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51.
The primary goal of this research is to provide recommendations for the eventual development of more effective and efficient fire sensors to be installed in space vehicles and habitats. An entirely new ground-based testing facility that generated fire signatures was developed to perform the combustion and pyrolysis experiments of eight different practical spacecraft materials. The flaming and smoldering of polymers approved by the National Aeronautics and Space Administration (NASA) generate three types of residues: condensables, light gases, and particulates. The residues were characterized by gas chromatography (GC), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The analysis was interpreted as a function of oxygen concentration, temperature, and flow direction. Key findings are that the combustion of some materials such as Kevlar and cotton can only be identified by light gases, while the combustion of other materials, such as silicone and melamine, is best detected using a particulate-specific sensor. The implications during a fire event, its suppression, astronaut health in post-event cleanup as well as material recommendations are briefly discussed. 相似文献
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《Ergonomics》2012,55(5):502-512
Six well-trained firefighters performed six treadmill runs at 70% of the velocity at VO2max (Maximal aerobic velocity MAV = 13.26±0.3 km h-1). A recovery time of 1 week was allowed between trials. The first session was performed by subjects wearing only shorts (i.e. no fire jacket, J0). A similar protocol was applied subsequently to test the physiological eOEects associated with the wearing of one of five different fire jackets: one leather (J1) and four textile-type jackets: VTNTM with membrane (J2), VTNTM without membrane (J3), VidalTM with Kermel® HTA (Haute Teneur en Aramide i.e. high density in Aramide) (J4); and RollandTM with Kermel® HTA (J5). All sessions were performed in a randomized order and in laboratory conditions. Exercise with the fireproof jackets resulted in higher tympanic temperature (Tty), heart rate (HR) and body mass loss (BML) changes compared to J0 (p <0.001). The magnitudes of these changes depended on the type of the jacket. Exercise in the leather jacket (J1) resulted in the highest Tty and HR, which diOEered significantly from values in all other conditions (p<0.001). The exercise-induced increases in Tty wearing jackets J3 and J5 were also significantly (p<0.05) higher than those observed with jackets J2 and J4. In conclusion, textile jackets induced less HR and Tty stresses than the leather one. The magnitude of the physiological responses induced by textile jackets were correlated to jacket weight. J2 and J4 jackets were more effective in limiting hyperthermia and any potential detrimental effect on the exercise capacity. 相似文献
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廖仲春 《湖南工业职业技术学院学报》2010,10(6):130-131
高等职业教育规模的迅猛发展,招生总量持续增长,导致高职人才培养质量下降。建立教学质量监控体系,是高职院校面临的紧迫任务。文章运用项目管理中戴明环PDCA循环的管理运作方式,建立教学质量监控体系,将对提高教学质量起到良好的促进作用。 相似文献
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印染机械多电机同步控制系统 总被引:6,自引:3,他引:6
根据印染工业的工艺特点 ,研究与开发了一种用PLC和数字检测实现的同步控制装置。该装置具有较高的精度和可靠性 ,并且结构简单、可扩展性强 ,可以在生产应用中推广。 相似文献
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论述一种适用于在狭窄巷道、低矮采掘环境中进行短距离装载、运输作业的井下装载机的设计要点,这种装载机的工作装置、前车架、后车架、传动系统、燃油箱、液压系统与普通装载机通用。详细论述非通用件的设计,其中包括地板、仪表台、座椅支架、转向操纵机构、驾驶棚、电气系统和发动机的消声、灭火、除烟尘装置及启动系统等部件,以及防火、防爆、瓦斯监测的设计要点和具体结构。 相似文献
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Yu Yan Jiang Eiji Yanai Kazumi Nishimura Huilai Zhang Nobuyuki Abe Masahiko Shinohara Kaoru Wakatsuki 《Fire Safety Journal》2010
Research and development of firefighters’ protective clothing relies on a large number of fire disaster experiments in order to assess the thermal performance. It would be substantially advantageous to substitute a virtual numerical experiment for a real one in terms of time, cost and safety. The present article reports the development of an integrated numerical simulator that makes possible the estimation of burn injuries originating from fire disasters. In the simulator, a general-purpose computational fluid dynamics program computes the fluid flow and heat transfer in an in situ fire event, while a one-dimensional program calculates the radiative–conductive heat transfer through the clothing and human skin. A data interface combines the two simulations by loose coupling so as to give the real-time burn injury progress output. The predicted surface heat fluxes and burn degrees agree with experimental measurements reasonably well. Possible numerical error sources are discussed that call for potential improvements in the future. 相似文献
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Fire and cork can be considered both the most serious problem and the most valuable resource of Portuguese forests. The existence of important areas of burned cork oak stands resulting from severe fire seasons in recent years is an environmental problem which deserves special attention. This paper makes a multidisciplinary survey of the problem of burned cork oak stands focusing on: the dimensions of the problem in Portugal, the remarkable resistance of cork oak to fire, the post‐fire management of cork oak stands, and the economic and ecological effects of fire in cork oak stands. Particular emphasis is given to knowledge gaps in this context. 相似文献