• Title/Summary/Keyword: Fires

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A Numerical Study on Smoke Movement in Longitudinal Ventilation Tunnel Fires Using a Zone Model (존 모델을 이용한 종류식 배연 터널 화재시 연기 거동에 대한 수치해석적 연구)

  • Kim, Hyun-Jeong;Roh, Jae-Seong;Kim, Dong-Hyeon;Jang, Yong-Jun;Ryou, Hong-Sun
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1319-1324
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    • 2007
  • Many researches have been performed to analyze the smoke movement in tunnel fires by using field model. Recently, FDS(Fire Dynamics Simulator) v.4, which is one of the field model and developed from NIST(National Institute of Standards and Technology), is widely used. In tunnel fires, FDS can show detail results in local point, but it has difficulties in boundary condition and taking long computing time as the number of grid increases. So, there is a need to use alternative method for tunnel fire simulation. A zone model is different kind of CFD method and solves ordinary differential equation based on conservation and auxiliary equations. It shows good macroscopic view in less computing time compared to field model. In this study, therefore, to confirm the applicability of CFAST in tunnel fire analysis, numerical simulations using CFAST are conducted to analyze smoke movement in longitudinal ventilation reduced-scale tunnel fires. Then the results are compared with experimental results. The differences of temperature and critical velocity between numerical results and experimental data are over $30^{\circ}C$ and 0.9m/s, respectively. These values are out of error range. It shows that CFAST 6.0 is hard to be used for tunnel fire simulation.

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Forest Environment Monitoring Application of Intelligence Embedded based on Wireless Sensor Networks

  • Seo, Jung Hee;Park, Hung Bog
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.4
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    • pp.1555-1570
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    • 2016
  • For monitoring forest fires, a real-time system to prevent fires in wider areas should be supported consistently. However, there has still been a lack of the support for real-time system related to forest fire monitoring. In addition, the 'real-time' processing in a forest fire detection system can lead to excessive consumption of energy. To solve these problems, the intelligent data acquisition of sensing nodes is required, and the maximum energy savings as well as rapid and accurate detection by flame sensors need to be done. In this regard, this paper proposes a node built-in filter algorithm for intelligent data collection of sensing nodes for the rapid detection of forest fires with focus on reducing the power consumption of the remote sensing nodes and providing efficient wireless sensor network-based forest environment monitoring in terms of data transmission, network stability and data acquisition. The experimental result showed that battery life can be extended through the intelligent sampling of remote sensing nodes, and the average accuracy of the measurement of flame detection based on the distance is 44%.

The Design and Implementation of Mobile Application Solution for Forest Fire based on Drone Photography and Amazon Web Service (AWS)

  • Choi, Si-eun;Bang, Jong-ho
    • Journal of Internet Computing and Services
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    • v.21 no.5
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    • pp.31-37
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    • 2020
  • Last year's Goseong-Sokcho forest fires have highlighted the limitations of extinguishing work for night-time forest fire and the importance of quick identification for information on the spread of forest fire. However, it is not easy to find services that take into account the characteristics of forest fires, as most existing disaster-related mobile applications and research assume various disaster situations rather than just forest fire situations. Therefore, a system that can provide information quickly is needed, taking into account the characteristics of forest fires and the limitations of extinguishing work. In this paper, we propose evacuation route guidance services that bypass areas where fire has already spread, supplement existing methods of extinguishing work, and provide general information on forest fire situations in real time, by putting drones into forest fire situations. It has been implemented to automate image analysis using the Rekognition service of Amazon Web Service (AWS), and the results of fire detection and the T Map API guide the evacuation path. It is expected that the results of this paper will allow efficient and rapid rescue and extinguishing work to be carried out, and further reduce the damage of human life caused by forest fires.

Electric Fire Prediction by Detection of Discharge Signal (방전신호 검출에 의한 전기화재 예측)

  • 길경석;송재용;권장우
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.413-419
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    • 2004
  • This paper describes a technique that can predict electric fires by detection of discharge voltage signals caused by the use of electric facilities. In the experiment, various discharge modes, a flashover or a surface discharge through insulation paper and a line to line short, were simulated to acquire electrical information for predicting electrical fire as discharge modes. From the experimental results, it is hewn that electorial discharges which are ranked as majority causes of electric fires generate characterized signals distinguished from power frequency. Finally. We designed a prototype discharge detector based on the experimental results, and the detector is applied to a power lines. This study showed that the prediction of electric fires is possible by monitoring discharge voltage signals in electric power lines.

The Implementation of the system-on-board controllable the electrical fires due to ground fault, arc fault and overload (누전, 아크, 과부하에 의한 전기화재 제어 시스템 보드의 구현)

  • Kim, Byung-Cheul;Chun, Joong-Chang
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.2
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    • pp.419-424
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    • 2011
  • The system-on-board detectable and controllable the electrical fires due to ground fault(GF), arc fault and overload is implemented. The system IC for controlling and preventing the electrical fires is available to this system. The GF detection circuit for detecting the electrical leakage current, the arc fault detection circuit and the overload detection circuit controllable the input voltage for flowing the overload current are designed. The GF detection circuit and the arc fault detection circuit are good operated to the electrical leakage current and the arc signal, respectively. It is confirmed that the overload detection circuit has shown no erratic operation with the noise or the load variation and is only operated at the overload condition.

EXPERIMENTS ON THE INTERACTION OF WATER SPRAYS WITH POOL FIRES

  • Han, Yong-Shik;Kim, Myung-Bae;Shin, Hyun-Dong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.518-525
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    • 1997
  • A series of measurements and visualization to investigate the interaction of water sprays with pool fires is presented. Fire source is a small-scale pool burner with methanol, ethanol and gasoline. Measurements of temperatures, $O_2$, $CO_2$, and CO concentrations along the plume centerline are carried out to observe pool fire structures without water sprays. Visualization by the Ar-ion laser sheet shows flow pattern of droplets of the sprays above the pool fires. It is observed that in the case of methanol and ethanol, water sprays continuously penetrate into the center of fuel surfaces. The gasoline pool fire allows intermittent penetration of water sprays because of pulsating characteristics of the gasoline flame. To evaluate the cooling effect of the fuel surface by the sprays, the temperature was measured at the fuel surface. As soon as the mists reach the fuel surface of methanol and ethanol, the temperatures of the fuel surface decrease rapidly below the boiling point, and then the fires are extinguished. Due to the application of mist upon the gasoline fire, though the fuel temperature decrease abruptly at the time of the injection, such a rapid decrease do not continue till the extinction point.

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A FORECASTING METHOD FOR FOREST FIRES BASED ON THE TOPOGRAPHICAL CLASSIFICATION SYSTEM AND SPREADING SPEED OF FIRE

  • Koizumi, Toshio
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.311-318
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    • 1997
  • On April 27,1993, a forest fire occurred in Morito-area, Manba-city, Gunma-prefecture Japan. Under the prevailing strong winds, the fire spread and extended to the largest scale ever in Gunma-prefecture. The author chartered a helicopter on May 5, one week after the fire was extinguished, and took aerial photos of tile damaged area, and investigated the condition. of the fire through field survey and data collection. The burnt area extended. over about 100 hectares, and the damage amounted to about 190 million yen (about two million dollar). The fire occurred at a steep mountainous area and under strong winds, therefore, md and topography strongly facilitated the spreading, It is the purpose of this paper to report a damage investigation of the fire and to develop the forecasting method of forest fires based on the topographical analysis and spreading speed of fire. In the first place, I analyze the topographical structure of the regions which became the bject of this study with some topographical factors, and construct a land form classification ap. Secondly, I decide the dangerous condition of each region in the land form classification map according to the direction of the wind and spreading speed of f'kre. In the present paper, I try to forecast forest fires in Morito area, and the basic results for the forecasting method of forest fires were obtained with the topographical classification system and spreading speed of fire.

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Design and Implementation of UV Flame Detector Module Using Low Power Algorithm of ZigBee (ZigBee Protocol의 저 전력 알고리듬을 이용한 UV Flame Detector의 설계 및 구현)

  • Lee, Young-Jae;Chang, Choong-Won;Rhee, Sang-Yong;Jung, Min-Su
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.3
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    • pp.429-436
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    • 2008
  • Nowadays fires must be detected rapidly Abstract, and by connecting the detector's distribution, sender, transponder, receiver and others can be connected. Mechanical systems are implemented in today's buildings. However, this kind of constructing method has some disadvantages, that is, if fire happens somewhere, we cannot judge where the fires happen, and it is also difficult to judge what extent the fires reach. In order to overcome the disadvantages, in this paper, according to the tendency of combining the Ubiquitous and Intelligent Network, we propose a type of system by using the method of comparing the differences of the existed systems. The proposed system is designed to perceive the fires rapidly and confirm the fire place and fire scale correctly.

Implementation of Automatic Extinguishing System for fire suppression of vehicle (차량 화재 진압을 위한 자동 소화 시스템 구현)

  • Ryu, Hye-Yeon;Kim, Man-Ho
    • Journal of the Korean Society of Industry Convergence
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    • v.22 no.2
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    • pp.227-233
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    • 2019
  • In recent years, vehicle fires account for the second highest rate after residential fires. It accounts for more than 10.7% of the total fire occurrence rate. Vehicle fires are very difficult to evolve at an early stage. Most of the vehicles are burned down in the event of a fire, resulting in a lot of physical and personal damage. In the EU and other countries, efforts are being made to install automatic fire extinguishing systems in preparation for vehicle fires. In addition, since the automatic fire extinguishing system applied to a vehicle must operate in a moving state of a car, a method for detecting a fire is needed. Therefore, this paper proposes a structure of an automatic fire extinguishing system that can evolve a fire when a fire occurs in a commercial vehicle among various vehicles. Especially, it confirms the feasibility of the automatic fire extinguishing system simulated in the laboratory environment and confirms its applicability.

Numerical Study on the Fire Damaged Reinforced Concrete Building Structures Considering Influencing Fire Case and Parameters of Columns (화재피해를 받은 철근콘크리트 건축물의 기둥의 영향인자를 고려한 해석적 연구)

  • Suh, Yeonwoo;Son, Hee Ju
    • Journal of the Korean Society of Safety
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    • v.37 no.4
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    • pp.101-112
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    • 2022
  • Expanding urbanization practices result in high numbers of buildings being developed in city centers. This high building concentration leads to an increased fire risk, resulting in higher casualty rates and increased economic damages compared to fires in the past. The purpose of this study was to analyze the structural behavior of fire-damaged reinforced concrete buildings using analytical methods and to suggest methods of improving fire resistance in the event of a fire. Damage levels were measured using commercial software to apply the finite element method, ABAQUS, and MIDAS GEN to the dataset. Load-deflection curves were calculated using the effective area and moment of inertia of the fire-damaged columns provided by ABAQUS. The results of this analysis indicate that fire-damaged beams with experience greater deflection from indoor fires than they will from outdoor fires. Fires that occurred on the middle floors were more dangerous than those occurring on higher floors, and eccentrically loaded columns experienced more damage than axially loaded columns. The results indicate that these methods accurately predict structural behaviors of fire damaged concrete columns by considering fire exposure area and eccentric loading.