首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Abilities and neural mechanisms underlying AB performance   总被引：3，自引：0，他引：3  
Schacter, Moscovitch, Tulving, McLachlan, and Freedman propose that infants may make the AB error because of immaturity of the memory system damaged in amnesia (e.g., the hippocampus). They contrast this with the proposal that infants may make the AB error because of immaturity of the frontal lobe system (Diamond; Diamond & Goldman-Rakic). Schacter et al.'s choice of subjects, however, did not permit a test of these 2 proposals, and characteristics of their task, such as length of delay, make comparison with infants difficult. Schacter et al. discuss sensitivity to proactive interference as a possible explanation for the AB error, but sensitivity to PI is more closely associated with frontal lobe damage than with amnesia. Schacter et al. associate perseveration with immaturity or damage to the frontal lobe; it is suggested here that this is better characterized as lack of inhibitory control. Tasks that are most likely to require frontal cortex function are those that demand both short-term memory and inhibitory control. AB is an excellent example of such a task.  相似文献   

2.
By constructing two suitable generalized Lyapunov functions, we derived a generalized ellipsoidal estimate of the globally attractive set and positively invariant set of the unified chaotic system with the parameters α=1/29 and 1/29〈α〈2/29, respectively, which extends some related results of Li, et al. [Li DM, Lu JA, Wu XQ, Chen GR, Estimating the global basin of attraction and positively invariant set for the Lorenz system and a unified chaotic system, Journal of Mathematical Analysis and Applications, 2006, 323（2）： 844-853]. The theoretical results obtained in this paper will find wide application in chaos control and synchronization.  相似文献   

3.
Studies on the conceptual system proposed by Harvey et aJ (1961) suggested that the concrete mode of cognitive functioning is associated with certain developmental factors such as restricted exploration of the environment, overcontrol by parents, avoidance of uncertainty, conformity to external superimposed norms, and discouragement of independence, etc. Using the framework of Harvey, Schroder et al (1967) specified two types of training methods, one of which he called the deductive method. Parents adopting this method provide the child with ready made and fixed rules. The child is taught to avoid uncertainty by looking externally for rules. The variety of perceptions and responses available to the child is highly restricted. The environment is so structured that it is unrealistically oversimplified. Schroder et al believe that this type of training method would bring out a cognitive structure which is characterized by compartmentalization and inability to think in terms of degrees or relativeness.  相似文献   

4.
Little, Bovaird and Widaman (2006) proposed an unconstrained approach with residual centering for estimating latent interaction effects as an alternative to the mean-centered approach proposed by Marsh, Wen, and Hau (2004, 2006). Little et al. also differed from Marsh et al. in the number of indicators used to infer the latent interaction factor and how they were represented, but this issue is separate from the mean versus residual centering distinction that was their primary focus. However, their implementation of the Marsh et al. mean-centered approach failed to incorporate the mean structure that Marsh et al. argued was necessary to obtain unbiased estimates. One might suppose that their new approach would suffer this same problem, an issue not addressed by Little et al. However, we demonstrate here why the Little et al. approach obviates this requirement that heretofore was thought to be necessary for all constrained, partially constrained, and unconstrained approaches. Both the Marsh et al. and Little et al. unconstrained approaches typically result in similar results and are much easier to implement than traditional constrained approaches. They differ primarily in that the Little et al. approach is a 2-step approach involving a potentially large number of separate analyses prior to estimating the structural equation model that apparently does not require the estimation of a mean structure, whereas the Marsh et al. approach is a 1-step approach that includes a mean structure.  相似文献   

5.
近年来,关于婴幼儿归纳推理能力的发展研究受到国际心理学界的重视,其中婴幼儿是否能够基于概念进行归纳推理是一个焦点问题。Mandler等人利用概括化模仿技术对婴儿的归纳推理进行了研究,发现:9-20个月的婴儿的归纳推理受到领域水平的概念类别所限制,是一个基于概念的过程;Gelman等人探讨了类别成员关系、语言标签、心理本质主义在幼儿的归纳推理中的作用,发现:2-4岁幼儿的归纳推理受基本水平的类别成员关系所限制,也是一个基于概念的过程。二者的分歧可以用语言的作用加以解释。  相似文献   

6.
Abstract

The main topic of this article is to consider the role of the State in providing higher education in Portugal, paying attention to the fact that the privatisation of higher education has been in place since the eighties (Amaral 1999) and also that it is difficult for students and their families to find the monetary resources needed for attendance at university (Cabrito 1999). The discussion focuses on the funding of higher education in a quasi‐market situation (Le Grand et al. 1993), as Portugal hasn't escaped the universal trend towards privatisation of education (Whitty et al. 1998). In the last decade, the relationship between State, universities and students has been changing rapidly (Acherman et al. 1989; Barr et al. 1993; Williams 1990; Henkel et al. 1999), and some arguments are presented that equity in access to higher education must be guaranteed (Mora 1997; UNESCO 1998; Williams 1992). In this connection, the need is argued for free attendance on higher education and State subsidies to students to cover the costs of education. Firstly, the economic and social condition of university students is presented. Using data from two periods, one academic year from the 60s and one from the 90s, the increase in the degree of equity that the university system had known in recent decades can be verified. According to the analysis, the Portuguese population in general is better represented in the university student body nowadays, than in the 60s. Therefore, it is possible to discuss the maintenance of a low degree of equity in the Portuguese university system. For this, the economic and social condition of university students is compared with ‐ that of the Portuguese population in the 90s. Secondly, the expectations of the students of higher education are presented, in order to understand the value attached by them to a university degree, which explains the social demand for education. Finally, the costs of higher education, both private and public, are evaluated. From this evaluation, it is possible to conclude that the principal source of funding of higher education costs is the student and his/her family and to discuss the need for a more interventionist State in higher education financing.  相似文献   

7.
The main topic of this article is to consider the role of the State in providing higher education in Portugal, paying attention to the fact that the privatisation of higher education has been in place since the eighties (Amaral 1999) and also that it is difficult for students and their families to find the monetary resources needed for attendance at university (Cabrito 1999). The discussion focuses on the funding of higher education in a quasi-market situation (Le Grand et al. 1993), as Portugal hasn't escaped the universal trend towards privatisation of education (Whitty et al. 1998). In the last decade, the relationship between State, universities and students has been changing rapidly (Acherman et al. 1989; Barr et al. 1993; Williams 1990; Henkel et al. 1999), and some arguments are presented that equity in access to higher education must be guaranteed (Mora 1997; UNESCO 1998; Williams 1992). In this connection, the need is argued for free attendance on higher education and State subsidies to students to cover the costs of education. Firstly, the economic and social condition of university students is presented. Using data from two periods, one academic year from the 60s and one from the 90s, the increase in the degree of equity that the university system had known in recent decades can be verified. According to the analysis, the Portuguese population in general is better represented in the university student body nowadays, than in the 60s. Therefore, it is possible to discuss the maintenance of a low degree of equity in the Portuguese university system. For this, the economic and social condition of university students is compared with – that of the Portuguese population in the 90s. Secondly, the expectations of the students of higher education are presented, in order to understand the value attached by them to a university degree, which explains the social demand for education. Finally, the costs of higher education, both private and public, are evaluated. From this evaluation, it is possible to conclude that the principal source of funding of higher education costs is the student and his/her family and to discuss the need for a more interventionist State in higher education financing. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

8.
A generalized Lyapunov function was employed to investigate the ultimate bound and positively invariant set of a generalized Lorenz system. We derived an ellipsoidal estimate of the ultimate bound and positively invariant set for the generalized Lorenz system, for all the positive values of system parameters a, b, and c. Our results extend the related result of Li, et al. [Li DM, Lu JA, Wu XQ, et al., Estimating the ultimate bound and positively invariant set for the Lorenz system and a unified chaotic system, Journal of Mathematical Analysis and Application, 2006, 323（2）： 844-653].  相似文献   

9.
Research suggests potential problems when group work is used in school science to support the integrated acquisition of conceptual understanding and testing procedures. Yet integrated acquisition is promoted by current policy, and is a popular classroom strategy. Work by Howe et al. (Learning and Instruction 10 (2000) 361) indicates that the problems may be overcome if pupils: (a) discuss conceptual material in small groups and reach consensus; (b) subject consensual positions to guided empirical appraisal. The present paper reports a study with 9–12-year old pupils, which tests the proposal of Howe et al. using heat transfer as its topic, in contrast to the shadow size of Howe et al. In broad terms, the results are consistent with what Howe et al. report, although there are subtle differences in both outcome and process. Nevertheless, the similarities are such as to indicate a robust technique, with clear relevance to classroom practice. To facilitate application, the paper outlines what the technique requires in terms of group organisation and teacher support, and suggests that in both cases there is consistency with current practice.  相似文献   

10.
At the First International Conference on Teaching Statistics (Grey et al. 1983), several papers dealth with simulation games, either with or without a computer to assist in the teaching of a variety of statistical concepts (Mead 1983, Elliott 1983, Bright et al. 1983a, b, Joiner 1983, Singh 1983). One area not covered was survey sampling which is the subject of this article.  相似文献   

11.
Reviews     
Bourner, Tom et al ed (2000) New Directions in Professional Higher Education
Cannon, Robert & Newble, David (2000) Handbook for Teachers in Universities and Colleges
Evans, Terry & Nation, Darryl eds (2000) Changing University Teaching
French, Deanie et al eds (1999) Internet Based Learning
Hunter, Dale et al (1999) Handling Groups in Action
Maier, Pat & Warren, Adam (2000) Integr@ting Technology in Learning and Teaching
Ryan, Steve et al (2000) The Virtual University
Also received
Brown, Sally et al (2000) 500 Tips on Assessment
Entz, Susan & Galarza, Sheri Lyn (2000) Picture This:
Feldman, Alan et al (2000) Network Science, a Decade Later
Jukes, Ian et al (2000) net.savvy
Scott, Elspeth (2000) Managing the Internet in the Primary and Secondary School Library  相似文献   

12.
Previous investigations of the productivity of educational psychologists (Smith et al., 1998, Smith et al., 2003) have used a points system that defines high productivity as having few co-authors and high authorship placement. Due to the increasingly collaborative nature of educational psychology research (Robinson, McKay, Katayama, & Fan, 1998), defining productivity in this way may not fully capture the essence of our work nor provide the most useful information for potential graduate students. In taking a closer look at the most-published persons in educational psychology journals from 1991 to 2002, we found that most also published even more articles in other journals and regularly included co-authors, especially graduate students. Some persons, who have not been recognized as being the most productive in the Smith et al. lists, published considerably more articles than others who have appeared in those lists.  相似文献   

13.
DVB-S2 inner receiver design for broadcasting mode   总被引：1，自引：0，他引：1  
INTRODUCTION The second generation satellite digital video broadcasting standard (ETSI, 2004) has come out recently. Compared with the previous satellite stan-dard DVB-S (ETSI, 2003), DVB-S2 has more ad-vantages, such as the 30% increase in channel capac-ity, the more reliable performance, and the more ef-ficient usage of transponders. The DVB-S2 standard has been designed having in mind the peculiarities of the satellite channel, particularly the link fading im-pairments and the …  相似文献   

14.
《Learning and Instruction》2003,13(4):349-365
In this study, we show that the benefits of phonological training upon reading skills, aptly demonstrated by Lundberg, Frost, and Petersen (Reading Res. Q., 23 (1988) 263), can be obtained even in less favourable conditions featuring a smaller dose of training in a kindergarten culture impregnated by knowledge of phonological awareness and reading. As a consequence, the control group in the present study demonstrated vastly better pre-school reading skills than the one in Lundberg et al. (1988). One experimental group received a training dose of only 60% of that administered by Lundberg et al. (1988). The results replicated those of Lundberg et al. (1988) even for the group with a 60% training dose. A significant gain in word reading was maintained until the end of grade 2 both for mainstream pupils and children-at-risk. A spelling gain was observed only for children-at-risk in grade 2.It is suggested that training must be strictly systematic in order to be effective. The results are discussed in terms of metacognitive insights into reading that are gained through training in phonological awareness.  相似文献   

15.
高校实验室仪器设备管理方法探讨   总被引：1，自引：0，他引：1  
目前高校实验室仪器设备管理中存在重购置轻管理、重使用轻维护、仪器设备存在部分闲置,设备资产配置不均衡等问题。针对这些问题,提出了相应的解决方案。即通过加强仪器设备管理制度的完善,探索科学高效的管理方法、加大维护维修方面的经费投入,建立完善的维护维修制度、合理调配资源,提升仪器使用价值等几个方面来加强实验室管理的标准化。  相似文献   

16.
以风险管理理论与方法为基础,采用文献资料调研、专家访谈、问卷调查、现场调查、逻辑分析、数理统计等方法,结合福建省游泳场馆救生员现状,研究救生员风险及游泳场馆溺死问题,旨在建立游泳场馆安全管理体系。结果表明,游泳场馆救生员风险源包括13个风险因素,福建省游泳场馆救生员面临7个主要风险因素,游泳场馆可以采用风险避免、风险控制、风险转移和风险自留四种方法应对救生员风险。  相似文献   

17.
利用作者最近导出的解析的ｂｃｃ结构的嵌入原子模型计算了由Ｖ、Ｎｂ、Ｔａ、Ｃｒ、Ｍｏ、Ｗ和Ｆｅ等７个ｂｃｃ结构元素组成的２１个合金系统的中间化合物Ａ＿３Ｂ、ＡＢ、ＡＢ＿３结构的形成焓，计算得到的形成焓跟Ｗａｔｓｏｎ等人用经验能带理论得到的结果、Ｃｏｌｉｎｅｔ等人用集团方法得到的结果、Ｍｉｅｄｅｍａ等人用经验热力学理论（Ｍｉｅｄｅｍａ理论）得到的结果、以及已有的实验结果符合得比较好．  相似文献   

18.
基因组重排问题是分子生物学中的重要问题,进化问题的研究可归结为进化距离问题的研究.即计算从一个基因组进化为另一个基因组所需的最少的进化变换数目.可借助基因组之间的圈图研究翻转进化问题,Hannenhalli给出了一个计算圈图分支的一个线性时间算法,但考察的对象为圈图上的圈集合,且需要一些等价变换.从边集合出发给出了计算有向基因组的圈图连通分支的线性时间算法.  相似文献   

19.
狭义相对论是20世纪最伟大的物理学理论之一。一直以来,狭义相对论的公理化问题受到物理学家和逻辑学家的共同关注。但由于学科的交叉性,这个问题一直没有得出很好的结论。匈牙利学者HajnalAndréka等人于2007年提出了一个狭义相对论的一阶逻辑系统Specrel,我们发现这个系统无论在逻辑上,还是在物理上要刻画狭义相对论都是不够的。我们在此基础上提出了狭义相对论的另一个一阶逻辑系统Specrel’,并在这个系统中证明了洛仑兹变换——这一狭义相对论的重要基础公式。从而可以得到"动钟变慢"、"动尺收缩"等一系列狭义相对论的典范效应。  相似文献   

20.
Developing scientific literacy about water systems is critical for K-12 students. However, even with opportunities to build knowledge about the hydrosphere in elementary classrooms, early learners may struggle to understand the water cycle (Forbes et al., 2015 ; Gunckel et al., 2012 ; Zangori et al., 2015 ; Zangori et al., 2017 ). Scientific modeling affords opportunities for students to develop representations, make their ideas visible, and generate model-based explanations for complex natural systems like the water cycle. This study describes a comprehensive evaluation of a 5-year, design-based research project focused on the development, implementation, revision, and testing of an enhanced, model-centered version of the Full Option Science System (FOSS) Water (2005) unit in third grade classrooms. Here, we build upon our previous work (Forbes et al., 2015 a; b; Vo et al., 2015 ; Zangori et al., 2015 ; Zangori et al., 2017 ) by conducting a comparative analysis of student outcomes in two sets of classrooms: (1) one implementing the modeling-enhanced version of the FOSS Water unit developed by the research team (n = 6), and 2) another using the standard, unmodified version of the same curricular unit (n = 5). Results demonstrate that teachers in both conditions implemented the two versions of the curriculum with relative fidelity. On average, students exposed to the modeling-enhanced version of the curriculum showed greater gains in their model-based explanations for the hydrosphere. Engagement in scientific modeling allowed students to articulate hydrologic phenomena by (1) identifying various elements that constitute the hydrosphere, (2) describing how these elements influenced the movement of water in the hydrosphere, and (3) demonstrating underlying processes that govern the movement of water in the hydrosphere.  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