• Journal of Korean Home Economics Education Association
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• v.30 no.3
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• pp.195-213
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• 2018

The purpose of this study is to verify the effect by developing and applying a new program for improvement of creative problem solving ability and collaborative ability. Development of a sewing practice program was performed through the ADDIE model. The subjects of the study were 1^st grade middle school students and the research plan of the study was pretest-posttest control group design. The study method was performed by mixing the quantitative and qualitative analysis methods. Results of this study are as follows. First, the students in the experimental group showed higher creative problem solving ability than the students in the control group, but the difference was not significant at the 5% significance level. Qualitative analysis results indicated that creative problem solving ability is closely related to learning experiences involving the 'generation of diverse ideas', 'rebirth of creative ideas', 'self-directed learning plan', 'active problem solving', 'immediate feedback'. Second, the students in the experimental group showed a significantly higher level of collaborative ability than the students in the control group. This demonstrated that the program developed in this study had an effect on fostering the collaborative ability of middle school students. It was found that collaborative ability is closely related to learning experiences involving 'forming a positive atmosphere', 'continuous interaction', and 'working together'.

• Health Policy and Management
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• v.31 no.4
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• pp.462-471
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• 2021

Background: The purpose of this study was to identify the association between participation in social activities and mortality rates for those aged 45 aged and older in Korea. Methods: In this study, the 1st to 6th Korea Longitude Study of Aging was used to analyze 10,217 people excluding missing values among middle and old age groups aged 45 or older. The scope of social activities was classified into "religious gatherings," "religious gatherings," "leisure/cultural/sports-related organizations," and "clubs/hometowns/religious associations," and analyzed using a chi-square test and Cox proportional risk model. Results: In the case of non-participating groups in religious activities, the mortality rate was 1.24 times higher (hazard ratio [HR], 1.24; p=0.000) than those of the participating group. The non-participating group of social gatherings had a 1.27 times higher mortality rate (HR, 1.27; p<0.0001) than the participating group. In addition, the mortality rate of non-participating groups related to leisure/cultural/sports was 1.79 times higher (HR, 1.79; p=0.000). The mortality rate of the group that did not participate in the alumni association/festival/folklore society was 1.51 times higher than that of the participating group (HR, 1.51; p<0.0001). As a result of correcting the control variable to analyze the relationship between the number of participants in social activities and the mortality rate, the mortality rate of the group participating in one or less social activities was 2.26 times higher (HR, 2.26; p<0.0001) compared to the four or more social activity participating groups, and the mortality rate of the 1-3 social activities was 1.64 times higher (HR, 1.64; p<0.0001). Conclusion: As a result of the study, it was found that participation in social activities of the middle-aged and elderly groups was effective in reducing mortality, and in particular, it was found that there was a strong relationship with mortality in less than one social activity group. Therefore, it is intended to provide an academic basis for lowering the mortality rate of the group in line with the continuous improvement of domestic social activity participation conditions, and through this, this study can be expected to serve as a policy and institutional basis for lowering the mortality rate of the group.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.3
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• pp.1-10
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• 2021

Harnesses are used in a variety of industries, such as rescue operations, medicine, and entertainment. However, conventional harnesses have problems as they are uncomfortable to wear and causes continuous pain. Therefore, in this study, the load and pressure applied to the body in the flying state when using a conventional harness were measured in real time and the distribution change was observed. Load and pressure were measured using a modified corset harness, a pressure sensor, and a human mannequin to measure the maximum and average pressure on the waist. As a result, it was confirmed that the load concentrated on the waist in the flying state was 104 N, and the pressure was applied to the left and right sides was 800 kPa or greater. The pressure distribution showed a pressure of 3-45 kPa in 73% in all measurable pressures. The results of the load and pressure distribution are presented as basic data for improving the wearability and reducing the discomfort of harnesses in the future, aid in the development of a harnesses that can minimize discomfort for various activities, and increase the concentration on experiential activities. In addition, using the CLO 3D program, which is a 3D virtual wearing system, a harness was put on a virtual model, and the compression level was checked and compared with the actual pressure distribution. As a result of comparing the measured pressure values in the flying state with the clothing pressure wearing the harness in the CLO 3D program, the total pressure value was found to be about 68% of the actual measured value. This helps develop a harness that can minimize discomfort during activities by predicting the load and pressure on the body by first applying new designs to a virtual wearing system during development. These new harness patterns can solve the problems of conventional harnesses.

• Journal of Environmental Science International
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• v.30 no.5
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• pp.413-424
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• 2021

In this study, we quantitatively analyze the effect of ocean emission sources on the simulated O₃ concentrations in South Korea using the community multi-scale air quality (CMAQ) model. To analyze changes in O₃ concentrations by ocean emissions, two different CMAQ simulations considering ocean emissions (OE case) and without considering ocean emissions (NE case) were conducted during the Korea-United States air quality (KORUS-AQ) campaign period (May-June 2016). The changes in the simulated O₃ concentrations due to the effect of ocean emissions (OE case-NE case) appeared mostly in the ocean areas (+1.201 ppbv). The effect of ocean emissions was positive during the daytime (+1.813 ppbv), but negative during the nighttime (-0.612 ppbv). Analysis using the integrated process rate (IPR) confirmed that the increase or decrease in O₃ concentration by ocean emissions was mainly due to chemical processes. Further analysis using the integrated reaction rate (IRR) showed that the daytime increase in O₃ concentration was mainly attributable to the increased O₃ production via O + O₂ + M → O₃ + M reaction as photolysis of NO₂ increased due to the added ocean emissions. The nighttime decrease in O₃ concentration was mainly due to the increased O₃ titration by NO (NO + O₃ → O₂ + NO₂) due to the increased NO emission. These results indicate that the changes in the concentration O₃ in the sea area by the effect of ocean emissions are mainly due to increased NO_x emissions. However, there could be a number of uncertainties in ocean emissions data used in this study, thus continuous comparative research using the most updated data will need to be carried out in the future.

• The Journal of Internal Korean Medicine
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• v.42 no.1
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• pp.11-24
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• 2021

Objective: Chronic reflux esophagitis (CRE), characterized by esophageal mucosa ulcer, is caused by continuous backflow of gastric acid and consequent inflammation due to unstable gastroesophageal sphincter. The aim of the present study was to clarify the effect of an Arecae Semen and Coptidis Rhizoma mixture (AC-mix) on CRE. Methods: CRE was surgically induced in SD rats with three experimental groups used: normal; CRE control; and CRE treatment (200 mg/kg AC-mix). Blood and esophageal tissue were collected after two weeks of drug administration. The anti-oxidant activity of the AC-mix was measured by total polyphenol and total flavonoid contents as well as by radical scavenging activity with protein levels evaluated using western blotting. Results: CRE damage to the esophageal mucosa was significantly reduced in the AC-mix group as compared with the controls, and administration of the AC-mix was seen to inhibit NF-κBp65 activity. Consequently, the inactivation of NF-κBp65 significantly inhibited inflammatory mediators such as COX-2 and iNOS. Moreover, the anti-oxidant enzyme HO-1 significantly increased through activation of the Nrf2-Keap1 pathway. Matrix metalloproteinase-2 (MMP-2), which can break down collagen from the basement membrane and extracellular matrix, was decreased following AC-mix treatment, and elevated levels of MMP-2 were regulated by its tissue inhibitor. Conclusions: These results show that AC-mix can alleviate esophageal mucosa ulcer though inhibition of the NF-κBp65 inflammatory pathway and enhancement of the anti-oxidant Nrf2-Keap1 pathway.

• Korean Journal of Remote Sensing
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• v.37 no.6_3
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• pp.1975-1984
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• 2021

Urban expansion results in raising the temperature in the city, which can cause social, economic and physical damage. In order to prevent the urban heat island and reduce the urban land surface temperature, it is important to quantify the cooling effect of the features of the urban space. Therefore, in order to understand the relationship between each object of land cover and the land surface temperature in Seoul, the land cover map was classified into 6 classes. And the correlation and multiple regression analysis between land surface temperature and the area of objects, perimeter/area, and normalized difference vegetation index was analyzed. As a result of the analysis, the normalized difference vegetation index showed a high correlation with the land surface temperature. Also, in multiple regression analysis, the normalized difference vegetation index exerted a higher influence on the land surface temperature prediction than other coefficients. However, the explanatory power of the derived models as a result of multiple regression analysis was low. In the future, if continuous monitoring is performed using high-resolution MIR Image from KOMPSAT-3A, it will be possible to improve the explanatory power of the model. By utilizing the relationship between such various land cover types considering vegetation vitality of green areas with that of land surface temperature within urban spaces for urban planning, it is expected to contribute in reducing the land surface temperature in urban spaces.

• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1255-1263
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• 2021

While it could become an alternative water resource, fog could undermine traffic safety and operational performance of infrastructures. To reduce such adverse impacts, it is necessary to have spatially continuous fog risk information. In this work, tree-based machine-learning models were developed in order to quantify fog risks with routine meteorological observations alone. The Extreme Gradient Boosting (XGB), Light Gradient Boosting (LGB), and Random Forests (RF) were chosen for the regional fog models using operational weather and visibility observations within the Jeollabuk-do province. Results showed that RF seemed to show the most robust performance to categorize between fog and non-fog situations during the training and evaluation period of 2017-2019. While the LGB performed better than in predicting fog occurrences than the others, its false alarm ratio was the highest (0.695) among the three models. The predictability of the three models considerably declined when applying them for an independent period of 2020, potentially due to the distinctively enhanced air quality in the year under the global lockdown. Nonetheless, even in 2020, the three models were all able to produce fog risk information consistent with the spatial variation of observed fog occurrences. This work suggests that the tree-based machine learning models could be used as tools to find locations with relatively high fog risks.

• International Area Studies Review
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• v.15 no.3
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• pp.263-283
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• 2011

As China has achieved continuous high growth, innovative housing system and rapid growth of housing finance for thirty years since its reforming and opening, Chinese real estate industry has developed rapidly, investment in real estate has increased remarkably and price of real estate has increased continuously. In particular, as China joined WTO in 2001, overseas companies have expanded investment in Chinese real estate market with chances of potential profit. Recently, management of foreign capital real estate companies has expanded from housing to office buildings and luxury shops. Besides, management has expanded from real estate development to various tasks such as management, brokerage service, lease management and financial investment. In order to measure relationship between FDI in Chinese real estate and Chinese housing price, this document utilizes not only various data such as housing price, FDI to real estate, domestic loan of real estate, interest rate and exchange rate in 35 major cities across China but also previous researches to set an empirical analysis model and analyze effects of foreigners' direct investment in Chinese real estate on Chinese housing price.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.338-352
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• 2019

This study was empirically intended to determine obstacle factors of the global start-up promotion for the international inroad of global start-up companies. The statistical analysis of reliability and validity was conducted through the AMOS structural equation model after surveying 300 companies over 5 years old into start-up in metropolitan cities across the country. The findings are as follows. The global start-up growth had a very close relationship with capital, product development period, quality and human resources. And capital as a start-up obstacle factor was insignificant, but development period, quality and human resources had a close relationship with industrial competitiveness. Even in the mediating effect of start-up obstacle factors on industrial competitiveness, capital was rejected, while quality, development period and human resources were adopted, having a positive mediating effect. These results demonstrate that capital is not a big obstacle to the management because of the continuous support of the government due to the nature of start-up companies, but growth is in a remote future as long as there is no independent product competitiveness to maintain the quality of products at a certain level and support of professional workforce to develop and commercialize them.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.319-325
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• 2018

The use of 3D printing (Additive Manufacturing) technology has expanded from initial model production to the mass production of parts in the industrial field based on the continuous research and development of materials and process technology. As a representative polymer material for 3D printing, the polyamide-based material, which is one of the high-strength engineering plastics, is used mainly for manufacturing parts for automobiles because of its light weight and durability. In this study, the specimens were fabricated using Selective Laser Sintering, which has excellent mechanical properties, and the flexural characteristics were analyzed according to the temperature of the two types of polyamide 12 and glass bead reinforced PA12 materials. The test specimens were prepared in the directions of $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$ based on the work platform, and then subjected to a flexural test in three test temperature environments of $-25^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$. As a result, PA12 had the maximum flexural strength in the direction of $90^{\circ}$ at $-25^{\circ}C$ and $0^{\circ}$ at $25^{\circ}C$ and $60^{\circ}C$. The glass bead-reinforced PA12 exhibited maximum flexural strength values at all test temperatures in the $0^{\circ}$ fabrication direction. The tendency of the flexural strength changes of the two materials was different due to the influence of the plane direction of the lamination layer depending on the type of stress generated in the bending test.