排序方式： 共有32条查询结果，搜索用时 31 毫秒
1.
基于细胞神经网络(Cellular Neural Networks)的数字图像加密算法,利用细胞神经网络独有特性,构造一个五维的混沌序列作为秘钥源,在此基础上利用Logistic混沌序列图像像素置乱算法,从而实现对图像加密.编程模拟仿真实验表明,加密图像置乱度高,相邻像素的相关性小,抗攻击性强,安全性更高.最后对明文和密文进行相关性分析,从理论上验证了该加密算法的可靠性. 相似文献
2.
Chengsen Ru Jintao Tang Shasha Li Songxian Xie Ting Wang 《Information processing & management》2018,54(4):593-608
Distant supervision (DS) has the advantage of automatically generating large amounts of labelled training data and has been widely used for relation extraction. However, there are usually many wrong labels in the automatically labelled data in distant supervision (Riedel, Yao, & McCallum, 2010). This paper presents a novel method to reduce the wrong labels. The proposed method uses the semantic Jaccard with word embedding to measure the semantic similarity between the relation phrase in the knowledge base and the dependency phrases between two entities in a sentence to filter the wrong labels. In the process of reducing wrong labels, the semantic Jaccard algorithm selects a core dependency phrase to represent the candidate relation in a sentence, which can capture features for relation classification and avoid the negative impact from irrelevant term sequences that previous neural network models of relation extraction often suffer. In the process of relation classification, the core dependency phrases are also used as the input of a convolutional neural network (CNN) for relation classification. The experimental results show that compared with the methods using original DS data, the methods using filtered DS data performed much better in relation extraction. It indicates that the semantic similarity based method is effective in reducing wrong labels. The relation extraction performance of the CNN model using the core dependency phrases as input is the best of all, which indicates that using the core dependency phrases as input of CNN is enough to capture the features for relation classification and could avoid negative impact from irrelevant terms. 相似文献
3.
《Information processing & management》2023,60(3):103262
Smart wheelchairs based on brain–computer interface (BCI) have been widely utilized recently to address certain mobility problems for people with disability. In this paper, we present SmartRolling, an intuitive human–machine interaction approach for the direct control of robotic wheelchair that jointly leverages EEG signals and motion sensing techniques. Specifically, SmartRolling offers two wheelchair-actuation modes for users with different physical conditions: (1) head motion only — people who are severely disabled but able to do basic tasks using eyes and head, and (2) head and hands motion — in addition to type 1, people who can use functioning hands/arms for extra tasks. The system issues operation commands by recognizing different EEG patterns elicited by motor execution (ME) tasks including eye blink, jaw clench, and fist open/close, while at the same time estimates users’ steering intentions based on their facing direction by leveraging inertial measurements and computer vision techniques. The experiment results demonstrate that the proposed system is robust and effective to meets the individual’s needs and has great potential to promote better health. 相似文献
4.
The present study examines the influence of relative minority size on perceptions of argument quality and attitude change. Strong and weak arguments for both cautious and risky positions were presented in conjunction with information describing the size of minority factions as either small or large. Results demonstrated that cautious argument quality influenced perceptions of argument quality only when the majority advocated a cautious position or when the minority faction was large. Results are discussed in light of their implications for normative and informational influences in group polarization. 相似文献
5.
《Public Library Quarterly》2013,32(2):73-74
Abstract A first-person account of the drama inside the CNN newsroom on the day the Hurricane Katrina rocked the US Gulf Coast. Elliot Masie's document shows how the gathering and reporting of the news has become more eclectic, technical and under the influence of citizen-journalists who shape the news by what they send electronically to news outlets and to each other. In the librarian's job of helping researchers access information about the news has become more complex because the traditional linkage of reporting, editing and publishing has broken down. 相似文献
6.
CNN与Fox News竞争分析 总被引：2，自引：0，他引：2
CNN和FoxNews在世界有线电视中占有重要地位,1996年至今是美国有线电视网飞速发展的黄金时期,CNN与Foxnews之间的两强竞争格局是推动有线网健康快速发展的核心动力,理解CNN与FOXNews之间的竞争关系是十年来美国有线新闻网发展的关键,为探寻美国有线电视未来的方向提供了可能。 相似文献
7.
In the introduction to a police audio recording of Bristol Palin describing her family’s involvement in an Alaska house party brawl, CNN anchor Carol Costello commented: “This is quite possibly the best minute and a half of audio we’ve ever come across.” The incident, however, involved an alleged assault—an act that mainstream journalism generally reports in a serious manner. Costello’s glib treatment of the event could therefore be seen as potentially breaching the boundaries of professional practice, which brought a widespread media response from both mainstream organizations and right-leaning blogs. Through textual analysis of these items, this study illustrates the challenge of conducting media boundary work—and the role strain that results—when the subject of a story occupies space within both entertainment and news spheres. 相似文献
8.
Erga Atad 《Journalism Practice》2017,11(6):760-776
This study examines whether news broadcasts across nations are more cosmopolitan or parochial in their essence. To answer this question, the article proposes two unique theoretical concepts: “global newsworthiness” and “reversed domestication.” Global newsworthiness refers to news broadcasts that include ranges of countries, selected by several different reporting criteria. Reversed domestication refers to the connection made between the country of origin of the broadcasting media and the news content. Four television news networks were compared—CNN International, BBC World News, Al Jazeera English and France 24. The findings point to different levels of global newsworthiness and reversed domestication. 相似文献
9.
Dan Berkowitz 《Journalism Practice》2016,10(1):1-17
Following a twerk-heavy performance by Miley Cyrus on the Video Music Awards program, CNN featured the story on the top of its website. The Onion—a fake-news organization—then ran a satirical column purporting to be by CNN's Web editor explaining this decision. Through textual analysis, this paper demonstrates how a Fifth Estate comprised of bloggers, columnists and fake-news organizations worked to relocate mainstream journalism back to within its professional boundaries. 相似文献
10.
国内众多新闻传媒专家的研究显示,美国主流媒体对中国的报道存在丑化中国的倾向。而针对中国学者对美媒体的批判,美国相关学者也进行了相应的反击。基于新闻界学者的研究现状,本文拟从语言学角度,运用批评话语分析的语篇分析方法,以美国最大的有线电视网络媒体CNN对中国的新闻报道为例,探析美国媒体对中国报道的典型语言手段,以及由此体现的美国媒体对中国报道的主观倾向。 相似文献