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971.
结合提升静态小波和灰色关联分析的图像融合算法 总被引:2,自引:1,他引:1
本文针对多聚焦图像,提出了一种基于提升静态小波变换(lifting stationary wavelet transform,LSWT)和灰色关联度相结合的图像融合算法。首先将待融合的两幅图像分别进行提升静态小波变换,低频分量采用平均法融合,其次再针对低频分量和各个方向的高频分量,分别计算以每个像素为中心的方块的能量和均值,然后计算低频分量的能量和均值构成的序列与高频分量的能量和均值构成的序列之间的灰色欧几里德关联度。按照一定的融合规则,分别得到高频分量融合后的值,最后进行提升小波逆变换,得到融合后的图像。实验结果显示,该方法融合效果较好,优于传统算法。 相似文献
972.
973.
《Microelectronics Reliability》2015,55(2):418-423
The wafer warpage problem, mainly originated from coefficient of thermal expansion mismatch between the materials, becomes serious in wafer level packaging as large diameter wafer is adopted currently. The warpage poses threats to wafer handling, process qualities, and can also lead to serious reliability problems. In this paper, a novel mechanical diced trench structure was proposed to reduce the final wafer warpage. Deep patterned trenches with a depth about 100 μm were fabricated in the Si substrate by mechanical dicing method. Both experiment and simulation approaches were used to investigate the effect of the trenches on the wafer warpage and the influence of the geometry of the trenches was also studied. The results indicate that, by forming deep trenches, the stress on the individual die is decoupled and the total wafer warpage could be reduced. The final wafer warpage is closely related to the trench depth and die width. Trenched sample with a depth of 100 μm can decrease the wafer warpage by 51.4%. 相似文献
974.
975.
The Effect of Gradual Fluorination on the Properties of FnZnPc Thin Films and FnZnPc/C60 Bilayer Photovoltaic Cells
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Michael Brendel Stefan Krause Andreas Steindamm Anna Katharina Topczak Sudhakar Sundarraj Peter Erk Steffen Höhla Norbert Fruehauf Norbert Koch Jens Pflaum 《Advanced functional materials》2015,25(10):1565-1573
Motivated by the possibility of modifying energy levels of a molecule without substantially changing its band gap, the impact of gradual fluorination on the optical and structural properties of zinc phthalocyanine (FnZnPc) thin films and the electronic characteristics of FnZnPc/C60 (n = 0, 4, 8, 16) bilayer cells is investigated. UV–vis measurements reveal similar Q‐ and B‐band absorption of FnZnPc thin films with n = 0, 4, 8, whereas for F16ZnPc a different absorption pattern is detected. A correlation between structure and electronic transport is deduced. For F4ZnPc/C60 cells, the enhanced long range order supports fill factors of 55% and an increase of the short circuit current density by 18%, compared to ZnPc/C60. As a parameter being sensitive to the organic/organic interface energetics, the open circuit voltage is analyzed. An enhancement of this quantity by 27% and 50% is detected for F4ZnPc‐ and F8ZnPc‐based devices, respectively, and is attributed to an increase of the quasi‐Fermi level splitting at the donor/acceptor interface. In contrast, for F16ZnPc/C60 a decrease of the open circuit voltage is observed. Complementary photoelectron spectroscopy, external quantum efficiency, and photoluminescence measurements reveal a different working principle, which is ascribed to the particular energy level alignment at the interface of the photoactive materials. 相似文献
976.
中国航信高科技产业园区数据中心是近期完成的规模最大、等级最高的数据机房类项目之一。其初步设计是与外方联合设计的,又是以“UptimeInstitute数据中心标准”、“ANSI/TIA-942标准”为依据,同时参照了我国“电子信息系统机房设计规范GB50174—2008”来设计的。因此与早期的设计相比有了一些进步,现就其中的一些主要设计原则和电气系统做一介绍。 相似文献
977.
中国航信高科技产业园区数据中心是近期完成的规模最大、等级最高的数据机房类项目之一。其初步设计是与外方联合设计的,又是以“UptimeInstitute数据中心标准”、“ANSI/TIA-942标准”为依据,同时参照了我国“电子信息系统机房设计规范GB50174—2008”来设计的。因此与早期的设计相比有了一些进步,现就其中的一些主要设计原则和电气系统做一介绍。 相似文献
978.
目的 探讨高血铅对幼儿神经行为的影响.方法选择血铅≥100 μg·L-1的33例儿童作为高血铅组,血铅<100 μg·L-1的33例儿童作为对照组.采用幼儿行为量表对2组儿童的社交退缩、忧郁、睡眠问题、躯体诉述、攻击、破坏6个行为因子进行评分.结果 高血铅组发生忧郁、攻击的比例分别为45.5%、81.8%,显著高于对照组的12.1%、48.5%(P<0.01).高血铅组行为因子总得分为(60.36±27.66)分,对照组为(41.73±23.84)分,高血铅组显著高于对照组(Z=-2.937,P=0.003);2组社交退缩、忧郁、躯体诉述、攻击、破坏5个行为因子得分比较差异均有统计学意义(P<0.05).结论 高血铅儿童发生神经行为异常较正常儿童增多,对高血铅儿童采取积极有效的预防、干预措施,是儿童健康成长的重要保证. 相似文献
979.
《The IES Journal Part A: Civil & Structural Engineering》2013,6(4):265-275
In recent studies, the uniform simplified distribution blast load and numerical simulation have proven to be prevalent in the use of investigating structural components dynamic behaviour during blast events, whilst neglecting the negative phase pressure. This study compares the steel column's response during the total pressure period to that of its response during only the positive stage. Moreover, the real blast pressure has varying values depending on the point distance and explosion incident angle. The real blast load curve was derived by using a specialised program to calculate pressure at different points on the steel column vertical line; and the results were used to compare its impact with the uniform and concentrated cases. Also ABAQUS finite element code was used to check the validity of the single-degree-of-freedom (SDOF) analysis method when the column is subjected to axial and transverse blast loads. The obtained results show the SDOF inability through dynamic reaction calculations. In addition, SDOF has limitations in dealing with dynamic steel response when the axial load ratio was greater than 0.5. Damage prediction methods and equations were introduced through different concepts and the ductility ratio was used to estimate the damage level of 100 kg TNT at 4.5 m stand-off distance. The strain rate effects were included in the material with different scenarios based on the dynamic increase factor. 相似文献
980.
伴随着我国城市化速度的加快,城市中建筑物的分布越来越密集,建筑物的高度、基坑深度也在逐渐增加。在基坑开挖时可视情况采用更加合理的支护技术,以保证施工安全,节约工程成本。 相似文献