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951.
952.
非氧化物陶瓷-金属接合及其机理 总被引:2,自引:0,他引:2
综述了近年来非氧化物陶瓷-金属接合的发展动态,概括了活性合金法非氧化物陶瓷-金属的接合机理。 相似文献
953.
针对DTHS-A单片机实验平台的日常维护需要设计了该测试装置,该装置能够快速的检测实验电路中驱动芯片是否正常,与传统方法相比,节约了维护的时间,提高了检测效率.该装置以STC15F2K61S2为控制核心,通过按键与拨码开关来选择对应芯片,通过液晶显示与LED指示芯片是否正常,同时具有过流保护功能. 相似文献
954.
955.
针对三维不规则的点云格式和密度不均匀的问题,提出了一种融合多注意力机制与PointRCNN网络用于三维点云目标检测。本实验主要对PointRCNN两阶段网络分别进行改进,首先,把通道注意力与空间注意力机制串行通过调节输入到第一阶段各网络层的分布,批量归一化进一步快速识别三维特征;其次,引入交叉位置注意力机制到第二阶段网络为了避免交叉路径出现位置偏差,从而进一步精细化三维目标位置以进行特征提取。在KITTI数据集上实验结果表明:相比于PointRCNN检测网络,改进的网络在小汽车和行人测试上平均均值精度(mAP)分别提高了1.2%、1.9%。因此改进的方法在解决了点云格式不规则和密度不均匀问题的同时还保证了检测精度。 相似文献
956.
957.
Guo Tian Wenda Yang Xiao Song Dongfeng Zheng Luyong Zhang Chao Chen Peilian Li Hua Fan Junxiang Yao Deyang Chen Zhen Fan Zhipeng Hou Zhang Zhang Sujuan Wu Min Zeng Xingsen Gao Jun‐Ming Liu 《Advanced functional materials》2019,29(32)
Conductive ferroelectric domain walls—ultranarrow configurable conduction paths—have been considered as essential building blocks for future programmable domain wall electronics. For applications in high‐density devices, it is imperative to explore the conductive domain walls in small confined systems, while earlier investigations have hitherto focused on thin films or bulk single. Here, an observation and manipulation of conductive domain walls confined within small BiFeO3 nanoislands aligned in high‐density arrays are demonstrated. Using conductive atomic force microscopy, various types of conductive domain walls, including the head‐to‐head charged domain walls (CDWs), zigzag domain walls, and typical 71° head‐to‐tail neutral domain walls (NDWs), are distinctly visualized. The CDWs exhibit remarkably enhanced metallic conductivity with current of ≈nA order in magnitude and 104 times larger than that inside domains (0.01–0.1 pA), while the semiconducting NDWs allow much smaller current (≈10 pA) than the CDWs. The substantial difference in conductivity for dissimilar walls enables manipulations of various wall conduction states for individual addressable nanoislands via electrical tuning of domain structures. A controllable writing of four distinctive states in individual nanoislands can be achieved, showing application potentials for developing multilevel high‐density memories. 相似文献
958.
Ying Zhou Huaqiang Wu Bin Gao Wei Wu Yue Xi Peng Yao Shuanglin Zhang Qingtian Zhang He Qian 《Advanced functional materials》2019,29(30)
Associative memory is one of the significant characteristics of the biological brain. However, it has yet to be realized in a large memristor array due to the high requirements on the memristor device. In this work, the multilevel memristor cell is optimized by employing an electro‐thermal modulation layer. Memristor devices show both high resistance, cell‐to‐cell uniformity, and multilevel resistive switching behaviors with good reliability. A Hopfield neural network is experimentally demonstrated on a 1k memristor array that is capable of realizing the associative memory function for emotion image recovery. By using both asynchronous and synchronous refresh schemes, complete emotion images can be recalled from partial information. 相似文献
959.
Meili Li Qiuyu Shang Chun Li Shuai Li Yin Liang Wenjin Yu Cuncun Wu Liyun Zhao Yangguang Zhong Wenna Du Xianxin Wu Zhili Jia Yan Gao Hui Chen Xinfeng Liu Shaojun Guo Qing Liao Guichuan Xing Lixin Xiao Qing Zhang 《Advanced functional materials》2021,31(25):2102210
A solution-processed thin film made of all-inorganic CsPbBr3 perovskite is a promising candidate for low-cost and flexible green-color lasers. However, the amplified spontaneous emission (ASE) of solution-processed CsPbBr3 films still experiences a high threshold owing to poor morphology and insufficient optical gain. Here, a multiple-cation doping strategy is demonstrated to develop compact, smooth thin films of Cs0.87(FAMA)0.13PbBr3/(NMA)2PbBr4 (FA: formamidinium; MA: methylammonium; NMA: naphthylmethylammonium) with a record high net modal optical gain of ≈ 3030 cm−1 and low propagation loss of 1.0 cm−1. The FA and MA cations improve the crystallization kinetics to form continuous films, and the NMA cations reduce the grain dimension, increase film dispersibility/uniformity, and enhance spatial confinement to promote optical gain. Room-temperature ASE is demonstrated under a low threshold of ≈ 3.8 µ J cm−2 without degradation after four months of storage in glove box or excitation by 3 × 107 laser pulses. These findings provide insights into enhancing the optical gain and lowering the threshold of perovskite lasers in terms of molecular synthesis and microstructure engineering. 相似文献
960.
A BFSK and OOK IF base-band circuit is provided to implement the low-IF RF receivers for a dualband MICS/BCC network controller.In order to transfer the massive vital data immediately,the IF circuit is comprised of the fast-settling feed-forward programmable gain amplifier (PGA),a Gm-C complex filter,the fixed gain amplifier (FGA) and a 4-input quadratic sum demodulator.A novel auto-switched coarse gain-setting method is adopted in the PGA to enhance the reaction speed and narrow the output signal range.Also the PGA does not suffer the same stability constraint as open-loop topologies.The complex filter fulfills the function of image rejection,in which the center frequency and bandwidth can be adjusted individually.The FGA is used to ameliorate the linearity and the 'quadratic sum' demodulator can reduce the overall power consumption.The designed IF circuit is fabricated with SMIC 0.18/μm CMOS process.The chip area is about 5.36 mm2.Measurement results are given to verify the design goals. 相似文献