• Korean Journal of Applied Biomechanics
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• v.31 no.1
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• pp.72-78
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• 2021

Objective: The purpose of this study was to investigate relations and effectiveness about mountain climbling exercise with different level of support surfaces by analyzing heart rate and EMG data. A total of 10 male college students with no musculoskeltal disorder were recruited for this study. Method: The biomechanical analysis was performed using heart rate monitor (Polar V800, Polar Electro Oy, Finland), step-box, exercise mat, and EMG device (QEMG8, Laxtha Inc. Korea, sampling frequency = 1,024 Hz, gain = 1,000, input impedance > 1012 Ω, CMRR > 100 dB). In this research, step-box were used to create different surface levels on the upper body (flat surface, 10% of subject's height, 20% of subject's height, and 30% of subject's hight). Based on these different conditions, data was collected by performing mountain climbing exercise during 30 seconds. Subjects were given 5 minutes of break to prevent muscular fatigue after each exercise. For each dependent variable, a one-way analysis of variance with repeated measures was conducted to find significant differences and Bonferroni post-hoc test was performed. Results: The results of this study showed that exercise intensity was reduced statistically as increased surface level on the upper body. Muscle activity of the upper rectus abdominis and biceps femoris for 30% of surface level was significantly higher than the corresponding values for flat surface. However, the opposite was found in the rectus femoris. In general, muscle activity of the lower rectus abdominis, erector spinae, external oblique abdominis, and gluteus maximus increased when surface level increased, but the differences were not significant. Conclusion: As a result, the increase in surface level of the body would change muscle activity of the upper body, indicating that different surface level of the upper body may cause significant effect on particular muscles to be more active during mountain climbing exercise. Based on results of this study, it is suggested to set up an appropriate surface level to target particular muscle to expect an effective training. It is also important to set adequate surface levels to create an effective training condition for preventing exercise injuries.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.44-50
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• 2021

This study is a descriptive research study to determine the effect of job stress and job satisfaction of 119 paramedics on their job performance ability. The subjects were 119 paramedics working at the fire department who agreed to participate in the study, and data collection was conducted from July 1st to September 10th, 2020. Data analysis was performed using the SPSS 23.0 program, with frequency and percentage, mean and standard deviation, correlation analysis, t-test, and ANOVA. As a result, the average job stress, job satisfaction, and job performance ability of 119 paramedics were 2.85±0.29 points, 3.35±0.30 points, and 3.53±0.89, respectively. A higher job satisfaction indicated higher job performance ability. An examination of the characteristics of the variables according to the general characteristics showed that the job performance ability was related significantly to the marital status, age, and first aid experience. Based on this, to establish a positive professional intuition to increase the job performance ability of 119 paramedics, lower job stress, and increases job satisfaction, it is important to raise awareness of job satisfaction, establish a job view, and promote job satisfaction through performance improvement. Program development and education programs for children should be actively carried out.rough performance improvement. Program development and education programs for children should be actively carried out.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.531-552
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• 2020

In the previous study, both the wave characteristics at the tip of composite breakwater and on caisson were investigated by applying olaFlow numerical model of three-dimensional regular waves. In this paper, the same numerical model and layout/shape of composite breakwater as applied the previous study under the action of one directional irregular waves were used to analyze two and three-dimensional spatial change of wave force including the impulsive breaking wave pressure applied to trunk of breakwater, the effect of rear region, and the occurrence of diffracted waves at the tip of caisson located on the high crested rubble mound. In addition, the frequency spectrum, mean significant wave height, mean horizontal velocity, and mean turbulent kinetic energy through the numerical analysis were studied. In conclusion, the larger wave pressure occurs at the front wall of caisson around the still water level than the original design conditions when it generates the shock-crushing wave pressure in three-dimensional analysis condition. Which was not occurred by two-dimensional analysis. Furthermore, it was confirmed that the wave pressure distribution at the caisson changes along the length of breakwater when the same significant incident wave was applied to the caisson. Although there is difference in magnitude, but its variation shows the similar tendency with the case of previous study.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.34-41
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• 2020

In recent years, magnitude and frequency of earthquakes have increased in Korea. Damage to a bridge, which is one of the main infrastructures, can directly lead to considerable loss of human lives. Therefore, engineers need to evaluate the seismic fragility of the structure and prepare for the possible seismic damage. In particular, the number of aging bridges over 30 years of service increases, and thus the seismic analysis and fragility requires accounting for the aging and retrofit effects on the bridge. In this study, the nonlinear static and dynamic analyses were performed to evaluate the effects of the aging and FRP retrofit on a PSC bridge. The aging and FRP retrofit were applied to piers that dominate the response of the bridge during earthquakes. The maximum displacement of the bridge increased due to the aging of the pier but decreased when FRP retrofit applied to the aged pier. In addition, seismic fragility analysis was performed to evaluate the seismic behavior of the bridge combined with the seismic performance of the pier. Compared with the aged bridge, the FRP retrofit bridge showed a decrease in the seismic fragility in all levels of damage. The reduction of the seismic fragility in the FRP bridge was prominent as the value of PGA and level of damage increased.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.196-207
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• 2021

The purpose of this study is to investigate the relationship between trust, satisfaction and cognitive performance of golf participants in golf device, focusing on the swing analyzer. A total of 328 questionnaires were collected. Collected data were analyzed by SPSSWIN and AMOS program and frequency analysis, confirmatory factor analysis, validity test, correlation analysis and structural equation model analysis were performed. The result of the study were as follows. First, the trust of golf participants in golf device data has a positive effect on satisfaction. Second, the trust of golf participants in golf device data does not affect Perceived performance. Third, the satisfaction of golf participants in golf device data does not affect Perceived performance. In conclusion, golf participants' trust and satisfaction of the golf swing analyzer are irrelevant to the perceived performance. In conclusion, it was found that golf participants trusted the data presented through the golf device and obtained satisfactory results. However, in that it did not affect the perceived performance, golf participants can think that golf devices should be used to play golf rather than thinking that golf devices enhance their performance.

• Journal of Korean Library and Information Science Society
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• v.52 no.2
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• pp.253-274
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• 2021

With the introduction of 'Reading One Book a Semester' in the 2015 curriculum, more and more activities are being done to read the same books on a classroom basis. Accordingly, librarians need to properly support the teacher's book recommendation and book selection process, which consists of classes. This study aims to establish effective school library services based on this by identifying differences in elementary school students' reading interests when reading a book recommended by a teacher in the class. To this end, all students of A Elementary School were given a book selection class by class to select one of the teacher's recommended books, and students were interested in reading before and after reading. As a result, students who read the books they chose showed higher 'interest after reading' than those who read the books they did not choose. However, students who had high 'interest before reading' even though they read books they did not choose showed high 'interest after reading'. 'Interest before reading' were higher for students who were provided with book information evenly and used the school library more frequently. Therefore, librarians need to provide a variety of book information and services to increase the frequency of school library use to increase 'interest before reading', which positively affects self-selective reading.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.699-706
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• 2021

This study aims to identify the effects of factors on aggression in adolescents, focusing on the individual, parent, friend factors and SNS usage. In particular, this study is to provide a basis for easing aggression in adolescence by considering the emotional relationship of parents and friends. This study analyzed frequency, t-test, one-way batch distribution analysis(ANOVA), and multi-linear regression, using the data from the 7th year of the Korean Children and Youth Panel Survey. As a result, adolescents who frequently use SNS are more aggressive than adolescents who use less. Among the parental factors, the more abuse and excessive interference were found to be more aggressive, and the higher the coach, the lower the aggressiveness. Furthermore, among the friend factors, it has been shown that the higher the alienation, the more aggressive adolescents are. In order to reduce aggression among adolescents, it is necessary to prepare an integrated program considering the emotional relationship of parents and friends, who are the most influential neighbors, rather than simply restricting the use of SNS.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.627-637
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• 2021

Many efforts have been made to prevent alcohol related harms such as health problems and socio-economic problems. Among them, the method of improving drinking behavior at the individual level is the most direct intervention. The effectiveness of the use of protective behavior strategies(PBS) has been widely known in Western countries. The purpose of this study is to empirically verify whether the use of PBS affects alcohol related harms in Korean adults. The survey has been conducted on 2,000 adult men and women. As a result, it is found that the use of PBS reduced alcohol related harms in adults. Among the PBS, the biggest impact on alcohol related harms is the area related serious harm reduction strategy, followed by restrictions on 'manner of drinking'. The effects of 'limiting/ stopping of drinking' is not significant. In addition, drinking frequency, binge drinking, and drinking motivations have significant positive effects on alcohol-related harms, and only social motivation has a negative effect. In this work, we propose follow-up studies on identifying relationships between protective behaviors and alcohol related factors through longitudinal studies and strengthening the use of protective behavior strategies that applied to the refined target populations.

• Journal of Korean society of Dental Hygiene
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• v.22 no.1
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• pp.11-19
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• 2022

Objectives: The purpose of this study was to identify new variables that can enhance adult oral health behaviors by confirming the degree of adult e-health literacy, oral health knowledge, and oral health behaviors and examining their relevance. Methods: A self-reported questionnaire was filled out by 350 adults from June 22 to August 1, 2021. Data were analyzed using SPSS 23.0. independent t-test, one way ANOVA, the scheffé post-hoc test and the pearson correlation coefficients were reviewed, A hierarchical regression analysis was conducted. Results: Oral health behaviors according to general characteristics showed significant differences in gender, educational background, dental visit within 1 year, subjective oral health status, oral health interest, frequency of oral internet use, and reliability of internet oral health information. Also it was found that e-health literacy affects oral health behavior. Conclusions: In this study, e-health literacy, oral health knowledge, and oral health behavior were correlated and it was confirmed that e-health literacy had an effect on oral health behavior. In the future, it is necessary to develop a tool that can measure e-oral health literacy and to find a way to improve the oral health behavior of adults by using e-oral health literacy.

• Knowledge Management Research
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• v.23 no.1
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• pp.47-67
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• 2022

Computer and Internet information technologies(ICTs) have changed the modern service industry and people's life style. In particular, the global spread of COVID-19 has attracted more attention to contact service types such as self-service technology. With the increase in labor costs and the enhancement of consumer self-awareness, more and more companies transfer part of their work to customers through their own service technology. This study seeks to answer the following questions. (1) Do technology difficulty and safety perception affect customer value recognition in the self-service technologies? (2) Does customer value recognition influence the intention to use such technologies continuously? This study conducted an empirical analysis with 327 samples to validate the influence of self-service characteristics(technology difficulty and safety perception) on customer value recognition and continuous utilization intentions. Also, it analyzes the moderating effects of age and frequency of use on the relationship between self-service characteristics and customer value recognition. The study results show that the technology difficulty does not affect the customer's perceived value recognition; and the higher the customer's value recognition, the higher the intention of continuous use.