• 국제초고층학회논문집
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• 제10권4호
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• pp.265-283
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• 2021

To ensure that fire induced collapse of a building is prevented it is important to understand the sequence of events that can lead to this event. In this paper, the initiation of collapse mechanisms of generic a multi-storey steel frame subjected to vertical and horizontal travelling fires are analysed computationally by tracking the formation of plastic hinges in the frame and generation of fire induced loads. Both uniform and travelling fires are considered. In total 58 different cases are analysed using finite element software LS-DYNA. For the frame examined with a simple and generic structural arrangement and higher applied fire protection to the columns, the results indicate that collapse mechanisms for singe floor and multiple floor fires can be each split into two main groups. For single floor fires (taking place in the upper floors of the frame (Group S1)), collapse is initiated by the pull-in of external columns when heated beams in end bays go into catenary action. For single floor fires occurring on the lower floors(Group S2), failure is initiated (i.e. ultimate strain of the material is exceeded) after the local beam collapse. Failure in both groups for single floor fires is governed by the generation of high loads due to restrained thermal expansion and the loss of material strength. For multiple floor fires with a low number of fire floors (1 to 3) - Group M1, failure is dominated by the loss of material strength and collapse is mainly initiated by the pull-in of external columns. For the cases with a larger number of fire floors (5 to 10) - Group M2, failure is dominated by thermal expansion and collapse is mainly initiated by swaying of the frame to the side of fire origin. The results show that for the investigated frame initiation of collapse mechanisms are affected by the fire type, the number of fire floors, and the location of the fire floor. The findings of this study could be of use to designers of buildings when developing fire protection strategies for steel framed buildings where the potential for a multifloor fire exists.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.625-628
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• 2008

The behavioral response of the individuals intimately involved with the initiation of the fire or those who aware of the initial fire cue, often appeared to be a determinant to the outcome of the fire incident, the nonadaptive flight or panic type behavioral response appears to be an infrequent, unusual or unique participant behavioral response in most fire incidents. Therefore, this study focused on the investigation of the individual behavioral responses depend on the distinction of sex and age.

• 한국화재소방학회논문지
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• 제12권2호
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• pp.61-68
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• 1998

가축사료 분진의 열적 안정성 실험결과 본 연구에서 사용한 시료 입도의 경우 발열개시온도 및 발열 량에는 별 차이가 없었으나, 숭온속도가 충가함에 따라 발열개시온도가 낮아지고, 입도가 미세해질수 록 분해열이 증가함을 알 수 있었다. 한편, 분위기 기체룰 조연성 기체인 Oz로 사용할 경우 불활성 기 체인 Nz를 사용하는 경우보다 발열개시온도는 현저히 낮아지며, 반면에 발열량도 20배 이상 중가하였 다. 또한 본 연구에서 사용한 시료중 비교적 미세업자가 대기중에 부유하기 쉽고, 외부에서 점화에너지 가 주어질 경우 공기중의 산소와 쉽게 순간적으로 반용하여 폭발하는 것올 볼 수 있다. 본 연구에서의 시료입도중 80/100 mesh의 경우 평균 최대폭발압력은 6.88 Kgf / cm2 로 구해졌다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제31회 추계학술대회논문집
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• pp.273-276
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• 2008

오링을 사용하지 않고 기밀을 유지할 수 있는 점화안전장치용 격벽 착화모듈을 설계하였다. 격벽 착화모듈은 도우너 화약에 의해 발생한 충격파가 격벽을 통해 억셉터 화약에 전달되었을 때 동작한다. 격벽 착화모듈의 구조적 안전성을 구조해석을 통해 확인하였고 점화 성능은 10cc 밀폐용기 시험을 통하여 검증하였다. 동작시험 결과를 토대로 통계적 처리방법인 Probit Method를 이용하여 신뢰도 분석을 하였다. 신뢰도 분석 결과를 통하여 격벽 착화모듈의 중요한 설계변수인 격벽두께를 결정하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.206-212
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• 2009

Chemical behaviors of each surface material for interior facilities affect to fire initiation and growth in general fire situation. These chemical behaviors were characterized by thermal properties (Heat release rate, Pyrolysis rate, specific heat, etc) which could be derived from experimental test. Especially, Heat release rate which indicates aspect of fire size is one of the most important property to asses fire hazard and protection needs. The cone calorimeter test (ISO 5660) has recently assumed to a dominant role in bench scale fire testing to obtain the Heat release rate of materials. This value could be calculated by the 'Oxygen Consumption Method' under various producing irradiances to each surface of materials. In this study, Process of the cone calorimeter test was simulated by Pyrolysis model of FDS (Fire Dynamics Simulator by NIST) base on the ISO 5660 international standard. Then, we could estimate the simulation method of FDS in case of single materials through the comparative study with test results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.960-969
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• 2006

In this study, a series of fire tests was carried out to evaluate fire-induced damage to structural members in tunnels. From the tests, the loss amount of concrete materials by the RWS fire scenario was slightly bigger than by the RABT fire scenario. Especially under the RWS fire scenario where the maximum temperature is over 1,200, the loss of concrete materials was mainly induced by melting. Generally, the loss of materials in reinforced concrete was slightly smaller than that in unreinforced concrete. Depending upon an applied fire scenario, fire-induced damage to shotcrete was quite different. From the real-time investigation of a specimen surface by a digital camcorder, it was proved that the material loss under the RABT fire scenario was mainly induced by spalling. However, it was also revealed that although fire-induced damage in the initial heating stage under the RWS was so close to that under the RABT, the material loss under the RWS at the later stage after 50 minutes elapsed since fire initiation was induced not by spalling but by melting.

• 한국전자통신학회논문지
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• 제13권6호
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• pp.1287-1292
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• 2018

화재가 발생하면 효율적인 화재 진압을 위하여 소방관은 화점 정보를 포함한 화재 관련 정보가 필요하다. 그러나 기존의 화재 감지 시스템은 현장의 소방관에게 화재 정보를 시각적으로 전달하지 못하는 문제가 있다. 이 논문에서는 이를 해결하기 위하여 클라우드 서버를 이용한 화점 표출 시스템을 제안한다. 제안한 시스템에서 각 건물에 설치된 센서들은 온도 및 가스 정보를 수집하고 무선 네트워크를 통하여 클라우드 데이터베이스에 저장한다. 현장의 소방관을 위하여 클라우드 데이터베이스에 저장된 특정 건물의 도면과 함께 화점 데이터의 상세와 시간에 따른 이력을 스마트 기기에 표출한다.

• 한국화재소방학회논문지
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• 제23권4호
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• pp.104-111
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• 2009

국내 저층 공동주택 화재시의 화재 전파 경로와 상층으로의 화재 전파를 살펴보기 위하여 4층 공동 주택을 대상으로 실물화재 실험을 수행하였다. 화재는 3층 주택에서 발화하는 것으로 하였고, 초기 화원은 주방에서 과열된 식용유에 발화되어 발생하는 것으로 하였다. 주택 내부 가연물은 일반 가정의 필수 가연물을 모두 포함하였다. 내부 화재 성상을 확인하기 위하여 가시화, 주요부의 온도측정, 산소농도 측정을 수행하였다. 실험 결과 초기 화원의 발화 시간, 화재 층 내부 각 구획으로의 전파시간, 전역화재 발생시간을 파악하였으며, 상층으로의 연소확대 경로를 파악하였다.

• Geosystem Engineering
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• 제21권5호
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• pp.282-290
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• 2018

The onset of extreme fire behaviour in a mine drift with longitudinal ventilation was analysed. A fire in a mine drift with continuous fuel load, involving several separate fires may lead to flames tilted horizontally and filling up the entire cross section. This will lead to earlier ignition, higher fire growth rate, higher fire spread rate and a severe fire behaviour. The focus has been on what changes take place at the onset and signs of the impending phenomenon. It was found that the fire gas temperature at the ceiling level provided a poor indicator. At the downstream far-field region of the fire, the sudden temperature increase at the lowest levels of the cross section and the sudden increase in flow velocities would provide signs of extreme fire behaviour. The corresponding full-scale heat release rates of the experiments at the onset of extreme fire behaviour were found to be very high for mining applications but not necessarily for tunnel fires. The heat release rate threshold for a mine drift with smaller cross-sectional dimensions would decrease considerably, increasing the likelihood of occurrence. The distance between the fuel items will play an important role during the initiation of horizontal flames.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 1994년도 제3회 학술강연회논문집
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• pp.21-26
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• 1994

Conventional electroexplosive devices (EED) commonly use a very small metal bridgewire to ignite explosive materials i.e. pyrotechnics, primary and secondary explosives. The use of semiconductor devices to replace “hot-wire” resistance heating elements in automotive safety systems pyrotechnic devices has been under development for several years. In a typical 1 amp/1 watt electroexplosive devices, ignition takes place a few milliseconds after a current pulse of at least 25 mJ is applied to the bridgewire. In contrast, as for a SCB devices, ignition takes place in a few tens of microseconds and only require approximately one-tenth the input energy of a conventional electroexplosive devices. Typically, when SCB device is driven by a short (20 $\mu\textrm{s}$), low energy pulse (less than 5 mJ), the SCB produces a hot plasma that ignites explosive materials. The advantages and disadvantages of this technology are strongly dependent upon the particular technology selected. To date, three distinct technologies have evolved, each of which utilizes a hot, silicon plasma as the pyrotechnic initiation element. These technologies are 1.) Heavily doped silicon as the resistive heating initiation mechanism, 2.) Tungsten enhanced silicon which utilizes a chemically vapor deposited layer of tungsten as the initiation element, and 3.) a junction diode, fabricated with standard CMOS processes, which creates the initial thermal environment by avalanche breakdown of the diode. This paper describes the three technologies, discusses the advantages and disadvantages of each as they apply to electroexplosive devises, and recommends a methodology for selection of the best device for a particular system environment. The important parameters in this analysis are: All-Fire energy, All-Fire voltage, response time, ease of integration with other semiconductor devices, cost (overall system cost), and reliability. The potential for significant cost savings by integrating several safety functions into the initiator makes this technology worthy of attention by the safety system designer.