• Research in Mathematical Education
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• v.16 no.4
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• pp.217-232
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• 2012

While many studies on early algebra have been conducted, there have been only a few studies on the operation sense as the fundamental element of algebraic thinking, especially the fraction operation sense. This study explored the dimensions of fraction operation sense and then investigated students' fraction operation sense. A total of 183 of sixth graders were surveyed and 5 students who showed high operation sense were clinically interviewed in order to analyze their algebraic thinking in detail. The results showed that students had a tendency to use direct calculation or employ inappropriate operation sense rather than to use the structure of operation or the relation between operations on the basis of algebraic thinking. This study implies that explicit instruction on early algebra is necessary from the elementary school years.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.31-38
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• 2016

A novel self-reference sense amplifier with parallel reading during writing operation is proposed. Read access time is improved compared to conventional self-reference scheme with fast operation speed by reducing operation steps to 1 for read operation cycle using parallel reading scheme, while large sense margin competitive to conventional destructive scheme is obtained by using self-reference scheme. The simulation was performed using standard $0.18{\mu}m$ CMOS process. The proposed self-reference sense amplifier improved not only the operation speed of less than 20 ns which is comparable to non-destructive sense amplifier, but also sense margin over 150 mV which is larger than conventional sensing schemes. The proposed scheme is expected to be very helpful for engineers for developing MRAM technology.

• East Asian mathematical journal
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• v.29 no.4
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• pp.355-392
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• 2013

Generally school algebra is to start with introducing variables and algebraic expressions, which have major cognitive obstacles to students in the transfer from arithmetic to algebra. But the recent studies in the teaching school algebra argue the algebraic thinking from an early algebraic point of view. We compare the Korean elementary mathematics textbooks with Americans from this perspective. First, we discuss the history of school algebra in the school curriculum. And Second, we investigate the recent studies in relation to early algebra. We clarify the goals of this study(the importance of early algebra in the elementary school) through these discussions. Next we examine closely the number sense in the arithmetic and the symbol sense in the algebra. And we conclude that the operation sense can connect these senses within early algebra using the algebraic thinking. Finally, we compare the elementary mathematics books between Korean and American according to the components of the operation sense. In this comparative study, we identify a possibility of teaching algebraic thinking in the elementary mathematics and early algebra can be introduced to the elementary mathematics textbooks from aspects of the operation sense.

• School Mathematics
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• v.11 no.1
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• pp.71-91
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• 2009

The purpose of this study was to analyze operation sense in detail with regard to division of fraction. For this purpose, two sixth grade students who were good at calculation were clinically interviewed three times. The analysis was focused on (a) how the students would understand the multiple meanings and models of division of fraction, (b) how they would recognize the meaning of algorithm related to division of fraction, and (c) how they would employ the meanings and properties of operation in order to translate them into different modes of representation as well as to develop their own strategies. This paper includes several episodes which reveal students' qualitative difference in terms of various dimensions of operation sense. The need to develop operation sense is suggested specifically for upper grades of elementary school.

• Journal of the Korean School Mathematics Society
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• v.8 no.4
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• pp.423-444
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• 2005

Despite the importance of number sense, computational skills have been emphasized in elementary mathematics curriculum. There is lack of research on number sense. Against this background, this study analyzed the way 137 sixth grade students coped with routine computation problems and with problems requiring number sense. Students performed better on the computation tasks than on the number sense tasks. With regard to the number sense tasks, many students had a tendency to implement direct computation rather than to use number sense appropriate to the given contexts. Students also had difficulties in making use of effective benchmarks or applying the knowledge of number and operation to various problem contexts. An implication is that students should explore multiple tasks requiring number sense as an integral part of their mathematics learning in order to develop number sense.

• Journal of Educational Research in Mathematics
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• v.19 no.4
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• pp.513-530
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• 2009

In this paper, We analyse the contents of the national mathematical curriculum, the handbook of the curriculum, and elementary school mathematics textbook for the elementary school grade 1-2 focusing on 'number sense'. At first, we identify the meaning and the elements of number sense through analysing studies which are related to number sense. Number sense includes understanding the meaning of number, operation, and estimation, and the ability of applying numbers, operation and estimation on the context. Number sense consists of the elements of the contents and the elements of the processes. Secondly, with the elements of number sense which we have identified, we analyse the contents of the national mathematical curriculum, the handbook of the curriculum, and elementary school mathematics textbooks, and then criticize the contents. We find some problems as a result of the analysis : the range of number sense is unclear, the word 'number sense' is not used consistently, the elements used are limited, and the contents of the textbook are materialized inconsistently and poorly.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1181-1184
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• 2003

This paper proposes a new Sense Amplifier for MRAM. Current Sense Amplifier employs a latch-type circuit to amplify a signal from the selected memory cell. The proposed Sense Amplifier simplifies the circuit by amplifying the signal using cross-coupled PMOS transistors. It shows the same operation speed as the latch-type Sense Amplifier in simulation and occupies only 85% of the area taken by the latch-type Sense Amplifier.

• Journal of Elementary Mathematics Education in Korea
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• v.20 no.4
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• pp.737-760
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• 2016

This study analyzed the 2009 revised curriculum 6th grade math geometric domain and developed virtual operation tool contents based RME theory. These materials were examine to find out how to effect on the spatial sense and mathematical attitudes by applying it to teach the 6th grade students. The results were as follows. First, it is more effective for improving spatial sense to study mathematics based RME theory with virtual operation tool contents than normal one. This means that mathematics study based RME theory with virtual operation contents overcomes the limitations of flat learning environment. And it is great educational and effective method for students to improve their spatial sense. Second, it is more effective for improving mathematical attitudes to study mathematics based RME theory with virtual operation tool contents than normal one. This means that Mathematics study based RME theory with virtual operation contents makes student more participate learning actively. It helps the students who have passive learning habits to have self-directed learning habits, ability to cooperation and communicate. The results of this study suggest that mathematics study based RME theory is very helpful for student to improve their spatial sense and have positive effect on self-concept in mathematics, attitudes toward mathematics and improving study habits in mathematical attitudes.

• Korean Journal of Cognitive Science
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• v.3 no.2
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• pp.225-248
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• 1992

In this paper, word sense disambiguation methods utilizing a knowledge base based on a semantic network are introduced. The basic idea is to keep track of a set of paths in the knowledge base which correspond to the inctemental semantic interpretation of a input sentence. These paths are called the semantic paths. when the parser reads a word, the senses of this word which are not involved in any of the semantic paths are removed. Then the removal operation is propagated through the knowledge base to invoke the removal of the senses of other words that have been read before. This removal operation is called recusively as long as senses can be removed. This is called the recursive word sense removal. Concretion of a vague word's concept is one of the important word sense disambiguation methods. We introduce a method called the path adjustment that extends the conctetion operation. How to use semantic association or syntactic processing in coorporation with the above methods is also considered.

• East Asian mathematical journal
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• v.40 no.2
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• pp.183-207
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• 2024

This study is a case study that considered fractional senses and fraction operation abilities for 107 gifted students in elementary school classes. In order to find out the fractional sense, in the first question comparing the sizes of fractions 2/3 and 4/5, the students showed a variety of strategies, but the utilization rate of strategies excluding reduction to a common denominator did not exceed 50%. The second question can be solved by using the first question. It is a problem of finding two fractions by selecting four from six numbers 1, 3, 4, 5, 6, and 7 to create two fractions of which sum does not exceed 1. The percentage of correct answers to this question was about 27% (29 out of 107). Only 5 out of 29 students found answers using the first question, and the rest of the students sought answers through trial and error in various calculations. It shows that the item arrangement method from a deductive perspective has no significant effect on elementary school students. The percentage of correct answers was about 27% in the questions to find out the fraction operation ability-the question of drawing a 4/3 bar using a given 3/8-sized bar and 30.7% (23 out of 75) of the students who had wrong answers showed insufficient splitting operation. In addition, it has been shown that the operation of partitioning and iterating to form numerical senses and fractional concepts related to the fractions of the students has no significant impact.