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11.
在发生火灾等紧急情况时,由于高层楼宇空间小、出口少的结构特性,受困人员逃生往往很困难。针对传统的被动引导逃生方式中信息获取有限、易产生人群聚集等缺点,该文提出主动式逃生导航的概念,设计了一种改进的K-Means室内定位方法,结合人群密度检测与环境信息采集,进行路径导航,实现了一套基于传感器网络与智能手机的定位导航系统。实验表明,该系统能较好地提高定位精度,避开火灾点,增大每个人的逃生几率,该文为室内逃生导航方案提供了新的思路。 相似文献
12.
在载人航天任务中,保障航天员的生命安全是地面逃逸安控系统的首要任务,该系统具有高可靠性、高安全性.因此,对其可靠性进行研究十分必要.主要研究了逃逸安控系统可靠性技术,包括数据接收与处理、逃逸安控软件、指挥模式与指令发送等几个关键环节的可靠性,提出了提高系统可靠性的方法和措施,完善了地面逃逸安控系统可靠性设计,为圆满完成后续载人飞行任务打下良好基础. 相似文献
13.
地球、金星大气寿命的计算 总被引:2,自引:0,他引:2
假定行星大气层中气体分子的逃逸过程是准静态过程,推导出了气体分子的逃逸方程,定义了行星大气分子的逃逸率及行星大气的半寿命,给出了数学表达式.根据数学表达式,假定不同的大气温度,计算了地球和金星大气层的半寿命.结果表明,地球和金星大气层的半寿命远超过宇宙年龄(约1010y),因而是非常稳定的.本理论可应用于其他行星和月球大气层半寿命的计算. 相似文献
14.
15.
Vierck Charles J. Jr.; Kline Robert IV; Wiley Ronald G. 《Canadian Metallurgical Quarterly》2004,118(3):627
In behavioral tests, rats performed learned escape responses to thermal stimulation of the paws by 44.0. 47.0. or 0.3 degrees C. Licking, guarding, and jumping reflexes were evaluated at these temperatures. The frequency, latency, and duration of escape and reflex responses were compared and were related to hind-paw skin temperatures measured during stimulation of awake and anesthetized rats. The duration and latency of escape from heat were appropriately related to stimulus intensity. Escape occurred reliably for each intensity. Reflexes occurred unreliably and at long latency to 44.0 or 0.3 degrees C and were not appropriately related to heat intensity. The reflexes were relatively insensitive to thermal nociceptive stimulation other than heating of the skin at a high rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
Gen Li Ulrike K. Müller Johan L. van Leeuwen Hao Liu 《Journal of the Royal Society Interface》2014,11(101)
Fish larvae may intercept their own wake during sharp turns, which might affect their escape performance. We analysed C-starts of larval zebrafish (Danio rerio, Hamilton, 1822) using a computational fluid dynamics approach that simulates free swimming (swimming trajectory is determined by fluid forces) by coupling hydrodynamics and body dynamics. The simulations show that fish may intercept their own wake when they turn by 100–180°. During stage 1 of a C-start, the fish generates a strong jet at the tail that is shed into the wake. During stage 2, the fish intercepts this wake. Counterfactual simulations showed that wake interception increased the lateral force on the fish and reduced the fish''s turning angle by more than 5°. Wake interception caused no significant acceleration tangential to the trajectory of the fish and did not affect total power output. While experimental and simulation evidence suggests that fish larvae can either undershoot or intercept but not overshoot their wake, our simulations show that larger fish might be able to avoid intercepting their wake by either under- or overshooting. As intercepting its own wake modifies the fish''s escape trajectory, fish should account for this effect when planning their escape route. 相似文献
17.
Wendy S. Smith David A. Johnston Harrison J. Wensley Suzanne E. Holmes Sopsamorn U. Flavell David J. Flavell 《International journal of molecular sciences》2020,21(22)
Cholesterol seems to play a central role in the augmentation of saporin-based immunotoxin (IT) cytotoxicity by triterpenoid saponins. Endolysosomal escape has been proposed as one mechanism for the saponin-mediated enhancement of targeted toxins. We investigated the effects of lipid depletion followed by repletion on Saponinum album (SA)-induced endolysosomal escape of Alexa Fluor labelled saporin and the saporin-based immunotoxin OKT10-SAP, directed against CD38, in Daudi lymphoma cells. Lipid deprived cells showed reduced SA-induced endolysosomal escape at two concentrations of SA, as determined by a flow cytometric method. The repletion of membrane cholesterol by low density lipoprotein (LDL) restored SA-induced endolysosomal escape at a concentration of 5 µg/mL SA but not at 1 µg/mL SA. When LDL was used to restore the cholesterol levels in lipid deprived cells, the SA augmentation of OKT10-SAP cytotoxicity was partially restored at 1 µg/mL SA and fully restored at 5 µg/mL SA. These results suggest that different mechanisms of action might be involved for the two different concentrations of SA and that endosomal escape may not be the main mechanism for the augmentation of saporin IT cytotoxicity by SA at the sub-lytic concentration of 1 µg/mL SA. 相似文献
18.
以目前福建省在建的泰宁隧道为例,介绍了大坡度斜井施工过程中的成功经验,包括对掏槽方式的优化,运输组织的合理设计,设置避险车道及避险平台等,可为今后类似工程提供有力指导。 相似文献
19.
避险车道设计及存在问题的分析简 总被引:2,自引:0,他引:2
通过对陕西省高速公路避险车道核查及国内多条高速公路避险车道调查,结合所从事避险车道设计的多年经验,从设计、施工及运营三个方面对目前国内现存避险车道存在问题进行分析,旨在从宏观方面为提高避险车道设计水平、提升施工质量、强化运营管理、完善避险车道功能等方面起到借鉴作用。 相似文献
20.
栅格翼国内外研究现状及发展趋势 总被引:2,自引:0,他引:2
介绍了国内外栅格翼的研制动态和发展趋势,讨论了栅格翼相对于传统平板翼的优势,最后结合国内研究现状,提出了开展栅格翼各方面研究的必要性. 相似文献