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951.
952.
运营商4G/5G网络共用2.6 GHz频段,随着5G基站入网,同频干扰问题随之出现.本文提出了一种可进行同频干扰智能预判的系统,该系统可在频点调整前进行同频干扰的风险预判,以便于及时规避风险,研究分析和测试验证表明,该系统的输出结果有助于同频干扰小区的识别,快速判定同频干扰风险小区,提升优化效率,确保用户感知. 相似文献
953.
Shuiying Xiang Yanan Han Ziwei Song Xingxing Guo Yahui Zhang Zhenxing Ren Suhong Wang Yuanting Ma Weiwen Zou Bowen Ma Shaofu Xu Jianji Dong Hailong Zhou Quansheng Ren Tao Deng Yan Liu Genquan Han Yue Hao 《半导体学报》2021,42(2):66-82
The explosive growth of data and information has motivated various emerging non-von Neumann computational approaches in the More-than-Moore era.Photonics neuromorphic computing has attracted lots of attention due to the fascinating advantages such as high speed,wide bandwidth,and massive parallelism.Here,we offer a review on the optical neural computing in our research groups at the device and system levels.The photonics neuron and photonics synapse plasticity are presented.In addition,we introduce several optical neural computing architectures and algorithms including photonic spiking neural network,photonic convolutional neural network,photonic matrix computation,photonic reservoir computing,and photonic reinforcement learning.Finally,we summarize the major challenges faced by photonic neuromorphic computing,and propose promising solutions and perspectives. 相似文献
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955.
Kwon-Hyeon Kim Paul H. Dannenberg Hao Yan Sangyeon Cho Seok-Hyun Yun 《Advanced functional materials》2021,31(48):2103413
Fluorescent microbeads are widely used for applications in life sciences and medical diagnosis. The spectral contrast and sharpness of photoluminescence are critical in the utilities of microbeads for imaging and multiplexing. Here, microbeads capable of generating single-peak laser emission with a sub-nanometer linewidth are demonstrated. The microbeads are made of quantum dots that are tightly packed and crosslinked via ligand exchange for high optical gain and refractive index as well as material stability. Bright single-mode lasing with no photobleaching is achieved with particle diameters as small as 1.5 µm in the air. Sub-nm lasing emission is maintained even inside high-index surroundings, such as organic solvents and biological tissues. Feasibility of intracellular tagging and multi-color imaging in vivo is demonstrated. 相似文献
956.
Jiefeng Hai Hao Wu Xinxing Yin Jiaxing Song Lin Hu Yingzhi Jin Ling Li Zhen Su Zhiguang Xu Hao Wang Zaifang Li 《Advanced functional materials》2021,31(51):2105458
Hole transport materials (HTMs) play a significant role in device efficiencies and long-term stabilities of perovskite solar cells (PSCs). In this work, two simple dopant-free HTMs are designed with a large conjugated electron-deficient core. On the one hand, a large coplanar backbone endows enhanced π–π stacking and reduced hole hopping distance. On the other hand, the incorporation of electron-deficient unit can easily tune the energy levels as well as increase hole mobilities. Combining these two advantages together, 12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro[1,2,5]thiadiazole[3,4-e]thieno[2″,3″:4,5]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole is chosen as the large electron-deficient core to construct two novel dopant-free HTMs, Y6-T and Y-T. Both Y6-T and Y-T behave suitable highest occupied molecular orbital levels, good hole mobilities, as well as strong hydrophobicities. After careful device optimization with a passivation agent, Y-T delivers an impressive power conversion efficiency of 20.29%, which is higher than that of Y6-T (18.82%) and doped spiro-OMeTAD (19.24%). Moreover, PSCs based on Y6-T and Y-T show much better long-term stabilities than spiro-OMeTAD due to the intrinsic hydrophobicity. Therefore, this work provides a promising candidate as well as a useful design strategy for exploring dopant-free HTMs, which may pave the way for the commercialization of PSCs. 相似文献
957.
A CMOS analog equalizer is designed to meet the different high speed communication specifications,such as USB 2.0,PCI-E and rapid IO.The proposed circuit architecture could facilitate the wide frequency scale ranging from 1 to 3.125 Gbps by adjusting the locations of pole and zero,so that the circuit can change its response accordingly as the channel characteristic alters.In order to balance the parasitic capacitors in the internal point,symmetric switches are addressed to generate the equal load for dif... 相似文献
958.
959.
In this paper, a Distributed In-Memory Database (DIMDB) system is proposed to improve processing efficiency in mass data applications. The system uses an enhanced language similar to Structured Query Language (SQL) with a key-value storage schema. The design goals of the DIMDB system is described and its system architecture is discussed. Operation flow and the enhanced SQL-like language are also discussed, and experimental results are used to test the validity of the system. 相似文献
960.