• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.582-587
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• 2022

Biphasic solvents are attracting attention as energy-reducing solvents for capturing CO₂ from flue gas in combustion process. In this study, considering diethylenetriamine (DETA) and diethylethanolamine (DEEA) mixed solvents, one of the biphasic solvents by blending of two types of amines, the CO₂ absorption rates of DETA and DEEA was measured by wetted wall column. The effects of DETA and DEEA concentrations and operating temperature on the overall mass transfer coefficient were investigated. As a result, the overall mass transfer coefficient was proportional to the DETA concentration. However, in the case of the DEEA concentration, the effect was small and when the concentration was exceeded, the overall mass transfer coefficient decreased. The DETA aqueous solution showed little change in the overall mass transfer coefficient with the operating temperature, whereas the DEEA aqueous solution increased the overall mass transfer coefficient with the operating temperature. As a result of obtaining the observed reaction rate constant under the pseudo-first-order reaction assumption, it was found that the observed reaction rate constant in DETA aqueous solution was proportional to the DETA concentration, but DEEA did not fit the pseudo-first-order reaction assumption.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.5
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• pp.405-412
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• 2022

This paper studies the method of estimating power loss and classifying the factors for improving the power generation efficiency through O&M. It is installed under various climatic conditions worldwide, operational and maintenance technologies suitable for the characteristics of the installation location are required. Existing studies related to solar power generation efficiency have been actively quantifying the impact on short-term losses by environmental factors such as high temperature, dust accumulation, precipitation, humidity, and wind speed, but analysis of the overall impact from a long-term operation perspective is limited. In this study, the potential for efficiency improvement was analyzed by re-establishing a loss classification system according to the power flow of solar power to derive a comprehensive efficiency model for long-term operation and estimating power loss through a case study for each region where climate conditions are classified. As a result of the analysis, the average annual potential for improving soiling loss was 26.9%, Death Valley 7.2%, and Seoul 3.8%. Aging losses was 6.6% in the 20th year as a cumulative. The average annual potential due to temperature loss was 2.9 % for Doha, 1.9% for Death Valley, and 0.2% for Seoul.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.967-977
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• 2022

The occurrence and intensity of wildfires are increasing with climate change. Emissions from forest fire smoke are recognized as one of the major causes affecting air quality and the greenhouse effect. The use of satellite product and machine learning is essential for detection of forest fire smoke. Until now, research on forest fire smoke detection has had difficulties due to difficulties in cloud identification and vague standards of boundaries. The purpose of this study is to detect forest fire smoke using Level 1 and Level 2 data of Geostationary Environment Monitoring Spectrometer (GEMS), a Korean environmental satellite sensor, and machine learning. In March 2022, the forest fire in Gangwon-do was selected as a case. Smoke pixel classification modeling was performed by producing wildfire smoke label images and inputting GEMS Level 1 and Level 2 data to the random forest model. In the trained model, the importance of input variables is Aerosol Optical Depth (AOD), 380 nm and 340 nm radiance difference, Ultra-Violet Aerosol Index (UVAI), Visible Aerosol Index (VisAI), Single Scattering Albedo (SSA), formaldehyde (HCHO), nitrogen dioxide (NO₂), 380 nm radiance, and 340 nm radiance were shown in that order. In addition, in the estimation of the forest fire smoke probability (0 ≤ p ≤ 1) for 2,704 pixels, Mean Bias Error (MBE) is -0.002, Mean Absolute Error (MAE) is 0.026, Root Mean Square Error (RMSE) is 0.087, and Correlation Coefficient (CC) showed an accuracy of 0.981.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.217-225
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• 2021

This study analyzed domestic research trends related to the behavior of problems with using smart devices in infants, focusing on addiction tendency. The main results of research trends are as follows: First, the total number of papers published per year is 79, and addiction proneness studies were published in various academic journals, while researchers' major was mostly concentrated in the department of education and social welfare. Second, there were 81 research topics, including actual conditions, scale development, related variables, interventions, and causal relationships. The proportion of research subjects was the highest with 60 (74.1%) research subjects, which are related variables. Third, the subjects of the study were divided into infants, caregivers, and teachers, and the main subjects of the study were mothers. Fourth, the research trends by research method were 73 quantitative studies (92.4%), 2 qualitative studies, 1 literature study, 2 mixed studies, and 1 other study. Fifth, the results of the analysis of influential factors were classified as risk factors and protection factors, which were specifically classified as individual factors, household factors, and social and environmental factors. Based on the study results, further discussion and practical suggestions were added.

• Journal of the Korean Society of Floral Art and Design
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• no.43
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• pp.39-56
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• 2020

This study is on the creation of floral art works based on the intuitive insight acquired by methodological process of ruminating the experienced meaningful events of the artists utilizing sensible perception. The researcher used the narration and visualization techniques. The narration process adopted the writing technique of subjective impression, emotion, stream of consciousness to capture sensations of subconscious state, which were applied in three steps of 'the exploration of experiences', 'the concretion of experiences', and 'the creation of meaning out of experiences'. The visualization process adopted collection, selection, classification, and interpretation of related images, which were applied in three methods of 'the creation of images', 'the utilization of intuition', and 'the perception through remembering'. Finally 5 art works of 'Hammock is Good', 'At the Rooftop with Warm Sunshine', 'Standing at the Waterside Alone', 'Dizziness at Hot Sand Field', and 'Having Good Time at a Botanical Garden'were created through the combination of these two methods mentioned above and complementary research and writing. The meaningfulness of this research lies in presenting methodological approaches of utilizing narration and visualization of experiences in art creation process.

• Journal of Korea Entertainment Industry Association
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• v.14 no.4
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• pp.211-222
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• 2020

The purpose of this study is to investigate how the influence of sensory weight on the physical fitness participants affects exercise passion and psychological well-being, and to provide basic data for improving the quality of life and well-being of the people. In order to achieve the purpose of this study, data were collected using participants' sensation seeking tendency, excercise passion, and psychological well-being scale, and various statistical analyzes were performed to obtain the following results. As a result of the analysis, first, it was found that there was a difference in sensation seeking tendency, exercise passion, and psychological well-being according to the gender of participants in leisure sports. Second, there was a difference in sensation seeking tendency, exercise passion, and psychological well-being according to the careers of participants in leisure sports. Third, the thrill and adventure of the sensation seeking tendency had a positive effect on the pleasure, immersion, and confidence of the psychological well-being, while pursuing experience on the self-realization of the psychological well-being, but it was found that the sense of boredom had a negative effect on the immersion of the psychological well-being. Fourth, the thrill, adventure, and pursuit of experience among the sensation seeking tendencies had a positive effect on the harmonious passion of exercise passion, but negative effect on the sense of boredom. Finally, it was found that exercise passion had a positive effect on all sub-factors of psychological well-being.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.129-159
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• 2022

This study generated primary data for supporting the place branding as a part of the library advertising and marketing strategies to increase public library visits. The literature review enabled the use of the place branding concepts to discover the relationships among the constituent parts, factors, expected outcomes, and loyalty, then to develop the research model and the hypothesis, which were verified using the Structural Equation Model. There were 34 research hypotheses, of which 21 were adopted. The place image factors such as library reliability, library reciprocity, and library safety were found to be significant. This study derived social contribution value as new place value and place image factors as the potential brand image of public libraries. It helped select the place image factors that best fit the local library's core values (i.e., place value). This study is meaningful because it is a fundamental study to introduce place branding in public libraries as an advertising and marketing strategy. And it is expected that public libraries will grow into high-quality brands with high awareness, loyalty, and secure leadership in the local community.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.4
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• pp.81-93
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• 2022

There are many natural hot springs and mineral springs as well as the cultural heritage of the three kingdoms period in the Geum River basin including Chungcheong region. No specific regeneration and publicity plans for deteriorated facilities in this area has been presented. This study aims to suggest promising hot spots and complex water culture belt in the Chungcheong region and Geum River basin through the spatial interpretation of resources. The northern part of the Geum River basin is expected to become a therapeutic spring belt with many hot springs and CO₂-rich springs. In the central and southern parts of the Geum River basin, it is considered that it will be possible to promote convergence publicity by using groundwater resources and cultural assets.

• Journal of the Korean Geotechnical Society
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• v.38 no.12
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• pp.19-28
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• 2022

Cavities behind concrete walls can adversely affect the stability of structures. Thus study aims to detect cavities behind concrete structures using a microphone in a laboratory model test. A small-scale concrete wall is constructed in a chamber, which is composed of a reinforced concrete plate and dry soil. A plastic bowl is then placed between the plate and soil to simulate a cavity behind the concrete structure. Leaky surface acoustic waves are generated by impacting the concrete plate using a hammer and are measured using a microphone. The measured signals are analyzed using natural frequencies, and cavity-free sections are evaluated. The test results show that the first natural frequency decreases at the cavity section due to the flexural vibration behavior of the plate. In addition, the amplitude corresponding to the first natural frequency decreases as the measurement location becomes farther from the cavity center and significantly decreases at the measurement locations near the rebars. This study demonstrates that a microphone may be useful to detect cavities behind concrete walls.

• Journal of Life Science
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• v.32 no.2
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• pp.79-85
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• 2022

Recently, many hangover cure products containing natural ingredients have been made available in the market that are effective for alcohol-related liver damage or for improved liver function. However, the cure for of liver damage or medication for improved liver function are different from hangover cure. Therefore, the efficacy hangover cure products needs to be verified. In this study, we investigated and compared the ameliorating effect of four commercially available hangover cure products on acute ethanol-induced hangover in Sprague - Dawley rats. The four samples were labeled as C, M, R, and S. The efficacy of the samples was evaluated based on the serum concentration and area under the curve (AUC) of blood ethanol and acetaldehyde concentrations to quantitatively assess the hangover cure effect. Ethanol administration to the rats significantly raised the serum alcohol and acetaldehyde levels. The Cmax reduction rates of ethanol for the samples C, M, R, and S were 5.9%, 3.1%, 8.4%, and 11.7%, and the AUC were 8.9%, 2.2%, 12.1%, and 19.6%, respectively, whereas the Cmax reduction rates of acetaldehyde were 14.2%, 15.2%, 28.2%, and 35.0%, and the AUC were 21.6%, 7.5%, 22.4%, and 29.9%, respectively. In conclusion, all samples showed a tendency to relieve hangover in the order of S, R, C, and M in terms of the ethanol concentration, but only sample S showed a statistically significant decrease in both Cmax and AUC for ethanol and acetaldehyde. These results suggest that an objective method for verifying the efficacy of hangover cure products is lacking.