• 한국수학교육학회지시리즈A:수학교육
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• 제60권3호
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• pp.265-279
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• 2021

본 연구에서는 초등수학 교과서의 자료와 가능성 영역에 제시된 발문을 학년군별로 비교 분석하여 발문의 특성을 파악하였다. 연구 결과 학년군별로 교과서에 제시된 발문의 유형 및 기능별 출현 비율이 서로 다르게 나타났으며, 이는 학년군별 학습 내용 및 학년군의 특성과 관련이 있는 것으로 보인다. 또한 발문의 기능은 발문의 유형과 관련이 있음을 알 수 있다. 본 연구의 결과는 초등수학의 자료와 가능성 영역 지도 시 발문 사용에 대한 교수·학습상의 기초를 제공하여 발전적인 방향으로 통계교육이 이루어지는데 기여할 수 있을 것이다.

• 천문학회지
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• 제38권3호
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• pp.345-355
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• 2005

We present a photometric study of the star cluster system in the merging galaxy NGC 1487, based on the BI photometry obtained from the F450W and F814W images in the HST /WFPC2 archive data. We have found about 560 star cluster candidates in NGC 1487, using the morphological parameters of the objects. We have investigated several photometric characteristics of the clusters: color-magnitude diagrams (CMDs), color distribution, spatial distribution, age, size and luminosity function. The CMD of the bright clusters with 18.5 < B < 24 mag in NGC 1487 shows three major populations of clusters: a blue cluster population with $(B-I){\le}0.45$, an intermediate-color cluster population with $0.45<(B-I){\le}1.55$, and a red cluster population with (B - I) > 1.55. The intermediate-color population is the most dominant among the three populations. The brightest clusters in the blue and intermediate- color populations are as bright as $B{\approx}18mag$ ($M_B{\approx}-12mag$), which are three magnitudes brighter than those in the red population. The blue and intermediate-color clusters are strongly concentrated on the bright condensations, while the red clusters are relatively more scattered over the galaxy. The CMD of these clusters is found to be remarkably similar to that of the clusters in the famous interacting system M51. From this we suggest that the intermediate-color clusters were, probably, formed during the merging process which occurred about 500 Myrs ago.

• 천문학회지
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• 제37권5호
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• pp.307-313
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• 2004

Clusters of galaxies are believed to constitute a population of astrophysical objects potentially able to emit electromagnetic radiation up to gamma-ray energies. Evidence of the existence of non-thermal radiation processes in galaxy clusters is indicated from observations of diffuse radio halos, hard X-ray and EUV excess emission. The presence of cosmic ray acceleration processes and its confinement on cosmological timescales nearly inevitably yields in predicting energetic gamma-ray emission, either directly deduceably from a cluster's multifreqency emission characteristics or indirectly during large-scale cosmological structure formation processes. This theoretical reasoning suggests several scenarios to actually detect galaxy clusters at gamma-ray wavelengths: Either resolved as individual sources of point-like or extended gamma-ray emission, by investigating spatial-statistical correlations with unidentified gamma-ray sources or, if unresolved, through their contribution to the extragalactic diffuse gamma-ray background. In the following I review the situation concerning the proposed relation between galaxy clusters and high-energy gamma-ray observations from an observational point-of-view.

• 한국의류학회지
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• 제36권3호
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• pp.360-370
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• 2012

This study investigates the interaction effects of mechanical property-based clusters and colorimetric tones on the subjective touch and color sensation of fabrics when sight and touch were simultaneously provided to humans. Each of six different silk fabrics was colored by digital textile printing to have three tones (pale, vivid, and grayish) and its mechanical properties were measured by a Kawabata Evaluation System (KES). Touch and color sensation were identified to be primarily influenced by mechanical property-based clusters and tones, respectively. In touch, 'smooth', 'warm', 'heavy', and 'soft' were found to be affected by interactive effects of mechanical property-based clusters and colorimetric tone so that the pale tone tended to make differences smaller among the clusters for the touch sensation, while the grayish tone seemed to contribute to larger differences of 'heavy'. However, an interaction effect was not found in the color sensation with touch even though the color sensation was also influenced by mechanical property-based clusters.

• 한국의류학회지
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• 제34권10호
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• pp.1611-1620
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• 2010

This research compares the difference of each preference segments' subjective hands and sensibilities in order to analyze the correlations among preference, subjective hands, and sensibilities. Preference segments were classified into wool, acrylic, and long stitch length-preferred clusters in previous research. To evaluate the subjective hands and sensibilities of knit fabrics, the 20's and 30's women rated twelve knit fabrics by touching, using a questionnaire with a seven-point semantic differential scale. These twelve knit fabrics were differentiated by controlling the mixture ratio and stitch length using a computer-controlled automatic flat knit machine. The difference of each preference segments' subjective hands and sensibilities was determined using the conjoint analysis. The clusters perceived the subjective hands and sensibilities differently according to preferred constituent characteristics. There was no correlation between surface unevenness and preference in wool-preferred cluster, while there were negative correlations in other clusters. The acrylic-preferred cluster had a preference in coolness compared to other clusters; in addition, the long stitch-preferred cluster preferred flexibility/bulkiness and extensibility than the others. All clusters preferred modem and natural sensibilities that were caused by different constituent characteristics of knit fabrics.

• 복식문화연구
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• 제13권1호
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• pp.18-33
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• 2005

The purposes of this study were to investigate the difference of the SCM activities in the general characteristics of fashion enterprises and to inquire out the general characteristics affecting the introduction of SCM. The characteristics of apparel manufactures were also compared through the cluster analysis of the SCM activity levels of apparel manufactures. Through questionnaire survey, a total af 214 data - 123 from 64 apparel manufacturers, 46 from 40 fabric suppliers and 45 from 4 retailers - were used for analysis. The analysis on the relation between the SCM activity levels and the general characteristics of fashion enterprises showed that the SCM activities were affected by product assortment pattern and SCM introduction level for fabric suppliers, production method, product assortment pattern, business type and SCM introduction level for apparel manufacturers, and SCM introduction level for retailers. The cluster characteristics related to the SCM activity levels of apparel manufacturers showed that the clusters with higher level were tending to doing business internationally and trying to manufacture in a small lot in variety. The higher level clusters also revealed relatively low in the occupation ratio of fashion goods and high in quick response ratio compared to the lower level clusters.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.303-303
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• 2022

The purpose of this study was to evaluate agronomic characteristics and identify the useful traits to utilize the wheat genetic resources for breeding programs by understanding the phenotypic variation among germplasm through multivariate analysis. In this study, a total of 394 wheat accessions were characterized for 15 agronomic traits using the National Agrobiodiversity Center (NAC) descriptor list, of which 31 accessions from 6 species and 363 unidentified accession (Triticum spp.) available at the NAC, Rural Development Administration (RDA), Korea. Growth characteristics such as leaf width, culm length, spike length, spikelet length, solid stemmed, days to heading, days to maturity, grain-filing period, and also seed characteristics such as width, height, area, perimeter, circle, solidity, and germination percent were studied. Among the 15 agronomic characteristics, the germination percent showed the smallest variation between resources (CV = 0.4%), and the spikelet length (CV = 66.5%) showed the highest variation. A strong positive correlation was found between seed traits such as seed height and seed area (r = 0.90), seed height and seed perimeter (r = 0.87) and seed length and width (r = 0.80). Principal component analysis (PCA) was conducted and the first five principal components comprised 76.7% of the total variance. Among the first five PCs, PCI accounted for 28.5% and PC2 for 20.0%. Wheat resources (394) were classified into four clusters based on cluster analysis, consisting of 215 resources(I), 117 resources(II), 48 resources(III), and 14 resources(IV). Among the clusters, the resources belonging to Cluster III showed the lowest seed width, height, area, and perimeter characteristics compared to other clusters. The wheat resources belonging to cluster IV had small seed width and low germination percent, but took longer to form heads and mature than resources in other clusters. These results will serve as the basis for further genetic diversity studies, and important agronomic characteristics will be used for improving wheat, including developing high-yielding and resistant varieties to biotic and abiotic stresses via breeding programs.

• 한국경제지리학회지
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• 제25권4호
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• pp.514-530
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• 2022

세계적으로 산업 경쟁력을 높이기 위해 산업 클러스터의 육성이 다양하게 추진되고 있다. 이 연구는 세계적 경쟁 속에서도 안정적 산업 성장을 보여주고 있는 독일에서 지역기업의 경쟁력을 강화하고 연계산업의 지속적인 발전을 이끌고 있는 바이에른주의 지역산업 클러스터의 형성과 발전과정을 살펴보고자 한다. 이를 위해, 이 연구는 먼저 지역산업 클러스터를 이론적으로 개관하고, 뒤이어 독일 바이에른주를 사례로 지역산업 클러스터 정책의 전개 과정과 특성을 살펴보고자 한다. 특히, 이 연구는 바이에른주의 지역산업 클러스터의 형성과 구성 체계를 파악하고자 한다. 이러한 분석 결과를 바탕으로 하여, 이 연구는 독일 바이에른주의 지역산업 클러스터의 주요 특성과 성공 요인을 고찰하고자 한다.

• 천문학회보
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• 제44권2호
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• pp.40.1-40.1
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• 2019

We report progress on identifying cosmic voids using cluster halos as the antipode. According to the standard scenario of structure formation, clusters are expected to form at peaks of the initial density field, whereas cosmic voids form at troughs. Then, a cluster would be a void if the sign of the initial density fluctuation of the universe were inverted. To study the relevance of anti-structures of clusters to cosmic voids, we use a pair of simulations whose initial density fields are sign inverted versions to each other. By examining the spatial distribution and environment of the particles in inverted simulation, which are the member particles of clusters in the other simulation, we discuss the characteristics of the antipode structures of clusters including their size, density, internal structure, and redshift evolution as well.

• 중환자간호학회지
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• 제12권1호
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• pp.1-12
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• 2019

Purpose : It is widely accepted that addressing multiple symptoms together is the preferred approach in assessment and intervention and results in reduced negative patient outcomes. Yet, there are few studies examining symptom clusters and their impacts on quality of life longitudinally in patients after heart valve surgery. Methods: A total of 101 patients were recruited from a tertiary hospital and were administered questionnaires (at 3, 6, and 10 weeks after the surgery) assessing participants' characteristics, cardiac symptoms, and quality of life. Factor analysis was used to identify symptom clusters. Hierarchical multiple linear regression was used to predict quality of life. Results: Participants were predominantly 70-years old or more with a mean age of 64.34. The two symptom clusters at 3 weeks after the surgery with education, gender, and occupation accounted for 76.3% of variance in quality of life. Conclusion: Symptom clusters containing various physical and psychological symptoms in patients after the surgery affected quality of life, and the relationship was significant at 3 weeks after the surgery. Because symptom clusters were identified in all three recovery periods, nurses need to acknowledge these clusters, rather than each symptom separately, and to utilize these in providing care and education and in promoting quality of life in these patients.