• Journal of Educational Research in Mathematics
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• v.22 no.2
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• pp.163-178
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• 2012

The efforts to represent the numbers based on the decimal system give us fundamental understanding to construct and teach the concept network on the related knowledge of elementary and secondary school mathematics. In the process to represent natural numbers, integers, rational numbers, real numbers as decimal system, we will classify the extended decimal system. Moreover we will obtain the view to classify real numbers. In this paper, we will study the didactical significance of mathematical knowledge, which arise from process to represent real numbers as decimal system, starting from decimal system representation of natural numbers, and provide the theoretical base about the classification of real numbers. This study help math teachers to understand school mathematics in critical inside-measurement and provide the theore tical background of related knowledge. Furthermore, this study provide a clue to construct coherent curriculum and internal connections of related mathematical knowledge.

• School Mathematics
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• v.19 no.2
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• pp.319-343
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• 2017

In this study, we hope to reveal specialized content knowledge(SCK) and its features necessary to analyze student's errors and difficulties about the concept of irrational numbers. The instruments and interview were administered to 3 in-service mathematics teachers with various education background and teaching experiments. The results of this study are as follows. First, specialized content knowledge(SCK) were characterized by the fixation to symbolic representation like roots when they analyzed the concentration and overlooking of the representations of irrational numbers. Secondly, we observed the centralization tendency on symbolic representation and the little attention to other representations as the standard of judgment about irrational numbers. Thirdly, In-service teachers were influenced by content of students' error when they analyzed the error and difficulties of students. Lately, we confirmed that the content knowledge about the viewpoint of procept and actual infinity of irrational numbers are most important during the analyzing process.

• School Mathematics
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• v.19 no.1
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• pp.209-228
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• 2017

Understanding decimal numbers is important in mathematics as well as real-life contexts. However, lots of students focus on procedures or algorithms of decimal numbers without understanding its meanings. This study analyzed teaching method related to decimal numbers in a series of mathematics textbooks of Korea, Japan, Singapore and the US. The results showed that three countries except Japan introduced the decimal numbers as another name of fraction, which highlights the relation between the concept of decimal numbers and fractions. And limited meanings of decimal numbers were shown such as 'equal parts of a whole' and 'measurement'. Especially in the korean textbooks, relationships between the decimals were dealt instrumentally and small number of models such as number lines or $10{\times}10$ grids were used repeatedly. Based these results, this study provides implications on what and how to deal with decimal numbers in teaching and learning decimal numbers with textbooks.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.8 no.1
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• pp.3-9
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• 1998

본 논문에서는 2$_{m}$ -1의 메센소수 주기를 갖는 Legendre 시퀀스에 확장이론을 적용하여 유도되는 주기가 2$^{em}$ -1인 extdndre 시퀀스를 decimated m-시퀀스들의 합으로 표현하였으며 이를 이용하여 extended Legendre시퀀스를 decimated m-시퀀스들의 합으로 표현하였으며 이를 이용하여 extended Legendre 시퀀스의 선형스팬의 상한식 및 선형스팬에 관한 conjecture를 유도하였다.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.261-272
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• 2022

During the China's long history, many ethnic groups have developed their own traditions of local music which is an important part of their precious cultures. Meanwhile, each ethnic group developed its own worldview and music culture according to its unique living environment, special lifestyle and mode of production. The clarinet is a Western instrument, and has been influenced to some extent by Chinese minority culture while being introduced to China. Therefore, musicians tried to find ways of using Western musical instruments to express various elements of Chinese minority music. Focusing on two clarinet works 'The Song of Grazing Horses' by Wang Yan and 'The Sound of Pamir Clarinet Concerto' by Hu Bijing, this paper aims to analyze the musical characteristics of minority groups expressed by the clarinet in two aspects: the formation of the music style, the artistic characteristics conveyed through the works. Specifically, it consists of five parts: ethnic mode and tonality, rhythm, time signature, melody making, and imitation of animals. It also analyzes the cultural characteristics of Tajik and Mongolian music reflected in the two works in combination with living environment, mode of production, life style, and ethnic emotions. This study aims to provide a theoretical basis for composers and performers who want to understand and acquire the musical style of modern Chinese clarinet works. It also helps to find a better way to play traditional Chinese music with Western instruments.

• Journal of Elementary Mathematics Education in Korea
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• v.19 no.1
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• pp.17-37
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• 2015

In this paper, we compared and analyzed the Korean National Mathematics textbooks of the 2007 amendment curriculum and the Harcourt Math in America focused on fractions and decimals. To summarize the results of the analysis are as follows. First, both textbooks introduce fractions to the meaning of parts-whole concept, but the Harcourt Math is stronger than that of Korean Mathematics textbooks in the concept of unit fractions as a generator of fractions. Second, the fractions can be considered trivial materials - a fraction representing 1 whole, a fraction with it's denominator is 1 - were more clearly represented in our US textbooks than those of our Korean textbooks. Third, in the introduction of the term relating to the fractions, Korea is a strong point of view of the classification of fractions than the point of view of representation in comparison with the case of the United States. Fourth, the equivalent fraction and equivalent decimal concepts were described more detail in the United States of textbooks than those of the case of Korean textbooks. Finally, the approaches of fraction and decimal concepts were introduced more mathematically in the case of the United States than those of the case of Korean textbooks.

• Journal of the Korean School Mathematics Society
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• v.25 no.4
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• pp.375-396
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• 2022

In this paper, to provide an idea for the 2022 revised mathematics curriculum by restructuring the content of the 2015 mathematics curriculum, the content elements of recurring decimals of textbooks, which showed differences in the curriculum of Korea and Japan, were analyzed. As a result of this study, in Korea, before the introduction of the concept of irrational numbers, repeating decimals were defined in the second year of middle school, and the relationship between repeating decimals and rational numbers was dealt with. In Japan, after studying irrational numbers in the third year of middle school, the terminology of repeating decimals is briefly dealt with. Then, when learning the concept of limit in the high school <Mathematics III> subject, the relationship between rational numbers and repeating decimals is dealt with. Based on the results of the study, in relation to the optimization of the amount of learning in the 2022 curriculum revision, implications for the introduction period of the circular decimal number, alternatives to the level of its content, and the teaching and learning methods were proposed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.10
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• pp.72-81
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• 2011

In this paper, we proposed and designed a novel floating point converter which supports single and double precisions of IEEE754 standard. The proposed convertor supports conversions between floating point number single/double precision and signed fixed point number(32bits/64bits) as well as conversions between signed integer(32bits/64bits) and floating point number single/double precision and conversions between floating point number single and double precisions. We defined a new internal format to convert various input types into one type so that overflow checking could be conducted easily according to range of output types. The internal format is similar to the extended format of floating point double precision defined in IEEE754 2008 standard. This standard specifies that minimum exponent bit-width of the extended format of floating point double precision is 15bits, but 11bits are enough to implement the proposed converting unit. Also, we optimized rounding stage of the convertor unit so that we could make it possible to operate rounding and represent correct negative numbers using an incrementer instead an adder. We designed single cycle data path and 5 cycles data path. After describing the HDL model for two data paths of the convertor, we synthesized them with TSMC 180nm technology library using Synopsys design compiler. Cell area of synthesis result occupies 12,886 gates(2 input NAND gate), and maximum operating frequency is 411MHz.

• Education of Primary School Mathematics
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• v.19 no.3
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• pp.193-210
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• 2016

In the $10{\div}2.4$ problem situation, we could find that curious upper and middle level students' solution. They solved $10{\div}2.4$ and wrote the result as quotient 4, remainder 4. In this curious response, we researched how students realize quotient and remainder in division of decimal. As a result, many students make errors in division of decimal especially in remainder. From these response, we constructed fraction based teaching method about division of decimal. This method provides new aspects about quotient and remainder in division of decimal, so we can compare each aspects' strong points and weak points.

• Proceedings of the Korea Society of Costume Conference
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• 2003.05a
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• pp.26-26
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• 2003

학문적 논의를 중심으로 했던 1, 2세대 페미니즘에 비해, 현대의 젊은 페미니스트들에 의해 주장되고 실행되는 3세대 페미니즘은 젊은 여성들의 분노와 쾌락을 표출하고 있으며, 특히 걸 파워는 개인주의, 독립성, 적극적 섹슈얼리티 등을 통해 여성 권력을 주장한다. 본 연구는 3세대 페미니즘을 성(도덕), 문화, 인종, 공간, 성적 소수자 관점에서 파워 페미니즘, 포스트펑크 페미니즘, 3세계 페미니즘, 사이버페미니즘, 퀴어페미니즘으로 분류하고, 3세대 페미니즘을 표현하는 매체로 대중음악의 걸 파워를 선정하여, 걸 파워 의상에 표현된 여성성과 그 미적 특성을 연구했다.