• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1277-1290
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• 2020

Water resources which is formed of surface and groundwater, are considered as one of the pivotal natural resources worldwide. Since last century, the rapid population growth as well as accelerated industrialization and explosive urbanization lead to boost demand for groundwater for domestic, industrial and agricultural use. In fact, better management of groundwater can play crucial role in sustainable development; therefore, determining accurate location of groundwater based groundwater potential mapping is indispensable. In recent years, integration of machine learning techniques, Geographical Information System (GIS) and Remote Sensing (RS) are popular and effective methods employed for groundwater potential mapping. For determining the status of the integrated approach, a systematic review of 94 directly relevant papers were carried out over the six previous years (2015-2020). According to the literature review, the number of studies published annually increased rapidly over time. The total study area spanned 15 countries, and 85.1% of studies focused on Iran, India, China, South Korea, and Iraq. 20 variables were found to be frequently involved in groundwater potential investigations, of which 9 factors are almost always present namely slope, lithology (geology), land use/land cover (LU/LC), drainage/river density, altitude (elevation), topographic wetness index (TWI), distance from river, rainfall, and aspect. The data integration was carried random forest, support vector machine and boost regression tree among the machine learning techniques. Our study shows that for optimal results, groundwater mapping must be used as a tool to complement field work, rather than a low-cost substitute. Consequently, more study should be conducted to enhance the generalization and precision of groundwater potential map.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.87-96
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• 2021

Information and Communication Technology (ICT) remote soil moisture control system including soil sensing, automatic water supply chain, and remote alarming system was established on reclaimed land and operated stably. The system was operated using river water around the reclaimed land without fertilizer. On applying this system to control soil moisture, the kenaf germination rate was improved up to two times. Kenaf biomass was 4,748 kg/10a and was higher than that of untreated soil moisture management. When the nutritious liquid fertilizer was used, kenaf yield reached 8,390 kg/10a, which was lower than 10,848 kg/10a of the non-reclaimed land treated with standard chemical fertilizers. As the soil moisture was managed stably through the ICT remote soil moisture control system, the quality of the kenaf crop was improved, resulting in a 7% increase in dry weight, and a 11.5% increase in plant hardness. The estimated kenaf yield was 5,039 kg/10a when 800 tonnes of water were supplied by the ICT remote soil moisture control system with the stream water around Saemangeum reclaimed land without chemical fertilizers and organic matter.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.4
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• pp.149-156
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• 2021

OTT service, which allows video content to be viewed as a streaming service on the Internet network, has recently attracted a lot of attention, and the number of users is also increasing rapidly. It would be a natural strategy for OTT companies to acquire more content to gain a competitive advantage in relations with traditional media companies and other OTT companies. However, there are research results to show that the investment in facilities by Internet service providers who must transport the increasing Internet traffic from OTT provider to end users should increase as the amount of Internet traffic originated by OTT services also increases. This study empirically analyzed how content investment by Netflix, a leading OTT company, affects its revenue growth and network investment by Internet service providers through a polynomial distributed lag model. And the analysis results show that Netflix's content investment contributes to the company's increase in revenue, and also has an effect on the increase in network investment by Internet service providers. This result confirms that OTT operators' content acquisition strategy is a valid management strategy, and empirically supports the study results that OTT operators need to share the cost of Internet network facility investment.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.353-366
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• 2022

The study sets out to examine the relationship between the effects of government support, network capability, and knowledge sharing on the effects of innovative behavior on innovation performance. As digital-based networks and knowledge sharing activities are rapidly becoming common in the era of the spread of Covid-19, 357 questionnaires were analyzed for incumbent employees and the research hypotheses are verified using SPSS 24 and smart PLS 3 to prove the relationships between variables. As a result of the study, it is found that innovation performance increased when government support, network capability, and knowledge sharing increased. Innovative behavior is found to significantly mediate the relationship between network capability, knowledge sharing, and innovation performance, and government support was found to have a significant effect on network capabiltiy. Therefore, in order to induce innovative actions that are important in creating innovative results, various programs to enhance the network capabilities of entrepreneurs and promote knowledge sharing should be required as government support policies. This will serve as a driving force for entrepreneurs to voluntarily develop and implement ideas more flexibly and freely, thereby enhancing competitiveness through innovative growth of companies and industries. In other words, this study verified the effectiveness of government support in the network capability to help create innovative results by inducing innovative behavior along with knowledge sharing activities, and comprehensively demonstrated the relationship between factors in the overall structure.

• The Journal of Information Systems
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• v.30 no.4
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• pp.173-202
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• 2021

Purpose This study explored overall phenomena in context such as YouTube channel operation, strategy, and profit generation through interviews with two research participants who started their own businesses and are recognized as influencer on YouTube and analysis of viewer responses to uploaded contents. With the explosive growth of YouTube content provision and use, previous studies on YouTube are only being conducted individually on YouTube's content, influence, and content providers, so it is need to explore YouTube channel operations and the effect of revenue generation in context from an integrated perspective. Therefore, the purpose of this study is to present an integrated model that provides a specific process by contextually linking the factors and results influencing YouTube channel operation and revenue generation phenomena to individuals and companies who are trying to operate YouTube channels for the first time. Design/methodology/approach This study systematized and structured the overall phenomena in context such as YouTube channel operation, communication strategy, effect on revenue generation, and YouTube channel operation results by selecting interview subjects and collecting data through interviews, and analyzing viewer reactions (likes, comments, etc.). Due to the lack of previous studies exploring integrated phenomena, research analysis used Strauss & Corbin (1998)'s grounded theory approach, which presented inductive research methods to discover new theories by structuring concepts and categories based on detailed observations and information provided by interviewees. Findings The academic implication of this study is that while previous studies are conducted as individual studies on YouTube's content, influence, and content providers in the current situation where YouTube content provision and use are exploding, it integrally explores and presents an integrated model throughout the process. In addition, taking into account the lack of previous studies, it can be found in the aspect of using the grounded theory approach, an inductive theory approach that establishes a new theory. The practical implications can be found in that it presented practical directions to beginners who want to start operating YouTube channels by identifying operational preparations, communication strategies with viewers, and response management strategies.

• Journal of Industrial Convergence
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• v.19 no.6
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• pp.21-35
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• 2021

The purpose of this paper is to examine how demand for labor affects the job seeker's decision on the level of investment in education. In the current paradigm of economic growth in which innovations and technological developments generally weaken the strength demand for labor and increases the uncertainty related to employment, this paper provides a theoretical framework that can be used as a basic framework in understanding the decision of investment in education in varying conditions of demand for labor. The following are the findings of this paper. First, the level of investment in education can generally be regarded to be higher as the demand for labor exacerbates but for the job seekers with a certain characteristic. Second, the Arrow-Pratt absolute risk-aversion measure is the characteristic of the job seeker that determines in what direction the job seeker changes in the level of investment in education, For an arbitrary level of demand for labor there exists a certain threshold which determines the minimum degree of risk-aversion required for the job seeker's Arrow-Pratt should go over to increase the level of education as demand for labor weakens. Third, the job seekers lower the level of education even though the demand condition in labor markets weakens if the compensation function does not depend on the level of education. This is surprising because it turns out that one of the reasons why job seekers invest in education is that they want to be recognized in their compensation for their level of education even when more education still raises the probability of employment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.549-566
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• 2022

Recently, artificial intelligence (AI) technology has progressed rapidly, and industries using this technology are significantly increasing. Further, analysis research using text mining, which is an application of artificial intelligence, is being actively developed in the field of social science research. About 125 laws, including joint laws, have been enacted under the Ministry of Oceans and Fisheries in various sectors including marine environment, fisheries, ships, fishing villages, ports, etc. Research on the laws under the Ministry of Oceans and Fisheries has been progressively conducted, and is steadily increasing quantitatively. In this study, the domestic research trends were analyzed through text mining, targeting the research papers related to laws of the Ministry of Oceans and Fisheries. As part of this research method, first, topic modeling which is a type of text mining was performed to identify potential topics. Second, co-occurrence network analysis was performed, focusing on the keywords in the research papers dealing with specific laws to derive the key themes covered. Finally, author network analysis was performed to explore social networks among authors. The results showed that key topics have been changed by period, and subjects were explored by targeting Ship Safety Law, Marine Environment Management Law, Fisheries Law, etc. Furthermore, in this study, core researchers were selected based on author network analysis, and the tendency for joint research performed by authors was identified. Through this study, changes in the topics for research related to the laws of the Ministry of Oceans and Fisheries were identified up to date, and it is expected that future research topics will be further diversified, and there will be growth of quantitative and qualitative research in the field of oceans and fisheries.

• Smart Media Journal
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• v.11 no.5
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• pp.9-16
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• 2022

Recently, agricultural sites are automating into digital agricultural smart farms by applying technologies such as big data and Internet of Things (IoT). These smart farms aim to increase production and improve crop quality by measuring the environment of crops, investigating and processing data. Production prediction is an important study in smart farm digital agriculture, which is a high-tech agriculture, and it is necessary to analyze environmental data using big data and further standardized research to manage the quality of growth information data. In this paper, environmental and production data collected from smart farm strawberry farms were analyzed and studied. Based on regression analysis, crop production prediction models were analyzed using Ridge Regression, LightGBM, and XGBoost. Among the three models, the optimal model was XGBoost, and R2 showed 82.5 percent explanatory power. As a result of the study, the correlation between the amount of positive fluid absorption and environmental data was confirmed, and significant results were obtained for the production prediction study. In the future, it is expected to contribute to the prevention of environmental pollution and reduction of sheep through the management of sheep by studying the amount of sheep absorption, such as information on the growing environment of crops and the ingredients of sheep.

• Journal of Naturopathy
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• v.11 no.2
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• pp.136-142
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• 2022

Background: We are necessarily considering changes in the parasite infection rate and methods in Korea from 1970 to the present from the perspective of natural healing. Purposes: This study was to investigate how the difference in the rate of reduction in infection rate has changed and progressed to the present. Methods: A literature review was conducted. Results: Until the 1970s, Korea had one of the highest parasite infection rates. The Parasitic Disease Prevention Act was enacted to control the infection rate in 1966. From 1969, the nationwide national parasite management project was conducted for all students twice a year to treat all parasitic eggs until 1995. In addition, the government commissioned the Korean Association for Parasite Eradication (KAPE) to conduct a national parasite infection survey eight times, from 1971 to 2012, every two years. As a result, the overall egg positive rate of parasite was 84.3% in 1971 but decreased to 2.6% in 2012. In addition, Ascaris lumbricoides, Paragonimus westermani, Taenia spp., and intestinal protozoa were significantly reduced nationwide. Conclusions: Successful control in Korea is judged to have achieved a successful effect by systematically managing national economic growth, social consensus on parasite eradication, improved professional parasite prevention guidelines, and supply of effective anthelminthics.

• Journal of Nutrition and Health
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• v.55 no.2
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• pp.201-210
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• 2022

Vitamin A (Vit A) is a lipid-soluble vitamin required for diverse normal body functions, including good vision, reproduction, growth, development, and cellular differentiation. The therapeutic effects of Vit A have been demonstrated for the treatments of inflammation, low immunity, and cancer. The present review discusses the scientific evidence for establishing the 2020 Dietary Reference Intakes for Koreans (KDRI) for Vit A, issues caused by unit change of Vit A, and suggestions for the 2025 KDRI revision. Due to the changes in the standard bodyweight observed in several age groups, the 2020 KDRI had minor revisions as compared to the 2015 KDRI. In the 2015 KDRI, the Vit A unit has changed from retinol equivalent (RE) to retinol activity equivalent (RAE) and the activity of carotenoids became half with RAE compared to RE due to this unit change. Since the Vit A intake of Koreans relies heavily on plant-based carotenoids, the dietary intake of Vit A in Koreans as determined by considering the RAE was much lower than values obtained with RE. The analysis for Vit A intake by the Korean National Health and Nutrition Survey only reflects intakes of retinol and beta-carotene. Thus, it would be necessary to include the consumption of other provitamin A, such as alpha-carotene and beta-cryptoxanthin. Moreover, assessing the amounts of Vit A in foods should be customized to Korean diets since there are seasonal variations in the carotenoid concentration of plants. Moreover, other factors such as age- and sex-specific intake data and considerations of baseline micronutrient status, body mass index, and dietary patterns should be considered for developing more precise KDRI. In particular, the Vit A requirement needs to be met by consuming diverse foods, including animal foods.