12,040 research outputs found

    Towards Automatic Speech Identification from Vocal Tract Shape Dynamics in Real-time MRI

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    Vocal tract configurations play a vital role in generating distinguishable speech sounds, by modulating the airflow and creating different resonant cavities in speech production. They contain abundant information that can be utilized to better understand the underlying speech production mechanism. As a step towards automatic mapping of vocal tract shape geometry to acoustics, this paper employs effective video action recognition techniques, like Long-term Recurrent Convolutional Networks (LRCN) models, to identify different vowel-consonant-vowel (VCV) sequences from dynamic shaping of the vocal tract. Such a model typically combines a CNN based deep hierarchical visual feature extractor with Recurrent Networks, that ideally makes the network spatio-temporally deep enough to learn the sequential dynamics of a short video clip for video classification tasks. We use a database consisting of 2D real-time MRI of vocal tract shaping during VCV utterances by 17 speakers. The comparative performances of this class of algorithms under various parameter settings and for various classification tasks are discussed. Interestingly, the results show a marked difference in the model performance in the context of speech classification with respect to generic sequence or video classification tasks.Comment: To appear in the INTERSPEECH 2018 Proceeding

    Postalveolar fricatives in Slavic languages as retroflexes

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    The present study poses the question on what phonetic and phonological grounds postalveolar fricatives in Polish can be analyzed as retroflex and whether postalveolar fricatives in other Slavic languages are retroflex as well. Velarization and incompatibility with front vowels are introduced as articulatory criteria for retroflexion, based on crosslinguistic data. According to these criteria, Polish and Russian have retroflex fricatives, whereas Bulgarian and Czech do not. In a phonological representation of these Slavic retroflexes, the necessity of perceptual features is shown. Lastly, it is illustrated that palatalization of retroflex fricatives both in Slavic languages and more generally causes a phonetic and phonological change to a non-retroflex sound

    A survey on mouth modeling and analysis for Sign Language recognition

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    © 2015 IEEE.Around 70 million Deaf worldwide use Sign Languages (SLs) as their native languages. At the same time, they have limited reading/writing skills in the spoken language. This puts them at a severe disadvantage in many contexts, including education, work, usage of computers and the Internet. Automatic Sign Language Recognition (ASLR) can support the Deaf in many ways, e.g. by enabling the development of systems for Human-Computer Interaction in SL and translation between sign and spoken language. Research in ASLR usually revolves around automatic understanding of manual signs. Recently, ASLR research community has started to appreciate the importance of non-manuals, since they are related to the lexical meaning of a sign, the syntax and the prosody. Nonmanuals include body and head pose, movement of the eyebrows and the eyes, as well as blinks and squints. Arguably, the mouth is one of the most involved parts of the face in non-manuals. Mouth actions related to ASLR can be either mouthings, i.e. visual syllables with the mouth while signing, or non-verbal mouth gestures. Both are very important in ASLR. In this paper, we present the first survey on mouth non-manuals in ASLR. We start by showing why mouth motion is important in SL and the relevant techniques that exist within ASLR. Since limited research has been conducted regarding automatic analysis of mouth motion in the context of ALSR, we proceed by surveying relevant techniques from the areas of automatic mouth expression and visual speech recognition which can be applied to the task. Finally, we conclude by presenting the challenges and potentials of automatic analysis of mouth motion in the context of ASLR

    Quantitative Comparison of Abundance Structures of Generalized Communities: From B-Cell Receptor Repertoires to Microbiomes

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    The \emph{community}, the assemblage of organisms co-existing in a given space and time, has the potential to become one of the unifying concepts of biology, especially with the advent of high-throughput sequencing experiments that reveal genetic diversity exhaustively. In this spirit we show that a tool from community ecology, the Rank Abundance Distribution (RAD), can be turned by the new MaxRank normalization method into a generic, expressive descriptor for quantitative comparison of communities in many areas of biology. To illustrate the versatility of the method, we analyze RADs from various \emph{generalized communities}, i.e.\ assemblages of genetically diverse cells or organisms, including human B cells, gut microbiomes under antibiotic treatment and of different ages and countries of origin, and other human and environmental microbial communities. We show that normalized RADs enable novel quantitative approaches that help to understand structures and dynamics of complex generalize communities

    Features For Automated Tongue Image Shape Classification

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    Inspection of the tongue is a key component in Traditional Chinese Medicine. Chinese medical practitioners diagnose the health status of a patient based on observation of the color, shape, and texture characteristics of the tongue. The condition of the tongue can objectively reflect the presence of certain diseases and aid in the differentiation of syndromes, prognosis of disease and establishment of treatment methods. Tongue shape is a very important feature in tongue diagnosis. A different tongue shape other than ellipse could indicate presence of certain pathologies. In this paper, we propose a novel set of features, based on shape geometry and polynomial equations, for automated recognition and classification of the shape of a tongue image using supervised machine learning techniques. We also present a novel method to correct the orientation/deflection of the tongue based on the symmetry of axis detection method. Experimental results obtained on a set of 303 tongue images demonstrate that the proposed method improves the current state of the art method. © 2012 IEEE

    Peramorphosis, an evolutionary developmental mechanism in neotropical bat skull diversity

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    Background The neotropical leaf‐nosed bats (Chiroptera, Phyllostomidae) are an ecologically diverse group of mammals with distinctive morphological adaptations associated with specialized modes of feeding. The dramatic skull shape changes between related species result from changes in the craniofacial development process, which brings into focus the nature of the underlying evolutionary developmental processes. Results In this study, we use three‐dimensional geometric morphometrics to describe, quantify, and compare morphological modifications unfolding during evolution and development of phyllostomid bats. We examine how changes in development of the cranium may contribute to the evolution of the bat craniofacial skeleton. Comparisons of ontogenetic trajectories to evolutionary trajectories reveal two separate evolutionary developmental growth processes contributing to modifications in skull morphogenesis: acceleration and hypermorphosis. Conclusion These findings are consistent with a role for peramorphosis, a form of heterochrony, in the evolution of bat dietary specialists

    Developmental changes and novelties in ceratophryid frogs

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    The Neotropical frog genera Ceratophrys, Chacophrys and Lepidobatrachus form the monophyletic family Ceratophryidae. Although in- and out-group relationships are not fully resolved, the monophyly of the three genera is well supported by both morphological and molecular data. Much is known about the morphology of the ceratophryids, but there is little comparative information on how modification of a common ancestral developmental pathway played a role in shaping their particular body plans. Herein, we review morphological variation during ceratophryid ontogeny in order to explore the role of development in their evolution. The ceratophryids are collectively characterized by rapid larval development with respect to other anurans, yet the three genera differ in their postmetamorphic growth rates to sexual maturity. Derived traits in the group can be divided into many homoplastic features that evolved in parallel with those of anurans with fossorial/burrowing behaviors in semiarid environments, and apomorphies. Morphological novelties have evolved in their feeding mechanism, which makes them capable of feeding on exceptional large prey. Lepidobatrachus is unusual in having reduced the ecomorphological differences between its larvae and adults. As a result, both the larvae and the frog are similarly able to capture large prey underwater. Some unique features in Lepidobatrachus are differentiated in the tadpole and then exaggerated in the adult (e.g., the posterior displaced jaw articulation) in a manner unobserved in any other anurans.Fil: Fabrezi, Marissa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Quinzio, Silvia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Goldberg, Francisco Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Cruz, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Chuliver Pereyra, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Wassersug, Richard J.. Dalhousie University Halifax; Canad

    Assessing the Complexity of a Recovered Design and its Potential Redesign Alternatives

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    Organised by: Cranfield UniversityReverse engineering techniques are applied to generate a part model where there is no existing documentation or it is no longer up to date. To facilitate the reverse engineering tasks, a modular, multiperspective design recovery framework has been developed. An evaluation of the product and feature complexity characteristics can readily be extracted from the design recovery framework by using a modification of a rapid complexity assessment tool. The results from this tool provide insight with respect to the original design and assists with the evaluation of potential alternatives and risks, as illustrated by the case study.Mori Seiki – The Machine Tool Compan

    A survey of instabilities within centrifugal pumps and concepts for improving the flow range of pumps in rocket engines

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    Design features and concepts that have primary influence on the stable operating flow range of propellant-feed centrifugal turbopumps in a rocket engine are discussed. One of the throttling limitations of a pump-fed rocket engine is the stable operating range of the pump. Several varieties of pump hydraulic instabilities are mentioned. Some pump design criteria are summarized and a qualitative correlation of key parameters to pump stall and surge are referenced. Some of the design criteria were taken from the literature on high pressure ratio centrifugal compressors. Therefore, these have yet to be validated for extending the stable operating flow range of high-head pumps. Casing treatment devices, dynamic fluid-damping plenums, backflow-stabilizing vanes and flow-reinjection techniques are summarized. A planned program was undertaken at LeRC to validate these concepts. Technologies developed by this program will be available for the design of turbopumps for advanced space rocket engines for use by NASA in future space missions where throttling is essential
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