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931.
“多少”概念发展的研究   总被引:1,自引:0,他引:1  
采用数量判定任务,分别用2~30和5~100范围内点子图为刺激,研究个体“多”和“少”概念的发展。结果发现:在5~100点子条件下,随年龄的增长,个体“多”概念的判断值、“少”概念的判断值、“多”“少”概念的临界值均显著增大;7~9岁是个体“多少”概念发展的转折期;个体对“多少”概念的认知具有相对性;在本实验的两种条件下,随年龄增长,个体“多”概念的判断值、“少”概念的判断值、“多”“少”概念的临界值逐渐趋于刺激点子数最大值的2/3、1/3、1/2,“多”概念与“少”概念判断的不确定距离逐渐趋于刺激点子数最大变化范围的1/3或略小于1/3。  相似文献   
932.
中国传统女性伦理与礼仪及其现代价值   总被引:1,自引:0,他引:1  
中国传统女性伦理与礼仪内容庞杂,糟粕精华并存。现代女性伦理与礼仪建设应当摒弃其中维护男性特权,束缚女性人身自由的非人道性的糟粕,承继其中具有现代价值的精华,从而建立人道、文明、科学的现代女性伦理与礼仪新体系。  相似文献   
933.
用问卷法对194名初中生学业延迟满足的特点及相关因素进行了研究。结果表明:初中学生的学业延迟满足存在年级和性别差异,初二和初三学生的学业延迟满足水平明显低于初一学生,女生比男生的学业延迟满足能力高。课堂目标结构与学业延迟满足有显著关系,任务取向的课堂目标与学业延迟满足呈正相关关系;自我取向的课堂目标与学业延迟满足呈负相关关系。任务价值、自我效能与学业延迟满足呈正相关关系,学业延迟满足与学业成绩呈正相关关系。  相似文献   
934.
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer.  相似文献   
935.
Owing to their very high strength, nanocrystalline metals have been extensively studied over the recent years. The direct Hall–Petch law, empirically proportioning the material strength to the inverse square root of its grain size has been shown to break down below a grain size of the order of tenths of nanometers. This phenomenon has been widely rationalized as a gradual switch from intragrain mediated deformation mechanisms to grain boundary mediated deformation mechanisms. This transition has been observed in many finite element simulations, despite the intrinsic restriction of necessarily limiting the nanocrystalline representative assembly to only a few grains. Such a limitation is generally overlooked, and its influence on an uniaxial tension test – when compared to a complete sample of millions of grains – ignored. We propose here to quantify the approximation done by considering a finite number of grains by means of a simple analytical model based on the early work of Stevens [R.N. Stevens, Philos. Mag. 23 (1971) p. 265]. The finite element approximation is demonstrated to be relatively good, even down to only three grains in width, and a method to “correct” the stress-strain curves of small representative volumes is proposed.  相似文献   
936.
The relationship between divine and created causality was widely discussed in medieval and early modern philosophy. Contemporary scholars of these discussions typically stake out three possible positions: occasionalism, concurrentism, and mere-conservationism. It is regularly claimed that virtually no medieval thinker adopted the final view which denies that God is an immediate active cause of creaturely actions. The main aim of this paper is to further understanding of the medieval causality debate, and particularly the mere-conservationist position, by analysing Peter John Olivi's neglected defence of it. The paper also includes discussion of Thomas Aquinas's arguments for concurrentism and an analysis of whether Olivi's objections refute his position.  相似文献   
937.
Nowadays, the criticism of the so-called ‘deficit model’ and the need for ‘upstream engagement’ in science and technology are becoming part of the master narratives of public policies in many countries, especially concerning nanotechnology. This may be considered as a major success for STS scholars, whose research results have largely contributed to this change, especially those concerning the GMO controversies. Some STS scholars thus move from a position of distant and critical observers to the role of experts in social engineering or advisers of policy-makers. However, in their enthusiasm concerning the expected benefits of upstream engagement, institutions, TA practitioners and social scientists seem to ignore some important limitations as well as the implicit framing assumptions of the concept. Based on an experience made by a group of social scientists in the Grenoble area—one of the major ‘nanodistricts’ in Europe—our paper shows that the ‘upstream engagement’ concept is still embedded in a linear model of innovation and is not very useful to anyone pursuing the co-production of innovations. It is especially true when socio-technical networks are already aligned by powerful actors and a worldwide agenda as in the case of nanotechnology. In order to give an opportunity for public engagement to have a larger impact on decision-making, we propose an alternative approach, which combines Actor–Network Theory (ANT), as an analytical tool, with the reflexive and ongoing implementation of public participation. Public engagement is probably one of the critical loci where STS scholars must reflect on the articulation between the knowledge they produce and public policies in action.  相似文献   
938.
ABSTRACT

Descartes did not use the terms ‘primary’ and ‘secondary’ qualities, but a similar distinction emerges from his texts: certain qualities of objects (such as size and shape) are intrinsic properties of matter, whereas others (like colours and smells) are products of the interaction with a perceiver. A common interpretation states that the division between primary and secondary qualities is explained by the way in which we are acquainted with them: an idea of a primary quality is similar to its physical causes, and it is clearly and distinctly perceived by the intellect. An idea of a secondary quality is dissimilar to its physical causes and it is obscurely and confusedly perceived by the senses. This view receives the name of ‘bifurcation reading’ (Simmons, A. ‘Descartes on the Cognitive Structure of Sensory Experience’. Philosophy and Phenomenological Research, LXVII, no. 3 (November 2003)). While it integrates well some textual occurrences, it creates a problematic fragmentation within single acts of perception. This paper contends that this reading is incorrect. It presents several arguments for the claim that the distinction of qualities is due to the different ways in which our ideas of them misrepresent their physical causes. Then, Descartes’ dissimilarity thesis between physical objects and our ideas of them remains a structural feature of his theory of sensory perception and not a local phenomenon affecting only ideas of secondary qualities.  相似文献   
939.
Although distinguishing between item-specific and relational information has proved to be a useful approach for understanding a variety of important memory phenomena, finding measurement tools for assessing the amount and type of information processed has proven difficult. Using the repeated-testing procedure, Burns (1993) demonstrated that item gains (the recall of items on a later test that were not recalled on earlier tests) and item losses (the forgetting of items on a later test that were recalled on earlier tests) reflected differences in amount of item-specific and relational information processed, respectively. Although several researchers have begun to use the measures with apparent success, the present research demonstrates that the accuracy of the item-gain measure is largely dependent on the rather arbitrary choice of recall-test length. We also show that a related but alternative measure, analysis of cumulative-recall curves, avoids some of the shortcomings of the item gain and loss measures. Moreover, we provide evidence for the generality of the cumulative-recall approach by demonstrating its effectiveness in mixed-list designs.  相似文献   
940.
We propose that we encode and store information as a function of the particular ways we have used similar information in the past. More specifically, we contend that the experience of retrieval can serve as a powerful cue to the most effective ways to encode similar information in comparable future learning episodes. To explore these ideas, we did two studies in which all participants went through study–test cycles of single category lists while we manipulated the nature of the recognition tests. The recognition tests either included only same-category lures or only different-category lures. The experience of repeated testing leads participants to avoid conceptual-based strategies but only when conceptual knowledge was poorly diagnostic for recognition (i.e., in the same-category lures condition). In a second study with a similar manipulation, we showed that repeated testing with lures from the same category as study items improved performance in a final recall surprise test compared to conditions in which different-category lures were used. Such a difference is akin to the one obtained when encoding instructions focus on distinctive item features compared to cases in which the focus is on relational processing. We suggest that testing requirements lead to adaptive changes at encoding.  相似文献   
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