• 영재교육연구
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• 제22권2호
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• pp.353-370
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• 2012

최근 과학 영재 교육 대상자의 선발 제도로 관찰 추천제가 도입되었으며, 이는 잠재적 역량이 높은 과학 영재를 파악할 수 있는 신뢰롭고 타당한 선발 기준의 마련을 요구하고 있다. 이에 이 연구에서는 과학 영재의 내적 속성에 대한 변별을 도울 수 있는 역량을 탐색하고, 이를 사전화하였다. 검증된 선행 역량 사전/모델로부터 역량을 추출하고, 구조화된 설문과 초점 집단 면접을 통해 과학 영재의 역량을 규명하였다. 연구 결과, '목표 제시', '계획 수립', '정보 수집 및 분석', '문제 해결', '고차원적 사고', '전문 지식 및 자기 개발'의 6개 역량으로 구성된 인지적 역량군과 '자신감', '성취 지향성', '호기심'의 3개 역량으로 구성된 정의적 역량군을 도출하였다. 그리고 도출된 역량을 바탕으로 역량명과 역량에 대한 정의, 핵심 요소, 행동지표와 수준으로 구성된 역량 사전을 개발하였다. 이 연구 결과는 관찰 추천을 통한 잠재적인 과학 영재의 선발 기준에 대한 시사점을 제공할 것으로 기대된다.

• 천문학회보
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• 제44권1호
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• pp.39.2-39.2
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• 2019

Galaxy clusters are the largest gravitationally bound structures in the universe and located in the densest peak of the dark matter. They can constraint cosmologicals model from their dark matter halo distribution and they are good laboratories to study how galaxy evolution varies with their environment. Especially, studies of galaxy clusters at $z{\geq}1$ are important because (i) galaxy evolution at z >1 is still controversial (Elbaz et al. 2007; Faloon et al. 2013) and (ii) some studies show that mass of galaxy clusters at z>1 seems to be higher than expected value from the concordance LCDM cosmological model (Kang & Im 2009; Gonzales et al. 2012). In spite of their significance, there have not been many studies of galaxy clusters at $z{\geq}1$ because of the lack of wide and deep multi-wavelength data. We newly found galaxy cluster candidates at 0.2 < z < 1.4 and a LSS spanning over 100Mpc at z~0.9 in the ELAIS-N1 field which is one of the IMS (Infrared Medium-deep Survey; Im et al. 2019, in preparation) fields. Thanks to K-GMT science program, we performed spectroscopic follow-up observation for a z~1 galaxy cluster candidates with GMOS of Gemini North and for z~0.9 supercluster candidates with Hectospec of MMT in 2018A and confirmed the large scale structures. We present the newly discovered galaxy overdensities from the observation and the analysis result.

• 대기
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• 제29권4호
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• pp.451-461
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• 2019

Medium-range forecast is highly dependent on ensemble forecast data. However, operational weather forecasters have not enough time to digest all of detailed features revealed in ensemble forecast data. To utilize the ensemble data effectively in medium-range forecasting, representative weather patterns in East Asia in this study are defined. The k-means clustering analysis is applied for the objectivity of weather patterns. Input data used daily Mean Sea Level Pressure (MSLP) anomaly of the ECMWF ReAnalysis-Interim (ERA-Interim) during 1981~2010 (30 years) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Using the Explained Variance (EV), the optimal study area is defined by 20~60°N, 100~150°E. The number of clusters defined by Explained Cluster Variance (ECV) is thirty (k = 30). 30 representative weather patterns with their frequencies are summarized. Weather pattern #1 occurred all seasons, but it was about 56% in summer (June~September). The relatively rare occurrence of weather pattern (#30) occurred mainly in winter. Additionally, we investigate the relationship between weather patterns and extreme weather events such as heat wave, cold wave, and heavy rainfall as well as snowfall. The weather patterns associated with heavy rainfall exceeding 110 mm day^-1 were #1, #4, and #9 with days (%) of more than 10%. Heavy snowfall events exceeding 24 cm day^-1 mainly occurred in weather pattern #28 (4%) and #29 (6%). High and low temperature events (> 34℃ and < -14℃) were associated with weather pattern #1~4 (14~18%) and #28~29 (27~29%), respectively. These results suggest that the classification of various weather patterns will be used as a reference for grouping all ensemble forecast data, which will be useful for the scenario-based medium-range ensemble forecast in the future.

• 천문학회보
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• 제38권2호
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• pp.78.1-78.1
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• 2013

The hierarchical model of galaxy formation predicts that galaxy halos contain merger relics in the form of long stellar stream. Thus, tidal substructure of stars around globular clusters, such as tidal tails, could be an essential evidence of the merging scenario in the formation of the Galaxy. From April 2010 to December 2012, we obtained $45^{\prime}{\times}45^{\prime}$ wide-field JHKs near-infrared photometric imaging data for about 20 globular clusters in the Milky Way, and examined the stellar density distribution around globular clusters. Here, we introduce the preliminary results of stellar spatial distributions and radial surface density profiles of four globular clusters. In order to minimize the field star contamination and identify the cluster's member candidates stars, we used a statistical filtering algorithm and gave weights on the CMDs of globular clusters. In two-dimensional stellar density maps, we could found tidal stripping structures for some globular clusters. The orientation of tidal substructure seems to associate with the effects of dynamical interactions with the Galaxy and cluster's orbit. Indeed, the radial surface density profile accurately describes this stripping structures as a break in the slope of profile. The observational results could give us further observational evidence of merging scenario of the formation of the Galaxy.

• The Plant Pathology Journal
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• 제17권4호
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• pp.201-204
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• 2001

Ultrastructural observation was conducted for the cells of oriental cabbage, Brassica campestris ssp. pekinensis 'Chungawang', inoculated simultaneously with Turnip mosaic virus (TuMV-ACT2-4vq) and Ribgrass mosaic virus (RMV-Ca1dn2) which were known as major destructive viruses of oriental cabbage in Korea. In cells infected with RMV alone, the virus particles were located as bundle or scattering in cytosols and vacuoles, which were typical ultrastructures of tobamovirus. Vessels of xylem were compacted with RMV particles. The cells infected only with TuMV had the cluster of virus particles scarcely and the typical potyvirus inclusions of scrolls, pinwheels, tubes and laminated aggregates in cytosols. The TuMV particles were jammed lineally between tonoplasts. In double infection, the two unrelated viruses of TuMV-ACT2-4vq and RMV-CA1dn2 were located together in a cell, and typical properties of each virus were also observed. The potyvirus inclusions and the tobamovirus particles were mixed entirely in cytoplasm. The virus particles of RMV wre presented strikingly near and in the center of potyvirus inclusions. In vascular cells, the tobamovirus particles were located abundantly than those in single infection. The potyvirus inclusions were embedded in the cluster of RMV particles in phloem parenchyma cells and the vascular elements were degenerated severely.

• 응용통계연구
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• 제13권2호
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• pp.343-352
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• 2000

K-평균 군집화(K-means clustering)는 비계층적 군집화 방법이 하나로서 큰 자료에서 개체 군집화에 효율적인 것으로 알려져 있다. 그러나 종종 비교적 균일한 대군집의 일부를 소군집에 떼어주는 오류를 범하기도 한다. 이 연구에서는 그러한 현상을 정확히 인지하고 이에 대한 대책으로서 ‘이중 K-평균 군집화(double K-means clustering)’방법을 제시한다. 또한 실증적 사례에 새 방법론을 적용해보고 토의한다.

• 천문학회보
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• 제41권2호
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• pp.34.3-35
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• 2016

Ram pressure stripping of early-type galaxies has been largely neglected until now because of their gas poor nature. MUSE IFU observation vividly reveal the presence of star-forming blobs and ionised gas tails, around an early-type galaxy in Abell 2670. The galaxy was identified as a post-merger galaxy with disturbed faint features, in MOSAIC 2 deep optical images. The imaging also revealed a series of star-forming blobs, situated in the direction facing away from the cluster centre. Thanks to the revolutionary wide field-of-view of the MUSE, combined with 8.2-m VLT (UT-4) at Cerro Paranal, we could simultaneously obtain IFU spectra of the blobs, as well as the galaxy. The MUSE spectra clearly confirms that the star-forming blobs are associated with the early-type galaxy. Moreover, MUSE reveals long ionised-gas tails, emanating from the galaxy. The quantity of gas indicates a gas rich progenitor has merged with the early-type galaxy. However the direction of the tails and blobs, and the blob morphology, appears to indicate that strong ram-pressure stripping may have stripped out gas brought in by the merger. We will present kinematic structure of the whole system (the galaxy, star-forming blobs, and gas tails), as well as the star formation history of the system, supporting a scenario where a recent galaxy merger is subjected to cluster environmental mechanisms.

• 복식문화연구
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• 제13권1호
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• pp.161-173
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• 2005

The Main objective of this study was to investigate the relationship between shopping orientations and Knit wear Buying Behavior of female college students in the U.S. age 18 to 33. The questionnaires for this survey were developed to measure knitwear purchasing behavior, including sources of information about knitwear, evaluative criteria of knit wear product, attributes f store preference for knitwear, and shopping orientation. The questionnaire was administered to 119 female college students in the University of California. The data was analyzed by percentage, frequency, mean, factor analysis, Cluster Analysis and ANOVA, Duncan Multiple Range test. The female college students were classified into five subdivisions by cluster analysis; cautious shopping group, recreational shopping group, self-confident shopping group, shopping indifferent group, price conscious shopping group. In the case of fashion information sources of knit wear, significant differences were found according to shopping orientation subdivision in observation of others' and famous people's clothing, fashion shows, fashion articles in magazines, newspapers, and on the Internet, and shop displays. The evaluation criteria of knit wear product were significantly different depending on shopping orientation subdivision in fashionable, brand and store name, appropriate for different occasion, prestige. The store attributes of knitwear were significantly different depending on shopping orientation subdivision in product knowledge of sales personnel, store atmosphere, display of merchandise, layaway payment plan, price level, ease of parking and access, and new fashion.

• 복식문화연구
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• 제14권4호
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• pp.542-555
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• 2006

The main objective of this study was to investigate the relationship between benefits segmentation and knitwear purchasing behavior of college female students in the U.S. The questionnaires for this survey were developed to measure knitwear purchasing behavior and benefits segmentation. The questionnaire was administered to 119 female college students in the University of California. The data was analyzed by percentage, frequency, mean, factor analysis, Cluster Analysis and ANOVA, Duncan Multiple Range test. The female college students in the U.S. were classified into fourth subdivisions by the cluster analysis. In the case of fashion information sources of knit wear, significant differences were found according to benefits sought subdivision in observation of famous people's clothing, fashion articles in magazines and newspapers, TV advertisements, Newspaper advertisements, advice of salespeople, and Catalogs. The evaluation criteria of knit wear product of consumers were significantly different depending on benefits sought subdivision in design/style, quality of construction, fashionable, brand and store name, pleasing to others, prestige, and sexy. The store attributes of knitwear product of consumers were significantly different depending on benefits sought subdivision in friendliness of sales personnel, product knowledge of sales personnel, brand names, new fashion, and variety of products. The outlook for the industry of knitwear look to remain bright, there should be a continuous effort to research and invest in consumer satisfaction of knitwear.

• Applied Microscopy
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• 제18권1호
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• pp.77-91
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• 1988

Since the Urechis unicinctus-oocyte grows asynchronously in the body fluid, various oocytes in developmental stages can be prepared from each individual. The oocytes obtained from the coelomic fluid are then classified into five developmental stages according to the fine structural features. The earlier oocytes (${\sim}18{\mu}m$) form cluster and thereafter the oocytes grow singly without a distinct support of somatic cell, such as accessory cell or matrix cell. The yolk granules begin to appear already in the oocyte of cluster stage, however, the typical yolk was observed at the stage IV. Therefore, it was suggested that the yolk deposition is correlated with the coelomic fluid. The mature oocyte measured about $150{\mu}m$ produces the invagination not only on oolemma(indentation) but also on nuclear envelope. After the formation of the indentation, the mature ooytes are stored in storge sacs. The fine structural features were combined in aspect of structural concept of light microscopical observation.