• Title/Summary/Keyword: F.D.M.

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Luminescence properties of a new $Tb^{3+}$ ion activated long persistent phosphor (새로운 $Tb^{3+}$ 이온 활성 축광성 형광체의 발광 특성)

  • Park, Byeong-Seok;Choi, Jong-Geon
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.3
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    • pp.130-134
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    • 2009
  • A new long persistent phosphors of $CaZrO_3$ was synthesized at high temperature with weak reduction atmosphere by a traditional solid state reaction method. Photoluminescence spectra analysis showed that the $CaZrO_3$ doped with $Tb^{3+}$ emitted green-yellow emission caused by the energy level transition from the $^5D_3$ and $^5D_4$ to $^7F_1{\sim}^7F_6$. The main emission spectra of 542 nm peak by the $^5D_4{\rightarrow}^7F_5$ transition was revealed through synthesizing at high temperature in $N_2$ gas atmosphere. The afterglow emission spectra of $CaZrO_3:Tb^{3+}$ long persistent phosphores arise at 546 nm peak of narrow range. After the 254 nm ultraviolet light excitation source was switched off, the green-yellow long persistent phosphor can be observed which could last for 8 h in the limit of light perception of dark-adapted human eyes ($0.32\;mcd/m^2$).

The Change of Space Arrangement of Korea Detached House by Space Syntax - A Focusing on the Detached Houses which were Designed by Famous Architects after 1980s' - (공간구문론을 이용한 단독주택 공간배치 변화 - 1980년 이후 단독주택 중 유명건축가의 작품과 수상작품을 중심으로 -)

  • Hwang, Yong-Woon
    • Korean Institute of Interior Design Journal
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    • v.26 no.3
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    • pp.63-70
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    • 2017
  • The purpose of this study is to analyze the inner space of detached houses from 1980 to 2016. It was used 'space syntax program' for analysis and analyzed with intervals of 10 years as 1980~1990, 1990~2000 and so on. The research results will be summarized as follows: 1) Overall, all inner space that was examined shows a trend that integration space tends to increase while segregating space tends to decrease. 2) In the case of the master bedrooms(M B) in 1980s, these were composed of 2 rooms as a front room(F R) and a master bedroom type, but as time went by, the F R which was attached room to the M B disappeared. While inside space of M B attached powder-room and wardrobe instead of the F R of the M B. And F R was an integrated space at first in 1980s, but it began to change to a segregating space to protect personal privacy. 3) The dining(D) and kitchen(K) spaces were strictly separated in the 1980s but began to change to D+K and L+D+K types after 1990. 4) In the 2000s, the most typical living space in every house is continuing to change from an separate space in the other space to an integrated space where it is clearly seen from the kitchen and the dining room in the types as L+D and L+D+K.

Karyotype Analysis of Juniperus rigida Sieb. et Zucc. of Two Different Provenances in Korea (한국산(韓國産) Juniperus rigida의 두 산지(産地)의 핵형분석(核型分析))

  • Kim, Chung Suk;Chung, Woo Kyu;Ahn, Joong Kug;Jeong, Mee Jeong;Han, Chang Sook
    • Journal of Korean Society of Forest Science
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    • v.73 no.1
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    • pp.9-13
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    • 1986
  • Karyotypes are described for Juniperus rigida Sieb. et zucc, in two provenances of Gyeong-nam and Choong-puk. Chromosome numbers of two provenances, are 2n=22. The most common feature of mitotic chromosomes was shown at the chromosome 7, which has secondary constriction on the short arm. And the most differential chromosome was shown at chromosome 9 from Gyeong-nam and chromosome 5 from Choong-puk provenance which bore secondary constriction. The karyotype formulae are as follows; Gyeong-nam, Jinyang provenance race is $$K(2n)=22=2A^m+2B^m+2C^m+2D^{sm}+2E^{st}+2F^m+2^{sc}G^m+2H^m+2^{sc}I^t+2J^{st}+2K^m$$ Choong-puk, Jechun provenance race is $$K(2n)=22=2A^m+2B^m+2C^m+2D^{st}+2^{sc}E^{sm}+2F^m+2^{sc}G^m+2H^m+2I^m+2J^{st}+2K^{sm}$$.

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WEKGHTED WEAK TYPE ESTIMATES FOR CERTAIN MAXIMAL OPERATORS IN SPACES OF HOMOGENEOUS TYPE

  • Yoo, Yoon-Jae
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.1
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    • pp.25-31
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    • 1999
  • Let $\nu$ be a positive Borel measure on a space of homogeneous type (X, d, $\mu$), satisfying the doubling property. A condition on a weight $\omega$ for whixh a maximal operator $M\nu f$(x) defined by M$mu$f(x)=supr>0{{{{ { 1} over {ν(B(x,r)) } INT _{ B(x,r)} │f(y)│d mu (y)}}}}, is of weak type (p,p) with respect to (ν, $omega$), is that there exists a constant C such that C $omega$(y) for a.e. y$\in$B(x, r) if p=1, and {{{{( { 1} over { upsilon (B(x,r) } INT _{ B(x,r)}omega(y) ^ (-1/p-1) d mu (y))^(p-1)}}}} C, if 1$infty$.

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The Study of the Caries Experience of Korean Mental Disorders (정신장애자의 치아우식병역학적 조사 연구)

  • Kim, Nam-Kyu
    • The Journal of the Korean dental association
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    • v.17 no.2 s.117
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    • pp.141-145
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    • 1979
  • The author, through oral examination, had surveyed the caries experienced teeth in 250 Korean mental Disorders(153 males and 97 fameles) who took it a rule consume a Vegetable diet and had litte chance to Consume refimed Corbohydrates, unlike the Common populars. DMF rate DMFT rate index DT rate MT rate and FT rate had been calculated and Compared with Common Popular's in same ages group. Following are the obtained results 1. In the mental Disorders, Caries experience rate was 52.19% 2. D.M.F. rate and index were lower in the females than in the males 3. The Caries experience rate in the mental Disorders was lower than in the Common Populars 4. In the mental Disorders the F.T. rate was higher in females than in males D.T. rate higher in males than in females and MT rate, lower in males than in females 5. In generally D.T. rate in the mental Disorders was lower than in Controls, M.T. rate resembled as Controls and F.T. rate higher

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Study on the Preparation and Properties of 1-Step Twisted NylonYarns (1-Step 연사공정 적용 나일론 연사물의 제조 및 특성 연구)

  • Lee, Jun Young;Jeon, Jae Woo;Park, Dong Kyu;Seo, Young Ho;Im, Young Min;Oh, Tae Hwan
    • Textile Coloration and Finishing
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    • v.31 no.4
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    • pp.332-340
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    • 2019
  • Due to the change in lifestyle, new sensible materials for sportswear and outdoor are needed. This study is conducted in order to obtain the data for sensible materials through nylon twist process. 1-step nylon twisting machine was used to set the optimum twist process. DSC measurements of twisted nylon yarn showed crystallization temperatures around 170℃ and melting temperatures around 220℃. Nylon 40D/13F DTY and Nylon 50D/48F DTY showed optimal results at 160℃, 1,500 T/M(Turns per meter), and Nylon 70D/68F DTY at 160℃, 1,200 T/M(Turns per meter) after 1-step twist process. Also, Nylon 40D/13F DTY was confirmed to have inter-layer property deviation of ±5 percent.