• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.531-539
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• 2022

The government enforced policies such as social distancing and limiting business hours to prevent the spread of COVID-19. However, the impact of the long-term COVID-19 pandemic is causing more serious difficulties for small business owners. The government intended to relieve the business management pressure for small business owners by drawing up the COVID-19 emergency disaster relief funds. The funds provided temporary support for the small business owners, but the prolonged pandemic worsened the business management difficulties. Therefore, this study will apply fixes that fail and shifting the burden archetypes from the system archetype of system thinking for the exploratory deduction of policy measures as the policy leverage to effectively enhance the recovery of small business owners. In response to the situation, emergency financial aid for small business owners and support that can enhance the self-sustaining powers are required to heighten the recovery of small business owners.

• Earthquakes and Structures
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• v.22 no.5
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• pp.503-515
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• 2022

This paper presents the development of seismic fragility curves for a precast reinforced concrete bridge instrumented with a structural health monitoring (SHM) system. The bridge is located near an active seismic fault in the Dominican Republic (DR) and provides the only access to several local communities in the aftermath of a potential damaging earthquake; moreover, the sample bridge was designed with outdated building codes and uses structural detailing not adequate for structures in seismic regions. The bridge was instrumented with an SHM system to extract information about its state of structural integrity and estimate its seismic performance. The data obtained from the SHM system is integrated with structural models to develop a set of fragility curves to be used as a quantitative measure of the expected damage; the fragility curves provide an estimate of the probability that the structure will exceed different damage limit states as a function of an earthquake intensity measure. To obtain the fragility curves a digital twin of the bridge is developed combining a computational finite element model and the information extracted from the SHM system. The digital twin is used as a response prediction tool that minimizes modeling uncertainty, significantly improving the predicting capability of the model and the accuracy of the fragility curves. The digital twin was used to perform a nonlinear incremental dynamic analysis (IDA) with selected ground motions that are consistent with the seismic fault and site characteristics. The fragility curves show that for the maximum expected acceleration (with a 2% probability of exceedance in 50 years) the structure has a 62% probability of undergoing extensive damage. This is the first study presenting fragility curves for civil infrastructure in the DR and the proposed methodology can be extended to other structures to support disaster mitigation and post-disaster decision-making strategies.

• Journal of the Society of Disaster Information
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• v.14 no.1
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• pp.59-64
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• 2018

In the trend of increasing awareness of chemical accidents, hazardous chemical transport vehicle accidents are occurring every year. In this study, we analyzed improvement of accident prevention and countermeasures through statistical analysis of hazardous chemical transport vehicle accidents. A total of 383 chemical accidents between January 2014 and December 2017 were analyzed. During this period, number of transportation accidents was 83 cases, accounting for 21.67% of total chemical accidents. In the current system, despite the direct handling of hazardous chemical, it is out of regulation of damage prediction unlike the workplace. In order to effectively respond to actual accident, information on damage prediction is required and should be shared with related ministry. And it should be developed to real-time monitoring of hazardous chemical transport vehicle through integrated control tower.

• Structural Engineering and Mechanics
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• v.62 no.2
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• pp.197-208
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• 2017

Among various retrofitting strategies, use of semi-active control for retrofitting a building structure has gained momentum in recent years. One of the techniques for such retrofitting is to connect a weaker building to an adjacent stronger building by semi-active devices, so that performances of a weaker building are significantly improved for seismic forces. In this paper, a ten storey weaker building is connected to an adjacent stronger building using magneto-rheological (MR) dampers, for primarily improving the performance of the weaker building in terms of displacement, drift and base shear. For this, a fuzzy logic controller is specifically developed by fuzzyfying the responses of the coupled system. The performance of the control strategy is compared with the passive-on and passive-off controls. Pounding Mitigation between the two buildings is also investigated using all three control strategies. The results show that there exists a fundamental frequency ratio between the two buildings for which maximum control of the weaker building response takes place with no penalty on the stronger building. There exists also a fundamental frequency ratio where control of the weaker building response is achieved at the expense of the amplification of the stronger building. However, coupling strategy always improves the possibility of pounding mitigation.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.32-39
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• 2024

Purpose and Method: This study aims to suggest institutional improvements to enhance the response to electric vehicle fires. To this end, we examined the prevalence of electric vehicles, fires, and related legal systems in Seoul. Results: The top-level laws and ordinances related to electric vehicles are centered on distribution policies, so there is no practical fire response plan for electric vehicle fires. In order to apply the same regulations to each local government, it is necessary to set standards and establish a system for firefighting and safety facilities in higher laws. Conclusion: Establishing standards for the installation of fire and safety facilities that take into account the characteristics of electric vehicle fires and improving related systems will ultimately lead to an increase in the penetration rate of electric vehicles.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.232-243
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• 2024

Purpose: Recently, large-scale forest fires caused by climate change, natural disasters, and human factors have been increasing every year in the East Coast and Taebaek Mountains region. Although forest fire extinguishing using helicopters is currently increasing, the need to introduce air force transport aircraft has continued to be raised due to the importance of early fire extinguishment to respond to large forest fires and the difficulty of extinguishing forest fires between sheep. This study seeks to present a plan for developing a post-fire management system for several aspects - achieving operational objectives, overcoming the operating environment, selecting a staging area, and efficient operation measures - to efficiently perform forest fire extinguishing missions using Air Force transport aircraft. Method: Based on literature research on forest fire extinguishing, forest fire extinguishing experiments using fixed-wing aircraft, and the operation status and operation method of forest fire extinguishing helicopters, the pros and cons of helicopter operation and the effects of large forest fire extinguishing using a large transport aircraft (C-130) Analyze the effectiveness of operation through analysis. Results: When extinguishing a large forest fire, an effective CM (Consequence Management) application plan was derived, including effective operation, control, command system, dispatch request, and forest fire extinguishment when integrating helicopter and fixed-wing aircraft (C-130). Conclusion: The application of the concept of CM (Consequence Management) is partially applied to some areas of chemical, biological, and radiological (CBRNE) protection in Korea, but efficient operation, control, and command systems are established when integrated operation of helicopters and large aircraft (C-130) in forest fire extinguishment. the concept of CM (Consequence Management), which is operated in advanced countries, was applied for safety management, dispatch requests, and forest fire extinguishing, thereby contributing to the establishment of a more advanced disaster and post-disaster management system.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.3-16
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• 2003

After a not-widely-known fact is revealed that Japan is a leading country in production and use of industrial unmanned helicopters, a kind of UAV. The voice command system and the autonomous flight control system with a variety of control algorithms including neural network, robust and adaptive control that have been developed in collaboration between Kyoto University and Yamaha Motor Co., and funded by the Ministry of Education and Science of Japan are described in some detail. Both already-proven and promising future applications of the autonomous unmanned helicopters are given.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.59-65
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• 2008

This research attempts to consider disasters and calamities in the process of urban planning and road design. It presents a model that copes with disaster response. This model is an integrated system that performs the collective evaluation of roads, shelters, storage reservoirs and evacuation route systems. Consequently, this research attempts to discuss major issues to apply this system to cities.

• Journal of the Korean Geophysical Society
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• v.8 no.1
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• pp.7-14
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• 2005

Early detection in real-time response of slope movements ensures tremendous saving of lives and repair costs from catastrophic disaster. Therefore, it is essential to constantly monitor the performance and integrity of slope-stabilizing structures such as Rock bolt, Nail and Pile during or after installation. We developed a novel monitoring system using Fiber Bragg Grating (FBG) sensor. It's advantages are highly sensitivity, small dimension and electro-magnetic immunity. capability of multiplexing, system integrity, remote sensing - these serve real-time health monitoring of the structures. Real-time strain measurement by the signal processing program is shown graphically and it gives a warning sound when the monitored strain state exceeds a given threshold level so that any sign of abnormal disturbance on the spot can be easily perceived.

• Journal of the Korean Professional Engineers Association
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• v.45 no.1
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• pp.45-48
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• 2012

The 2011 Japan Tsunami caused tremendous damage to coastal areas. Because of their drastic propagation speed and large run-up height, nearshore tsunami can cause catastrophic damages on coastal communities within a short time. It is necessary to establish the tsunami hazard mitigation to reduce human injury housing damage. The construction of Tsunami warning system and production of hazard map are needed for minimizing damage by tsunami.