排序方式: 共有16条查询结果,搜索用时 31 毫秒
1.
2.
为检查和评价隧道及地下空间火灾预警系统的实际功能,需要一套可行的在线评估手段。根据近年来国内外全尺寸隧道火灾发展曲线的试验结果,提出隧道火情的定义依据;引用运营隧道内准分布式光纤光栅感温火灾探测器的实测数据,证明运营中隧道报警系统的个性化现象;提出合格的数字化报警系统应存在一个在统计学意义上使漏报率和误报率同时达到期望值的合理阈值取值区间;建议以该区间的尺度作为该系统功能完好性的评估指标;对日常隧道运行温度数据的统计分析可估计合理阈值取值区间的下限,对规定条件下的现场点火试验温度数据分析可估计合理阈值取值区间的上限。在隧道运营期该区间尺度可实时在线自动更新。 相似文献
3.
4.
5.
6.
利用干纺丝工艺,采用溶胶-凝胶法结合化学模板法制备了Ce0.5 Zr0.5 O2纳米多孔纤维,并在此基础上采用传统抄纸法制备了Ce0.5 Zr0.5 O2纤维纸。通过引入SiO2、TiO2和Al2 O3作为支撑体,利用XRD、低温N2吸附、拉曼光谱等手段分析了Ce0.5 Zr0.5 O2纳米多孔结构性能的变化。在空气条件下通过循环热失重分析法测定了材料在300~800℃温度范围内的氧储存能力,Ce0.5 Zr0.5 O2纳米多孔纤维的氧储存能力受到包括材料的比表面积、结晶程度以及支撑体性质等多方面因素的影响。 相似文献
7.
8.
An investigation is presented on the performance of a small-scale solar power and heating system with short parabolic trough collectors (PTCs). The steady-state model of the short PTCs is evaluated with outside experiments. The model mainly contains the heat loss of the receiver, the peak optical efficiency and the incident angle factor consisting of incident angle modifier and end loss. It is found that the end loss effect is essential in this model when the length of the PTCs is less than 48 m, especially in the winter. The standard deviation of the steady-state model is 1.4%. Moreover, the potential energy efficiency ratio of the solar power and heating system is considerably larger than the coefficient of performance (COP) of general air-source heat pumps, and increases with the decrease of the condensation temperature. An overall system efficiency of 49% can be reached. Lastly, the existence of a water storage tank improves the flexibility of heating the building, and the volume of the water storage tank decreases with the increase of the heating water temperature. 相似文献
9.
10.