• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.285-294
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• 2022

In order to accurately calculate greenhouse gas emissions in the agricultural field, Korea has been developing national-specific emission factors through direct measurement of gas fluxes using the closed-chamber method. In the rice paddy, only national-specific emission factors for methane (CH₄) have been developed. It is thus necessary to develop those for nitrous oxide (N₂O) affected by the application of nitrogen fertilizer. However, since the concentration of N₂O emission from rice cultivation is very low, the QA/QC methods such as method detection and practical quantification limits are important. In this study, N₂O emission from a rice paddy was evaluated affected by the amount of nitrogen fertilizer, by taking into account both method detection and practical quantification limits for N₂O concentration. The N₂O emission from a rice paddy soils affected by the nitrogen fertilizer application was estimated in the following order. The method detection limit (MDL) of N₂O concentration was calculated at 95% confidence level based on the pooled standard deviation of concentration data sets using a standard gas with 98 nmol mol^-1 N₂O 10 times for 3 days. The practical quantification limit (PQL) of the N₂O concentration is estimated by multiplying 10 to the pooled standard deviation. For the N₂O flux data measured during the rice cultivation period in 2021, the MDL and PQL of N₂O concentration were 18 nmol mol^-1 and 87 nmol mol^-1, respectively. The measured values above the PQL were merely about 12% of the total data. The cumulative N₂O emission estimated based on the MDL and PQL was higher than the cumulative emission without nitrogen fertilizer application. This research would contribute to improving the reliability in quantification of the N₂O flux data for accurate estimates of greenhouse gas emissions and uncertainties.

• Journal of Internet of Things and Convergence
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• v.8 no.3
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• pp.1-10
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• 2022

The purpose of this study was to investigate how the characteristics of mobile-based financial platforms have an impact on the intention to use loan service users. In addition, it was attempted to investigate whether usefulness and ease of use had a mediating effect in the relationship between each characteristic of the mobile financial platform on the intention to use the loan service. Data collection was conducted from March 1 to April 30, 2022, and 200 people participated in the study. Analysis methods were frequency analysis, exploratory factor analysis, reliability analysis, correlation analysis, hierarchical multiple regression analysis, and three-step mediation regression analysis. The research results are as follows. First, the influence of user factors, technical factors, and environmental factors of a financial platform on the intention to use a mobile loan service was found to be ubiquity in user factors, reliability in technical factors, and facilitation conditions in environmental factors. Second, in the relationship between convenience and intention to use user factors, usefulness had a completely mediating effect. Third, in the relationship between reliability of technical factors and intention to use, usefulness showed a partial mediating effect. Fourth, in the relationship between the social impact of environmental factors and facilitation conditions and intention to use, the usefulness showed a partial mediating effect. Fifth, ease of use showed a completely mediating effect in the relationship between convenience and intention of use of user factors. Sixth, in the relationship between reliability of technical factors and intention to use, ease of use showed a partial mediating effect. Seventh, in the relationship between the social impact of environmental factors and intention to use, ease of use showed a partial mediating effect, and in the relationship between facilitation conditions and intention to use, ease of use showed a fully mediating effect. Through this study, we tried to present basic data on the determinants of the user's acceptable intention to use the mobile loan service.

• Science of Emotion and Sensibility
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• v.25 no.1
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• pp.41-54
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• 2022

The purpose of this study was to propose a "user experience (UX)-centered product development process" so that the product design development process using the service design process can be systematized and used in practice. In a situation in which usability research on office phones is lacking compared to general home phones, this study expands to a product-based service design point of view rather than simple product development, intending to research ways to provide user experience value through office phone design in smart office. This study focused on extracting UX-centered user needs using the service design process and developing product design that realizes user experience value. In particular, the service design process was applied to systematically extract user needs and experience value elements in the product development process and to discover ideas that were converged with product-based services. For this purpose, the "Double Diamond Design Process Model," which is widely used in the service design field, was adopted. In addition, a product design development process was established so that usability improvement plans, user experience value elements, and product-service connected ideas could be extracted through a work-flow in which real users and people from various fields participate. Based on the double diamond design process, in the "Discover" information collection stage, design trends were identified mainly in the office phone markets. In the "Define" analysis and extraction stage, user needs were analyzed through user observation, interview, and usability survey, and design requirements and user experience issues were extracted. Persona was set through user type analysis, and user scenarios were presented. In the "Develop" development stage, ideation workshops and concept renderings were conducted to embody the design, and people from various fields within the company participated to set the design direction reflecting design preference and usability improvement plans. In the "Deliver" improvement/prototype development/evaluation stage, a working mock-up of a design prototype was produced and design and usability evaluation were conducted through consultation with external design experts. It is meaningful that it established a "UX-centered product development process" model that converged with the existing product design development process and service design process. Ultimately, service design-based product design development process was presented so that I Corp.'s products could realize user experience value through service convergence.

• 지역과문화
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• v.7 no.2
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• pp.173-202
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• 2020

This study aims to enhance the family-friendliness of the region by examining the relationship between family relations and the community environment, and objectively comparing the local environment surrounding the family. To this end, we reviewed the areas of socio-cultural and economic sectors that affect the family relationship satisfaction, and in particular, analyzed the trend of changes in regional index by utilizing the Korean Family Happiness Composite Index (KFHCI) developed as a community indicators. This index utilizes community indicators published in the National Statistical Portal's "e-Region indicators," and these variables are related to family relationship satisfaction. Therefore, this study compared the seven areas of the Family Happiness Composite Index (Population Family, Health Culture, Education, Income Consumption, Employment Labor, Housing Transportation, Environment and Social Integration) by region, and examined the trends for 10 years. According to the study, the average score of KFHCI's entire region was rising from 2008 to 2018. Overall, the community environment that affects family relationship satisfaction is also improving. The regions belonging to the upper level were Jeonnam, Gangwon, Chungnam, Jeonbuk, and Gyeongbuk. Areas belonging to the lower level are Seoul, Busan, Daegu, Incheon, and Gwangju. In almost sectors, the lower-level regions did not have sufficient physical infrastructure compared to population density and over-density, and improved little by little, but not enough to reflect the needs of local people and improve the quality of life. In the future, we should develop more regular and complementary indicators to develop customized policies for each region that can improve the quality of family relationships. It will also be necessary to study the impact of each index field when a socioeconomic crisis occurs due to social disasters, and try to change indicators

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.327-339
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• 2022

The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m³/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m³/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m³/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.

• Journal of Korean Home Economics Education Association
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• v.33 no.4
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• pp.139-157
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• 2021

The purpose of this study is to derive implications for Korean home economics curriculum to emphasize consumer competency of adolescents by analyzing the content components of consumer competency presented in 'consumer life' area of middle school home economics curriculum of 3 states in the U.S. The analysis results and implications are summarized as follows: First, the U.S. home economics curriculum is composed of various contents, including credit management, savings/investment/ insurance, taxes, and financial situation, and financial decision-making, to improve adolescent's understanding of finance. In the next revision of Korean curriculum, for financial stability in prolonged life after retirement, it is would be necessary to include contents on basic financial knowledge and technology for financial information utilization so that students can establish financial plans for different life stages in consideration of various variables such as changes in economic environment, etc. Second, the U.S. home economics curriculum was developed to help students make better purchase decisions by applying economic concepts such as prices and interest rates, economic trends and the impact of demand and supply, purchase methods and contract conditions, etc. However, Korean home economics curriculum only focus on purchase plan and purchase decision-making process. It would be necessary to foster consumer transaction competency by introducing economic concepts suitable middle school level. Third, to emphasize "consumer civic competency", Ohio was focusing on "claim of consumer rights" and Wisconsin was focusing on the "acceptance of consumer responsibility." In order to enhance adolescent's consumer civic competency, it would be necessary for Korean curriculum to balance the claim of right and the acceptance of consumer responsibility in the following term, and to emphasize the contents on consumer policies, laws and consumer advocacy to create a consumer environment where consumer sovereignty is realized.

• Korean Journal of Cognitive Science
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• v.33 no.2
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• pp.109-133
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• 2022

Episodic memory consists of a core event and the associated contexts. Although the role of the hippocampus and its neighboring regions in contextual representations during encoding has become increasingly evident, it remains unclear how these regions handle various context-specific information other than spatio-temporal contexts. Using high-resolution functional MRI, we explored the patterns of the medial temporal lobe (MTL) and cortical regions' involvement during the encoding of various types of contextual information (i.e., journalism principle 5W1H): "Who did it?," "Why did it happen?," "What happened?," "When did it happen?," "Where did it happen?," and "How did it happen?" Participants answered six different contextual questions while looking at simple experimental events consisting of two faces with one object on the screen. The MTL was divided to sub-regions by hierarchical clustering from resting-state data. General linear model analyses revealed a stronger activation of MTL sub-regions, the prefrontal lobe (PFC), and the inferior parietal lobule (IPL) during social (Who), behavioral (How), and intentional (Why) contextual processing when compared with spatio-temporal (Where/When) contextual processing. To further investigate the functional networks involved in contextual encoding dissociation, a multivariate pattern analysis was conducted with features selected as the task-based connectivity links between the hippocampal subfields and PFC/IPL. Each social, behavioral, and intentional contextual processing was individually and successfully classified from spatio-temporal contextual processing, respectively. Thus, specific contexts in episodic memory, namely social, behavior, and intention, involve distinct functional connectivity patterns that are distinct from those for spatio-temporal contextual memory.

• Economic and Environmental Geology
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• v.56 no.2
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• pp.167-183
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• 2023

Gases originated from the final SNF (spent nuclear fuel) disposal site are very mobile in the barrier and they may also affect the migration of radioactive nuclides generated from the SNF. Mechanisms of gas-nuclide migration in the multi-barrier and their influences on the safety of the disposal site should be understood before the construction of the final SNF disposal site. However, researches related to gas-nuclide coupled movement in the multi-barrier medium have been very little both at home and abroad. In this study, properties of gas generation and migration in the SNF disposal environment were reviewed through previous researches and their main mechanisms were summarized on the hydrogeological evolution stage of the SNF disposal site. Gas generation in the SNF disposal site was categorized into five origins such as the continuous nuclear fission of the SNS, the Cu-canister corrosion, the oxidation-reduction reaction, the microbial activity, and the inflow from the natural barriers. Migration scenarios of gas in porous medium of the multi-barrier in the SNF repository site were investigated through reviews for previous studies and several gas migration types including ① the free gas phase flow including visco-capillary two-phase flow, ② the advection and diffusion of dissolved gas in pore water, ③ dilatant two-phase flow, and ④ tensile fracture flow, were presented. Reviewed results in this study can support information to design the further research for the gas-nuclide migration in the repository site and to evaluate the safety of the Korean SNF disposal site in view points of gas migration in the multi-barrier.

• Journal of the Korean earth science society
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• v.43 no.6
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• pp.691-711
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• 2022

The state-of-the-art Earth system model as a virtual Earth is required for studies of current and future climate change or climate crises. This complex numerical model can account for almost all human activities and natural phenomena affecting the atmosphere of Earth. The Unified Model (UM) from the United Kingdom Meteorological Office (UK Met Office) is among the best Earth system models as a scientific tool for studying the atmosphere. However, owing to the expansive numerical integration cost and substantial output size required to maintain the UM, individual research groups have had to rely only on supercomputers. The limitations of computer resources, especially the computer environment being blocked from outside network connections, reduce the efficiency and effectiveness of conducting research using the model, as well as improving the component codes. Therefore, this study has presented detailed guidance for installing a new version of the UM on high-performance parallel computers (Linux clusters) owned by individual researchers, which would help researchers to easily work with the UM. The numerical integration performance of the UM on Linux clusters was also evaluated for two different model resolutions, namely N96L85 (1.875° ×1.25° with 85 vertical levels up to 85 km) and N48L70 (3.75° ×2.5° with 70 vertical levels up to 80 km). The one-month integration times using 256 cores for the AMIP and CMIP simulations of N96L85 resolution were 169 and 205 min, respectively. The one-month integration time for an N48L70 AMIP run using 252 cores was 33 min. Simulated results on 2-m surface temperature and precipitation intensity were compared with ERA5 re-analysis data. The spatial distributions of the simulated results were qualitatively compared to those of ERA5 in terms of spatial distribution, despite the quantitative differences caused by different resolutions and atmosphere-ocean coupling. In conclusion, this study has confirmed that UM can be successfully installed and used in high-performance Linux clusters.

• Journal of Life Science
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• v.33 no.4
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• pp.315-324
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• 2023

The underlying action of policosanol in lowering cholesterol level has not yet been clearly elucidated. Several recent studies have suggested that sterol regulatory element-binding proteins (SREBP)-1c play a role in the regulation of cholesterol synthesis via the fatty acid synthesis pathway. To date, no study has evaluated the effects of policosanol on SREBP-1c-mediated fatty acid synthesis. Therefore, this study aimed to investigate whether the SREBP-1c-mediated fatty acid biosynthetic pathway is associated with the cholesterol-lowering effects of policosanol. Seven-week-old C57BL/6 male mice were randomly divided into 7 groups (n=7 per group) and treated for 8 weeks as follows: 1) normal diet (normal control), 2) high-fat diet (HFD), 3) HFD+ethanol (Pol-0), 4) HFD+policosanol 1 mg/kg (Pol-1), 5) HFD+policosanol 2 mg/kg (Pol-2), 6) HFD+policosanol 4 mg/kg (Pol-4), and 7) HFD+simvastatin 50 ㎍/kg (positive control). Policosanol and simvastatin were administered at the same time every day while maintaining the HFD. Body weight and food intake were measured weekly for 8 weeks. After 8 weeks, serum cholesterol levels were measured, histological analysis was carried out, and the expressions of SREBP-1c and fatty acid synthase (FAS) in the liver tissues were examined. Policosanol reduced body weight and the amount of food intake in a dose-dependent manner. Serum cholesterol levels were significantly lowered in the Pol-1 and Pol-4 groups. The expression of SREBP-1c and FAS was also significantly decreased in the Pol-4 group. These results suggest that the cholesterol-lowering effects of policosanol can occur due to the inhibition of the expression of SREBP-1c and FAS.