• Journal of Internet Computing and Services
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• v.19 no.5
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• pp.89-96
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• 2018

In online communities, a large number of participants can exchange their opinion using replies without time and space restrictions. While the online space provides quick and free communication, it also easily triggers unnecessary quarrels and conflicts. The network established on the discussion participants is an important cue to analyze the confrontation and predict serious disputes. In this paper, we present a quantitative measure for polarity observed on the discussion network built from reply exchanges in online communities. The proposed method uses the comment exchange information to establish the user interaction network graph, computes its maximum spanning tree, and then performs vertex coloring to assign two colors to each node in order to divide the discussion participants into two subsets. Using the proportion of the comment exchanges across the partitioned user subsets, we compute the polarity measure, and quantify how discussion participants are bipolarized. Using experimental results, we demonstrate the effectiveness of our method for detecting polarization and show participants of a specific discussion subject tend to be divided into two camps when they debate.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.730-738
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• 1992

Filtration characteristics according to membrane materials were studied In the ultrafiltration of anaerobic digestion broth as a post treatment method. A series of resistances for different membranes were quantitatively assessed on the basis of the resistance-in-series model. Flux behavior observed with the digestion broth was irrelevant to initial water permeabilities of each membrane. The fluoro polymer membrane showed the most significant improvement of flux with increase of cross-flow velocity, which suggests that the cake layer formed on this membrane is more weakly attached to the membrane surface than those on the other membranes. Flux reduction during longtime running was attrib-used to the polarization layer resistance ($R_p$) as well as the fouling layer resistance($R_f$). Continuous increase of $R_p$ may reflect the variation in the characteristics of cake layers, which could result from size, shape, and structure changes due to lysis and growth of biomass. Hydrophilic cellulosic membrane had a much lower fouling tendency than hydrophobic polysulfone membrane. The depressurization method induced a small increase in flux of $5-10L/m^2/h$. During washing and cleaning, filtrability of each membrane was rapidly recovered within 15 minutes until a stationary value was reached.

• IMMUNE NETWORK
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• v.11 no.1
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• pp.79-94
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• 2011

Background: Dendritic cell (DC)-based vaccines are currently being evaluated as a novel strategy for tumor vaccination and immunotherapy. However, inducing long-term regression in established tumor-implanted mice is difficult. Here, we show that deoxypohophyllotoxin (DPT) induces maturation and activation of bone marrow-derived DCs via Toll-like receptor (TLR) 4 activation of MAPK and NF-${\kappa}B$. Methods: The phenotypic and functional maturation of DPT-treated DCs was assessed by flow cytometric analysis and cytokine production, respectively. DPT-treated DCs was also used for mixed leukocyte reaction to evaluate T cell-priming capacity and for tumor regression against melanoma. Results: DPT promoted the activation of $CD8^+$ T cells and the Th1 immune response by inducing IL-12 production in DCs. In a B16F10 melanoma-implanted mouse model, we demonstrated that DPT-treated DCs (DPT-DCs) enhance immune priming and regression of an established tumor in vivo. Furthermore, migration of DPT-DCs to the draining lymph nodes was induced via CCR7 upregulation. Mice that received DPT-DCs displayed enhanced antitumor therapeutic efficacy, which was associated with increased IFN-${\gamma}$ production and induction of cytotoxic T lymphocyte activity. Conclusion: These findings strongly suggest that the adjuvant effect of DPT in DC vaccination is associated with the polarization of T effector cells toward a Th1 phenotype and provides a potential therapeutic antitumor immunity.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.4
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• pp.191-200
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• 2017

As Korea experienced a Asian foreign exchange crisis in 1997 and a world financial crisis in 2008, the social structure of Korea has undergone many changes. The problem of polarization has become more serious, and the social class has become harder to move between strata. This problem has been accompanied by a growing sense of crisis that the power of social development can be lost along with the problem of population cliffs. Behind the crisis is a reflection of the fact that the growth-oriented economic policies and welfare policies implemented in various European countries can not solve the problem. As an alternative to this, the emergence of social enterprises is attracting attention. Social enterprises have the characteristic of seeking to generate economic profit in order to achieve the purpose of the public interest to provide jobs to the underprivileged. In recent years, the importance of social ventures to expand the scope of new social enterprises in innovative ways has increased. The social venture is a venture business in that it takes risks to develop new areas, not existing business areas, but it also has the character of a social enterprise to achieve the public interest. In other words, an innovative corporate model that provides a creative and challenging solution of social problems in the venture spirit. Although the interest and importance of social enterprises and social ventures are increasing, this academic research is still lacking. The purpose of this study is to introduce and analyze cases of successful social enterprises and social ventures in order to reflect these social interests and their importance and to fill the gap of previous studies. In addition, I hope that this study will stimulate interest and research on the start - up of social venture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.669-679
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• 2016

Architectural firms that would like to adopt the BIM are currently in an unfavorable position because of reduced orders, polarization of orders, and low price design. This study was conducted to evaluate plausible methods for supporting introduction of BIM into small sized firms. Before suggesting plans for support, we analyzed support projects and laws relating to support for small sized firms, after which we conducted a survey of small sized firms that support the project. The survey was completed by 242 architects and consisted of questions regarding the following aspects: current status and problems associated with BIM utilization, preference of certain policies for BIM introduction support, and reasonable level of support. After the survey, it was concluded that architectural firms are willing to use BIM and agree with the need for financial support for BIM program purchase and education, as well as to support BIM experts and fund low interest loans. In conclusion, it is proposed that support plans for small sized architectural firms in the areas of BIM introduction consulting, financial funding for the introductory process, provision of education and experts, order support, and promotions for accomplishment be provided.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.372-390
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• 2021

The objective of this study is to understand the current status of damage to Korean musical caused by the COVID-19, and also to seek for the coping measures and development direction in the post-Corona era. Thus, to understand the current status of damage, this study mainly researched the contents of NAVER TV musical performance transmitted for three years from March 2018 to February 2021 for analyzing the online performance and performance statistical data of Performing Arts Box Office Information System. As a result, this study could find a hypothesis and grounds to simultaneously verify and draw the positive and negative sides, pessimistic implications, and optimistic possibility. First, the performing arts would be multilaterally expanded after being divided into offline performance and online performance. Second, the utilization of online performance could narrow the gap(polarization) between capital area and non-capital area. Third, it is urgently needed to develop a win-win model for the establishment of a new musical market. Fourth, the performers' copyrights should be fairly protected. Fifth, the visualization requires the Korean-style support foundation and talent equipped with convergent thinking and knowledge. In such temporal changes from offline performance to online performance, there should be more sophisticated qualitative and quantitative growth in musical market.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.703-722
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• 2022

The concentration of local businesses in the capital region promotes a decrease in the local population and polarization between the capital region and non-capital regions. It affects the competitiveness of local industries and creates a vicious cycle throughout the local economy, society and culture. Therefore, this study classified the companies in the capital region and non-capital regions by group and examined the effect of the innovation capability factors of companies on the creation of business performance. We analyzed the effects of R&D capabilities, which are elements of innovation capability, and open innovation and convergence capabilities on business performance. Smart PLS 3.0 was used for analysis including direct and indirect mediating and moderating effects, multi-group analysis, and structural equation model analysis. As a result, R&D capability did not have a significant effect on business performance, but it has a positive influence towards business performance through convergence capability and open innovation. However, the effectiveness of open innovation in non-capital regions and convergence capabilities in capital region were not statistically significant. In particular, in terms of open innovation, as the difference between groups is statistically clear, follow-up measures are suggested especially in non-capital regions.

• Geophysics and Geophysical Exploration
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• v.24 no.4
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• pp.180-193
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• 2021

The complex resistivity method is an exploration technique that can obtain various characteristic information of underground media by measuring resistivity and phase in the frequency domain, and its utilization has recently increased. In this paper, a three-dimensional inversion algorithm for the CR data was developed to increase the utilization of this method. The Poisson equation, which can be applied when the electromagnetic coupling effect is ignored, was applied to the modeling, and the inversion algorithm was developed by modifying the existing algorithm by adopting comlex variables. In order to increase the stability of the inversion, a technique was introduced to automatically adjust the Lagrangian multiplier according to the ratio of the error vector and the model update vector. Furthermore, to compensate for the loss of data due to noisy phase data, a two-step inversion method that conducts inversion iterations using only resistivity data in the beginning and both of resistivity and phase data in the second half was developed. As a result of the experiment for the synthetic data, stable inversion results were obtained, and the validity to real data was also confirmed by applying the developed 3D inversion algorithm to the analysis of field data acquired near a hydrothermal mine.

• IMMUNE NETWORK
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• v.22 no.5
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• pp.40.1-40.24
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• 2022

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs, focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma. MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations, gene expression, and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma, including severe type 2 inflammation, airway fibrosis, and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF^-CD11c^-CD11b⁺ monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages, especially M2a and M2c. Furthermore, MSCs downregulated the excessive accumulation of Ly6c^- monocytes in the lungs. While an intravenous adoptive transfer of Ly6c^- monocytes promoted the infiltration of MoM and Th2 inflammation, that of MSC-exposed Ly6c^- monocytes did not. Ex vivo Ly6c^- MoMs upregulated M2-related genes, which were reduced by MSC treatment. Molecules secreted by Ly6c^- MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts, which were also suppressed by MSC treatment. In conclusion, intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c^- monocytes could be a therapeutic target for asthma management.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.515-530
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• 2021

This study is to estimate soil moisture (SM) using Sentinel-1A/B C-band SAR (synthetic aperture radar) images and Multiple Linear Regression Model(MLRM) in the Yongdam-Dam watershed of South Korea. Both the Sentinel-1A and -1B images (6 days interval and 10 m resolution) were collected for 5 years from 2015 to 2019. The geometric, radiometric, and noise corrections were performed using the SNAP (SentiNel Application Platform) software and converted to backscattering coefficient of VV and VH polarization. The in-situ SM data measured at 6 locations using TDR were used to validate the estimated SM results. The 5 days antecedent precipitation data were also collected to overcome the estimation difficulty for the vegetated area not reaching the ground. The MLRM modeling was performed using yearly data and seasonal data set, and correlation analysis was performed according to the number of the independent variable. The estimated SM was verified with observed SM using the coefficient of determination (R²) and the root mean square error (RMSE). As a result of SM modeling using only BSC in the grass area, R² was 0.13 and RMSE was 4.83%. When 5 days of antecedent precipitation data was used, R² was 0.37 and RMSE was 4.11%. With the use of dry days and seasonal regression equation to reflect the decrease pattern and seasonal variability of SM, the correlation increased significantly with R² of 0.69 and RMSE of 2.88%.