• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.297-304
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• 2018

Coptis chinensis is used in oriental medicine for soothing, anti-inflammation, antimicrobial and antipyretic properties, and its main ingredient berberine is known to have strong antibacterial activity. In this study, we investigated the anti-microbial effect of hot water extract of Coptis chinensis (CW) on skin related microorganism and the airborne microbe, the antifungal effects of fungi, which are frequently detected in residential environments. CW showed antibacterial effect against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis, against the airborne microbe, which was collected in four different places. At the concentration of 100 mg/mL, the antimicrobial activity continued for 42 days, showed heat stability without change in the antimicrobial activity even after heat treatment. The MIC and MBC of CW against S. aureus was 0.03, 0.05 mg/mL, against S. epidermidis was 0.50, 0.75 mg/mL and against P. acne was 0.10, 0.15 mg/mL. As a result of measuring the MIC of four kinds of fungi with high detection frequency in the surrounding environment, Gliocladium virens was 65 mg/mL by determined as MIC which can inhibit one hundred percent of mycelial growth. The concentration 90 mg/mL was determined as MIC against Aureobasidium pullulans and 100 mg/mL against Penicilium pinophilum and Chaetomium globosum. CW was considered a safe extract that showed no irritation even in the ocular mucous membrane irritation evaluation test, a patch test. Therefore, these results suggest that Coptis chinensis has antimicrobial, antifungal and safety on human body and can be applied to the development of materials for cosmetic and residential environment industries.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.3
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• pp.115-120
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• 2016

$CeO_2$ is used as a co-catalyst with $TiO_2$ to improve the catalytic activity of $MnO_x$ and characterization of nano-sized powder is identified with de-NOx efficiency. A comparison between $MnO_x-CeO_2/TiO_2$ and single $CeO_2$ was conducted in terms of microstructural analysis to observe the behavior of $CeO_2$ in the ternary catalyst. The $MnO_x-CeO_2/TiO_2$ catalyst was synthesized by sol-gel method and the average particle size of the single $CeO_2$ is about $285{\mu}m$ due to the low thermal stability, whereas the particle size $MnO_x-CeO_2/TiO_2$ is about 130 nm. The strong interaction between Ce and Ti was identified through the EDS mapping by transmission electron microscopy (TEM). The improvement about 20 % of $de-NO_x$ efficiency is observed in the low-temperature ($150^{\circ}C{\sim}250^{\circ}C$) and vigorous oxygen exchange by well-dispersed $CeO_2$ is the reason of catalytic activity improvement.

• Journal of the Korean Vacuum Society
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• v.17 no.4
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• pp.359-364
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• 2008

We have investigated optical and structural properties of $Al_{0.3}Ga_{0.7}N$/GaN and $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ heterostructures (HSs) grown by metal-organic chemical vapor deposition, by means of Hall measurement, high-resolution X-ray diffraction, and temperature- and excitation power-dependent photoluminescence (PL) spectroscopy. A strong GaN band edge emission and its longitudinal optical phonon replicas were observed for all the samples. At 10 K, a 2DEG-related PL peak located at ${\sim}\;3.445\;eV$ was observed for $Al_{0.3}Ga_{0.7}N$/GaN HS, while two 2DEG peaks at ${\sim}\;3.42$ and ${\sim}\;3.445\;eV$ were observed for $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ HS due to the additional $Al_{0.15}Ga_{0.85}N$ layers. Moreover, the emission intensity of the 2DEG peak was higher in $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ HS than in $Al_{0.3}Ga_{0.7}N$/GaN HS probably due to an effective confinement of the photo-excited holes by the additional $Al_{0.15}Ga_{0.85}N$ layers. The 2DEG-related emission intensity decreased with increasing temperature and disappeared at temperatures above 150 K. To investigate the origin of the new 2DEG peaks, the energy-band structure for multiple AlGaN/GaN HSs were simulated and compared with the experimental data. As a result, the observed high- and low-energy peaks of 2DEG can be attributed to the spatially-separated 2DEG emissions formed at different AlGaN/GaN heterointerfaces.

• The Journal of Art Theory & Practice
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• no.5
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• pp.43-80
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• 2007

PASKYULA was formed in September, 1923 through the union of artists involved in two art groups: Kim Ki-Jin, Kim Bok-Jin, Yeon Hak-Nyeon who had previously participated in the ToWolHoi, and Park Young-Hi, Lee Sang-Hwa, An Seok-Ju, former members of the BaeckJo. After its founding, the PASKYULA artists had been searching for the social function of art to reform the harsh reality of Minjung and the nation with criticism toward society as well as art world. Their art theory for MinJung could grow relatively ease in relation to changing social and political conditions in the early 1920s. In August, 1925, PASKYULA organized the Korea Artista Proletaria Federatio with the YeomGunSa, and laid the groundwork for Proletariat art movement which was regularized in the late 1920s. From PASKYULA up to the early state of KAPF, the theory of art advocated by Kim Bok-Jin and An Seok-Ju could be summarized as "art for MinJung". At that time, widely ranging discourses on MinJung, however, was spawned in art theory, because many intellectuals-including artists and writers-begun to pay more attention to MinJung, who emerged as one of the social forces after the Samil Independent Movement. Sometimes, MinJung was construed as the target of enlightenment from a negative viewpoint. On the other hand, several intellectuals under the influence of individualism asserted that the discussion itself on MinJung exerted an evil influence on art. In contrast of these cases, the PASKYULA artists including Kim Bok-Jin, An Seok-Ju perceived that MinJung had the potential to change society, and regarded them as "a creator of genuine civilization and art". In the PASKYULA artist's writings, the concept of MinJung was often overlapped with the meaning of the Choson nation suffering under colony. Although their concept of MinJung was transformed gradually into the proletariat as they were under the strong influence of socialism, it did not change that they grasped the realities of the whole Choson Peninsula through the proletarian consciousness. In the early state of PASKYULA, the methodology for social function of art was presented in a twofold manner. First of all, Kim Bok-Jin emphasized on the necessity of education to improve MinJung's way of life through art, and it was embodied by the organization of ToWol Art Workshop and public lecture. Also, he championed "the popularization of art", which was one of methods to distribute art to MinJung. According to the PASKYULA artists, art should be not art for art' sake but art for MinJung. That was why they advocated the convergence of art and MinJung's life. Especially Kim Bok-Jin affirmed a link between art and industry because he considered industry the field inextricably linked with MinJung's life. In this context, his idea could be read as the generalization and equalization within the framework of possession. Kim Bok-Jin thought that the social ramifications of capitalism deprived MinJung of their right to enjoy art, and emphasized the artist' social role to return the right to them. That is, the even distribution of art was mainly discussed than the contents of art in the half of 1920s. By 1925, the contents of art itself became an issue in the PASKYULA art theory, and it was based in realism. Kim Bok-Jin and An Seok-Ju insisted that art should be reflection of real life. At that time, realism acquired the representation of MinJung and the nation's realities not realistic style. In fact, the various Western art styles including Futurism, Constructivism, Cubism etc. were exploited in the PASKYULA's visual images. Western art, target of criticism on theory, was selectively adopted in the works which were produced by Kim Bok-Jin and An Seok-Ju. Kim Bok-Jin's MoonYeUnDong cover design was conceived of as the example in which Western art was adopted with it's ideology under the influence of MAVO, while Western art shown in An Seok-Ju's illustrations served as a decorative function in many cases. Especially, An Seok-Ju attempted the various styles of Western art simultaneously, which may be seen as representing that PASKYULA did not have a firm ideology for their style. Also, it can be read as showing his hasty zeal to overcome Western art rapidly. The wish to establish "art for MinJung" as soon as possible was accompanied with the will to jump over the all steps of Western art though it was superficial. This aspiration of PASKYULA was expressed through the mass media, which had the potential for communicating to MinJung. At this point, there was a significant disparity between PASKYULA and another art groups in the first half of 1920s. However, the PASKYULA's method on the basis of the mass media could not but have a certain limitation because of the medium's properties. Nevertheless, PASKYULA' attempts may be considered to be valuable in sense that they expended the boundaries of Korean modern art into the commercial art questioning the matter of the distribution for art.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1447-1460
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• 2021

Urbanization increases the amount of impervious surface and artificial heat emission, resulting in urban heat island (UHI) effect. Local climate zones (LCZ) are a classification scheme for urban areas considering urban land cover characteristics and the geometry and structure of buildings, which can be used for analyzing urban heat island effect in detail. This study aimed to examine the UHI effect by urban structure in Suwon and Daegu using the LCZ scheme. First, the LCZ maps were generated using Landsat 8 images and convolutional neural network (CNN) deep learning over the two cities. Then, Surface UHI (SUHI), which indicates the land surface temperature (LST) difference between urban and rural areas, was analyzed by LCZ class. The results showed that the overall accuracies of the CNN models for LCZ classification were relatively high 87.9% and 81.7% for Suwon and Daegu, respectively. In general, Daegu had higher LST for all LCZ classes than Suwon. For both cities, LST tended to increase with increasing building density with relatively low building height. For both cities, the intensity of SUHI was very high in summer regardless of LCZ classes and was also relatively high except for a few classes in spring and fall. In winter the SUHI intensity was low, resulting in negative values for many LCZ classes. This implies that UHI is very strong in summer, and some urban areas often are colder than rural areas in winter. The research findings demonstrated the applicability of the LCZ data for SUHI analysis and can provide a basis for establishing timely strategies to respond urban on-going climate change over urban areas.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.4
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• pp.113-132
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• 2019

The degree of females' participation in corporate activity has been recently increased over the world and females' participation in economic activity may be new dynamic fuel for the Korean economy that falls into the vicious cycle of low growth. Start-up, therefore, has increasingly taken attention as an opportunity for females whose careers were interrupted to re-enter the labor market. The need for studies that examine factors influencing the decision of start-up is also increased along with the increase of the ratio of females' start-up. This study aims to verify effects of the women's characteristics(women discrimination, women's role conflict) and the human networks of females whose careers were interrupted, with the intention for entrepreneurial intention, which are mediated by personal attitudes and subjective norm suggested by Ajzen's Theory of Reasoned Action, based on an empirical research. The findings show that the human networks of females have an effect on attitudes toward start-up activity and subjective norm and the woman discrimination influence the personal attitudes. In contrast, the women's role conflict have no effect on both personal attitude toward start-up activity and subjective norm. This can be supposed as an outcome resulted from the subjects' low level of conflict caused by their sex roles, on their age distribution. The relation between subjective norm and entrepreneurial Intention seemed to be moderated by their perceived strong entrepreneurial supporting policy. Their attitudes toward start-up activity were found to have a mediating effect on the relation between the women discrimination, human networks and entrepreneurial Intention, while the subjective norm only mediated the relation between human networks and entrepreneurial Intention. Based on such results, this study attempts to suggest theoretical suggestions and the direction of various entrepreneurial supporting policy for the increase and the growth of start-up of females whose careers were interrupted, in Korea.

• Journal of Korea Water Resources Association
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• v.54 no.8
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• pp.577-587
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• 2021

Drought is generally considered to be a natural disaster caused by accumulated water shortages over a long period of time, taking months or years and slowly occurring. However, climate change has led to rapid changes in weather and environmental factors that directly affect agriculture, and extreme weather conditions have led to an increase in the frequency of rapidly developing droughts within weeks to months. This phenomenon is defined as 'Flash Drought', which is caused by an increase in surface temperature over a relatively short period of time and abnormally low and rapidly decreasing soil moisture. The detection and analysis of flash drought is essential because it has a significant impact on agriculture and natural ecosystems, and its impacts are associated with agricultural drought impacts. In South Korea, there is no clear definition of flash drought, so the purpose of this study is to identify and analyze its characteristics. In this study, flash drought detection condition was presented based on the satellite-derived drought index Evaporative Stress Index (ESI) from 2014 to 2018. ESI is used as an early warning indicator for rapidly-occurring flash drought a short period of time due to its similar relationship with reduced soil moisture content, lack of precipitation, increased evaporative demand due to low humidity, high temperature, and strong winds. The flash droughts were analyzed using hydrometeorological characteristics by comparing Standardized Precipitation Index (SPI), soil moisture, maximum temperature, relative humidity, wind speed, and precipitation. The correlation was analyzed based on the 8 weeks prior to the occurrence of the flash drought, and in most cases, a high correlation of 0.8(-0.8) or higher(lower) was expressed for ESI and SPI, soil moisture, and maximum temperature.

• Resources Recycling
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• v.30 no.4
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• pp.54-63
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• 2021

Vanadium and tungsten can be obtained by separating/recovering the leaching solution from a spent SCR DeNO_X catalyst using the soda roasting-water leaching process. Therefore, in this study, the adsorption/desorption mechanism of vanadium and tungsten in an ion-exchange column was investigated using Lewatit MonoPlus MP 600, a strong basic anion exchange resin. The operating conditions for the separation of vanadium and tungsten in the ion-exchange column was intended to present. By conducting a continuous adsorption experiment in a pH 8.5 solution, the adsorption capacity of vanadium and tungsten was found to be 44.75 and 64.92 mg/(g of resin), respectively, which showed that the adsorption capacity of tungsten was larger than that of vanadium because of the difference in ion charge. Vanadium has a higher affinity for MP 600 than tungsten. Consequently, as the vanadium-containing solution is eluted through the ion exchange resin onto which tungsten is adsorbed, the adsorbed tungsten is exchanged with vanadium and desorbed. A continuous experiment was performed with a solution of vanadium and tungsten prepared at the same concentration as the spent SCR DeNO_X catalyst leachate. The adsorption capacity of vanadium was found to be 48.72 mg/(g of resin) and 80% of the supplied vanadium was adsorbed; in contrast, almost no tungsten was adsorbed. Therefore, vanadium and tungsten were separated effectively. The ion exchange resin was treated with 2 M HCl at 15 mL/h, and 97.7% of the vanadium(99% purity) could be desorbed. After desorption, NH₄Cl was added to precipitate ammonium polyvanadate at 90℃ and recover 93% of the vanadium.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.273-280
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• 2021

GangAm Song Sungyong (1913~1999) was from Gimje, Jeollabuk-do. And he is a calligrapher from the last Confucian scholar of the 20th century and a writer of poetry, calligraphy, and painting. While wearing a topcoat and hanbok for the rest of his life, he approached the study, thought, and calligraphy art of Yoo Jae Song Kimyeon and Kojae Lee Byungeun from the perspective of 'GucheSinyong'. And he kept the philosophical subjectivity that tries to maintain character and a right mind. It was based on 'Guche', which is a faithful succession to the reverence of the old. When I was young, I practiced Mibul and Dong Kichang with Gu Yangsun as the center, and Hwang Jeonggyeon, Hanye, Oh Heejae, and Sojeon typefaces were grafted together during the national exhibition. Then, in 1965 (age 53), he moved to Jeonju, and learned several typefaces such as Chusa typeface on his own, creating a Gangam typeface without any obstacles. And he created 'Sinyong' with Windy Bamboo painting, which embodied strange and unconventional meanings. In addition, he re-established his identity by reexamining the fundamental spirit and natural aesthetics of calligraphy, and based on this, he greatly contributed to expanding the aesthetics of modern calligraphy and painting art by pursuing an aesthetic that explores novelty. In particular, Windy Bamboo painting has strong abstraction based on the principle of 'drawing the will'. And, in terms of discipline, the ethical aesthetic of Express Tao with pictures (畵以載道), which expresses the high level of elegance of observing small things in a big way, based on deep research on the logic of things and fulfilling human nature. By implementing it, Tao and Art become one. The Jeonbuk calligraphy group achieved the greatest prosperity in the Gangam era, and at the end of the 20th century, it entered a period of revival as it established itself as the central calligraphy group of Korean calligraphy.

• Journal of Intelligence and Information Systems
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• v.29 no.2
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• pp.57-84
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• 2023

With the development of information and communications technology (ICT) and big data technology, anyone can easily obtain and utilize vast amounts of data through the Internet. Therefore, the capability of selecting high-quality data from a large amount of information is becoming more important than the capability of just collecting them. This trend continues in academia; literature reviews, such as systematic and non-systematic reviews, have been conducted in various research fields to construct a healthy knowledge structure by selecting high-quality research from accumulated research materials. Meanwhile, after the COVID-19 pandemic, remote healthcare services, which have not been agreed upon, are allowed to a limited extent, and new healthcare services such as health recommender systems (HRS) equipped with artificial intelligence (AI) and big data technologies are in the spotlight. Although, in practice, HRS are considered one of the most important technologies to lead the future healthcare industry, literature review on HRS is relatively rare compared to other fields. In addition, although HRS are fields of convergence with a strong interdisciplinary nature, prior literature review studies have mainly applied either systematic or non-systematic review methods; hence, there are limitations in analyzing interactions or dynamic relationships with other research fields. Therefore, in this study, the overall network structure of HRS and surrounding research fields were identified using citation network analysis (CNA). Additionally, in this process, in order to address the problem that the latest papers are underestimated in their citation relationships, the GraphSAGE algorithm was applied. As a result, this study identified 'recommender system', 'wireless & IoT', 'computer vision', and 'text mining' as increasingly important research fields related to HRS research, and confirmed that 'personalization' and 'privacy' are emerging issues in HRS research. The study findings would provide both academic and practical insights into identifying the structure of the HRS research community, examining related research trends, and designing future HRS research directions.