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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 study examined two levels of media agenda effects on aggregatepublic opinion from different news sources. The effects wereinvestigated immediately and cumulatively. Content analysisdata from the 2000 U.S. presidential election coverage by fournational news organizations were related to the Gallup pre-electionpoll standings of each candidate. Regression analyses foundthat both the salience of a candidate and the salience of theattributes of a candidate cumulatively, but not immediately,influenced his standing in the polls. An analysis of news sourcessupported the finding that the two levels of agenda-settingeffects seemed mostly cumulative rather than immediate. Newsfrom different sources, however, tended to have effects of differentdegrees and sometimes different directions on candidate pollstandings. Cumulative effects of candidate salience on aggregateopinion change were found for non-partisan and neutral newssourcesreporters, poll reporting and public documentswhereasthe effects of candidate attribute salience mostly came frompartisan sourcesthe candidate himself and members ofthe competing political party. Possible political implicationsof these findings are discussed. 相似文献
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Steve H. Ching 《The Journal of Academic Librarianship》2018,44(2):196-206
The digital shift has provided easy access to academic library users, and yet, the usage of archival collections continues to be low. At the same time, the need for innovation in library services for cultural heritage scholarship and its advancement is emerging. This paper outlines a library-led service-learning program that connects students with lighthouse artifacts, archival collections, scholars in global academia, and wider communities. Student engagement cases are provided to illustrate the way in which the librarian utilizes the Framework of Information Literacy for Higher Education by ACRL to work closely with students. These cases also demonstrate how students can contribute to knowledge creation and preservation efforts for a specific cultural heritage topic that is not static, but which keeps receiving new contributions or additions to the depository. Thus, this paper is an answer to the ACRL's call for pilot projects to be assessed and shared with the wider community of academic librarians and support staff. It also builds on emerging roles for academic libraries like engaged learning. Librarians must move beyond simply seeing themselves as partners. Instead, librarians should see themselves as prime facilitators that co-create and co-develop cultural heritage research and historical projects by connecting actors and resources more effectively than any single actor can do alone. 相似文献
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Daniel Maier A. Waldherr P. Miltner G. Wiedemann A. Niekler A. Keinert 《Communication methods and measures》2018,12(2-3):93-118
ABSTRACTLatent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project. 相似文献
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