• Title/Summary/Keyword: open clusters

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Building Open API Ontologies based (ll Semantics for Smart Mashup (스마트 매쉬업을 위한 시맨틱 기반 Open API 온톨로지 구축 기법)

  • Lee, Yong Ju
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.7 no.3
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    • pp.11-23
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    • 2011
  • Recently, Open APIs are getting attention with the advent of Web 2.0. Open APIs are used to combine services and generate new services by Mashup. However, the growing number of available Open APIs raises a challenging issue how to locate the desired APIs. We automatically build ontologies from WSDL, WADL, HTML, and their underlying semantics. The key ingredient of our method is a technique that clusters input/output parameters in the collection of API methods into semantically meaningful concepts, and captures the hierarchical relationships between the terms contained in a parameter. These semantic ontologies allow search engines to support a similarity search for Open APIs based on various protocols such as SOAP, REST, JavaScript, and XML-RPC, and significantly improve the quality of APIs matching by the clustering and hierarchical relationships mechanism.

Domain Analysis on the Field of Open Access by Co-Word Analysis (동시출현단어 분석 기반 오픈 액세스 분야 지적구조에 관한 연구)

  • Seo, SunKyung;Chung, EunKyung
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.24 no.1
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    • pp.207-228
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    • 2013
  • Due to the advance of scholarly communication, the field of open access has been studied over the last decade. The purpose of this study is to analyze and demonstrate the field of open access via co-word analysis. The data set was collected from Web of Science citation database during the period from January 1998 to July 2012 using the Topic category. A total of 479 journal articles were retrieved and 8,643 noun keywords were extracted from the titles and abstracts. In order to achieve the purpose of this study, network analysis, clustering analysis and multidimensional scaling mapping were used to examine the domain and the sub-domains of open access field. 18 clusters in the network analysis are recognized and 4 clusters are shown in the map of multidimensional scaling. In addition, the centrality analysis in the weighted networks was used to explore the significant keywords in this field. The results of this study are expected to demonstrate and guide the intellectual structure and new approaches of open access field.

A Study on the Intellectual Structure of Domestic Open Access Area (국내 오픈액세스 분야의 지적구조 분석에 관한 연구)

  • Shin, Jueun;Kim, Seonghee
    • Journal of the Korean Society for Library and Information Science
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    • v.55 no.2
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    • pp.147-178
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    • 2021
  • In this study, co-word analysis was conducted to investigate the intellectual structure of the domestic open access area. Through KCI and RISS, 124 research articles related to open access in Korea were selected for analysis, and a total of 1,157 keywords were extracted from the title and abstract. Network analysis was performed on the selected keywords. As a result, 3 domains and 20 clusters were extracted, and intellectual relations among keywords from open access area were visualized through PFnet. The centrality analysis of weighted networks was used to identify the core keywords in this area. Finally, 5 clusters from cluster analysis were displayed on a multidimensional scaling map, and the intellectual structure was proposed based on the correlation between keywords. The results of this study can visually identify and can be used as basic data for predicting the future direction of open access research in Korea.

VARIABLE STARS IN THE REGION OF THE OPEN CLUSTER NGC 225 (산개성단 NGC 225 영역의 변광성)

  • JEON, YOUNG-BEOM;PARK, YOON-HO;LEE, SANG-MIN
    • Publications of The Korean Astronomical Society
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    • v.31 no.3
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    • pp.43-56
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    • 2016
  • Through time-series BV CCD photometry of the open cluster NGC 225 region, we have detected 30 variable stars including 22 new ones. They are five ${\delta}$ Scuti-type variable stars, a slowly pulsating B star, six eclipsing binary stars and 18 semi-long periodic or slow irregular variables, respectively. We have performed multiple-frequency analysis to determine pulsation frequencies of the ${\delta}$ Scuti-type stars and a slowly pulsating B star, using the discrete Fourier transform and linear least-square fitting methods. We also have derived the periods and amplitudes of 6 eclipsing binaries and a long-period variable star from the phase fitting method, and presented the light curves of all variable stars. A slowly pulsating B star is a member of NGC 225, but ${\delta}$ Scuti-type stars are not members from the positions in the color-magnitude diagram and the radial distancies from the center of the cluster. From Dias et al. (2014, A&A, 564, 79), only three variable stars including the slowly pulsating B star are members of clusters: two are in NGC 225 and one is in Stock 24. But a variable star in Stock 24 is not a member of the cluster because of its position of color-magnitude diagarm.

THE UNUSUAL STELLAR MASS FUNCTION OF STARBURST CLUSTERS

  • Dib, Sami
    • Journal of The Korean Astronomical Society
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    • v.40 no.4
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    • pp.157-160
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    • 2007
  • I present a model to explain the mass segregation and shallow mass functions observed in the central parts of starburst stellar clusters. The model assumes that the initial pre-stellar cores mass function resulting from the turbulent fragmentation of the proto-cluster cloud is significantly altered by the cores coalescence before they collapse to form stars. With appropriate, yet realistic parameters, this model based on the competition between cores coalescence and collapse reproduces the mass spectra of the well studied Arches cluster. Namely, the slopes at the intermediate and high mass ends, as well as the peculiar bump observed at $6M_{\bigodot}$. This coalescence-collapse process occurs on a short timescale of the order of the free fall time of the proto-cluster cloud (i.e., a few $10^4$ years), suggesting that mass segregation in Arches and similar clusters is primordial. The best fitting model implies the total mass of the Arches cluster is $1.45{\times}10^5M_{\bigodot}$, which is slightly higher than the often quoted, but completeness affected, observational value of a few $10^4M_{\bigodot}$. The model implies a star formation efficiency of ${\sim}30$ percent which implies that the Arches cluster is likely to a gravitationally bound system.

Rethinking Clusters : Towards a More Open and Evolutionary Approach (전통적 산업집적지의 변화과정과 경제적 성과)

  • Mackinnon, Danny
    • Journal of the Korean Academic Society of Industrial Cluster
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    • v.2 no.1
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    • pp.14-27
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    • 2008
  • Ousters have become a key focus of interest and analysis over the last decade or so, informed by the work of the Harvard business economist Michael Porter. Recent research, however, suggests that the classic Porterian conception of clusters needs to be rethought. In particular, the idea that clusters are geogaphically bounded and integrated units whose primary link to the outside world is through the export of goods and services to global markets is highly Questionable, if not untenable. Relational approaches to clusters and regional development stress the importance of the wider networks and 'pipelines' through which knowledge is exchanged with key partners and collaborators located outside of the particular cluster in question. Rather than the main external links being those between leading firms and global markets, firms may engage in a range of global relations with collaborators and suppliers. This paper address the challenge of rethinking clusters in the light of the recent emphasis on global networks md connections, drawing on experience from m old industrial region in Western Europe Scotland. In assessing cluster experiences and initiatives in Scotland, I examine the development of the oil and gas and electronics clusters. In conclusion, I suggest that cluster initiatives me only likely to generate lasting benefits for the region in question if there is significant local ownership md control of key industries and clusters.

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Mothers' Experiences of Caring for Visually Impaired Children (시각장애 아동을 위한 어머니의 돌봄 경험)

  • Oh, Sangeun
    • Child Health Nursing Research
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    • v.23 no.2
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    • pp.219-228
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    • 2017
  • Purpose: The purpose of this study was to understand and explore the essences of Korean mothers' experiences of caring for visually impaired children. Methods: Data were collected through individual in-depth interviews using open-ended questions. Five mothers of children with visual impairments participated in the interviews. Verbatim transcripts were analyzed using phenomenological analysis. Results: Analysis with Colaizzi's method showed two categories which included 14 themes in 4 theme clusters. The first category was 'surviving in the dark reality' included 2 theme clusters, of 'outcrying in the darkness' and 'enduring the darkness while caring for my child alone'. The second category was 'living as the light of maternal affection' including 2 theme clusters of 'preparing the light to shine in the darkness' and 'going through the darkness with the lights of love'. Conclusion: The findings from this study provide deep understanding of mothers' experiences of caring for visually impaired children. Based on the results of the study, health professionals can develop effective family nursing interventions to improve the quality of life for these families including the visually impaired children and their mothers.

UBV CCD PHOTOMETRY OF THE OPEN CLUSTER BERKELEY 2

  • ANN HONG BAE;PARK YOON HO;KANG YONG WOO
    • Journal of The Korean Astronomical Society
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    • v.31 no.1
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    • pp.39-50
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    • 1998
  • We present UBV CCD photometry of Be 2, previously unstudied open cluster. Our photometry covers a field of $3'.2\times3'.8$ of the sky centered on the cluster, which is slightly smaller than the cluster diameter estimated to be about 260'. We have determined the reddening, distance, age and metallicity of the cluster by fitting the Pad ova isochrones to the observed stellar distributions in color-magnitude diagram as well as main sequence fitting: $E(B-V)=0.8\pm0.05,\;(m-M)_o=13.6\pm0.1,\;log(t) =8.9\pm0.1$, and Z=0.008. The present photometry shows that Be 2 is a distant open cluster of intermediate age. that it is a distant intermediate-age open duster.

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KINEMATICAL FOCUS ON NGC 7086

  • Tadross, A.L.
    • Journal of The Korean Astronomical Society
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    • v.38 no.4
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    • pp.423-428
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    • 2005
  • The main physical parameters; the cluster center, distance, radius, age, reddening, and visual absorbtion; have been re-estimated and improved for the open cluster NGC 7086. The metal abundance, galactic distances, membership richness, luminosity function, mass function, and the total mass of NGC 7086 have been examined for the first time here using Monet et al. (2003) catalog.