• Title/Summary/Keyword: Fire Modeling

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Predicting the Potential Distribution of an Invasive Species, Solenopsis invicta Buren (Hymenoptera: Formicidae), under Climate Change using Species Distribution Models

  • SUNG, Sunyong;KWON, Yong-Su;LEE, Dong Kun;CHO, Youngho
    • Entomological Research
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    • v.48 no.6
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    • pp.505-513
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    • 2018
  • The red imported fire ant is considered one of the most notorious invasive species because of its adverse impact on both humans and ecosystems. Public concern regarding red imported fire ants has been increasing, as they have been found seven times in South Korea. Even if red imported fire ants are not yet colonized in South Korea, a proper quarantine plan is necessary to prevent their widespread distribution. As a basis for quarantine planning, we modeled the potential distribution of the red imported fire ant under current climate conditions using six different species distribution models (SDMs) and then selected the random forest (RF) model for modeling the potential distribution under climate change. We acquired occurrence data from the Global Biodiversity Information Facility (GBIF) and bioclimatic data from WorldClim. We modeled at the global scale to project the potential distribution under the current climate and then applied models at the local scale to project the potential distribution of the red imported fire ant under climate change. Modeled results successfully represent the current distribution of red imported fire ants. The potential distribution area for red imported fire ants increased to include major harbors and airports in South Korea under the climate change scenario (RCP 8.5). Thus, we are able to provide a potential distribution of red imported fire ant that is necessary to establish a proper quarantine plan for their management to minimize adverse impacts of climate change.

A Study on the Performance Criteria of Smoke Control System for Underground Spaces Through Numerical Analysis (수치해석을 통한 지하공간의 제연설비 성능기준 검토)

  • Ahn, Chan-Sol;Chae, Han-Sic;Kim, Hyeung-Youl
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.356-362
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    • 2008
  • This study is intended to evaluate the characteristics of smoke spreading and the appropriateness of evacuation time extended by operation of smoke control system during fire within the underground space of the building structured in compliance with the smoke control system performance criteria from the local fire safety standard in Korea. As a preceding review of this study, the combustibles was categorized and identified their heat release rates. For validate the estimated values, modeling a single underground shop was carried out. And a numerical analysis both in case of smoke control system in operation and the system not in operation was carried out of underground space. From the viewpoint of securing the evacuation time, the results were compared in an attempt to assess the appropriateness of the fire safety criteria.

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A Study on basic theory in fire simulation using SOFIE (SOFIE를 활용한 화재 시뮬레이션에 관한 기초적 연구)

  • Lee, Jung-Hyun;Kim, Hak-Chul
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2012.04a
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    • pp.266-269
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    • 2012
  • 화재 시뮬레이션을 이용하면, 건축물에서 화재가 발생하는 경우 건물에 설치된 감지 시스템 및 자동식 소화설비 등의 작동 여부에 따라 건물 내부의 온도 변화, 산소 및 일산화탄소 농도 변화, 연기유동 현상 등 화재 안전에 관련된 요소를 확인, 분석이 가능하기 때문에 건물의 화재 안전성을 검증하는데 활용할 수 있고 방재시스템 설계 조건을 변경하여 반복 시뮬레이션을 실시함으로써 보다 효율성이 높은 방재 시스템을 설계 및 채택할 수 있다. 또한 화재 시뮬레이션 결과를 감안하여 유사시 효과적으로 대응할 수 있도록 방재계획을 수립할 수 있고, 건축물의 구조, 내장재 및 수용품에 대한 설계, 배치 등에 사용할 수 있으며, 화재사고조사 및 원인 규명에도 활용할 수 있는 등 화재 시뮬레이션의 활용분야는 광범위하다. 최근 국내에도 화재로 인한 인적/물적 피해와 화재 안전 설계에 대한 관심증가로 화재 모델에 대한 많은 연구가 이루어지고 있다. 그러나 대부분의 연구가 시뮬레이션을 이용한 결과 분석에 치중되어있고 화재 시뮬레이션에 관한 특성 연구 및 개발은 거의 이루어지지 않고 있다. 본 자료는 국내에서 화재 시뮬레이션 코드로 많이 알려지지 않았으며, 유럽에서 개발된 SOFIE(Simulation of Fire in enclosures)에 대해서 기초적인 연구를 수행하였으며, SOFIE에 대한 특정 문제나 평가 부분은 다루지 아니하였다.

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The Fire Dispersive Patterns of the Power Cord Sets for Low Voltage Appliances in Wall-modeling (벽면 모델링을 이용한 저압용 일체형 코드의 화재확산 패턴)

  • Shong, Kil-Mok;Kim, Hyang-Kon;Kim, Dong-Ook;Kim, Dong-Woo;Kim, Young-Seok;Choi, Chung-Seog
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.330-334
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    • 2004
  • In this paper, we studied on the fire dispersive patterns and the fire progress at the power cord sets for low voltage appliances in the wall-model. For the experiment, we manufactured a wall-model and applied the external flame at the power cord sets. From the results, short-circuit of the power cord sets was haunted by the external flame it was disconnected with the flashing and the scattering. The fire progress on the polyvinyl chloride insulated flexibel cords is not observed because the ignition energy decreases. In case of rubber insulated flexible cords, however, the fire was progressed continuously. Molten marks were formed at a two electric wire by continuous electric discharge in power source part. A large molten mark was formed in load part. And the columnar structure and voids were observed in molten wire.

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Preliminary Modelling of Plasco Tower Collapse

  • Yarlagadda, Tejeswar;Hajiloo, Hamzeh;Jiang, Liming;Green, Mark;Usmani, Asif
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.397-408
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    • 2018
  • In a recent tragic fire incident, the Plasco Tower collapsed after an intense outburst of fire lasting for three and a half hours and claiming the lives of 16 firefighters and 6 civilians. This paper will present continuing collaborative work between Hong Kong Polytechnic University and Queen's University in Canada to model the progressive collapse of the tower. The fire started at the 10th floor and was observed to have travelled along the floor horizontally and through the staircase and windows vertically. Plasco Tower was steel structure and all the steel sections were fabricated by welding standard European channel or angle profiles and no fire protection was applied. Four internal columns carried the loads transferred by the primary beams, and box columns were constructed along the perimeter of the building as a braced tube for resisting seismic loading. OpenSees fibre-based sections and displacement-based beam-column elements are used to model the frames, while shell elements are used for the reinforced concrete floor slabs. The thermal properties and elevated temperature mechanical properties are as recommended in the Eurocodes. The results in this preliminarily analysis are based on rough estimations of the structure's configuration. The ongoing work looks at modeling the Plasco Tower based on the most accurate findings from reviewing many photographs and collected data.

Modeling fire performance of externally prestressed steel-concrete composite beams

  • Zhou, Huanting;Li, Shaoyuan;Zhang, Chao;Naser, M.Z.
    • Steel and Composite Structures
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    • v.41 no.5
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    • pp.625-636
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    • 2021
  • This paper examines the fire performance of uninsulated and uncoated restrained steel-concrete composite beams supplemented with externally prestressed strands through advanced numerical simulation. In this work, a sequentially coupled thermo-mechanical analysis is carried out using ABAQUS. This analysis utilizes a highly nonlinear three-dimensional finite element (FE) model that is specifically developed and validated using full-sized specimens tested in a companion fire testing program. The developed FE model accounts for nonlinearities arising from geometric features and material properties, as well as complexities resulting from prestressing systems, fire conditions, and mechanical loadings. Four factors are of interest to this work including effect of restraints (axial vs. rotational), degree of stiffness of restraints, the configuration of external prestressed tendons, and magnitude of applied loading. The outcome of this analysis demonstrates how the prestressing force in the external tendons is primarily governed by the magnitude of applied loading and experienced temperature level. Interestingly, these results also show that the stiffness of axial restraints has a minor influence on the failure of restrained and prestressed steel-concrete composite beams. When the axial restraint ratio does not exceed 0.5, the critical deflection of the composite beam is lower than that of the composite beam with a restraint ratio of 1.0.

The Self-regulating Fire Prevention System in Korea: with the Focus on the Role of Insurance System (자율예방체계의 구축 -규제개혁의 차원에서 보험의 역할을 중심으로-)

  • 김태윤
    • Fire Science and Engineering
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    • v.15 no.1
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    • pp.55-65
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    • 2001
  • This paper's purpose is three-folded: modeling the self-regulating fire prevention system, developing a packet of practical fire prevention measures and regulations, and reviewing the applicability of fire insurance system in Korea as a main components of the self-regulating fore prevention system. The so called self-regulating fire prevention system is defined as a grand national fire prevention framework based on and promoted by the vitality and creativeness of the market (or private sector). This drastically contrasts with the existing government-led fire prevention system in Korea. The self-regulating fire prevention system has three grounds: the principle of self-responsibility, the redefinition of the fire service as a public goods, and the principle of self-selection. It seems natural that the self-regulating fire prevention system requires the function of fire insurance institution as a pivoting mechanism providing individual decision makers with a system of incentives, resulting in rational behaviors in the part of each individuals and in the well-balanced fire prevention network in the part of the overall public. In this regard, this pilfer examines the institutions and performance of the fire insurance industry in Korea and reviews the limitation of the industry as an instant replacement mechanism of the current government-led fire prevention system in Korea.

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An Theoretical study on Spalling Mechanism of Concrete (콘크리트 폭렬발생 메카니즘에 관한 이론적 고찰)

  • Kim, Hyung-Jun;Kim, Heung-Youl;Kim, Gyeong-Ok
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.422-427
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    • 2008
  • The major cause of Concrete Spalling at high temperatures can be divided into the Vapor Pressure Rising, caused by the increase in free water temperature within the concrete, and Pore Pressure Rising induced by the vapor moving into dense pores within the concrete. Although the occurrence of spalling within concrete caused by these pressure increases can be assessed experimentally, a close examination into Mechanistic influence against various spalling factors shall be carried out first by using Mathematical Modeling and Theoretical Equations. The Spalling Prospect Process by theoretical mechanism is expedited in order of the following; selection of heating condition (fire strength and flame heating direction), a selection of constituent elements, an analysis of heat transmission, an analysis of moisture movement, distribution of water content, an analysis of pore/vapor pressure, and assessment of spalling occurrence.

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A Study on the Development of a Lanchester-Type Model Incorporating Firing & Observing States in the Direct Fire Engagement (Firing State와 Observing State를 갖는 Lanchester형 전투모형에 관한 연구)

  • Ham Il-Hwan;Choe Sang-Yeong;Song Mun-Ho
    • Journal of the military operations research society of Korea
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    • v.17 no.2
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    • pp.44-53
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    • 1991
  • This paper is aimed to develop a Lanchester type combat model for the direct-fire engagement. This model incorporates number of combatants, inter-firing time, detection time by movement, detection probability by the signature of fire, where the inter-firing time and the detection time are assumed to follow a negative exponential distribution. The approach to modeling is as follows : in the process of an engagement, a combatant takes one of the states('observing' state or 'firing' state), a combatant is initially in the observing state, if the combatant detects a target, he changes his state from 'observing' to 'firing' and will cause attrition to the opposing forces. Thus this transition mechanism is embodied into the differential equation form with each transition rate. A limited examination of the validity has been conducted by comparison with the Monte-Carlo simulation model 'BAGSIM', and with a traditional Deterministic Lanchester model.

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A study on the mine artillery striking method using agent based modeling & simulation (에이전트 기반모의를 통한 갱도포병 타격방안 연구)

  • Kim, Se-Yong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2008.10a
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    • pp.359-363
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    • 2008
  • In recent warfare, importance of counter-fire is increased. New weapon system and counter-fire have critical impact on defeating of the enemy. At an initial battle counter-fire, we need to study about striking plan against the enemy mine artillery. In this paper, we studied, using MANA(agent based model), how much cannon's hit probability and UAV-based target acquisition have influence on striking the mine artillery. We constructed MANA model based on the characteristics of a regional database of Korean peninsula. If we develop detail database of the ROK Army, the proposed MANA model can be used as a war-game model for the regimental level of the Army.

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