• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.52.1-52.1
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• 2019

The Helioseismic and Magnetic Imager (HMI) is the instrument of Solar Dynamics Observatory (SDO) to study the magnetic field and oscillation at the solar surface. The HMI image is not enough to analyze very small magnetic features on solar surface since it has a spatial resolution of one arcsec. Super resolution is a technique that enhances the resolution of a low resolution image. In this study, we use a method for enhancing the solar image resolution using a Deep-learning model which generates a high resolution HMI image from a low resolution HMI image (4 by 4 binning). Deep learning networks try to find the hidden equation between low resolution image and high resolution image from given input and the corresponding output image. In this study, we trained a model based on a very deep residual channel attention networks (RCAN) with HMI images in 2014 and test it with HMI images in 2015. We find that the model achieves high quality results in view of both visual and measures: 31.40 peak signal-to-noise ratio(PSNR), Correlation Coefficient (0.96), Root mean square error (RMSE) is 0.004. This result is much better than the conventional bi-cubic interpolation. We will apply this model to full-resolution SDO/HMI and GST magnetograms.

• Asia-Pacific Journal of Business
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• v.11 no.4
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• pp.121-134
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• 2020

Purpose - The purpose of this study is to investigate consumer's satisfaction with the attractiveness, reliability, and professionalism that are characteristics of social influencers, and to investigate the impact of influencer characteristics on consumers' continuous use intention through satisfaction. Design/methodology/approach - A total of 293 questionnaires on independent samples were used for this study. Collected data were analyzed by SPSS 26.0 and AMOS 24.0 program and frequency analysis, reliability analysis, confirmatory factor analysis, correlation analysis and structural equation model analysis were performed. Findings - The findings demonstrated the followings: First, the attractiveness, reliability and professionalism of influencer had a positive effect on satisfaction. Second, the attractiveness and reliability of influencer had a positive effect on continuous use intention. However, professionalism did not have a significant impact. Third, user satisfaction with social media (channel of influence) had a positive effect on continuous use intention. Research implications or Originality - In doing so, this study was able to provide an in-depth understanding of the key characteristics of influencers and their roles, and contributed to ongoing research by providing suggestions for future studies.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.5
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• pp.824-836
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• 2020

This study investigated the effects of textile attachments on electroencephalogram using 20 persons (10 males and 10 females). Four types of attachment cushions were manufactured by changing the shell fabric (cotton and microfiber) and interlining (synthetic loose fiber and buckwheat). This was done using BIOS-S8 (BioBrain Inc., Korea), an 8-channel polygraph for multi-body signal measurement, to measure EEG. Data were analyzed using the SPSS 24.0 statistical program. EEG values were significantly activated according to gender, particularly when the subjects' eyes were open. For the male cases, 'RT', 'RAHB' values were highly activated and for the female cases, 'RA', 'RB', 'RG', 'RFA', 'RST', 'RLB', 'RMB', 'RST', 'RMT' values were highly activated. Examining the differences in EEG according to type of attachment indicated no significant difference in both sexes. However, in cases of females with their eyes closed, the 'RSA' index was quite different in the left occipital lobe (O1), and when their eyes were open, the 'RFA' in the right frontal lobe (F4) showed a significant difference. However, there was no obvious correlation between the activation of EEG and the subjective preference of textile attachments.

• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.116-121
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• 2020

In this study, a single-phase analysis of droplet slug with different contact angles was performed based on the visualization of experimental results. Droplet slug - flowing between gases in a hydrophobic mini channel - moves with a triple contact line without a gas liquid film on the wall. The results show that the rotational flow inside the droplet occurred; this was compared and verified with the results of two-phase analysis. The pressure field shows pressure rise at the front and rear ends. The effective length - the section that satisfies the laminar flow condition - became shorter as the droplet velocity increased. The Choi's correlation for the effective length agrees with this analysis results with a slight difference. This difference is judged as the difference in the contact angle of the slug model.

• Research in Community and Public Health Nursing
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• v.32 no.1
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• pp.12-23
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• 2021

Purpose: This study explored how and why young and middle-aged adults disclose depressive feelings to others. In particular, we investigated the role of social norms to see whether using mobile instant messaging (MIM) could lower the perceived barriers of emotional disclosure. Furthermore, the motivations of emotional disclosure via MIM were compared between young and middle-aged adults. Methods: A total of 255 Koreans (128 middle-aged people, 127 young adults) participated in an online survey. Pearson's correlation coefficients, paired t-tests, SPSS PROCESS macro, and exploratory factor analysis were used to examine the relationships among the key variables. Results: The perceived social norms were found to be a significant deterrent in disclosing depressive feelings to others. However, there was a significant interaction effect between generations and perceived social norms. Although young adults with low social norm awareness were more likely to disclose depressive feelings via MIM, emotional disclosure among middle-aged adults increased with higher levels of perceived social norms. Also, different motivations were observed. Conclusion: The results confirmed the significant effect of social norms as well as generational differences when using MIM as a channel of emotional disclosure.

• Journal of the Korean Society of Food Culture
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• v.37 no.4
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• pp.279-284
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• 2022

The purpose of this study is to analyze information about dietary information presented in the television broadcast media in order to determine the optimal communication method that will provide desirable information to the general public. To that end, stakeholders were recruited and trained before and during the study. Three airwaves broadcasters and four comprehensive programming channels were monitored for Three months. The results are as follows. In total 172 food and nutrition programs are reported on. As information from the monitored programs was investigated, results showed a frequency of 136 separate informative programs (79.1%) and 36 entertainment programs (20.9%). Second, the broadcasters included are KBS, MBC, SBS, while the channels are TV Chosun, JTBC, Channel A, and MBN. Third, 109 reports (63.3%) were about ingredients & cuisine, followed by 63 reports (36.7%) on health and diet. This research provides transitional knowledge regarding the correlation between dietary information and the media. Moreover, this research contributes to advocating public health by enhancing the quality from broadcast media about dietary information.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2524-2533
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• 2024

When analyzing containment thermal-hydraulics, computational fluid dynamics (CFD) is a powerful tool because multi-dimensional and local analysis is required for some accident scenarios. According to the previous study, neglecting steam bulk condensation in the CFD analysis leads to a significant error in boundary layer profiles. Validating the condensation model requires the experimental data near the condensing surface, however, available boundary layer data is quite limited. It is also important to confirm whether the heat and mass transfer analogy (HMTA) is still valid in the presence of bulk condensation. In this study, the boundary layer measurements on the vertical condensing surface in the presence of air were performed with the rectangular channel facility WINCS, which was designed to measure the velocity, temperature, and concentration boundary layers. We set the laminar flow condition and varied the Richardson number (1.0-23) and the steam volume fraction (0.35-0.57). The experimental results were used to validate CFD analysis and HMTA models. For the former, we implemented a bulk condensation model assuming local thermal equilibrium into the CFD code and confirmed its validity. For the latter, we validated the HMTA-based correlations, confirming that the mixed convection correlation reasonably predicted the sum of wall and bulk condensation rates.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2255-2265
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• 2013

This study presents the width function-based Clark model. To this end, rescaled width function with distinction between hillslope and channel velocity is used as time-area curve and then it is routed through linear storage within the framework of not finite difference scheme used in original Clark model but analytical expression of linear storage routing. There are three parameters focused in this study: storage coefficient, hillslope velocity and channel velocity. SCE-UA, one of the popular global optimization methods, is applied to estimate them. The shapes of resulting IUHs from this study are evaluated in terms of the three statistical moments of hydrologic response functions: mean, variance and the third moment about the center of IUH. The correlation coefficients to the three statistical moments simulated in this study against these of observed hydrographs were estimated at 0.995 for the mean, 0.993 for the variance and 0.983 for the third moment about the center of IUH. The shape of resulting IUHs from this study give rise to satisfactory simulation results in terms of the mean and variance. But the third moment about the center of IUH tend to be overestimated. Clark model proposed in this study is superior to the one only taking into account mean and variance of IUH with respect to skewness, peak discharge and peak time of runoff hydrograph. From this result it is confirmed that the method suggested in this study is useful tool to reflect the heterogeneity of drainage path and hydrodynamic parameters. The variation of statistical moments of IUH are mainly influenced by storage coefficient and in turn the effect of channel velocity is greater than the one of hillslope velocity. Therefore storage coefficient and channel velocity are the crucial factors in shaping the form of IUH and should be considered carefully to apply Clark model proposed in this study.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1631-1645
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• 2021

This research aims to provide the characteristics of the world's first active lidar sensor Atmospheric Laser Doppler Instrument (ALADIN) wind data and Geostationary Korea Multi Purpose Satellite 2A (GK2A) Atmospheric Motion Vector (AMV) data by comparing two wind data. As a result of comparing the data from September 2019 to August 1, 2020, The total number of collocated data for the AMV (using IR channel) and Mie channel ALADIN data is 177,681 which gives the Root Mean Square Error (RMSE) of 3.73 m/s and the correlation coefficient is 0.98. For a more detailed analysis, Comparison result considering altitude and latitude, the Normalized Root Mean Squared Error (NRMSE) is 0.2-0.3 at most latitude bands. However, the upper and middle layers in the lower latitudes and the lower layer in the southern hemispheric are larger than 0.4 at specific latitudes. These results are the same for the water vapor channel and the visible channel regardless of the season, and the channel-specific and seasonal characteristics do not appear prominently. Furthermore, as a result of analyzing the distribution of clouds in the latitude band with a large difference between the two wind data, Cirrus or cumulus clouds, which can lower the accuracy of height assignment of AMV, are distributed more than at other latitude bands. Accordingly, it is suggested that ALADIN wind data in the southern hemisphere and low latitude band, where the error of the AMV is large, can have a positive effect on the numerical forecast model.

• The Journal of Engineering Geology
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• v.32 no.3
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• pp.411-420
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• 2022

Recently, research using remote sensing has been active in various fields such as environment, science, and society. The results of research using remote sensing are not only numerical results, but also play an important role in solving and preventing social and scientific problems. The purpose of this thesis is to tell the correlation between the data provided and each data by using remote sensing technology for the tidal flat environment. The purpose of this study is to obtain high-resolution data using artificial satellites during remote sensing to find out information on tidal flat currents. Tidal flats created by erosion, sedimentation, low tide, and high tide contain information about the tidal flat slope and information about the ecosystem. Therefore, it can be considered as one of the very important studies to analyze the overall tidal flow channel. This paper creates a DEM (Digital Elevation Model) through TanDEM-X, and DEM is used as the most basic data to create a tidal channel. The research area is a tidal flat located in the middle of the west coast of Ganghwado tidal flat. By analyzing the tidal channel created, various information such as the slope direction of Ganghwado tidal flat and the shape of the tidal channel can be grasped. It is expected that the results of this study will increase the importance and necessity of using DEM data for tidal flat research in the future, and that high-quality results can be obtained.