1,721,038 research outputs found
Adaptive instantiation of service workflows using a chemical approach
No full textService oriented technologies allow Service Based Applications (SBAs) to be easily built by composing independent services available in a network and provided by many actors under conditions that may change in time. Therefore services need to be dynamically selected and composed when an SBA is required along with parameters representing the service delivery conditions. In this paper we propose to use a chemical computational approach to model the process of selecting the required service functionalities with the required conditions as an evolving and always running middleware mechanism. The chemical evolving behaviour of the middleware allows to take into account environmental changes coming from both the providers and users side. © 2011 Springer-Verlag Berlin Heidelberg
Using chemical reactions to model service composition
No full textInternet is evolving from a network of computers and information into a network of services allowing applications to be built by selecting services and composing them in a loosely coupled manner. These Service Based Applications (SBA) are composed of a number of possibly independent services that are provided by many actors under different conditions (like price, time to deliver, and so on). Service provision conditions may change in time depending on provider policies or other environmental changes, so it is necessary to organize compositions of services on demand in response to dynamic requirements and circumstances. In this paper we propose to use a chemical computational model to address this problem by decoupling the process of finding services composing an SBA requested by a user, from their actual enactment. An SBA request is described in terms of an abstract workflow where only service functionalities of the single components and their execution order (i.e. the application control flow) are specified, along with parameters representing the conditions under which the user expects the application to be delivered. The proposed approach allows to model the process of instantiating the required functionalities with actual service implementations as an evolving and always running middleware mechanism that can take into account the current state of the context when the composition is required. Furthermore, the evolutionary nature of the chemical system provides a form of adaptation since once compositions of services are computed with the available services, new compositions can be computed as soon as new services become available or the conditions of existing ones change. © 2010 ACM
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Pharmacological modulation of P2X4 in inflammatory bowel diseases: the way towards novel therapeutics?
No full textInflammatory bowel diseases (IBDs) are a group of idiopathic, chronic, relapsing, inflammatory conditions, which include ulcerative colitis (UC) and Crohn’s disease (CD). These disorders are characterised by intestinal symptoms associated with chronic inflammation of the intestinal mucosa, such as gut dysmotility and visceral pain. Currently, the pharmacological management of IBD patients is far from satisfactory in terms of efficacy and safety, thus spurring the interest of the scientific community to identify novel molecular targets for the management of these disorders. According to recent research, it appears that P2 purinergic receptors, which can regulate the host’s response to inflammation, have been identified as potential targets for the treatment of IBDs. In particular, among P2 receptors, the P2X4 receptor subtype has recently captured the attention of the research community owing to its role in shaping immune/inflammatory responses. Based on this evidence, the present review has been conceived to provide a critical appraisal of the available knowledge about the role of P2X4R subtype in the pathophysiological mechanisms underlying IBDs, pointing out its potential as therapeutic target to develop innovative therapeutic strategies aimed at counteracting the inflammatory process, gut dysmotility and visceral hypersensitivity associated with these disorders
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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