1,721,065 research outputs found
Learning to maintain upright posture: what can be learnt using adaptive neural networks models?
No full textHuman upright posture is an unstable position: Continuous activation of postural muscles is required
to avoid falling down. This is the output of a complex control system that monitors a very large
number of inputs, related to the orientation of the body segments, to produce an adequate output as
muscle activation. Complexity arises because of the very large number of correlated inputs and outputs:
The finite contraction and release time of muscles and the neural control loop delays make the
problem even more difficult. Nevertheless, upright posture is a capability that is learned in the first
year of life. Here, the learning process is investigated by using a neural network model for the controller
and the reinforcement learning paradigm. To this end, after creating a mechanically realistic digital
human body, a feedback postural controller is defined, which outputs a set of joint torques as a function
of orientation and rotation speed of the body segments. The controller is made up of a neural network,
whose “synaptic weights” are determined through trial-and-error (failure in maintaining upright
posture) by using a reinforcement learning strategy. No desired control action is specified nor particular
structure given to the controller. The results show that the anatomical arrangement of the skeleton
is sufficient to shape a postural control, robust against torque perturbations and noise, and flexible
enough to adapt to changes in the body model in a short time. Moreover, the learned kinematics
closely resembles the data reported in the literature; it emerges from the interaction with the environment,
only through trial-and-error. Overall, the results suggest that anatomical arrangement of the
body segments may play a major role in shaping human motor control
Capolavori svelati. La collezione Chiomenti Vassalli a Calvi dell'Umbria
No full textCatalogo con schede storico artistiche dei dipinti della Collazione Chiomenti Vassalli ospitata nel Monastero delle Orsoline a Calvi dell'Umbria. La collezione racchiude capolavori del '600 romano e centro italiano
Anna Carotti, Gli affreschi della Grotta delle Fornelle a Calvi Vecchia
No full textAnna Carotti, Gli affreschi della Grotta delle Fornelle a Calvi Vecchia. In: Revue des études byzantines, tome 35, 1977. p. 319
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
Anna Carotti, Gli affreschi della Grotta delle Fornelle a Calvi Vecchia
No full textAnna Carotti, Gli affreschi della Grotta delle Fornelle a Calvi Vecchia. In: Revue des études byzantines, tome 35, 1977. p. 319
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
Anna Carotti. — Gli affreschi della Grotta delle Fornelle a Calvi Vecchia, 1974.
No full textNikolajević Ivanka. Anna Carotti. — Gli affreschi della Grotta delle Fornelle a Calvi Vecchia, 1974.. In: Cahiers de civilisation médiévale, 19e année (n°75), Juillet-septembre 1976. pp. 278-280
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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