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   456篇
  免费   19篇
  国内免费   1篇
  2023年   7篇
  2022年   5篇
  2021年   6篇
  2020年   15篇
  2019年   17篇
  2018年   14篇
  2017年   28篇
  2016年   25篇
  2015年   17篇
  2014年   22篇
  2013年   47篇
  2012年   36篇
  2011年   35篇
  2010年   17篇
  2009年   11篇
  2008年   18篇
  2007年   25篇
  2006年   8篇
  2005年   8篇
  2004年   15篇
  2003年   12篇
  2002年   6篇
  2001年   5篇
  2000年   6篇
  1999年   5篇
  1998年   3篇
  1997年   2篇
  1996年   4篇
  1993年   2篇
  1992年   3篇
  1991年   3篇
  1990年   2篇
  1989年   2篇
  1988年   4篇
  1987年   3篇
  1986年   2篇
  1985年   1篇
  1984年   4篇
  1983年   3篇
  1979年   1篇
  1978年   1篇
  1975年   3篇
  1974年   3篇
  1973年   3篇
  1972年   3篇
  1971年   3篇
  1970年   4篇
  1969年   1篇
  1968年   1篇
  1967年   2篇
排序方式: 共有476条查询结果,搜索用时 15 毫秒
71.
The investigation of the neural underpinnings of increased arithmetic complexity in children is essential for developing educational and therapeutic approaches and might provide novel measures to assess the effects of interventions. Although a few studies in adults and children have revealed the activation of bilateral brain regions during more complex calculations, little is known about children. We investigated 24 children undergoing one-digit and two-digit multiplication tasks while simultaneously recording functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) data. FNIRS data indicated that one-digit multiplication was associated with brain activity in the left superior parietal lobule (SPL) and intraparietal sulcus (IPS) extending to the left motor area, and two-digit multiplication was associated with activity in bilateral SPL, IPS, middle frontal gyrus (MFG), left inferior parietal lobule (IPL), and motor areas. Oscillatory EEG data indicated theta increase and alpha decrease in parieto-occipital sites for both one-digit and two-digit multiplication. The contrast of two-digit versus one-digit multiplication yielded greater activity in right MFG and greater theta increase in frontocentral sites. Activation in frontal areas and theta band data jointly indicate additional domain-general cognitive control and working memory demands for heightened arithmetic complexity in children. The similarity in parietal activation between conditions suggests that children rely on domain-specific magnitude processing not only for two-digit but—in contrast to adults—also for one-digit multiplication problem solving. We conclude that in children, increased arithmetic complexity tested in an ecologically valid setting is associated with domain-general processes but not with alteration of domain-specific magnitude processing.  相似文献   
72.
The objective measurement of physical activity using accelerometers is becoming increasingly popular. There is little consensus, however, about how to analyze acceleration data. One promising approach is the use of reference measurements in which the subjects conduct specific activities. This makes it possible to identify data patterns that indicate these activities for each subject. The drawback of this approach is its rather high cost, in terms of both time and money. We propose a new approach in which a group of children conduct the reference measurements at the same time. We trained support vector machine models on the accelerometer data of 70 children (ages 8–11 years) to predict their activities during those reference measurements. We correctly classified activities with an accuracy of 96.9 % when fitting the individual models for each subject, and 87.5 % when fitting general models for all subjects. The obtained accuracies were comparable to results reported in previous reference measurement studies, in which each subject was measured individually. They were higher than the accuracies obtained by the traditional approach, which transfers accelerometer data to counts and classifies those on the basis of predefined cut points. We concluded that our approach can yield a valuable contribution, particularly to studies with larger samples.  相似文献   
73.
The present work investigated the impact of affect in landmark-based wayfinding. We assumed that affect-laden landmarks improve wayfinding performance and have an impact on later landmark recognition. To investigate our hypotheses, we ran two experiments in a virtual maze. In Experiment 1, we investigated how affect-laden landmarks influence wayfinding and recognition in comparison with neutral landmarks. The aim of Experiment 2 was to focus on the affective valence of a landmark. The memory tasks of both experiments were repeated after 1 week in order to assess memory consolidation. Results showed that the best wayfinding and recognition performance occurs when negatively laden landmarks were used. In comparison with neutral and positively laden landmarks, recognition performance hardly decreased over time for the negatively laden landmarks. Our results not only support findings in the field of emotion research but also expand the concept of semantic landmark salience with respect to emotional responses.  相似文献   
74.
Socially desirable responding may cause differences between preelection polls and election outcomes. Bias-free preelection polls are, however, important because they influence election outcomes. Benefiting from a unique opportunity, we experimentally controlled social desirability using the Crosswise Model in a poll prior to the German federal election in 2013. We found that due to strategic voting, outcome expectations were related to voting intentions; the election outcome was therefore likely distorted by social desirability bias in preelection polls. We recommend using indirect questioning techniques whenever a vote for at least one of the competing parties may be perceived as socially undesirable.  相似文献   
75.
Building on theorizing about contingency inferences, the present research deals with the impact of product category prevalence on consumer choice. We argue that a category's prevalence in the choice set can signal high quality, but the validity depends on the aggregate quality of the choice set. With ever more low‐quality products in the set, high prevalence should increasingly signal poor rather than high quality. When choosing from a poor‐quality set, choices should thus favor products from the rare category. In four experiments, we show that poor‐quality sets increase the proportion of consumers choosing products from a rare category. Furthermore, we show that these effects increase when base rates of a category and quality become more extreme. Finally, Experiment 4 shows that contingency inferences partly mediate the effect of set quality on choice. The results extend previous research on contingency inferences, indicating the adaptive use of base‐rate information in consumer decision making. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
76.
Hoffmann  Melissa L.  Powlishta  Kimberly K.  White  Karen J. 《Sex roles》2004,50(11-12):795-810
Numerous studies have documented gender differences in psychopathology; girls generally report more internalizing symptoms and boys generally report more externalizing symptoms. These gender differences are partially accounted for by the gender-typed personality characteristics of boys and girls. This study was designed to investigate how gender roles influence symptoms of psychopathology by examining the mediating effects of self- and peer-rated competencies. Using a multiple regression approach to path analysis with a sample of primarily White, middle-class high school students, gender roles significantly predicted symptoms of psychopathology and mediated the gender differences in those symptoms. In addition, the adolescents' self- and peer-rated competence in various domains helped to explain the effect of gender roles on symptoms of psychopathology. Specifically, self-rated social attractiveness and global self-worth fully mediated the relation between instrumentality (i.e., masculinity) and internalizing symptoms. Global self-worth and both self- and peer-rated achievement/conduct partially mediated the relation between expressivity (i.e., femininity) and externalizing symptoms. Practical and theoretical implications are discussed.  相似文献   
77.
A changing criterion design was used to examine the effects of two stimuli (a green card and a red card), conditioned via discrimination training, on reducing motor and vocal stereotypy in a youngster with autism while he looked at books. During discrimination training, motor and vocal stereotypy was not interrupted in the presence of a green stimulus, but was interrupted in the presence of a red stimulus using manual guidance and appropriate behavior was reinforced. After the participant demonstrated successful discrimination of the stimuli (i.e., the absence of stereotypy in the presence of a red stimulus and the engagement in stereotypy in the presence of a green stimulus), intervention began. During intervention, upon meeting criterion for latency to engage in motor and vocal stereotypy in the presence of the red stimulus for a target duration, the participant was provided access to the green stimulus, which signaled that motor and vocal stereotypy would not be interrupted. The criterion latency to engage in stereotypy in the presence of the red stimulus was systematically increased. Simultaneously, the duration of access to the green stimulus was systematically decreased. The red and green stimuli were faded from poster boards to colored 10 × 10 cm cards, and stimulus control was generalized to the participant's classroom and to a community setting (i.e., public library). Results are discussed in terms of discrimination training as a useful intervention for reducing motor and vocal stereotypy. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
78.
An experiment is reported studying the impact of objective contingency and contingency judgments on cross-modal evaluative conditioning (EC). Both contingency judgments and evaluative responses were measured after a contingency learning task in which previously neutral sounds served as either weak or strong predictors of affective pictures. Experimental manipulations of contingency and US density were shown to affect contingency judgments. Stronger contingencies were perceived with high contingency and with low US density. The contingency learning task also produced a reliable EC effect. The magnitude of this effect was influenced by an interaction of statistical contingency and US density. Furthermore, the magnitude of EC was correlated with the subjective contingency judgments. Taken together, the results imply that propositional knowledge about the CS-US relationship, as reflected in contingency judgments, moderates evaluative learning. The data are discussed with respect to different accounts of EC.  相似文献   
79.
Episodic memory was assessed using Virtual Reality (VR). Forty-four (44) subjects visualized a target virtual apartment containing specific objects in each room. Then they visualized a second virtual apartment comprised of specific objects and objects shared by the two apartments. Subjects navigated in the virtual apartments in one of the following two conditions: active and passive. Four main episodic memory components were scored from the VR exposures: (1) learning effect; (2) active forgetting effect; (3) strategies at encoding and at retrieval; and (4) false recognitions (FRs). The effect of navigation mode (active vs. passive) on each memory component was examined. Active subjects had better learning and retrieval (recognition hits) performances compared to passive subjects. A beneficial effect of active navigation was also observed on the source-based FR rates. Active subjects made fewer source-based FRs compared to passive subjects. These overall results for the effect of active navigation are discussed in terms of the distinction between item-specific and relational processing.  相似文献   
80.
Three experiments investigated temporal generalization performance under conditions in which participants were instructed to make their decisions as quickly as possible (speed), or were allowed to take their time (accuracy). A previous study (Klapproth & Müller, 2008) had shown that under speeded conditions people were more likely to confuse durations shorter than the standard with the standard than in the accuracy conditions, and a possible explanation of this result is that longer stimulus durations are "truncated" (i.e., people make a judgement about them before they have terminated, thereby shortening their effective duration) and that these truncated durations affect the standard used for the task. Experiment 1 investigated performance under speed and accuracy conditions when comparison durations were close to the standard or further away. No performance difference was found as a function of stimulus spacing, even though responses occurred on average before the longest durations had terminated, but this lack of effect was attributed to "task difficulty" effects changing decision thresholds. In Experiment 2, the standard duration was either the longest or the shortest duration in the comparison set, and differences between speed and accuracy groups occurred only when the comparisons were longer than the standard, supporting the "truncation" hypothesis. A third experiment showed that differences between speed and accuracy groups only occurred if some memory of the standard that was valid for more than one trial was used. In general, the results suggest that the generalization gradient shifts in speeded conditions occur because of truncation of longer comparison durations, which influences the effective standard used for the task.  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