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101.
首先推导了粗糙洋面双向偏振反射模型pBRDF(Bidirectional Polarized Reflectance Distribution Function),并将其与SOSVRT(Successive Order of Scattering Radiative Transfer)矢量辐射传输模式耦合,建立了海洋-大气耦合的矢量辐射传输模式,并对该耦合模式的模拟结果与前人模拟结果进行对比,验证了该耦合模式的可靠性与有效性。不同大气和洋面状态、不同高度的主平面内辐射强度和偏振度的模拟结果表明:pBRDF模型可以很好地模拟不同风速下洋面的偏振反射分布特征;洋面在特定角度具有很高的偏振度,并对大气顶的偏振辐射有很大影响。因此,该耦合模式可以更准确地处理辐射光谱在海洋-大气两种介质间的传输问题,对矢量辐射传输、大气遥感问题的研究有重要意义。 相似文献
102.
十二烷基苯磺酸钠水溶液聚集性质的研究 总被引:8,自引:0,他引:8
用滴体积法测出十二烷基苯磺酸钠(SDBS)稀水溶液的表面张力;然后求出其临界胶束浓度(CMC)。同时通过溶液的电导率、吸收光谱以及荧光光谱测定求出其CMC。这样测出的CMC值为1.2~1.6×10-3mol/L,与文献值相符。也研究了部分水解的聚丙烯酰胺(PHPAM)对SDBS聚集性质的影响;发现SDBS的CMC值随PHPAM的加人而减少并且PHPAM水溶液的粘度随SDBS的存在而急剧降低(类似盐效应)。这些方法与性质对强化采油(EOR)是重要的。 相似文献
103.
Mehdi Qasim Jinan Al‐Dabbagh Naser Mahmoud Ahmed V.G. Chigrinov Gurumurthy Hegde 《Journal of the Society for Information Display》2014,22(4):187-190
Indium tin oxide‐coated thin films (200 nm) are deposited on glass substrates by using R.f. sputtering technique. Here, we investigate the influence of new technique of treatment, which is called as “oil thermal annealing” on the nano‐structured indium tin oxide thin films at fixed temperature (150 °C) which improves adhesion strength, electrical conductivity and optical properties (transmittance) of the films. Oil thermal annealing is used to reduce inherent defects that may be introduced during the prepared thin film and cooling processes. Proposed technique is highly suitable for liquid crystal displays, solar cells and organic light emitting diodes, and many other display‐related applications. 相似文献
104.
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized. 相似文献
105.
数控超声磨削陶瓷叶片型面刀位轨迹计算 总被引:1,自引:0,他引:1
介绍了陶瓷超声磨削加工现状,建立了平行直纹面数学模型.分析了用圆柱磨轮四轴数控超声磨削平行直纹面时原理误差,并提出减小误差的措施,计算出磨轮空间轨迹,并进行陶瓷叶片型面超声磨削加工工艺试验.试验结果表明,超声磨削加工陶瓷叶片型面是可行的,所完成的刀位计算可有效减小原理误差. 相似文献
106.
Surface performance of workpieces processed by electrical discharge machining in gas 总被引:1,自引:0,他引:1
The surface performance of workpieces processed by electrical discharge machining in gas(dry EDM)was studied in this paper.Firstly,the composition,micro hardness and recast layer of electrical discharge machined(EDMed)surface of 45 carbon steels in air were investigated through different test analysis methods.The results show that the workpiece surface EDMed in air contains a certain quantity of oxide,and oxidation occurs on the workpiece surface.Compared with the surface of workpieces processed in kerosene,fewer cracks exist on the dry EDMed workpiece surface,and the surface recast layer is thinner than that obtained by conventional EDM.The micro hardness of workpieces machined by dry EDM method is lower than that machined in kerosene,and higher than that of the matrix.In addition,experiments were conducted on the surface wear resistance of workpieces processed in air and kerosene using copper electrode and titanium alloy electrode.The results indicate that the surface wear resistance of workpieces processed in air can be improved,and it is related with tool material and dielectric. 相似文献
107.
In a field study P and K uptake by two corn (Zea mays L.) genotypes which differed in root growth was investigated. The effect of differences in root growth on P and K uptake was assessed using a mechanistic-mathematical model which describes nutrient uptake by growing plant roots in soil. Nitrogen was applied at 0 and 227 kg ha–1 to Pioneer 3732 and B73xMo17 corn grown on Raub silt loam (fine-silty, mixed, mesic Aquic Argiudoll) and at 227 kg N ha–1 to these two genotypes on Chalmers silt loam (finesilty, mixed, mesic, Typic Haplaquoll). Root growth and P and K uptake by the two corn genotypes was measured 31, 47, 75 and 91 d after planting on the Raub and 31, 47, 61 and 75 d after planting on the Chalmers soil.Root growth and P and K uptake by B73xMo17 was greater than that of Pioneer 3732 on N-fertilized Raub soil. On Chalmers soil the difference in root growth between the two genotypes resulted in an increase in K but not P uptake. The higher soil P level of the Chalmers appears to have offset possible differences in P uptake due to root size. There were no differences between the two genotypes in either the percentage of roots with root hairs, or the density or length of root hairs. Phosphorus and K uptake calculated with the simulation models for both corn genotypes on both soils over each of three growth periods agreed with observed P (Y = 0.68X + 1.71; r = 0.944**) and K (Y = 0.88X + 15.52; r = 0.928**) uptake. Differences in P and K uptake between B73xMo17 and Pioneer 3732 resulted primarily from the difference in root growth in the topsoil. A high correlation was found between root surface area and P (r = 0.893**) and K (r = 0.928**) uptake by both corn genotypes on both the soils.Journal paper No. 10,316 Purdue Univ. Agric. Exp. Stn., W. Lafayette, In 47906. Contribution from the Dep. of Agron. This paper was supported in part by a grant from the Tennessee Valley Authority. 相似文献
108.
针对传统的表面缺陷检测方法只能对具有高对比度或低噪声的明显缺陷轮廓进行检测的问题,提出了一种基于自编码和知识蒸馏的表面缺陷检测方法来准确定位和分类从实际工业环境捕获的输入图像中出现的缺陷。首先,设计了一种级联自动编码器(CAE)架构用于分割和定位缺陷,其目的是将输入的原始图像转换为基于CAE的预测蒙版;其次,利用阈值模块对预测结果进行二值化以获得准确的缺陷轮廓;然后,把缺陷区域检测器提取并裁剪出来的缺陷区域视为下一个模块的输入;最后,将CAE分割结果的缺陷区域通过知识蒸馏进行类别分类。实验结果表明,与其他几种表面缺陷检测方法相比,所提出的方法综合性能最好,其缺陷检测平均准确率为97.00%。该方法能够有效地对较小的、边缘不清晰的缺陷进行分割,满足对物品表面缺陷实时分割检测的工程要求。 相似文献
109.
《矿业科学技术学报(英文版)》2016,26(6):1117-1123
In order to study the influence of depth-thickness ratio on bedding slope stability, whose sliding surface is flexural concave in shape under mining conditions, this paper aims to study the characteristics of deformation and damage of bedding sliding with depth-thickness ratios of 200:1, 150:1, 120:1, 100:1 and 50:1by adopting numerical simulation analysis software combined with laboratory-made ‘‘under the influence of mining variable sliding surface slope similar simulation test bed", and to propose identification methods for slope stability under the influence of mining. The results show that mining activities under the slope reduce slope stability. With a decrease in the mining depth ratio, the influence of mining on the slope increases gradually, and the damage to the slope gradually expands, the stability of the slope gradually reduces, fracture occurs on the slope toe and the central fissure gradually develops to the surface,and reaches slide threshold when the depth-thickness ratio is 50:1. 相似文献
110.
该文提出了一种可以广泛应用于四阶PDE曲面的裁剪方法。利用PDE的参数域内的曲线在曲面上投影,得到所求裁剪曲面的边界曲线,然后通过边界曲线的导矢与曲面在边界曲线处的法向量得到边界曲线处的跨界导矢,最后以求得的裁剪曲面的边界曲线以及裁剪曲面在边界曲线处的跨界导矢为PDE曲面的边界条件,用四阶的PDE曲面方程求得PDE裁剪曲面。 相似文献