• Journal of the Semiconductor & Display Technology
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• v.17 no.3
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• pp.95-99
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• 2018

In this study, take a look at natural disasters and technical characteristics such as frequency, bandwidth, transmission power, and service coverage of mobile communication and terrestrial broadcasting are compared as a means to provide disaster warning service in case of natural disaster, which is increasing in recent years. In the event of a disaster, mobile communication systems that take high frequency bands, low power transmission and narrow coverage can be disabled, but terrestrial broadcasting, which uses VHF and UHF with good frequency characteristics and high transmission power and wide service coverage provides stable services. As result terrestrial broadcast is useful as emergency warning or information in case of disaster.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.319-322
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• 2007

This study aims to find the characteristics of damage and states of natural disasters at the Korean Peninsula from 1985 to 2004. Using the data of Statistical yearbook of calamities issued by the National Emergency Management Agency and Annual Climatological Report issued by the Korea Meteorological Administration. we have analyzed the cause, elements, and vulnerable regions for natural disasters. Major causes of natural disaster at Korean Peninsula are four, such as a heavy rain, heavy rain typhoon, typhoon, storm snow, and storm. The frequency of natural disaster is the highest from June to September. The period from December to March also shows high frequency. The total amount of damage is high during the summer season(Jul.-Sept). The period from January to March shows relatively high amount of damage due to storm and storm snow The areas of Gangwon-do, Gyeongsangnam-do and Gyeongsangbuk-do are classified the vulnerable region for the natural disasters. By establishing mitigation plans which fit the type and characteristics of disaster for each region, damage from disaster can be reduced with efficient prevention activities.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.277-280
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• 2008

Enhancing the positioning precision is the primary pursuit of GPS users. To achieve this goal, most studies have focused on the relationship between GPS receiver clock errors and GPS positioning precision. This study utilizes undifferentiated phase data to calculate GPS clock errors and to compare with the frequency of cesium clock directly, thus verifying estimated clock errors by the method used in this paper. The relative frequency offsets from this paper and from National Standard Time and Frequency Laboratory of Taiwan match to $1.5{\times}10^{12}$ in the frequency instability, suggesting that the proposed technique has reached a certain level of quality. The built-in quartz clocks in the GPS receivers yield relative frequency offsets that are 3 to 4 orders higher than those of rubidium clocks. The frequency instability of the quartz clocks is on average two orders worse than that of the rubidium clock. Using the rubidium clock instead of the quartz clock, the horizontal and vertical positioning accuracies were improved by 26-78% (0.6-3.6 mm) and 20-34% (1.3-3.0 mm), respectively, for a short baseline. These improvements are 7-25% (0.3-1.7 mm) and 11% (1.7 mm) for a long baseline. Our experiments show that the frequency instability of clock, rather than relative frequency offset, is the governing factor of positioning accuracy.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.493-504
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• 2020

Purpose: The purpose of this study is to propose an analytical methodology for selecting the priority of preventive projects in the course of carrying out disaster prevention projects that improve disaster-hazardous areas. Method: Data analysis was performed using RFM model which can divide data grade and perform target marketing based on Recency, Frequency, and Monetary. Result: The top 10% of the area with high RFM value was mainly in the East Sea and the South Sea coast, and the number of damage in private facilities was high. Conclusion: In this study, we used the RFM model to select the priority of disaster risk and to implement the regional disaster risk using GIS. These results are expected to be used as basic data for selecting priority project sites for disaster prevention projects and as basic data in the decision-making process for disaster prevention projects.

• Structural Engineering and Mechanics
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• v.81 no.6
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• pp.691-703
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• 2022

To obtain the seismic response of lead-cored rubber, shape memory alloy (SMA)-rubber isolation Plate-shell Integrated Concrete Liquid-Storage Structure (PSICLSS), based on a PSICLSS in a water treatment plant, built a scale experimental model, and a shaking table test was conducted. Discussed the seismic responses of rubber isolation, SMA-rubber isolation PSICLSS. Combined with numerical model analysis, the vibration characteristics of rubber isolation PSICLSS are studied. The results showed that the acceleration, liquid sloshing height, hydrodynamic pressure of rubber and SMA-rubber isolation PSICLSS are amplified when the frequency of seismic excitation is close to the main frequency of the isolation PSICLSS. The earthquake causes a significant leakage of liquid, at the same time, the external liquid sloshing height is significantly higher than internal liquid sloshing height. Numerical analysis showed that the low-frequency acceleration excitation causes a more significant dynamic response of PSICLSS. The sinusoidal excitation with first-order sloshing frequency of internal liquid causes a more significant sloshing height of the internal liquid, but has little effect on the structural principal stresses. The sinusoidal excitation with first-order sloshing frequency of external liquid causes the most enormous structural principal stress, and a more significant external liquid sloshing height. In particular, the principal stress of PSICLSSS with long isolation period will be significantly enlarged. Therefore, the stiffness of the isolation layer should be properly adjusted in the design of rubber and SMA-rubber isolation PSICLSS.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.6
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• pp.3-12
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• 2019

Current risk assessment methods typically determine accident risks embedded in construction projects by combining severity and frequency; however, they do not reflect the characteristics of construction projects. To solve the problem, this study aims to develop a novel risk assessment method that combines severity, frequency, and disaster influence factors (i.e., weather conditions and worker's characteristics) for assessing risks of activities occurring on a construction site actually. In this study, a severity was estimated by death against victims, and a frequency was estimated by the victim rate. The frequency was then converted to probability taking disaster influence factors into account. Thus, instead of considering severity and frequency for assessing the original risks (RO), the proposed method uses severity and probability to yield adjusted risks (RA) for each activity. A case study was conducted to determine if the proposed method works as intended in a real setting. The results show that RA is more sensitive to disaster influence factors than RO and, therefore, is able to assess the actual risks reflecting the working environment and conditions of a construction site. This study contributes to risk management of construction projects by offering a risk assessment method that measures a possibility of potential disasters from the probabilistic perspective. This method would help project managers assess accident risks in a more systematic and quantitative manner.

• Journal of the Society of Disaster Information
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• v.20 no.2
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• pp.462-469
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• 2024

Purpose: This study aims to analyze data on disaster safety education for migrant youth and to examine the corresponding social perceptions. Method: Data on disaster safety education for migrant youth were collected and analyzed using Textom and Ucinet. The data used in the study were searched on portal websites from 2016 to 2023 using the keywords 'migrant youth+ disaster + safety education'. Result: The analysis results showed that 'education (306)' had the highest frequency, followed by 'safety (287)', 'school (97)', 'society (85)', and 'support (77)'. The keyword with the high degree of centrality, closeness centrality, and betweenness centrality were 'education', 'safety' and 'society'. 'Family' ranked higher in betweenness centrality than the rankings of frequency analysis, degree centrality and closeness centrality, indicating that 'family' plays a significant role as a mediator in the network of disaster safety education for migrant youth. Conclusion: By examining social awareness about disaster safety education for migrant youth, the findings will be used to develop policies and strategies for disaster safety education that consider the unique vulnerabilities of migrant youth in disaster situations.

• The Korean Journal of Emergency Medical Services
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• v.23 no.2
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• pp.19-31
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• 2019

Purpose: This study aimed to investigate disaster preparedness competence and disaster response competence of paramedics working in emergency medical centers operating a disaster medical assistance teams. Methods: Data of 174 emergency medical technician(EMT)-paramedics were collected from July 15 to August 14, 2018 at regional and local emergency medical centers that operate disaster medical assistant team. Analysis of the data was carried out with IBM SPSS statistics 24.0 software (IBM, Armonk, NY, USA). Results: The mean disaster preparedness competence score was $3.57{\pm}0.63$ (out of five). Participants' disaster preparedness competence significantly differed according to type of emergency medical center (p<.000), disaster education experience (p<.000), and education frequency (p=.001). The mean disaster response competence score was $4.09{\pm}0.57$ (out of five). Participants' disaster response competence significantly differed according to disaster education experience (p<.000) and medical assistance experience (p=.045). Conclusion: Emergency medical technician-paramedics without disaster training should first be provided with this training. Further, it is important for EMT-paramedics to know their disaster preparedness and response capacities and strengthen their shortcomings. It is also important to develop education and training programs that properly equip EMT-paramedics with practical competencies.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.97-113
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• 2018

Low-frequency geological natural disaster events such as Pohang earthquake have been occurred. As a results, there's a growing recognition on the importance of education and training for low frequency geological disasters in Korea. In spite of many years of scientific researches on volcanic disaster prevention and preparedness on Baekdusan volcano, the results do not provide the proper scenario for the training for volcanic ash event. Fall 3D volcanic ash diffusion model was run based on wind field data for the last five year, assuming Aso Mountain's explosion with volcanic explosion index 5 for seventy two hours. The management criteria values for proper actions in the previous studies were applied to make a scenario for thirteen groups of the disaster response teams such as train transportation, water supply, electrical facilities and human health. The models on the relationship between education and training for disaster prevention and response were suggested to fulfill the scientific and practical training at local level.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.181-190
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• 2016

Improvements in disaster management has become a global necessity because the magnitude of disasters is intensifying in parallel with the increased disaster damage. The disaster risk in Korea is also increasing due to the emergence of new types of disaster; such as the Middle East respiratory syndrome coronavirus, the increase of complex disasters, and the heightened probability of a catastrophic event due to climate change. This paper aimed to identify the disaster loss-frequency relationship from 1948 to 2014 in Korea by using four types of variables. In addition, this paper found major disasters that resulted in the reformation of disaster response organizations, and inputted the deaths and economic loss attributed to those disasters into the disaster loss-frequency graph. The research result substantiated that the disaster loss-frequency relationship in Korea follows the Power Law and found the coefficients of each Power Function. Additionally, this paper found that most of the reformations of disaster response organizations happened after major disasters that concentrated societies attention and anger due to the high human and economic impact; such events are labelled as "focusing events." These focusing events, with the characteristics of a low probability and high impact, are located in the long tail of the Power Law Distribution. This paper suggests that the effective public policy for disaster response needs to be developed by paying attention to 'low probability and high impact' focusing events that are located in the long tail of the Power Law Distribution.