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The charge storage characteristics of P-channel Ge/Si hetero-nanocrystal based MOSFET memory has been investigated and a logical array has been constructed using this memory cell. In the case of the thickness of tunneling oxide T_ox=2nm and the dimensions of Si- and Ge-nanocrystal D_Si=D_Ge=5nm, the retention time of this device can reach ten years(~1×10~8s) while the programming and erasing time achieve the orders of microsecond and millisecond at the control gate voltage |V_g|=3V with respect to N-wells, respectively. Therefore, this novel device, as an excellent nonvolatile memory operating at room temperature, is desired to obtain application in future VLSI. 相似文献
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运用神经网络对氧气顶吹转炉自动化进行动态预报[韩国]S.Y.Yun等1前言在氧气顶吹转炉工艺中,决定操作成功与否的关键是钢水温度和杂质量的控制,因而,要对其进行动态控制。本文介绍一种新的数学方法即以神经网络为基础建立的用于氧气顶吹转炉工艺控制的新型动... 相似文献
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Efficiently performing high-resolution direction of arrival (DOA) estimation under low signal-to-noise ratio (SNR) conditions has always been a challenge task in the literatures. Obvi-ously, in order to address this problem, the key is how to mine or reveal as much DOA related in-formation as possible from the degraded array outputs. However, it is certain that there is no per-fect solution for low SNR DOA estimation designed in the way of winner-takes-all. Therefore, this paper proposes to explore in depth the complementary DOA related information that exists in spa-tial spectrums acquired by different basic DOA estimators. Specifically, these basic spatial spec-trums are employed as the input of multi-source information fusion model. And the multi-source in-formation fusion model is composed of three heterogeneous meta learning machines, namely neural networks (NN), support vector machine (SVM), and random forests (RF). The final meta-spec-trum can be obtained by performing a final decision-making method. Experimental results illus-trate that the proposed information fusion based DOA estimation method can really make full use of the complementary information in the spatial spectrums obtained by different basic DOA estim-ators. Even under low SNR conditions, promising DOA estimation performance can be achieved. 相似文献
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Shui-Jing Tang Paul H.Dannenberg Andreas C.Liapis Nicola Martino Yue Zhuo Yun-Feng Xiao Seok-Hyun Yun 《光:科学与应用(英文版)》2021,10(2):197-207
The ability to track individual cells in space over time is crucial to analyzing heterogeneous cell populations.Recently,microlaser particles have emerged as unique optical probes for massively multiplexed single-cell tagging.However,the microlaser far-field emission is inherently direction-dependent,which causes strong intensity fluctuations when the orientation of the particle varies randomly inside cells.Here,we demonstrate a general solution based on the incorporation of nanoscale light scatterers into microlasers.Two schemes are developed by introducing either boundary defects or a scattering layer into microdisk lasers.The resulting laser output is omnidirectional,with the minimum-to-maximum ratio of the angle-dependent intensity improving from 0.007(-24 dB)to>0.23(-6dB).After transfer into live cells in vitro,the omnidirectional laser particles within moving cells could be tracked continuously with high signal-to-noise ratios for 2 h,while conventional microlasers exhibited frequent signal loss causing tracking failure. 相似文献
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<正> 随着改革开放的进一步深入,本世纪未的最后十年成了中国发展关键的十年。1981年2月20日,中共中央、国务院作出了《关天加强职工教育工作的决定》明确指出“职工培训是开发智力、培养人才的重要途径,是持续发展国民经济的重要保证”。同时,党的十三大报告指出“从根本上说,科技的发展,经济的振兴,乃至整个社会的进步,都取决于劳动者素质的提高和大量合格人才的培养”。尤其是在今天这个科学技术迅猛发展的社会,以及我们面临恢复 相似文献