• Title/Summary/Keyword: 국제단위계

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국제단위계(SI)해설

  • 정낙삼
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.8 no.2
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    • pp.66-74
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    • 1997
  • 현재 세계 대부분의 나라에서 사용하는 국제단위계는 우리가 그동안 미터법이라고 부르던 단위계가 현대화 된 것이라고 보면 된다. 이 국제단위계를 보통 'SI'라고 하는데 이는 불어 Le Sys- teme International d'Unites에서 온 약어로 국제 공통으로 이렇게 표시하기로 했다. 즉 이 단위계의 이름을 우리나라 말로는 '국제단위계'이지만 영어로는 'The International System of Unit's로 표시 하는 등 각 나라마다 다를 수 있으나 전 세계 모든 나라가 공통으로 'SI'라고 부르기로 한 것이다. 국제단위계(SI)의 시초는 1790년경 프랑스에서 발명된 '미터계'이며, 이 미터계는 1875년 17개국 이 미터협약(Meter Convention)에 조인함으로써 공시화되었다. 이 미터계로부터 분야에 따라 여러 개의 하부 단위가 생겼으며 이에 따라 많은 단위들이 나타나게 되었는데, 그 한 예가 1881년 과학분 야에서 사용하기 위해 만든 CGS계이며, 이는 센티미터, 그램 및 초에 바탕을 두고 있다.

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Redefinition of the SI Base Units with Fundamental Constants (기본상수를 이용한 SI 기본단위의 재정의)

  • Lee, Ho Seong
    • Korean Journal of Optics and Photonics
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    • v.30 no.4
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    • pp.133-141
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    • 2019
  • Revision of the International System of Units (SI) in terms of fundamental constants was achieved by the 26th General Conference on Weights and Measures (CGPM) in November 2018. Four base units (kilogram, ampere, kelvin, and mole) of SI were redefined by fixing the values of the Planck constant h, elementary charge e, Boltzmann constant k, and Avogadro constant $N_A$ respectively. In this paper the scientific principle for redefining the kilogram from the Planck constant with the Kibble balance is explained as an example. The revised SI takes effect on May 20, 2019.

A Study on Correct Usage of SI Units and School Education for Units (SI 단위계 사용의 정확성과 단위교육의 필요성에 관한 연구)

  • Kim Seong-Gon;Song Chul-Ki
    • Journal of Engineering Education Research
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    • v.7 no.2
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    • pp.51-59
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    • 2004
  • The signs have been used as the world-wide common language. Because all units have their own meanings, their usage should be kept correctly. This paper shows how middle school students know and keep the usage of SI units. And this paper shows the necessity of teaching the students correct units in their schools.

An Analysis of Capacity and Weight in the Elementary Mathematics Textbooks (들이와 무게의 단위에 대한 초등학교 수학 교과서 분석)

  • Kwon, MiSun;Pang, JeongSuk
    • School Mathematics
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    • v.19 no.2
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    • pp.385-403
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    • 2017
  • This paper analyzed the units of capacity and weight in the mathematics textbooks in terms of units, relationship between the units, and the need of standard units. The results of this study showed that there were differences in the representation of the units, the notation of units, the types of units, and the representation of basic amount of units in the mathematics textbooks developed by the 5th, 6th, 7th, 2007 revised, and 2009 revised national mathematics curriculum respectively. The mathematics textbook developed by the 2009 revised mathematics curriculum was found to be generally consistent with the International System of Units (SI). However, the way of defining 1kg through the weight of water was found to be different from the SI. The relationship between the units was consistently described only with a written sentence in the previous mathematics textbooks, but the 2009 revised mathematics textbook presents questions and pictures to foster students' understanding of the relationship. Finally, activities and questions are required for students to recognize the universality and convenience of the standard units through the inconvenience of arbitrary units. Based on these results, this paper provides implications for the development of mathematics textbooks in the units of capacity and weight.