636 research outputs found
Cardiovascular magnetic resonance demonstration of the spectrum of morphological phenotypes and patterns of myocardial scarring in Anderson-Fabry disease
published_or_final_versio
Assessment of New Hub-and-spoke and Point-to-point Airline Network Configurations
This paper aims to provide new measures of airline network configuration with a view to analyse effectively the complexity of modern carriers' network design. It studies network configurations in the airline sector by taking into account both spatial and temporal dimensions. The spatial dimension is measured by using both the Gini index and the Freeman index, which originate from social science research. The temporal dimension is measured by the connectivity ratio, i.e. the share of indirect connections over the total number of connections. According to these indicators, the configuration of the largest full-service carriers and the largest low-cost carriers in Europe is investigated. The results show that the temporal dimension provides a clear distinction between full-service carriers and low-cost carriers; while the spatial dimension appears useful when identifying the peculiarities within groups
New apparatus for DTA at 2000 bar: thermodynamic studies on Au, Ag, Al and HTSC oxides
A new DTA (Differential Thermal Analysis) device was designed and installed
in a Hot Isostatic Pressure (HIP) furnace in order to perform high-pressure
thermodynamic investigations up to 2 kbar and 1200C. Thermal analysis can be
carried out in inert or oxidising atmosphere up to p(O2) = 400 bar. The
calibration of the DTA apparatus under pressure was successfully performed
using the melting temperature (Tm) of pure metals (Au, Ag and Al) as standard
calibration references. The thermal properties of these metals have been
studied under pressure. The values of DV (volume variation between liquid and
solid at Tm), ROsm (density of the solid at Tm) and ALPHAm (linear thermal
expansion coefficient at Tm) have been extracted. A very good agreement was
found with the existing literature and new data were added. This HP-DTA
apparatus is very useful for studying the thermodynamics of those systems where
one or more volatile elements are present, such as high TC superconducting
oxides. DTA measurements have been performed on Bi,Pb(2223) tapes up to 2 kbar
under reduced oxygen partial pressure (p(O2) = 0.07 bar). The reaction leading
to the formation of the 2223 phase was found to occur at higher temperatures
when applying pressure: the reaction DTA peak shifted by 49C at 2 kbar compared
to the reaction at 1 bar. This temperature shift is due to the higher stability
of the Pb-rich precursor phases under pressure, as the high isostatic pressure
prevents Pb from evaporating.Comment: 6 figures, 3 tables, Thermodynamics, Thermal property, Bi-2223,
fundamental valu
Association between co-authorship network and scientific productivity and impact indicators in academic medical research centers: A case study in Iran
<p>Abstract</p> <p>Background</p> <p>We aimed to examine the co-authorship networks in three successful Iranian academic research centers, in order to find the association between the scientific productivity and impact indicators with network features in a case study.</p> <p>Methods</p> <p>We searched for English articles of the three research centers. We drew co-authorship maps of each center and calculated social network measures.</p> <p>Results</p> <p>The collaboration networks in centers shared many structural features, including a "star-like" pattern of relations. Centers with more successful scientific profile showed denser and more cooperative networks. Key figures in each center were interviewed for their understandings of the reasons for the emergence of these patterns.</p> <p>Conclusion</p> <p>Star shape network structure and dependency on a single big member is a common feature observed in our case study. Scientific output measures correlate with the network structure of research centers. Network analysis seems a useful method to explore the subtle scientific contexts in research organizations.</p
Investigating Student Communities with Network Analysis of Interactions in a Physics Learning Center
Developing a sense of community among students is one of the three pillars of
an overall reform effort to increase participation in physics, and the sciences
more broadly, at Florida International University. The emergence of a research
and learning community, embedded within a course reform effort, has contributed
to increased recruitment and retention of physics majors. Finn and Rock [1]
link the academic and social integration of students to increased rates of
retention. We utilize social network analysis to quantify interactions in
Florida International University's Physics Learning Center (PLC) that support
the development of academic and social integration,. The tools of social
network analysis allow us to visualize and quantify student interactions, and
characterize the roles of students within a social network. After providing a
brief introduction to social network analysis, we use sequential multiple
regression modeling to evaluate factors which contribute to participation in
the learning community. Results of the sequential multiple regression indicate
that the PLC learning community is an equitable environment as we find that
gender and ethnicity are not significant predictors of participation in the
PLC. We find that providing students space for collaboration provides a vital
element in the formation of supportive learning community.Comment: 14 pages, 3 tables, 4 figure
Enhancing the Social Capital of Learning Communities by Using an Ad Hoc Transient Communities Service
Fetter, S., Berlanga, A. J., & Sloep, P. B. (2009). Enhancing the Social Capital of Learning Communities by Using an Ad Hoc Transient Communities Service. In M. Spaniol, Q. Li, R. Klamma & R. W. H. Lau (Eds.), Proceedings of the 8th International Conference Advances in Web-based Learning - ICWL 2009 (pp. 150-157). August, 19-21, 2009, Aachen, Germany. Lecture Notes in Computer Science 5686; Berlin, Heidelberg: Springer-Verlag.In online learning, communities can help to enhance learning. However, because of the dynamic nature of communities, attaining and sustaining these communities can be difficult. One aspect that has an influence on, and is influenced by these dynamics is the social capital of a community. Features of social capital are the social network structure, the sense of belonging and, the support received and provided. It is hypothesized that these features can be improved by using Ad Hoc Transient Communities (AHTCs). Through an AHTC learners are brought together for a specific, learning-related goal (âad hocâ) and for only a limited amount of time (âtransienceâ). To test whether the use of AHTCs has a positive influence on the social capital, a learner support service which enables the use of AHTCs is proposed. Furthermore, requirements, pre-requisites, and future research are discussed.The work on this publication has been sponsored by the TENCompetence Integrated Project that is funded by the European Commission's 6th Framework Programme, priority IST/Technology Enhanced Learning. Contract 027087 [http://www.tencompetence.org
Experience of developing Twitter-based communities of practice in higher education
This article presents the results of a case study of the use of a microblogging tool by a university academic to increase their knowledge and experience of social media for educational purposes. The academic had the role of digital steward in a university and attempted to use microblogging (Twitter) to increase professional contacts within the framework of a community of practice. Several types of data were collected and analysed. These included the structure of the network arising from the links formed with others by microblogging, the similarity of stated interests between the academic and others in the network, and the contents of postings such as their external references. It was found that a personal network had been established, with some of the characteristics of a community of practice. The activity demonstrated the utility of social media in supporting the professional development of academic staff using technology
Self-Organizing Networks in Complex Infrastructure Projects
While significant importance is given to establishing formal organizational and contractual hierarchies, existing project management techniques neglect the management of self-organizing networks in large-infrastructure projects. We offer a case-specific illustration of self-organization using network theory as an investigative lens. The findings have shown that these networks exhibit a high degree of sparseness, short path lengths, and clustering in dense âfunctionalâ communities around highly connected actors, thus demonstrating the small-world topology observed in diverse real-world self-organized networks. The study underlines the need for these non-contractual functions and roles to be identified and sponsored, allowing the self-organizing network the space and capacity to evolve
A coherent graph-based semantic clustering and summarization approach for biomedical literature and a new summarization evaluation method
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