• ETRI Journal
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• v.42 no.5
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• pp.748-760
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• 2020

MapReduce is a framework that can process huge datasets in parallel and distributed computing environments. However, a single machine failure during the runtime of MapReduce tasks can increase completion time by 50%. MapReduce handles task failures by restarting the failed task and re-computing all input data from scratch, regardless of how much data had already been processed. To solve this issue, we need the computed key-value pairs to persist in a storage system to avoid re-computing them during the restarting process. In this paper, the task failure resilience (TFR) technique is proposed, which allows the execution of a failed task to continue from the point it was interrupted without having to redo all the work. Amazon ElastiCache for Redis is used as a non-volatile cache for the key-value pairs. We measured the performance of TFR by running different Hadoop benchmarking suites. TFR was implemented using the Hadoop software framework, and the experimental results showed significant performance improvements when compared with the performance of the default Hadoop implementation.

• International Journal of Highway Engineering
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• v.20 no.1
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• pp.35-45
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• 2018

PURPOSES : This study examines the performance changes of road networks according to the strength of a disaster, and proposes a method for estimating the quantitative resilience according to the road-network performance changes and damage scale. This study also selected high-influence road sections, according to disasters targeting the road network, and aimed to analyze their hazard resilience from the network aspect through a scenario analysis of the damage recovery after a disaster occurred. METHODS : The analysis was conducted targeting Sejong City in South Korea. The disaster situation was set up using the TransCAD and VISSIM traffic-simulation software. First, the study analyzed how road-network damage changed the user's travel pattern and travel time, and how it affected the complete network. Secondly, the functional aspects of the road networks were analyzed using quantitative resilience. Finally, based on the road-network performance change and resilience, priority-management road sections were selected. RESULTS : According to the analysis results, when a road section has relatively low connectivity and low traffic, its effect on the complete network is insignificant. Moreover, certain road sections with relatively high importance can suffer a performance loss from major damage, for e.g., sections where bridges, tunnels, or underground roads are located, roads where no bypasses exist or they exist far from the concerned road, including entrances and exits to suburban areas. Relatively important roads have the potential to significantly degrade the network performance when a disaster occurs. Because of the high risk of delays or isolation, they may lead to secondary damage. Thus, it is necessary to manage the roads to maintain their performance. CONCLUSIONS : As a baseline study to establish measures for traffic prevention, this study considered the performance of a road network, selected high-influence road sections within the road network, and analyzed the quantitative resilience of the road network according to scenarios. The road users' passage-pattern changes were analyzed through simulation analysis using the User Equilibrium model. Based on the analysis results, the resilience in each scenario was examined and compared. Sections where a road's performance loss had a significant influence on the network were targeted. The study results were judged to become basic research data for establishing response plans to restore the original functions and performance of the destroyed and damage road networks, and for selecting maintenance priorities.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.137-144
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• 2023

Cyberattack technology is evolving to an unpredictable degree, and it is a situation that can happen 'at any time' rather than 'someday'. Infrastructure that is becoming hyper-connected and global due to cloud computing and the Internet of Things is an environment where cyberattacks can be more damaging than ever, and cyberattacks are still ongoing. Even if damage occurs due to external influences such as cyberattacks or natural disasters, intelligent self-recovery must evolve from a cyber resilience perspective to minimize downtime of cyber assets (OS, WEB, WAS, DB). In this paper, we propose an intelligent self-recovery technology to ensure sustainable cyber resilience when cyber assets fail to function properly due to a cyberattack. The original and updated history of cyber assets is managed in real-time using timeslot design and snapshot backup technology. It is necessary to secure technology that can automatically detect damage situations in conjunction with a commercialized file integrity monitoring program and minimize downtime of cyber assets by analyzing the correlation of backup data to damaged files on an intelligent basis to self-recover to an optimal state. In the future, we plan to research a pilot system that applies the unique functions of self-recovery technology and an operating model that can learn and analyze self-recovery strategies appropriate for cyber assets in damaged states.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.339-346
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• 2018

The purpose of this study is to investigate the relationship between emotional labor, resilience, and psychological well-being in clinical nurses, and to investigate ways to improve their psychological well-being. Data collection was conducted for nurses working in two general hospitals housing 300 beds in Incheon and Chungcheongnam-do. A total of 187 nurses were interviewed from June 10 to August 20, 2016. Data were analyzed using frequency and percentage, mean, standard deviation, t-test, analysis of variance (ANOVA), Pearson's correlation, and multiple regression analysis. In this research, 94.7% of the subjects were female, their mean age was 29.80, 61.5% of them had received associate of nursing degrees, and 70.6% were single. Results of the research showed that emotional labor averaged $3.37{\pm}.50hours$, resilience was $3.29{\pm}.45hours$, and psychological well-being was $3.25{\pm}.47hours$. There was a negative correlation (r=-.165, p<.05) between time spent on emotional labor and psychological well-being, and a positive correlation between time spent on recovery resilience and psychological well-being (r=.686, p<.01). Resilience was a predictor of psychological well-being, explained by a rating of 46.8% (F=164.43, p<.001). Based on the results of this study, developing a program that can improve resilience to improve the psychological well-being of clinical nurses involved in high emotional labor is suggested.

• Elastomers and Composites
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• v.44 no.4
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• pp.442-446
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• 2009

Recovery behaviors of unfilled NR, BR, and SBR vulcanizates after aging with a circular deformation were compared to prevent the influence of reinforcing agent. Samples were aged at room temperature, 50, 70, and $90^{\circ}C$ for 10 days. Recovery increased by increasing the measurement time. Instantaneous recoveries less than 1.0 sec were obtained using the recovery variations with the measurement time. For aging at room temperature, difference in the recoveries of the rubber samples was not significant because the aging time was too short. However, for accelerated thermal aging at 50, 70, and $90^{\circ}C$, difference in the recoveries of the rubber samples was significant. Degree of recovery of BR specimen was higher than those of the others, while that of SBR was lowest. However, for accelerated thermal aging at $90^{\circ}C$, recovery of the NR sample was higher than that of the BR one. The initial recovery decreased by increasing the aging temperature and the decrement of SBR was larger than the others. The experimental results were explained with the resilience properties of rubbers and the crosslink density changes by thermal aging.

• Elastomers and Composites
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• v.52 no.4
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• pp.280-286
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• 2017

The mechanical and dynamic properties according to the content of filler, plasticizer, and crosslinking agent of rubber composites for Lipseal were measured in this study. The mechanical properties of the composite including the silane coupling agent and silica were found to be superior to those of the composite containing carbon black. It was found that the rebound resilience characteristics were influenced by the crosslink density of sulfur rather than the filler or plasticizer. In the case of recovery, it was confirmed that the elastic restoring force improved in the compression deformation condition and recovery increased as the crosslinking density increased. The rubber composite for Lipseal of this study is expected to improve the manufacturing technology of the rubber composite which can implement the optimum function for recognizing the performance such as oil resistance, durability and compression set.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.456-463
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• 2018

Increases in disasters and damage caused by the disasters in modern society, have a negative impact on local economy. In particular, a local economic downturn leads to a deterioration in quality of life of local residents and causes mental and material damage. Therefore, in order to achieve stable and sustainable local economic development, it is necessary to strengthen the resilience of the local economy. This study aims to estimate indicators of local economic resilience of Jindo County after the Sewol Ferry disaster, analyze a trend of the economic level after the disaster through time series data and suggest improvement plans of the local crisis management and restoration policy that considers future economic resilience. Results of this study showed that a decrease in the number of tourists and of workers in related industries hit tourism industry, causing a loss to the local economy and that an increase in a drinking rate of and stress awareness rate of local residents was a stress factor due to disaster impacts. These findings provides policy implications that it is necessary to make efforts for improving the depressed local image by utilizing local resources in the area, to build a sustainable long-term economic recovery policy and to provide psychological treatment and the relevant government and local government's support for relieving the stress of local residents due to the disaster impacts.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.100-107
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• 2021

This study was a descriptive research to investigate the effects of resilience and personality types on the major satisfaction of nursing students. The participants of this study were nursing students who were attending two universities in D city. Data collection was conducted from September 8 to October 6, 2020. The SPSS/WIN 26.0 program was used for data analysis. Frequency and percentage, mean and standard deviation, Pearson's correlation, independent sample t-test, one-way ANOVA, and multiple regression were used for analysis. The results of this study showed that the average recovery elasticity of nursing students was 3.50 points (5 points), personality type was 2.28 points (4 points), and major satisfaction was 3.12 points (5 points). Personality type A was found in 122 people and personality type B in 136 people. It was found that there was a positive correlation between resilience and major satisfaction, which indicates that the higher the resilience, the higher the major satisfaction. The major satisfaction of nursing students was found to be a significant factor influencing college life satisfaction and human relationships in personality type A, showing 46.2% explanatory power. In personality type B, it was found to be a significant influencing factor in grade and human relationships, showing 42.5% explanatory power. From the above study results, it can be inferred that the development of a college application program that can improve human relationships and increase resilience in college life is required to inspire major satisfaction.

• Journal of Naturopathy
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• v.11 no.2
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• pp.85-92
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• 2022

Background: Research is necessary to enhance the mental health of psychiatric unit nurses and the quality of nurse services. Purpose: This study was to obtain primary data for enhancing the psychological well-being of psychiatric nurses by investigating the factors that affect them. Methods: This study was conducted as a descriptive research study. The study period was from February 18 to March 31, 2019, with the subjects being 150 psychiatric nurses working in the ward of a psychiatric hospital in Gyeongnam. We used questionnaires on job stress measurement, the Korean version of the interpersonal response index, resilience scale, and psychological well-being. The collected data were analyzed using the SPSS program. Results: The subjects' levels of the job stress, empathy, resilience, and psychological well-being ranged from 2.34 to 3.33 points. The level of recovery resilience and well-being according to the subject's characteristics is 40 years or older, married, religious, ten years of nurse experience, above average economic level, psychiatric qualifications, senior nurse or higher, resilience education. All participants were significantly (p < .001). Conclusions: In this study, psychological well-being increased as the job stress was low and empathy and resilience were high. Therefore, it should make a proper education program to improve the strength and well-being of psychiatric nurses.

• Fire Science and Engineering
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• v.15 no.2
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• pp.20-30
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• 2001

The science and technology of seismic hazard mitigation are increasingly being shared among scientists and policy makers around the world. Administrative expertise is also being shared. While there is still tremendous unevenness in technical and administrative capacities and resources, a global community of emergency managers is developing and there is a globalization of expertise. Hazards are better understood, tools for risk assessment are improving, techniques for hazard mitigation are being perfected, and communities and states are implementing more comprehensive disaster preparedness, response, and recovery programs. Priorities are also emerging and hazard mitigation has emerged as the priority of choice in North America and Europe. An increasingly important component of hazard mitigation is resilience, in terms of increased capacities for disaster mitigation and recovery at the community and even individual levels. Each year, more is known about the locations and natures of seismic hazards, although there are still unknown and poorly understood fault lines and limited understanding of related disasters such as tsunamis and landslides. More is known about the impact of earthquakes on the built environment, although nature still provides surprises to confound man's best extorts to reduce risk. More is known about human nature and how people respond to uncertain risk and when confronted by certain catastrophe. However, despite the increased understanding of seismic phenomena and how to protect people and property, there is much that needs to be done to reduce the risk, particularly in major metropolitan areas.