凸度量空间中相容映象的不动点及非线性映象的迭代序列的收敛性

本文讨论凸度量空间中相容映象的不动点的存在性以及非线性映象的迭代序列的收敛性。所得结果推广和发展了参考文献[3]～[17]中的一些主要结果。     

Images in mirrors: Recollections,alternative explanations and modes of cognitive functioning

Students' conceptions of how objects are seen directly, and in mirrors, were explored in an analysis of their written and drawn responses to common visual phenomena depicted in cartoons with brief text. Students in Grades K-10 (n=214) completed a questionnaire and some were interviewed. Evidence was sought to support an hypothesis for increasingly sophisticated responses related to the concepts of sight, light, reflection and image. The developmental model used in this analysis was the updated SOLO Taxonomy (Biggs & Collis, 1991; Collis & Biggs 1991). It appears from the results that different modes of functioning can interfere to produce factually incorrect recollections of experience particularly in the age group 7 to 13 years approximately. Also, this is associated with the common spurious conception that mirrors have a lateral inversion property. Explanations involving light were extremely rare and its role related to the production of an image ‘in the mirror’ but not to the perception of an image in the eyes. Specializations: science education, students' understandings of phenomena in science. Specializations: cognitive development, evaluation, mathematics and science education. Specializations: mathematics education, students' understanding of chance and data concepts.     

公开选拔党政领导干部考试制度的现实分析与瞻前探讨

作为强化国家治理效能的一项治本决策,公开选拔党政领导干部考试制度的创建与推行,实现了历史性的超越,并有其独具的时代价值。但相对国际形势、国内改革和建设新变化、新发展对领导干部考选提出的新需求而言,现行公选考试的科学化、规范化、制度化建设,仍滞后于时代发展的进程。把牢政治方向,正确处理三种关系;建立健全三项制度;完善优化组织和规则体系;加强三种理论的应用和实证研究;加速四库建设,更新技术手段等,是公选考试制度进一步健全完善的必需。     

A Transactional Approach to Transfer Episodes

In this article we present an analytical framework for approaching transfer episodes—episodes in which participants declare or can be declared to bring prior experience to bear on the current task organization. We build on Dewey’s writings about the continuity of experience, Vygotsky’s ideas of unit analysis, as well as more recent developments in continental philosophy to develop a transactional approach that involves reconceptualizing the notion of experience. In this view, experience is not something that individuals have but an analytical category that denotes the unity of whole persons, their material and social environment, and their changing transactional relations (mutual effects on each other) across time. In the 1st part of the article, we present the theory and contrast it with past and present literature on transfer. In the 2nd part, we develop the methodological implications and analyze an episode of transfer from a technology-enhanced science education curriculum in which students were presented with analogous models of scientific phenomena across different tasks. We describe instances of recognition, of analogical reasoning, and of how students applied theoretical knowledge in terms of transactional units of change. We conclude by discussing implications with regard to further theoretical development and educational practice.     

Professional development and perceived needs of science teachers

About 100 science teachers in the Sydney Metropolitan West Region were surveyed to determine their professional development needs and the ways in which these needs could be met. The findings provide a ranking of science teacher perceived professional development needs, a list of possible incentives to motivate science teachers to complete inservice programs (in priority order) and an indication of the preferred modes of presentation to meet professional development needs. In general, science teachers stated a preference for professional development related to modern trends in science education directly related to classroom practice. In contrast to recommendations from DEET, science teachers indicated a preference for traditional models of inservice. Data related to preferred mode of inservice indicated significant gender differences. Specializations: science teacher professional development. Specializations: educational psychology and research design. Specialization: constructivist approaches in science education.     

Teachers’ Role in Students’ Learning at a Project-Based STEM High School: Implications for Teacher Education

International Journal of Science and Mathematics Education - This study explored how teachers engage and support students at a project-based STEM high school to identify key elements defining...     

Twelfth-grade biology pupils' opinions on interventions of man in nature: Agreement,indifference and ambivalence

The purpose of this study was to assess the degree of ambivalence of the attitudes of twelfth-grade biology pupils in Israel towards interventions of man in nature. A questionnaire was designed in which the pupils were confronted with arguments of different levels of potential relevance (personal, global, and philosophical), three against and three in favor of each of eight “interventions of man in natural processes.” The pupil was requested (a) to rate each argument independently and (b) to “vote,” as if in a public committee, for or against each technology. The degree of ambivalence–-measured, for each item, by means of Kaplan's (1972) semantic differential half scales–-was the degree to which the pupils agreed to both positive and negative arguments. Although clear majorities of pupils voted in favor of all the “interventions,” three main patterns of responses were found: general agreement, indifference, and ambivalence. These patterns were characterized in terms of (a) the mean ratings of the arguments, (b) the differences between mean positive and negative “personal” ratings, (c) the percentages of favorable votes, and (d) the degrees of ambivalence. It was shown that pupils were able to appreciate arguments against a certain technology even in cases of strong personal feelings in favor of the technology (high ambivalence). The development of such an ability may be one of the main objectives of science education in a STS context.     

Factors in the development of proportional reasoning strategies by concrete operational college students

This study was designed as a test for two neo-Piagetian theories. More specifically, this research examined the relationships between the development of proportional reasoning strategies and three cognitive variables from Pascual-Leone's and Case's neo-Piagetian theories. A priori hypotheses linked the number of problems students worked until they induced a proportional reasoning strategy to the variables of M-space, degree of field dependence, and short-term storage space. The subjects consisted of students enrolled in Physical Science I, a science course for nonscience majors at the University of Southern Mississippi. Of the 34 subjects in the study, 23 were classified as concrete operational on the basis of eight ratio tasks. Problems corresponding to five developmental levels of proportional reasoning (according to Piagetian and neo-Piagetian theory), were presented by a microcomputer to the 23 subjects who had been classified as concrete operational. After a maximum of 6 hours of treatment, 17 of the 23 subjects had induced ratio schemata at the upper formal level (IIIB), while the remaining subjects used lower formal level (IIIA) schemata. The data analyses showed that neither M-space and degree of field-dependence, either alone or in combination, nor short-term storage predicted the number of problems students need to do until they induce an appropriate problem-solving strategy. However, there were significant differences in the short-term storage space of those subjects who mastered ratio problems at the highest level and those who did not. Also, the subjects' degree of field-dependence was not a predictor of either the ability to transfer problem-solving strategies to a new setting or the reuse of inappropriate strategies. The results of this study also suggest that short-term storage space is a variable with high correlations to a number of aspects of learning such as transfer and choice of strategy after feedback.     

Physics students' epistemologies and views about knowing and learning

Classrooms are complex environments in which curriculum, students, and teachers interact. In recent years a number of studies have investigated the effect of teachers' epistemologies on the classroom environment, yet little is known about students' epistemologies and how these interact with those of teachers. The purpose of this study was to document students' epistemologies and their concurrent views about knowing and learning. Using a written essay, short-answer responses to statements, a preferred classroom environment inventory, and interviews, students' views on scientific knowledge and their own knowing and learning were collected from 42 students in three sections of an introductory physics course. Our rather broad, qualitative inquiry provides a dynamic view of students' understanding of knowing and learning in high school physics. Our analyses reveal a spectrum of epistemological commitments commensurable with positions from objectivism to relativism, most of them with experientialist coloring. Even within individuals, these commitments could be at once commensurable and incommensurable with the same epistemological position. We also find rather significant inter- and intra-individual differences with respect to the consequences of a specific epistemological stance to learning, the learning strategies employed, and the learning environment preferred. Students' views on knowing and learning in physics are presented in the form of an emergent theory. The findings are discussed in terms of their application to classroom environments.