• Journal of the Korean Solar Energy Society
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• v.39 no.3
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• pp.59-66
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• 2019

New and renewable energy forecasts are key technology to reduce the annual operating cost of new and renewable facilities, and accuracy of forecasts is paramount. In this study, we intend to build a model for the prediction of short-term solar power generation for 1 hour to 3 hours. To this end, this study applied two time series technique, ARIMA model without considering seasonality and SARIMA model with considering seasonality, comparing which technique has better predictive accuracy. Comparing predicted errors by MAE measures of solar power generation for 1 hour to 3 hours at four locations, the solar power forecast model using ARIMA was better in terms of predictive accuracy than the solar power forecast model using SARIMA. On the other hand, a comparison of predicted error by RMSE measures resulted in a solar power forecast model using SARIMA being better in terms of predictive accuracy than a solar power forecast model using ARIMA.

• Journal of Preventive Medicine and Public Health
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• v.52 no.5
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• pp.308-315
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• 2019

Objectives: Estimating influenza-associated mortality is important since seasonal influenza affects persons of all ages, causing severe illness or death. This study aimed to estimate influenza-associated mortality, considering both periodic changes and age-specific mortality by influenza subtypes. Methods: Using the Microdata Integrated Service from Statistics Korea, we collected weekly mortality data including cause of death. Laboratory surveillance data of respiratory viruses from 2009 to 2016 were obtained from the Korea Centers for Disease Control and Prevention. After adjusting for the annual age-specific population size, we used a negative binomial regression model by age group and influenza subtype. Results: Overall, 1 859 890 deaths were observed and the average rate of influenza virus positivity was 14.7% (standard deviation [SD], 5.8), with the following subtype distribution: A(H1N1), 5.0% (SD, 5.8); A(H3N2), 4.4% (SD, 3.4); and B, 5.3% (SD, 3.7). As a result, among individuals under 65 years old, 6774 (0.51%) all-cause deaths, 2521 (3.05%) respiratory or circulatory deaths, and 1048 (18.23%) influenza or pneumonia deaths were estimated. Among those 65 years of age or older, 30 414 (2.27%) all-cause deaths, 16 411 (3.42%) respiratory or circulatory deaths, and 4906 (6.87%) influenza or pneumonia deaths were estimated. Influenza A(H3N2) virus was the major contributor to influenza-associated all-cause and respiratory or circulatory deaths in both age groups. However, influenza A(H1N1) virus-associated influenza or pneumonia deaths were more common in those under 65 years old. Conclusions: Influenza-associated mortality was substantial during this period, especially in the elderly. By subtype, influenza A(H3N2) virus made the largest contribution to influenza-associated mortality.

• International Area Studies Review
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• v.14 no.2
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• pp.3-23
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• 2010

The purpose of the study is to estimate value of the Eulsukdo that is attracting lots of birds. Eulsukdo became one of the most famous eco-tourism destinations worldwide and environmental restoration work is progressing with enormous budget. The input of the budget by policy judgement basically can be justified when the benefit excesses the cost in social aspect. Eulsukdo has external effect as cultural tourism resource but it is difficult to estimate the value in market. The study is to estimate the value of Eulsukdo through the single-bounded dichotomous CVM(Contingent Valuation Methods). According to analysis results, the mean WTP(Willingness to Pay) and the truncated mean WTP are estimated at 5,240 and 3,374 won in the log-normal model, and 5,888 and 3,232 won in the log-logistic model respectively. The annual total benefits value based on the truncated mean WTP is estimated at 3,870 million won in the log-normal model and 4,040 million won in log-logistic model. The result of this study will provide useful guide to policy makers and developers who fully realize the value of public goods.

• Health Policy and Management
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• v.31 no.2
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• pp.225-231
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• 2021

Unmet healthcare is an important indicator to measure accessibility of healthcare services. To examine the latest status of unmet healthcare needs in South Korea, the four different data which is composed of nationally representative sample of South Korean population were used; the Korea Health and Nutrition Examination Survey (KNAHANES, 2007-2019), the Community Health Survey (CHS, 2008-2019), the Korea Health Panel Survey (KHP, 2011-2017), and the Korean Welfare Panel Study (KOWEPS, 2006-2019). The proportion of individuals reporting unmet healthcare needs were 5.8% (KNHANES), 5.3% (CHS), and 11.6% (KHP). Annual percentage change (APC) which identifies trend for the follow-up period was -9.5%, -8.0%, and -6.5%, respectively. The proportion of individuals reporting unmet healthcare needs due to cost were 1.1% (KNAHANES), 0.7% (CHS), 2.4% (KHP), and 0.4% (KOWEPS). The APC was -10.5%, -14.2%, -12.2%, and -19.6%, respectively. Compared to last year, the rate of unmet healthcare needs has declined in general. However, the low-income and the elderly population were reporting the highest rate of unmet health care needs, and the disparity between lowest and highest groups were remained. These results suggest that adequate benefit coverage is needed for low-income and elderly population.

• Korean Journal of Clinical Pharmacy
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• v.32 no.3
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• pp.155-165
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• 2022

Background: Chronic obstructive pulmonary disease (COPD) is not completely reversible and requires long-term management with appropriate treatment. This study aimed to analyze trends in treatment regimens and medication costs for COPD patients using a national claims database. Methods: We conducted this analysis using National Patient Sample data from the Health Insurance Review and Assessment Service covering the period from 2015 to 2018. We have constructed a dataset comprising COPD disease classification codes J43.x and J44.x (based on KCD-7 code, J43.0 was excluded) and compiled a list of drugs fitting current guidelines. To identify trends, we calculated frequency, ratio, and compound annual growth rate (CAGR) using the numbers of prescriptions and patients. Results: The number of COPD patients was 7,260 in 2018, slightly decreased from 2015. Most of these COPD patients were aged 60 or older and included a high proportion of males (72.2%; 2018). The number of patients prescribed inhaled medications increased gradually from 2015 to 2018 (9,227 (47.1%); 2015, 9,285 (51.5%); 2018), while the number of patients prescribed systemic beta-agonists and Xanthines has decreased since 2015 (CAGR -14.7; systemic beta-agonist, -5.8; Xanthines). The per capita cost of medication has increased by 0.4% (KRW 206,667; 2018, KRW 204,278; 2015) annually during the study period. Conclusion: This study showed that treatment with inhaled medications had continuously increased in accord with changing guidelines, but oral medications were still widely used. It is necessary to emphasize the importance of inhaled medications in treating COPD to reduce additional economic burden through appropriate medication use.

• Journal of Environmental Science International
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• v.31 no.1
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• pp.87-97
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• 2022

In this study, type analysis was conducted along with the advancement of basic data to calculate the maximum damage caused by strong winds during the typhoon period. The result of the damage by region showed that in 2012, the difference in damage was clearly distinguished as the region was classified in detail. In addition, the result of the annual damage in 2011 was strong on the west coast, and in 2016, the damage to the southeast coast was significant. In 2012, the 3-second gust was relatively stronger on the west and southeast coasts than in 2011, and the winds blew stronger along the southeast coast in 2016. Monthly damage data showed that the damage to the west coast was high in August, and the damage to the southeast coast was high in October from 2002 to 2019. The 3-second gust showed the result of wide expansion throughout the southern coast of the Korean Peninsula in October. As a result, the damage differs for type bacause the intensities and paths of typhoons vary depending on their characteristics, the 3-second gust blows differently by region based on regional characteristics, and the sale price is considered in metropolitan cities.

• Journal of Soil and Groundwater Environment
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• v.28 no.3
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• pp.12-28
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• 2023

Each national groundwater monitoring well showed distinct change patterns in groundwater levels and electrical conductivity (EC) in the Nakdong River Estuary, implying different external forces (EFs) on each well. According to the annual average data in 1997-2020, seawater was invaded into Well C. The desalination rate of -1,062 µS/cm/year represents the adaptive capacity of the well to seawater intrusion. The water levels and EC in Well E responded to precipitation, indicating the low absorptive capacity to climate changes. Meanwhile, Well B showed constant increases in water levels, suggesting that problems by rising groundwater should be considered in the study area where confined aquifers are overlaid by clay aquitards. The other wells showed consistent water levels and EC, indicating resilience to EFs. Here, resilience is the capacity of a well to resist changes by EFs, including the absorptive and adaptive capacity. The resilience of Wells E and F to climate changes was quantitatively compared using a resilience cost (RC). The RC showed Well F was more resilient than Well E, and the bedrock aquifer was more resilient than the alluvium aquifer, supporting the usefulness of RC. The resilience assessment against EFs (e.g., changes in land use and climate) helps sustainable groundwater management.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.131-133
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• 2021

Recently, the average cost of education per child has increased compared to the annual birthrate, which has been decreasing, and the quality of education has also changed. In this paper, we aim to provide more efficient delivery for language learning using Unity's Buforia techniques. Using an application using a smartphone's camera based on Unity, it provides effective language development by inducing interest to learners through sound along with three-dimensional pictures. By providing such education, parents can gain satisfaction in providing high-quality education to their children. For children learning, smartphones have the effect of becoming educational elements, not just watching videos or playing games. Finally, by improving the quality of education, it gives satisfaction to parents and gives children who learn a language as well as the perception that smartphones serve as educational devices.

• The Journal of Economics, Marketing and Management
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• v.3 no.3
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• pp.7-23
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• 2015

Women are more disadvantaged than men in many fronts and this confines them to informal sector livelihood activities. Any attempt to improve women's economic status will require information on the organization, cost and returns to investment in the livelihood activities in which they predominate. This is the issue for this study which compared yield performance in artisanal fishing and fresh fish marketing. Primary data collected through multi-stage sampling method were analyzed using inferential statistics, budgeting and regression models. Empirical findings revealed that about 75.0% of fisher folks either had no formal education or acquired only primary school education while 50.0% of marketers had secondary school education. The budgeting model revealed fisher-folks' and marketers' annual net profit to be N2,882,626.00 and N640,227.00, respectively. Profit from fishing was significantly higher than that of fish marketing. At 53.2% for fishing and 40.3% for marketing, returns to investment was better in fishing. Regression model results showed the significant factors influencing returns to each livelihood strategy to include fishing ground, distance covered and years of experience. The major constraint faced by operators of both livelihoods groups was insufficient credit. Despite this, the livelihood strategies were shown to be profitable ventures which contributed to households' consumption expenditure. Organizing women informal sector operators into groups to enhance access to government support and formal credit are recommended for improving livelihood strategy performance.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.3
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• pp.1-16
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• 2023

The purposes of this study were to investigate bag purchasing behaviors and design preferences of male and female adult consumers, and to find the differences depending on sex and age variable. A survey was conducted on 400 male and female adults from 20s to 50s. The questionnaire consisted of bag purchase behaviors, bag design preferences, and the subjects' demographic characteristics. The data were analyzed by Cronbach's α, factor analysis, x² test and t-test using SPSS. The results were as follows. First, as bag selection criteria, four factors (practicality, symbolism, aesthetics, and economics) were derived, and adult consumers considered economics as the most important among the factors. As for purchasing information sources, three factors (media, human resources, and store) were derived, and adult consumers considered human resources and store information sources more important than media. The main motive for purchasing bags was age and damage of the owned products, and Internet shopping malls were the most common purchasing place. The average annual cost of purchasing bags was 100,000 to 300,000 won, and the frequency of purchase was about once a year. Second, as bag preference images, four factors (individual, romantic, active, and classic image) were derived, and adult consumers preferred classic images the most. The shoulder bag was the most preferred as the bag shape, and black was the most preferred bag color. For the material, natural leather was the most preferred, and for the size, medium size was the most preferred. Third, bag purchasing behaviors and design preferences showed many significant differences according to the sex and age of the consumers. Therefore, the results of this study suggests that bag companies need to establish product development and marketing strategies in consideration of differences according to the sex and age group of adult consumers.