1,720,990 research outputs found
Discovering Shape Classes using Tree Edit-Distance and Pairwise Clustering
This paper describes work aimed at the unsupervised learning of shape-classes from shock trees. We commence by considering how to compute the edit distance between weighted trees. We show how to transform the tree edit distance problem into a series of maximum weight clique problems, and show how to use relaxation labeling to find an approximate solution. This allows us to compute a set of pairwise distances between graph-structures. We show how the edit distances can be used to compute a matrix of pairwise affinities using χ² statistics. We present a maximum likelihood method for clustering the graphs by iteratively updating the elements of the affinity matrix. This involves interleaved steps for updating the affinity matrix using an eigendecomposition method and updating the cluster membership indicators. We illustrate the new tree clustering framework on shock-graphs extracted from the silhouettes of 2D shapes
Patch-Based Representation of Visual Speech
Visual information from a speaker's mouth region is known to\ud
improve automatic speech recognition robustness, especially in the presence of acoustic noise. To date, the vast majority of work in this field has viewed these visual features in a holistic manner, which may not take into account the various changes that occur within articulation (process of changing the shape of the vocal tract using the articulators, i.e lips and jaw). Motivated by the work being conducted in fields of audio-visual automatic speech\ud
recognition (AVASR) and face recognition using articulatory\ud
features (AFs) and patches respectively, we present a\ud
proof of concept paper which represents the mouth region as a ensemble of image patches. Our experiments show that by dealing with the mouth region in this manner, we are able to extract more speech information from the visual domain. For the task of visual-only speaker-independent isolated digit recognition, we were able to improve the relative word error rate by more than 23\% on the CUAVE audio-visual corpus
Going Beyond Counting First Authors in Author Co-citation Analysis
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
Variations on the Author
“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
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
Enhanced kernel-based tracking for monochromatic and thermographic video
In this paper, we present an enhanced kernel-based tracker for monochromatic and thermographic video. The technique presented here employs the image intensity and the Local Binary Pattern (LBP) to construct a two dimensional histogram representative of the grayscale values and the texture of the target under study. With the histogram at hand, we proceed to compute its power density function. The new location of the object is then determined making use of a mean-shift optimisation approach. We illustrate the performance of our method in both, thermographic and monochromatic footages and compare our results to an alternative.Quang Anh Nguyen, Robles-Kelly, A. and Chunhua She
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