• 한국수학교육학회지시리즈B:순수및응용수학
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• 제6권1호
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• pp.13-16
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• 1999

We introduce the notion of the $\omega$-derived set and $\omega$-dense, and investigate some of their properties.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권1호
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• pp.31-37
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• 2013

Purpose: Maxilla and mandible have different patterns of cortical and trabecular bone and different bone mineral densities, even though both are components of the jaw bone. However, cellular differences between maxilla- and mandible derived osteoblasts (OBs) have rarely been studied. We hypothesize that maxilla- and mandible-derived OBs show different responses to $17{\beta}$-estradiol (E2), which is one of the critical factors for bone formation. This study compares skeletal site-specific cell responses between maxilla- and mandible-derived human OBs to E2. Methods: Maxilla- and mandible-derived OBs derived from an identical donor were separately isolated from a total of five normal healthy subjects aged 18~44 years old, cultured with a treatment of 100 nM estrogen. The responses between maxilla- and mandible-derived OBs to E2 were evaluated and compared using cell proliferation, alkaline phosphatase (ALP) activity and gene expression of osteoprotegerin (OPG), ALP, insulin-like growth factor-1 (IGF-1), and estrogen receptor ${\alpha}$ ($ER{\alpha}$). Results: E2 did not have any distinct effects on the proliferation of both types of OBs. Mandible-derived OBs exhibited higher ALP activity than maxilla-derived OBs in the non-treated condition, which was common in all tested individuals. ALP activities of both types of OBs showed a minor increasing tendency with the treatment of E2, even though there was no statistical significance in some specimens. The gene expression of OB by E2 was diverse, depending on the individuals. There was increased expression of OPG, IGF-1, or $ER{\alpha}$ gene in the part of subjects, which was more repeated in maxilla-derived OBs. In particular, OPG or ALP induction by E appeared less frequently in mandible-derived OBs. Conclusion: Current results revealed that E2 affects maxilla- and mandible-derived OBs into facilitating the osteogenic process despite individual differences. Mandible-derived OBs are less sensitive to bone-forming gene expression by E2.

• International Journal of Oral Biology
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• 제37권1호
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• pp.9-16
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• 2012

The aim of this study was to evaluate surface characteristics and biological properties of the dentin -derived hydroxyapatite (HA) coating on titanium substrate. Dentinderived HA was obtained from extracted human teeth using a calcination method at $850^{\circ}C$. The commercially pure titanium (cp-Ti, ASTM Grade II) was used as a metallic substrate and a radio frequency magnetron sputtering method was employed as a coating method. Scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were utilized to investigate the coating aspects and composition. Atomic forced microscopy (AFM) and a surface profiler were used to assess the surface morphology and roughness. Corrosion tests were performed in phosphate-buffered saline at a $36.5{\pm}1^{\circ}C$ in order to determine the corrosion behavior of the uncoated and coated specimens. The biocompatibility of dentin-derived HA coated specimens with fetal rat calvarial cells and human gingival fibroblasts was assessed by SEM and cell proliferation analysis. The results showed that the dentin-derived HA coatings appeared to cover thinly and homogeneously the surfaces without changing of the titanium substrate. The EDX analysis of this the coating surface indicated the presence of Ca and P elements. The mean surface roughness of cp-Ti and dentin-derived coating specimens was $0.27{\mu}m$ and, $1.7{\mu}m$, respectively. Corrosion tests indicated a stable passive film of the dentin-derived HA coating specimens. SEM observations of fetal rat calvarial cells and human fibroblast cells on coated surfaces showed that the cells proliferated and developed a network of dense interconnections. The cells on all specimens proliferated actively within the culture period, showing good cell viability. At day 1 and 3, dentin-derived coating specimens showed 89% and 93% cell viability, respectively, when normalized to cp-Ti specimens. These results suggest that dentin-derived HA coating using the RF magnetron sputtering method has good surface characteristics and biocompatibility.

• 한국토양비료학회지
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• 제32권3호
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• pp.211-214
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• 1999

영남지역의 대표적인 밭토양의 모암지대별 특성차이를 알기 위해 모래입자의 형태적 특성인 구형도를 조사하고 토양수분특성곡선을 구한 결과는 다음과 같다. 모래인자의 형태적 특성인 구형도는 모래입자의 크기에 관계없이 화성암에서 0.56~0.61, 퇴적암에서 0.63~0.67의 범위로 퇴적암 유래 토양에서 높게 나타났으며 화성암 유래 토양의 경우에는 입자가 작을수록 구형도가 더 낮은 경향을 보였다. 토양수분특성곡선은 사양질에서보다 식 양질토양에서 모암간에 큰 차이가 있었고, 화성암에서보다는 퇴적암에서 유래된 토양이 보수력이 높은 경향이었다. 유효수분율에 의하여 scale을 변환시킨 결과 토성이나 모암지대에 상관없이 토양수분 특성곡선이 거의 변화를 보이지 않는 것으로 나타났다. 그러나 퇴적암지대의 식양질 토양에서는 조금 벗어난 값을 보였다.

• 한국측량학회지
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• 제36권1호
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• pp.1-8
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• 2018

To compensate for the shortcomings of spirit leveling, research on the determination of GNSS (Global Navigation Satellite System)-derived orthometric height has been actively carried out. However, most analyses were primarily performed inland. In this study, the influences of the arrangement of control points, observation duration, and geoid model on the accuracy of the GNSS-derived orthometric height have been analyzed to suggest the proper method to apply the determination of GNSS-derived orthometric height to the leveling loop disconnected area. As a result, it was found that two known points located near the unknown points need to be fixed in the leveling loop disconnected area. Further, 3 cm level of accuracy can be achieved if the GNSS survey is performed over two days, for four hours per day. In terms of the geoid model, the latest national geoid model should be applied rather than the EGM08 (Earth Gravitational Model 2008) to minimize regional bias and increase accuracy. Future research is necessary to apply the determination of the GNSS-derived orthometric height technique as a method to connect with the islands because the vertical reference system used inland and that used for the islands in Korea are still different.

• 한국균학회지
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• 제35권1호
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• pp.43-46
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• 2007

식물에 대해 병원성균이 아닌 자연계에서 존재하는 진균류로 부터 세포벽 성분을 분리하여 식물의 유도 저항성을 유도하는 엘리시터로써의 가능성을 시험하였다. 그 결과 선발된 진균 세포벽 성분이 감자에서 종래 알려진 어떤 엘리시터 보다도 아주 낮은 농도처리에서도 활성산소와 파이토알렉신 생성을 다량 유도하였다. 뿐 만 아니라 감자괴경을 이용한 병저항성 생물검정에서도 우수한 유도저항성이 발현되었음을 확인하였다. 그러므로 자연에서 분리된 일반적인 균주의 세포벽물질 엘리시터도 식물체의 유도저항성을 효과적으로 유도할 수 있는 새로운 식물병방제제로서의 개발 가능성이 있음을 시사하였다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제1권1호
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• pp.31-42
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• 2012

현재까지 대부분의 한국어처리시스템에서는 가급적 많은 접미파생명사를 사전에 등재하여 처리하였다. 그러나 접미사는 생산성이 높기 때문에 모든 접미파생명사를 사전에 등재하는 것은 한계가 있다. 따라서 접미파생명사의 의미 분석을 통해서 미등재 접미파생명사를 분석할 필요가 있다. 본 논문에서는 접미파생명사의 의미 분석의 일환으로 한국어 어휘의미망(U-WIN)을 이용한 동형이의어 접미사의 중의성 해소 방법을 제시한다. 형태 의미 주석 세종 말뭉치에서 동형이의어 접미사를 포함한 33,104개의 접미파생명사를 대상으로 실험하였다. 실험을 위해 먼저 동형이의어 접미사를 의미 태깅하였으며, 접미사 앞의 어근을 추출하여 U-WIN의 노드에 매핑시켰다. 또한 동형이의어 접미사와 결합되는 U-WIN 상의 노드들에 대해 거리 가중치를 부여하여 이를 동형이의어 접미사 중의성 해소에 사용하였다. 동형이의어 접미사 49종 중 세종말뭉치에 나타난 35개의 동형이의어 접미사를 대상으로 실험한 결과 91.01%의 정확률을 보였다.

• 한국조경학회:학술대회논문집
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• 한국조경학회 2007년도 Journal of Landscape Architecture in Asia Vol.3
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• pp.78-83
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• 2007

The colors have a close to our life and there are many color names derived from plants in Japan. This study aimed to analyze relationship people and plants and investigated what the images of colors derived from plants related to the color names. Surveys on color images of abstract and concrete were conducted with adults who lived in the metropolitan area and in urban areas. The subjects were surveyed about images of similar colors derived from plants(3 type of similar two colors; pink, green and yellow) and asked to select a pair of color names(momo or pink, midori or green, yamabuki or lemon) corresponding to the color. The subjects were simultaneously presented with two similar colors and asked to give their perceptions of each color against 13 polar opposite pairs of terms or phrases using a Semantic Differential Scale, and asked to select the number of the 16 items concerned with life such as clothes and food. With the pink colors, many subjects did not feel opposite abstract images between these two similar colors and felt the same concrete images such as 'cosmetics' and 'clothes', and these color names such as momo and pink are confused. With the green colors and the yellow colors, many subjects felt opposite abstract images between these two similar colors such as 'natural - artificial' and 'rural - urban' and different concrete images such as 'plants' and 'plastics', and these two similar colors are distinguished by the color names such as 'midori - green' and 'yamabuki - lemon'. The results revealed that there are two patterns in the relationship colors derived from plants, color images and color names. In the pattern which images of colors derived from plants are connected with artificial things irrelevant to plants, the color names corresponding to the two similar colors are confused. On the other hand, in the pattern which images of colors derived from plants are connected with plants and artificial things, the two similar colors are distinguished by their color names. So demographics influenced the images of color, younger subjects compared with older tend to obviously distinguish images of colors derived from plants, and there are images of color influenced by the environment as a child. In both patterns, images of colors derived from plants are influenced by artificial things and natural colors are limited among many people. These results indicate that there are a few opportunities to see colors of plants which are full of variety. These results suggest that it is necessary to recognize colors derived from plants in relation to plants and to educate regarding the nature of plants, therefore landscape architecture focused on colors of plants is required.

• Natural Product Sciences
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• 제23권2호
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• pp.146-150
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• 2017

Alnus sibirica (AS) geographically distributes in Korea, Japan, Northeast China and Russia. The bark of this plant had been used for antipyretic, expectorant, anti-phlogistic, antitussive, anti-asthmatic and as a health tea for alcoholism. Recently, we studied various biological activities of AS and the isolated diarylheptanoid. In present study, we conducted fermentation of AS (FAS) and isolated two diarylheptanoid (hirsutenone and muricarpone B). Moreover, we established the validation and contents determinations of the two compounds by HPLC on FAS.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2002년도 춘계학술발표대회 발표논문초록집
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• pp.18-18
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• 2002

This study was to investigate the effect of neurotrophic factors on neural cell differentiation in vitro derived from human embryonic stem (hES, MB03) cells. For neural progenitor cell formation derived from hES cells, we produced embryoid bodies (EB: for 5 days, without mitogen) from hES cells and then neurospheres (for 7 - 10 days, 20 ng/㎖ of bFGF added N2 medium) from EB. And then finally for the differentiation into mature neuron cells, neural progenitor cells were cultured in ⅰ) N2 medium (without bFGF), ⅱ) N2 supplemented with brain derived neurotrophic factor (BDNF, 5ng/㎖) or ⅲ) N2 supplemented with platelet derived growth factor-bb (PDGF-bb, 20ng/㎖) for 2 weeks. (omitted)