1,720,960 research outputs found
Visual Navigation Using Sparse Optical Flow and Time-to-Transit
Full text linkDrawing inspiration from biology, we describe the way in which visual sensing with a monocular camera can provide a reliable signal for navigation of mobile robots. The work takes inspiration from the classic paper which described a behavioral strategy pursued by diving sea birds based on a visual cue called time-to-contact. A closely related concept of time-to-transit, tau, is defined, and it is shown that steering
laws based on monocular camera perceptions of tau can reliably steer a mobile vehicle. The contribution of the paper is two-fold. It provides a simple theory of robust vision-based steering control. It goes on to show how the theory guides the implementation of robust visual navigation using ROS-Gazebo simulations as well as deployment and experiments with a camera-equipped Jackal robot. As will be noted, there is an extensive literature on how animals use optical flow to guide their movements. The novelty of the work below is the introduction of the concepts of Eulerian optical flow and time-to-transit, tau and the demonstration that control laws based on the tau values associated with an aggregated set of features in the field of view can be used to reliably steer a laboratory robot
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
Memory in Motion: Exploring Leaky Integration of Time Surfaces for Event-based Eye-tracking
Full text linkAugmented and Virtual Reality (AR/VR) technologies are gaining popularity to improve healthcare professionals training, with precise eye tracking playing a crucial role in enhancing performance. However, these systems need to be both low-latency and low-power to operate in real-time scenarios on resource-constrained devices. Event-based cameras can be employed to address these requirements, as they offer energy-efficient, high temporal resolution data with minimal battery drain. However, their sparse data format necessitates specialized processing algorithms. In this work, we propose a data preprocessing technique that improves the performance of nonrecurrent Deep Neural Networks (DNNs) for pupil position estimation. With this approach, we integrate over time - with a leakage factor - multiple time surfaces of events, so that the input data is enriched with information from past events. Additionally, in order to better distinguish between recent and old information, we generate multiple memory channels characterized by different leakage/forgetting rates. These memory channels are fed to well-known non-recurrent neural estimators to predict the position of the pupil. As an example, by using time surfaces only and feeding them to a MobileNet-V3L model to track the pupil in DVS recordings, we achieve a P10 accuracy (Euclidean error lower than ten pixels) of 85.40%, whether by using memory channels we achieve a P10 accuracy of 94.37% with a negligible time overhead
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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