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231.
"道"是老子哲学体系中的核心,老子不仅提出虚空的道是宇宙的本体,是无法用语言来描述的,而且说明道是混成之物,即道是有精妙的内部结构属性的,并从不同的侧面说明了认识"道"是混成之物的路径。道是由无限创生因子混融而成的系统,宇宙在创生及万物演化的过程中,道或无限的创生因子始终起着根本性的作用,即宇宙间的一切事物现象都是道所为。道是由创生因子混融而成的思想观点,可为现代宇宙论的发展提供新的思维维度,为科学探索真空世界的奥秘提供新的研究途径,推进现代宇宙学的进步。  相似文献   
232.
以自我参照加工任务为范式,实验采用事件相关电位(ERP)技术,探讨了自我参照加工中符合判断和不符合判断加工的时间进程和大脑神经机制。结果发现,自我参照加工在时间上可以概括分为三个阶段:注意分配阶段N1(80~150 ms)波幅出现自我参照结果的差异;语义整合阶段N2(250~450 ms)波幅和潜伏期出现自我参照结果的差异;评价判断阶段P3(450~700 ms)波幅和潜伏期出现自我参照结果的差异。从我们选择的大脑兴趣区激活水平上分析发现,自我信息在大脑中的激活似乎是一个由右及左,由后及前再及后的动态变化过程。研究结果丰富了自我参照加工的已有结果,并且对未来研究具有一定的启示意义。  相似文献   
233.
For bulk piezoelectric ceramics plates, the fundamental thickness-stretch (TSt) waves are always coupled to the in-plane extension waves and the symmetric thickness-shear waves. The occurrence of these spurious modes in bulk piezoelectric ceramics plates is undesirable as it may interfere with the operation of transducers. 1–3 piezoelectric composites are promising candidates to suppress the spurious modes mentioned above. However, theoretical modelling of multiphase ceramic composite objects is very complex. In this study, a simple analytical TSt vibration model is constructed from three-dimensional equations of linear piezoelectricity. The mechanical damping is considered in the model by introducing a complex elastic constant. The performance of 1–3 piezoelectric composites is analysed and the electrical impedance results from theoretical and experimental analysis are compared. The results show that there is excellent agreement between the experimental electrical impedance and that obtained by the theoretical TSt vibration analysis. This indicates that 1–3 piezoelectric composites can be operated in a nearly pure TSt vibration mode near the fundamental resonance. The analytical model we present is valid for analysing 1–3 piezoelectric composites plates with large aspect ratios quickly and efficiently.  相似文献   
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Previous research has contrasted patterns of cautious or prevention‐oriented relationality in various West African settings with patterns of growth or promotion‐oriented relationality in many North American settings. The present research draws upon the concept of relational mobility to test the hypothesis that different patterns of relationality have their source in respective affordances for embedded interdependence or abstracted independence. Study 1 investigated the relationship between cautious intimacy and perception of relational mobility among a sample of Hong Kong students. Study 2 compared students in Hong Kong and North American settings to test whether differences in perception of relational mobility mediated the hypothesized differences in caution about friends. Study 3 used an experimental manipulation among a sample of Hong Kong students to test the hypothesis that increased perception of relational mobility reduces caution about friends. Results reveal broad support for the hypotheses. Whether as a measured variable or as an experimental treatment, the perception of relational mobility was negatively related to caution about friends. Moreover, this relationship mediated hypothesized cross‐national differences in caution about friendship. A discussion of the results considers intersections of cultural and ecological approaches to psychology and implications for theoretical conceptions of interdependence.  相似文献   
236.
In this 8‐year longitudinal study, we traced the vocabulary growth of Chinese children, explored potential precursors of vocabulary knowledge, and investigated how vocabulary growth predicted future reading skills. Two hundred and sixty‐four (264) native Chinese children from Beijing were measured on a variety of reading and language tasks over 8 years. Between the ages of 4 to 10 years, they were administered tasks of vocabulary and related cognitive skills. At age 11, comprehensive reading skills, including character recognition, reading fluency, and reading comprehension were examined. Individual differences in vocabulary developmental profiles were estimated using the intercept‐slope cluster method. Vocabulary development was then examined in relation to later reading outcomes. Three subgroups of lexical growth were classified, namely high‐high (with a large initial vocabulary size and a fast growth rate), low‐high (with a small initial vocabulary size and a fast growth rate) and low‐low (with a small initial vocabulary size and a slow growth rate) groups. Low‐high and low‐low groups were distinguishable mostly through phonological skills, morphological skills and other reading‐related cognitive skills. Childhood vocabulary development (using intercept and slope) explained subsequent reading skills. Findings suggest that language‐related and reading‐related cognitive skills differ among groups with different developmental trajectories of vocabulary, and the initial size and growth rate of vocabulary may be two predictors for later reading development.  相似文献   
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238.
Causally related concepts like “virus” and “epidemic” and general associatively related concepts like “ring” and “emerald” are represented and accessed separately. The Evoked Response Potential (ERP) procedure was used to examine the representations of causal judgment and associative judgment in semantic memory. Participants were required to remember a task cue (causal or associative) presented at the beginning of each trial, and assess whether the relationship between subsequently presented words matched the initial task cue. The ERP data showed that an N400 effect (250–450 ms) was more negative for unrelated words than for all related words. Furthermore, the N400 effect elicited by causal relations was more positive than for associative relations in causal cue condition, whereas no significant difference was found in the associative cue condition. The centrally distributed late ERP component (650–750 ms) elicited by the causal cue condition was more positive than for the associative cue condition. These results suggested that the processing of causal judgment and associative judgment in semantic memory recruited different degrees of attentional and executive resources.  相似文献   
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240.
For comparing nested covariance structure models, the standard procedure is the likelihood ratio test of the difference in fit, where the null hypothesis is that the models fit identically in the population. A procedure for determining statistical power of this test is presented where effect size is based on a specified difference in overall fit of the models. A modification of the standard null hypothesis of zero difference in fit is proposed allowing for testing an interval hypothesis that the difference in fit between models is small, rather than zero. These developments are combined yielding a procedure for estimating power of a test of a null hypothesis of small difference in fit versus an alternative hypothesis of larger difference.  相似文献   
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