• Journal of Educational Research in Mathematics
• /
• v.8 no.2
• /
• pp.553-563
• /
• 1998

In this thesis, I examined Bruner's EIS theory from the viewpoint of epistemology based on Piaget's genetic epistemology. Although Bruner's ideal thought which insisted ‘to teach the structure’accepted Piaget's theory in the methodology of realization, it is different from Piaget in understanding knowledge. The difference is shown from understanding the meaning of ‘structure’. Piaget's concept of structure is something that has overcome the realistic viewpoint of the traditional epistemology and is reconstructed through endless self-regulative transformational process. However Bruner's is used as a realistic meaning as we can see in the Plato's recollection theory. Therefore Piaget's ‘stage of development’means the difference of structure which lies in the generative process and it includes the qualitive difference of level. On the other hand, Bruner, who is trying to translate and suggest the fixed structure to the children understood Piaget's stage of development as the difference in the ways of representation. Piaget's operational constructivism insists that the children should ‘construct’the knowledge through their activity, and especially in case of the lohico-mathematical recognition, the source should be internalized activity, that is, operation. In view of this assertion, Burner's idea which insists to accept the structure of knowledge as a fixed reality and to suggest the translated representation proper to the cognitive structure of the children to teach them, has a danger of emphasizing only the functional aspects to deliver the given knowledge ‘quickly’. And it also has the danger of damaging ‘the nature of the knowledge’in the translated knowledge.

• Education of Primary School Mathematics
• /
• v.18 no.3
• /
• pp.175-190
• /
• 2015

This study investigated the effect of team project activity for game making on the elementary mathematically gifted students' community care and organizational management capacity. 7 mathematically gifted students of 4th grade are selected and participated. After 15 hours activities during 2 months of team project on game making, their community care and organizational management capacity were improved. This results suggested that leadership education is possible in mathematics curriculum for mathematics gifted students.

• Korean Journal of Childcare and Education
• /
• v.15 no.3
• /
• pp.39-60
• /
• 2019

Objective: The purpose of this study was to analyze the Nuri-curriculum daycare programs for 3, 4, and 5-year-olds based on the Child Welfare Act. Methods: Data were analyzed according to the analysis criteria for 195 children's safety education programs in the Nuri-Program. The analyzed data used frequency and percentages. Results: First, life safety education was the most important element. And after looking at the contents category of the Child Welfare Act, the results in order are as follows: "raffic safety"; "Health and hygiene management, including the prevention of contagious diseases and drug abuse"; "Safety measures against disasters"; "Precaution and prevention of disappearance and abduction"; and "Prevention of sexual violence and child abuse." Second, there were many safety education activities in accordance to chronological age (3-to 5-years old). Health and safety by subject, season, and life tools were more frequent. By type of activity, conversation and language activity, fairy tales, and plays were the most common activities. Conclusion/Implications: This suggests the need to systematically plan safety education content through a program that links safety-related laws and elements related to the Nuri curriculum in child care centers.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.20 no.6
• /
• pp.73-82
• /
• 2012

The main and side reactions of the three selective catalytic reduction (SCR) reactions with ammonia over a vanadium-based catalyst have been investigated using synthetic gas mixtures in the temperature range of $170{\sim}590^{\circ}C$. The three SCR reactions are standard SCR with pure NO, fast SCR with an equimolar mixture of NO and $NO_2$, and $NO_2$ SCR with pure $NO_2$. Vanadium based catalyst has no significant activity in NO oxidation to $NO_2$, while it has high activity for $NO_2$ decomposition at high temperatures. The selective catalytic oxidation of ammonia and the formation of nitrous oxide compete with the SCR reactions at the high temperatures. Water strongly inhibits the selective catalytic oxidation of ammonia and the formation of nitrous oxide, thus increasing the selectivity of the SCR reactions. However, the presence of water inhibits the SCR activity, most pronounced at low temperatures. In this study, the experimental results are analyzed by means of a dynamic one-dimensional isothermal heterogeneous plug-flow reactor (PFR) model according to the Eley-Rideal mechanism.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.05
• /
• pp.165-170
• /
• 1997

In this paper, we consider the aortic sinus baroreceptor, which is the most representative baroreceptors sensing the variance of pressure in the cardiovascular system(CVS), and propose heart activity control model to observe the effect of delay time in heart period and stroke volume under the regulation of baroreflex in arotic sinus. The proposed heart activity baroreflex regulation model contains CVS electric circuit sub-model, baroreflex regulation sub-model and time delay sub-model. In these models, applied electric circuit sub-model is researched by B.C.Choi and the baroreflex regulation sub-model transforms the input, the arotic pressure of CVS electric circuit sub-model, to outputs, heart period and stroke volume by mathematical nonlinear feedback. We constituted the time delay sub-model to observe sensitivity of heart activity baroreflex regulation model by using the variable value to represent the control signal transmission time from the output of baroreflex regulation model to efferent nerve through central nervous system. The simulation object of this model is to observe variability of the CVS by variable value in time delay sub-model. As simulation results, we observe three patterns of CVS variability by the time delay. First, if the time delay is over 2.5 sec, arotic pressure, stroke volume and heart rate is observed nonperiodically and irregularly. Second, if the time delay is from between 0.1 sec and 0.25 sec, the regular oscillation is observed. Finally, if time delay is under 0.1 sec, then heart rate and arotic pressure-heart rate trajectory is maintained in stable state.

• Journal of the Korean School Mathematics Society
• /
• v.22 no.3
• /
• pp.257-275
• /
• 2019

Technology-based convergence education is being emphasized for students in the era of the fourth industrial revolution. In math education, students need to increase their capabilities in the future by having them experience mathematical problems using robots and sensors, a key technology in the era of the fourth industrial revolution. To this end, it is necessary to present educational uses for educational robots in relation to math and curriculum from a 'mathematics education perspective' and analyze its educational use in relation to the mathematics and curriculum, considering the role of mathematics at the base of the process of exploring real-world phenomena and solving problems. Based on the analysis of Van Hiele levels of development in geometry and the LOGO activity level of Olson et al.(1987), this study analyzed and presented the level of LEGO Mindstorm activity, a representative educational Robot capable of collecting and analyzing data and programming in the form of block language, in the first to fourth level.

• Education of Primary School Mathematics
• /
• v.2 no.1
• /
• pp.3-13
• /
• 1998

In mathematics education we have focused on how to improve the problem-solving ability, which makes its way to the new direction with the introduction of meta-cognition. As meta-cognition is based on cognitive activity of learners and concerned about internal properties, we may find a more effective way to generate learners problem-solving power. Its means that learners can regulate cognitive process according to their gorls of learning by themselves. Moreover, they are expected to make active participation through this process. If specific meta problems designed to develop meta-cognition are offered, learners are able to work alone by means of their own cognition and regulation while solving problems. They can transfer meta-cognition to the other subjects as well as mathematics. The studies on meta-cognition conducted so far may be divided into these three types. First in Flavell(［3］) meta-cognition is defined as the matter of being conscious of one's own cognition, that is, recognizing cognition. He conducted an experiment with presschoolers and children who just entered primary school and concluded that their cognition may be described as general stage that can not link to specific situation in line with Piaget. Second, Brown(［1］, ［2］) and others argued that meta-cognition means control and regulation of one's own cognition and tried to apply such concept to classrooms. He tried to fined out the strategies used by intelligent students and teach such types of activity to other students. Third, Merleary-Ponty (1962) claimed that meta-cognition is children's way of understanding phenomena or objects. They worked on what would come out in children's cognition responding to their surrounding world. In this paper following the model of meta-cognition produced by Lester (［7］) based on such ideas, we develop types of meta-cognition. In the process of meta-cognition, the meta-cognition working for it is to be intentionally developed and to help unskilled students conduct meta-cognition. When meta-cognition is disciplined through meta problems, their problem-solving power will provide more refined methods for the given problems through autonomous meta-cognitive activity without any further meta problems.

• Communications of Mathematical Education
• /
• v.25 no.2
• /
• pp.473-495
• /
• 2011

Across the secondary school, students deal with the algebraic conditions like as identity, inverse, commutative law, associative law and distributive law. The algebraic structures, group, ring and field, are determined by these algebraic conditions. But the conditioning of these algebraic structures are not mentioned at all, as well as the meaning of the algebraic structures. Thus, students is likely to be considered the algebraic conditions as productions from the number sets. In this study, we systematize didactically the meanings of algebraic conditions and algebraic structures, considering connections between the number systems and the solutions of the equation. Didactically systematizing is to construct the model for student's natural mental activity, that is, to construct the stream of experience through which students are considered mathematical concepts as productions from necessities and high probability. For this purpose, we develop the program for the gifted, which its objective is to teach the meanings of the number system and to grasp the algebraic structure conceptually that is guaranteed to solve equations. And we verify the effectiveness of this developed program using didactical experiment. Moreover, the program can be used in ordinary students by replacement the term 'algebraic structure' with the term such as identity, inverse, commutative law, associative law and distributive law, to teach their meaning.

• Journal of Educational Research in Mathematics
• /
• v.15 no.3
• /
• pp.251-272
• /
• 2005

Given that cognitive demands of mathematical tasks can be changed during instruction, this study attempts to provide a detailed description to explore how tasks are set up and implemented in the classroom and what are the classroom-based factors. As an exploratory and qualitative case study, 4 of six-grade classrooms where high-level tasks on ratio and proportion were used were videotaped and analyzed with regard to the patterns emerged during the task setup and implementation. With regard to 16 tasks, four kinds of Patterns emerged: (a) maintenance of high-level cognitive demands (7 tasks), (b) decline into the procedure without connection to the meaning (1 task), (c) decline into unsystematic exploration (2 tasks), and (d) decline into not-sufficient exploration (6 tasks), which means that the only partial meaning of a given task is addressed. The 4th pattern is particularly significant, mainly because previous studies have not identified. Contributing factors to this pattern include private-learning without reasonable explanation, well-performed model presented at the beginning of a lesson, and mathematical concepts which are not clear in the textbook. On the one hand, factors associated with the maintenance of high-level cognitive demands include Improvising a task based on students' for knowledge, scaffolding of students' thinking, encouraging students to justify and explain their reasoning, using group-activity appropriately, and rethinking the solution processes. On the other hand, factors associated with the decline of high-level cognitive demands include too much or too little time, inappropriateness of a task for given students, little interest in high-level thinking process, and emphasis on the correct answer in place of its meaning. These factors may urge teachers to be sensitive of what should be focused during their teaching practices to keep the high-level cognitive demands. To emphasize, cognitive demands are fixed neither by the task nor by the teacher. So, we need to study them in the process of teaching and learning.

• Education of Primary School Mathematics
• /
• v.20 no.4
• /
• pp.253-266
• /
• 2017

The purpose of the study was to investigate the perceptions of Elementary school teachers on mathematics instruction. To do this, 7 test items were developed to obtain data on teacher's perception of mathematics instruction and 73 teachers who take mathematical lesson analysis lectures were selected and conducted a survey. Since the data obtained are all qualitative data, they were analyzed through coding and similar responses were grouped into the same category. As a result of the survey, several facts were found as follow; First, When teachers thought about 'mathematics', the first words that come to mind were 'calculation', 'difficult', and 'logic'. It is necessary for the teacher to have positive thoughts on mathematics and mathematics learning, and this needs to be stressed enough in teacher education and teacher retraining. Second, the reason why mathematics is an important subject is 'because it is related to the real life', followed by 'because it gives rise to logical thinking ability' and 'because it gives rise to mathematical thinking ability'. These ideas are related to the cultivating mind value and the practical value of mathematics. In order for students to understand the various values of mathematics, teachers must understand the various values of mathematics. Third, the responses for reasons why elementary school students hate mathematics and are hard are because teachers demand 'thinking', 'because they repeat simple calculations', 'children hate complicated things', 'bother', 'Because mathematics itself is difficult', 'the level of curriculum and textbooks is high', and 'the amount of time and activity is too much'. These problems are likely to be improved by the implementation of revised 2015 national curriculum that emphasize core competence and process-based evaluation including mathematical processes. Fourth, the most common reason for failing elementary school mathematics instruction was 'because the process was difficult' and 'because of the results-based evaluation'. In addition, 'Results-oriented evaluation,' 'iterative calculation,' 'infused education,' 'failure to consider the level difference,' 'lack of conceptual and principle-centered education' were mentioned as a failure factor. Most of these factors can be changed by improving and changing teachers' teaching practice. Fifth, the responses for what does a desirable mathematics instruction look like are 'classroom related to real life', 'easy and fun mathematics lessons', 'class emphasizing understanding of principle', etc. Therefore, it is necessary to deeply deal with the related contents in the training courses for the improvement of the teachers' teaching practice, and it is necessary to support not only the one-time training but also the continuous professional development of teachers.