings

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    M.I. Martin-Erdozain, I. Barbancho, A. Rosa-Pujazon, A.M. Barbancho, "Correction system for polyphonic piano recordings", XXVIII Simposium Nacional de la Unión Científica Internacional de Radio, Santiago de Compostela, España, 2013n this paper, a support tool for piano rehearsal is presented. The system analyses a given piano polyphonic recording to find the times, pitch and duration of the notes and figures played, taking into account the possibility of playing more than one note simultaneously as well as covering the whole piano frequency range. In order to do so, the system uses an onset detection algorithm to segment the input signal into partitions which are then analysed in the time and frequency domains. Then, the system correlates the data extracted from the partitions with the score of the original piece, identifying the positions and type of the mistakes performed by the user, and providing her/him with the corresponding feedback. The experiments conducted showed that the application is capable of analysing a given recording and indicate the musician the mistakes made.This work has been funded by the Ministerio de Economia y Competitividad of the Spanish Government under Project No. TIN2010-21089-C03-02 and by the Ministerio de Industria, Turismo y Comercio under Project No. TSI-090100-2011-25

    Conducting a virtual ensemble with a kinect device

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    This paper presents a gesture-based interaction technique for the implementation of an orchestra conductor and a virtual ensemble, using a 3D camera-based sensor to capture user’s gestures. In particular, a human-computer interface has been developed to recognize conducting gestures using a Microsoft Kinect device. The system allows the conductor to control both the tempo in the piece played as well as the dynamics of each instrument set independently. In order to modify the tempo in the playback, a time-frequency processing-based algorithmis used. Finally, an experiment was conducted to assess user’s opinion of the system as well as experimentally confirm if the features in the system were effectively improving user experience or not.This work has been funded by the Ministerio de Economia y Competitividad of the Spanish Government under Project No. TIN2010-21089-C03-02 and Project No. IPT-2011-0885-430000 and by the Junta de Andalucia under Project No. P11-TIC-7154. The work has been done at Universidad de Malaga. Campus de Excelencia Internacional Andalucia Tech

    Multi-Wavelength Fiber Lasers

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    Low-cost step aerobics system with virtual aerobics trainer

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    In this paper a low-cost step-aerobics instructor simulation system is presented. The proposed system analyses a given song to iden- tify its rhythmic pattern. Subsequently, this rhythmic pattern is used in order to issue a set of steps-aerobics commands to the user, thus simu- lating a training session. The system uses a Wii Balance Board to track exercises performed by users and runs on an Android smartphone. A set of tests were conducted to assess user experience and opinion on the system developed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Análisis de la calidad de servicio en el restaurante la Proa Pimentel, 2019

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    La presente investigación se planteó como objetivo general evaluar la calidad de servicio en el restaurante La Proa Pimentel. La investigación es de tipo descriptiva con enfoque mixto. Para diagnosticar la situación actual de la Proa Pimentel se elaboró un análisis FODA del restaurante, también se aplicó un cuestionario según el modelo de medición de calidad SERVPERF para determinar la percepción de calidad de los clientes en el restaurante la Proa Pimentel. El cuestionario está conformado por 22 preguntas distribuidas en 5 dimensiones, donde el tamaño muestra fue de 230 clientes. La confiabilidad se obtuvo de 0.933, demostrando un alto grado de correlación entre los elementos que conforman el instrumento empleado en la presente investigación. Los resultados obtenidos en relación a las dimensiones indicaron un 88% de clientes están conformes con la dimensión de elementos tangibles, en fiabilidad un 88% manifestaron estar conformes con la confianza que brinda el restaurante, capacidad de respuesta un 87% señalaron que el servicio es rápido, en seguridad 94% están de acuerdo con la amabilidad de los trabajadores y finalmente empatía un 85% resaltaron que los horarios de atención son óptimos. Se concluye que el restaurante, cuenta con una calidad total de nivel 4 (de acuerdo) según en la escala Likert percibida por los clientes, contando con una ubicación estratégica cerca al balneario de Pimentel, deficiencia en la atención personalizada, los trabajadores carecen de conocimientos para responder las inquietudes y presenta registros de errores en los pedidos

    "Capital Stock and Unemployment: Searching for the Missing Link"

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    The purpose of this paper is to examine the proposition that capital stock relative to aggregate output has been an important variable in the determination of the U.S. NAIRU (Non-Accelerating Inflation Rate of Unemployment) over the last four decades. We present new empirical evidence, obtained from the application of the cointegrated VAR methodology to U.S. time-series data, that lends strong support to the claim that the aggregate capital-output ratio, the real price of imports, and aggregate capacity utilization were determinants of the NAIRU in the period considered. The same evidence also shows that technical progress and changes in long-term unemployment did not affect the NAIRU. We believe this evidence suggests that, insofar as the aggregate capital-output ratio is affected by changes in real interest rates, the stance of monetary policy is one determinant of the NAIRU.

    Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease?

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    Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host’s innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease.Fil: Morrot, Alexandre. Universidade Federal do Rio de Janeiro; BrasilFil: Villar, Silvina Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; ArgentinaFil: González, Florencia Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; ArgentinaFil: Perez, Ana Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; Argentin

    A database and digital signal processing framework for the perceptual analysis of voice quality

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    Bermúdez de Alvear RM, Corral J, Tardón LJ, Barbancho AM, Fernández Contreras E, Rando Márquez S, Martínez-Arquero AG, Barbancho I. A database and digital signal processing framework for the perceptual analysis of voice quality. Pan European Voice Conferenc: PEVOC 11 Abstract Book. Aug. 31-Sept.2, 2015.Introduction. Clinical assessment of dysphonia relies on perceptual as much as instrumental methods of analysis [1]. The perceptual auditory analysis is potentially subject to several internal and external sources of bias [2]. Furthermore acoustic analyses which have been used to objectively characterize pathological voices are likely to be affected by confusion variables such as the signal processing or the hardware and software specifications [3]. For these reasons the poor correlation between perceptual ratings and acoustic measures remains to be a controversial matter [4]. The availability of annotated databases of voice samples is therefore of main importance for clinical and research purposes. Databases to perform digital processing of the vocal signal are usually built from English speaking subjects’ sustained vowels [5]. However phonemes vary from one language to another and to the best of our knowledge there are no annotated databases with Spanish sustained vowels from healthy or dysphonic voices. This work shows our first steps to fill in this gap. For the aim of aiding clinicians and researchers in the perceptual assessment of voice quality a two-fold objective was attained. On the one hand a database of healthy and disordered Spanish voices was developed; on the other an automatic analysis scheme was accomplished on the basis of signal processing algorithms and supervised learning machine techniques. Material and methods. A preliminary annotated database was created with 119 recordings of the sustained Spanish /a/; they were perceptually labeled by three experienced experts in vocal quality analysis. It is freely available under Links in the ATIC website (www.atic.uma.es). Voice signals were recorded using a headset condenser cardioid microphone (AKG C-544 L) positioned at 5 cm from the speaker’s mouth commissure. Speakers were instructed to sustain the Spanish vowel /a/ for 4 seconds. The microphone was connected to a digital recorder Edirol R-09HR. Voice signals were digitized at 16 bits with 44100 Hz sampling rate. Afterwards the initial and last 0.5 second segments were cut and the 3 sec. mid portion was selected for acoustic analysis. Sennheiser HD219 headphones were used by judges to perceptually evaluate voice samples. To label these recordings raters used the Grade-Roughness-Breathiness (GRB) perceptual scale which is a modified version of the original Hirano’s GRBAS scale, posteriorly modified by Dejonckere et al., [6]. In order to improve intra- and inter-raters’ agreement two types of modifications were introduced in the rating procedure, i.e. the 0-3 points scale resolution was increased by adding subintervals to the standard 0-3 intervals, and judges were provided with a written protocol with explicit definitions about the subintervals boundaries. By this way judges could compensate for the potential instability that might occur in their internal representations due to the perceptual context influence [7]. Raters’ perceptual evaluations were simultaneously performed by means of connecting the Sennheiser HD219 headphones to a multi-channel headphone preamp Behringer HA4700 Powerplay Pro-XL. The Yin algorithm [8] was selected as initial front-end to identify voiced frames and extract their fundamental frequency. For the digital processing of voice signals some conventional acoustic parameters [6] were selected. To complete the analysis the Mel-Frequency Cepstral Coefficients (MFCC) were further calculated because they are based on the auditory model and they are thus closer to the auditory system response than conventional features. Results. In the perceptual evaluation excellent intra-raters agreement and very good inter-raters agreement were achieved. During the supervised machine learning stage some conventional features were found to attain unexpected low performance in the classification scheme selected. Mel Frequency Cepstral Coefficients were promising for assorting samples with normal or quasi-normal voice quality. Discussion and conclusions. Despite it is still small and unbalanced the present annotated data base of voice samples can provide a basis for the development of other databases and automatic classification tools. Other authors [9, 10, 11] also found that modeling the auditory non-linear response during signal processing can help develop objective measures that better correspond with perceptual data. However highly disordered voices classification remains to be a challenge for this set of features since they cannot be correctly assorted by either conventional variables or the auditory model based measures. Current results warrant further research in order to find out the usability of other types of voice samples and features for the automatic classification schemes. Different digital processing steps could be used to improve the classifiers performance. Additionally other types of classifiers could be taken into account in future studies. Acknowledgment. This work was funded by the Spanish Ministerio de Economía y Competitividad, Project No. TIN2013-47276-C6-2-R has been done in the Campus de Excelencia Internacional Andalucía Tech, Universidad de Málaga. References [1] Carding PN, Wilson JA, MacKenzie K, Deary IJ. Measuring voice outcomes: state of the science review. The Journal of Laryngology and Otology 2009;123,8:823-829. [2] Oates J. Auditory-perceptual evaluation of disordered voice quality: pros, cons and future directions. Folia Phoniatrica et Logopaedica 2009;61,1:49-56. [3] Maryn et al. Meta-analysis on acoustic voice quality measures. J Acoust Soc Am 2009; 126, 5: 2619-2634. [4] Vaz Freitas et al. Correlation Between Acoustic and Audio-Perceptual Measures. J Voice 2015;29,3:390.e1 [5] “Multi-Dimensional Voice Program (MDVP) Model 5105. Software Instruction Manual”, Kay PENTAX, A Division of PENTAX Medical Company, 2 Bridgewater Lane, Lincoln Park, NJ 07035-1488 USA, November 2007. [6] Dejonckere PH, Bradley P, Clemente P, Cornut G, Crevier-Buchman L, Friedrich G, Van De Heyning P, Remacle M, Woisard V. A basic protocol for functional assessment of voice pathology, especially for investigating the efficacy of (phonosurgical) treatments and evaluating new assessment techniques. Guideline elaborated by the Comm. on Phoniatrics of the European Laryngological Society (ELS). Eur Arch Otorhinolaryngol 2001;258:77–82. [7] Kreiman et al. Voice Quality Perception. J Speech Hear Res 1993;36:21-4 [8] De Cheveigné A, Kawahara H. YIN, a fundamental frequency estimator for speech and music. J. Acoust. Soc. Amer. 202; 111,4:1917. [9] Shrivastav et al. Measuring breathiness. J Acoust Soc Am 2003;114,4:2217-2224. [10] Saenz-Lechon et al. Automatic Assessment of voice quality according to the GRBAS scale. Eng Med Biol Soc Ann 2006;1:2478-2481. [11] Fredouille et al. Back-and-forth methodology for objective voice quality assessment: from/to expert knowledge to/from automatic classification of dysphonia. EURASIP J Appl Si Pr 2009.Campus de Excelencia Internacional Andalucía Tech, Universidad de Málaga. Ministerio de Economía y Competitividad, Projecto No. TIN2013-47276-C6-2-R

    Central nervous system commitment in Chagas disease

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    The involvement of the central nervous system (CNS) during human acute and chronic Chagas disease (CD) has been largely reported. Meningoencephalitis is a frequent finding during the acute infection, while during chronic phase the CNS involvement is often accompanied by behavioral and cognitive impairments. In the same vein, several studies have shown that rodents infected with Trypanosoma cruzi (T. cruzi) display behavior abnormalities, accompanied by brain inflammation, in situ production of pro-inflammatory cytokines and parasitism in diverse cerebral areas, with involvement of microglia, macrophages, astrocytes, and neurons. However, the mechanisms used by the parasite to reach the brain remain now largely unknown. Herein we discuss the evidence unravelling the CNS involvement and complexity of neuroimmune interactions that take place in acute and chronic CD. Also, we provide some clues to hypothesize brain infections routes in human and experimental acute CD following oral infection by T. cruzi, an infection route that became a major CD related public health issue in Brazil.Fil: Useche, Yerly. Fundación Oswaldo Cruz; BrasilFil: Perez, Ana Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; ArgentinaFil: de Meis, Juliana. Fundación Oswaldo Cruz; BrasilFil: Bonomo, Adriana. Fundación Oswaldo Cruz; BrasilFil: Savino, Wilson. Fundación Oswaldo Cruz; Brasi

    The Thymus in Chagas Disease: Molecular Interactions Involved in Abnormal T-Cell Migration and Differentiation

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    Chagas disease, caused by the protozoan parasite T. cruzi, is a prevalent parasitic disease in Latin America. Presently, it is spreading around the world by human migration, thus representing a new global health issue. Chronically infected individuals reveal a dissimilar disease progression: while nearly 60% remain without apparent disease for life, 30% develop life-threatening pathologies, such as chronic chagasic cardiomyopathy (CCC) or megaviscerae. Inflammation driven by parasite persistence seems to be involved in the pathophysiology of the disease. However, there is also evidence of the occurrence of autoimmune events, mainly caused by molecular mimicry and bystander activation. In experimental models of disease, is well-established that T. cruzi infects the thymus and causes locally profound structural and functional alterations. The hallmark is a massive loss of CD4+CD8+ double positive (DP) thymocytes, mainly triggered by increased levels of glucocorticoids, although other mechanisms seem to act simultaneously. Thymic epithelial cells (TEC) exhibited an increase in extracellular matrix deposition, which are related to thymocyte migratory alterations. Moreover, medullary TEC showed a decreased expression of AIRE and altered expression of microRNAs, which might be linked to a disrupted negative selection of the T-cell repertoire. Also, almost all stages of thymocyte development are altered, including an abnormal output of CD4−CD8− double negative (DN) and DP immature and mature cells, many of them carrying prohibited TCR-Vβ segments. Evidence has shown that DN and DP cells with an activated phenotype can be tracked in the blood of humans with chronic Chagas disease and also in the secondary lymphoid organs and heart of infected mice, raising new questions about the relevance of these populations in the pathogenesis of Chagas disease and their possible link with thymic alterations and an immunoendocrine imbalance. Here, we discuss diverse molecular mechanisms underlying thymic abnormalities occurring during T. cruzi infection and their link with CCC, which may contribute to the design of innovative strategies to control Chagas disease pathology.Fil: Perez, Ana Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; ArgentinaFil: de Meis, Juliana. Fundación Oswaldo Cruz; BrasilFil: Rodriguez Galan, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Savino, Wilson. Fundación Oswaldo Cruz; Brasi
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