• Convergence Security Journal
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• v.22 no.1
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• pp.29-38
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• 2022

The importance of prevention of epidemics is increasing due to the serious spread of infectious diseases. For prevention of epidemics, we need to focus on the non-contact industry. Therefore, in this paper, a face recognition door lock that controls access through non-contact is designed and developed. First very simple features are combined to find objects and face recognition is performed using Haar-based cascade algorithm. Then the texture of the image is binarized to find features using LBPH. An non-contact door lock system which composed of Raspberry PI 3B+ board, an ultrasonic sensor, a camera module, a motor, etc. are suggested. To verify actual performance and ascertain the impact of light sources, various experiment were conducted. As experimental results, the maximum value of the recognition rate was about 85.7%.

• Composites Research
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• v.36 no.6
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• pp.422-428
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• 2023

The electrical contact resistance between the bipolar plate (BP) and the carbon felt electrode (CFE), which are in contact by the stack clamping pressure, has a great impact on the stack efficiency because of the relatively low clamping pressure of the vanadium redox flow battery (VRFB) stack. In this study, a polyethylene (PE) composite-CFE hybrid bipolar plate structure is developed through a local heat welding process to reduce such contact resistance and improve cell performance. The PE matrix of the carbon fiber composite BP is locally melted to create a direct contact structure between the carbon fibers of CFE and the carbon fibers of BP, thereby reducing the electrical contact resistance. Area specific resistance (ASR) and gas permeability are measured to evaluate the performance of the PE composite-CFE hybrid bipolar plate. In addition, an acid aging test is performed to measure stack reliability. Finally, a VFRB unit cell charge/discharge test is performed to compare and analyze the performance of the developed PE composite-CFE hybrid BP and the conventional BP.

• The Korean Journal of Coaching Psychology
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• v.7 no.3
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• pp.57-80
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• 2023

This study aimed to examine the influence of intergenerational contact on work meaning through knowledge sharing. Additionally, based on the socioemotional selectivity theory, this study investigated whether age moderates the mediating path. We collected data from 588 full-time employees in South Korea, and analyzed the data using the latent moderated structural equation method. The results showed that knowledge sharing fully mediated the relationship between intergenerational contact and work meaning. Furthermore, age was found to moderate the relationship between intergenerational contact and work meaning via knowledge sharing. Particularly, the mediation effect was strengthened as age increased. This study holds a significant theoretical value by shedding light on the specific mechanisms underlying knowledge sharing. Moreover, the results suggest the potential for enhancing the impact of coaching programs by tailoring them to individual characteristics.

• Tunnel and Underground Space
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• v.19 no.6
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• pp.545-557
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• 2009

In order to investigate dynamic damage mechanism of brittle materials, Split Hopkinson Pressure Bar (SHPB) have been adapted to apply different impact levels to rocks in South Korea. High resolution X-ray Computed Tomography (CT) was used to estimate the damage in tested rock samples nondestructively. The cracks which are parallel to the loading axis are visible on the contact surface with the incident bar under lower level of impact. The surface cracks disappeared with increment of impact level due to confined effect between the incident bar and sample, while axial splitting are happened near the outer surface.

• Korean Journal of Child Studies
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• v.36 no.3
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• pp.93-113
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• 2015

The purpose of this study was to explore the currents status of exposure to internet pornography on the part of elementary students and to analyze the impact upon levels of sexual knowledge or sexual attitudes in such children. The participants in this study comprised 536 6th grade elementary school students. The data was analyzed by means of T-tests, F-tests, Pearson's correlation and regression analysis. The results were as follows. First, 32.5% of the subjects had experienced some degree of exposure to internet pornography. Second, sexual attitudes and sexual knowledge were found to be higher in accordance with the general characteristics exhibited by the girls, these same sexual attitudes and sexual knowledge amongst girls were observed to be even higher when they were exposed to internet pornography. Third, the characteristics of this exposure to internet pornography did not significantly impact on levels of sex knowledge. However, the characteristics of exposure to internet pornography did significantly impact upon sexual attitudes. In particular, gender permissiveness, attitudes regarding pornography, and attitudes towards physical contact did have a significant impact.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.8
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• pp.723-728
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• 2015

In the conventional hot rolling process, the defects of products such as scratches occur due to impact and friction. Impact occurs as a result of the contact of between rollers and the slab. Also, friction occurs in the rolling process. To improve these defects, a variety of processes were developed. The flying touch method is also one of the processes to reduce defects and uses a movable upper roller. To use this unfixed roller, the impact and frictions between rollers and the slab should be minimized. This paper proposes a hot rolling process simulator to verify and test the efficiency of the flying touch method. The simulator was designed to verify the method. This paper also proposes a new impact reducing method and velocity synchronization method which are simulated to realize the method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.12
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• pp.3847-3855
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• 1996

In order to study the relationship between static and cynamic behaviors of silion caride, both quasi-static indentaiton and impact experiments of spherical particle have been conducted. The difference inmaterial behavior when using the two mehtods suggests a loading rate difference in the damate pattrern and fracture strength of silicon carbide. This investigation showed some difference in damage pattern according to particla property, especially inthe case of particle impact. There was no differences in deformation behaviors according to the loading rate when the crater profiles were compared with each other at the same contact radius. From the result of residual strength evaluation, it was found that the strength degradation began at the initiation of ring crack and its behavior was colsely related to morphologies of the damage developed which was also dependent upon the extent of deformation atthe loaidng point. In the case of static indentation, there didnot exist the particle property effects onthe strength degradation behavior.

• The Journal of Industrial Distribution & Business
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• v.15 no.1
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• pp.1-8
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• 2024

Purpose: The purpose is to investigate the types of communication between aviation industry workers and passengers according to environmental changes following the COVID-19 pandemic. This study analyzes the impact of verbal and non-verbal communication styles of airport staff, especially those working at airline check-in counters, on passenger satisfaction. Research Design: The research design focuses on the impact of verbal communication styles and non-verbal communication factors of airline check-in counter staff, who represent the initial point of contact with passengers among airport staff, on passenger satisfaction. The survey period for sample collection was from July 1 to July 30, 2023, and the study was conducted targeting passengers boarding aircraft through Incheon Airport and Gimpo Airport. Result: First, it is important for airport staff to recognize all passengers, especially corporate customers, as corporate customers rather than simply as individuals boarding an airplane. Second, as the importance of non-verbal expressions increases due to the impact of COVID-19, physical and verbal responses are necessary. Third, it is important to check which language the passenger understands. Conclusions: Since communication through nonverbal expressions has become more important since COVID-19, airport employees need to recognize the importance of nonverbal communication. This awareness can serve as a foundation for building trust between airport staff and passengers.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.2
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• pp.154-159
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• 2013

In this paper, the effect of bolt clamping force and form accuray of contact surface between mirror and mount on mirror surface was studied. Normally, mirror used in reflecting optical system was assembled with mount by bolts or adhesive. In this case, the tension caused by bolt clamping force or adhesive force may distort the mirror surface. Also, form accuracy error of the contact surface have a negative impact on wrenched mirror surface which assembled by bolts or adhesive. In this study, stress and distorted displacements on mirror surface were analyzed according to the different contact surface form accuracies and bolt clamping forces by using the finite element analysis method.

• Korean Journal of Applied Biomechanics
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• v.30 no.3
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• pp.265-273
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• 2020

Objective: The aim of this study was to investigate the effect of participation in contact sports on neurocognitive scores, dual-task walking velocity, and cognitive costs in retired athletes. Method: Forty-four retired athletes (mean age = 26.4±5.5 yrs) and thirty-eight controls (mean age = 26.1±4.9 yrs) participated in this study. Neurocognitive score was collected using computerized neurocognitive testing using RehaCom. Gait velocity was collected one single task, four dual-tasks, and two multi-tasks using Optogait. Mann-Whitney U test was performed to compared differences in cognitive scores among groups. A mixed-design two-way ANOVA and Bonferroni posthoc test were used to assess the effect of group and walking tasks for each condition. Results: The auditory divided attention of neurocognitive score of retired athletes was higher than the control group (p < 0.05). No statistical differences were observed in the other neurocognitive scores between groups. The changes in walking velocity and cognitive costs according to the dual-task walking tests differed between the two groups (p < 0.05). Conclusion: Although participation in contact sports did not affect the neurocognitive results of retired athletes, it could be confirmed that the reduction in walking velocity and an increase in cognitive costs during dual-task walking. Rather than observing only neurocognitive scores as a single evaluation item for cognitive evaluation of retired athletes in relation to daily life, the application of the dual-task gait test may provide useful information.