• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.527-536
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• 2022

The purpose of this study is to predict changing traffic environments and related economic effects by reflecting the changed KTDB and socio-economic indicators pertaining to Mulgeum station, a general railway stop, when it is confirmed as a KTX stop. To analyze the data of this study, socioeconomic indicators and the general status of transportation facility operations were investigated with reference to related statistical data, centered on the country overall and on Yangsan city in particular. In addition, we investigated and referenced the railroad facility construction plan and train operation plan, which are national high-level plans related to land development and transportation network construction. Currently, there are only ITX trains (4 times/day) and Mugunghwa trains (29 times/day) that stop at Mulgeum station in Yangsan, meaning that passengers cannot use KTX trains in the Yangsan area. In particular, the need for a KTX stop at Mulgeum station has been continuously raised because train users in the Yangsan area have inconvenient transportation in that they must travel 40 minutes to Ulsan station or 30 minutes to Gupo station to use the KTX. As a result of analyzing railroad transportation demand that will change in the future as the KTX stop at Mulgeum station is confirmed, the number of passengers boarding and arriving at Mulgeum station is predicted to be 1,674 passengers/day by 2025. In addition, the numbers of train passengers that are converted from Ulsan and Gupo stations due to the stop at Mulgeum station are predicted to be 594 passengers/day boarding and 562 passengers/day arriving by 2025. In the future, if Yangsan citizens use the KTX Mulgeum station, the access time to Mulgeum station can be shortened to 22 minutes from 65 minutes, and it is predicted that the inconvenience of transferring between railroads will be resolved, with the waiting time for transfers reduced by up to a maximum of 40 minutes. Therefore, the economic effect of creating a KTX stop at Mulgeum station was analyzed to be B/C=1.823 when general railroad operating costs are not taken into account and B/C=2.127 when general railroad operating costs are considered. In conclusion, when using KTX trains to visit the Seoul Metropolitan Area, it takes 2 hours and 43 minutes to use Mulgeum station without using Ulsan station or Gupo station, which is considered to be very effective for reducing travel times and improving the economic feasibility of this development; it is also expected that Yangsan city will be able to improve accessibility and mobility to the Seoul Metropolitan Area by breaking free from the disgrace of being a remote location given its link to KTX in the future.

• Korean Journal of Remote Sensing
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• v.38 no.6_3
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• pp.1817-1826
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• 2022

After the hydrogen fluoride leak in Gumi in 2012, the government has been systemizing the disaster management system, such as responding to and managing chemical accidents. In particular, the Ministry of the Interior and Safety (MOIS) is in charge of evacuation of residents following chemical accidents based on the Framework Act on Management of Disaster and Safety. In this study, an application plan was presented to support and utilize the decision-making support for evacuation of residents after a chemical accident using the chemical accident investigation equipment of the National Disaster Management Research Institute (NDMI). In the equipment operation system for scientific information collection due to chemical accidents, the roles and purpose of use of long/short distance measurement equipment were presented according to regular and emergency situations. Using the data acquired through long/short distance measurement equipment, it can be used as basic data for resident evacuation decision-making by monitoring whether chemicals are detected in an emergency and managing data on detected substances by company in a regular situation. As a result of measuring chemical substances in order to verify on-site usability by equipment only for the regular operation system, it was confirmed that real-time detection of chemical substances is possible with long distance measuring equipment. In addition, it was confirmed that it was necessary to check the measurable distance and range of the equipment in the future. In the case of short distance measurement equipment, hydrocarbon-based substances were mainly detected, and it was confirmed that it was measured at a higher level in Ulsan-Mipo National Industrial Complex than in Onsan National Industrial Complex. It is expected that it can be used as basic data to support decision-making in the event of chemical accidents through continuous data construction in the future.

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1723-1735
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• 2022

Landslides are one of the most prevalent natural disasters, threating both humans and property. Also landslides can cause damage at the national level, so effective prediction and prevention are essential. Research to produce a landslide susceptibility map with high accuracy is steadily being conducted, and various models have been applied to landslide susceptibility analysis. Pixel-based machine learning models such as frequency ratio models, logistic regression models, ensembles models, and Artificial Neural Networks have been mainly applied. Recent studies have shown that the kernel-based convolutional neural network (CNN) technique is effective and that the spatial characteristics of input data have a significant effect on the accuracy of landslide susceptibility mapping. For this reason, the purpose of this study is to analyze landslide vulnerability using a pixel-based deep neural network model and a patch-based convolutional neural network model. The research area was set up in Gangwon-do, including Inje, Gangneung, and Pyeongchang, where landslides occurred frequently and damaged. Landslide-related factors include slope, curvature, stream power index (SPI), topographic wetness index (TWI), topographic position index (TPI), timber diameter, timber age, lithology, land use, soil depth, soil parent material, lineament density, fault density, normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used. Landslide-related factors were built into a spatial database through data preprocessing, and landslide susceptibility map was predicted using deep neural network (DNN) and CNN models. The model and landslide susceptibility map were verified through average precision (AP) and root mean square errors (RMSE), and as a result of the verification, the patch-based CNN model showed 3.4% improved performance compared to the pixel-based DNN model. The results of this study can be used to predict landslides and are expected to serve as a scientific basis for establishing land use policies and landslide management policies.

• 한국노년학
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• v.40 no.4
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• pp.707-727
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• 2020

This study aims to empirically analyze the role that perception of the probability of lonely death among the elderly people living alone plays in the relationship between perceived social support and preference for institutional care based on Andersen's expanded Behavioral Model (2002). The subjects (n=676) of this study were the elderly people living alone, extracted from the "2018 Seoul Aging Survey." With "perceived social support" as an independent variable, "preference for institutional care" as a dependent variable, and "perception of the probability of lonely death" as a mediator variable, we conducted a Binary Logistic Regression to follow the three steps of analyzing mediation effect, as suggested by Baron and Kenny (1986). The results showed that perceived social support has a negative effect on the preference for institutional care and perception of the probability of lonely death among the elderly people living alone; at the same time, perception of the probability of lonely death was found to have a positive effect on their preference for institutional care. Lastly, perception of the probability of lonely death was found to partially mediate the effect of perceived social support among the elderly people living alone in terms of their preference for institutional care. Based on these findings, the practical implications of this study can be summarized as follows. First, various programs and support should be provided to the elderly people living alone in order to enhance the level of perceived social support, a factor that has been confirmed to increase preference for institutional care among the elderly people living alone. Second, as the perception of the probability of lonely death was confirmed to be a psychosocial factor of the preference for institutional care, we need to promote education and support for older people living alone to prepare them for lonely death. These efforts are expected to form a foundations for implementing a community-based integrated care system, "Aging in Place," which is the policy direction required for older people care.

• Journal of Korea Port Economic Association
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• v.38 no.1
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• pp.101-111
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• 2022

As Asia's leading advanced country, Korea has an absolute advantage over foreign trade routes and maritime economies over inland countries. Following the change in social background, the original port area is for various reasons, and some ills are gradually revealing people's private interests. Due to this, it is the economic interest and future development space of the marine industry cluster in the port area that are directly affected and damaged. This study studied the relationship between marine industry clusters and port urban regeneration. It is intended to present the necessity and importance of activating the marine industry cluster through port urban regeneration while analyzing the regenerative design from the quantitative analysis angle. Therefore, first of all, the theoretical backgrounds were considered, and the cases of port cities that did well worldwide were analyzed according to the current status of the northern port of Busan, the research target site, through analysis. In addition, in order to increase the reliability of this study, the data of marine industry clusters and port city regeneration were reviewed using empirical analysis. Looking at the results of this study's case study and empirical analysis, it is a relationship that actually improved and interacted between the marine industry cluster and the port city regeneration. Through the study, it is expected that the Busan North Port Redevelopment Project will be promoted at the design, environmental, and economic level, and at the same time, it will be able to enhance its status as a marine city in Busan. The results show that, no matter which country or port city, the development of economy, society, culture and will inevitably promote the vigorous development of the marine industrial cluster, also, the port area development to a certain degree. will naturally the physical conditions of regional development obstacle through the port city of regeneration. This promotion will overcome.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.161-173
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• 2021

The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.

• Journal of Christian Education in Korea
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• v.71
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• pp.277-303
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• 2022

The COVID-19 Pandemic, which began in 2020, has led to many changes in the Korean church. It created a situation in which not only the change and form of worship time, but also the definition, direction, and philosophy of ministry had to be re-established. In the early days of COVID-19 Pandemic, the Korean church recognized this as a crisis, but gradually regarded these as opportunities and tried to produce positive results. The Department of Education has also undergone many changes, especially in its summer ministry, and is expected to have undergone more dramatic changes in form, location and method than in any other church event or service. However, no accurate data on this has been collected. Accordingly, Mirae with Dreams (CEO: Pastor Kim Eun-ho), a corporation established by the Oryun Church for the next generation of ministry, conducted a survey on the summer ministry of the Korean church, which has been registered as a future member with dreams every year since 2020 when the COVID-19 fan dummy began. A similar survey was conducted in 2022 following 2021, and 260 churches responded, and the results are as follows. In 2022, the summer ministry of the Ministry of Education of the Korean Church returned to the form before the COVID-19 Pandemic. Unlike 2021, when many of them were held online, more than 81 percent said they had conducted summer camps offline, and 31 percent also conducted or attended outdoor camps. In terms of the importance of roles, when online was also the main focus, parents and teachers were equally viewed or emphasized, while in this summer's survey, 90 percent of respondents said that the role of teachers in charge or department was important. Summer events were mainly summer Bible schools and retreats, but 25% of all respondents said they conducted missionary work and evangelism at home and abroad. Compared to 2021, participation in summer camps has increased in all departments, including infant and kindergarten, elementary and middle school, and especially in infant and middle school. While preparing for the summer camp, most of the respondents said that the focus was on content and topics, and the main focus was on children's accessibility compared to 2021. As a result of synthesizing the description of the reason for the respondents who could not conduct the summer camp, about 40% said they could not conduct the summer camp due to a lack of volunteers. This is more than 30% who pointed out COVID-19 as the cause, which can be seen as an urgent problem to be solved at the Korean church and denomination level. In addition, this paper also mentioned detailed changes in each question, referring to the changes in summer camps from 2020 to 2022.

• Journal of Life Science
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• v.32 no.11
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• pp.865-871
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• 2022

Tenebrio molitor larvae is well known as edible insect. Then, although it has been widely studied that Tenebrio molitor larvae has various bioactive functions such as antioxidant, anti-wrinkle, and anticancer. Nevertheless, antioxidant effects of Tenebrio molitor larvae water extract (TMH) has not been well described in Adult Retina Pigment Epithelial cell line (ARPE-19). In this study, we demonstrated that antioxidant effects of TMH against H₂O₂-induced oxidative stress in ARPE-19. Thus, we selected for our studies and performed a series of dose-response assay to determine the working concentration that lead to a consistent and high degree of cytotoxicity, which we defined as the level of H₂O₂ that killed 40% of the ARPE-19 cells. ARPE-19 cells were pre-treated with various concentrations of TMH (0.1 up to 2 mg/ml) before exposure to 300 µM H₂O₂. As we expected, TMH effectively prevented ARPE-19 cells from 300 µM H₂O₂-induced cell death in a dose-dependent manner. Furthermore, TMH inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Overall, the inhibitory effects of TMH on H₂O₂-induced apoptosis and oxidative stress were associated with the protection cleaved caspase-3, Bax, Bcl-2, and HO-1. The TMH suppressed H₂O₂-induced cell membrane leakage and oxidative stress in ARPE-19 cells. Thus, these results suggest that the TMH plays an important role in antioxidant effect in ARPE-19.

• Journal of the Korean Society of Radiology
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• v.16 no.1
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• pp.35-43
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• 2022

In this study, a survey was conducted and analyzed to find out the satisfaction of online classes among students enrolled in the radiology department of a university located in Busan city. As a result, in terms of satisfaction with online classes, male scores were higher, but there was no statistically significant difference. In the interdisciplinary system, the satisfaction score of the students enrolled in Bachelor's degree was high, and there was a statistically significant difference except for the satisfaction of learning participation (p<0.001, p<0.05). For class satisfaction by grade level, Senior had higher scores, and there were statistically significant differences except for learning participation satisfaction (p<0.001, p<0.01, p<0.05). In the satisfaction survey according to the number of lectures, the scores of the students who took 4-7 lectures were found to be high except for the satisfaction of learning participation, and there was a statistically significant difference (p<0.01, p<0.05). In the method of communication with the instructor, students who used e-mail showed high scores, and there was a statistically significant difference in lecture satisfaction (p<0.05). In the correlation analysis between sub-variables for online classes, statistically significant correlations were established in all areas. Most of the students preferred class methods such as recorded classes and classes using external content such as YouTube, and when asked about the merits of online classes, many students answered that the advantages of online classes were repetitive classes and no restrictions on time and place. When asked about the shortcomings of online classes, many students answered that it was a lack of concentration and lack of communication with the instructor. This study was conducted to provide basic data to improve the satisfaction of online classes that will increase in the future. Therefore, based on the results of this study, it is expected that more quality online classes will be produced so that students' satisfaction with online classes can be improved.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.347-355
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• 2022

The safety valve (PSV) is a safety device that automatically releases a spring when the pressure generated by various causes reaches the set pressure, and is restored to a normal state when the pressure falls below a certain level. Periodic inspection and monitoring of safety valves are essential so that they can operate normally in abnormal conditions such as pressure rise. However, as the current safety inspection is performed only at a set period, it is difficult to ensure the safety of normal operation. Therefore, evaluation items were developed by finding failure modes and causative factors of safety valves required for safety management. In addition, it is intended to provide decision-making information for securing safety by deriving the priority of items. To this end, a Delphi survey was conducted three times to derive evaluation factors that were judged to be important in relation to the Failure Mode Cause Factor (FMCFs) of the safety valve (PSV) targeting 15 experts. As a result, 6 failure modes of the safety valve and 22 evaluation factors of its sub-factors were selected. In order to analyze the priorities of the evaluation factors selected in this way, the hierarchical structure was schematized, and the hierarchical decision-making method (AHP) was applied to the priority calculation. As a result of the analysis, the failure mode priorities of FMCFs were 'Leakage' (0.226), 'Fail to open' (0.201), 'Fail to relieve req'd capacity' (0.152), 'Open above set pressure' (0.149), 'Spuriously' 'open' (0.146) and 'Stuck open' (0.127) were confirmed in the order. The lower priority of FMCFs is 'PSV component rupture' (0.109), 'Fail to PSV size calculation' (0.068), 'PSV Spring aging' (0.065), 'Erratic opening' (0.059), 'Damage caused by improper installation and handling' (0.058), 'Fail to spring' (0.053), etc. were checked in the order. It is expected that through efficient management of FMCFs that have been prioritized, it will be possible to identify vulnerabilities of safety valves and contribute to improving safety.