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   759篇
  免费   89篇
  国内免费   275篇
  2024年   1篇
  2023年   27篇
  2022年   43篇
  2021年   70篇
  2020年   68篇
  2019年   72篇
  2018年   77篇
  2017年   62篇
  2016年   69篇
  2015年   52篇
  2014年   57篇
  2013年   96篇
  2012年   39篇
  2011年   34篇
  2010年   36篇
  2009年   32篇
  2008年   43篇
  2007年   30篇
  2006年   41篇
  2005年   39篇
  2004年   20篇
  2003年   15篇
  2002年   10篇
  2001年   16篇
  2000年   8篇
  1999年   6篇
  1998年   12篇
  1997年   9篇
  1996年   8篇
  1995年   5篇
  1994年   6篇
  1993年   5篇
  1992年   6篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1985年   1篇
  1977年   1篇
排序方式: 共有1123条查询结果,搜索用时 15 毫秒
131.
In his book, The Rise of Christianity, Rodney Stark argues that the early Christian church indirectly benefitted from the plagues that struck the early Roman Empire in the 2nd and 3rd centuries of the Common Era. In particular, he argues that the early church's doctrines concerning love, charity, and social service would have led Christians to enjoy higher survival rates than pagans, which would have left the social networks of the former relatively intact, while those of the latter in disarray. Moreover, since recruitment to new religious movements occurs largely through social ties, the probability that an average pagan would have converted to Christianity would have been greater after the plagues than before. In this article, we use computer modeling to test Stark's hypothesis. Not only do we find support for his hypothesis, we also show that higher survival rates for either group not only would have benefitted their respective social networks but also would have benefitted their competitor's social networks, highlighting how network effects often flow in multiple and unexpected ways. We conclude with suggestions for future research, in particular how scholars can build upon our analyses and explore alternative assumptions.  相似文献   
132.
The attention network test (ANT) assesses efficiency across alerting, orienting, and executive components of visual attention. This study examined approaches to assessing auditory attention networks, and performance was compared to the visual ANT. Results showed (1) alerting was sufficiently elicited in a pitch discrimination and sound localization task, although these effects were unrelated, (2) weak orienting of attention was elicited through pitch discrimination, which varied based on ISI and conflict level, but robust orienting of attention was found through sound localization, and (3) executive control was sufficiently assessed in both pitch discrimination and sound localization tasks, but these effects were unrelated. Correlation analysis suggested that, unlike alerting and orienting, sound localization auditory executive control functions tap a shared attention network system. Overall, the results suggest that auditory ANT measures are largely task and modality specific, with sound localization offering potential to assess all three attention networks in a single task.  相似文献   
133.
The evolutionary theory of behavior dynamics is a complexity theory that instantiates the Darwinian principles of selection, reproduction, and mutation in a genetic algorithm. The algorithm is used to animate artificial organisms that behave continuously in time and can be placed in any experimental environment. The present paper is an update on the status of the theory. It includes a summary of the evidence supporting the theory, a list of the theory's untested predictions, and a discussion of how the algorithmic operations of the theory may correspond to material reality. Based on the evidence reviewed here, the evolutionary theory appears to be a strong candidate for a comprehensive theory of adaptive behavior.  相似文献   
134.
The negativity bias is the tendency for individuals to give greater weight, and often exhibit more rapid and extreme responses, to negative than positive information. Using the Deese-Roediger-McDermott illusory memory paradigm, the current study sought to examine how the negativity bias might affect both correct recognition for negative and positive words and false recognition for associated critical lures, as well as how trait neuroticism might moderate these effects. In two experiments, participants studied lists of words composed of semantic associates of an unpresented word (the critical lure). Half of the lists were comprised of positive words and half were comprised of negative words. As expected, individuals remembered negative list words better than positive list words, consistent with a negativity bias in correct recognition. When tested immediately (Experiment 1), individuals also exhibited greater false memory for negative versus positive critical lures. When tested after a 24-hr delay (Experiment 2), individuals higher in neuroticism maintained greater false memory for negative versus positive critical lures, but those lower in neuroticism showed no difference in false memory between negative and positive critical lures. Possible mechanisms and implications for mental health disorders are discussed.  相似文献   
135.
IntroductionPostural instability during walking and tripping over obstacles are the main causes of falls in people with Parkinson’s disease (PD). Preliminary limited evidence suggests that the length of the prospective follow-up period affects falls prediction in PD, with shorter periods leading to more accurate prediction. Thus, the primary aim of the present study was to test the performance of center of pressure (CoP) variables during obstacle crossing to predict fall risk in people with PD during subsequent periods of four, six, and 12 months. We also compared CoP variables during obstacle crossing between fallers and non-fallers.MethodsForty-two individuals with PD, in mild to moderate stages, completed the baseline obstacle crossing assessment and reported falls for 12 months. Participants walked at their self-selected pace and were instructed to cross an obstacle (half knee height) positioned in the middle of an 8-m long pathway. A force platform was used to analyze CoP parameters of the stance phase of the trailing limb (most affected limb). The ability of each outcome measure to predict fall risk at four, six, and 12 months was assessed using receiver operating characteristic curve analyses.ResultsTen individuals (23.8%) were considered fallers at four months, twelve individuals (28.5%) at six months, and twenty-one individuals (50%) at 12 months. CoP amplitude and CoP velocity in the mediolateral direction significantly predicted fall risk at four, six, and 12 months. As judged by the area under the curve, mediolateral CoP velocity showed the best performance at four months, while mediolateral CoP amplitude showed the best performance at six months. Fallers presented greater values of mediolateral CoP velocity and amplitude than non-fallers.ConclusionThese findings suggest that mediolateral CoP velocity and amplitude during obstacle crossing might be useful to predict fall risk in people with PD. Therefore, larger studies are encouraged.  相似文献   
136.
137.
138.
Detecting in prior bearing faults is an essential task of machine health monitoring because bearings are the vital components of rotary machines. The performance of traditional intelligent fault diagnosis methods depend on feature extraction of fault signals, which requires signal processing techniques, expert knowledge, and human labor. Recently, deep learning algorithms have been applied widely in machine health monitoring. With the capacity of automatically learning complex features of input data, deep learning architectures have great potential to overcome drawbacks of traditional intelligent fault diagnosis. This paper proposes a method for diagnosing bearing faults based on a deep structure of convolutional neural network. Using vibration signals directly as input data, the proposed method is an automatic fault diagnosis system which does not require any feature extraction techniques and achieves very high accuracy and robustness under noisy environments.  相似文献   
139.
People are becoming more and more humanized in the process of understanding the law. According to the right to discipline, the law has its own core setting factors, while some limits can't reach people's desire. Therefore, the legal and illegal mode of transcending rights is very important. In order to analyze the legal form of modern rights, in this paper, the cognitive learning and memory process of human brain were simulated through the artificial neural network and the understanding of human brain structure, and the role of law, discipline and governance was reflected. In the study, the structure and algorithm of the model neural network were optimized, the memory forgetting curve mechanism that can simulate the human brain was introduced, and thus the network recognition rate was improved. And in the algorithm, the calculation of matching degree was avoided, and the computational complexity was reduced to the sample. Then the sample was compared with the SOM, ART1, and PNN algorithms. The experimental simulation results show that the recognition speed of this sample is 1.9 times faster than that of ART1, 58 times than that of SOM, and 1.5 times than that of the PNN network.  相似文献   
140.
为探明个体对自我信息的反应抑制神经机制,记录了被试在完成面孔识别的停止信号任务时的脑电信号。神经振荡结果显示,反应任务中,加工自我面孔引发了更大的同步化δ节律和去同步化β节律;停止任务中,自我面孔引发了更大的去同步化β节律,特别在大脑前额区和中线上。表明,自我信息的反应抑制优势发生在抑制控制阶段,在于增强的β节律的去同步化促进了运动准备,提高了后续的动作抑制的速度。  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