• Anxiety and mood
• /
• v.15 no.2
• /
• pp.94-100
• /
• 2019

Objective : The purpose of this study was to investigate differences in anxiety and depression symptoms, comorbidity according to the patterns of temperament and character in patients with posttraumatic stress disorder (PTSD). Methods : The temperament and character inventory (TCI), beck depression inventory (BDI) and beck anxiety inventory (BAI) were administered to 151 PTSD patients classified into four groups of adaptation, vulnerable temperament, immature personality and composite vulnerability according to the results of the Temperament and Character Inventory (TCI). MANOVA and Chi-square tests were conducted to analyze differences in BDI, BAI, temperament and character scores and rate of comorbid disorders between the four groups. Results : The immature character and complex vulnerability group showed the higher rate of comorbid depression disorder. Anxiety and depression severity were significantly different among groups, especially depression severity had higher scores in the immature character and complex vulnerability groups and anxiety severity had higher scores in the complex vulnerability group than adaptive group. The immature character and complex vulnerability groups showed significantly lower score on the temperament scale of reward dependence and persistent. Conclusion : The results demonstrate the significance of adaptive characteristics on anxiety and depression symptoms regardless of vulnerable temperaments, and its consequent role in the management of character factors relative to intervention regarding PTSD.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.29 no.1
• /
• pp.69-81
• /
• 2019

Objective: The purpose of this study was to find out what kind of change in death rate when job stress is solved by calculating job stress relieve coefficient. Methods: This study used the data of the fourth working condition survey. Regression analysis was used to determine the relationship between health effects recognition and Death rate per 10,000 workers. After that the recognizing and non - recognizing groups were categorized by health effects recognition, and the differences between the two groups were confirmed by cross tabulation analysis. Results: Regress analysis P-value is 0.011 and $R^2$ is 0.979. Death rate per 10,000 worker increased with the increase in the number of non - health impact recognizing group. The relieve factors were (1) work culture(2.859) (2) physical environment(2.184), (3) improper reward (1,839), (4) relationship conflict(1.646), (5) job requirement(1.613), (6) job autonomy(1.354), (7) job instability(1.334), And (8) organizational system(1.201). The higher the relieve coefficient is, the higher the probability of belonging to the non - health impact recognizing group when there is no job stress factor. Conclusions: When job stress is resolved, there is a high probability that the health impact recognition is reduced, which can lead to an increase in death rate. but according to previous studies, Job stress can cause accidents by reducing the safety behavior of accidents. The job stress management plan should simultaneously consider reducing job stress and increasing health impact recognition.

• Journal of Korean Society for Quality Management
• /
• v.46 no.4
• /
• pp.939-958
• /
• 2018

Purpose: The purpose of this study was to propose useful suggestions by analyzing causal effect relationship between quality of followership, perceived style of leadership, job satisfaction and team commitment in the aviation industry. Methods: For the analysis of this study, a survey was conducted on local flight attendant. A total of 364 surveys were collected and 336 effective samples were used for analysis. And the collected data were analyzed using Structural Equation Modeling. Results: The results of this study were as follows : First, In the relationship between quality of followership and perceived leadership styles, independent thinking has a positive effect on all six sub-factors of transformational and transactional leadership and active engagement has negative influence on all six sub-factors of transformational and transactional leadership. Inaddition As a result of total and direct and indirect effects, Idealized Influence of perceived leadership style indirectly influences between Quality of Followership and job satisfaction, Idealized Influence, Inspirational Motivation, Intellectual Stimulation, Individualized Consideration, Contingent Reward of perceived leadership style have been shown to have indirect effects on team Commitment Conclusion: Based on the characteristics of followers and the type of leadership, it is necessary to develop ways to develop job satisfaction and team commitment of airline crews. In addition, flight attendant act as leaders and followers of each other depending on their work characteristics. Therefore, it is necessary to understand the relationship between leadership and followership based on the results of this study.

• Korean Journal of Psychosomatic Medicine
• /
• v.28 no.2
• /
• pp.155-160
• /
• 2020

Objectives : This study investigate to identify the stability of temperament and personality characteristics of patients including Posttraumatic Stress Disorder (PTSD) patients. Methods : The number of subjects was 102, of which 33 were PTSD patients and 69 were non-PTSD patients. To demonstrate the change in individual temperament and personality characteristics, Temperament and Character Inventory (TCI) were administered repeatedly on the subjects. Repeated measures ANOVA and simple main effects analysis were conducted. Results : When analysed by dividing the subjects into PTSD groups and non-PTSD groups, the differences between the primary and secondary tests did not appear in the non-PTSD groups, but the differences between the primary and secondary tests were significant in Harm Avoidance (HA), Reward Dependence (RD), Self-Directedness (SD), Cooperativeness (C). In addition, it was noted that the time and group interaction effects of HA, RD, SD and C were significant, and that the main effects of time of HA, RD, SD and C were significant. Conclusions : This study is meaningful in that in the course of experience and recovery of traumatic events, we have clinically confirmed that changes in the temperament, known as stable variables, are possible.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.3
• /
• pp.9-17
• /
• 2021

In this paper, an autonomous multi-agent path planning using reinforcement learning for monitoring of infrastructures and resources in a computationally distributed system was proposed. Reinforcement-learning-based multi-agent exploratory system in a distributed node enable to evaluate a cumulative reward every action and to provide the optimized knowledge for next available action repeatedly by learning process according to a learning policy. Here, the proposed methods were presented by (a) approach of dynamics-based motion constraints multi-agent path-planning to reduce smaller agent steps toward the given destination(goal), where these agents are able to geographically explore on the environment with initial random-trials versus optimal-trials, (b) approach using agent sub-goal selection to provide more efficient agent exploration(path-planning) to reach the final destination(goal), and (c) approach of reinforcement learning schemes by using the proposed autonomous and asynchronous triggering of agent exploratory phases.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.11
• /
• pp.4268-4289
• /
• 2020

Advanced traffic signal timing method plays very important role in reducing road congestion and air pollution. Reinforcement learning is considered as superior approach to build traffic light timing scheme by many recent studies. It fulfills real adaptive control by the means of taking real-time traffic information as state, and adjusting traffic light scheme as action. However, existing works behave inefficient in complex intersections and they are lack of feasibility because most of them adopt traffic light scheme whose phase sequence is flexible. To address these issues, a novel adaptive traffic signal timing scheme is proposed. It's based on actor-critic reinforcement learning algorithm, and advanced techniques proximal policy optimization and generalized advantage estimation are integrated. In particular, a new kind of reward function and a simplified form of state representation are carefully defined, and they facilitate to improve the learning efficiency and reduce the computational complexity, respectively. Meanwhile, a fixed phase sequence signal scheme is derived, and constraint on the variations of successive phase durations is introduced, which enhances its feasibility and robustness in field applications. The proposed scheme is verified through field-data-based experiments in both medium and high traffic density scenarios. Simulation results exhibit remarkable improvement in traffic performance as well as the learning efficiency comparing with the existing reinforcement learning-based methods such as 3DQN and DDQN.

• Journal of Korean Biological Nursing Science
• /
• v.23 no.2
• /
• pp.91-99
• /
• 2021

Purpose: This study aimed to identify occupational stress and health problems as well as turnover reasons among leavers in novice nurses and to estimate factors which might affect turnover by comparing them to stayers. Methods: In this study, secondary analysis of data gathered from the Shift Work Nurse's Health and Turnover studies, was carried out. The data were collected from 204 stayers who have been working for 18 months since 2018 and 48 leavers who left within the same period at two tertiary hospitals in Seoul. The reasons for turnover, occupational stress, and 8 types of health problems were recorded. The data were analyzed using SAS 9.4 to obtain descriptive statistics. In parallel, Pearson's chi-squared test, Fisher's exact test, and independent t-test were also conducted. Results: The main reasons for turnover were job stress and difficult interpersonal relationships in the workplace. Occupational stress of leavers was higher than stayers, especially in the subscales of interpersonal conflict, organizational system, lack of reward, and occupational climate. Among the 8 types of health problems, the depression prevalence of leavers was higher compared to stayers and showed marginal significance. Unexpectedly, the sleep disturbance prevalence of stayers was significantly higher compared to leavers. Conclusion: To reduce the turnover rate of novice nurses, education on how to cope with occupational stress is needed. A customized program for novice nurses to overcome the difficulties of interpersonal relations would be helpful.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.8
• /
• pp.1148-1157
• /
• 2022

In 2019, COVID-19 changed many people's lives. Among them, metaverse supports non-face-to-face services through various methods, replacing daily tasks. This phenomenon was created and formed like a culture due to the prolonged COVID-19. In this paper, the fun elements used in the existing game were organized to find out the fun factors of the metaverse, and the items and contents were reclassified according to the metaverse with five experts. Classification was classified using reproducibility, sensory fun [graphic, auditory, text, manipulation, empathy, play, perspective], challenging fun [absorbedness, challenging, discovery, thrill, reward, problem-solving], imaginative fun [new story, love, freedom, agency, expectation, change], social fun[rules, competition, social behavior, status, cooperation, participation, exchange, belonging, currency transaction], interactive fun[decision making, communication sharing, hardware, empathy, nurturing, autonomy], realistic fun[sense of unity in reality, easy of learning, adaptation, intellectual problems solving, pattern recognition, sense of reality, community], and creative fun[application, creation, customizing, virtual world].

• KNOM Review
• /
• v.23 no.1
• /
• pp.26-33
• /
• 2020

Bitcoin is an electronic money that does not rely on centralized institutions such as banks and financial institutions, unlike the world's paper currencies such as dollar, won, euro and yen. In Bitcoin network, a block with transaction details is generated by mining, and the message that the block has been created is broadcast to all participating nodes in a broadcasting method to secure reliability through verification. Likewise, the mining and block propagation methods in the Bitcoin network are greatly affected by the performance of the P2P network. For example, in the case of mining, the node receiving the reward for mining varies depending on whether the block is first mined in the network and the proof of mining is propagated faster. In this paper, we applied local characteristics and Round-to-Trip(RTT) measurement to solve the problems of the existing neighbor connection method and block propagation method performed in Bitcoin network. An algorithm to improve block propagation speed is presented. Through experiments, we compare the performance of the improved algorithm with the existing algorithm to verify that the overall block propagation time is reduced.

• Journal of The Korean Society of Integrative Medicine
• /
• v.10 no.4
• /
• pp.209-218
• /
• 2022

Purpose : This study examined how of nursing students affects their academic self-efficacy and communication ability on self-leadership. Methods : The subjects of this study included 269 nursing students enrolled in a college located in City B, South Korea during a period between June and July 2021. The collected data were analyzed using SPSS/WIN 22.0 program to compute frequency, percentage, mean and standard deviation and conduct t-test, ANOVA, Scheffe's test, Pearson Correlation Coefficient, and multiple regression analysis. Results : The nursing students had average academic self-efficacy of 3.10±.42, communication ability of 3.78±.53, and self-leadership of 3.16±.44. Among the self-leadership sub-factors, self-reward was the highest with 3.94±.74 points. The academic self-efficacy of the subjects demonstrated a significant difference according to happiness index (F=8.83, p<.001) and health (F=3.38, p=.035). The communication ability showed a significant difference depending on year of study (F=5.62, p<.001), happiness index (F=5.95, p<.001), and experience of clinical training (t=-3.57, p<.001). The self-leadership demonstrated a significant difference according to year of study (F=4.28, p=.006), satisfaction with major (F=7.37, p<.001), happiness index (F=3.68, p=.013), and experience of clinical training (t=-3.41, p<.001). A positive correlation was observed between the subject's academic self-efficacy and communication ability (r=.40, p<.001), as well as the academic self-efficacy and self-leadership (r=.45, p<.001). The communication ability (𝛽=.36, p<.001) was proven to be the strongest influential factor on the self-leadership, followed by academic self-efficacy (𝛽=.28, p<.001), satisfaction with major (𝛽=.13, p=.011), and experience of clinical training (𝛽=.13, p=.013). Conclusion : This study results imply that repeated studies that investigate the nursing students' academic self-efficacy, communication ability, and self-leadership are required. Furthermore, efforts should be made to develop programs aimed at enhancing nursing students' academic self-efficacy, communication ability, and self-leadership.