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51.
A novel torsion sensor is proposed, which is composed of one long period fibre grating and one asymmetrically corrugated long period fibre grating based on the high-frequency CO2 laser pulses technology and burning fibre coating and etching cladding technology, respectively. By combing the advantages of the two aforementioned elements, a sensitivity of 331.7 and 310.3 pm/(rad/m) towards clockwise and anticlockwise direction, respectively, is reached in the experiments. 相似文献
52.
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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54.
Laura Mannarino Lara Paracchini Federica Pezzuto Gheorghe Emilian Olteanu Laura Moracci Luca Vedovelli Irene De Simone Cristina Bosetti Monica Lupi Rosy Amodeo Alessia Inglesi Maurizio Callari Serena Penpa Roberta Libener Sara Delfanti Antonina De Angelis Alberto Muzio Paolo Andrea Zucali Paola Allavena Giovanni Luca Ceresoli Sergio Marchini Fiorella Calabrese Maurizio DIncalci Federica Grosso 《International journal of molecular sciences》2022,23(10)
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56.
准确预测风电功率对于提高电力系统的效率和安全性具有重要意义, 而风能的间歇性和随机性特点导致风电功率难以准确预测. 因此, 提出一种改进Informer的风电功率预测模型PCI-Informer (PATCH-CNN-IRFFN-Informer). 将序列数据划分为子序列级补丁, 并进行特征提取和整合, 提高模型对序列数据的处理能力和效果; 采用多尺度因果卷积自注意力机制, 实现多尺度局部特征融合, 提高模型对局部信息的理解和建模能力; 引入反向残差前馈网络 (IRFFN), 增强模型对局部结构信息的提取和保留能力. 某风电场数据实验结果表明, 与主流预测模型相比, PCI-Informer模型在不同预测步长下均取得了更好的预测效果, 在MAE指标上相比Informer模型平均降低了11.1%, 有效提高了短期风电功率的预测精度. 相似文献
57.
Lucas Taoro-Gonzlez Daniel Pereda Catalina Valds-Baizabal Miriam Gonzlez-Gmez Jos A. Prez Ftima Mesa-Herrera Ana Canerina-Amaro Herminia Prez-Gonzlez Covadonga Rodríguez Mario Díaz Raquel Marin 《International journal of molecular sciences》2022,23(13)
Long-chain polyunsaturated fatty acids (LCPUFA), essential molecules whose precursors must be dietary supplied, are highly represented in the brain contributing to numerous neuronal processes. Recent findings have demonstrated that LCPUFA are represented in lipid raft microstructures, where they favor molecular interactions of signaling complexes underlying neuronal functionality. During aging, the brain lipid composition changes affecting the lipid rafts’ integrity and protein signaling, which may induce memory detriment. We investigated the effect of a n-3 LCPUFA-enriched diet on the cognitive function of 6- and 15-months-old female mice. Likewise, we explored the impact of dietary n-3 LCPUFAs on hippocampal lipid rafts, and their potential correlation with aging-induced neuroinflammation. Our results demonstrate that n-3 LCPUFA supplementation improves spatial and recognition memory and restores the expression of glutamate and estrogen receptors in the hippocampal lipid rafts of aged mice to similar profiles than young ones. Additionally, the n-3 LCPUFA-enriched diet stabilized the lipid composition of the old mice’s hippocampal lipid rafts to the levels of young ones and reduced the aged-induced neuroinflammatory markers. Hence, we propose that n-3 LCPUFA supplementation leads to beneficial cognitive performance by “rejuvenating” the lipid raft microenvironment that stabilizes the integrity and interactions of memory protein players embedded in these microdomains. 相似文献
58.
A first order Markov model of program behaviour is developed from FORTRAN program instruction data. The program model is evaluated by using it to generate page references for input into a simple virtual memory operating system (VMOS) simulation model. The actual trace data are also used to drive the VMOS model. In both cases the fault probability is obtained for different replacement rules, memory sizes and page sizes. A comparison of fault probabilities is used to determine the effectiveness of the Markov program model. 相似文献
59.
Driven by data-intensive applications, flash-based solid state drives (SSDs) have become increasingly popular in enterprise-scale storage systems. Flash memory exhibits inherent parallelism. However, existing solid state drives have not fully exploited this superiority. We propose P3Stor, a parallel solid state storage architecture that makes full use of flash memory by utilizing module- and bus-level parallelisms to increase average bandwidth and employing chip-level interleaving to hide I/O latency. To im... 相似文献
60.
缓冲区溢出等内存错误漏洞的产生往往来自对内存拷贝类函数的不当使用. 对二进制程序中的内存拷贝类函数进行识别有利于发现内存错误漏洞. 目前针对二进制程序中内存拷贝类函数的识别方法主要借助静态分析来提取函数的特征、控制流、数据流等信息进行识别, 具有较高的误报率和漏报率. 为了提高对内存拷贝类函数识别的效果, 提出一种基于静态和动态混合分析的技术CPSeeker. 所提方法结合静态分析和动态分析各自的优势, 分阶段对函数的全局静态信息和局部执行信息进行搜集, 对提取到的信息进行融合分析, 进而识别二进制程序中的内存拷贝类函数. 实验结果表明, 尽管CPSeeker在运行时间上有所增加, 但在内存拷贝类函数识别的效果上, 其F1值达到了0.96, 远优于最新的工作BootStomp、SaTC、CPYFinder以及Gemini, 并且不受编译环境(编译器版本、编译器种类、编译器优化等级)的影响. 此外, CPSeeker在真实的固件测试中也有更好的表现. 相似文献