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31.
由于机会路由能够利用无线信道的广播特性和有损特性,因此一直是提高无线网络路由性能的一个很有效的途径。提出一种基于深度强化学习的无线多跳网络能量高效机会路由算法,该算法使得智能体能够通过训练学习最优的路由策略,以通过机会路由的方式减少传输时间,同时平衡能耗延长网络寿命。此外,本算法还可以极大地缓解冷启动问题并获得较好的初始性能。仿真结果表明,与现有算法相比,该算法具有更好的性能。 相似文献
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关于图书馆学专门研究方法之分析 总被引:13,自引:1,他引:13
在阐述图书馆学专门研究方法的意义的基础上,介绍关于图书馆学专门研究方法的三神代表性观点。指出在分析图书馆学专门研究方法时要着重明确两种关系,即专门研究方法与哲学方法、一般研究方法的关系,专门研究方法与工作方法之间的关系。 相似文献
34.
口述历史在地方文献工作中的意义及实践 总被引:5,自引:1,他引:5
文章首先简要介绍现代口述历史的含义及其发展历程,阐述了口述历史对于地方文献工作的意义,并结合自己的工作实践探索开展口述历史工作的方法和需要注意的问题。 相似文献
35.
网上参考咨询服务活动与知识库建设 总被引:4,自引:0,他引:4
论述了图书馆网上参考咨询的特点及其网上参考咨询知识库建设的重要性,阐释了网上参考咨询知识库建设和网上参考咨询服务活动之间的关系。结合目前通行的网上知识导航等各种服务模式,与建立网上知识库的实践需求等进行了比较分析。 相似文献
36.
Sandra L De Groote Marceline Doranski 《Journal of the Medical Library Association》2004,92(3):341-348
OBJECTIVES: The purpose of this study is to determine how personal digital assistants (PDAs) are used on an academic health sciences campus to define the level of training and support the library can provide to the students and faculty. METHOD: A Web-based questionnaire was developed. A total of 1,538 health sciences faculty and residents were sent an email message requesting participation. Data from the returned surveys were analyzed with SPSS. RESULTS: Sixty-one percent of survey respondents used PDAs. The address book, date book, and calculator were the most common uses reported for PDAs. Residents also reported a high use of drug databases on their PDAs. Most survey respondents indicated they would like to learn more about clinical resources for PDAs. CONCLUSIONS: Many opportunities exist for librarians to provide training and support for PDAs, in addition to evaluation and promotion of clinical software for PDAs. 相似文献
37.
Sandra L De Groote Mary Shultz Marceline Doranski 《Journal of the Medical Library Association》2005,93(2):223-228
PURPOSE: The purpose was to determine the impact of online journals on the citation patterns of medical faculty. This study looked at whether researchers were more likely to limit the resources they consulted and cited to those journals available online rather than those only in print. SETTING: Faculty publications from the college of medicine at a large urban university were examined for this study. The faculty publications from a regional medical college of the same university were also examined in the study. The number of online journals available for faculty, staff, and students at this institution has increased from an initial core of 15 online journals in 1998 to over 11,000 online journals in 2004. METHODOLOGY: Searches by author affiliation were performed in the Web of Science to find all articles written by faculty members in the college of medicine at the selected institution. Searches were conducted for the following years: 1993, 1996, 1999, and 2002. Cited references from each faculty-authored article were recorded, and the corresponding cited journals were coded into four categories based on their availability at the institution in this study: print only, print and online, online only, and not owned. Results were analyzed using SPSS. RESULTS: The number of journals cited per year continued to increase from 1993 to 2002. The results did not indicate that researchers were more likely to cite online journals or were less likely to cite journals only in print. At the regional location where the number of print-only journals was minimal, use of the print-only journals did decrease in 2002, although not significantly. CONCLUSION/DISCUSSION: It is possible that electronic access to information (i.e., online databases) has had a positive impact on the number of articles faculty will cite. Results of this study suggest, at this point, that faculty are still accessing the print-only collection, at least for research purposes, and are therefore not sacrificing quality for convenience. 相似文献
38.
Gaëlle Ouvrein Sara Pabian Juan Manuel Machimbarrena Charlotte J.S. De Backer Heidi Vandebosch 《Communication Research Reports》2018,35(3):261-271
Journalists and readers of celebrity news regularly bash celebrities online, a behavior that is easily accepted among adolescents. This study investigates whether these attitudes of acceptance differ according to the perpetrator of the bashing (media versus public) and the likeability of the involved celebrity (liked versus disliked). Using a vignette study, we examine adolescent girls’ attitudes toward media (journalists’) and public (readers’) bashing of a generally disliked celebrity (Miley Cyrus) and a generally liked celebrity (Selena Gomez). All participants read an identical negative news story (media bashing) and two related negative reader comments (public bashing). Participants were randomly assigned to read this information about either Miley Cyrus or Selena Gomez. Results of a mixed-design ANOVA showed that the girls had less negative attitudes toward media bashing compared with public bashing. Moreover, they more easily accepted the bashing of a disliked celebrity than the bashing of a liked celebrity. 相似文献
39.
Laura Jacobs Alyt Damstra Mark Boukes Knut De Swert 《Mass Communication and Society》2018,21(4):473-497
Although prior studies investigating immigration news typically documented a dominant focus on negativity and threats, only limited empirical research is available, which scrutinizes the way real-world developments affect these patterns in immigration news. This study aims to fill this void. First, we report results of a large-scale and longitudinal content analysis (N = 4,340,757) of trends in immigration news coverage in two Western European cases, Flanders (the northern, Dutch-speaking, largest region of Belgium) and the Netherlands, from 1999 to 2015. Both the salience of immigration as a news topic on itself and its linkages with three prominent issues (i.e., crime, terrorism, and socioeconomic issues) are explored. Second, this study builds on previous insights by comparing dynamics in immigration news to real-world events and developments. Overall, the results show that the linkage of immigration to issues of crime, terrorism, and the economy in Flemish and Dutch newspapers was considerable throughout the 17-year period under study. Yet there is limited evidence for a close relationship between news and real-life developments; hence, trends in immigration news seem largely unaffected by trends in society. 相似文献
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