• 제목/요약/키워드: fire cases

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퍼지추론을 이용한 지식기반 전기화재 원인진단시스템 (A Knowledge-based Electrical Fire Cause Diagnosis System using Fuzzy Reasoning)

  • 이종호;김두현
    • 한국안전학회지
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    • 제21권3호
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    • pp.16-21
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    • 2006
  • This paper presents a knowledge-based electrical fire cause diagnosis system using the fuzzy reasoning. The cause diagnosis of electrical fires may be approached either by studying electric facilities or by investigating cause using precision instruments at the fire site. However, cause diagnosis methods for electrical fires haven't been systematized yet. The system focused on database(DB) construction and cause diagnosis can diagnose the causes of electrical fires easily and efficiently. The cause diagnosis system for the electrical fire was implemented with entity-relational DB systems using Access 2000, one of DB development tools. Visual Basic is used as a DB building tool. The inference to confirm fire causes is conducted on the knowledge-based by combined approach of a case-based and a rule-based reasoning. A case-based cause diagnosis is designed to match the newly occurred fire case with the past fire cases stored in a DB by a kind of pattern recognition. The rule-based cause diagnosis includes intelligent objects having fuzzy attributes and rules, and is used for handling knowledge about cause reasoning. A rule-based using a fuzzy reasoning has been adopted. To infer the results from fire signs, a fuzzy operation of Yager sum was adopted. The reasoning is conducted on the rule-based reasoning that a rule-based DB system built with many rules derived from the existing diagnosis methods and the expertise in fire investigation. The cause diagnosis system proposes the causes obtained from the diagnosis process and showed possibility of electrical fire causes.

중저압 물분무를 이용한 객차내 화재진압에 관한 실험 및 수치해석적 연구 (An Experimental and Numerical Study on Fire Suppression Using a Mid-low Pressure Water Mist in a Carriage Fire)

  • 노재성;양승신;김동현;정우성;장용준;유홍선
    • 한국철도학회논문집
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    • 제9권3호
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    • pp.291-297
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    • 2006
  • The present study investigated the effect of fire suppression using a mid-low pressure water mist in a carriage fire. The fire extinguishing time and temperature distributions below ceiling in the enclosed compartment of $2.9m{\times}2.8m{\times}5.0m$ were measured by stopwatch and k-type thermocouples for various fire positions. The numerical simulations were extensively performed using. Fire Dynamics Simulator(FDS, Ver. 4.0) code and the predictions were compared with experimental data. The prediction results showed good agreement with the measured maximum temperature in the all cases. Whereas the predicted temperature was about $40^{\circ}C$ higher than the measured one after operating of water mist. The predicted fire extinguishing times were compared with those of measured data. Fires are extinguished within 200 seconds at the experiment in Case 2 and Case 3. But in Case 1 fire was not extinguished in the numerical simulation. The reason of the discrepancy between predicted and measured data was that a simple suppression algorithm has been implemented in FDS. Also, various databases of fire properties for combustible materials and more elaborate model considering the water mist were required fur better predictions of the cooling and suffocation effect.

1회용 가스라이터로 인한 화재 원인과 예방대책의 조사·분석 (Research and Analysis of the Causes and Preventive Measures of Fires Caused by a Disposable Gas Lighter)

  • 이의평
    • 한국화재소방학회논문지
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    • 제31권2호
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    • pp.74-81
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    • 2017
  • 이 논문에서는 1회용 가스라이터의 규제실태, 화재발생 실태, 화재 및 사고의 발생원인, 예방대책을 조사 분석하였다. 1회용 가스라이터에 어린이 보호기능이 의무화된 이후에는 미국과 일본 등과 마찬가지로 전체화재 중 불장난으로 인한 화재의 비율이 감소하고 있다. 1회용 가스라이터로 인한 화재는 방화와 불장난을 제외하면 잔화, 의도하지 않은 점화, 큰 화염 발생, 고온장소 방치로 인한 파열 또는 폭발 등에 의해 발생하고 있다. 예방대책은 어린이 불장난 도구로 이용될 수 없게 조치, 잔화로 인한 화재사례 홍보, 차량 대시보드 위 또는 고온장소 방치의 위험성 홍보, 차량 의자 레일 멈춤 부분의 보호용 합성수지 커버의 개선, 서랍 등에 보관 시 주의사항 홍보, 폐기방법 홍보 등을 제안한다.

수장고에 설치된 소방시설의 실태 및 개선방안에 관한 연구 (Study of the Real Condition and Improvement Plans of a Fire Protection System Installed at Museum Storage)

  • 박종아;주승호;강은수;이대건
    • 한국화재소방학회논문지
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    • 제32권3호
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    • pp.60-66
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    • 2018
  • 근래 박물관에 대한 변화 중 주목할 부분으로 학예사 및 관리자 등 전문가의 고유영역이었던 수장고가 점차 관람객에게 공개되는 형태로 바뀌고 있어 관람객의 부주의 등에 따른 화재 위험도는 증가할 것이며, 그에 따른 소방시설 또한 변화하는 수장고에 적응할 수 있는 알맞은 대책 마련이 필요하다고 사료된다. 이에 본 논문에서는 문화체육관광부의 지원을 받아 국내 40개소 공립박물관의 답사를 통해 수장고에 적용된 소방시설의 현황을 분석하였으며, 수장고에 적응성이 떨어지는 소방시설 혹은 관리가 미흡하거나 우수한 소방시설의 사례들을 도출하여 그에 따른 소방시설의 설치방향을 제시하였고, 수장고에 개선하여 적용할 수 있도록 방향을 제시하였다.

The bearing capacity of monolithic composite beams with laminated slab throughout fire process

  • Lyu, Junli;Zhou, Shengnan;Chen, Qichao;Wang, Yong
    • Steel and Composite Structures
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    • 제38권1호
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    • pp.87-102
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    • 2021
  • To investigate the failure form, bending stiffness, and residual bearing capacity of monolithic composite beams with laminated slab throughout the fire process, fire tests of four monolithic composite beams with laminated slab were performed under constant load and temperature increase. Different factors such as post-pouring layer thickness, lap length of the prefabricated bottom slab, and stud spacing were considered in the fire test. The test results demonstrate that, under the same fire time and external load, the post-pouring layer thickness and stud spacing are important parameters that affect the fire resistance of monolithic composite beams with laminated slab. Similarly, the post-pouring layer thickness and stud spacing are the predominant factors affecting the bending stiffness of monolithic composite beams with laminated slab after fire exposure. The failure forms of monolithic composite beams with laminated slab after the fire are approximately the same as those at room temperature. In both cases, the beams underwent bending failure. However, after exposure to the high-temperature fire, cracks appeared earlier in the monolithic composite beams with laminated slab, and both the residual bearing capacity and bending stiffness were reduced by varying degrees. In this test, the bending bearing capacity and ductility of monolithic composite beams with laminated slab after fire exposure were reduced by 23.3% and 55.4%, respectively, compared with those tested at room temperature. Calculation methods for the residual bearing capacity and bending stiffness of monolithic composite beams with laminated slab in and after the fire are proposed, which demonstrated good accuracy.

耳鳴에 관한 임상적 연구 (A Clinical Study of Tinnitus)

  • 최인화
    • 한방안이비인후피부과학회지
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    • 제14권2호
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    • pp.134-145
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    • 2001
  • Introduction: Noises in the ear, whether real or imagined, are called tinnitus. Subjective causes of tinnitus(which is heard only by the patient) are extremely common and the majority of them are treated conservatively. For certain individuals their tinnitus is a major handicap; for others a trivial concern. The most common from of subjective tinnitus is a rushing, hissing or buzzing noise; it is frequently associated with sensorineural heanng loss. The patient may be unaware of the hearing loss, especially if it is a high frequency deficit of moderate severity. The character of the tinnitus may give a clue to the etiology. But the patient often has difficulty in explaining his/her tinnitus in absolute terms, as they have no other tinnitus with which to compare it but their own Tinnitus, like pain, is a subjective state and trying to objectively assess the severity is problematic. Audiological techniques to match subjective loudness to machine-produced noise may offer some help, in that sound intensity matches can bear little correspondence to subjective complaint. In spite of many studies, most patients presently seen complaining of tinnitus are told by their doctors that there is no treatment and that they will have to learn to live with this symptom. Objectives: To perform a clinical analysis of tinnitus and estimate the efficacy of Oriental Medical treatment according to the Byeonjeung(辨證). Subject: We studied 34 patients with complaints of tinnitus who had visited Pundang Cha Oriental Medicine Hospital Department of Otorhinolaryngology from March 1998 to February 2000. All of them had been treated 2 or 3 times a week with acupuncture treatment and had taken herbs according to the Byeonjeung(辨證) method. It was therefore possible for me to know whether their symptoms improved or not. Parameters Observed and Method: We treated them with acupuncture & herb-medication. Sometimes we gave them moxibustion or negative therapy with bloodletting at the acupuncture points(耳門, 聽宮, 聽會). Parameters Observed 1) Distribution of age & sex 2) Chief complaints 3) The sites of tinnitus 4) The quality of tinnitu 5) The duration of disease 6) The problem induced tinnitus 7) Factors increasing disease severity 8) The classification of the Byeonjeung(辨證) 9) The efficacy of treatments Results: 1. Age and sex distribution: The most common occurrence was found in males in their twenties: 6 males($17.7\%$), and in females in their thirties and over sixty: 8 females($23.5\%$). Total patient numbers for men and women were 20 men($58.8\%$), 14 women ($41.2\%$). 2. The most frequent major complaints were hearing disturbances related to tinnitus; and dizziness with tinnitus; each comprising 10 cases($29.4\%$). There were also 7 patients($20.6\%$) with only tinnitus. 3. Tinnitus sites: 13($38.2\%$) said that they felt tinnitus in both ears, equally. In the right ear, 9($26.5\%$), in the left, 6($17.7\%$). 4. The most frequent descriptive symptoms of tinnitus were: humming, hissing, buzzing etc. 5. The duration of disease. 14cases($41.2\%$) had a duration of less than 1 year. 6. 15cases($44.1\%$) complained that it was hard to watch TV or make a phone call because of tinnitus. 10 cases($29.4\%$) complained about depression. 7. Factors increasing severity of tinnitus: ⅰ) fatigue: 18cases($52.9\%$) ⅱ) stress/ tension: 10 cases($29.4\%$) ⅲ) alcohol and tobacco: 5cases($l4.7\%$) 8. Classification through Byeonjeung : ⅰ) 19 cases($55.9\%$) were classified as showing Deficiency syndrome. ⅱ) 15 cases($44.l\%$) were classified as showing Excess syndrome. The deficiency of Qi was 7($20.6\%$), deficiency of Xue, 8($23.5\%$) and insufficiency of the Kidney Yin & Yang, 4($11.8\%$). The flare of Liver fire was 8($23.5\%$) and phlegm-fire, 7($20.6\%$), 9. The efficacy of treatments showed: an improvement in 17cases($50.0\%$); no real improvement or changes in 13 cases($38.2\%$); and some worsening in 4 cases($11.8\%$). In the group with deficiency in Qi, 4($57.1\%$) improved, 1($14.3\%$) showed no change and 2($28.6\%$) were aggravated. In the cases of deficiency in Xue, 6($75.0\%$) improved, 2($25.0\%$) showed no change. In the cases of insufficiency of Kidney Yin & Yang, 3($75.0\%$) showed no change and 1($25.0\%$) were aggravated. In the group of flare of Liver fire, 4($50.0\%$) improved, 3($37.5\%$) no change and 1($12.5\%$) were aggravated. In the cases of phlegm-fire, 3($42.9\%$) improved, 4($57.1\%$) showed no change. Conclusion: We would recommend that any further studies of tinnitus utilize trial treatments of longer than 2 months duration, as any positive effects observed in our study showed that improvement occurred fairly slowly. And we suggest that this study could be utilized as a reference for clinical Oriental Medical treatment of tinnitus. If we try to apply music or sound therapy treatment properly combined with ours, we expect it to provide psycological stability in addition to inducing masking effects, even though it may not directly decrease or completely remove tinnitus.

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A Numerical Study on the Effects of the Smoke Exhaustion on Safe Evacuation in Emergency Situations during Fires on Ships

  • Kim, Won-Ouk
    • 한국항해항만학회지
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    • 제37권1호
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    • pp.85-89
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    • 2013
  • Sometimes, an evacuation should be executed from a ship for many reasons. This study considers on emergency evacuation on fire in a ship, one of the many reasons for evacuation. Due to the characteristic of fire, the most loss of life is known to be caused by suffocation resulted by smoke. To reduce the suffocation by smoke, the time available for evacuation should be improved for the higher survival rate of crews. In this study, crews' survival times and Evacuation time are analyzed quantitatively in during fire in the same sealed space in two different cases of the natural ventilation and the forced ventilation.

양방향 USN기반 원격 화재 감시 시스템 구현 (Implementation of A Remote Fire Monitoring System Based on Bidirectional USN)

  • 정태윤;정한수;박래정;이형봉;문정호
    • 대한임베디드공학회논문지
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    • 제2권2호
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    • pp.107-115
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    • 2007
  • In general, wireless sensor networks composed of many nodes which are located in ad. hoc environment and send the gathered data to sink node support only one way traffic. In those cases, it is not possible to send commands to nodes to react for exceptional events because the networks can not deliver downward data and the nodes run in pre-assigned fixed schedule. This paper expands the WSLP to bidirectional WSLP and implements a fire monitoring system on it, and shows the feasibility of bidirectional USN by demonstrating the usability of the process of reaction to a fire in the implemented fire monitoring system.

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Numerical Simulations of the Supersonic Jet Impingement in a Confined Plenum of Vertical Launching System

  • Lee Kwang-Seop;Lee Jin-Gyu;Hong Seung-Kyu;Ahan Chang-Soo
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2006년도 PARALLEL CFD 2006
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    • pp.301-305
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    • 2006
  • The Vertical Launching System design is especially complicated by complex flow structure in a plenum with the severe thermal state and high pressure load form the hot exhaust plume. The flow structures are numerically simulated by using the commercial code, CFD-FASTRAN with the axi-symmetrical Navier-Stokes equations. Two different cases are considered; that is, the stationary fire and the moving fire.

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