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Characteristic Analysis of Tropospheric Ozone Sensitivity from the Satellite-Based HCHO/NO2 Ratio in South Korea (위성 기반 HCHO/NO2 비율을 통한 국내 대류권 오존 민감도 특성 분석)

  • Jinah Jang;Yun Gon Lee ;Jeong-Ah Yu;Kyoung-Hee Sung;Sang-Min Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.563-576
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    • 2023
  • In this study nitrogen dioxide (NO2), formaldehyde (HCHO) from the Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI), OMI/ Microwave Limb Sounder (MLS) tropospheric column ozone (TCO), and Airkorea ground-based O3 data were analyzed to examine the photochemical reaction relationship between tropospheric ozone and its precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs). As a result of analyzing the trend of long-term changes from 2006 to 2020 using OMI satellite data, TCO showed an increasing trend, NO2 steadily decreased, and HCHO continued to increase in Northeast Asia. In addition, formaldehyde nitrogen dioxide ratio (FNR; HCHO/NO2 ratio), an indicator of ozone sensitivity, is gradually increasing, which means that the VOC-limited regime is decreasing. This study conducted a sensitivity analysis of ozone generation using TROPOMI FNR and ground-based ozone (O3) over the recent years (2019~2022) to identify the possible cause for the continuous increase of ozone in Korea. Similar to the previous studies, VOC-limited and transitional regimes appeared in megacities, and VOC-limited regimes also appeared in areas where major power plants were located. In VOC-limited regimes, in other words, areas where NOx is excessively saturated, the reduction in NOx emissions may have weakened the ozone titration and thus led to the increase of ozone. Therefore, VOC emissions should be reduced in the short term rather than NOx emissions to reduce ozone concentrations under the VOC-limited regime.

A Study on Tile from the Early Period of the Three Kingdoms Period Excavated in Bonghwang-dong (김해 봉황동 유적 일대 출토 삼국시대 초기 기와 검토)

  • YUN Sunkyung;KIM Jiyeon
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.40-52
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    • 2023
  • The basic purpose of building material called tiles is waterproofing and damp proofing, and they were restricted to use on important buildings to symbolize authority. This is especially true during the Three Kingdoms period, although unearthed examples are rare. Most of these tiles are found in ruins in the Silla and Baekje regions. Tiles were excavated from the Buwon-dong ruins that show the oldest manufacturing technique in the Gaya region to date, and tiles from the early Three Kingdoms period were recently excavated from the Gimhae Bonghwang-dong ruins, which is presumed to be the site of the royal palace of Geumgwan Gaya. These are important materials that show the appearance of tiles from the early days of Gimhae, the ancient capital of Geumgwan Gaya. The tiles excavated from the Bonghwang-dong ruins are reddish-yellow because a small amount of sand was mixed in the tile material and baked at a low temperature. The tiles are thin, no traces of fabric were identified, but traces of clay bands were identified. Tapping tool marks and traces of an anvil used in pottery production are clearly observed on the inside and outside, indicating that the tiles were made in the same way as earthenware manufacturing methods. If this is connected to the genealogy of the potters who made Gaya earthenware, it is estimated that tiles and earthenware were produced together as in the Songrim-ri ruins in Bulo-dong, Incheon, Songgok-dong ruins in Gyeongju, and Mulcheon-ri ruins. To date, tiles excavated from the Gimhae area have been identified only in places believed to be the Geumgwan Gaya City Wall (Royal Palace) in the Gimhae Basin. Considering what has been recorded so far and the geographical scenery, the Bonghwang-dong remains are the only city wall candidate site, and this is clearly revealed through the existence of the excavated tiles, which proves this. Considering that a small number of tiles were excavated during this time, it is estimated that the role of tiles as a luxury product with a symbolic meaning was greater than that of roofing materials, and there were strict restrictions and controls on its use.

A Study on the Bioactivity Exploration of the Collected Marine Microorganisms and Microalgaes in Korea (우리나라에서 확보한 해양미생물과 미세조류에 대한 기초생리활성 연구)

  • Seung Sub Bae;Yong Min Kwon;Dawoon Chung;Woon-Jong Yu;Kichul Cho;Eun-Seo Cho;Yoon-Hee Jung;Yun Gyeong Park;Hyemi Ahn;Dae-Sung Lee;Jin-Soo Park;Jaewook Lee;Dong-Chan Oh;Ki-Bong Oh;EunJi Cho;Sang-Ik Park;You-Jin Jeon;Hyo-Geun Lee;Keun-Yong Kim;Sang-Jip Nam;Hyukjae Choi;Cheol Ho Pan;Grace Choi
    • Journal of Marine Life Science
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    • v.8 no.2
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    • pp.136-149
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    • 2023
  • Basic bioactivities (antioxidant, anti-inflammatory, antibacterial, anticancer, antiviral) were investigated from 370 strains of marine bacteria, fungi, and microalgae obtained from various marine environmental regions in Korea, and the activity results were obtained at the collection site, isolation source, and species level was compared. In the case of marine bacteria, strains belonging to the generally useful genera Streptomyces and Bacillus were observed to have particularly strong efficacy and useful resources were mainly isolated from marine sediments. In the case of marine fungi and microalgae, results showing strong species-specific activity were confirmed, and results showing efficacy-specific activity were also obtained. Based on these results, it is a research result that can facilitate priority access as a strategic material for industrial revitalization and the establishment of a strategy to secure resources based on usefulness when conducting research on chemicals that are selectively effective against specific diseases or when conducting resource-based research. In addition, we believe that by using these results as material for sale through the Marine BioBank (MBB), academia and industry can use them to help accelerate the revitalization of the marine bio industry.

Community Structure of Natural Monument Forest (Forest of Japanese Torreyas in Pyeongdae-ri, Jeju and Subtropical Forest of Nabeup-ri, Jeju) in Jeju-do (제주도 천연기념물 수림지(제주 평대리 비자나무 숲과 제주 납읍리 난대림)의 군집구조)

  • Jeong Eun Lee;Yo Seob Hwang;Ho Jin Kim;Ju Heung Lee;Chung Weon Yun
    • Journal of Korean Society of Forest Science
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    • v.112 no.4
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    • pp.393-404
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    • 2023
  • The Natural Monument Forest (NMF) is a form of natural and cultural heritage that has symbolized the harmony between nature and culture in Korea for a long time. Recently, the NMF has deteriorated due to industrialization and reckless city expansion. Given this situation, it is necessary to preserve and manage the ecosystem of the NMF through preferential research regarding the forest community structure. Accordingly, this study sought to identify the community structure by analyzing the vegetation classification, stratum structure,and species diversity using vegetation data collected from the Forest of Japanese Torreyas in Pyeongdae-ri, Jeju and the Subtropical Forest of Nabeup-ri, Jeju. The results classified the forest vegetation as a Litsea japonica community group divided into two communities: a Torreya nuciferacommunity and a Quercus glauca community. The T. nuciferacommunity was subdivided into the Idesia polycarpa group and Dryopteris erythrosora group, while the Q. glauca community was subdivided into the Mercurialis leiocarpa group and Arachniodes aristata group. The T. nucifera species showed the highest level of importance in vegetation units 1 (Litsea japonicacommunity group-Torreya nucifera community-Idesia polycarpa group) and 2 (Litsea japonica community group-Torreya nucifera community-Dryopteris erythrosora group), whereas Q. glauca showed the highest level of importance in vegetation units 3 (Litsea japonica community group-Quercus glauca community-Mercurialis leiocarpa group) and 4 (Litsea japonica community group-Quercus glauca community-Arachniodes aristata group). In terms of the species diversity, vegetation units 1, 2, 3, and 4 had 2.866, 2.716, 2.222, and 2.326 species, respectively. These findings suggest that it is necessary to prepare a differentiated management plan for each vegetation unit.

A Review on Solution Plans for Preventing Environmental Contamination as the Trend Changes of Cryptocurrency (암호화폐의 트랜드 변화에 따른 환경오염 방지 해결방안에 대한 고찰)

  • Kim, Jeong-hun;Song, Sae-hee;Ko, Lim-hwan;Nam, Hak-hyun;Jang, Jae-hyuck;Jung, Hoi-yun;Choi, Hyuck-jae
    • Journal of Venture Innovation
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    • v.5 no.1
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    • pp.91-106
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    • 2022
  • Cryptocurrency, stood out the sharp cost rising of Bitcoin has been spotlighted by means of the solution for stagflation because it is decentralized with an existing currency differently. Especially getting into 4th industrial revolution, technologies using block chain and internet of things have been used in the many fields, and the power of influence is also widespread. Nevertheless like a remark of Elon Musk of Tesla CEO, the problems of environmental contamination for cryptocurrency have been pointed out continuously and the most representative of them is an enormous electric usage as the use of fossil fuels. Also the amount generated of carbon dioxide result in the acceleration of global warming mainly based on the climate changes of earth if the existing mining method is continued. On the other hand, review researches have been conducted restrictively as the connection with environmental contamination as the mining of cryptocurrency. In this study, it intended to review problems for environmental contamination as the diversification of ecological system of cryptocurrency concretely. Upon investigation existing prior documents on the putting recent data first, the mining of cryptocurrency has affected on the environmental contamination conflicting with carbon neutrality as increasement of the electric usage and electronic wastes. And POS method without the mining process appeared, but it had a demerit collapsing a decentralization and then we met turning point on appearing various environmental-friendly cryptocurrency. Finally the appearance of cryptocurrency using new renewable energy acted on the opportunity of the usage maximization of energy storage apparatus and the birth of national government intervention. Based on these results, we mention clearly that hereafter cryptocurrency will regress if not go abreast the value of currency as well as environmental approach.

Influence on Impulse Buying by Shopping Style according to Sales Promotion : Focusing on Consumers of Low-Cost Cosmetic Goods (소비자의 쇼핑성향이 충동구매행동에 미치는 영향 : 저가화장품의 판매촉진 전략의 매개효과를 중심으로)

  • Bok, Yun-gyoung;Kim, Jun-sung
    • Journal of Venture Innovation
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    • v.4 no.3
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    • pp.109-124
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    • 2021
  • This study intends to find out the influence of a consumer's shopping style on impulse buying mediated by sales promotion, based on low-cost cosmetic goods. For the study, pleasure, economical, and convenience shopping styles were set as the independent variables, and impulse buying was set as the dependent variable, and as the mediating variable between the two, sales promotions such as price discount event, free giveaway event, and visit-inducing activity were reviewed. Accordingly, the influence relation of shopping style, sales promotion, and impulse buying were reviewed with hierarchical regression analysis to examine the mutual influence relation. The data for this study employed a structured questionnaire, and 230 copies were collected against men and women in their 20s-30s, who are the main consumers of low-cost cosmetic goods, and 197 faithful responses were analyzed, and the major findings from the analysis results are as follows. First, pleasure-style consumers were found to have influenced impulse buying, while economical-style consumers were found to have a negative influence, and convenience-style was found to have no significant relation. Second, as for the examination of the mediating effect of sales promotion, price discount event, free giveaway event, and visit-inducing activity were found to have a partial mediating effect on the influence of pleasure shopping style on impulse buying, and did not fulfill the economical shopping style mediating effect condition. Also, as convenience shopping style was found to be insignificant towards impulse buying, it was excluded from the mediating effect. Such result is thought to be a useful elementary material for establishing a sales promotion strategy according to shopping styles through the analysis of styles of major consumers in order to increase the sales of businesses. The theoretical and pragmatic implications of such study results were discussed and the future study directions were suggested.

The Effect of Consumption Value and Consumers' Need for Cognition on Satisfaction through the Mediating Role of Trust in Online Shopping Websites (소비가치와 소비자의 인지욕구가 온라인 쇼핑 웹사이트에 대한 신뢰성을 매개로 만족도에 미치는 영향)

  • Lee, Yun-sun
    • Journal of Venture Innovation
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    • v.6 no.4
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    • pp.99-111
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    • 2023
  • This study aims to confirm that consumers' satisfaction with online shopping websites has changed to a phenomenon different from the past. In other words, in a situation where the use of e-commerce is expanding worldwide after the pandemic and various types of commerce such as mobile commerce and social commerce are formed, the consumer's information processing and decision-making process are meaningful in examining the behavior that has been changed based on the perceived motivation level of consumers by the new environment according to the consumption value and personal characteristics perceived by the consumer. In other words, the purpose of this study was to investigate the effect of consumption value and need for cognition on the satisfaction toward online websites as a mediating role in the trust of the website. As a result of testing Hypothesis 1, not only the hedonic value of the consumer for the website but also the utilitarian value had a positive influence on the satisfaction toward the website, and in particular, the utilitarian value showed a relatively greater influence than the hedonic value. However, the negative relationship between the need for cognition and satisfaction was found to be at a significant level under one-sided verification. In Hypothesis 2, only the utilitarian value among the consumption values of 2-1 showed a positive effect on satisfaction through a mediating role of trust. It was confirmed that the utilitarian value among the consumption values was an important factor in the satisfaction toward the website. The significance of this study is that, unlike previous research results, not only consumption value based on senses and emotions but also utilitarian value has a greater influence. Therefore, utilitarian value and need for cognition have a stronger influence on satisfaction if they play a mediating role based on the trust of the website used by consumers. These findings reflect the current market trend of online consumption, and they are helpful in the management and strategy of online websites based on consumer behavior understanding and major factors.

A Study on Factors Affecting ESG Management Intentions of Small and Medium Enterprises : Focusing on the Mediating Effect of Attitude and the Moderating Effect of Employees' Innovation Resistance (중소기업 ESG 경영 도입의도에 영향을 미치는 요인 : 태도의 매개효과 및 종업원 혁신저항성의 조절효과)

  • Lee, Yun-hyo;Park, Koung-hi;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.6 no.2
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    • pp.41-65
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    • 2023
  • This study was conducted to empirically analyse the factors that influence SMEs' intention to adopt ESG. For this purpose, we first derived the variables of usefulness of ESG and ease of adoption. In addition, we adopted CEO's will because of the importance of CEO's role in decision-making in SMEs. In addition, we added customer's request, government support, and credit evaluation reflection as institutional factors for ESG management. To examine the mediating role of attitudes and employees' innovation resistance in these relationships and how they affect ESG adoption, we set up a research model. These factors were used in the empirical analysis with 368 valid responses from the survey. Hierarchical regression analysis method using SPSS 24.0 was used for statistical analysis, and Process Macro 4.0 based on SPSS 24 was used for mediation and moderation effects. The results of the empirical analysis of this study showed that the usefulness of ESG adoption, ease of adoption, CEO's will, customer's request, government support, and credit evaluation reflection all had a positive and significant effect on the intention to adopt ESG management. In particular, among the variables affecting ESG adoption, CEO's will was found to be the most influential. Attitudes were also found to play a mediating role between the influencing factors and intention to adopt ESG management, as well as the mediating effect of employee' innovation resistance. The academic implications of this study include the identification and empirical testing of each of the influencing variables of ESG management adoption in the scarce literature on ESG in SMEs, and the prioritisation of the influence of these factors on adoption intention, which can be used to promote the adoption of ESG management. In terms of practical implications, it is important for SMEs to have a win-win relationship with large corporations, an ecosystem such as government support, in order to improve CEO awareness and motivate the CEO's will, and for smooth introduction of ESG management, it is necessary to find ways to reduce resistance through sufficient communication with organizational members to make them aware of the need.

Application of the Extract of Zanthoxylum piperitum DC to Manufacturing Eco-friendly Nosocomial Infection Control Protective Materials (초피의 항균 활성을 이용한 원내 감염 제어 친환경 방호 소재 개발)

  • Shin Young Park;Ki Yun Kim;Do Youn Jun;Sung Chul Kim;Hyo-Il Jung;Young Ho Kim
    • Journal of Life Science
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    • v.33 no.10
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    • pp.820-827
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    • 2023
  • Since COVID-19 began at the end of 2019, the wearing time of protective clothing used to prevent pathogenic bacteria and virus infection has increased, and the development of safe protective materials that are human-friendly and have antibacterial and antiviral functions has been required. In this study, we investigated the possibility of developing natural antibacterial protection materials using ethanol extract of the medicinal plant Zanthoxylum Piperitum DC. The antibacterial activity assay of the 80% ethanol extract of Z. piperitum DC leaves against various nosocomial infectious bacteria, using the disk diffusion method, showed that Staphylococcus aureus ATCC 25923, Klebsiella pneumoniae ATCC 13883, Salmonella typhimurium, and Aeromonas hydrophila are sensitive to the inhibitory action of the extract. The IC50 values of the ethanol extract against S. aureus, K. pneumoniae, P. vulgaris and A. hydrophila were about 0.59 mg/ml, 0.50 mg/ml, 1.06 mg/ml, and 0.06 mg/ml, respectively. To determine whether the ethanol extract of Z. piperitum DC leaves can be applied to the development of antibacterial protective fabric, the ethanol extract was tested using a protective fabric from the KM Health Care Corp. using the JIS L1902-Absorption method. As a result, the bacteriostatic and bactericidal activity values of S. aureus ATCC 25923 and K. pneumoniae ATCC 13883 appeared to be more than 2.0 when treated with the ethanol extract at a concentration of 1% (w/v). Together, these results suggest that Z. piperitum DC leaves can be applied to develop natural antibacterial functional protective fabrics.

Effects of Dietary Bacillus subtilis and Oregano Oil Supplementation on Performance, Egg Quality, and Intestinal Morphology in Late-Phase Laying Hens (산란말기 사료 내 Bacillus subtilis와 오레가노 오일 첨가가 산란계의 계란 생산성, 계란품질 및 장의 형태학적 특성에 미치는 영향)

  • Hyunsoo Kim;Hee-Jin Kim;Yeon-Seo Yun;Woo-Do Lee;Hyekyoung Shin;Jiseon Son;Eui-Chul Hong;Ik Soo Jeon;Hwan-Ku Kang
    • Korean Journal of Poultry Science
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    • v.50 no.4
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    • pp.311-323
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    • 2023
  • This study aimed to investigate the impact of Bacillus subtilis-based probiotics and oregano essential oil on the production performance, egg quality, and intestinal morphology of late-phase laying hens (69-weeks). A total of 150 laying hens of 69-week-old were randomly allotted into 6 treatment groups with 5 replicates of 5 birds in each replicate. Laying hens were divided into high (H) and average (A) egg production groups prior to the trial. The hens in each group were supplemented with Bacillus subtilis, or oregano essential oil: CON, a basal diet; BS, basal diet plus 3 × 108 CFU/kg feed Bacillus subtilis; OEO, basal diet plus 0.3 g/kg feed oregano essential oil. Egg performance, blood characteristics, egg quality, and intestinal morphology of the late-phase laying hens were evaluated. Both BS and OEO significantly enhanced (P<0.05) egg production compared to CON in high egg production. The blood characteristics indicated no significant differences based on the egg production and the supplementation of BS and OEO in the late-phase laying hens. The eggshell strength was significantly improved (P<0.05) in both OEO compared to both CON. A significantly decreased (P<0.05) the villus height to crypt depth ratio (VH/CD) in the ileum compared to H, and in the treatment groups supplemented with BS and OEO, VH/CD showed a significant increase (P<0.05) compared to both CON. These results suggest that the supplementation of Bacillus subtilis and oregano essential oil in the diet of late-phase laying hens could serve as a potential strategy to enhance egg production, egg quality, and gut health.