• 제목/요약/키워드: protection ability

검색결과 518건 처리시간 0.026초

Water Mist Fire Suppression for Raised Subfloor Spaces

  • Kim, Woon-Hyung;Kim, James A. Milke
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.617-624
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    • 1997
  • Over 100 experiments have been conducted at the University of Maryland to evaluate the performance of a water mist fire suppression system for protection of an interstitial space below a raised subfloor. Experiments are conducted as part of an ongoing research effort to compare the fire suppression capabilities of various water mist system designs in a raised subfloor space. Water mist system design parameters considered in the investigation include means of actuation, concentration of water mist required for extinguishment of fires, and delivery mechanisms of water mist within close proximity to the fire. Delivery of the required concentration of water mist within close proximity to the fire is a principal factor governing the adequacy of water mist systems. Two sets of experiments have been conducted to document the performance of water mist system designs. One set is involved in documenting the concentration of water mist as a function of position within the space. The second set of experiments is concerned with the ability of water mist system designs to control fires in the space. One result of the research is the assessment of the ability of a water mist system to control fires at particular locations as a function of water mist density at that location.

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Carbohydrase inhibition and anti-cancerous and free radical scavenging properties along with DNA and protein protection ability of methanolic root extracts of Rumex crispus

  • Shiwani, Supriya;Singh, Naresh Kumar;Wang, Myeong Hyeon
    • Nutrition Research and Practice
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    • 제6권5호
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    • pp.389-395
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    • 2012
  • The study elucidated carbohydrase inhibition, anti-cancerous, free radical scavenging properties and also investigated the DNA and protein protection abilities of methanolic root extract of Rumex crispus (RERC). For this purpose, pulverized roots of Rumex crispus was extracted in methanol (80% and absolute conc.) for 3 hrs for $60^{\circ}C$ and filtered and evaporated with vacuum rotary evaporator. RERC showed high phenolic content ($211{\mu}g$/GAE equivalent) and strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ($IC_{50}$ = 42.86 (absolute methanol) and $36.91{\mu}g/mL$ (80% methanolic extract)) and reduced power ability. Furthermore, RERC exhibited significant protective ability in $H_2O_2/Fe^{3+}$/ascorbic acid-induced protein or DNA damage and percentage inhibition of the HT-29 cell growth rate following 80% methanolic RERC exposure at $400{\mu}g/mL$ was observed to be highest ($10.2%{\pm}1.03$). Moreover, methanolic RERC inhibited ${\alpha}$-glucosidase and amylase effectively and significantly (P < 0.05). Conclusively, RERC could be considered as potent carbohydrase inhibitor, anti-cancerous and anti-oxidant.

국방 EMP 방호능력의 효율적 개선을 위한 방안 연구 (A Study for the Efficient Improvement Measures of Military EMP Protection Ability)

  • 정승훈;안재춘;황영규;정현주;신용태
    • 예술인문사회 융합 멀티미디어 논문지
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    • 제7권1호
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    • pp.219-227
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    • 2017
  • 현재 군 지휘정보체계는 반도체칩이 장착된 전자기기의 활용도가 높으며, 최신 정보통신기술 발전에 따라 그 비중은 더욱 증가할 것으로 예상된다. 전기를 사용하는 전자기기의 경우 고출력 전기신호에 대한 일정한 내성을 보유하고 있다. 이러한 전자기기 내성을 기준화 한 것이 EMC 규격이다. 한편 원자력 연구원에서는 서울 상공 100km지점에서 10kt급의 핵폭발이 발생할 경우 반경 170km 지역까지 고출력전자기파가 발생하여 해당지역 대부분 전자장비에 피해가 예상된다는 시뮬레이션 결과를 발표한 바 있다. 이러한 경우 발생하는 영향을 방호하기 위한 기준은 EMP 방호 규격으로 정의된다. 대부분의 상용 전자기기의 경우 EMC 기준은 충족하지만 EMP 기준을 충족하는지의 여부를 확인할 수가 없다. EMP 방호기준 충족여부를 확인하기 위한 장비와 절차가 쉽지 않고 비용적인 측면이 있기 때문이다. 보통 부득이한 경우를 제외하고는 EMP 방호기준 충족여부에 대해서는 검증하지 않는 실정이다. 이점을 고려하여 본 연구에서는 EMC-EMP 상관관계 분석을 통하여 일반 전자기기의 EMP 방호능력에 대해서 확인하고 이를 바탕으로 EMP 방호능력 향상방안을 확인하였다.

실리콘 혼합 차폐체의 개발과 성능비교 (Development and Performance Comparison of Silicon Mixed Shielding Material)

  • 정회원;민정환
    • 대한방사선기술학회지:방사선기술과학
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    • 제46권3호
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    • pp.187-195
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    • 2023
  • A shield was made by mixing materials such as bismuth(Bi) and barium(Ba) with silicon to evaluate its shielding ability. Bismuth was made into a shield by mixing a bismuth oxide(Bi2O3) colloidal solution and a silicon base and applied to a fibrous fabric, and barium was made by mixing lead oxide(PbO) and barium sulfate(BaSO4) with a silicon curing agent and solidifying it to make a shield. The test was conducted according to the lead equivalent test method for X-ray protective products of the Korean Industrial Standard. The experiment was conducted by increasing the shielding body one by one from the test condition of 60 kVp, 200 mA, 0.1sec and 100 kVp, 200 mA, 0.1 sec. At 60 kVp, 2 lead oxide-barium sulfate shields, 2 bismuth oxide 1.5 mm shields, and 5 bismuth oxide 0.3 mm shields showed shielding ability equal to or higher than that of lead 0.5 mm. At 100 kVp, 2 lead oxide-barium sulfate shields and 2 bismuth oxide 1.5 mm shields showed shielding ability equal to or higher than that of lead 0.5 mm. It was confirmed that when using 2 pieces of lead oxide-barium sulfate and 1.5 mm of bismuth oxide, respectively, it has shielding ability equivalent to that of lead. Bismuth oxide and lead oxide-barium sulfate are lightweight and have excellent shielding ability, thus they have excellent properties to be used as an apron for radiation protection or other shielding materials.

The Identification, Diagnosis, Prospective, and Action (IDPA) Method for Facilitating Dialogue between Stakeholders: Application to the Radiological Protection Domain

  • Jacques Lochard;Win Thu Zar;Michiaki Kai;Ryoko Ando
    • Journal of Radiation Protection and Research
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    • 제48권3호
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    • pp.107-116
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    • 2023
  • This article reviews the experience of applying the Identification, Diagnosis, Prospective, and Action (IDPA) facilitating method as a means of promoting practices of dialogue between stakeholders in the radiological protection field. After presenting the characteristics of the IDPA method and its ability to promote active listening, participation, and dialogue among stakeholders facing complex situations, as well as the procedural aspects associated with its practical implementation, the article describes three examples of the application of the method in the field of radiological protection. The first one presents how the IDPA method supported a debate among decision-makers, authorities, experts, professionals, and representatives of non-governmental organizations about how to engage stakeholders in radiological protection. The second example presents how the IDPA method was used in a series of dialogue meetings to explore the challenges of the post-nuclear accident situation resulting from the Fukushima Daiichi Nuclear Power Plant accident. The third one presents the application of the method in the context of a training course organized by Nagasaki University in the affected area close to the damaged plant. Experience has shown that the IDPA method makes it possible to develop responses to problems posed in very different contexts and, in many cases, to find compromises regarding their solutions. The IDPA method has the merit of allowing each of the participants to better understand the situation they are faced with, even if such a positive result is not always achieved.

KSLV-I PLF 음향 하중 저감 시스템의 성능 검증을 위한 음향 시험 (Acoustic Test of KSLV-I PLF Acoustic Protection System)

  • 박순홍;서상현
    • 항공우주기술
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    • 제7권2호
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    • pp.117-122
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    • 2008
  • KSLV-I PLF의 음향 하중 저감 시스템의 성능을 검증하기 위해 음향 시험을 수행하였다. 실측한 음향 하중 저감치를 설계 기준과 비교하여 약 3dB 이상의 안전여유를 확보하고 있음을 알 수 있었다. 또한 음향 하중 저감 시스템을 적용하지 않은 PLF 구조체에 대한 음향 시험을 통해 음향 하중 저감 시스템에 의한 삽입 손실 증가치도 예시하였다.

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송전선 보호용 차동전류 계전기의 동작원리에 대한 그래픽 표현 (Graphical Modeling for Operational Scheme of Current Differential Relay for Transmission Line Protection)

  • 이종범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 C
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    • pp.1407-1409
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    • 1999
  • Distance relay is being used for transmission line protection. Recently, current differential relay is used with high reliability in power system. This kind of relay is reported that it has a reliable detection ability, even so high impedance faults take place in transmission line. Therefore it is expected to use and expand widely in many utilities. Tripping of the relay is decided according to the difference between differential and restraint current. However the tripping criterion can be changed by the manufacturers. This paper presents an operational scheme of current differential relay for transmission line protection with graphical model. It is developed for educational purpose for students interesting in power system and protection engineer in utility. MATLAB is used to establish the models.

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사이버 방호기능 분석을 통한 지휘통제에 관한 연구 (A Study on Command and Control Through Cyber Protection Function Analysis)

  • 최세호;오행록;윤주범
    • 한국군사과학기술학회지
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    • 제24권5호
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    • pp.537-544
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    • 2021
  • Cyber threats can bypass existing cyber-protection systems and are rapidly developing by exploiting new technologies such as artificial intelligence. In order to respond to such cyber threats, it is important to improve the ability to detect unknown cyber threats by correlating heterogeneous cyber protection systems. In this paper, to enhance cyber-attack response capabilities, we proposed command and control that enables rapid decision-making and response before the attack objectives are achieved, using Lockheed Martin's cyber kill chain and MITRE ATT&CK to analyze the purpose and intention of the attacker.

포러스콘크리트의 골재입도 및 공극률에 따른 식생능력평가 (Planting-Ability Properties of Porous Concrete as Gradation and Void Ratio)

  • 윤덕열;김정환;조영수;표구영;박승범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.243-248
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    • 2002
  • As a notion of environment protection changes throughout the world, construction engineers, as part of the effort to resolve environmental problems, have been actively doing research on environmental friendly porous concrete using large and non-uniform aggregate. Porous Concrete enables water and air to pass through a firmly hardened material and allows required nutrients to reach roots of plants. The purpose of this study is to analyze planting ability when the change of aggregate gradation and void ratio. The results of an experiment from the planting ability of the porous concrete to its influence on the compressive strength are reported in this paper. As a result of the experiment, the compressive strength is higher when the gradation of aggregate is smaller, and it also goes higher when the void ratio gets smaller The planting ability of porous concrete is decided by the germination and the grass length of Indigofera pseudo-tinctoria(IPT). The length of IPT is longer when the gradation of aggregate is greater and the void ratio gets smaller.

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유산균의 항산화 활성 비교 (Comparative Study of Lactic Acid Bacteria for Antioxidative Activities)

  • 조윤희;오세종
    • Journal of Dairy Science and Biotechnology
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    • 제28권2호
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    • pp.31-39
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    • 2010
  • Lactic acid bacteria (LAB) are typical probiotic microbes which are used in various industries including fermented foods, feed additives, and pharmaceuticals. The purpose of this study was to compare the ability of antioxidative activities of 23 strains of LAB isolated from cheese, kimchi, yogurt, and etc. LAB were tested for antioxidative activities such as 2,2'- azino-bis(3-ethyl-benzothiazoline-6-sulphonic acid) (ABTS) radical scavenging abilities and superoxide dismutase (SOD)-like ability. Antioxidative activities were examined different media such as MRS, M17, and 10% skim milk. Culture supernatant in M17 medium showed a higher antioxidative activity than these in MRS and 10% skim milk. Comparison of ABTS radical scavenging ability by the LAB showed a wide variation with a range from 9~93% and SOD-like ability of LAB ranged from 70~78%, respectively. Therfore, some of LAB can play important roles in the protection for oxidative stress and CPP-producing activity of LAB may be a promising material for application in the dairy industry.

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