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21.
根据航站楼大空间特点,从电气设计角度,对航站楼大空间照明方式、照度、照度均匀度、光源的选择,配电(照明配电小母线的应用)、智能照明控制系统、钢屋盖系统灯具的维护等方面进行探讨和研究。 相似文献
22.
为研究层状饱和场地中沉积谷地对斜入射地震波的三维散射问题,建立了求解问题的2.5维间接边界元方法。通过沿沉积谷地轴线方向的傅里叶变换将三维问题降为二维问题,进而在沉积谷地的截面内进行边界单元的离散和求解,求得沉积谷地截面内的动力响应,然后再将截面内计算结果沿沉积谷地轴线方向进行波数展开即可求得任意位置动力响应。通过与弹性情况的比较验证了方法的正确性,并以均匀饱和半空间和基岩上单一饱和土层中沉积谷地对斜入射平面SH波的三维散射为例进行了数值计算和分析。研究发现沉积谷地对SH波的三维散射与二维散射之间存在显著差异;饱和情况(透水或不透水)与干土情况沉积谷地附近地表位移的差别很大;另外层状饱和半空间中沉积谷地和均匀饱和半空间中沉积谷地对斜入射SH波的放大作用也存在显著差别。 相似文献
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24.
介绍了2种液氯汽化技术——蒸汽间接加热法和热水间接加热法,分析了热水间接加热法的缺点,详细阐述了设计的蒸汽间接加热法的工艺流程、自动控制及安全系统。 相似文献
25.
为了解决常规间接蒸发冷却器由于表面水膜均匀性、完整性差而导致换热效率低的问题,提出了两侧旋转布水间接蒸发冷却器,进行了3种布置方式下的换热性能实验,运用正交实验对影响换热器性能的因素进行研究,研究表明:开孔正对气流方向时换热器换热性能最佳,且旋转布水装置存在最佳转速76r/min,喷水量、空气流速、冷却水流量、冷却水进口温度的增加使换热器的换热量增大,喷水温度、空气温度的升高使换热器的换热量减少,其中冷却水进口温度的改变对换热性能的影响最为显著,温度由35℃上升到39℃时,换热量提高37.62%,单位面积换热量为1.14kW,该换热器可安装于地下车站排风坑道内,可有效地解决地铁站冷却塔安装位置难题。 相似文献
26.
Kang-Won Wayne Lee Max Mueller Ajay Singh 《土木工程与建筑:英文版》2014,(6):680-692
Pavement rehabilitation and reconstruction methods with CIR (cold in-place recycling) are alternatives that can effectively reduce the high stresses and waste produced by conventional pavement strategies. An attempt was made to predict the performance, particularly low-temperature cracking resistance characteristics of CIR mixtures. These were prepared with the mix design procedure developed at the URI (University of Rhode Island) for the FHWA (Federal Highway Administration) to reduce wide variations in the application of CIR mixtures production. This standard was applied to RAP (reclaimed asphalt pavement) to produce CIR mixtures with CSS-Ih asphalt emulsion as the additive. By adjusting the number of gyrations of the SGC (Superpave gyratory compactor) for compaction, the field density of 130 pcf was represented accurately. To secure a base line, HMA (hot mix asphalt) samples were produced according to the Superpave volumetric mix design procedure. The specimens were tested using the IDT (indirect tensile) tester according to the procedure of AASHTO T 322 procedure at temperatures of-20, -10 and 0 ℃ (-4, 14, and 32°F, respectively). The obtained results for the creep compliance and tensile strength were used as input data for the MEPDG (mechanistic empirical pavement design guide). The analysis results indicated that no thermal or low-temperature cracking is expected over the entire analysis period of 20 years for both HMA and CIR mixtures. Thus, it appears that CIR is a sustainable rehabilitation technique which is also suitable for colder climates, and it is recommended to conduct further investigation of load-related distresses such as rutting and fatigue cracking. 相似文献
27.
Stelios Arvanitis 《时间序列分析杂志》2014,35(6):536-557
Indirect estimators usually emerge from two‐step optimization procedures. Each step in such a procedure may induce complexities in the asymptotic theory of the estimator. In this note, we are occupied with a simple example in which the estimator defined by the inversion of the binding function has a ‘discontinuous’ limit theory even in cases where the auxiliary one does not. This example lives in the framework of estimation of the MA (1) parameter. The ‘discontinuities’ involve the dependence of the rate of convergence on the parameter, the non‐continuity of the limit distribution w.r.t. the parameter and the estimator's non‐regularity. We are also occupied with a more complex example where the discontinuities occur because of complexities induced in any step of the defining procedure. We present some Monte Carlo evidence on the quality of the approximations from the limit distributions. Copyright © 2014 Wiley Publishing Ltd 相似文献
28.
To solve energy crisis, generation of clean and renewable energy sources are highly recommended. It not only solve energy‐related matters but also resolves environmental issues. A great number of renewable energy sources are present nowadays to resolve aforementioned issues, out of which photovoltaic modules is the preferable technology over others. Silicon is the native element to be used in photovoltaic module, due to its reasonable cost and band gap. The deciding parameters to harness solar energy to electricity rely upon solar irradiance and weather conditions. Here, we describe the rapid transformation of silicon as photovoltaic solar cell material that transfigured the photovoltaic industry. The photovoltaic industry initiated with monocrystalline silicon and multicrystalline silicon solar cell having conversion efficiency reached up to approximately 22.9% and 20.8%, respectively. The contemporary outburst for the trade of photovoltaic industry is due to the high manufacturing cost of silicon solar panels, which provided a chance for researchers to quest for advanced technology. It gave an opportunity for thin film solar cell to infiltrate in the market. This technology reduced the cost but on the expense of lower conversion efficiency. 相似文献
29.
传统的催化剂喷雾干燥系统多采用直接干燥工艺,载气与待干燥物料直接接触换热,这样会对某些特性的催化剂造成污染,影响产品的最终品质,且高温尾气不经回收直接排入大气,造成热量损失。基于此,开发了一种节能型催化剂清洁喷雾干燥技术,即:利用新型结构的间接式热风炉提供清洁的干燥热风,利用尾气半循环使部分高温清洁尾气回用,实现了节能型、清洁型喷雾干燥工艺。 相似文献
30.
《Food Control》2016
Competitive indirect enzyme-linked immunosorbent assay (ELISA) was developed for rapid detection of porcine gelatin in edible bird's nest (EBN). Three ELISAs were developed by using polyclonal rabbit antibodies against porcine species-specific amino acid sequences of collagen α2 (I) chain (pAb1 and pAb2) and α1 (I) chain (pAb3). The limit of detection (IC15) of the three ELISAs was 0.033, 0.082 and 0.052 μg/mL respectively. The median inhibitory concentration (IC50) of pAb1, pAb2 and pAb3 was 0.265, 0.394 and 0.228 μg/mL respectively, as well as able to recognise porcine and bovine gelatins. pAb1 showed slight cross-reactivity with cave nest and egg white, while pAb2 exhibited slight cross-reactivity with blood cave nest and egg white. No cross-reactivity was observed with EBNs and egg white for pAb3. The recoveries of porcine gelatin spiked EBNs were in the range of 62.8–125.4% with intra- and inter-day coefficient of variants (CVs) of 2.9–5.4% and 4.7–9.6% respectively when using pAb3. Taking into account all abovementioned factors, pAb3 appeared sufficient for EBN authentication. 相似文献