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   2557篇
  免费   303篇
  国内免费   169篇
  2024年   9篇
  2023年   83篇
  2022年   50篇
  2021年   104篇
  2020年   135篇
  2019年   121篇
  2018年   144篇
  2017年   134篇
  2016年   162篇
  2015年   102篇
  2014年   129篇
  2013年   373篇
  2012年   64篇
  2011年   114篇
  2010年   66篇
  2009年   99篇
  2008年   112篇
  2007年   116篇
  2006年   94篇
  2005年   97篇
  2004年   80篇
  2003年   89篇
  2002年   58篇
  2001年   50篇
  2000年   44篇
  1999年   49篇
  1998年   35篇
  1997年   38篇
  1996年   27篇
  1995年   24篇
  1994年   21篇
  1993年   24篇
  1992年   17篇
  1991年   18篇
  1990年   17篇
  1989年   13篇
  1988年   13篇
  1987年   12篇
  1986年   12篇
  1985年   7篇
  1984年   6篇
  1983年   9篇
  1982年   7篇
  1981年   10篇
  1980年   9篇
  1979年   9篇
  1978年   8篇
  1977年   9篇
  1976年   6篇
排序方式: 共有3029条查询结果,搜索用时 15 毫秒
81.
Traditional research on post-traumatic growth has utilized methodologically flawed cross-sectional designs that involve retrospective assessments of post-traumatic growth. This has resulted in a majority of research in this field suffering from a lack of credibility and reliability. In this special issue, we present nine articles that seek to make innovative conceptual and methodological contributions with the goal of promoting better research practices on post-traumatic growth. In the introduction to this special issue, we provide an overview of these contributions, and discuss the implications of these articles both to improving future scholarship and to encouraging personality scientists to examine this important phenomenon in the years and decades to come.  相似文献   
82.
为考察初中生友谊质量与孤独感的变化轨迹及两者间的关系,采用关系网络问卷、孤独感量表对西安市的875名初中生(M=12.73±0.18;男生494名)进行三年追踪测量,使用多元潜变量增长模型进行分析。结果发现:(1)初中三年,中学生的友谊质量逐渐提高,孤独感水平逐渐下降;(2)初一时的友谊质量和孤独感水平存在显著的个体差异,初中三年期间二者的发展速度也存在个体差异;(3)初一时的友谊质量可显著预测初一时的孤独感水平(β=-1.77,p<0.001)及随后的发展速度(β=0.20,p<0.05);(4)男生的孤独感水平初始值高于女生,友谊质量的初始值则低于女生;高SES个体孤独感的起始值高于低SES个体。本研究结果揭示了初中三年期间个体友谊质量与孤独感的动态变化关系及友谊质量对孤独感的预测作用,对改善青少年孤独感的现状有一定的现实指导意义。  相似文献   
83.
Perceptual judgments result from a dynamic process, but little is known about the dynamics of number-line estimation. A recent study proposed a computational model that combined a model of trial-to-trial changes with a model for the internal scaling of discrete numbers. Here, we tested a surprising prediction of the model—a situation in which children's estimates of numerosity would be better than those of adults. Consistent with the model simulations, task contexts led to a clear developmental reversal: children made more adult-like, linear estimates when to-be-estimated numbers were descending over trials (i.e., backward condition), whereas adults became more like children with logarithmic estimates when numbers were ascending (i.e., forward condition). In addition, adults’ estimates were subject to inter-trial differences regardless of stimulus order. In contrast, children were not able to use the trial-to-trial dynamics unless stimuli varied systematically, indicating the limited cognitive capacity for dynamic updates. Together, the model adequately predicts both developmental and trial-to-trial changes in number-line tasks.  相似文献   
84.
价值观是人们区分好坏、善恶、美丑、损益、是非的信念系统,通常是充满情感的。价值观具有稳定性与可变性的特点。价值观的稳定性表现为:基本价值观具有跨时间的稳定性和跨情境的一致性; 特别是保护性价值观和人生价值观具有较强的稳定性。个人的发展、经历重大事件以及实验干预可导致价值观的改变,可变性主要表现为价值观的重要性发生变化。从我国的实际出发,探讨个人的核心价值观问题、以及价值观研究中国化、价值观研究对价值观教育的启示,乃是我们今后研究的关注点。  相似文献   
85.
Traffic congestion and crash rates can be reduced by introducing variable speed limits (VSLs) and automatic incident detection (AID) systems. Previous findings based on loop detector measurements have revealed that drivers reduce their speeds while approaching traffic congestion when the AID system is active. Notwithstanding these behavioural effects, most microscopic traffic flow models assessing the impact of VSLs do not describe driver response accurately.This study analyses the main factors that influence driver deceleration behaviour while approaching traffic congestion with and without VSLs. The Dutch VSL database was linked to the driver behaviour data collected in the UDRIVE naturalistic driving study. Driver engagement in secondary tasks and glance behaviour were extracted from the video data. Linear mixed-effects models predicting the characteristics of deceleration events were estimated.The results show that the maximum deceleration is high when approaching a slower leader, when driving at high speeds and short distance headways, and close to the beginning of traffic congestion. The minimum time headway is short when driving at high speeds and changing lanes. Certain drivers showed higher decelerations and shorter time headways than others. Controlled for these main factors, smaller maximum decelerations were found when the VSLs were present and visible, and when the gantries were within close proximity. These factors could be incorporated into microscopic traffic simulations to evaluate the impact of AID systems on traffic congestion more realistically. Further research is needed to clarify the link between engagement in secondary tasks, glance behaviour and deceleration behaviour.  相似文献   
86.
Autonomous Vehicle (AV) research has focused on public acceptance of and intention to use AVs, with trust emerging as important to these variables. Research on AV trust has centered on trust in vehicle performance. However, trust evaluation may include AV manufacturers and developers, and regulation pertaining to AVs; thus, we expand our measurement of trust to include beliefs based on manufacturers and regulation. In this experiment, we manipulate information regarding manufacturer focus (i.e., an emphasis on standards, regulations, and research (SRR) versus speed to market) to determine its effect on trust. When information focused on SRR, we found higher levels of trust in AV performance and in manufacturers, compared to when it focused on speed to market. In addition, information regarding passenger control (i.e., the ability to take over for the vehicle and to determine privacy settings) was manipulated to yield either high or low passenger control conditions. Behavioral Intention (BI) to use AVs was lowest when speed to market was emphasized and when passenger control was low. Furthermore, trust was tested as a mediator between perceived risk and BI. Trust in AV performance partially mediated the relationship between perceived AV performance risk and BI. In addition, trust in AV regulation partially mediated the relationship between AV privacy/security risk and BI. Researchers should continue to examine trust beyond the AV itself to encompass trust in manufacturers and regulations. Those designing and marketing AVs should carefully consider decisions that influence manufacturer/developer reputation and passenger control due to their effect on intention to use AVs.  相似文献   
87.
The paper presents the formalism of an intelligent decision-making system based on multi-agent neurocognitive architectures, which has an architectural similarity to the human brain. An invariant of the organizational and functional structure of the intellectual decision-making process based on the multi-agent neurocognitive architecture is developed. An algorithm for teaching intelligent decision-making systems based on the self-organization of the invariant of multi-agent neurocognitive architectures is presented. Using this algorithm, an intelligent agent was trained and the architecture of the learning process was built on the basis of an invariant of neurocognitive architecture. Further research is related to training an intelligent agent in more complex behavior and expanding the capabilities of an intelligent decision-making system based on multi-agent neurocognitive architectures.  相似文献   
88.
ObjectivesPoor adherence to nutritional guidance by athletes may compromise their health and performance. Enhancing adherence is therefore an important performance and welfare strategy. The aim of this study was to qualitatively explore the barriers and enablers of elite athletes' adherence to nutritional guidelines.DesignUnderpinned by our constructionist epistemological position and our relativist ontology, we conducted a qualitative study using focus groups.MethodsWe used the Capability, Opportunity, and Motivation Behaviour (COM-B) model and the Theoretical Domains Framework (TDF) to conduct focus group discussions with a purposive sample of 39 UK-based funded athletes (mean age = 23 ± 3.81), participating in either Olympic and Paralympic sport (n = 30) or professional sport (n = 9), who had access to a nutritionist. Data were analysed using reflexive thematic analysis.ResultsAthlete adherence to nutritional guidance was seasonal and included inadequate energy intakes and episodes of binge eating. Underpinning these behaviours, athletes' emotional barriers (motivation) are reinforced through their social interactions within the high-performance environment (opportunity) and athletes' training environment limits developmental opportunities for food planning (capability). However, a holistic-developmental approach by the sports nutritionists (opportunity) supports athlete wellbeing and nutritional adherence.ConclusionThese findings advance theoretical understanding of the barriers and enablers of nutritional adherence amongst elite-level athletes in high-performance sport and present a number of significant implications for athlete support personnel seeking to enhance performance in demanding sporting contexts. Drawing on the Behaviour Change Wheel (BCW), recommendations include the need to 1) train and educate sports nutritionists in human behaviour, 2) update regulations for sports nutrition profession practice to acknowledge the skills required to support athletes' emotional wellbeing, 3), educate coaches on the sensitivity of body weight and composition and develop guidelines for monitoring athletes' body weight and composition in sport, 4) persuade influential leaders to develop culture guidelines that shift the performance-narrative of high-performance (i.e., environmental restructuring).  相似文献   
89.
We explore developmental pathways to excellence in sub-elite adolescent alpine ski racing by exploring athletes' engagement in practice activities that characterize sport specialization and/or diversification. Moreover, we extend previous research by using more refined linear mixed-effects models to examine changes in practice and performance data over time rather than relying on the less sensitive repeated measures ANOVAs typically used in previous research. Altogether, 174 individuals (M = 15.9 yrs, women = 91) from professional development academies in the United States completed a sport-specific Practice History Questionnaire (PHQ). We recorded national rankings in technical events to assess performance. Mixed-effects models indicated that hours in ski-related activities generally increased over time (linear β = 1.38, p's < 0.001), except time spent in play, which decreased over time (β = 102.8, p = 0.002). Performance rankings also improved over time (β = 30.99, p < 0.001), with more time spent in ski-activity associated with greater rates of improvement, particularly in younger skiers (β = 9.77, p's < 0.001). The effects were largely driven by time spent in coach-led group practice (β = 2.16, p < 0.001). Overall, an earlier age of first engagement was associated with better rankings (β = −15.40, p = 0.024), and accumulating more hours in other sports was also associated with greater rates of performance improvement (β = −8.87, p = 0.014). Sub-elite alpine ski racers engage early in the sport, with higher-ranked athletes spending more time in ski-specific practice, particularly group practice, during development. However, these athletes generally continued to participate in other sports across development, providing greater support for the early engagement hypothesis rather than early specialization per se.  相似文献   
90.
认知诊断评估旨在探讨个体内部的知识掌握结构,并提供关于学生优缺点的详细诊断信息,以促进个体的全面发展。当前研究者已开发了大量0-1评分的认知诊断模型,但对于多级评分认知诊断模型的研究还比较少。本文对已有的多级评分认知诊断模型进行了归纳,介绍了模型的假设,计量特征以及适用范围,为实际应用者和研究者在多级评分认知诊断模型的比较和选用上提供借鉴和参考。最后,对未来关于多级评分诊断模型的研究方向进行了展望。  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