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51.
采用“中国学校课程教学调查项目”中1811名八年级学生及其家长作为样本进行调查,探讨家庭社会经济地位与数学成绩的关系,考察亲子沟通和学业自我效能感的作用机制。结果显示:(1)家庭社会经济地位显著正向影响数学成绩;(2)亲子沟通、学业自我效能感在家庭社会经济地位与数学成绩之间起部分中介作用;(3)亲子沟通、学业自我效能感在家庭社会经济地位与数学成绩之间具有链式中介作用。  相似文献   
52.
Research demonstrating that infants discriminate between small (e.g., 1 vs. 3 dots) and large numerosities (e.g., 8 vs. 16 dots) is central to theories concerning the origins of human numerical abilities. To date, there has been no quantitative meta‐analysis of the infant numerical competency data. Here, we quantitatively synthesize the evidential value of the available literature on infant numerosity discrimination using a meta‐analytic tool called p‐curve. In p‐curve the distribution of available p‐values is analyzed to determine whether the published literature examining particular hypotheses contains evidential value. p‐curves demonstrated evidential value for the hypotheses that infants can discriminate between both small and large unimodal and cross‐modal numerosities. However, the analyses also revealed that the published data on infants’ ability to discriminate between large numerosities is less robust and statistically powered than the data on their ability to discriminate small numerosities. We argue there is a need for adequately powered replication studies to enable stronger inferences in order to use infant data to ground theories concerning the ontogenesis of numerical cognition.  相似文献   
53.
IntroductionLevel 2 driving automation features, such as adaptive cruise control (ACC) combined with lane centering, primarily communicate their operating statuses through the instrument cluster. It remains unclear how interface-specific training and display content influence the ability to understand Level 2 activity in production vehicles.MethodsEighty participants viewed videos recorded from the driver’s point of view in a variety of driving scenarios with Level 2 activity displayed in the instrument cluster of a 2017 Mercedes-Benz E-Class. Half viewed one of two instrument cluster layouts (simple or complex), and half received an orientation to the interface before the experiment. After each video, they were asked about the scenario they had just seen. We then examined what information in the displays participants used to identify Level 2 activity and the usability of the displays.ResultsTraining improved recognition accuracy of when lane centering was temporarily inactive and understanding of why it was inactive. Neither training nor display content affected the ability to recognize when ACC had adjusted the vehicle’s speed or detected a vehicle ahead, or when ACC initially did not detect a lead vehicle and understanding of why it had not detected it. Both factors influenced which sources of information participants used to determine Level 2 activity. Recognition accuracy of system activity improved when participants used valid sources of information. Training, but not display content, improved lane centering usability, but not ACC usability.DiscussionBasic training improves detection of notifications that potentially require further driver action, but not of those that display persistent status information. Training does not result in full understanding of all system notifications or functional limitations, which reinforces the need for intuitive, salient communication about system behavior and its limitations.  相似文献   
54.
Driver distraction is a major cause of road crashes and has a great influence on road safety. In vehicles, one of the common distracting sources is navigation systems (NSs). The navigation system (NS) can distract the driver due to following directions and reading the provided information through its display. These tasks take the driver’s attention from the primary task of driving and may cause poor driving performance, increasing the risk of crashes. In this paper, the effect of the environment (i.e., urban areas and rural areas), the navigation system display (NSD) size, environmental illumination, and gender on young drivers between the ages of 18 and 29 years mental workload was investigated using a simulated driving experiment. To evaluate each driving condition, the NASA-TLX (NASA Task Load Index) workload assessment tool, and a distraction evaluation element, were introduced and used to assess the overall workload, the workload subscales and the distraction by the NSD. The assessment showed a higher perceived overall workload for urban areas and night driving as compared to a rural areas and daytime driving. Moreover, the results showed a greater perceived distraction by the NSD in urban areas compared to driving in rural areas. The subjects also felt distracted when using the small NS compared to using the large NS. The study concluded that urban areas driving, and night driving creates higher perceived workload than rural areas and daytime driving. Furthermore, small NSD leads to more perceived distraction than large NSD while driving. The NSD designers may utilize this research findings to optimize NSD designs to improve driving safety, performance and comfort. Moreover, this study contributes to our understanding of the effect of the NSD size on driving workload and distraction.  相似文献   
55.
A great deal of effort has been made to introduce trust models to assess trustworthiness within virtual societies. The great majority of them makes extensive use of direct experience as the main source of information, considering recommendation/reputation and inferential processes just later, as a secondary mechanism to refine trust assessment. In this kind of networks, unfortunately, direct experience might not always represent the best solution to assess trustworthiness. In fact, their highly dynamic structure promotes an increase of the average number of interconnections among agents. This in turn negatively affects the degree of knowledge the agents possess about each specific individual, i.e. direct experience. To date, however, it has not been said much about how to face these situations.It is fundamental to find an effective approach for trust assessment even in lack of direct experience, which is the central focus of this research. By the means of a multi-agent social simulation, we consider the situation in which an agent can just access indirect knowledge for trust assessment, namely recommendations of specific individuals or whole categories of individuals. Then, we compare the efficiency of these two approaches in order to identify when it is more convenient to rely on the first or on the second one. As expected, our results confirm that the dynamic nature of these networks strongly affects the role of categories. We modeled this feature introducing the “turnover” in the simulations, whereby the higher is the turnover the more convenient it is relying on categories. Besides this confirmatory result, our simulations highlight the higher degree of robustness of categories in the presence of unreliable recommenders. Such a result is even more significant if there is no available information about how reliable the recommenders are.The results we obtained are in accordance with the current literature and can be of important interest for the development of this sector.  相似文献   
56.
The objective of this study is to examine the influence of explicit (team reflexivity) and implicit (transactive memory) coordination processes on the perceived interventional effectiveness of specialized elite units (RAID) of the French national police. We test the hypothesis that transactive memory is a mediating process in the relationship between team reflexivity and perceived effectiveness. One hundred and three police-officers representing the seven French police special units replied to a questionnaire. The results show that perceived effectiveness is positively related to task reflexivity and transactive memory. The relationship between task reflexivity and perceived effectiveness is mediated by the integrated component of transactive memory (bootSE = 0.05, 95% BCa CI [0.004, 0.19]). The theoretical and practical implications are discussed with regard to the development of debriefing methods and teamwork training for the development of shared mental models.  相似文献   
57.
58.
为探讨专业认同、学业情绪与大学生抑郁之间的关系,采用大学生专业认同问卷、青少年学业情绪问卷与抑郁自评量表对329名大学生进行调查。结果发现:(1)专业认同对大学生抑郁有显著负向预测作用;(2)专业认同对积极学业情绪均有显著正向预测作用,但只对消极低唤醒学业情绪有显著负向预测作用;(3)在专业认同对抑郁的影响中,积极低唤醒与消极低唤醒学业情绪起到完全中介作用。结果表明,专业认同对大学生抑郁的影响实际上是一种“温水煮青蛙”效应。  相似文献   
59.
以498名高中生为研究对象,通过问卷调查法探讨高中生的自我妨碍与学习投入的关系,并考察学业浮力的中介作用以及父母支持的调节作用。测量工具包括自我妨碍量表、学习投入量表、学业浮力量表和父母自主支持量表。结果表明:(1)自我妨碍对学习投入有显著负向预测作用;(2)学业浮力在自我妨碍和学习投入的关系中起部分中介作用;(3)自我妨碍和学习投入的关系受到父母支持的调节。与低父母支持相比,在高父母支持的学生中,自我妨碍对学习投入有更强的负向预测作用。  相似文献   
60.
以756名中学生为研究对象,对学业投入、学业成就、同伴团体进行追踪测量,探讨青少年同伴团体的学业投入及学业成就是否存在同伴选择与同伴影响效应。结果表明:(1)在1年的追踪时间中,青少年学业投入的发展呈下降趋势,初始水平与下降速度负相关,学业成就的发展呈上升趋势,初始水平与上升速度无显著相关;(2)学业投入与学业成就存在同伴选择效应,青少年倾向选择与自己学业投入及学业成就相似的个体构建同伴团体;(3)青少年的学业投入及学业成就与同伴逐渐趋近相似,即同伴影响效应显著。  相似文献   
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