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31.
Zuckerman: Scientist Extraordinary by Bernard Donovan BioScientifica, Bristol, 2005, 555pp. ISBN 1‐901978249 £24.95 Negotiating licences for digital resources by Fiona Durrant Facet Publishing, 2006, ISBN 1 85604 586 2 Metadata for Information Management and Retrieval By David Haynes Facet Publishing, 2004, ISBN 1 85604 4890 相似文献
32.
Analysis of the urban/rural broadband divide in Canada: Using GIS in planning terrestrial wireless deployment 总被引:3,自引:0,他引:3
M. Sawada Daniel Cossette Barry Wellar Tolga Kurt 《Government Information Quarterly》2006,23(3-4):454
Millions of Canadians residing in Canada's northern, isolated, rural, and remote communities do not have broadband Internet access. This situation has led to a national “broadband divide.” That is, the deployment of wireline broadband is very limited in Canada's northern, isolated, rural, and remote areas because of the significant expense of installation and maintenance of the wired infrastructure needed to reach dwellings in these locations.Terrestrial broadband wireless technology, on the other hand, does not entail the same kind of physical infrastructure. As a result, there are dramatic changes in how spatial considerations affect the provision of broadband Internet services (BIS) to areas beyond the urban zone. In particular, the spatial question is now focused on assessing the capacity for different technological solutions to reach profitable population bases, and brings to the forefront organizations that are developing non-line-of-sight (NLOS) technologies that would permit wireless Internet access over much greater distances than current solutions.We begin this paper by establishing the importance of broadband connectivity to Canada's northern, isolated, rural, and remote communities. This discussion comments on the role of the Government of Canada in the provision of broadband connectivity to residents of these communities, and outlines the current regulatory issues that govern wireless services and policy formulation.The second part of the paper illustrates the use of geographic information system (GIS) approaches in the study of wireless broadband planning and deployment. Case study findings suggest that GIS applications can make a significant contribution to the analysis of wireless deployment planning, to the understanding of the relationships between wireless signal sources and consumers, and to the spatial configuration of terrestrial wireless broadband networks. We conclude the paper by discussing how the GIS approach employed could be used to inform the public policy process with regard to increasing access to broadband Internet services in all regions of the country, and thereby providing the opportunity for all Canadians, regardless of location, to fully participate in the Information Society. 相似文献
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This article explores the evolution of the role of academic journal articles submitted to the UK's Research Assessment Exercise (RAE). By reviewing their role, it is possible to see how the changes from quantitative to qualitative assessment (and the resulting problems surrounding the definition of ‘quality’ journals) has impacted both on the journals selected by academics for publishing their research and the assessment of them. Although only one part of RAE submissions, the listing of published research outputs provides the primary evidence for research quality to most RAE panels, and is a significant driver of the final grade awarded, and thus the funding received by submitting institutions. The RAE, being a peer‐reviewed assessment exercise, mirrors in some ways the peer‐review process immured within scholarly publication. The developing role of journal publications as a vehicle for academic research output is examined via the chronology of the RAE, before assessing the current situation in which published journal output formed almost 70% of all output assessed by RAE panels in the latest exercise. The impact of this increased importance of academic journals in the assessment process is considered not only for academics but also for the wider community, i.e. publishers and libraries. 相似文献
35.
Scale and Translation Invariant Collaborative Filtering Systems 总被引:1,自引:0,他引:1
Daniel Lemire 《Information Retrieval》2005,8(1):129-150
Collaborative filtering systems are prediction algorithms over sparse data sets of user preferences. We modify a wide range of state-of-the-art collaborative filtering systems to make them scale and translation invariant and generally improve their accuracy without increasing their computational cost. Using the EachMovie and the Jester data sets, we show that learning-free constant time scale and translation invariant schemes outperforms other learning-free constant time schemes by at least 3% and perform as well as expensive memory-based schemes (within 4%). Over the Jester data set, we show that a scale and translation invariant Eigentaste algorithm outperforms Eigentaste 2.0 by 20%. These results suggest that scale and translation invariance is a desirable property. 相似文献
36.
Black-dyed artefacts are found in museums worldwide, many produced using an iron-tannate compound. Deterioration of iron-tannate dyed artefacts is an international preservation issue: in New Zealand the deterioration of paru (iron-tannate) dyed Māori textiles is widespread. This article reports experimental work testing the efficacy of sodium alginate, a consolidant developed for deteriorated paru-dyed muka (fibre from harakeke; Phormium tenax). The colour stability, strength retention, and acidity of paru-dyed muka consolidated with sodium alginate (0.25, 0.5, and 1% w/v in water) was tested pre- and post-artificial light ageing. This study found that sodium alginate had no negative effect on paru-dyed muka and in some cases provided benefit. Interestingly, the colour of paru-dyed muka is substantially more stable in UV-filtered light than previously recognised. Also microfading results were in agreement with visual assessments of colour change at 1 Mlux hour exposure, providing confidence in this relatively new technique to assess colour change. 相似文献
37.
Increased genetic testing in personalized medicine presents unique challenges for couples, including managing disease risk and potential discrimination as a couple. This study investigated couples’ conflicts and support gaps as they coped with perceived genetic discrimination. We also explored the degree to which communal coping was beneficial in reducing support gaps and ultimately stress. Dyadic analysis of married adults (N?=?266, 133 couples), in which one person had the genetic risk for serious illness, showed that perceived discrimination predicted more frequent conflicts about alpha-1 antitrypsin deficiency-related treatment, privacy boundaries, and finances, which, in turn, predicted wider gaps in emotion and esteem support, and greater stress for both spouses. Communal coping predicted lower support gaps for both partners and marginally lower stress. 相似文献
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39.
Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system. 相似文献
40.
A number of voices have emerged in U.S. political discourse questioning the legitimacy of American exceptionalism, suggesting we are in a “post-American world.” Our research examines the effects that political messages that explicitly challenge American exceptionalism can have on U.S. public opinion. Drawing upon social identity theory, we find that explicit challenges to American exceptionalism significantly impact Americans’ views toward their own nation, their willingness to denigrate foreign publics, and their broader foreign policy preferences. 相似文献