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81.
当前概念设计中较大规模功能树存在解空间庞大、冲突定位困难的问题,对此提出基于与或功能树的无损简化方法。证明了无损收缩简化、无损删除简化、无损提取简化的相关定理,并籍此给出与或功能树的无损简化算法。最后通过实例,证明该算法可在保持逻辑等价和创新能力不损失的前提下有效降低问题的复杂度,从而提高了概念设计的效率。 相似文献
82.
Stress corrosion crack growth rates of 304L stainless steel after one-directionally warm-rolled along the longitudinal (L) direction were measured in oxygenated and deoxygenated pure water at 288 °C. The fracture mode is mainly intergranular in the Transverse-longitudinal (T-L) orientation specimen, while it is occasionally intergranular in the Longitudinal-transverse (L-T) orientation specimen. The crack growth rates in the T-L orientation are higher than those in the L-T orientation in both oxygenated and deoxygenated environments, which is related to the effective cracking growth path as the result of microstructural anisotropy and applied loading direction. 相似文献
83.
介绍了以环戊烷为发泡剂的冰箱高压发泡模塑生产成套设备的安全设计原则和具体实施内容,重点介绍了环戊烷/多元醇预混系统、聚氨酯环戊烷高压发泡机和聚氨酯冰箱发泡模塑生产线的安全要点。 相似文献
84.
以城、郊为界将北京公路绿化状况分为两部分,并进行了分析比较,从而找出两者现状差异,并根据效区公路绿化中的不足,从提高认识、加大投入、合理设计、科学养护4个方面找到解决问题的方法。 相似文献
85.
86.
Shangyang Xiao Weihong Qiu Jun Liu Thomas X. Wu Issa Batarseh 《International Journal of Electronics》2013,100(1):51-61
Traditional current sensing topology based on inductor equivalent series resistance fails to extract phase currents for coupled inductors due to the presence of the magnetising inductance. This article proposes a new direct-current resistance current sensing topology for coupled inductors. By implementation of a simple resistor-capacitor network, the proposed topology can preserve the coupling effect between phases. As a result, real phase inductor currents and total current can be sensed. Detailed mathematical analysis and design equations are presented in this article. Sensitivity and mismatch issues are addressed. Experimental results show that the proposed topologies are able to extract phase current as well as total current with acceptable accuracy. 相似文献
87.
88.
Pei-Nan Ni Jin-Chao Tong Landobasa Y. M. Tobing Shu-Peng Qiu Zheng-Ji Xu Xiao-Hong Tang Dao-Hua Zhang 《Journal of Electronic Materials》2017,46(7):3867-3872
We present a simple thermal treatment with the antimony source for the metal–organic chemical vapor deposition of thin GaSb films on GaAs (111) substrates for the first time. The properties of the as-grown GaSb films are systematically analyzed by scanning electron microscopy, atomic force microscopy, x-ray diffraction, photo-luminescence (PL) and Hall measurement. It is found that the as-grown GaSb films by the proposed method can be as thin as 35 nm and have a very smooth surface with the root mean square roughness as small as 0.777 nm. Meanwhile, the grown GaSb films also have high crystalline quality, of which the full width at half maximum of the rocking-curve is as small as 218 arcsec. Moreover, the good optical quality of the GaSb films has been demonstrated by the low-temperature PL. This work provides a simple and feasible buffer-free strategy for the growth of high-quality GaSb films directly on GaAs substrates and the strategy may also be applicable to the growth on other substrates and the hetero-growth of other materials. 相似文献
89.
Yi Qiu Ruixiang Peng Jingyu Shi Zhenyu Chen Ziyi Ge 《Advanced functional materials》2023,33(28):2300831
Inverted organic solar cells (i-OSCs) provide an exciting opportunity for commercialization owing to their excellent device air stability. However, light soaking (LS) issue generally occurs in metal oxide based i-OSCs, causing drastically decreased performance. The underlying root of LS effect is not clearly clarified until now. Herein, it is demonstrated that the surface oxygen defects on metal oxide nanoparticles, such as chemisorbed superoxide (O2−) and hydroxide (OH) dangling bonds, are the main reasons for LS issue in i-OSCs. The O2− layer induces band bending at the cathode interface and increases the work function (WF) of metal oxide, thus leading to inefficient charge transport. The dangling bonds serve as interfacial trap states and cause non-radiative recombination, thus leading to the reduced open circuit voltage (Voc). With ultraviolet (UV) illumination, the surface oxygen defects are interacted with photogenerated carriers, thereby improving the photovoltaic performance. Additionally, UV pretreatment of metal oxide films is employed to eliminate the LS issue and the resulting device yields significantly improved fill factors from 50.20% to 73.50% in the pristine SnO2 based i-OSCs. This study reveals the origin of LS effect in i-OSCs and proposes a suggested model for LS mechanism. 相似文献
90.
RGBW滤光阵列常被用于提升探测器在低照度下的成像质量,但相应的彩色重构方法依然是结合拜尔阵列特点设计的,未充分利用亮度信息的优势,故重构结果较差.针对这一缺陷,首先,使用引导滤波挖掘亮度信息和彩色信息的关联性.然后,根据残差的平滑性,设计了适用于SONY-RGBW滤光阵列空域特点的采样率逐步提升的多步残差插值算法.接... 相似文献