• Title/Summary/Keyword: 地气

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Antioxidant Activities of Extracts from Artemisia capillaris $T_{HUNB}$. and Artemisia iwayomogi $K_{ITAM}$. used as Injin (인진(茵蔯)으로 쓰이는 사철쑥과 더위지기 추출물의 항산화 활성)

  • Seo, Kyoung-Sun;Yun, Kyeong-Won
    • Korean Journal of Plant Resources
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    • v.21 no.4
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    • pp.292-298
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    • 2008
  • The antioxidant activities of Artemisia capillaris and Artemisia iwayomogi used as Injin (Korean herbal name) were investigated. The DPPH radical scavenging activity of the ethylacetate fractions obtained from the Artemisia capillaris and Artemisia iwayomogi was higher than other fractions. No DPPH radical scavenging activity was observed in hexane frcations. The nitrite scavenging activity was the highest at pH 1.2, and the peroxide value for linoleic acid was increased during the incubation.

A Study on the Problem of Tester for the Field Inspection of the Photoelectric Smoke Detector (광전식연기감지기 현장점검기기의 문제점에 관한 연구)

  • Kim, Shi-Kuk;Yuk, Hyun-Dai;Yang, Seung-Hyun;Jee, Seung-Wook;Lee, Chun-Ha
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.137-144
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    • 2009
  • This paper was studied on the problem of field inspection tester of the photoelectric type smoke detector. The experiment objects were chosen 3 type's testers such as A type (incense), B type (dimethylpolysiloxane), C type (mixtures of hydrocarbon) which were used for performance checking of the photoelectric type smoke detector for the fire protection. The experimental methods were used reliability verification experiment, performance verification experiment and performance change of fire detector by smoke component. It was confirmed through the experiment that the testers had problems of smoke concentration condition and wind velocity condition and smoke component. Consequently, this paper verified that the field inspection testers of the photoelectric type smoke detector had problems in the inspection of fire protection.

A study on the Response Timing for an Installation Location of Gas Sensors using Computational Analysis (전산해석을 이용한 가스센서 설치위치에 따른 응답시간에 관한 연구)

  • Kim, Hyun-Il;Kim, Young-Doo;Park, Gyou-Tae;Han, Sang-In;Kwon, Jeong-Rock
    • Proceedings of the KIEE Conference
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    • 2008.10b
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    • pp.382-383
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    • 2008
  • 현재 가정이나 산업용으로 사용하는 가스 화기나 보일러 등에서 가스 누출에 의한 화재사고나 폭발사고가 빈번하게 발생하고 있다. 가스 누출에 의한 사고는 오랜 시간 가스 누출 후 점화원에 의한 폭발이나 화재사고가 대다수를 차지한다. 일반적으로 천연가스를 사용하는 경우 상단부에 가스누출검지기를 설치하고 있다. 하지만 이러한 설치 위치는 대략적인 가스의 특성을 고려한 것이다. 본 연구에서는 가스 누출이 발생할 수 있는 누출위치를 가정의 가스레인지 화구와 밸브 연결부로 선정하고, 전산유체역학(CFD)을 이용하여 가스누출검지기의 시간에 따른 응답특성을 파악하여, 빠른 가스 검지를 위해 가스누출검지기 설치 위치를 최적화하였다. 본 연구의 결과를 기초로 가정이나 건물의 가스누출검지기출 설치할 경우, 가스가 누출되었을 때 신속한 검지를 통하여 위험을 알림으로서 가스폭발이나 사고를 미연에 방지할 수 있을 것이다.

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A Study on the Response Characteristics of the Residential Smoke Detector Depending on Controlled Fire Tests (화재실험을 통한 주택용 연기감지기 응답특성에 관한 연구)

  • SaKong, Seong-Ho;Kim, Shi-Kuk;Lee, Chun-Ha;Jung, Jong-Jin
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.98-103
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    • 2009
  • In this paper, in order to analyze the response characteristics of the smoke detectors which is suitable with the residential fire detector, the paper fire and flammable liquid fire experiment came to be accomplished according to UL Standard for safety for smoke detector for fire alarm signaling systems, UL 268. Also Photoelectric smoke detector, the Analog smoke detector and the single station alarm device came to be used with the specimen and the response characteristics of the smoke detectors which follows in these two types(paper, flammable liquid) test fire came to be analyzed. As a result, according to test fire there was some difference to response characteristics of the smoke detectors.

A Study on the Test and Installation Standards of the Video Fire Detector (영상화재감지기 시험과 설치기준에 관한 연구)

  • Lee, Jeong-Hyun;Baek, Dong-Hyun
    • Fire Science and Engineering
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    • v.30 no.4
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    • pp.1-5
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    • 2016
  • This research performed tests of Video Fire Detector and criteria of installation to make suggestions regarding the criteria that must be reflected in NFSC 203 by comparing the standards of FM Approvals, UL, ISO7240 and NFPA 72. FM Standard related to Video Fire Detector test has been classified as Smoke, Flame type, but the UL Standard has classified only as a Smoke type. This research examined 6 cases of fire phenomenon detection case in ISO 7240 and 3 cases in NFPA 72, respectively. There are 15 items required for the installation standard of a Video Fire Detector and each field standard is presented as a per installation method. To apply a Video Fire Detector, the pertinent items (the definition of term, detector's classification, structure and function among its test item) must be inserted. In addition, 7 items of the fire test, i.e., the sensitivity adjustment, prevent false alarm, ambient temperature test, the effective sensitivity and detection distance and viewing angle, aging test, flood test, must be applied to the actual test. For installation in the field, the operation environment and levels of illumination, and NFSC 203 must be set, and standards relevant to the sound system, indicators' installation distance, etc. need to be inserted.