• 제목/요약/키워드: Fire spread

검색결과 476건 처리시간 0.021초

비상발전용 UPS 기능을 갖춘 도시철도용 복합형 전력저장시스템 개발 (Development of Hybrid Power Storage System for Urban Railway with UPS Function for Emergency Power Generation)

  • 홍경진
    • 한국인터넷방송통신학회논문지
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    • 제19권6호
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    • pp.191-196
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    • 2019
  • 도시철도 시설물의 경우, 대중교통의 특성상 전력공급이 차단되면 혼란이 발생하므로 통신설비, 방재설비 및 승차장 안전문 등이 안전한 승객의 이동을 위해 전원공급이 유지되어야 한다. 또한, 도시철도 운행노선에는 다수의 전동차가 운행 중이므로 운행 간격과 시설복구 시간을 고려하면 승차장 안전문은 최소 30분 이상, 통신설비 및 방재설비는 1시간 이상의 설비가동이 요구된다. 따라서 도시철도 구간의 역사나 차량화재발생 시 화재로 인한 추가확산을 막기 위해 주요전력이 차단되므로 유도등 및 배연설비의 안정적 동작 유지를 위해 비상 전원공급이 필수적이다. 최근에는 비상시 정전을 방지하는 UPS (uninterruptible power supply, 무정전 전원공급장치) 기능과 가격이 저렴한 야간 시간대에 전기를 저장하였다가 주간 피크시간대에 사용할 수 있도록 하여 전기요금을 절감해주는 ESS 기능을 합친 비상발전용 UPS 기능을 갖춘 복합형 전력저장시스템을 개발하는 추세이다.

콘크리트 누수균열의 유지관리를 위한 누수보수용 주입형 실링재 시공방법 연구 (A Study on the Construction Methods of Sealer of Injection Type for Leakage Maintenance for Water Leakage and Cracks in Concrete)

  • 권시원;오미현;곽규성;오상근
    • 한국건축시공학회지
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    • 제6권1호
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    • pp.87-91
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    • 2006
  • Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

USN환경에서 Agilla를 이용한 개인화된 모바일 에이전트 시스템 구현 (Implementation of Personalized Mobile Agent System using Agilla in Ubiquitous Sensor Network)

  • 김강석;이동철
    • 한국인터넷방송통신학회논문지
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    • 제11권5호
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    • pp.203-210
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    • 2011
  • 현재의 센서네트워크는 고정된 센서노드의 센싱에 의해 수집된 정보를 분석하여 서비스를 제공한다. 이러한 방식은 빌딩 오토메이션, 홈오토메이션, 실시간 도로 기상정보, 헬스케어 환경 등 주요 센싱 대상인 사람의 상태와 위치변화, 그리고 주변 환경의 변화에 능동적으로 대처하기 어렵다. 이러한 다양한 환경에서의 개인별로 적합한 동적 상황을 지원하기 위해서는 사람의 이동과 주변상황의 변화에 따라 능동적으로 차별화된 특정 정보를 제공해주어야 한다. 본 본문에서는 건축물 등에 모바일 에이전트 미들웨어가 탑재된 무선 센서노드들을 설치하여 구축한 센서네트워크 환경을 통해 개인화된 서비스(화재의 발생 위치와 확산경로의 추적 등)를 실시간 제공하는 개인화된 센서 모바일 에이전트 미들웨어를 구현하였다.

Casein 그래프트 카본블랙/폴리우레탄 복합체의 제조와 물성 (Preparation and Properties of Casein graft Carbon black / Polyurethane Composites)

  • 이주엽
    • 한국응용과학기술학회지
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    • 제35권2호
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    • pp.463-471
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    • 2018
  • 본 연구에서는 polypropylene glycol(PPG)을 이용한 수분산 폴리우레탄에 카제인을 그래프트 합성한 다음 카본블랙을 분산하여 발생하는 변화를 분석하였다. 이를 위해 카제인을 그래프트한 수분산 폴리우레탄 (PUD와 CPUD's) 시료를 준비한뒤 카본블랙이 분산된 CPCB's 시료를 준비하였다. 준비된 시료를 이용하여 인장강도를 측정 한 결과 카제인이 높게 함유된 CPUD3가 $3.01kg_f/mm^2$로 인장강도가 증가하였으며, CPCB's에서는 카본 블랙이 증가할수록 인장강도가 $2.54kg_f/mm^2$ 로 낮게 측정되었다. 연신율은 카제인이 적게 함유된 PUD 시료가 278 %로 측정되었으며, CPCB's에서는 CP3CB4가 157%로 측정되었다. 내마모성은 CPUD3 시료가 36.97 mg.loss, CP3CB4가 41.11 mg.loss로 표면 강도가 측정되었다. 내용제성은 PUD's 시료와 CPCB's 시료 양쪽 모두 물성변화가 없음을 확인 할 수 있었다.

개구부 상부 차양설치 및 길이에 따른 외벽 수열온도분포에 관한 연구 (A Study on the External Wall Heating Temperature Distribution According to Opening Upper Shading Installation and Length)

  • 정의인;홍상훈;김봉주
    • 한국건축시공학회지
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    • 제20권4호
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    • pp.339-345
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    • 2020
  • 본 연구는 매년 수만 건 발생되는 화재에서 화재확산에 의한 피해 예방과 대응 마련을 위해 공동주택 및 일반건물의 내부화재를 실물화재실험을 통해 재현하였다. 또한, 개구부 크기와 차양길이 조건을 달리하고 이에 따른 외벽온도 분포를 분석하여 화재확산방지 기초자료를 제공하고자 하였다. 실험결과, 차양을 설치하지 않았을 때 최고온도는 약 380℃ 이상으로 나타났다. 차양을 설치하지 않은 최고온도를 기준으로 차양길이가 150mm 일 때, 동일한 측정점에서 약 90℃가량 낮아졌으며, 300mm에서 약 150℃ 이상, 450mm에서 175℃ 이상 온도가 낮아졌으며, 차양길이 600mm 일 때, 최고온도 차는 약 180℃ 이상 낮아지는 것으로 나타나 개구부 상부의 차양 설치가 외벽의 수직화재 확산에 의한 화염온도를 낮추는데 효과가 있는 것으로 판단된다.

손상통제 함상훈련 시나리오의 효율적 생성에 관한 연구 (A Study on the Efficient Generation of Damage Control Onboard Training Scenarios for Naval Ships)

  • 정재수;이현엽;정정훈;김태진;김숙경
    • 대한조선학회논문집
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    • 제56권5호
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    • pp.457-463
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    • 2019
  • Damage control is a very important preliminary and primary activity to improve the survivability of naval ships by preventing spread of damage, and various types of onboard damage control training are conducted regularly on naval ships. The scenarios for these trainings should be well organized to improve the training efficiency. However, at present, it takes much time and effort to generate the training scenarios and there is a problem that the procedures and contents of the scenarios vary widely depending on the persons who generate, without the established methods and standards. In this paper, an efficient generation method of damage control onboard training scenarios has been established, especially for flood and fire o n naval ships. Also a computer program has been developed based on the established method. The results showed that this method and computer program reduce the time and effort to generate these scenarios, and it is hoped that the method be used as a ROK Navy Standard.

에어커튼형 레인지후드의 슬롯 토출 각도 변화와 배기 효율 (Effect of Slot Discharge-Angle Change on Exhaust Efficiency of Range Hood System with Air Curtain)

  • 성순경
    • 설비공학논문집
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    • 제27권9호
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    • pp.468-474
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    • 2015
  • When oil is used for cooking in detached or apartment houses, large amounts of oil-mist, smoke, and particulate substances are generated and dispersed into the indoor-air environment. These pollutants diffuse into the surroundings and spread their odor while rising fast at a high temperature due to the heat energy from the gas range. Although the exhaust gas is discharged from the exhaust hood, which is installed on the top of a gas range to remove the diffuse pollutants, the exhaust conditions can vary greatly because they depend on the shape of the exhaust hood and the discharge rate. In this paper, the air that is required for the gas-exhaustion process is supplied by an air curtain that surrounds the kitchen hood, and the pollutant-capturing efficiency varies depending on the angle of the discharge grills; the pollutant-capturing efficiency was studied using a numerical-analysis method. The results indicate that the pollutant-capturing efficiency is not significantly changed by a change of the discharge-grill angle at a low air-discharge rate; however, at a high air-discharge rate, the efficiency value increases with an increase of the discharge-grill angle, whereby the best value occurs at 30 degrees and the efficiency decreases above this angle. Below 30 degrees, the effect of the discharge rate on the capturing efficiency is more than that of the discharge-grill angle.

탄소섬유를 이용한 600V 이하 저압 케이블의 전자파 차폐특성 (The Electromagnetic Shield Properties of 600V class Low Voltage Cable Using Carbon Fiber)

  • 김영석;김택희;김종민;송길목;김지연;김원석;곽동순
    • 전기학회논문지
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    • 제66권1호
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    • pp.243-248
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    • 2017
  • This study used general carbon fibers(CF), which can be utilized for a low voltage cable screen, as well as metal-coated carbon fibers(MCF) to make cables and analyzed the properties of electromagnetic effectiveness. Both braid CF and MCF cables with 3,000 strands, 16 spindles, and braid density of 90% or over were adopted. The tape-type MCF specimens were spread into a tape(width: 15mm) using a hot melt to make a cable. The shield effectiveness was measured up to the 1GHz range in accordance with IEC 62153-4-6; braid shielded cables featured a superior shielding effect at 63dB than tape-type shielded cables. That was because the tape-type shielded cable has relatively more gaps and holes between carbon fibers than the braid type, resulting in a more inflow or emission of electromagnetic waves. In the case of braid cables, the characteristics of their electromagnetic waves were enhanced, with higher spindles and higher conductivity of carbon fibers. The shield effectiveness of the MCF shielded cable, however, was lower than that of tin-coated one.

2020 강원영동 강풍 관측에서 지상 바람의 공간 변동성 분석 (Analysis of Spatial Variability of Surface Wind during the Gangwon Yeongdong Wind Experiments (G-WEX) in 2020)

  • 김유정;권태영
    • 대기
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    • 제31권4호
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    • pp.377-394
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    • 2021
  • The recent largest forest fire in the Yeongdong region, Goseung/Okgae fires of 2019 occurred during YangGang wind event. The wind can be locally gusty and extremely dry, particularly in the complex terrain of Yeongdong. These winds can cause and/or rapidly spread wildfires, the threat of which is serious during the dry spring season. This study examines the spatial variability of the surface wind and its coupling with the upper atmospheric wind using the data during the IOP of the Gangwon Yeongdong Wind Experiments (G-WEX) conducted in 2020 and the data during YangGang wind event on 4~5 April 2019. In the case of IOPs, strong wind at the surface with a constant wind direction appears in the mountain area, and weak wind with large variability in wind direction appears from foothill to the coast in the vicinity of Gangneung region. However, in the 2019 event, strong wind at the surface with a constant wind direction appears in the entire region from the mountain to the coast, even with the stronger wind in the coast than in some part of the mountain area. The characteristics of the upper atmospheric wind related with the spatial distribution of surface wind show that during IOPs of G-WEX, a strong downdraft exists near the mountaintop in the level of about 1 to 4 km. However, in the 2019 event a strong downdraft is reinforced, when its location moves toward the coast and descends close to the ground. These downdrafts are generated by the breaking of mountain waves.

Traditional Unani Medicine in Flu-like Epidemics and COVID-19 during Pregnancy: A Literary Research

  • Sultana, Arshiya;Khanam, Marhaba;Rahman, Khaleequr;Sumbul, Sumbul
    • 셀메드
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    • 제11권4호
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    • pp.20.1-20.23
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    • 2021
  • Background: The pandemic COVID-19 caused by a novel coronavirus SARS-COV-2 has spread like a forest fire. This disease may have serious consequences for pregnant women. Presently, no specific drugs or vaccines exist to battle this disease and researches are underway. Unani medicine has a unique role in prevention and management during epidemics. Here, we reviewed the overview of COVID-19 infection and pregnancy, concept and practices in Unani medicine for flu-like epidemics in general and pregnancy, and safety of Unani drugs for the prevention and treatment of mild symptomatic cases of COVID-19 during pregnancy. Methodology: Unani classical texts and pharmacopoeia were meticulously explored for concepts and practices for flu-like epidemic diseases. Further, we browsed scientific databases such as PubMed, Scopus and others for an overview, epidemics and Unani medicine, effectiveness and safety of Unani drugs in COVID-19 and pregnancy. Results: Unani medicine includes prevention and management of flu-like epidemic include quarantine and isolation, aromatic herbal drugs fumigation and spraying for environmental disinfection, ilaj bid tadbir for health promotion and use of health-protecting drugs and symptom-specific drugs in general and related to pregnancy. Lahsun, asalussus, behidana, banafsha, zanjabeel, unnab, etc are in use since antiquity for the prevention and treatment of asymptomatic and mildly symptomatic pregnant women during infectious and epidemic diseases. Conclusion: Currently, the aforementioned plants are proven for antiviral, antioxidant, immunomodulatory and anti-inflammatory activities, probably useful in the COVID-19 pandemic. Additionally, scientific studies have provided new insight into the mechanism underlying the therapeutic effect of Unani medicines that are safe in pregnancy.