• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.433-444
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• 2022

This study aimed to identify the change trajectories and clusters of Korean women's family values and depression levels, and the factors affecting depression, to use balanced panel data from the 1st to 7th rounds of the Korea Longitudinal Survey of Women and Families(KLSWF). The subjects of this study were 5,048 female panelists who participated in the KLSWF, and LSTM analysis was conducted using Python to divide the clusters of Korean women suffering from depression. In addition, descriptive statistical analysis, ANOVA, multinomial logistic regression analysis, and hierarchical regression analysis were analyzed using SPSS 23.0. Results, It was confirmed that women's depression increased with age, and family values had a significant impact on depression. It was found that the more open the marriage values of women in the married group, the higher the level of depression. The family values trajectory and depression level of the analyzed subjects were not a single pattern, but included four clusters. To prevent depression among Korean women and provide more concrete interventions, a humanities and sociological system that can identify depression groups should be prepared.

• Publications of The Korean Astronomical Society
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• v.28 no.3
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• pp.83-93
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• 2013

This is the second paper on a systematic search for variable stars in Cyg OB3 region. In this paper we present the observational properties of 46 variable stars found in the region. Among them, 27 are eclipsing binaries and others are semi-long periodic or slow irregular variables. Only 5 are known variables and the rest are newly discovered ones. We have obtained the period and amplitude of 20 eclipsing binaries using the phase fitting method, and present the light curves of 46 variable stars.

• Korean Journal of Medicinal Crop Science
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• v.25 no.2
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• pp.83-88
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• 2017

Background: This study was aimed to determine the optimal vine induction method for growing of Korean schisandra (Schisandra chinensis), by comparing plant growth and fruit yields between plants grown with either fence-type (U-type) or A-type induction. Methods and Results: Plants were transplanted on August 17, 2014, and the plant height, stem node number and weight were measured every two weeks, six times from June 17, 2016. The plant height, stem node number, and leaf length and width were higher with the A-type than with the U-type induction, by approximately 37.0%, 49.1%, 27.6%, and 12.7%, respectively. Although there was no significant difference between the photosynthesis rates of plants grown with the two vine induction method, the leaf area and leaf number per plant were higher in the plants grown with the A-type than the U-type, by approximately 23.7% and 46.0%, respectively. The number of green-color pixels, in a defined area of digital camera images of creeper leaves from the inducted vines, was significantly higher in the plants grown with the A-type than the U-type. The number of fruit clusters per plant was approximately 26 and 36, under the U-type and A-type, respectively. A two fold higher total fruit weight per plant was observed in the plants grown under the A-type (250 g/plant) than the U-type (120 g/plant). Conclusions: The A-type vine induction method is optimal for cultivation of Korean schisandra.

• Journal of The Korean Astronomical Society
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• v.48 no.6
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• pp.343-355
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• 2015

There is much observational evidence that active star formation is taking place in the Hii regions Sh 2-255 – 257. We present a photometric study of this star forming region (SFR) using imaging data obtained in passbands from the optical to the mid-infrared, in order to study the star formation process. A total of 218 members were identified using various selection criteria based on their observational properties. The SFR is reddened by at least E(B −V ) = 0.8 mag, and the reddening law toward the region is normal (R_V = 3.1). From the zero-age main sequence fitting method it is confirmed that the SFR is 2.1 ± 0.3 kpc from the Sun. The median age of the identified members is estimated to be about 1.3 Myr from a comparison of the Hertzsprung-Russell diagram (HRD) with stellar evolutionary models. The initial mass function (IMF) is derived from the HRD and the near-infrared (J, J −H) color-magnitude diagram. The slope of the IMF is about Γ = −1.6 ± 0.1, which is slightly steeper than that of the Salpeter/Kroupa IMF. It implies that low-mass star formation is dominant in the SFR. The sum of the masses of all the identified members provides the lower limit of the cluster mass (169M_⊙). We also analyzed the spectral energy distribution (SED) of pre-main sequence stars using the SED fitting tool of Robitaille et al., and confirm that there is a significant discrepancy between stellar mass and age obtained from two different methods based on the SED fitting tool and the HRD.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.6
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• pp.21-31
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• 2020

This study analyzed the spatio-temporal change pattern of greenhouse areas for Sangnam-myeon and Samrangjin-eup of Miryang-si in Gyeongnam, which is one of major greenhouse area. First, in order to overcome the lack of statistical data of the distribution of greenhouses, aerial and satellite images were interpreted from 1987 to 2018, and the spatial distribution of the greenhouse parcels which has continuously increased was mapped based on the digital cadastral map. Next, through the emerging hot spot tool in ArcGIS Desktop, the spatio-temporal change in transition from open-field to greenhouse cultivation was classified into 9 clusters. About 67.7% of the target area was categorized as a hot spot, and the pattern of New hot spot, which were recently converted to greenhouse parcels, covered about 34.1%. While, about 11.3% of parcels were expected to keep the existing open-field cultivation practice for a while. Overall, the greenhouse parcels have been densely developed along a river and were lately expanding even to the far neighbor. It implied that, in the future, the competition of water intake among farms would be more serious and the environmental responsibility in consideration of water quality as well as quantity would be getting strengthened due to increasing pollution loads and river intake.

• Current Photovoltaic Research
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• v.9 no.3
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• pp.84-95
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• 2021

The power conversion efficiency of Cu₂ZnSnSe₄ (CZTSe) solar cells depends on the absorber layer thickness; however, changes in the characteristics of the cells with varying absorber layer thickness are unclear. In this study, we investigated the changes in the characteristics of CZTSe solar cells for varying absorber layer thickness. Five absorber thicknesses were employed: CZTSe1 2.78 ㎛, CZTSe2 1.01 ㎛, CZTSe3 0.55 ㎛, CZTSe4 0.29 ㎛, and CZTSe5 0.15-0.23 ㎛. The efficiency of the CZTSe solar cells decreased as the absorber thickness decreased, resulting in power conversion efficiencies of 10.45% (CZTSe1), 8.67% (CZTSe2), 7.14% (CZTSe3), 3.44% (CZTSe4), and 1.54% (CZTSe5). As the thickness of the CZTSe absorber layer decreased, the electron-hole recombination at the grain boundaries and the absorber-back-contact interface increased. This caused an increase in the current loss, owing to light loss in the long-wavelength region. In addition, as the thickness of the CZTSe absorber layer decreased, more ZnSe was produced, and the resulting defects and defect clusters led to an open-circuit voltage loss.

• Journal of the Korean Society for information Management
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• v.37 no.2
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• pp.285-310
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• 2020

This paper analyzed SCOAP3 journals, which have been evaluated as successful open access models, to understand the characteristics of scholarly communication among domestic researchers in the field of high energy physics (HEP). As research methods, a quantitative analysis using statistics and a network analysis of authors' affiliated institutions and academic journals were conducted to understand collaboration and research activities of domestic researchers in the HEP field. The results of the study revealed that, among the 10 SCOAP3 journals in which Korean researchers participated, the proportion of articles in which Korean authors participated was 8.0% of the total. The proportion of papers with more than 1,000 co-authors per paper was 28.7% of the total. The results of this analysis proved that Korean researchers were actively collaborating in the HEP global network. From the results of the network analysis to understand the cooperative relationship centered on the affiliated organization, the cooperative network could be divided into three clusters: a cluster centered on S universities, a cluster centered on K research institutes that provided researchers a cooperative infrastructure with CERN, and a cluster centered on I research institute. Through the network analysis for research institutes and journals, it was found that JHEP, PRD, and PLB among academic journals were highly participating journals, and universities and researchers were also participating in the writing of open access papers. The results of this study can be used as a basic resource for understanding researchers and building a research information environment in libraries.

• Journal of Navigation and Port Research
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• v.27 no.3
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• pp.315-320
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• 2003

Since the beginning of open-door policy, China has been making rapid annual growth with an average 10% economic development. And due to this rapid growth, cargo volumes via ports have been also rapidly increased, and accordingly, current China government has intensively invested in port development. Further, this development project is significantly big scale, compared with those project which Korea and Japan have. Thus, China is beginning to threaten Korean ports, especially Busan port which try to be a hub port in Northeast Asia. For this reason, it has been very important issue for Korea and Busan port to investigate or analyze Chinese ports based on empirical data. Especially, although various studies related to Shanghai and Hong Kong have been conducted, the competitiveness of overall Chinese major ports has been little studied. In this paper, we analyzed competitiveness level of eight Chinese ports with capabilities as container terminal, based on reliable sources. From data analysis, eight Chinese ports were classified into four groups according to competitiveness level. Rankings among four clusters based on competitiveness level are cluster(Hone Kong), cluster C(Shanghai), cluster A(Qingdao, Tianjin, and Yantian) and cluster D(Dalian, Shekou, and Xiamen).

• Journal of the Korean Magnetics Society
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• v.19 no.5
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• pp.157-160
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• 2009

We have studied electronic structures and magnetic properties of one dimensional Ge chain nanoclusters using OpenMX method based on densty functional method. The calculation results show the strong antiferromagnetic interaction between Cr and Ge atoms. The magnetic interaction between Ge and Ge atoms are almost antiferromagnetic behaviors. The magnetic exchange interaction are occurred over the sevaral Ge atom layers. The magnitude of this interaction depends number of Ge atom.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.52.1-52.1
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• 2015

We have recently installed SQUEAN on the 82 inch telescope at the McDonald Observatory, USA. This instrument consists of an ANDOR CCD camera, a focal reducer, an electronic box, an auto guiding system and a new filter wheel which holds up to 20 filters. Currently the filter wheel is equipped with Johnson-Cousins BVRI filters, SDSS rizY and isiz filters, and 50nm medium band pass filters (M625(625nm), M675(675nm), M725(725nm), M775(775nm), M825(825nm), M875(875nm), M925s(925nm), M975(975nm), and M1025(1025nm)). Our medium band pass filter system is suitable with SED fitting. Filter transformation methods are essential for time-domain observations including transient objects, e.g., supernovae, variable stars, and solar system bodies. In this work, we develop a series of equations to convert the open clusters photometry data within these filter systems.