1,720,995 research outputs found
On the Causal Description of Interactions in Physically Distributed Systems
No full textThe description of distributed activities is formally approached. A formalism is introduced for the description of cause-effect relationships among states on distinct components. Three orthogonal operators are defined to describe the evolution of physically distributed systems. An abstraction operator is defined to derive a description based on distributed activities from the description based on centralized components. Only for purpose of "normalization", some categorial vocabulary has been used. For the complete comprehension of this report it is enough to know little more than the definition of category and functor. The material contained in this report is subject to continued revision and update. Although carefully self contained, it is not complete, as its concern is a research in progress. The reader interested in knowing about the development of this work may ask for updated documentation to the author at the following address: Dipartimento di Informatica Corso Italia N. 40 5610..
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
The Wandering Token: Congestion Avoidance of a Shared Resource
No full textIn a distributed system where scalability is an issue, like in a GRID [4], the problem of enforcing mutual exclusion often arises in a soft form: the infrequent failure of the mutual exclusion predicate is tolerated, without compromising the consistent operation of the overall system. For instance this occurs when the operation subject to mutual exclusion requires massive use of a shared resource. We introduce a scalable soft mutual exclusion algorithm, based on token passing: one distinguished feature of our algorithm is that instead of introducing an overlay topology we adopt a random walk approach. The consistency of our proposal is evaluated by simulation, and we exemplify its use in the coordination of large data transfers in a backbone based network
The Wandering Token: Congestion Avoidance of a Shared Resource
No full textIn a distributed system where scalability is an issue, like in a GRID, the problem of enforcing mutual exclusion often arises in a soft form: the infrequent failure of the mutual exclusion predicate is tolerated, without compromising the consistent operation of the overall system. For instance this occurs when the operation subject to mutual exclusion requires massive use of a shared resource. We introduce a scalable soft mutual exclusion algorithm, based on token passing: one distinguished feature of our algorithm is that instead of introducing an overlay topology we adopt a random walk approach. The consistency of our proposal is evaluated by simulation, and we exemplify its use in the coordination of large data transfers in a backbone based network
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
On-line Remote EKG as a Web Service
Full text linkA 3-leads, non-diagnostic EKG has a role in emergency rescue and homecare. In
this paper we introduce the design and a prototype of a service, provided to a
doctor and a patient, for the on-line remote visualization of patient's 3-leads
EKG. The architecture is based on the HTTP protocol, using commercial
off-the-shelf devices to implement the sensor on patient's side, a browser on a
laptop PC on the doctor's side as viewer, and a cloud container to connect the
two using Websockets. A prototype is built to evaluate signal latency, power
consumption of the patient side device, and the quality of the rendering. After
some experiments, latency is measured below , and power consumption is
estimated in the 2A*3.3V range; visualization is comparable to commercial,
non-diagnostic products. The prototype patient device is portable, and can be
operated using rechargeable battery packs. Its cost is below 100$, and all the
required equipment is commercially available. The architecture is ready for on
field evaluation, and we indicate how to improve power consumption while
reducing cost
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