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161.
Sebastian Weise Paul Coulton Mike Chiasson 《Computer Supported Cooperative Work (CSCW)》2017,26(4-6):927-958
Adapting and changing the systems and technologies involved in civic engagement with local government is among the key challenges of collaborative technologies for political participation. In such contexts, both existing sets of technologies and ingrained, often formalised practices, the ‘rules of the game’, constrain any opportunity for intervention. Additionally, ‘civic’ and expert groups with conflicting agendas and divergent demands on public choices assert their influence in these transformation programmes. The article argues that established methods in collaborative systems design have thus far overlooked the role of recurring actions involved in public participation as well as the formal rules and ingrained practices that construct them. Yet, such patterns present a valuable resource for design interventions. Thus, based on an institutional approach, the article outlines a methodology for requirement gathering by mapping the relations of actors, software and their use along identifiable action situations. The method called for a dialogue between socio-technical-spatial contexts of public service and specific actions taking place within it. Drawing on a case of organising civic engagement in urban planning, the article discusses how to find and trace existing practices across social settings, information technologies and material contexts where engagements take place. The approach underscores the existing institutional contexts in inspiring, opening and constraining the opportunities to support ‘civics’. 相似文献
162.
Hypermedia has for some time now been proposed as an adjunct to printed material within the educational process. However, creating a highly interconnected hypermedia network is complex and time consuming, with overviews of the content and structure of the information seemingly essential in order to avoid the disorientation and cognitive overload problems often described.This paper describes an environment designed to remove much of the burden of creating such support facilities, allowing the teacher to concentrate on the content and structure of the information presented. 相似文献
163.
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165.
Sam Fletcher Mike J. S. Lowe Madis Ratassepp Colin Brett 《Journal of Nondestructive Evaluation》2012,31(1):56-64
The implementation of synthetic guided wave focusing to locate axially aligned defects in pipes has been investigated. Results
from both finite element computer models and experiments on real pipes are presented and the data show good agreement. Focusing
is necessary to improve the reflection coefficient from axially aligned defects, as the signals are very weak. The Common
Source Method (CSM) of synthetic focusing has been applied which makes it possible to apply focusing via post processing to
previously collected data. The dependence of reflection coefficient on crack length was measured for both through thickness
and part depth axially aligned defects, at a range of frequencies, using the torsional guided wave family. The results show
that the reflection coefficient is approximately doubled when focusing is employed, compared to the sensitivity for unfocused
fundamental torsional waves. However the sensitivity is still very low, so in practise this approach could only be used to
find severe defects. 相似文献
166.
Mike Thelwall 《Scientometrics》2012,92(2):429-441
In theory, the web has the potential to provide information about the wider impact of academic research, beyond traditional scholarly impact. This is because the web can reflect non-scholarly uses of research, such as in online government documents, press coverage or public discussions. Nevertheless, there are practical problems with creating metrics for journals based on web data: principally that most such metrics should be easy for journal editors or publishers to manipulate. Nevertheless, two alternatives seem to have both promise and value: citations derived from digitised books and download counts for journals within specific delivery platforms. 相似文献
167.
Benjamin A. Hall Ethan Jackson Alex Hajnal Jasmin Fisher 《Journal of the Royal Society Interface》2014,11(98)
Caenorhabditis elegans vulval development is a paradigm system for understanding cell differentiation in the process of organogenesis. Through temporal and spatial controls, the fate pattern of six cells is determined by the competition of the LET-23 and the Notch signalling pathways. Modelling cell fate determination in vulval development using state-based models, coupled with formal analysis techniques, has been established as a powerful approach in predicting the outcome of combinations of mutations. However, computing the outcomes of complex and highly concurrent models can become prohibitive. Here, we show how logic programs derived from state machines describing the differentiation of C. elegans vulval precursor cells can increase the speed of prediction by four orders of magnitude relative to previous approaches. Moreover, this increase in speed allows us to infer, or ‘retrodict’, compatible genomes from cell fate patterns. We exploit this technique to predict highly variable cell fate patterns resulting from dig-1 reduced-function mutations and let-23 mosaics. In addition to the new insights offered, we propose our technique as a platform for aiding the design and analysis of experimental data. 相似文献
168.
Béatrice Fuster Deborah Houssin-Agbomson Simon Jallais Elena Vyazmina Guy Dang-Nhu Gilles Bernard-Michel Mike Kuznetsov Vladimir Molkov Boris Chernyavskiy Volodymyr Shentsov Dmitry Makarov Randy Dey Philip Hooker Daniele Baraldi Evelyn Weidner Daniele Melideo Valerio Palmisano Alexandros Venetsanos Jan Der Kinderen 《International Journal of Hydrogen Energy》2017,42(11):7600-7607
Hydrogen energy applications often require that systems are used indoors (e.g., industrial trucks for materials handling in a warehouse facility, fuel cells located in a room, or hydrogen stored and distributed from a gas cabinet). It may also be necessary or desirable to locate some hydrogen system components/equipment inside indoor or outdoor enclosures for security or safety reasons, to isolate them from the end-user and the public, or from weather conditions.Using of hydrogen in confined environments requires detailed assessments of hazards and associated risks, including potential risk prevention and mitigation features. The release of hydrogen can potentially lead to the accumulation of hydrogen and the formation of a flammable hydrogen-air mixture, or can result in jet-fires. Within Hyindoor European Project, carried out for the EU Fuel Cells and Hydrogen Joint Undertaking safety design guidelines and engineering tools have been developed to prevent and mitigate hazardous consequences of hydrogen release in confined environments. Three main areas are considered: Hydrogen release conditions and accumulation, vented deflagrations, jet fires and including under-ventilated flame regimes (e.g., extinguishment or oscillating flames and steady burns). Potential RCS recommendations are also identified. 相似文献
169.
Many webometric studies have used hyperlinks to investigate links to or between specific collections of websites to estimate their impact or identify connectivity patterns. Whilst major commercial search engines have previously been used to identify hyperlinks for these purposes, their hyperlink search facilities have now been shut down. In response, a range of alternative sources of link data have been suggested, but all have limitations. This article introduces a new type of link that can be identified from commercial search engines, linked title mentions. These can be found by querying title mentions in a search engine and then removing those not associated with a relevant hyperlink. Results of a proof of concept test on 51 U.S. library and information science schools and four other sets of schools suggest that linked title mentions may tend to give better results than title mentions in some cases when used for site inlinks but may not always be an improvement on URL citations. For links between or co-inlinks to specified pairs of academic websites, linked title mentions do not generally provide an improvement over title mentions, but they do over URL citations in some cases. Linked title mentions may also be useful for sets of non-academic websites when the alternatives give too few or misleading results. 相似文献
170.
Adam J. Hall Michael J. Chappell John A.D. Aston Stephen A. Ward 《Computer methods and programs in biomedicine》2014
A four compartment mechanistic mathematical model is developed for the pharmacokinetics of the commonly used anti-malarial drug artesunate and its principle metabolite dihydroartemisinin following oral administration of artesunate. The model is structurally unidentifiable unless additional constraints are imposed. Combinations of mechanistically derived constraints are considered to assess their effects on structural identifiability and on model fits. Certain combinations of the constraints give rise to locally or globally identifiable model structures. 相似文献