• 한국생산제조학회지
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• 제8권4호
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• pp.130-135
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• 1999

The main scale of linear encoder greatly effects on the precision of displacement measurement. Especially when needing the long range measurement the length of main scale should be increased accordingly. In this paper we propose a linear encoder that uses laser interference pattern as main scale for long range measurement. The linear encoder is similar to Michelson interferometer excepting that the reference mirror is tilted so as to obtain interference fringe pattern and a grating panel is attached on a quadratic photo diodes. Four kinds of grating having phase difference of 0. $\pi$/4, $\pi$/2, 3$\pi$/4 are arranged on the panel. The experimental results show that signals of quadratic photo diode A, B, {{{{ {-}atop {A } }}}} and {{{{ {- } atop {B } }}}} are cosine wavelike and successive signals have phase difference of $\pi$/4 each other. So the proposed method can achieve improved measurement resolution.

• 복식문화연구
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• 제6권2호
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• pp.141-152
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• 1998

In the result of classification body types for 100 adult women by direct measurements and antropometric measurements, the mean of weight is bigger than he mean of weight of 97'. So modern 20's women is more than than 94'. In the result of factor analysis, 5 factors were extracted (horizontal sizes, vertical sizes, and degree of shoulder) from exponent sizes of the antropometric measurements item, and another 5 factors were extracted (thick of body, horizontal form of the torso, silhouette of the torso, and size of abdomen) from direct measurements item. The body types are classified into 4 types by cluster analysis in the result of direct measurement item, and another body types are classified into 5 types by antropometric measurement item, it was classified into the horizontal size and the shape and silhouette of torso, and by direct measurement item, it was only classified into the vertical and horizontal size. So for the patternmaking of clothing, it is more adoptable the classification of body by antropometric measurement item than direct measurement item.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 춘계학술대회 논문집
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• pp.170-174
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• 1999

The main scale of linear scale greatly affects on the precision of displacement measurement. Especially when needing the long range measurement, the length of main scale should be increased accordingly. In this paper, we propose a linear scale that uses laser interference pattern as main scale for long range measurement. The linear scale is similar to Michelson interferometer excepting that the reference mirror is tilted so as to obtain interference fringe pattern and a grating panel is attached on a quadratic photo diodes. Four kinds of grating having phase differences of 0, $\pi$ /4, $\pi$ /2, 3 $\pi$ /4 are arranged on the panel. The experimental results show that signals of - quadratic photo diode, A, B,$\overline{A}$ and $\overline{B}$ are cosine wavelike and successive signals have phase difference of $\pi$/4 each other. So the proposed method can achieve improved measurement resolution.

• 보건의료산업학회지
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• 제5권3호
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• pp.145-155
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• 2011

This study is Dental Hygiene Department of G University for comprehensive dental hygiene control and treatment weekly for four weeks from September 16 to October 20, 2010, excluding those who visited for ambulatory treatment of systemic diseases. For the 90 subjects, we performed oral examination, measured Simplified Oral Hygiene Index (S-OHI), Modified Patient Hygiene Performance (PHP-M), and O' Leary Index, and applied comprehensive dental hygiene control. First, as to the change of OHI according to age, the index in the 1st measurement was 3.43 in those under 35 and 3.17 in those aged 35 or older, so it was higher in the younger group, but in the 2nd measurement it was 1.89 in those under 35 and 2.14 in those aged 35 or older, and in the 3rd measurement it was 1.22 in those aged 35 or older, so it was higher in the older group. Second, as to the change of PHP-M according to age, the index in the 1st measurement was 50.35 in those under 35 and 43.16 in those aged 35 or older, soit was higher in the younger group, but in the 2nd measurement it was 31.97 in those under 35 and 28.88 in those aged 35 or older, and in the 3rd measurement it was 21.31 in those aged 35 or older, so it was higher in the older group.

• 대한지구과학교육학회지
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• 제5권2호
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• pp.139-147
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• 2012

The purpose of this study was to explain how extraordinary the scientific technology or our ancestor was from the modern perspective by remodeling the most unique astronomical instrument, So-ganui (小簡儀), developed in the Sejong Period (世宗時代) after being examined with contemporary and the principles of the science and observational technology would be properly understood and measured directly. When measuring the altitude of the sun and azimuth using So-ganui, it was adjusted with the horizontal coordinate system and measured using Jipyeonghwan (地平環), Ipeunhwan (立運環) and Guyhyeong (窺衡). Based such measuring principles, the measurement accuracy proposed using So-ganui are as follows. The remodeled So-ganui produced approximately ${\pm}0.29$ degrees error on average at high altitude while in measuring the azimuth degrees, there was difference of ${\pm}0.35$ degrees. Since the theoretically, the measurement error for So-ganui was ${\pm}0.5$ degrees, the remodeled So-ganui could accurately measure at the high altitude compared to So-ganui from the Sejong period. In the study, So-ganui, which has disappeared, has been remodeled in modern perspective to be used as the educational material to accurately understand the principles of science and measurement technology from the Sejong period. The findings could contribute to raising the reputation in the astronomical observations from the documents from the Sejong period. Furthermore, this study has materialized the celestial and sky our ancestors have viewed with the observational principles of their times, on the computer screen via a webcam, bringing out interest in the traditional science for the students.

• 품질경영학회지
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• 제21권2호
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• pp.48-60
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• 1993

We have depended upon the quantitative analysis for productivity measurement. and excluded the qualitative analysis from productivity measurement. But I think that the qualitative analysis must be considered so as to get a effective productivity measurement This paper intened to establish improvement productivity measurement adopted quality cost of all the qualitative elements.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제5권2호
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• pp.99-106
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• 2001

We have known that ethno-mathematics is a field of a study that emphasizes the socio-cultural environment in which a person "does" mathematics as stated by D'Ambrosio(Ethno mathematics and its Place in the History and Pedagogy of Mathematics, 1985). Measurement is an important mathematical topic, which leads students to relate math to the eal-world applications, particularly with socio-cultural aspects. The purpose of this article is to review the history of the measurement system in Korea briefly and to adapt the measurement system into real-world problems so that children acquire measurement knowledge in the most natural way.

• 산업융합연구
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• 제1권2호
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• pp.95-105
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• 2003

"All things possibly could be measured.", measurement is a essential part in all kinds of industry, especially in manufacturing. Korean Industrial Standard has been established and announced in September, 1961. Measurement has been emphasized. But until now, measurement hasn't been located to the core of manufacturing in domestic. So, this study suggests improvement guide line for the multilateral problems of measurement system based on the investigation of 146 small and medium-sized enterprises in April, 2002.

• 한국대기환경학회지
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• 제15권6호
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• pp.713-725
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• 1999

Air pollutants($SO_2$, NOx, $O_3$ and aerosol number) were measured using an aircraft to investigate the characteristical features of long-range transport of sulfur compounds over the Yellow Sea for the periods of 26~27 April and 7~10 November in 1998. The mean $SO_2$ concentrations of April 26th~27th and November 7th~10th flight were 0.6~1.8 ppb and 0.5~8.3 ppb, respectively, and the sulfur transport was largely limited to the atmospheric boundary layer. Especially, $SO_2$ increased up to 8.3 ppb altogether with the increase of particle number concentraton especially on November 8, 1998. In addition, $O_3$ was remarkably decreased against the increase of $SO_2$and particle number concentrations. This enhanced $SO_2$ concentration occurred in the low level westerlies in association with the anticyclonic flow over Southern China and the cyclonic circulation over Manchuria. Aerosol analyses at Taean site also showed that sulfate concentration increased 2~3 times higher than those of another sampling days, which could suggest possible interactions between aerosol particels and tropospheric ozone. A rigorous evaluation will be possible after the more intensive measurements and quantitative analyses with detailed chemistry model including the postulated heterogeneous mechanism.

• 전기화학회지
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• 제2권1호
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• pp.23-26
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• 1999

백금$(Pt)/0.1M\;H_2SO_4$, 전해질 계면에서 교류임피던스 측정과 위상이동 방법을 사용하여 Langmuir 흡착등온식을 정성적으로 해석하였다. 위상이동$(\phi)$은 음전위(E<0)와 주파수(f)에 따르며, Pt 일전극(음극)에 흡착된 수소원자$(H_{ads})$의 표면피복율$(\theta)$에 반비례한다. 중간주파수대$(1\~100 Hz)$에서 위상이동 변화$(\phi\;vs.\;E)$는 Langmuir 흡착등온식$(\theta\;vs.\;E)$의 계산과 해석에 사용할 수 있는 실험적인 방법이다. $Pt/0.1M\;H_2SO_4$ 전해질 계면에서 흡착평형상수(K)와 표준자유에너지$({\Delta}G_{ads})$는 각각 $3\times10^{_4}$와 20.1kJ/mol이다.