• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.35-41
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• 2008

Nutrient Enrichment Bioassays (NEBs) were conducted in the laboratory during June $22{\sim}28$, 2006 in order to determine primary limiting factor on the phytoplankton growth. For the NEBs, the water was sampled using a 10L polyethylene-lined container and dispensed into 2.5L container in the laboratory. The algal growths response in the control (C) and three treatments of phosphorus (P), 2-fold phosphorus (2P), and nitrate nitrogen $(NO_3-N)$ were monitored during 7 days. In the cubitainers which were spiked as P (T1) and 2P (T2) Chl-${\alpha}$ concentrations were decreased during the test period and the final concentrations was low than initial values. However, Chl-${\alpha}$ in the cubitainers which were spiked as $NO_3$(T3) and $P+NO_3$(T4) showed significant increases compared to the initial values, indicating that in the short-term experiments, nitrogen seemed to be a primary limiting nutrient during the periods of NEBs experiment. Long-term ambient nutrient data of TP and TN, and TN:TP mass ratios, however, showed a potential phosphorus limitation on phytoplankton growth and previous other researchers showed a variations of limiting nutrients by nitrogen or phosphorus depending on the seasons sampled and locations. In this study nitrogen as primary limiting nutrient in the NEBs seem to be an seasonal effect rather than the consistent nitrogen limitation.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.105-113
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• 2013

Consumer organizations usually lead the opinions of the consumers. This study was performed to investigate the perceptions and information needs of consumer organizations on food additives for the promotion of risk communication. A survey was conducted for 4 weeks in March 2012 by using a self-administered questionnaire consisting of 32 questions. Total 111 responses were collected for analysis. 'Safety (91.0%)' was the most important factor influencing the purchase of processed food, and both 'food additives (24.3%)' and 'environmental pollution (23.4%)' were considered as main risk factors. The longer the career of the members had, the higher negative perceptions on food additives (p<0.01). About 70% of the respondents who had known KFDA's researches on evaluating safety of food additives answered that researches were not enough to make sure the safety. Although lectures and other domestic organization were the main channels for getting information, 'TV' was considered as the most suitable way for it. 'Poor risk communication (32.4%)' was pointed out as the serious problem of government's food safety policy. Based on these results, consumer organizations' low level of trust on government should be overcome by continuous supply of information what they need to facilitate risk communication on food additives.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.35-55
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• 2008

Assessing vulnerability to climate change is the first step to take when setting up appropriate adaptation strategies. Adaptive capacity to climate change is the important factor comprising vulnerability. An adaptive capacity index in agricultural water management system was developed considering agricultural water supply and demand for rice production in Jeolla-do, Korea. The agricultural water supply was assumed to be equal to the amount of water stored in the major agricultural reservoirs, while data on the agricultural water demand was obtained from the dynamic simulation results by Korea Agriculture Corporation(KAC). The spatial unit for analysis was conducted at the county(Si, Gun, Gu) level and temporal scale was based on every month from 1991-2003. Adaptive capacity for drought stress index(ACDS index) was calculated as the percentage of data points where the irrigated water supply was greater than the crop water demand. The ACDS index was compared with SWSCI(Standard Water Storage Capacity Index) and the relationship showed high degree of fit($R^2$=0.84) using the exponential function, indicating that the developed ACDS index is useful for evaluating the status of the balance between agricultural water supply and demand, especially for the small sized agricultural reservoirs. This study provided the methodological basis for developing climate change vulnerability index in agricultural water system which is projected to be more frequently exposed to drought condition in the future due to climate change. Further research should be extended to the study on the water demand of the crops other than rice and to the projection of the change in ACDS index in the future.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.75-89
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• 2021

Currently, small business owners are facing a situation where it is difficult to run their business in the existing way due to the spread of digital technology and the prolonged COVID-19. As a necessary competency for them, this study focused on digital literacy and examined the relationship between digital literacy and individual and market characteristics, business performance of small business owners. The specific research purpose is to examine the effect of entrepreneurial characteristics, which are individual factors, and market characteristics, which are environmental factors, on business performance and the mediating effect of digital literacy. In previous studies, various factors explaining the business performance of small business owners were reviewed, and innovation and self-determination, which are entrepreneurial characteristics of small business owners, and market competition and growth were derived as independent variables, and financial and non-financial performance were set as dependent variables. The hypothesis was established as digital literacy was expected to play a role in mediating the relationship between independent and dependent variables. For empirical research, a survey was conducted on small business owners across the country, and the analysis results are summarized as follows. It was found that the innovation and self-determination of small business owners had a positive (+) significant effect on financial and non-financial performance. In addition, it was confirmed that the degree of competition in the market had no significant effect on financial and non-financial performance, and that the growth of the market had a significant positive (+) effect on financial and non-financial performance. In the case of the mediating effect of digital literacy, it was confirmed that innovation had a partial mediating effect on non-financial performance, and digital literacy had a complete mediating effect on the effect of market competition on financial and non-financial performance. Finally, it was confirmed that digital literacy has a partial mediating effect on the effect of market growth on non-financial performance. Looking at the results, it can be seen that the entrepreneurial characteristics of small business owners, which correspond to innovation and self-determination, directly act as a factor to increase business performance, and market characteristics indirectly increase digital literacy to achieve results. Based on the above research results, the implications and limitations of the study and future research directions were presented together.

• Journal of Nutrition and Health
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• v.52 no.3
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• pp.297-309
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• 2019

Purpose: This study examined the relationship among the use of food-related content (FRC), dietary behaviors, and dietary self-efficacy to demonstrate the need for nutrition education to help adolescents build healthy eating habits and provide evidence for developing nutrition education programs for adolescents. Methods: Three hundred and eighty-one high school students in Seoul and Gyeonggi areas participated in the study. The subjects were divided into three groups (low, medium, and high) according to the level of use of the FRC, and their general characteristics, dietary behaviors, and dietary self-efficacy were analyzed. Correlation analysis was performed between FRC usage, dietary behaviors, and dietary self-efficacy, and the mediating effects of dietary self-efficacy on the relationship between the level of the use of FRC and dietary behaviors were estimated. Results: A higher level of FRC usage was associated with an increased daily cost of eating out and snacking, but no difference was observed in the BMI range. The subjects in a group with a high level of FRC usage ate convenience store or instant foods instead of homemade meals (p = 0.033), had a late-night meal or snack (p = 0.024), and turned to emotional eating under stress (p < 0.001) more than those in the low level group. In addition, the high level group checked the nutrition facts label more carefully when purchasing processed foods (p = 0.016) and exercised at least 30 minutes daily, not considering physical education classes (p = 0.057). The higher level of FRC use, the lower the dietary self-efficacy, whereby the subscales 'environmental stimulus control efficacy' and 'affective factor control efficacy' showed complete mediating effects. Conclusion: Given that FRC has been increased recently, adolescents are in need of support to help them control and enhance their dietary self-efficacy as well as develop healthy dietary behaviors through proper nutrition education programs.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.205-212
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• 2023

This study was attempted to find out how the ecological niche and interspecies relationship of Quercus aliena and Q. serrata, which are the main constituents of potential natural vegetation along the riverside of mountains in Korea, under climate change conditions. To this end, soil moisture and soil nutrients were treated with 4 grad ients under climate change conditions with elevated CO₂ and temperature, plants we re harvested at the end of the growing season, growth responses of traits were measured, ecological niche breadth and overlap were calculated, and it was compared with that of the control group(ambient condition). In addition, the relationship between the two species was analyzed by principal component analysis using trait values. As a result, the ecological niche breadth of Q. aliena was wider than that of Q. serrata under the moisture environment conditions under climate change. Under nutrient conditions, the ecological niche of the two species were similar. In addition, the ecological overlap for soil moisture of Q. aliena and Q. serrata was wider than the soil nutrient gradient under climate change. The species with traits in which the increase in ecological niche breadth due to climate change occurred more than the decrease was Q. aliena in both water and nutrient gradients. And in the responses of the population level, due to climate change, the adaptability of Q. aliena was higher than that of Q. serrata under the soil moisture condition, but the two species were similar under the nutrient condition. These results mean that the competition between the two species occurs more severely in the water environment under climate change conditions, and at that time, Q. aliena has higher adaptability than Q. serrata.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.595-601
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• 2008

The purpose of this study is to investigate the trends and patterns of various kind of water uses in a household by metering in Korea. Water use components are classified by toilet, washbowl, bathing, laundry, kitchen, miscellaneous. Flow meters are installed in 140 household selected by sampling in all around Korea. The data are gathered by web-based data collection system from the year 2002 to 2006, considering pre-investigated data such as occupation, revenue, family members, housing types, age, floor area, water saving devices, education, miscellaneous. Reliable data are selected by upper fence method for each observed water use component and statistical characteristics are estimated for each residential type to determine liter per capita per day. Estimated domestic per capita day show an indoor water use with the range from 150 lpcd to 169 lpcd for each housing type as the order of high rise apartment, multi-house, and single house. As the order of consuming amount among water use components, it is investigated that toilet (38.5 lpcd) is the first, and the second is laundry water (30.8 lpcd), the third is kitchen (28.4 lpcd), the fourth is bathtub (24.7 lpcd), the next is washbowl (15.4 lpcd). The results are compared with water uses in U.K. and U.S. As life style has been changed into western style, pattern of water use in Korea is tend to be similar with the U.S. water use pattern. Compared with the surveying results by Bradley, on 1985. Thirty liter of total use increased with the advancement of economic level, and a little change of water use pattern can be found. Especially, toilet water take almost half part of total water use and laundry water shows lowest as 11% in surveying at the year of 1985. But, this study shows that 39 liter, 28% of toilet water, has been decreased by the spread of saving devices and campaign. It is supposed that the spread large sized laundry machine make by-hand laundry has been decreased and water use increased. Unit water amount of each end-use in household can be applied to design factor for water and wastewater facilities, and it play a role as information in establishing water demand forecasting and conservation policy.

• Research in Plant Disease
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• v.30 no.2
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• pp.139-147
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• 2024

Erwinia amylovora is a gram-negative plant pathogen that causes fire blight in apple and pear trees, resulting in significant damage worldwide. In this study, we monitored the emergence of fire blight from 2019 to 2023 to determine the emergence patterns and the factors affecting the outbreak of the disease. As a result of the 5-year survey on the emergence of fire blight, a total of 2,029 cases have emerged, mostly in apple trees of 1,378 cases (67.9%) followed by 645 cases (31.8%) in pear trees, and from quince, hawthorn, and mountain ash trees. Fire blight appeared in specific areas of Gyeonggi, Chungnam, Gangwon, and Chungbuk provinces in 2019, but spread to Andong and Yesan in 2021, Muju and Bonghwa in 2023. In 2020 and 2021, there were 744 and 618 cases of fire blight outbreaks, respectively, compared to other years (188-245 cases/year). Notably, 914 of these cases were observed in apple trees from May to July, with 667 cases reported in Chungju and Jecheon. The incidence of fire blight was positively correlated with the daily maximum temperatures and rainy days in January and February, as well as the rainy days in May and June. The average age of the diseased pear trees was 25 years, higher than the 10-year average age of the apple trees. This study provides fundamental information to understand the status and factors affecting the fire blight emergence in Korea. Prevention measures should be established through continuous analysis of the status of fire blight.

• Journal of Nutrition and Health
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• v.57 no.1
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• pp.136-152
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• 2024

Purpose: A comprehensive evaluation item was developed to assess adolescent dietary habits and nutritional practices, considering food intake, eating behaviors, and food culture, such as social support and food environment. Methods: The 59 candidate items of the evaluation checklist were obtained based on the results of the eighth Korea National Health and Nutrition Examination Survey data, Korea Dietary Reference Intakes, dietary guidelines for adolescents, Youth Risk Behavior Survey data, national nutrition policies and dietary guidelines, and literature reviews. Four hundred and three middle and high school students residing in metropolitan areas participated in a survey using the 58-item checklist, which was selected through expert evaluation and content validity ratio analysis. The construct validity of the assessment tool for the quality of adolescent diets was assessed by exploratory factor analyses to determine if the checklist items were organized properly and whether the responses to each item were distributed adequately. Results: The Bartlett sphericity test was significant for each area (p <0.001), and the eigen values were greater than one. The Kaiser-Meyer-Olkin and cumulative proportions by areas were food intake (0.765 and 56.8%, respectively), eating behaviors (0.544 and 64.8%, respectively), and food environment (0.699 and 62.4%, respectively). Twenty-two checklists were determined for the final evaluation items for the adolescents' dietary habits and nutritional practices and were categorized into three distinct factors: food intake (10 items), eating behaviors (4 items), and food environment (8 items). Conclusion: The evaluation items for adolescent dietary habits and nutritional practices is a useful checklist for easily and quickly assessing the dietary qualities and reflecting Korean adolescents and their food environmental factors related to a sustainable diet.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.3
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• pp.27-40
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• 2024

This study empirically derives the factors affecting the practice of corporate social responsibility (CSR) of venture firms in Korea from the perspective of Slack Resource Theory and the company's growth strategy, and provides implications for future expansion of venture firm's CSR activities. In Korea, venture firms have grown into important players in the national economy since the late 1990s through social contributions such as economic value creation, job creation, and technological development. As venture companies grow in status, positive relationships with stakeholders and responsibility for environmental and social values are required. Now, CSR is becoming an important strategic choice for SMEs and venture firms. However, until now, CSR-related academic research has mainly focused on large or listed corporations, and there is not much research on SMEs or venture firms. In particular, research on the factors that lead venture companies to make important business decisions of participating in CSR activities is not there yet. This study applied logistic multiple regression analysis using the '2023 Survey on Venture Firms' conducted by the Ministry of SMEs and Startups. As a result of this study, operating profit, which is an available resources of venture companies, and government support, which is a potential resource, have a positive impact on venture firms's CSR activities. Also, business relationships with large corporations and expectation for future cooperation also have a positive impact on CSR activities as the determinants. On the other hand, it was analyzed that in venture firms where ownership and management are not separated, the higher the CEO's shareholding ratio, the more negatively it affects CSR activities. This study contributes academically as the first empirical study on the determinants of CSR activities of venture firms in Korea and provides implications that government policy support and collaboration between large corporations and venture firms are important in order to expand CSR activities of venture firms.