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401.
Ji-Eun Lee 《The Journal of Mathematical Behavior》2007,26(1):48-59
This classroom scholarship report presents a group of elementary students’ experiences learning the traditional long division algorithm. The traditional long division algorithm is often taught mechanically, resulting in the student's performance of step-by-step procedures with no or weak understanding of the concept. While noting some initial difficulties, the class episodes in this article provide examples of internalization that highlight the active role of the learner in transforming concrete representations into an abstract algorithm. Several factors encouraged students to be deeply engaged in making sense of the long division algorithm: meaningful tasks based on a theoretically well-articulated curriculum, effective pedagogical measures, and dynamic class discussions. 相似文献
402.
“Lesson plan study” (LPS), adapted from the Japanese Lesson Study method of professional development, is a sequence of activities designed to engage prospective teachers in broadening and deepening their understanding of school mathematics and teaching strategies. LPS occurs over 5 weeks on the same lesson topic and includes four opportunities to revisit one's own ideas and the ideas of others. In this paper, we describe one prospective teacher's growth in understanding right triangle trigonometry as she participated in LPS. This study is part of a much larger study investigating how prospective secondary teachers learn to teach mathematics within the context of LPS. Results of this study indicate that Image Saying, an activity for growth in understanding from the Pirie-Kieren model [Pirie, S., & Kieren, T. (1994). Growth in mathematical understanding: How can we characterize it and how can we represent it? Educational Studies in Mathematics, 26, 165-190], is critical to prospective teachers’ growth in understanding school mathematics. Multiple opportunities and contexts within which to share understanding of school mathematics led to significant growth in understanding of right triangle trigonometry which in turn led to growth in understanding of teaching strategies. That is, the results of this study indicate that growth in understanding school mathematics (what to teach) leads to growth in understanding teaching strategies (how to teach) as prospective teachers participate in LPS. 相似文献
403.
Arsalan Wares 《International Journal of Mathematical Education in Science & Technology》2017,48(6):938-941
The purpose of this short paper is to describe a new proof of the Pythagorean Theorem that involves paper folding. 相似文献
404.
Behiye Ubuz Yurdagül Aydınyer 《International Journal of Mathematical Education in Science & Technology》2017,48(7):1072-1086
The current study aimed to construct a questionnaire that measures students’ personality traits related to striving for understanding and learning value of geometry and then examine its psychometric properties. Through the use of multiple methods on two independent samples of 402 and 521 middle school students, two studies were performed to address this issue to provide support for its validity. In Study 1, exploratory factor analysis indicated the two-factor model. In Study 2, confirmatory factor analysis indicated the better fit of two-factor model compared to one or three-factor model. Convergent and discriminant validity evidence provided insight into the distinctiveness of the two factors. Subgroup validity evidence revealed gender differences for striving for understanding geometry trait favouring girls and grade level differences for learning value of geometry trait favouring the sixth- and seventh-grade students. Predictive validity evidence demonstrated that the striving for understanding geometry trait but not learning value of geometry trait was significantly correlated with prior mathematics achievement. In both studies, each factor and the entire questionnaire showed satisfactory reliability. In conclusion, the questionnaire was psychometrically sound. 相似文献
405.
This paper adds to the growing body of research happening in multivariable calculus by examining scalar and vector line integrals. This paper contributes in two ways. First, this paper provides a conceptual analysis for both types of line integrals in terms of how theoretical ways of thinking about definite integrals summarized from the research literature might be applied to understanding line integrals specifically. Second, this paper provides an initial investigation of students’ understandings of line integral expressions, and connects these understanding to the theoretical ways of thinking drawn from the literature. One key finding from the empirical part is that several students appeared to understand individual pieces of the integral expression based on one way of thinking, such as adding up pieces or anti-derivatives, while trying to understand the overall integral expression through a different way of thinking, such as area under a curve. 相似文献
406.
Ratchada Viriyapong Monthicha Sookpiam 《Mathematical Methods in the Applied Sciences》2019,42(18):6906-6916
Online game addiction has become a large problem worldwide, and it could give negative impacts on children in many ways such as physical health, learning, emotion, and behavior. Online game addiction is mostly found in children and youth at the age of 15 to 24 years. Therefore, in this paper, we have developed a mathematical model of online game addiction to explore the effects of education campaign and family understanding on online game addiction in Thailand. Analysis of this model reveals two main equilibria, addiction‐free (AFE) and addiction‐present (APE) ones. Results show that the AFE is locally asymptotically stable when the value of basic reproduction number (R0) is less than the unity; otherwise, there is a unique endemic equilibrium point, and it is locally stable when satisfies the Routh‐Hurwitz criterion. Further, the conditions of AFE to be globally stable are demonstrated. Finally, the results of sensitivity analysis and numerical simulation show that the effectiveness of both education campaign and family understanding is an important factor in reducing the value of R0 and holds great promise for lowering the number of children and youth who addict to online game in Thailand. 相似文献
407.
Roald Hoffmann Jean-Paul Malrieu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12690-12710
We begin our tripartite Essay with a triangle of understanding, theory and simulation. Sketching the intimate tie between explanation and teaching, we also point to the emotional impact of understanding. As we trace the development of theory in chemistry, Dirac's characterization of what is known and what is needed for theoretical chemistry comes up, as does the role of prediction, and Thom's phrase “To predict is not to explain.” We give a typology of models, and then describe, no doubt inadequately, machine learning and neural networks. In the second part, we leave philosophy, beginning by describing Roald's being beaten by simulation. This leads us to artificial intelligence (AI), Searle's Chinese room, and Strevens’ account of what a go-playing program knows. Back to our terrain—we ask “Quantum Chemistry, † ca. 2020?” Then move to examples of AI affecting social matters, ranging from trivial to scary. We argue that moral decisions are hardly to be left to a computer. At this point, we try to pull the reader up, giving the opposing view of an optimistic, limitless future a voice. But we don't do justice to that view—how could we? We return to questioning the ascetic dimension of scientists, their romance with black boxes. Onward: In the 3rd part of this Essay, we work our way up from pessimism. We trace (another triangle!) the special interests of experimentalists, who want the theory we love, and reliable numbers as well. We detail in our own science instances where theory gave us real joy. Two more examples-on magnetic coupling in inorganic diradicals, and the way to think about alkali metal halides, show us the way to integrate simulation with theory. Back and forth is how it should be—between painfully-obtained, intriguing numbers, begging for interpretation, in turn requiring new concepts, new models, new theoretically grounded tools of computation. Through such iterations understanding is formed. As our tripartite Essay ends, we outline a future of consilience, with a role both for fact-seekers, and searchers for understanding. Chemistry's streak of creation provides in that conjoined future a passage to art and to perceiving, as we argue we must, the sacred in science. 相似文献
408.
刘文 《科技情报开发与经济》2011,21(9):115-118
介绍了默契信息交流的特点,阐述了默契信息交流与一般信息交流的区别,对默契信息交流的障碍进行了分析,并提出了克服默契信息交流障碍的几点建议。 相似文献
409.
十六大以来,党中央对文化建设高度重视,经过长期的实践探索和理论创新,初步找到了一条中国特色的文化发展道路。这条道路的重要标志就是在科学发展观的指引下形成了新的文化发展理念,初步掌握了社会主义初级阶段文化发展的客观规律。新的文化发展理念深化了对文化的地位和作用、文化发展方向、发展状态、发展原则、发展思路、发展动力、发展格局、发展目标等的认识,取得了较为系统的创造性理论成果。民族性传统、开放性品格、安全性战略、人本性宗旨、严密性逻辑,是该理论成果的主要特征。 相似文献
410.
提出了同步边缘特性检测的轮廓跟踪算法，并基于规则从扫描图像全图轮廓中分离字符轮廓；在此基础上，针对机械工程图，采用全方位的邻域搜索技术生成不同方向的字符串，通过分类树进行识别，并根据专业领域知识进行校正．实验测试表明，该方法具有较好的效果 相似文献