• Fire Science and Engineering
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• v.30 no.5
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• pp.124-129
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• 2016

According to the current law, on-site flame resistant-treated interior decorations should pass the flame resistant performance test through a 45 degree combustion test from the district fire department. Although a 45 degree combustion test is the most accurate method for determining the flame resistant performance, it can be unreliable when tested on unauthorized samples. To avoid unauthorized sampling, this study suggests on-site flame resistant inspection by X-ray fluorescence spectrometer. Ten types of flame resistant paint were spread on plywoods and MDFs and the components were analyzed by X-ray fluorescence spectrometer. As a result, due to a difference amounts of substances in each paint, each flame resistant paints showed its own characteristic spectrum and the contents of each substance could be determined. On-site flame resistant inspections can be used efficiently when institutional procedures are created.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.11B
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• pp.1738-1747
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• 2010

This report shows the analysis and design of tactical decision automation procedure and the result of core algorithm. Expecially scheme of analysis and design includes result of tactical decision supporting procedure analysis for target engagement to fire in refer to AFATDS. Tactical decision automation procedure has three phases like target analysis, target priority, fire unit decision, fire method and attack method. Target analysis creates base information to decide priorities and attack methods through target activity, size and protection status. Target priority and fire unit decision judge target priority and fire unit with unit status and operation mission basis of target priority. Fire unit and Attack method decide fire style according to the kind of fire and ammunition for effective firing achievement. Finally, we show the effective tactical decision automation procedure through making the algorithm of priority and air control.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.8
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• pp.579-588
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• 2013

This paper proposes an effective watermarking approach for copyright protection of fire video images. The proposed watermarking approach efficiently utilizes the inherent characteristics of fire data with respect to color and texture by using a gray level co-occurrence matrix (GLCM) and fuzzy c-means (FCM) clustering. GLCM is used to generate a texture feature dataset by computing energy and homogeneity properties for each candidate fire image block. FCM is used to segment color of the fire image and to select fire texture blocks for embedding watermarks. Each selected block is then decomposed into a one-level wavelet structure with four subbands [LL, LH, HL, HH] using a discrete wavelet transform (DWT), and LH subband coefficients with a gain factor are selected for embedding watermark, where the visibility of the image does not affect. Experimental results show that the proposed watermarking approach achieves about 48 dB of high peak-signal-to-noise ratio (PSNR) and 1.6 to 2.0 of low M-singular value decomposition (M-SVD) values. In addition, the proposed approach outperforms conventional image watermarking approach in terms of normalized correlation (NC) values against several image processing attacks including noise addition, filtering, cropping, and JPEG compression.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.38-50
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• 2022

Purpose: The goal of this research is to create a numerical analytic database that may assist fire prevention managers and building officials in prioritizing items that need to be addressed in order to improve evacuation safety performance while working within a constrained budget and time frame. Method: It was carried out utilizing the CFD Tool, a quantitative evaluation approach, to assess evacuation safety. One direct staircase-type apartment houses and one corridor-type apartment were chosen to make it. Result: In the fire compartment category, Apartment A's evacuation time was around 130 percent longer than that of sprinkler facilities. Conclusion: Fire prevention managers and building officials feel that starting with a single level and implementing "dwelling unit separations" will increase evacuation safety, and that maintaining fire compartments and sprinkler systems at all times will be effective. Because of the limited characteristics of smoke propagation in corridor-type apartments compared to direct staircase-type flats, it is thought that fire extinguishing equipment should be addressed.

• Fire Science and Engineering
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• v.28 no.3
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• pp.49-54
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• 2014

Beams play an important role to transfer an applied load on the floor into columns. However, if the beams affected by a fire the length will be changed longer or shorter and the structural stability decreased gradually and resulted in structural failure. Therefore, the fire regulation requires that structural beam has to satisfied with a constant fire resistance. The fire resistance conducted by a constant size and boundary condition in an horizontal furnace. But this is not enough to adopt a beam made of high structural steels having various lengths. In this study, in order to suggest structural behaviors of beams made of high structural steels at high temperature, mechanical properties at high temperature and heat stress analysis were used and the surface temperature, expansion, displacement and variance of maximum load according to lengths of the beam were compared with those of SM 400.

• Journal of the Korean Society of Hazard Mitigation
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• v.1 no.1 s.1
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• pp.157-163
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• 2001

The objective of the present study is to predict the characteristics of the fire and smoke propagations in a clean room. Numerical calculations have been performed by using the finite volume method to obtain temperature and velocity distributions in the clean room. In odor to account for the turbulent flow characteristics, the standard $k-{\varepsilon}$ model is used. From this study, it was found that the fire propagation could be fully developed only after 150 seconds when the ventilation system in the clean room was off. And the smoke mass fraction showed a similar distribution as the gas temperature. Since the simulated fire was proceeded up to $20{\sim}30%$ of the room within 60 seconds. it could be recommended that the occupants should be evacuated from the room within 30 seconds.

• Fire Science and Engineering
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• v.34 no.2
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• pp.156-165
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• 2020

In this paper, the application of evacuation delay time (Cognition time + initiation time) and examine the degree of opening of fire doors in households for evaluating evacuation safety and suggest a realistic alternative. In order to proceed with this study, first of all, the preliminary investigation on evacuation safety evacuation of residential-type buildings (Apartment, urban living houses, etc.) among the performance-oriented design targets of Gwangju Metropolitan City, which was implemented until June 2018. Then, for the two representative types that are commonly used among the previously surveyed buildings, evacuation delay time is applied to W1, W2, and respectively simulating the opening of the doors is applied to th full open, 1/4 open, the leakage gap and evacuation safety evaluation was performed. As a result of evaluating evacuation safety was found that it is difficult to secure evacuation safety regardless of evacuation delay time W1 and W2 when the fire door is fully open and 1/4 open, Only when the leakage gap is applied evacuation safety was ensured even if evacuation delay time W2 was applied. Therefore, when a residential building is subject to performance-oriented design, evaluating the application of W2 rather than W1 is considered for evacuation delay time to reflect concern about privacy infringement due to CCTV installation, etc. In order to secure the Smoke blocking performance of the fire door and to improve the performance-oriented design, I would like to propose to consider the method of applying a leak gap to the degree of opening of the fire door. Through this, it is expected that the performance-oriented design will be a step further by performing evacuation safety evaluation with more realistic data.

• Fire Science and Engineering
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• v.25 no.6
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• pp.136-145
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• 2011

One of a large proportion among the causes of fire is electrical factors, and of fire by electric factors, the accident which accounted for over certain percentage is electric leakage and ground fault. In order to reduce the electric leakage and ground fault, the technical guidelines on the protection of ground fault in the low-voltage electrical line (KECG 1091-2011) was amended for reflecting recent international standard, IEC 60364-4-41, and new conservation methods, which improved the reliability by recovering the facility's all-time use operation and breakdown defect, was on the rise. Accordingly, in this paper, after grasping the fire's status for last 10 years and analyzing the risk of electrical fires, and as a way to improve the electric leakage and ground fault accident which accounted for more than certain percentage, the revision of KECG 1091-2011 will be reviewed. And then, after applying to the preventive conservation methods in order to enhance the protection reliability of electric leakage and ground fault detection, the problems at issue routine inspection scheme and durable years scheme in time-scheduled conservation method are listed, along with suggestion of the problem-solving scheme, and the leakage current integrated monitoring systems and digital electric leakage devices by status monitor conservation method will be proposed.

• Korean Journal of Construction Engineering and Management
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• v.9 no.5
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• pp.186-193
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• 2008

The SPS, Strut as a Permanent System, method is widely adopted for the main structural member in addition to temporary strut function for the shuttering of excavation work. Although the SPS method has contributed to cost saving, time reduction, enhancement of structural stability, improvement of construction environment and so on at the building construction site, it caused the problems of increase of basement height and additional work for fire protection of steel structure. The increase of basement height caused the increase of shuttering depth and excavation, and the fire protection caused the additional cost as well as the deterioration of construction environment. In order to improve the problems, this paper is to propose a modularized hybrid structural system(HSD). The detail of the system is introduced and the structural performance and constructibility are proved through the experiment and site application.

• Fire Science and Engineering
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• v.29 no.2
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• pp.33-38
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• 2015

For the purpose of high-pressure and suction of fixed amount, the development of ultra-high pressure rotating helical gear positive displacement pump with no clearance had been proceeded. The CFD analysis was performed to verify the internal pressure and the discharge flow velocity of the pump. Accordingly, a flow analysis were performed by FVM technique and we were unable to obtain a successful result since the fluid domain is separated because the grid is not configured in a row in FVM flow analysis of the fully enclosed type without clearance. Because of these problems, the flow analysis was performed by MPS method which grid configuration is not needed and the internal pressure and the discharge flow velocity of the pump were confirmed through the MPS flow analysis. At 1,000 rpm rotation speed of the rotor, the minimum internal pressure of the pump was 19.5 bar, maximum pressure was 44.6 bar and average pressure was 33.9 bar. And the minimum discharge flow velocity was 64.5 m/s, maximum discharge flow velocity was 84.8 m/s and average discharge flow velocity was 76.1 m/s. Through this study, we could confirm that MPS method was more suitable than FVM method in terms of flow analysis with no clearance. In addition, the relationship of the flow velocity according to the change of ultra-high pressure rotating helical gear positive displacement pump could be identified through this study.