首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   555篇
  免费   10篇
教育   388篇
科学研究   22篇
各国文化   5篇
体育   81篇
文化理论   6篇
信息传播   63篇
  2022年   5篇
  2021年   4篇
  2020年   16篇
  2019年   27篇
  2018年   32篇
  2017年   30篇
  2016年   20篇
  2015年   13篇
  2014年   22篇
  2013年   131篇
  2012年   19篇
  2011年   14篇
  2010年   11篇
  2009年   9篇
  2008年   5篇
  2007年   15篇
  2006年   19篇
  2005年   9篇
  2004年   9篇
  2003年   5篇
  2002年   5篇
  2001年   8篇
  2000年   12篇
  1999年   10篇
  1998年   9篇
  1997年   8篇
  1996年   2篇
  1995年   5篇
  1994年   3篇
  1993年   5篇
  1992年   3篇
  1991年   4篇
  1989年   5篇
  1987年   5篇
  1986年   5篇
  1985年   3篇
  1984年   3篇
  1983年   4篇
  1982年   5篇
  1981年   7篇
  1980年   5篇
  1979年   5篇
  1978年   5篇
  1977年   2篇
  1975年   4篇
  1974年   2篇
  1973年   3篇
  1972年   3篇
  1970年   2篇
  1912年   3篇
排序方式: 共有565条查询结果,搜索用时 265 毫秒
1.
2.
3.
4.
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   
5.
ABSTRACT

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.  相似文献   
6.
The construction of a history curriculum for England and for Wales under the terms of the 1988 Education Reform Act occasioned more debate in the media than any other subject in the National Curriculum. The links between the content of a history syllabus and perceptions within both nations of the part this plays in moulding national spirit made this inevitable. The disparity of view between the two groups charged with devising the syllabus and the government, particularly the Prime Minister, heightened the tension. This article explores the way in which consequent political, professional and public discussion was covered in the whole range of national newspapers. It is argued that the failure of the London press to comprehend the situation in Wales reduced significantly its appreciation of the processes involved in the making of the history curriculum.  相似文献   
7.
8.
This paper reports on efforts aimed toward the development of more effective procedures for identifying mothers who are at elevated risk for problems in parenting. We present data from two independent samples of known maladaptors and corresponding comparison mothers and report on our attempts to cross-validate a promising screening instrument composed of items that index social support and parenting attitudes. The resultant 20-item scale correctly identified over 90% of maladaptive and comparison mothers. When this scale was cross-validated on a second independent sample of maladaptors and comparison mothers, it was again almost 90% accurate. Issues concerning the field application of this promising instrument are discussed and its possible limitations are considered.  相似文献   
9.
Selective universities regularly employ policies that favor children of alumni (known as legacies) in undergraduate admissions. Since alumni from selective colleges and universities historically have been disproportionately white, admissions policies that favor legacies have disproportionately benefited white students. For this reason, legacy policies lead to additional costs in terms of reductions in racial diversity. As larger numbers of minority students graduate from colleges and universities and have children, however, the potential pool of legacy applicants will change markedly in racial composition. This analysis begins with a review of the history and objectives of the preference for children of alumni in undergraduate admissions. We then consider the specific case of the University of Virginia and employ demographic techniques to predict the racial composition of the pool of potential legacy applicants to the university. Significant changes in the racial composition of classes that graduated from the University of Virginia from the late 1960s through the 1970s foreshadow similar changes in the characteristics of alumni children maturing through the next two decades.  相似文献   
10.
Lifelong Debt: Rates of Return to Mature Study   总被引:2,自引:0,他引:2  
High rates of return to first degrees have been used to justify increased student financial contributions to higher education. However, no discrete study of rates of return to mature graduates has been carried out although mature graduates now form a significant proportion of the student population. The General Household Survey 1983–1992 was used to examine the earnings of mature graduates compared with those of matriculates. The GHS yielded 616 mature graduate men in full-time work and 296 mature graduate women who were in full-time employment. It was found that the rate of return to mature male graduates was just above one per cent. With recent added costs, new male mature graduates can be forecast to make a sizeable loss on their study. Rates of return to women mature graduates were higher, between five and six per cent, and, based on these figures, the recent increased cost of mature graduate study should be covered by increased earnings. However, these calculations are based on average earnings for the modal age cohort of mature graduates. Those who are older when they complete or earn below the average (a large percentage) will not recoup the costs of study.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号