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   1906篇
  免费   118篇
  2024篇
  2023年   13篇
  2022年   10篇
  2021年   37篇
  2020年   55篇
  2019年   57篇
  2018年   71篇
  2017年   96篇
  2016年   91篇
  2015年   72篇
  2014年   75篇
  2013年   254篇
  2012年   139篇
  2011年   107篇
  2010年   62篇
  2009年   71篇
  2008年   82篇
  2007年   78篇
  2006年   58篇
  2005年   41篇
  2004年   42篇
  2003年   39篇
  2002年   32篇
  2001年   23篇
  2000年   18篇
  1999年   18篇
  1998年   13篇
  1997年   9篇
  1996年   10篇
  1994年   12篇
  1993年   13篇
  1992年   18篇
  1991年   14篇
  1990年   13篇
  1989年   11篇
  1988年   9篇
  1987年   10篇
  1986年   13篇
  1984年   14篇
  1983年   13篇
  1982年   10篇
  1981年   11篇
  1980年   13篇
  1979年   20篇
  1978年   18篇
  1974年   9篇
  1972年   9篇
  1971年   9篇
  1969年   8篇
  1968年   9篇
  1967年   9篇
排序方式: 共有2024条查询结果,搜索用时 9 毫秒
991.
992.
993.
Making computer imagery more responsive and realistic is one of the most basic goals of graphics researchers, and adaptive display is one of the primary means for achieving it. While previous displays have achieved a spatial adaptivity, our research focuses on achieving temporal adaptivity--sampling some regions not only more densely, but also more often. We use closed loop feedback to guide sampling to image regions that change significantly over space or time. Adaptive reconstruction emphasizes older samples in static settings, resulting in sharper images; and new samples in dynamic settings, resulting in images that may be blurry but are up-to-date. In terms of peak signal-to-noise ratio, this prototype produces much better image streams than nonadaptive renderers with the same simulated sampling rates. This new display also offers new opportunities for adapting to user state, allowing adaptive response both where and when it is needed. Our prototype system already responds interactively to changes in the user's viewpoint, it might also respond to any of a number of other indications of user state, including eye tracking, repeatedly manipulated objects, and biometrics.  相似文献   
994.
McSweeney and Weatherly (1998) argued that differential habituation to the reinforcer contributes to the behavioral interactions observed during multiple schedules. The present experiment confirmed that introducing dishabituators into one component of a multiple schedule increases response rate in the other, constant, component. During baseline, pigeons and rats responded on multiple variable interval 30-s variable interval 30-s schedules. During experimental conditions, subjects responded on the same schedule except that a dishabituating stimulus (manipulation of a light) was also presented randomly during one of the components. Constant-component responding was faster during the experimental than during the baseline conditions. This difference in responding grew larger across the session. The within-session pattern of responding was similar for the two components of each multiple schedule. Qualitatively similar results were observed for rats and pigeons. These results suggest that behavioral interactions sometimes arise from a change in reinforcer effectiveness between the baseline and experimental phases of the experiment, rather than from an assessment of reinforcer relativity (a comparison of reinforcers delivered during the two components in the experimental phase). Behavioral contrast and induction are sometimes produced by similar factors.  相似文献   
995.
Compatibilism and the Notion of Rendering Something False   总被引:2,自引:0,他引:2  
In my paper I am concerned with Peter van Inwagen's Consequence Argument. I focus on its probably best known version. In this form it crucially employs the notion of rendering a proposition false, anotion that has never been made sufficiently clear. The main aim of my paper is to shed light on thisnotion. The explications offered so far in thedebate all are based on modal concepts. Iargue that for sufficient results a ``stronger',hyper-intensional concept is needed, namely theconcept expressed by the word ``because'. I show that my analysis is superior to the prior ones. On the basis of this analysis I further explain why van Inwagen's argument fails.  相似文献   
996.
Demographic characteristics, family financial strain, neighborhood-level economic disadvantage, and state of residence were tested as predictors of observed warmth, hostility, and self-reported marital quality. Participants were 202 married African American couples who resided in a range of neighborhood contexts. Neighborhood-level economic disadvantage predicted lower warmth during marital interactions, as did residence in the rural south. Consistent with the family stress model (e.g., Conger & Elder, 1994), family financial strain predicted lower perceived marital quality. Unexpectedly, neighborhood-level economic disadvantage predicted higher marital quality. Social comparison processes and degree of exposure to racially based discrimination are considered as explanations for this unexpected result. The importance of context in relationship outcomes is highlighted.  相似文献   
997.
Three experiments investigated the contribution of domain general processes to imagined transformations of whole body perspective. In a task where participants make left–right judgements about a schematic human figure, reaction times made from the point of view of the figure are longer when the figure does not share the same spatial orientation as the participant and are substantially longer than those made from the participant's own point of view. These phenomena have been attributed to a specialised mechanism for imagined perspective transformations. In the present experiments, the effect of orientation on performance was influenced by factors that affect spatial stimulus–response (S–R) compatibility; it was attenuated with reduced dimensional overlap and reversed by crossed S–R mappings. Performance in a control experiment in which no figure was present suggests that processes moderating S–R mappings may account for the effect of adopting another's point of view. Our findings demonstrate a role for domain general processes in imagined transformations of whole body perspective, imply that egocentric codes for spatial relationships within visually presented bodies are automatically generated, and undermine evidence for a specialised mechanism for imagined perspective transformations.  相似文献   
998.
In five experiments, we investigated whether expected retention intervals affect subjects’ encoding strategies. In the first four experiments, our subjects studied paired associates consisting of words from the Graduate Record Exam and a synonym. They were told to expect a test on a word pair after either a short or a longer interval. Subjects were tested on most pairs after the expected retention interval. For some pairs, however, subjects were tested after the other retention interval, allowing for a comparison of performance at a given retention interval conditional upon the expected retention interval. No effect of the expected retention interval was found for 1 min versus 4 min (Exp. 1), 30 s versus 3 min (Exp. 2), and 30 s versus 10 min (Exps. 3 and 4), even when subjects were given complete control over the pacing of study items (Exp. 4). However, when the difference between the expected retention intervals was increased massively (10 min vs. 24 h; Exp. 5), subjects remembered more items that they expected to be tested sooner, an effect consistent with the idea that they traded off efforts to remember items for the later test versus items that were about to be tested. Overall, this set of results accords with much of the test-expectancy literature, revealing that subjects are often reluctant to adjust encoding strategies on an item-by-item basis, and when they do, they usually make quantitative, rather than qualitative, adjustments.  相似文献   
999.
Much is known about how the emotional content of words affects memory for those words, but only recently have researchers begun to investigate whether emotional content influences metamemory—that is, learners’ assessments of what is or is not memorable. The present study replicated recent work demonstrating that judgments of learning (JOLs) do indeed reflect the superior memorability of words with emotional content. We further contrasted two hypotheses regarding this effect: a physiological account in which emotional words are judged to be more memorable because of their arousing properties, versus a cognitive account in which emotional words are judged to be more memorable because of their cognitive distinctiveness. Two results supported the latter account. First, both normed arousal (Exp. 1) and normed valence (Exp. 2) independently influenced JOLs, even though only an effect of arousal would be expected under a physiological account. Second, emotional content no longer influenced JOLs in a design (Exp. 3) that reduced the primary distinctiveness of emotional words by using a single list of words in which normed valence and arousal were varied continuously. These results suggest that the metamnemonic benefit of emotional words likely stems from cognitive factors.  相似文献   
1000.
Despite literature suggesting a relationship between child maltreatment and suicidal ideation, few studies have examined the prospective course of this relationship. The current study examined this relationship in a sample of 682 community youth who were followed over the course of 3 years. Repeated measures of suicidal ideation, emotional maltreatment, and depressive symptom severity were examined in multi-wave path analysis models. Overall, results suggest that emotional maltreatment over time contributes uniquely to the prospective prediction of suicidal ideation, even when controlling for age, previous suicidal ideation, biological sex, and depression symptom severity. Unlike previous studies that have only measured emotional maltreatment at one-time point, the current study demonstrates that emotional maltreatment contributes unique risk to suicidal ideation prospectively among youth. Results speak to the importance of examining emotional maltreatment and suicidal ideation within prospective models of risk and suggest that emotional maltreatment is a robust predictor of suicidal ideation, over and above history of suicidal ideation and depression.  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