• ETRI Journal
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• 제38권6호
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• pp.1135-1144
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• 2016

Fractal antenna arrays are geometry-based thinned arrays having multiband applications. The major challenge of these arrays is their large number of elements at higher expansion factors. This article presents the thinning of fractal antenna arrays while maintaining an appropriate balance between the side lobe level and beam width by using various quantized fractal distribution functions. A 2D square fractal antenna array and 3DSierpinski gasket antenna array are considered in this article to validate the proposed distribution functions. Nearly one third of the antenna elements are thinned in each successive iteration except in the case of a one-count distribution function. The proposed technique can simplify practical implementation and exhibits better performance for various parameters such as the side lobe level, side lobe angle, and half power beam width than fully populated fractal antenna arrays.

• Nuclear Engineering and Technology
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• 제8권1호
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• pp.41-47
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• 1976

Ge(Li) 검출기를 사용한 비파괴 방사화분석법을 이용하여 담수어중 수은 및 기타 미량원소들의 현재 함량 준위를 조사하다. 분석결과에 의하면 지역에 따라 수은의 함량이 크게 변하였으며 이 변화는 아마 지역적인 오염원에 의한 것으로 생각된다. 그리고 분석결과로 부터 미량원소들 중 어떤 원소들 사이에는 뚜렷한 상관관계가 있음을 알았다. 수은 오염의 중요한 원인으로 무연탄 연소가 고려될 수 있을 것으로 생각되어 수종의 무연탄을 분석하였다.

• 한국지구과학회지
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• 제32권7호
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• pp.707-718
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• 2011

보성-화순지역 하상퇴적물에 대한 지질집단별 자연배경치와 지구화학적 특성에 대해 연구하였다. 이를 위해 1차 수계를 따라 하상퇴적물시료 186개를 채취하였고, 실험실에서 자연건조 시킨 후, XRF, ICP-AES, NAA분석을 실시하였다. 하상퇴적물의 지질집단별 자연배경치와 지구화학적 특성을 알기 위해, 시료를 화강암질편마암(GGn)지역과 반상변정질편마암(PGn)지역으로 분리하였다. 화강암질편마암지역의 주성분원소 함량은 $SiO_2$ 45.5-73.09 wt.%, $Al_2O_3$ 12-20.76 wt.%, $Fe_2O_3$(T) 3.72-8.85 wt.%, $K_2O$ 2.38-4.2 wt.%, MgO 0.75-2.77 wt.%, $Na_2O$ 0.78-1.88 wt.%, CaO 0.27-2.1 wt.%, $TiO_2$ 0.56-1.72 wt.%, $P_2O_5$ 0.06-0.73 wt.% and MnO 0.03-0.95 wt.%이고 반상변정질편마암지역의 주성분원소 함량은 $SiO_2$ 43.74-70.71 wt.%, $Al_2O_3$ 11.54-25.05 wt.%, $Fe_2O_3$(T) 3.44-13.46 wt.%, $K_2O$ 2.08-3.86 wt.%, MgO 0.65-2.99 wt.%, $Na_2O$ 0.63-1.7 wt.%, CaO 0.35-2.07 wt.%, $TiO_2$ 0.68-4.17wt.%, $P_2O_5$ 0.1-0.31 wt.% and MnO 0.07-0.33 wt.%이다. 화강암질편마암지역 하상퇴적물의 위해원소 함량은 크롬 41.7-242 ppm, 코발트 7.6-25.1 ppm, 니켈 12-61 ppm, 구리 10-47 ppm, 아연 48.5-412 ppm, 납 17-215 ppm이고 반상변정질편마암지역은 크롬 29.6-454 ppm, 코발트 5.9-53.7 ppm, 니켈 8.7-287 ppm, 구리 6.4-134 ppm, 아연 43.6-370 ppm, 납 15-37 ppm이다. 화강암질편마암지역에서 크롬은 MgO와 코발트는 $Al_2O_3$, $Fe_2O_3$(T), MgO와 니켈은 $Fe_2O_3$(T), CaO, MgO와 높은 상관성을 가지나, 구리, 아연, 납은 비교적 낮은 상관성을 보였다. 반상변정질편마암지역에서 일반적으로 크롬, 코발트, 니켈, 구리는 주성분원소와 대부분 높은 상관성을 보였으나, 아연과 납은 낮은 상관성을 보였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권4호
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• pp.31-40
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• 2015

Various types of inorganic and organic colloids are present in natural water including groundwater. Previous studies showed that Fe, Mn and Al are colloid-forming elements and dissolved concentrations can be erroneous for these elements if water samples are not properly filtered. Dissolved concentrations of elements including Ca, Na, Mg, K, Fe, Mn, Si and Al in groundwater from alluvial and bedrock aquifers, and surface water near Nakdong River were determined to evaluate effects of colloids on dissolved concentrations in natural water samples using various pore sizes of filters. Groundwater is mostly anoxic and have elevated concentrations of Fe and Mn, which provides a unique opportunity to observe the effects of colloids on dissolved concentrations of colloid-forming elements. Membrane filters with four kinds of pore sizes of 1000 nm, 450 nm, 100 nm, and 15 nm were used for filtration of water samples. Concentrations of dissolved concentrations in each filtrate did not show significant differences from 1000 nm to 100 nm. However, concentrations of all elements considered were decreased in the filtrates obtained using 15 nm pore size filters by 10 to 15% compared to those using 450 nm except for bedrock groundwater. Al in surface water showed a distinct linear decrease with the decrease of filter pore sizes. These results showed that 100 nm pore size had little effect to remove colloidal particles in alluvial groundwater and surface water in our study. In contrast, significant concentration decreases in 15 nm pore size filtrates indicate that the presence of 15 to 100 nm colloidal particles may affect determination of dissolved concentrations of elements in natural water.

• 한국환경과학회지
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• 제27권7호
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• pp.543-554
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• 2018

From November 2013 to December 2016, ambient fine particulate matter ($PM_{2.5}$) was sampled in the downtown area of Jeju City, South Korea, which has seen rapid urbanization. The atmospheric concentrations of elements were measured in the $PM_{2.5}$ samples. This study focused on Cd, Cr, Cu, Mn, Ni, Pb, As, Sb, Sn, V, and Zn. The concentrations of Al, Na, K, Fe, Ca, Mg, Sr, and La were also obtained for reference. The objectives of this study were to examine the contributions of these elements to $PM_{2.5}$ concentrations in downtown Jeju City, and to investigate the inter-element relationships and the elemental sources by using enrichment factors and principal components analysis (PCA). A composition analysis showed that the 19 elements constituted 6.65 % of the $PM_{2.5}$ mass, and Na, K, Al, Fe, Ca, Mg, and Zn constituted 98 % of the total ion mass. Seasonal trend analysis for the sampling period indicated that the concentrations of the elements increased from November to April. However, no substantial seasonal variations were found in the concentrations of the elements. The composition ratios of some elements (Cu/Zn, Cu/Cd, Cu/Pb, V/Ni, and V/La) were found to be out of range when compared to the literature from other urban areas. The ratios between the elements and the PCA results showed that local contaminant sources in Jeju City rarely influence the composition of $PM_{2.5}$. This suggests that the major sources of $PM_{2.5}$ in Jeju City may include long-range transport of fine particulate matter produced in other areas.

• 복식문화연구
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• 제30권3호
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• pp.348-365
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• 2022

The purpose of this study is to develop Korean clothing designs that can satisfy future consumer's needs based on the elements extracted through the content analysis method in a study on the design elements expressed in traditional outfits in the 2010s. To this end, data analyzing Hanbok in wedding magazines were used, and after extracting design elements, research methods for empirical design development were used. After subclassifying the major design elements, factors with a steady increase in frequency and appearance rate were identified. Through this, five elements capable of aesthetic sampling were extracted by complex expression methods and expressed in a total of seven combinations. The types extracted from the design elements are items, silhouette, top shape, skirt shape, skirt length, mixed items with increasing frequency. In the element of color, the adjacent color harmony, which showed the highest frequency of color, and the white-blue harmony, which showed an increase among them, were extracted. When using materials, top and skirt have similar usage rates of the same and different materials, so both contents were extracted, and many patterns were arranged in the top and the whole, but these three were extracted because there were increasing cases where there were no patterns. In the case of decoration, embroidery, pintuck, sakdong, applique, lace, ribbon on the top, silver foil and print on the skirt were extracted. Through this study, it was possible to propose a future Korean costume design model.

• 한국문헌정보학회지
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• 제58권1호
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• pp.199-224
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• 2024

해외 소장 한국 고지도는 자료의 물리적 접근이 어려운 점과 고지도의 추상성 등으로 인해 연구하는데 제약이 있다. 따라서 서지사항이나 기술요소에 좀 더 자세하고 전문적인 특성이 반영되어 이를 통해 고지도 연구에 도움이 되는 정보가 제공되어야 한다. 본 연구는 한국고지도의 계통을 연구할 때 필요한 고지도의 요소를 해주신본 계통의 고지도를 바탕으로 분석하여 고지도 기술요소로 도출하였다. 그리고 이렇게 도출된 총 8개 영역의 56개 고지도 기술요소를 바탕으로 국내에 잘 알려지지 않은 해외 소재 주요 고지도인 프랑스국립도서관 소장 「영연도」에 적용한 후, 고지도 연구의 접근성과 활용성에 도움이 되는 고지도 기술요소 최종안을 제안하였다.

• 한국광물학회지
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• 제6권2호
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• pp.80-93
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• 1993

Jido kaolin deposits developed in the rhyolitic tuff of Cretaceous are located in the western part of Sinan-gun, Jeonranam-do. Jido kaolin deposits is predominantly composed of pyrophyllite, kaolinite and illite. On the basis of mineral assemblage Jido kaolin deposits can be divided into three alteraion zone from the center of alteration to the margin; kaolinite, kaolinite-pyrophyillite and pyrophyillite zones. Discriminant analysis show that $Al_2O_3$, $K_2O$, $Na_2O$, CaO of major elements are discriminant elements classifying kaolinite, kaolinite-pyrophyllite and pyrophyllite zones, while in case of trace elements Cr, Ni, Sc, Zn, and Zr are discriminant elements. Kaolin deposits has been formed by the hydrothermal alterations of the volcano rocks such as rhyolitic tuff and lapilli tuff, in late cretaceous. On the basis of the results of X-ray diffraction analysis, the deposits can be classified into three types of minerals assemblages; kaolinite, kaolinite-pyrophyllite and pyrophyllite zones. All the assemblages contain quartz and muscovite, but the kaolinite zone contains kaolinite, illite and chlorite, the kaolinite-pyrophyllite zone contains kaolinite, pyrophyllite and the pyrophyllite zone contains illite and pyrite.

• 복식문화연구
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• 제4권3호
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• pp.349-359
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• 1996

The research was designed to find out the effects of design elements ; ①color, ②pattern, on image perception of clothing by using a qualitative depth interview method. The subjects were 40 women who lived in Taejon and aged 20 to 40. The interview results were both hand recorded and tape recorded for further analysis by researchers and judge groups. And the results were as follows. 1. The most preferred colors appeared to be blue and black, while stripes, checks and flowers were most favorite patterns. 2. There were individual difference in color and pattern perception, however the color image of yellow was brightness, red was dashing, green comfortable, blue cool, and black tightness. The image of geometric pattern was modesty and natural motif pattern was dynamics. 3. The tow major forces which affected the image of design elements were appeared as followed : 1) Color images affected by the image of natural objects which obtained the color. 2) Individuals past experience and emotional status also affected the personal image perception. 4. The color and pattern preference for the Koran traditional customes and Western tow piece were significantly different and this result imply cultural stereotyping on image perception of design elements. On conclusion, the results supported the research model of form perception and image evaluation.

• 디자인학연구
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• 제16권3호
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• pp.381-390
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• 2003

이 논문은 산후관리시설의 현 실태와 시설을 이용한 사용자들의 만족도를 비교 조사하여 산후관리시설의 효율성과 만족도를 높이기 위한 기초 자료를 제공하는 것을 목적으로 연구된 것이다. 상세한 연구를 위해 산후관리시설 중 산모실로 연구 대상을 한정 하였다. 이 논문을 위한 기초 자료는 240명의 산모를 대상으로 한 설문조사와 산후관리시설에 대한 관찰 조사를 병행하여 수집하였다. 설문조사는 2003년 3월 8일부터 2003년 3월 29일에 걸쳐 실시되었고 이 자료는 SPSS-WIN을 이용하여 빈도분석 하였다. 논문의 주요 결론은 다음과 같다. 첫째, 사용자의 만족도를 결정하는 부분에 있어 산모실의 소음, 통풍, 자연채광 같은 환경요소가 대단히 중요함을 알 수 있었다. 둘째, 산모실 면적, 창문의 유무, 개인 화장실 및 샤워실 등의 기능적인 요소들도 산모들의 이용 만족도에 중요한 요소가 됨을 발견 하였다.