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   967篇
  免费   5篇
  国内免费   8篇
  2024年   7篇
  2023年   33篇
  2022年   20篇
  2021年   39篇
  2020年   77篇
  2019年   67篇
  2018年   43篇
  2017年   79篇
  2016年   80篇
  2015年   67篇
  2014年   56篇
  2013年   365篇
  2012年   3篇
  2011年   5篇
  2010年   3篇
  2009年   6篇
  2008年   4篇
  2007年   2篇
  2006年   2篇
  2005年   4篇
  2003年   2篇
  2002年   2篇
  1997年   1篇
  1994年   1篇
  1991年   1篇
  1983年   2篇
  1982年   2篇
  1980年   2篇
  1979年   1篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
排序方式: 共有980条查询结果,搜索用时 15 毫秒
171.
172.
173.
This study tested the Bayesian journey-to-crime (JTC) model by gender and age for serial offenders from Manchester, England. The data were 4056 crimes committed by 171 serial offenders between 2003 and 2006. The data were subdivided by gender and age group to examine whether accuracy and precision varied by these subgroups. In general, the centre of minimum distance was found to be the most accurate measure, but the Bayesian risk and product measures were found to be the most precise measurements. The traditional ‘distance decay’ type of JTC function did not produce estimates that are as accurate nor as precise as the Bayesian approach. Tests were conducted on whether specific gender and age group JTC functions and origin–destination matrices improved predictability. With the exception of juvenile male offenders, the general functions were more accurate and precise. In terms of building an accurate and precise geographical profiling methodology, the results point to the need to include information on the likely predisposition of neighbourhoods to produce offenders as well as information on the crime opportunities available to offenders. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
174.
在慢性胃炎研究上决策树归纳法之使用已渐增加,以决策树归纳法同时表示信息增益以区别胃炎症状对证型分类之贡献,能更正确地区别慢性胃炎。而信息增益已广泛地用于评估两分分类,仅有很少报导有关多类别慢性胃炎分类,它需要探索多类别慢性胃炎分类之信息增益。本研究提出基于名目及次序样本类结果的决策树归纳法所做的多类别慢性胃炎分类,例如,不同慢性胃炎次型的症状样本,评估是以决策树归纳法与Friedman-Goldszmid,HGC,Cheng判别法之正确率作比较。显示平均正确率64.9%优于前三者且提高1.55%。  相似文献   
175.
176.
One-hundred-and-twenty-eight patients with unilateral hemispheric damage (53 aphasics, 26 nonaphasic left, and 49 right brain-damaged patients) and 25 normal controls were given a test of symbolic gesture comprehension and other tests of verbal comprehension and of reproduction of symbolic gestures. On the test of symbolic gesture interpretation aphasic patients performed significantly worse than any other group of brain-damaged patients. Within the aphasic patients the inability to understand the meaning of symbolic gestures was highly related to the number of semantic errors obtained at a verbal comprehension test. On the contrary, only a mild relationship was found between comprehension and reproduction of symbolic gestures. Some implications of these findings are discussed.  相似文献   
177.
178.
179.
Redundancy gain is an improvement in speeded target detection when the number of targets associated with a single response is increased within a single display. The effect has been clearly demonstrated with specific targets, but it is not clear if it occurs in categorization tasks with non-identical targets. The current study tested the effect of target redundancy on speed and accuracy in a go/no-go categorization task. Targets were digits tilted 45° to the left, and were displayed in unilateral, bilateral, or central displays for either 1500?ms or 100?ms. Redundancy gain only occurred for brief targets displayed bilaterally in the upper visual field. The results indicate that redundancy gain is possible for categorization tasks with some bilateral configurations, supporting a role for interhemispheric processing in redundancy gain. Additionally, the results may indicate that processing strategies mask redundancy gain when participants can view targets for a long period of time.  相似文献   
180.
Work environments characterized by inadequate work conditions have been widely recognized as being particularly prone to the occurrence and exacerbation of bullying behavior. Accordingly, this longitudinal study aimed to explore whether the impact of effort–reward imbalance (ERI) on workplace bullying was mediated by a lower perception of organizational justice, and whether the association between ERI and perceptions of justice was moderated by organizational identification. In the current study, a sample of N = 195 Spanish employees from different occupational sectors filled in an online questionnaire at two different times with a time lag of 8 months. In line with the hypothesized moderated mediation model, results showed that organizational justice mediated the impact of ERI on workplace bullying. Moreover, the effect of perceived ERI on organizational justice was stronger for employees with low organizational identification. Overall, this study can contribute to better understanding how and when ERI boosts the risk of workplace bullying. Accordingly, early intervention designed to buffer the negative effects of ERI should focus on increasing individual levels of organizational identification.  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