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71.
李学勤先生所著《周易溯源》,是以"二重证据法"研究《周易》的典范。《周易溯源》主要对《周易》经传的年代、筮法、帛书《周易》经传以及《易纬》进行讨论,相关结论和方法不但推动了《周易》研究,而且对整个中国古代文化史的研究都有重要意义。 相似文献
72.
Chuanji Gao Timm Rosburg Mingzhu Hou Bingbing Li Xin Xiao Chunyan Guo 《Cognitive, affective & behavioral neuroscience》2016,16(6):977-990
The effectiveness of retrieval practice for aiding long-term memory, referred to as the testing effect, has been widely demonstrated. However, the specific neurocognitive mechanisms underlying this phenomenon remain unclear. In the present study, we sought to explore the role of pre-retrieval processes at initial testing on later recognition performance by using event-related potentials (ERPs). Subjects studied two lists of words (Chinese characters) and then performed a recognition task or a source memory task, or restudied the word lists. At the end of the experiment, subjects received a final recognition test based on the remember–know paradigm. Behaviorally, initial testing (active retrieval) enhanced memory retention relative to restudying (passive retrieval). The retrieval mode at initial testing was indexed by more positive-going ERPs for unstudied items in the active-retrieval tasks than in passive retrieval from 300 to 900 ms. Follow-up analyses showed that the magnitude of the early ERP retrieval mode effect (300–500 ms) was predictive of the behavioral testing effect later on. In addition, the ERPs for correctly rejected new items during initial testing differed between the two active-retrieval tasks from 500 to 900 ms, and this ERP retrieval orientation effect predicted differential behavioral testing gains between the two active-retrieval conditions. Our findings confirm that initial testing promotes later retrieval relative to restudying, and they further suggest that adopting pre-retrieval processing in the forms of retrieval mode and retrieval orientation might contribute to these memory enhancements. 相似文献
73.
Computational algorithms of image processing were developed and evaluated to select, by motion detection, images of resting
artificial pigs and to segment the pigs (mixture of black and white pigs) from their background. Motion detection of the pigs
was implemented by detecting interframe differences of postural behavioral images. This algorithm combines the advantages
of likelihood ratio method and shading model method and shows a stable performance under noisy and dynamic illumination conditions.
Segmentation of the pigs from their background was implemented by employing multilevel thresholding and background reference
techniques. The algorithm automatically determines the number of thresholds needed and produces satisfactory segmentation
when both black and white pigs with different image intensities are present at the same time (the most complicated situation).
The reference background image is updated so that temporal changes in illumination and/or spatial changes of the pen condition
have little effect on the performance of image segmentation. The algorithm employs statistical models of the pigs and background
and Bayes hypothesis testing to obtain and update the exposed portion of the reference background. Linear filters were used
in this process for updating the parameters. These algorithms will serve as essential components for a novel, behavior-based,
interactive approach to assess and control thermal comfort of group-housed pigs, which is expected to result in enhanced animal
health and well-being. 相似文献
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以习近平同志为核心的党中央倡导社会主义核心价值观入法入规,重新阐释了人类道德价值的内容、形式与机制。从伦理内容创新上看,社会主义核心价值观入法入规为传统德主刑辅思想注入新的伦理思想,刷新了“德”与“法”的内涵与外延;从伦理思维范式上看,社会主义核心价值观入法入规实现了德与法的深度融合;从伦理运行机制来看,社会主义核心价值观入法入规确立了将伦理价值与法律价值相结合的评价机制,激活了“德治”软实力与“法治”硬实力共同发力的动力机制。 相似文献
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Yanlou Liu Tao Xin Björn Andersson Wei Tian 《The British journal of mathematical and statistical psychology》2019,72(1):18-37
Two new methods to estimate the asymptotic covariance matrix for marginal maximum likelihood estimation of cognitive diagnosis models (CDMs), the inverse of the observed information matrix and the sandwich-type estimator, are introduced. Unlike several previous covariance matrix estimators, the new methods take into account both the item and structural parameters. The relationships between the observed information matrix, the empirical cross-product information matrix, the sandwich-type covariance matrix and the two approaches proposed by de la Torre (2009, J. Educ. Behav. Stat., 34, 115) are discussed. Simulation results show that, for a correctly specified CDM and Q-matrix or with a slightly misspecified probability model, the observed information matrix and the sandwich-type covariance matrix exhibit good performance with respect to providing consistent standard errors of item parameter estimates. However, with substantial model misspecification only the sandwich-type covariance matrix exhibits robust performance. 相似文献
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基于分部评分模型的思路, 本文提出了一般化的分部评分认知诊断模型(General Partial Credit Diagnostic Model, GPCDM), 与国际上已有的基于分部评分模型思路的多级评分模型GDM (von Davier, 2008 )和PC-DINA (de la Torre, 2012 )相比, GPCDM的Q矩阵定义更加灵活, 项目参数的约束条件更少。Monte Carlo实验研究表明, GPCDM模型的参数估计精度指标RMSE介于[0.015, 0.043], 表明估计精度尚可; TIMSS (2007)实证数据应用研究表明, 与GDM和PC-DINA模型相比, GPCDM与该数据的拟合度更好, 并且使用GPCDM分析该数据的诊断效果也更优。总之, 本研究提供了一种约束条件更少、功能更为强大的多级评分认知诊断模型。 相似文献