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861.
Several studies have clearly shown that texting on a mobile phone increases crash risk (e.g. Dingus et al., 2006; Victor et al., 2014). However, the frequency of texting while driving still remains high (e.g. Vollrath, Huemer, Teller & Likhacheva, 2016). One reason may be that drivers are convinced that they are able to manage this dual task due to their competency in driving and texting. From a theoretical point of view, this may be true within limits – two well-learned, automatically processed tasks may require so few resources most of the time that interferences may not occur.In order to test this assumption, a study with a standardized driving simulator task (the lane change task, LCT; Mattes, 2003) was done with n = 40 drivers selected for their driving experience and tested for their texting abilities. The effect of driving experience (high vs. low) and texting competence (high vs. low) on driving performance was examined in single (driving only) and dual-task (driving and texting) conditions. Additionally, a subjective assessment of one’s task performance was obtained. Texting on the mobile phone significantly impaired driving performance. While driving experience did not have an influence, the deteriorating effect of texting was significantly less pronounced in highly competent phone users. Interestingly, this objective effect was not found in the subjective assessment. Drivers with a high texting competence felt as impaired as drivers with a low texting competence. This is in line with the finding that even in this simple driving task their performance was still significantly deteriorated as compared to driving, only. Thus, it seems that the reason why people text while driving is not that they are not aware of the performance loss. However, this awareness of the possible risk does not seem sufficient to prevent them from texting while driving.  相似文献   
862.
Driver support features (DSF) have the potential to improve safety, but they also change the driver-vehicle relationship —as well as their respective roles and responsibilities. To maximize safety, it is important to understand how drivers’ knowledge and understanding of these technologies—referred to as drivers’ mental models—impact performance and safety. This simulator study examined how drivers with different mental models of adaptive cruise control performed in edge cases. The study compared the responses of groups of drivers, with strong and weak mental models of ACC, established through a combination of screening, training, and exposure, in edge case situations in a high-fidelity driving simulator. In general, participants with strong mental models were faster than those with weak mental models to respond in edge-case situations—defined as cases where the ACC did not detect an approaching object, such as a slow-moving motorcycle. The performance deficits observed for drivers with weak mental models appear to reflect uncertainty surrounding how ACC will behave in edge cases.  相似文献   
863.
Elite swimmers are individual athletes competing mostly on their own. However, when competing in a relay team, they are exposed to social influences possibly leading to effort gains compared to their individual performance. This study investigated effort gains in relay team members during 4 × 100 m freestyle races of Olympic Games and World Championships across the past 20 years. We assumed increasing effort gains in swimmers competing on later serial positions within their relay team since weaknesses in their performances can increasingly less be compensated by their teammates (social indispensability). Furthermore, we assumed a stronger gain in female athletes since females have been shown to be more affected by social indispensability then males. Using linear mixed modelling analyses, we additionally examined the moderating impact of the relay team outcome (i.e. medal-winning chance) on effort gains and indispensability effects while accounting for current team rankings at change-over. Except for the first swimmer, overall effort gains in relay performances were found as compared to performances in individual races during the same championship. Furthermore, these gains were close to equally distributed among both laps of the 100 m distance. However, even though effort gains are tending to be most pronounced for the last relay team swimmer we failed to detect any significant indispensability effect in our data set. Noteworthy, female swimmers showed larger effort gains when winning a medal (based on the current team rankings) was likely. In contrast, males showed effort gains irrespective of the serial order within the relay team and medal chance. Consequently, tentative recommendations are derived on how to line up a relay team.  相似文献   
864.
For many athletes, retirement from higher levels of competitive sport poses significant challenges. Research has shown that athletic identity is a key predictor of adjustment trajectories, but the mechanisms through which this affects outcomes are less clear. Added to this, there has been limited research on the role that wider social identities, and the resources they enable, play in adjustment. Addressing both these issues, we examined theoretically derived social identity pathways to retirement adjustment in athletes who had played sport at higher competitive levels and two potential mechanisms, or psychological resources, through which adjustment might be enabled. This was examined in two samples: retired athletes from countries in Western (n = 215) and Eastern (n = 183) regions. Loss of athletic identity, social group memberships (multiple, maintained and new), psychological resources (perceived meaning in life and control), and adjustment (life satisfaction, depression, and perceived physical health) were assessed. In both samples, the loss of athletic identity undermined adjustment by reducing meaning in life and perceived control. Path analysis showed that both maintained and gained social group memberships counteracted the negative effects of athletic identity loss on adjustment. Evidence that these pathways enabled access to psychological resources was found primarily in Chinese athletes, with maintained groups influencing personal control and new groups influencing meaning in life. These findings highlight the importance of social identity processes to retirement from higher levels of competitive sport and the mechanisms through which they can either support or undermine adjustment.  相似文献   
865.
ABSTRACT

Unsteady-state upward solidification experiment was carried out with the Al-3Cu-3Ni (wt.%) alloy. Temperature profiles were obtained through a water-cooled directional solidification device. Analysis on the resulting as-cast microstructure and its adaptation to thermal solidification parameter, such as growth and cooling rates and solidification local time, VL, TR and tSL, respectively, was carried out. The results showed that the resulting microstructure is constituted by an Al-rich primary phase (Al α ), characterised by a dendritic network, and by second phases that take place within the interdendritic regions, forming a eutectic mixture composed by the β-Al3Ni?+?θ-Al2Cu intermetallic compounds (IMCs), whose size and morphology have been affected by VL and TR. The length of the microstructural scale of the Al α phase was measured by the secondary dendritic spacing (λ 2). The experimental mathematical expression of λ 2 obtained in this work was compared with mathematical models proposed in the literature that associate tSL-λ 2 for non-equilibrium and equilibrium solidification conditions.  相似文献   
866.
What we are witnessing in the present time in human history, in the 2020’s, is a vortex of intersecting pandemics – jolting revelations that are unfolding with a terrific energy and force – so much so that we cannot ignore them or escape them. These include the world-wide pandemics of racism, COVID-19 and climate change. This paper argues that all of these swirling pandemics are manifestations of the archetype of the apocalypse, which is constellating now in a very powerful way. Any one of these phenomena could swallow humanity whole as a species. Together they represent a seemingly overwhelming challenge for us to meet over the next century of life on earth. If humanity cannot meet the challenge of these combined negative forces, it could simply perish. A multi-layered intersecting set of challenges such as this has never yet occurred in human history. We must therefore be very alert to what is going on, and as to how we can consciously mediate these threats, both individually and collectively. It also presents an unprecedented opportunity for humanity to evolve and grow psychologically both individually and collectively, nationally and globally.  相似文献   
867.
To acknowledge the significance of contexts for personality, this study focused on personality in romantic relationships and the concept of relationship-specific traits. Specifically, we were interested in how relationship-specific traits (i.e., how people report to be in their relationship) relate to generalized Big Five traits, and whether both constructs codevelop over time. We computed dyadic bivariate latent growth curve models, using data from 551 couples (Mage = 32.23 years) over 1 year. The findings indicated that generalized traits and relationship-specific traits were positively correlated in their intercepts but did not codevelop over time. Furthermore, baseline relationship satisfaction explained variance in traits, particularly in relationship-specific traits. These findings have implications for how to study personality development in the romantic relationship context.  相似文献   
868.
In between-item multidimensional item response models, it is often desirable to compare individual latent trait estimates across dimensions. These comparisons are only justified if the model dimensions are scaled relative to each other. Traditionally, this scaling is done using approaches such as standardization—fixing the latent mean and standard deviation to 0 and 1 for all dimensions. However, approaches such as standardization do not guarantee that Rasch model properties hold across dimensions. Specifically, for between-item multidimensional Rasch family models, the unique ordering of items holds within dimensions, but not across dimensions. Previously, Feuerstahler and Wilson described the concept of scale alignment, which aims to enforce the unique ordering of items across dimensions by linearly transforming item parameters within dimensions. In this article, we extend the concept of scale alignment to the between-item multidimensional partial credit model and to models fit using incomplete data. We illustrate this method in the context of the Kindergarten Individual Development Survey (KIDS), a multidimensional survey of kindergarten readiness used in the state of Illinois. We also present simulation results that demonstrate the effectiveness of scale alignment in the context of polytomous item response models and missing data.  相似文献   
869.
Recent work finds that the sense of solidarity some whites feel with their racial group is strongly associated with their political attitudes, particularly since the election of Barack Obama. Prior work has also noted that levels of this identity have been stable across time and data sources. We, however, document a notable decline in levels of white identity in both panel and cross-sectional national survey data immediately after the 2016 presidential election. Using a two-wave panel design, we examine the factors associated with this decline. We examine whether particular emotional reactions, especially disgust toward Donald Trump, pushed some whites away from their racial identity. We also consider the possibility that some whites may have felt that Trump's election reduced perceptions of racial or political threat, therefore lowering levels of white identity. We find the strongest support for the former hypothesis; the decline in white identity was driven mostly by whites expressing disgust toward Trump. Our results highlight the effect that the political environment can have on group identities and point in particular to the significant role that disgust may play in attenuating the strength of group solidarity.  相似文献   
870.
辛素飞  梁鑫  盛靓  赵智睿 《心理学报》2021,53(8):875-889
教师主观幸福感作为衡量教师群体心理健康状况的一项关键指标, 对其现状的调查和分析至关重要, 同时, 对其随社会变迁的动态变化趋势、及其与社会变迁的关系的监测也不可忽视。本研究对2002至2019年间的51篇采用总体幸福感量表(GWB)测量教师主观幸福感的研究报告(共包括13600名教师)进行横断历史的元分析。研究发现:(1)教师主观幸福感均值与年代呈显著负相关, 这说明我国教师主观幸福感在逐年下降。(2)来自社会经济条件(居民消费水平、房价、老年抚养比和教育经费)、社会联结(家庭规模数、离婚率和城镇化水平)和社会威胁(犯罪率)三方面的8项宏观社会指标的变化能显著预测教师主观幸福感的下降。(3)中小学教师的主观幸福感随年代下降的趋势更明显, 其主观幸福感得分要显著低于高校教师。本研究不仅探究了我国教师主观幸福感近20年的变迁趋势, 而且结合社会宏观发展的指标, 提出了影响我国教师主观幸福感的三维理论框架, 对群体社会心理的研究思路进行了纵向(随时代变迁)及横向(宏观社会指标)的拉伸, 拓展理论基础的同时, 在实践上, 为干预调节我国教师群体主观幸福感提供决策依据。  相似文献   
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