• Advances in concrete construction
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• v.6 no.5
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• pp.485-507
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• 2018

Concrete-Filled Steel Tube (CFST) columns are an increasingly popular means to support great compressive loads in buildings. The residual strength capacity of CFST stub columns may be utilized to assess the potential damage caused by fire and calculate the structural fire protection for least post-fire repair. Ten specimens under room conditions and 10 specimens under fire exposure to the Eurocode smouldering slow-growth fire were tested to examine the effects of diameter to thickness D/t ratio and reinforcing bars on residual strength capacity, ductility and stiffness of CFST stub columns. On the other hand, in sixteen among the twenty specimens, three or six reinforcing bars were welded inside the steel tube. The longitudinal strains in the steel tube and load-displacement relationships were recorded throughout the subsequent compressive tests. Corresponding values of residual strength capacity calculated using AISC 360-10 and EC4 standards are presented for comparison purposes with the experimental results of this study. The test results showed that after exposure to $750^{\circ}C$, the residual strength capacity increased for all specimens, while the ductility and stiffness were slightly decreased. The comparison results showed that the predicted residual strength using EC4 were close to those obtained experimentally in this research.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.155-161
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• 2019

Recently, increases in major disasters such as fires, earthquakes and typhoons have raised public expectations for safety. In addition to this increase in expectations of safety, the government continues to push for more manpower and better treatment for firefighters who are operating in the disaster scene. Despite the improvement of working conditions and increased welfare for firefighters, however, the incidence and turnover of various mental diseases continues to increase. It is reported that many of the diseases such as post-traumatic stress disorder and the turnover of firefighters are due to a mismatch in individual's personality and work environment. In this study, 108 firefighters were evaluated for their vocational aptitude in the new curriculum. Based on the analysis results, new firefighters were proposed to provide employment and education training improvements, and to provide job security suitable for the individual's personality type through the introduction of the vocational aptitude test for firefighters who are working in the fire service. In addition, we would like to use the vocational aptitude test as a material for reducing post-traumatic stress disorder and increasing turnover through long-term tracking and observation, rather than from a one-off perspective.

• Journal of Forest and Environmental Science
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• v.36 no.4
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• pp.298-310
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• 2020

Fuel management can play enormous role in fire management in tropical dry forests. However, unlike the temperate forests, knowledge on implications of different fuel management methods in tropical forests is often inadequate. In this study, the implications of prescribed burning and hand thinning treatments on implementation cost, fuel loading and post-treatment fire behaviour were tested and compared in degraded forests and teak plantations in two forest reserves of different levels of dryness in Ghana. The study found that prescribed burning was less expensive (62.02 US Dollars ha-1) than hand thinning (95.37 US Dollars ha-1). The study also indicated that the two fuel management methods were able to reduce fuel loading in degraded forests and teak plantations. However, prescribed burning was more effective in reducing fuel loading than hand thinning. While the relative change of fuel reduction was 13% higher in prescribed burning than the hand thinning in degraded forest, it was 41% higher in prescribed burning than hand thinning in teak plantations. The fire behaviour of post-treatment experimental fire was also lower in prescribed burning than the hand thinning and control plots. Fuel management, therefore, has a great potential in fire management in degraded forests and teak plantations in Ghana.

• The Korean Journal of Emergency Medical Services
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• v.11 no.3
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• pp.5-15
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• 2007

The purpose of this study was to identity the distribution of post-traumatic stress types and coping methods and to find the relationship between the post-traumatic stress types and the coping methods, for firefighters who experienced in Dea-Gu Subway Fire Disaster. The Subjects of this study were 126 firefighters who experienced Deagu Subway Disaster. Q questionnaire developed by Q-study and coping methods instrument based on that of Folkman & Lazaruswas revised and complemented by Kim Jung Hee was used. Data were analyzed by t-test, ANOVA using SPSS. The results of this study were as follows : 1. The distribution of post-traumatic stress types were 52.4% of Emotional arousal trauma, 34.1% of Trauma experience persistence and 13.5% of Physiological symptom experience. 2. The difference of post-traumatic stress types according to the general characteristics were significantly related to the physical injury(p = .010). 3. The minimum score of coping with post-traumatic stress types was 0.07, the maximum was 2.96 and the mean score was 1.27. 4. The coping methods according to the general characteristics were significantly different at active coping method according to educational level(p = .001), passive coping method according to educational level(p = .003) and passive coping method according to diagnosis(p = 0.20). 5. The mean score of active coping method according types were Emotional arousal trauma(1.505), trauma experience persistance(1.322) and Physiological symptom experience(1.276). The mean score of passive coping method related with types were Emotional arousal trauma(1.328), trauma experience persistance(1.254) and Physiological symptom experience(1.219).

• Journal of the Korea Concrete Institute
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• v.29 no.2
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• pp.217-223
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• 2017

This research was planned to evaluate the structural performance of post tensioned(PT) concrete member subjected to fire. Prime objective was to suggest some techniques to evaluate the performance of post tensioned concrete beam and slab exposed to high temperature through experiment. To accomplish this objective, the following two scopes have been proceeded to verify the strength reducing ratio of strands and find out the difference of resisting force at the PT concrete members exposed to high temperature through the fire test. The properties of prestressing steel(tendon) in PT concrete beam and slab under variable temperatures were reviewed. The test of this study was shown that stress relaxation occurred at high temperature, and some restoration of tensional force appeared as it got cooling down. The residual tension of the post tensioned beams at 4 hours after reaching the target temperature were 70% at $400^{\circ}C$, 10% at $600^{\circ}C$ and 2% at $800^{\circ}C$. The post tensioned slabs were 94% at $400^{\circ}C$, 84.5% at $600^{\circ}C$ and 62% at $800^{\circ}C$. The reason why the residual tension loss of the post tensioned slab was relatively small was considered to be that the slab was exposed just one side to high temperature and the strength of the strand was restored larger than that of beam. Also, it was confirmed that the post tensioned member inevitably experienced the loss of strength by fire damage, and restoration design of the member should be required to compensate for the value as much as lost strength.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.80-92
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• 2007

Forest fire is the dominant large-scale disturbance mechanism in the Korean temperate forest, and it strongly influences forest structure and function. Moreover burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. Vegetation rehabilitation may specifically vary according to burn severity after fire. To understand burn severity and process of vegetation rehabilitation at the damaged area after large-fire is required a lot of man powers and budgets. However the analysis of burn severity in the forest area using satellite imagery can acquire rapidly information and more objective results remotely in the large-fire area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. For classifying fire damaged area and analyzing burn severity of Samcheok fire area occurred in 2000, Cheongyang fire in 2002, and Yangyang fire in 2005 we utilized Normalized Burn Ratio(NBR) technique. The NBR is temporally differenced between pre- and post-fire datasets to determine the extent and degree of change detected from burning. In this paper we use pre- and post-fire imagery from the Landsat TM and ETM+ imagery to compute the NBR and evaluate large-scale patterns of burn severity at 30m spatial resolution. 65% in the Samcheok fire area, 91% in the Cheongyang fire area and 65% in the Yangyang fire area were corresponded to burn severity class above 'High'. Therefore the use of a remotely sensed Differenced Normalized Burn Ratio(${\Delta}NBR$) by RS and GIS allows for the burn severity to be quantified spatially by mapping damaged domain and burn severity across large-fire area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3815-3823
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• 2013

The purpose of this study was to closely examine the influence of field-shock experience and post traumatic stress perceived by fire officials upon somatic symptoms and coping methods. A survey was carried out targeting 362 male and female fire officials who are working at fire safety centers where are located in Gangwon-do Province. The collected data were used SPSS 19.0 and AMOS 19.0 for Windows. It carried out frequency analysis, factor analysis for validity and reliability, Cronbach's ${\alpha}$ analysis, descriptive statistics and correlation. For hypothesis verification, an analysis was carried out by using structural equation modeling. All the statistical analyses were set for the significant level in p<.05. The results are as follows. First, the perceived field-shock stress was indicated to have influence upon post traumatic stress. Second, the perceived field-shock stress was indicated to have influence upon somatic symptom. Third, the perceived field-shock stress was indicated to have influence upon a coping method. Fourth, the post traumatic stress was indicated to have influence upon somatic symptom. Fifth, the post traumatic stress was indicated to have influence upon a coping method. Sixthly, the somatic symptom was indicated to have influence upon a method of coping with stress.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.2
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• pp.150-156
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• 2015

In this study, the effects of different mix proportions and fire scenarios (exposure temperatures and post-fire-curing periods) on fire-damaged concrete were analyzed using a nonlinear resonance vibration method based on nonlinear acoustics. The hysteretic nonlinearity parameter was obtained, which can sensitively reflect the damage level of fire-damaged concrete. In addition, a splitting tensile strength test was performed on each fire-damaged specimen to evaluate the residual property. Using the results, a prediction model for estimating the residual strength of fire-damaged concrete was proposed on the basis of the correlation between the hysteretic nonlinearity parameter and the ratio of splitting tensile strength.

• Journal of the Korea Institute of Building Construction
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• v.14 no.2
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• pp.143-149
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• 2014

Recently, the structure system for apartment buildings in Korea has been changing from wall to post-beam structure. This study examines the fire resistance and sound insulation of light-weight dried wall, a component of post-beam structure. For the fire resistance and sound insulation in Korea, the Compartment wall of apartment house in the case of building regulation has regulations specify the detailed requirement of fire compartment walls in apartment, but do not specify that of interior walls. This study proposes the fire resisting rate of the interior wall into three grades in which the highest grade requires fire resistance of 30 minutes and also proposes the requirement of sound insulation performance into three grades in which the lowest grade requires 35dB.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.385-390
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• 2023

The purpose of this study is to study the need for psychological first aid for stress of fire officials. a 1:1 in-depth interview with 10 paramedics to solve the research problem. Through interviews, the policy on the need for psychological first aid to improve the mental health of firefighters was proposed as follows by analyzing the working environment of paramedics, post-traumatic stress experience, and psychological first aid experience. First, fire officials need to be assigned to the site to educate in advance about post-traumatic stress and the resulting physical symptoms before being exposed to traumatic events. Second, fire officials should provide psychological first aid at an appropriate time after exposure to trauma cases. Third, it is necessary to supplement the manpower and institutional devices that will specialize in mental health work. Fourth, for customized professional medical services and psychological support suitable for fire officials, it is necessary to link fire-fighting complex healing centers and national firefighting hospitals.