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以仅能获取角度信息的全捷联导引头为研究对象,针对采用直接微分提取惯性视线角速率时存在的噪声放大问题,基于跟踪微分器设计了一种全捷联制导信息提取算法。结合导引头的性能指标要求,对3种不同形式跟踪微分器的提取效果进行了对比分析。仿真结果表明,采用非线性微分器进行惯性视线角速率提取,可以减小延迟时间,避免噪声放大,有效提高制导精度,具有一定的工程应用价值。 相似文献
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Molecular imaging, as an emerging technique in current medical diagnostics, therapy and biology science, has received more and more attention in academia, industry, as well as medical practices. And the applications of nanotechnology in this field stimulate its development. This paper explores the development of the basic research and applied research on nano-enhanced molecular imaging, and does the in-depth analysis by adopting the bibliometrics method. The results show that the US is the leader in this field, who has the absolute advantages. Germany, UK and France and Japan are the followed ones. The rapidly developing Asian countries , China and South Korea might become the potential competitors. Research network analysis draws the conclusion that the other countries and regions share the same research interests with the US. The US not only take the lead in the researching number, but also directing the future orientation of this field. However, the US has not much international collaboration. The collaboration within the country and regions show that collaboration in this field is limited to the regional adjacency. Disciplinary analysis reveals that the major subjects which relate intimately to the nano-enhanced molecular imaging are chemistry, biomedical science and material science. 相似文献
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Ziyang Zhang Tianran Li Yujie Wu Yinjun Jia Congwei Tan Xintong Xu Guanrui Wang Juan Lv Wei Zhang Yuhan He Jing Pei Cheng Ma Guoqi Li Haizheng Xu Luping Shi Hailin Peng Huanglong Li 《Advanced materials (Deerfield Beach, Fla.)》2019,31(3)
Concomitance of diverse synaptic plasticity across different timescales produces complex cognitive processes. To achieve comparable cognitive complexity in memristive neuromorphic systems, devices that are capable of emulating short‐term (STP) and long‐term plasticity (LTP) concomitantly are essential. In existing memristors, however, STP and LTP can only be induced selectively because of the inability to be decoupled using different loci and mechanisms. In this work, the first demonstration of truly concomitant STP and LTP is reported in a three‐terminal memristor that uses independent physical phenomena to represent each form of plasticity. The emerging layered material Bi2O2Se is used for memristors for the first time, opening up the prospects for ultrathin, high‐speed, and low‐power neuromorphic devices. The concerted action of STP and LTP allows full‐range modulation of the transient synaptic efficacy, from depression to facilitation, by stimulus frequency or intensity, providing a versatile device platform for neuromorphic function implementation. A heuristic recurrent neural circuitry model is developed to simulate the intricate “sleep–wake cycle autoregulation” process, in which the concomitance of STP and LTP is posited as a key factor in enabling this neural homeostasis. This work sheds new light on the development of generic memristor platforms for highly dynamic neuromorphic computing. 相似文献
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采用离子束溅射镀膜装置制备了一种新的材料组合Si/C多层膜 ,用于 30 4nm波段的正入射多层膜反射镜。并用软X射线反射率计测得其反射比最大值为 0 14。有效地抑制了 15 0nm处的二级衍射峰。 相似文献
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Die Su Yi Pei Li Liu Zhixiao Liu Junfang Liu Min Yang Jiaxing Wen Jing Dai Huiqiu Deng Guozhong Cao 《纳微快报(英文)》2021,(7):91-104
Wearable and portable mobile phones play a critical role in the market,and one of the key technologies is the flexible electrode with high spe-cific capacity an... 相似文献
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