• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.587-597
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• 2023

We evaluated the eutrophication of Saemangeum Lake, which causes abnormal growth of algae, using the Carlson index. Eutrophication characteristics of Saemangeum Lake were analyzed. For the study, water quality surveys were conducted at 7 stations in Saemangeum Lake every month in 2021. The concentration of Chl.a was slightly higher in the Mankyeong water system in winter, and slightly higher in the Dongjin water system in spring and summer, but overall, except for some periods, the concentration was similar to or lower than the lake water quality environmental standard of class 3. COD showed water quality similar to or above the lake quality environmental standard of grade 4 in both the Mankyeong and Dongjin water systems in the summer and Autumn. TOC concentrations were within lake water quality standard 3 at all sites. Total phosphorus concentrations exceeded the lake water quality standard of Class 4 and were higher in January and August after rainfall. In the correlation analysis between water quality factors, the correlation of organic matter, total phosphorus, and total nitrogen to salinity was relatively high. This reflected the water quality characteristics of freshwater, brackish water, and seawater areas due to seawater inflow through the drainage gate and freshwater inflow through upstream rivers. According to the characteristics of eutrophication fluctuations in Saemangeum Lake by trophic state index, the indices of Chl.a, SD, and TN showed water quality in the early stage of eutrophication, while the TP index showed a severe eutrophication state. The magnitude of the eutrophication index among water quality components was TSI(TP) > TSI(TN) > TSI(SD) > TSI(CHL) in all water systems. Quadrant analysis of the deviation of TSI(CHL) from TSI(TP) and TSI(SD) on a two-dimensional plane showed that there was no limiting effect of total phosphorus on algal growth in all water systems. In addition, the factors af ecting light attenuation appeared to be dominated by small particulate matter from outside sources.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.142-150
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• 2023

As global warming continues, the time of invasion of Spodoptera frugiperda has been advanced and the inflow rate has been increasing, leading to great increases in damage to crops. In this study, in order to minimize crop damage caused by S. frugiperda, the control period was set for corn fields through control thresholds, and the control effects according to the chemical spraying methods were investigated in forage corn filed. Even under the condition of 4% injury level during the corn silking stage, the damage rate of ear was 70%, showing an aspect of extensive damage. The economic injury level of S. frugiperda second instar larvae was shown to be 0.7 larvae per stalk, and the control threshold level was shown to be 0.6 larvae. The income was calculated by applying the corn wholesale unit price, and according to the result, even under the condition of injury level of 4%, there was a loss of KRW 895,221/10a, and the higher the injury level, the greater the decrease in income. To control S. frugiperda, the insecticidal effects of 10 single formulations registered for S. frugiperda were tested, and according to the results, four types(emamectin benzoate, chlorantraniliprole, indoxacarb, and spinetoram) showed high insecticidal activity not lower than 93.3%, and three types (chloran- traniliprole, spinetoram, and indoxacarb) were considered to be effective in controlling S. frugiperda as they showed high residual effects through insecticidal effect persistence tests. Therefore, conventional control and aerial control were conducted twice at 7-day intervals with indoxacarb SC and chlorantraniliprol WP, which show high activity against S. frugiperda, respectively, prior to the silking of forage corn. As a result, conventional control showed higher control values, 46.3%p in the case of indoxacarb SC and 21.7%p in the case of chlorantraniliprol WP, than aerial control through the primary control. In the secondary control too, higher control values of 26.7%p in the case of indoxacarb SC and 40.4%p in the case of chlorantraniliprol WP were found in conventional control than in aerial control. Therefore, it is considered necessary to prepare measures to improve the control effects in the recent situation where alternative methods for manpower control are widely used.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.361-372
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• 2023

Organotin pesticide is used as an acaricide in agriculture and may contaminate livestock products. This study aims to develop a rapid and straightforward analytical method for detecting organotin pesticides, specifically azocyclotin, cyhexatin, and fenbutatin oxide, in various livestock products, including beef, pork, chicken, egg, and milk, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The extraction process involved the use of 1% acetic acid in a mixture of acetonitrile and ethyl acetate (1:1). This was followed by the addition of anhydrous magnesium sulfate (MgSO₄) and anhydrous sodium chloride. The extracts were subsequently purified using octadecyl (C₁₈) and primary secondary amine (PSA), after which the supernatant was evaporated. Organotin pesticide recovery ranged from 75.7 to 115.3%, with a coefficient of variation (CV) below 25.3%. The results meet the criteria range of the Codex guidelines (CODEX CAC/GL 40). The analytical method in this study will be invaluable for the analysis of organotin pesticides in livestock products.

• Korean Journal of Culture and Social Issue
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• v.15 no.2
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• pp.291-318
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• 2009

The purpose of this study was to find out the impact of psycho-social factors (social relationship and personal) as well as illness history and economic status on physical health and subjective well-being among the retired Koreans elderly. Data were collected from 1,315 elders (mean age = 72.70yrs) residing in Seoul and Chuncheon regional area via interviews(Time 1), and them were re-interviewed two year later(Time 2). Multiple regression analyses indicated that the retired elders' illness history, economic status, marital satisfaction, fulfillment of self-esteem need, drinking behavior, positive affectivity, negative affectivity and physical health to predict their subjective well-being at Time 1(R²=.705). The retired elders' economic status, marital satisfaction, positive affectivity, negative affectivity and physical health to predict their subjective well-being at Time 2(R²=.418). The retired elders' illness history, economic status, expectations for one's offspring, drinking behavior and subjective well-being to predict their physical health at Time 1(R²=.364). And the retired elders' illness history, economic status, marital satisfaction, positive affectivity and negative affectivity to predict their physical health at Time 2(R²=.265). In case of retired elderly, suggested for the psycho-social determenants of subjective well-being and physical health by occupational classification. The implications of this study and the suggestions for furture study were discussed.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.5
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• pp.217-240
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• 2023

For a while, Functional cosmetics, Cosmeceutical cosmetics, and Derma cosmetics have gained trust and become popular due to the consumers' strong interest in ingredients & efficacy. It's remarkable that Clean or Vegan brands are growing fast because they are emphasizing on different values from the other cosmetic brands. It's needed to attempt to analyze the influence relationship between consumer lifestyle and social value in these changes, and to find out whether the consumption of vegan cosmetics is related to satisfying the need for self-expression in a social atmosphere where ESG is emphasized on. This study analyzed the effect of lifestyle types and self-expression needs on the purchase intention of vegan cosmetics by mediating social values for cosmetics consumers. Lifestyle types were classified into appearance-oriented, health-oriented, and fashion-oriented. For empirical analysis, 321 questionnaires collected from cosmetics consumers living across the country were used. SPSS v26.0 and PROCESS macro v4.2 were used to analyze based on a single mediating model as a single mediator. As a result of the analysis, first, lifestyle types and self-expression needs, excluding appearance-oriented types, were found to have a positive (+) effect on social values. Second, it was found that social value had a positive (+) significant effect on the purchase intention of vegan cosmetics. Third, appearance-oriented, health-oriented, trend-seeking lifestyle types and self-expression needs were all found to have a positive (+) effect on the purchase intention of vegan cosmetics. Fourth, social values were found to mediate lifestyle types, self-expression needs, and purchase intentions, except for appearance-oriented types. Appearance-oriented consumers do not directly affect social values but affect purchase intentions, suggesting that appearance-oriented consumers may not be significantly affected by product-related social values. In a comparison of the relative influence size using standardization coefficients, self-expression needs had the greatest impact on the purchase intention of vegan cosmetics when mediating social values, and health-oriented ones had the least impact. The academic implications of this study include contributing to consumer behavior research by providing insights, mediation mechanisms, and consideration of the niche consumer sector, and directing further research into the cosmetics industry beyond forming marketing strategies and sustainable business practices.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.2
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• pp.157-169
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• 2023

This study examined the effect of entrepreneurial orientation on creative behavior and the mediating effect of knowledge sharing behavior in the relationship between entrepreneurial orientation and creative behavior. In particular, this study examined the moderating effect of leader-member exchange (LMX) in the relationship between entrepreneurial orientation and creative behavior. In this study, after distributing 500 questionnaires to executives and employees working at small and medium-sized companies in Seoul and Gyeonggi-do, 259 questionnaires were used for hypothesis verification, excluding 38 unfaithful or missing responses. The analysis results are as follows. First, it was found that entrepreneurial orientation had a significant positive (+) effect on creative behavior. Second, it was found that entrepreneurial orientation had a significant positive (+) effect on knowledge sharing behavior. Third, knowledge sharing behavior was found to have a significant positive (+) effect on creative behavior. Fourth, knowledge sharing behavior was found to play a partial mediating role in the relationship between entrepreneurial orientation and creative behavior. Finally, it was found that LMX strengthened the positive (+) relationship between entrepreneurial orientation and creative behavior. The theoretical implications of this study are as follows. First, this study makes a theoretical contribution in that it revealed the mediating effect of knowledge-sharing behavior in the relationship between entrepreneurial orientation and creative behavior through empirical analysis of corporate members. Next, this study has theoretical implications in that it revealed that LMX strengthens the positive (+) relationship between entrepreneurial orientation and creative behavior. On the other hand, the practical implications of this study are as follows. First, companies need to find ways to strengthen the entrepreneurial orientation. Next, companies need to find ways to improve the quality of LMX between bosses and subordinates. Finally, this study discussed research limitations and future research directions.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.4
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• pp.37-50
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• 2023

Venture capital invests the necessary capital and supports management and technology in promising small and medium-sized venture companies in the early stages of start-up with promising technology and excellent manpower. It plays a role as a key player in the venture ecosystem that realizes profits by collecting the investment through various means after growth. Venture capital's job is to recruit various investors(LPs) to invest in small and medium-sized venture companies with growth potential through the formation of venture investment funds, and to collect investment as companies grow, distribute and reinvest. The main tasks of venture capitalists, which play the most important role in venture investment, are finding promising companies, corporate analysis and evaluation, investment screening, follow-up management, and investment recovery. Venture capital's success indicators are fund formation and return on investment, and venture capitalists are rewarded with annual salary, performance-based incentive, and promotion with work performance such as investment, exit, and fund formation. Compared to the recent rapidly growing venture investment market, investment manpower is insufficient, and venture capital is making great efforts to foster manpower and establish infrastructure and systems for long-term service, but research has been conducted mainly from a quantitative perspective. Accordingly, this study aims to empirically analyzed the impact of investment experience, delegation of authority, job fit, and peer relationships on fund formation and return on investment according to the characteristics of the venture capital industry. The results of these empirical studies suggested that future venture capital needs a job environment and manpower operation strategy so that venture capitalists with high job fit and investment experience can work for a long time.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.5
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• pp.67-80
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• 2022

This study was conducted to derive policy measures such as fostering and supporting by examining the actual conditions of domestic startups. The subject of this study was the start-ups located in Seongnam-si, where Pangyo Techno Valley, which is the highest-level innovation cluster in Korea and is evaluated as a start-up mecca. Startups were defined as startups under 7 years old based on new technologies such as IT, BT, and CT, and the subjects of the study were selected. This can be seen as a step forward from previous research in that it embodies the concept of a startup that was previously abstract in a quantitatively measurable way. As a result of the analysis, about 94% of startups are distributed in the so-called "Death Valley" growth stage, and startups above scale-up, which means full-scale growth beyond BEP, account for about 6%. appeared to be occupied. He cited the problem of start-up funds as the biggest difficulty in the early stages of startups, and cited the loan evaluation method that prioritizes sales or collateral in raising funds as the biggest problem. In addition, start-ups rated the access to private investment capital such as VC, AC, and angel investors at a low level compared to policy funds, which are public funds. Most startups showed a lot of interest in overseas expansion, and they chose matching overseas investors such as overseas VCs as the biggest support for overseas expansion. The overall competitiveness in the overseas market was 49.6 points, which is less than 50 points out of 100, indicating that the overall competitiveness was somewhat inferior. It was analyzed that public support and investment in overseas sales channels (sales channels, distribution networks, etc.) should be prioritized along with enhancement of technological competitiveness in order for domestic startups to increase their competitiveness in overseas markets as well as in the domestic market.

• Health Policy and Management
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• v.34 no.2
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• pp.211-221
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• 2024

Background: The public health crisis caused by coronavirus disease 2019 emphasizes the need to expand and strengthen public hospitals. However, the overall perception of public hospitals remains negative. This negative perception can hinder the roles and functions of public hospitals, so this study aims to analyze the factors affecting negative perceptions of public hospitals. Methods: We used data from a survey on the public healthcare of Chungcheongbuk-do residents conducted by the Chungcheongbuk-do Public Health Policy Institute, and 1,916 adults aged 19 or older who responded to the survey were included in the study. Logistic regression analysis was used to analyze the impact of experiences with public hospitals use and evaluations of public healthcare and public hospital policies on the negative perception of public hospitals. Results: The experience of not using public hospitals (adjusted odds ratio [aOR], 1.69; 95% confidence interval [CI], 1.04-2.74) and negative evaluations of public healthcare and public hospital policies were found to significantly impact negative perceptions of public hospitals. In public healthcare policies, negative evaluations of the provision of essential medical care (aOR, 4.14; 95% CI, 2.59-6.62), regional disparities (aOR, 1.59; 95% CI, 1.02-2.49), coverage (aOR, 1.99; 95% CI, 1.25-3.16), and quality of care (aOR, 2.39; 95% CI, 1.50-3.80) were significantly associated with negative perceptions of public hospitals. In public hospital policies, negative evaluations of facilities and equipment (aOR, 3.74, 95% CI, 2.36-5.94), medical specialties and services (aOR, 1.91; 95% CI, 1.21-3.01), and quality of medical service (aOR, 2.71; 95% CI, 1.72-4.25) were also significantly associated with negative perceptions of public hospitals. Conclusion: This study emphasizes the need to improve perceptions of public hospitals by considering the experience with public hospitals use and evaluation of public healthcare and public hospital policies.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.1
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• pp.41-50
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• 2010

We have developed an in-situ benthic chamber (BelcI) for use in coastal studies that can be deployed from a small boat. It is expected that BelcI will be useful in studying the benthic boundary layer because of its flexibility. BelcI is divided into three main areas: 1) frame and body chamber, 2) water sampler, and 3) stirring devices, electric controller, and data acquisition technology. To maximize in-situ use, the frame is constructed from two layers that consist of square cells. All electronic parts (motor controller, pA meter, data acquisition, etc.) are low-power consumers so that the external power supply can be safely removed from the system. The hydrodynamics of BelcI, measured by PIV (particle image velocimetry), show a typical "radial-flow impeller" pattern. Mixing time of water in the chamber is about 30 s, and shear velocity ($u^*$) near the bottom layer was calculated at $0.32\;cm\;s^{-1}$. Measurements of diffusivity boundary layer thickness showed a range of $180-230\;{\mu}m$. Sediment oxygen consumption rate, measured in-situ，was $84\;mmol\;O_2\;m^{-2}\;d_{-1}$, more than two times higher than on-board incubation results. Benthic fluxes assessed from in-situ incubation were estimated as follows: nitrate + nitrite = $0.18\;{\pm}\;0.07\;mmol\;m^{-2}\;d^{-1}$ ammonium $23\;{\pm}\;1\;mmol\;m^{-2}\;d^{-1}$ phosphate = $0.09\;{\pm}\;0.02\;mmol\;m^{-2}\;d^{-1}$ and silicate = $23\;{\pm}\;1\;mmol\;m^{-2}\;d^{-1}$.