• Korean Journal of Crystallography
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• v.9 no.2
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• pp.159-167
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• 1998

천연에서 발견되는 유색수정은 자수정, 연수정, 황수정, 청수정, 녹수정, 장미수정 등 그 색의 종류에 따라 크게 6가지로 분류되며 발색 기구에 따라 색중심(color center), 전이금속 불순물(transition metal impurity), 산란(scattering), 전하이동(charge transfer) 등 4가지로 분류된다. 이들은 천연에서 고온고압의 열수가 냉각되면서 그 안아 녹아있던 광물질이 재결정하여 생성된 것이다. 이러한 유색수정은 실험실에서도 합성되며 그 방법은 천연 수정의 생성 과정과 유사하다. 그러나 천연수정 중의 일부는 실험실에서 성장하기가 거의 불가능하기 때문에 다른 방법을 이용하여 유사한 색을 가지게 한다. 본 논문에서는 불순물 원소의 종류 및 수정 격자내의 위치, 최외각 전자의 상태에 따라 색이 달라지는 것을 고찰하고 이러한 유색수정을 합성하는 원리에 대하여 논하고자 한다.

• Proceedings of the Korea Society of Costume Conference
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• 2000.05a
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• pp.5-16
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• 2000

• Journal of the Mineralogical Society of Korea
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• v.1 no.2
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• pp.83-93
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• 1988

Amethysts in Eonyang Granite of Woolju-Kun, Kyungnam Province are frequently parallelly grown on top of preexisting smoky quartz crystallized on milky and colorless quartz crystals, which, as a whole, resemble "mushroom" in outer appearance. Fluid inclusions in the amethysts may be grouped into (1) gaseous inclusions (G>L), (2) liquid inclusions (L>G), (3) $L_{CO_2}$-bearing inclusions (L+G+$L_{CO_2}$), (4) halite-bearing inclusions (L+G+halite), (5) multiphase inclusions (L+G+halite+sylvite${\pm}$opaque mineral). In addition, euhedral K-feldspars and acicular hematite crystals are included in colorless-milky quartz and deep purple-red quartz, respectively. Filling temperatures of each type of fluid inclusions were measured as follows: $320{\sim}560^{\circ}C$ for gaseous inclusions; $100{\sim}290^{\circ}C$ for liquid inclusions; $200{\sim}310^{\circ}C$ for $L_{CO_2}$-bearing inclusions; $300{\sim}430^{\circ}C$ for halite-bearing inclusions; and $370{\sim}430^{\circ}C$ for polyphase inclusions. The finished-gem amethysts from Eonyang may be distinguished from Brazilian amethysts by the difference in filling degree of gaseous inclusions by the presence of hematite aciculae, and of $L_{CO_2}$-bearing inclusions, and also by the absence of Zebra-striation structure. They may also be differentiated from synthetic amethysts by presence of straight color banding, solid inclusions, and $L_{CO_2}$-bearing inclusions which are not found in synthetic materials.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.2
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• pp.73-77
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• 2004

The color enhancement for natural Zambian amethyst of low quality was carried out by the hydrothermal treatment method. The hydrothermal treatment conditions were as follows: reaction temperature; $300^{\circ}C$, duration; 30 hrs, filling; 40%, solvent; 6 M-HCI solution. The reddish purple amethyst of high quality was obtained under these conditions. From the result of ICP/AES, it was known that color enhancement was affected by a Fe elemental content to exist in the inside of natural Zambian amethyst. Also, from the result of UY-VIS-NIR, it was shown that the absorption peak at 550 nm after hydrothermal treatment is slightly lower than those of non-treated natural Zambian amethyst. In this study, it was known that hydrothermal treatment method was a way to suitable for increase of commercial value of natural Zambian amethyst.

• Journal of Korean Society of Transportation
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• v.18 no.4
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• pp.41-50
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• 2000

신호교차로에서 맨 우측차로의 대부분이 우회전 공용차로로 사용되는데 도로용량편람에서 우회전이 불가능한 보행자 횡단시간 비율$(f_c)$은 공용차로의 용량을 결정하는 우회전보정계수$(f_{RT})$의 산정시 중요한 요소가 된다. 그러나 이에 대한 국내의 연구는 미미하여 연구의 필요성이 있다고 생각된다. 본 연구는 유입부의 직진신호시간을 위주로 교차방향 횡단보도 내의 보행자수와 우회전차량의 통과여부를 촬영하여 분석하는 방법으로 진행되었으며, 우회전 차량이 교차도로의 보행자 횡단시간에 보행자와의 상충으로 우회전하지 못하는 시간 비율을 산정함에 있어서 횡단보도의 보행자수에 따라 우회전 차량의 통과율을 구하고 이로부터 횡단보도 보행신호시간동안에 우회전이 불가능한 시간비율을 산정했다. 연구결과는 우회전이 불가능한 시간비율이 시간당 보행자수(양방향)가 500인/시~1,500인/시로 변할 때 0.78에서 0.94사이의 값을 가지며 한국도로용량편람에서 제시한 값 0.3에서 0.9보다는 대체로 큰 것으로 나타났다. 따라서 한국용량편람에서 얻은 우회전차로의 용량은 과대 평가되는 경향이 있다.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.4
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• pp.153-158
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• 2018

The visitors' patterns of the homepages in university were classified and analyzed with the network analysis based on the hyperlinks. The numbers of visits to English web-pages were proportional to those of Korean with much less counts. The larger count of visits was confirmed for the case of colleges than the departments, showing the upper boundary of visits from the plot with the Betweenness centrality normalized by the degree. For the better visibility, well-designed hyperlinks with the proper public relations were suggested based on the quantitative analysis of visitors' count.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.10
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• pp.1071-1076
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• 2009

A wearable embroidery 'ㅂ' character shape UHF RFID tag antenna has been designed using conductive electro-thread. After testing characteristics of various electro-threads, the embroidery tag, with a T-matching structure, has been designed on a cloth with 200D(denier) electro-thread which performs electrically better. The embroidery tag on a piece of fabric or clothes made with the flexible electro-thread is a wearable tag and possible to be recognized by an RFID system. The conductivity of different deniers of electro-threads has been measured. The measured conductivity has been used for simulation and fabrication to have accurate simulation results. To verify the characteristics of the tag antenna, the return loss and reading range of the fabricated embroidery electro-thread UHF RFID tag antenna have been tested. The reading range is approximately 1.52 m.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.399-402
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• 2017

대학 내 기관별 웹페이지의 방문자 패턴을 분류하고, 하이퍼링크에 따른 네트워크 분석을 통해 방문자수와의 연관성을 연구하였다. 웹페이지 언어에 따라 영문 홈페이지는 공통적으로 낮은 방문 패턴을 보였으며, 단과대학이 개별 학과에 비해 높은 방문자수를 보였다. 웹페이지 하이퍼링크의 중심도(Centrality) 분석에서는 사이중심도(Betweenness centrality)를 정도(degree)로 정규화한 값이 방문자 수의 상한 값에 대응되는 현상이 발견되었다. 홍보효과를 위해 홈페이지 내용, 구조 설계뿐만 아니라 웹 상에 적절한 노출 전략도 도움이 됨을 알 수 있었다.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.507-509
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• 2009

New standard carnation cultivar "Jasujung" was bred from the cross of red standard cultivar "Francesco" and purple standard cultivar "Saturn" at the National Institute of Horticultural & Herbal Science. It was crossed in 1996 and finally selected in 2000 after investigation of the characteristics for 4 years from 1997 to 2000. "Jasujung", purple standard cultivar for cut flower, has good fragrance and long stem. Especially, it is strong resistance against Fusarium wilt. This cultivar is recommended to grow over $8^{\circ}C$ at night and under $25^{\circ}C$ at days.

• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.269-274
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• 2007

We established a regional ionospheric model for investigating ionospheric TEC (Total Electron Contents) variations over the Korean Peninsula during major geomagnetic storms. In order to monitor the ionospheric TEC variations, we used nine permanent GPS reference stations uniformly distributed in South Korea operated by the Korea Astronomy and Space Science Institute (KASI). The cubic spline smoothing (CSS) interpolation method was used to analyze the characteristics of the ionospheric TEC variations. It has been found that variations of TEC over the Korean Peninsula increase when a major geomagnetic storm occurred on November 20, 2003. The TEC has increased about one and a half of those averaged quite days at the specific time during a geomagnetic storm. It has been indicated that the KASI GPS-derived TEC has a correlation with the geomagnetic storm indices (eq. Kp and Dst indices).