1,721,120 research outputs found

    Onset based audio segmentation for the Irish tin whistle

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    A technique for segmenting tin whistle audio signals according to the position of the note onsets is presented. This method focuses on the characteristics of the tin whistle within Irish traditional music, customising a time-frequency based representation for detecting the instant when a note starts and releases. Musical ornamentation, such as cuts and strikes, are very common in Irish traditional music and are played during the onset stage. Taking advantage of this musical feature, a novel technique for improving the onset time estimation is also presented

    Single-note Ornementation Transcription for the Irish Tin Whislte based on Onset Detection

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    Ornamentation plays a very important role in Irish Traditional music, giving more expression to the music by altering or embellishing small pieces of a melody. Single-note ornamentation, such as cuts and strikes, are the most common type in Irish Traditional music and are played by articulating the note pitch during the onset stage. A technique for transcribing single note ornamentation for the tin whistle based on onset detection is presented. This method focuses on the characteristics of the tin whistle within Irish traditional music, customising a time-frequency based representation for detecting the instant when new notes are played using single-note ornamentation start and release

    Drum Source Separation using Percussive Feature Detection and Spectral Modulation

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    We present a method for the separation and resynthesis of drum sources from single channel polyphonic mixtures. The frequency domain technique involves identifying the presence of a drum using a novel percussive feature detection function, after which the short-time magnitude spectrum is estimated and scaled according to an estimated time-amplitude function derived from the percussive measure. In addition to producing high quality separation results, the method we describe is also a useful pre-process for drum transcription techniques such as Prior Subspace Analysis in the presence of pitched instruments

    Independent subspace analysis using locally linear embedding

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    While Independent Subspace Analysis provides a means of blindly separating sound sources from a single channel signal, it does have a number of problems. In particular the amount of information required for separation of sources varies with the signal. This is as a result of the variance-based nature of Principal Component Analysis, which is used for dimensional reduction in the Independent Subspace Analysis algorithm. In an attempt to overcome this problem the use of a non-variance based dimensional reduction method, Locally Linear Embedding, is proposed. Locally Linear Embedding is a geometry based dimensional reduction technique. The use of this approach is demonstrated by its application to single channel source separation, and its merits discussed. 1. INDEPENDENT SUBSPACE ANALYSIS Independent Subspace Analysis (ISA) provides a means of blind sound source separation from single channel mixtures [1]. ISA represents sound sources as low dimensional subspaces in the time-frequency plane. The single channel mixture is assumed to result from the sum of a number of unknown independent sources. The single channel mixture is converted to a timefrequency representation such as a spectrogram by means of carrying out a Short Time Fourier Transform on the signal and retaining only the magnitude values. The resulting spectrogram is then assumed to result from the superposition of l unknown independent spectrograms. Further each independent spectrogram is assumed to be represented as the outer product of an invariant frequency basis function fj and a corresponding time basis function tj. This yields

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Onset Detection and Music Transcription for the Irish Tin Whistle

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    Abstract-- A technique for detecting tin whistle note onsets and transcribing the corresponding pitches is presented. This method focuses on the characteristics of the tin whistle within Irish traditional music, customising a time-frequency based representation for extracting the instant when a note starts and the music notation. Results show that the presented approach improves upon the existing energy based approaches in terms of the percentage of correct detections. __________________________________________________________________________________________

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods
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