全文获取类型
收费全文 | 24223篇 |
免费 | 337篇 |
国内免费 | 30篇 |
专业分类
教育 | 17224篇 |
科学研究 | 1985篇 |
各国文化 | 255篇 |
体育 | 2407篇 |
综合类 | 12篇 |
文化理论 | 213篇 |
信息传播 | 2494篇 |
出版年
2021年 | 241篇 |
2020年 | 371篇 |
2019年 | 557篇 |
2018年 | 751篇 |
2017年 | 691篇 |
2016年 | 680篇 |
2015年 | 425篇 |
2014年 | 570篇 |
2013年 | 4401篇 |
2012年 | 518篇 |
2011年 | 568篇 |
2010年 | 434篇 |
2009年 | 463篇 |
2008年 | 513篇 |
2007年 | 470篇 |
2006年 | 456篇 |
2005年 | 394篇 |
2004年 | 411篇 |
2003年 | 317篇 |
2002年 | 344篇 |
2001年 | 469篇 |
2000年 | 514篇 |
1999年 | 445篇 |
1998年 | 260篇 |
1997年 | 254篇 |
1996年 | 311篇 |
1995年 | 248篇 |
1994年 | 262篇 |
1993年 | 225篇 |
1992年 | 356篇 |
1991年 | 371篇 |
1990年 | 348篇 |
1989年 | 369篇 |
1988年 | 338篇 |
1987年 | 326篇 |
1986年 | 325篇 |
1985年 | 371篇 |
1984年 | 294篇 |
1983年 | 306篇 |
1982年 | 241篇 |
1981年 | 247篇 |
1980年 | 261篇 |
1979年 | 351篇 |
1978年 | 259篇 |
1977年 | 240篇 |
1976年 | 202篇 |
1975年 | 182篇 |
1974年 | 183篇 |
1973年 | 180篇 |
1971年 | 175篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
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
132.
Debasis?GangulyEmail authorView authors OrcID profile Gareth?J.?F.?Jones Aarón?Ramírez-de-la-Cruz Gabriela?Ramírez-de-la-Rosa Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents. 相似文献
133.
Franklin J. Boster Rain Wuyu Liu Ying Cheng Wonkyung Kim Sonia Jawaid Shaikh 《Communication Studies》2018,69(1):4-22
Stickiness refers to the set of persuasive message properties: simple, unexpected, concrete, credible, emotional, and stories (SUCCES). Heath and Heath (2007) argue that a sticky message is expected to be more memorable and hence more persuasive than a non-sticky message. A 2 (sticky v. non-sticky message) x 3 (pretest v. posttest v. delayed test) longitudinal experiment is employed to examine the persuasiveness of sticky messages on applying sunscreen. Results of a mixed model analysis of variance show that the sticky message produces attitudes and behaviors more favorable to the message recommendation than the non-sticky message. Specifically, a time × message induction non-additive effect was found, which sustained only in the sticky message condition across time. Despite this interesting effect, its explanation remains elusive. 相似文献
134.
Inconsistency is often considered an indication of deceit. The conceptualization of consistency used in deception research, however, has not made a clear distinction between two concepts long differentiated by philosophers: coherence and correspondence. The existing literature suggests that coherence is not generally useful for deception detection. Correspondence, however, appears to be quite useful. The present research developed a model of how correspondence is utilized to make judgments, and this article reports on four studies designed to elaborate on the model. The results suggest that judges attend strongly to correspondence and that they do so in an additive fashion. As noncorrespondent information accumulates, an increasingly smaller proportion of judges make truthful assessments of guilty suspects. This work provides a basic framework for examining how information is utilized to make deception judgments and forms the correspondence and coherence module of truth-default theory. 相似文献
135.
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
136.
This study replicated a previous research project addressing connections between family-of-origin communication and organizational dissent expression. We predicted that family communication patterns (FCPs), specifically conversation and conformity orientations, would predict upward, lateral, and displaced dissent. As in the original study, significant findings emerged for upward dissent and conformity orientation. This replication study indicated family type as an inconsistent predictor of expressed dissent. Contrary to the original study, we found no evidence to support a connection between pluralistic family types and upward dissent. Finally, as an extension of the original study we analyzed effects of FCPs on displaced dissent, finding an inverse association with conversation orientation. Implications for future research are discussed. 相似文献
137.
138.
Raymond J. Pingree Elizabeth Stoycheff Mingxiao Sui Jason T. Peifer 《Mass Communication and Society》2018,21(5):555-584
The mere perception that news has given certain problems more coverage can lead the audience to assume that those problems are more important. Given that the news media, at times, obsesses over relatively trivial matters, and given that the audience is increasingly able to filter media exposure, it is worth asking what happens when audience members perceive that recent media coverage has not emphasized any very important problems. In such cases, audience members might assume that any problems facing the nation must not be particularly important. We explicate this attitude of political complacency, test whether perceived media agendas lacking important problems can influence it, and explore whether complacency helps explain political disengagement. We also explore whether these effects generalize beyond news, to new media gatekeepers such as Twitter. Two experiments tested effects of a perceived absence of important problems in recent news or Twitter content. In the case of news, but not Twitter, this increased complacency in both studies. Study 2 added a no-exposure control and found that effects on complacency were driven by the cueing of nonproblem stories, not by the absence of problem story cues. Both studies validated complacency as a predictor of political disengagement. 相似文献
139.
Word embeddings and convolutional neural networks (CNN) have attracted extensive attention in various classification tasks for Twitter, e.g. sentiment classification. However, the effect of the configuration used to generate the word embeddings on the classification performance has not been studied in the existing literature. In this paper, using a Twitter election classification task that aims to detect election-related tweets, we investigate the impact of the background dataset used to train the embedding models, as well as the parameters of the word embedding training process, namely the context window size, the dimensionality and the number of negative samples, on the attained classification performance. By comparing the classification results of word embedding models that have been trained using different background corpora (e.g. Wikipedia articles and Twitter microposts), we show that the background data should align with the Twitter classification dataset both in data type and time period to achieve significantly better performance compared to baselines such as SVM with TF-IDF. Moreover, by evaluating the results of word embedding models trained using various context window sizes and dimensionalities, we find that large context window and dimension sizes are preferable to improve the performance. However, the number of negative samples parameter does not significantly affect the performance of the CNN classifiers. Our experimental results also show that choosing the correct word embedding model for use with CNN leads to statistically significant improvements over various baselines such as random, SVM with TF-IDF and SVM with word embeddings. Finally, for out-of-vocabulary (OOV) words that are not available in the learned word embedding models, we show that a simple OOV strategy to randomly initialise the OOV words without any prior knowledge is sufficient to attain a good classification performance among the current OOV strategies (e.g. a random initialisation using statistics of the pre-trained word embedding models). 相似文献
140.