1,720,963 research outputs found
Comparative Analysis of Isotropy Indices in RR and RRP Arms
No full textIn this paper isotropy and manipulability in RR dyads and RRP arms are analyzed and the solutions are obtained in algebraic symbolic forms. Such analysis is performed by means of two different methods: the classical approach based on the condition number and the Lie product. Although both the methods are known since decades, an accurate comparison of the two approaches has never been presented in literature. In particular, the geometrical interpretation of the Lie Product allows to appreciate some interesting differences between the two methods
Direct Coupling of Robotic Hands or Prostheses with the Radius Ulna Complex
No full textA new method of mechanically connecting artificial or robotic hands to the human arm is herein described. The idea is based on techniques which make use of fracture fixation devices, very well known in orthopedics. The presented connecting system consists in a real 3 DOF (w.r.t. the humerus) mechanism that has two end plates which are fixed directly, one on the radius, on the ulna the other. Since the system is a new concept project, no data exists about its reliability. Therefore, in the paper, a feasibility study on the most delicate components is described. In particular, FEA has been performed on the screws and on the bone-nut-screws, and some experimental tests in vitro have been made on a pig rib
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
A Comprehensive Evaluation of the Efficiency of an Integrated Biogas, Trigen and Greenhouse Plant, using Digraph Theory
No full textThis paper describes how directed graphs (digraphs) have been used for evaluating the total efficiency of a complex Plant that has been designed for the combined production of food, heat, cooling, and electrical energy. This task required three basic activities. Firstly, the overall plant scheme was studied in detail in order to identify the elementary blocks, each one having its own efficiency value. Each block corresponded to a single node of the digraph. Secondly, the system had to be considered as a whole. The development of the global scheme required the identification of all the directed arcs that were corresponding to the energy flows. Finally, a new algorithm for the evaluation of the overall efficiency was applied to the resultant digraph. This method allowed us to obtain the solution in algebraic symbolic form, automatically, provided that the digraph arc list was supplied to the developed PC code, together with the flow repartitions. The algorithm is quite robust and could also be used in systems with flow recirculation
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
Construction and Experimental Simulation of a Tethered MEMS-Based 3 DOF Silicon Micro Robot
No full textAn experimental campaign has been completed over a flexible manipulator which has been built in Expanded PVC by means of laser cutting. The geometry of such compliant mechanism has been developed on the basis of a new flexural hinge design concept. This flexible mechanism has also the same geometry of a MEMS based 3 DOF (degrees of freedom) compliant micro robot, which has been constructed in silicon by means of standard micro lithography and other MEMS Techniques. The flexible laser cut mechanism has dimensions one order of magnitude greater than the silicon MEMS micro manipulator. As a matter of fact, the laser cut flexible mechanism has a maximum overall size equal to about 80 mm and represents a scaled model for the MEMS based silicon micro robot, which has typical overall size down to 3 mm. The construction of the scaled mechanism has allowed to make easier the experimental campaign. The hardware is composed of many actuators and sensors, in particular by a micro actuator and a web cam, for the digital acquisition of the mechanism motion. The software has been independently developed, by the research group, in LabVIEW diagram block environment and MatLab programming language. The experimental campaigns have been designed to test the functionality of the system and the accuracy of the pseudo-rigid-body models
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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