1,720,966 research outputs found
Speech intelligibility in virtual environments simulating an asymmetric directional microphone configuration
No full textThe benefit of directional processing and binaural listening in terms of speech intelligibility for frontal sound sources has been well documented in recent and past studies. Nevertheless, only the 20% of the situations in real life present a speaker located exactly in the frontal position. Different attempt have been done so far in order to allow, manually or automatically, a change in the directional pattern of the hearing aid, but the results of these studies are far from being satisfying. The purpose of this study is to explore the advantages brought by the asymmetric directional microphone configuration of hearing aids in terms of speech intelligibility for frontal, lateral and rear sound sources in noisy environments, and in terms of the quality of the "spatial perception" of the surrounding sound-scape. Through a 3D Ambisonic virtual environment manipulation, the presence of two microphones (the two hearing aids) is simulated in a noisy environment with a speech sound source. The listeners are presented with the signal recorded from the two simulated microphones, calibrated with symmetrical and asymmetrical directional patterns, and played through a pair of headphones. The speech intelligibility is measured for all the directional microphones configurations and for all the speech sound source positions
Eyes-free exploration of shapes with invisible puzzle
No full textRecent contributions proposed sonification techniques to allow people with visual impairment or blindness to extract information from images on touchscreen devices. In this contribution we introduce Invisible Puzzle Game, an application that is aimed at performing an instrumented remote evaluation of these sonification techniques. The aim is to reach a wide audience of both sighted and visually impaired users and to engage them, thanks to game elements, in playing over time, so that it is possible to evaluate how the performance of each sonification technique is affected by practice
Sonification of guidance data during road crossing for people with visual impairments or blindness
Full text linkIn the last years several solutions were proposed to support people with visual impairments or blindness during road crossing. These solutions focus on computer vision techniques for recognizing pedestrian crosswalks and computing their relative position from the user. Instead, this contribution addresses a different problem; the design of an auditory interface that can effectively guide the user during road crossing. Two original auditory guiding modes based on data sonification are presented and compared with a guiding mode based on speech messages.Experimental evaluation shows that there is no guiding mode that is best suited for all test subjects. The average time to align and cross is not significantly different among the three guiding modes, and test subjects distribute their preferences for the best guiding mode almost uniformly among the three solutions. From the experiments it also emerges that higher effort is necessary for decoding the sonified instructions if compared to the speech instructions, and that test subjects require frequent 'hints' (in the form of speech messages). Despite this, more than 2/3 of test subjects prefer one of the two guiding modes based on sonification. There are two main reasons for this: firstly, with speech messages it is harder to hear the sound of the environment, and secondly sonified messages convey information about the "quantity" of the expected movement
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Full text linkWe 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
On the evaluation of novel sonification techniques for non visual shape exploration
Full text linkThere are several situations in which a person with visual impairment or blindness needs to extract infor-
mation from an image. For example, graphical representations are often used in education, in particular in
STEM subjects. In this contribution we propose a set of 6 soni cation techniques to support individuals
with visual impairment or blindness in recognizing shapes on touchscreen devices. These techniques are
compared among themselves and with 2 other soni cation techniques already proposed in the literature.
Using
Invisible Puzzle
, a mobile application which allows to conduct non-supervised evaluation sessions, we
conducted tests with 49 subjects with visual impairment and blindness, and 178 sighted subjects. All sub-
jects involved in the process successfully completed the evaluation session, showing high level of engagement,
demonstrating therefore the e ectiveness of the evaluation procedure. Results give interesting insights into
the di erences among the soni cation techniques and, most importantly, show that after a short training
subjects are able to successfully identify several di erent shapes
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