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61.
In this study,by changing both pier diameters and particle sizes of sand bed in flume experiments,the scour process around cylindrical bridge piers under an ice... 相似文献
62.
Yinian Feng Bo Zhang Chen Zhi Ke Liu Weilong Liu Fang Shen Chuanqi Qiao Jicong Zhang Yong Fan Xiaobo Yang 《中国通信》2021,(5):210-220
With the successful demonstration of terahertz (THz) high-speed wireless data transmission,the THz frequencies are now becoming a worth candidate for post-5G wi... 相似文献
63.
64.
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
65.
As an effective supplement to traditional security solutions, reputation mechanism, which can encourage cooperation among individual entities and minimize the damage mainly resulted from insider attacks, has received much concern by the research community. In this article, a negative multinomial reputation model for self-organized networks is proposed. Compared with binary parameter based binomial reputation model, our model is featured with multiple parameters which can depict objective facts more precisely and accurately. Moreover, free from fixed increment on parameters in binomial model, the increment in our model can be 2 or more, which makes our model flexible and suitable for more practical applications such as networks with sleep mechanisms. Through three metrics of measurement, i.e. convergence time to detecting malicious entities, success rate of malicious entities, and success rate of benign entities, our model shows a better performance in the simulations and excels in these three aspects. 相似文献
66.
依据国家标准可以检测冰箱在平稳运行状态下的噪声水平,同时利用傅立叶变换可对冰箱噪声进行分析,并得到关键频率。但对于一些异常噪声,非稳态信号,傅立叶变换只能得到大概规律,不能得到细节信息,这时可利用时域分析方法进行补充,利用时域分析中小波变化的"自适应变化"时频窗得到噪声细节,并加以处理得到更多频率信息,为后期改善提出意见。 相似文献
67.
68.
Zicheng Li Yifeng Gao Zhihao Zhang Qiu Xiong Longhui Deng Xiaochun Li Qin Zhou Yuanxing Fang Peng Gao 《纳微快报(英文)》2021,(7):12-27
Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but... 相似文献
69.
Rapid global population growth has caused an increasing need for products containing protein.Meat products are the most common high-protein food source,but impa... 相似文献
70.