• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.1-8
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• 2019

Identifying behavioral errors of seafarers that have led to marine accidents is a basis for research into prevention or mitigation of marine accidents. The purpose of this study is to estimate the optimal probability distribution function needed to model behavioral errors of crew members into three behaviors (i.e., Skill-, Rule-, Knowledge-based). Through use of behavioral data obtained from previous accidents, we estimated the optimal probability distribution function for the three behavioral errors and verified the significance between the probability values derived from the probability distribution function. Maximum Likelihood Estimation (MLE) was applied to the probability distribution function estimation and variance analysis (ANOVA) used for the significance test. The obtained experimental results show that the probability distribution function with the smallest error can be estimated for each of the three behavioral errors for eight types of marine accidents. The statistical significance of the three behavioral errors for eight types of marine accidents calculated using the probability distribution function was observed. In addition, behavioral errors were also found to significantly affect marine accidents. The results of this study can be applied to predicting marine accidents caused by behavioral errors.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.247-258
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• 2021

The purpose of this study is to investigate whether character education program using Youtube PSAs affect psychological and social maturity of pre-service teachers. For data collections, questionnaires and semi-structured interview are used by 23 sophomores majoring in teacher education. The results are as follows. First, the participants showed highly significant improvement on each of two maturities as well as entire psychological and social maturity. Second, the score of factors of social maturity was lower than that of those of psycho maturity. it could be estimated that college students live in nuclear family and individualization is valued more. Third, while pre-test scores of entire psycho-social maturity are not statistically significant, post-test scores of each of psycho-social maturity indicated statistical significance. In particular, unlike pre-test, there is a strong positive correlation in post-test due to mutually positive impact of two factors. Fourth, there was no statistically significant sex difference. Lastly, according to the result of interview, participants had strong views on the effects of personality education associated with use of Youtube PSAs on motivation and focus in class, caring for others, and leading to positive behaviors.

• Journal of the Korean GEO-environmental Society
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• v.12 no.1
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• pp.61-70
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• 2011

The impact protection system consists of an arrangement of circular sheet pile cofferdams-denoted dolphin structuredeeply embedded in the seabed, filled with crushed rock and closed at the top with a robust concrete cap. Centrifuge model tests were performed to investigation the behaviors of dolphins in this study. Total 7 quasi-model tests and 11 dynamic model tests were performed. The main experimental results can be summarized as follows. Firstly, The experimental force-displacement results for quasi-static tests show a limited influence on the initial stiffness of the structure from the change in fill density and the related change in the stiffness of the fill. And by comparing the dissipation at the same dolphin displacement it was found that the denser fill increase the dissipation by 16% for the 20m dolphin and by 23% for the 30m dolphin. The larger sensitivity for the large dolphin is explained by a larger contribution to the dissipation from strain in the fill. In low level impacts the dynamic force-response is up to 26~58% larger than the quasi-static and the dissipation response is showed larger in small displacement. Hence, it is concluded conservative to use the quasi-static response characteristics in the approximation of the response, and it is further concluded that the dolphin resistance to low level impacts is demonstrated to be equivalent and even superior to the high level impacts.

• Journal of the Korean Regional Science Association
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• v.37 no.1
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• pp.29-44
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• 2021

Particulate matter(PM) is one of the leading causes of lung cancer. Recognizing its considerable risk to human health, people change their behaviors when a concentration level of PM is high. The impact of particulate matter on urban activities may vary depending on the lasting days of PM and PM matter alerts. In addition, the level of averting behavior may vary depending on the types and physical characteristics of urban activities and the degree of vulnerability to PM among people. Although the way people respond to PM may vary depending on these various factors, previous research evidence on this is very insufficient. Therefore, this study multilaterally analyzed the impact of PM on the urban activities in Jongno-gu, one of the CBD areas of Seoul. For this, we linked SKT's mobile phone signal data to land use data to extract the daily number of active people by urban activity types and ages. According to multiple regression analysis, the averting behavior varies depending on the type of urban activity, the physical characteristics of the place of activity(inside and outdoor), the lasting days of PM, PM alerts and the age of people. The results of this study can be used as basic data to policy makers who establish policies for adapting to air pollution policies by providing various effects of PM on the urban activities.

• Journal of Korean Library and Information Science Society
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• v.52 no.4
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• pp.277-307
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• 2021

This study aims to understand the current status of science-related channels on YouTube provided by government-funded research institutes and investigate user experiences and behaviors of using the services. We examined the number of subscribers, view counts, and video contents of 26 YouTube channels from the government-funded research institutes. We also designed a user study with the uses and gratifications theory and conducted a semi-structured interview. By grouping videos into five categories: Public Relations, Lectures, Entertainment, Vlogs, and Q&A, most videos were about research projects or institutional promotions. User motivation for using the YouTube channel was to acquire scientific knowledge and information. Users thought that YouTube channels could provide reliable information and satisfy their intellectual curiosity. But they criticized that most videos were uninteresting, and the lack of promotions of the channels made others hesitant to sign up and watch. Findings from this study could help fully understand the current status of the government-funded research institute's YouTube channel and be used as resources for the government's planning and development of various YouTube services.

• Korean Journal of Community Nutrition
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• v.27 no.1
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• pp.27-35
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• 2022

Objectives: The purposes of this study were to compare the degree of sodium reduction practice and estimate sodium intake by salty food preference. Methods: Sodium reduction practices, salty food preferences and estimated sodium intake were surveyed for restaurant owners (n = 80), employees (n = 82) and customers (n = 727) at the restaurants participating in the sodium reduction project in Daegu, Korea. Estimated sodium intake was performed by examining sex, age, body mass index (BMI), salty eating habit and dietary behaviors. Results: The degree of sodium reduction practice was significantly higher in salinity meter use (P < 0.001), low salt seasonings (P < 0.001) and efforts to make the foods as bland as possible overall (P < 0.001) in the restaurants participating in sodium reduction project than in homes (P < 0.001). The degree of sodium reduction practice appeared lower in the high salty food preference group than in the low-preference group in such items as efforts to make the foods as bland as possible overall (P < 0.05) and washing the salty taste and then cooking (P < 0.05). The high-preference group showed high-salt dietary behavior, including eating all the soup until nothing was left (P < 0.05) more than the low-preference group, but low-salt dietary behavior included checking the sodium content in processed foods (P < 0 .0 5) less than the low-preference group. The high-preference group was higher in the soup and stew intake frequency than the low-preference group (P < 0.05) and much lower in nuts (P < 0.05) and fruits (P < 0.05) intake frequency. The high-preference group had a higher salty eating habit (P < 0.05), salty taste assessment (P < 0.05) and estimated sodium intake (P < 0.05) than the low-preference group. Conclusions: The present study showed that the salty food preference was strongly associated with lower sodium reduction practice and higher estimated sodium intake.

• Journal of the Korean Society for information Management
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• v.38 no.4
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• pp.231-250
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• 2021

Despite the increasing number of international students in Korea, there is a lack of research on the health information-seeking behavior of international students. This study examined the health information search behavior of international students in Korea through a questionnaires and in-depth interviews adopting Critical Incident Technique. Most frequent health information needs that the participants experienced were related to Covid-19 and locating doctors/hospitals. The difficulties in seeking health information were language barriers, lack of knowledge of the Korean medical system, insufficient or overflowing information on the Internet. However, despite the language barrier, international students mainly used Korean sources (friends/family, websites, social media) for searching health information. In order to search health information on Korean websites, they used Google Translator or got help from bilingual friends/family members. The participants who have lived in Korea for a shorter period of time or who have lower Korean language proficiency tend to obtain health information through the community on social networks; whereas the longer the period of residence in Korea and the better the Korean language proficiency, the more likely to use websites. Only 28% of the participants gave positive answers to the question asking their confidence in finding the health information they needed. It is discussed how to help international students find accurate and credible health information.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.305-314
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• 2020

The purpose of this study was to provide basic information on regional senior welfare policy setting for the elderly in the metropolitan and nonmetropolitan areas and on the development of senior welfare programs on the basis of the data of the 2019 community health survey conducted by Korea Disease Control and Prevention Agency. The subjects in this study were 74,547 senior citizens who were at the ages of 65 and over as of 2019 and who were 17,423 from the metropolitan area and 57,124 from the nonmetropolitan areas. The collected data were analyzed by SPSS version 26.0. The findings of the study were as follows: As for the levels of happiness in the metropolitan area, happiness was better in the seniors who were aged 75 and up, who had spouses, whose income was larger and who engaged in economic activity. In the nonmetropolitan areas, happiness was better in the seniors who were aged 75 and up, who were better educated, who had spouses, whose income was larger and who engaged in economic activity. In terms of health behaviors and subjective health levels, more happiness was felt by the seniors who didn't smoke at present, who didn't suffer any subjective stress, who were at higher subjective health levels and higher subjective oral health levels and who had unmet health care needs, no matter whether they dwelled in the metropolitan or nonmetropolitan areas. In the nonmetropolitan areas, however, engaging in intensive physical activity and lower BMI were identified as the factors to affect happiness.

• Journal of Digital Convergence
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• v.19 no.5
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• pp.81-92
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• 2021

The purpose of this study is to present an approach to the "Digital Health Passport" (DHP), which will be the most important in the change of the travel industry among the sudden environmental changes brought about by COVID-19. To this end, this study reviewed a variety of empirical literature on DHP, and proposed a framework for DHP based on literature review. The framework is composed of travel intention, health information provision intention, and new technology acceptance/adoption of tourists. First, in terms of travel intention, providing information to DHP should not undermine the travel intention of the travelers. It should be possible to facilitate the travelers' enjoyment by using the information provided by the traveler. In addition, there is a need to assure that the data provided by travelers is managed in a reliable way. Second, it is necessary to understand why the travelers want to provide additional personal information (information disclosure), rather than seeing healthcare information only in terms of mandatory information provision. Finally, from the perspective of new technology, it is necessary to understand the intention of travelers to use/adopt DHP. The key implication of this work is that it proposed a DHP framework for realizing the travel bubble to predict and respond to foreign travelers' behaviors.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.597-610
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• 2022

Knowledge of the failure behavior of friction materials considering their intermediate principal stress is related to an understanding of situations where these materials might be used: for example, the stability of deep-seated boreholes and fault slip analysis. This study designed equipment for physically implementing true triaxial compression and used it to assess specimens of plaster, a friction material. The material's mechanical behaviors are discussed based on the results. The applicability of the 3D failure criteria are also reviewed. The tested specimens were molded cuboids of width, length, and height 52, 52, and 104 mm, respectively. A total of 24 true triaxial compression tests were performed under various combinations of 𝜎₃ and 𝜎₂ conditions. Conventional uniaxial and triaxial compression tests were employed to estimate the mechanical properties of the plaster for use as parameters for 3D failure criteria. Examining the stress-strain relations of the plaster materials showed that a large difference between the intermediate principal stress and the minimum principal stress indicated strong brittle behavior. The mechanical behavior of the plaster used here reflects the change of intermediate principal stress. Nonlinear multiple regression analysis on the test data in the principal space showed that the modified Wiebols-Cook failure criterion and the modified Lade failure criterion were the most suitable 3D failure criteria for the tested plaster.