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Improving the precision of optical metrology by detecting fewer photons with biased weak measurement
Peng Yin Wen-Hao Zhang Liang Xu Ze-Gang Liu Wei-Feng Zhuang Lei Chen Ming Gong Yu Ma Xing-Xiang Peng Gong-Chu Li Jin-Shi Xu Zong-Quan Zhou Lijian Zhang Geng Chen Chuan-Feng Li Guang-Can Guo 《光:科学与应用(英文版)》2021,(6):1070-1077
In optical metrological protocols to measure physical quantities, it is, in principle, always beneficial to increase photon number n to improve measurement prec... 相似文献
54.
The formation and properties of precipitates in wrought Ni-based superalloys with different W contents during long-term exposure to high temperatures were inves... 相似文献
55.
岩体平巷充气降氡技术研究 总被引:2,自引:0,他引:2
提出了一种适用于破碎山体中平巷的降氡技术.该巷道中氡浓度受山体内空气渗流方向和强度的控制,渗流的机制是烟囱效应.由于山体内空气的温度基本恒定,因而密度不变,而巷道外空气密度随温度的变化而相应地变化着,这就导致了山体内外空气的失衡--夏季山体内含氡空气经裂缝流入巷道,冬季巷道外新鲜空气流入巷道后再经山体裂缝流向大气.实验表明,通过在巷道口部设置自动风门,向巷道内机械压风,形成充气状态,可以调节山体内空气的渗流方向,从而可以显著降低巷道内氡的浓度. 相似文献
56.
Lei Wang Xiaoqing Gong Yongqin Zhang Pengfei Xu Xiaojiang Chen Dingyi Fang Xia Zheng Jun Guo 《Multimedia Tools and Applications》2018,77(3):2973-2990
Chinese calligraphy is a unique visual art, and and is one of the material basis of China’s traditional cultural heritage. However, time had caused the old calligraphy works to weathering and damages, so it is necessary to utilize advanced technologies to protect those works. One of those technologies is digital imaging, and the obtained images by digital imaging can preserve the visual information of calligraphy works better, furthermore, they can be used in further researches. While the basic works for those researches are to extract the artistic features which include two elements, i.e., form and spirit. However, most of the existing methods only extract the form and ignore the characters’ spirit, especially they are insensitive to the slight variation in complex ink strokes. To solve these problems, this paper proposes an extraction method based on regional guided flter (RGF) with reference images, which is generated by KNN matting and used as the input image for RGF. Since RGF is sensitive to the slight variation of ink, so the detailed information of the inside of strokes can be detected better. Besides, unlike the past works, which filter the whole strokes, RGF filters the inside of strokes and edges in different windows respectively, which results in that the edges are preserved accurately. Results from a deployment of several famous Chinese calligraphy works demonstrate that our method can extract more accurate and complete form and spirit with lower error rate. 相似文献
57.
基于Petri网的联锁软件测评仿真建模 总被引:1,自引:0,他引:1
车站联锁软件一直有着严格的测试要求,仿真模块是软件测试的重要组成部分,Petri网作为形式化语言的一种,有着准确与完备的特点,对于联锁软件这类安全苛求软件的测试尤为适合,提出了一种使用Petri网对联锁软件测试中仿真模块建模的方式,并分别给出了用基本Petri网和有色Petri网的2个建模实例.该模型有助于提高铁路联锁软件测试系统的安全性与精确性. 相似文献
58.
全业务FTTx接入探讨 总被引:1,自引:0,他引:1
如今IP化和宽带化已成为大势所趋,面对高带宽、双向传输能力以及安全性等方面的更高要求,人们把关注的目光投向了FTTH,用光纤接入来突破接入带宽的瓶颈,是未来“最后一公里”的最终形式。本文结合EPON和GPON两种技术特色以及相关的多种因素和移动网络的现状对移动网络的FTTx建设进行探讨。 相似文献
59.
Chao-Fan Zhu Wei Guo You-Ping Wang Ya-Jun Li Hou-Jian Gong Long Xu Ming-Zhe Dong 《石油科学(英文版)》2021,(3):852-869
The fractures and kerogen,which generally exist in the shale,are significant to the CO2 huff-n-puff in the shale reservoir.It is important to study the effects ... 相似文献
60.
Yongjie Liu Dan Li Shengquan Zhang Liping Zhang Jie Gong Yanhong Li Jiamin Chen Fengting Zhang Xiangzheng Liao Zhaobo Chen Yongbo Wang Binshuang Pang Jinxiu Ma Xianchao Chen Jiangang Gao Changping Zhao Shiqing Gao 《International journal of molecular sciences》2022,23(15)
Temperature-sensitive genic male sterile (TGMS) line Beijing Sterility 366 (BS366) has been utilized in hybrid breeding for a long time, but the molecular mechanism underlying male sterility remains unclear. Expression arrays, small RNA, and degradome sequencing were used in this study to explore the potential role of miRNA in the cold-induced male sterility of BS366. Microspore observation showed defective cell plates in dyads and tetrads and shrunken microspores at the vacuolated stage. Differential regulation of Golgi vesicle transport, phragmoplast formation, sporopollenin biosynthesis, pollen exine formation, and lipid metabolism were observed between cold and control conditions. Pollen development was significantly represented in the 352 antagonistic miRNA-target pairs in the integrated analysis of miRNA and mRNA profiles. The specific cleavage of ARF17 and TIR1 by miR160 and miR393 were found in the cold-treated BS366 degradome, respectively. Thus, the cold-mediated miRNAs impaired cell plate formation through repression of Golgi vesicle transport and phragmoplast formation. The repressed expression of ARF17 and TIR1 impaired pollen exine formation. The results of this study will contribute to our understanding of the roles of miRNAs in male sterility in wheat. 相似文献