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Intelligent Wireless Communications Enabled by Cognitive Radio and Machine Learning

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China Communications 2018年第12期15卷 16-48页

作者： Xiangwei Zhou mingxuan sun Geoffrey Ye Li Biing-Hwang (Fred) Juang School of EECS Louisiana State University School of ECE Georgia Institute of Technology

The ability to intelligently utilize resources to meet the need of growing diversity in services and user behavior marks the future of wireless communication systems. Intelligent wireless communications aims at enabling the system to perceive and assess the available resources, to autonomously learn to adapt to the perceived wireless environment, and to reconfigure its operating mode to maximize the utility of the available resources. The perception capability and reconfigurability are the essential features of cognitive radio while modern machine learning techniques project great potential in system adaptation. In this paper, we discuss the development of the cognitive radio technology and machine learning techniques and emphasize their roles in improving spectrum and energy utility of wireless communication systems. We describe the state-of-the-art of relevant techniques, covering spectrum sensing and access approaches and powerful machine learning algorithms that enable spectrum and energy-efficient communications in dynamic wireless environments. We also present practical applications of these techniques and identify further research challenges in cognitive radio and machine learning as applied to the existing and future wireless communication systems.

关键词： cognitive radio energy efficiency machine learning reconfiguration spectrum efficiency

A New Species of Cupressinocladus from the Lower Cretaceous of Guyang Basin,Inner Mongolia,China and Cluster Analysis

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1200-1214页

作者： JIN Peihong MAO Teng DONG Junling WANG Zixi sun mingxuan XU Xiaohui DU Baoxia sun Bainian School of Earth Sciences & Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou University School of Electrical Engineering and Computer Science Louisiana State University

Cupressinocladus Seward is a fossil genus of conifers and conifer fossils with reproductive organs are very rare. In general, it is difficult to understand the natural affinities with other conifers. In this paper, a new species, Cupressinocladus guyangensis P.H. Jin et B.N. sun sp. nov., is reported based on branches with immature female cones from the Lower Cretaceous Guyang Formation of the Guyang Basin in Inner Mongolia, northern China. The foliage shoots are decussate. Leaves are decussate, imbricate, scale-like, weakly dimorphic, and bear longitudinal glands on the abaxial view. Stomata complexes are haplocheilic, monocyclic, irregularly arranged, and spread along the leaf margin. Immature female cones are subglobose with 6-8 cone scales, and three subglobose ovules arranged in a row at the base of the cone scales. Moreover, we performed cluster analysis using a statistics and machine learning toolbox for 23 fossils and extant species based on 16 morphological characters. The result implies that the new species bears a close resemblance to the extant Cupressusfunebris Endl. and might have nearest systematic affinities to it.

关键词： Cupressinocladus Immature female cone Lower Cretaceous Cluster analysis New species

Recent progress in organic electrodes for zinc-ion batteries

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Journal of Semiconductors 2020年第9期41卷 38-58页

作者： Shuaifei Xu mingxuan sun Qian Wang Chengliang Wang School of Optical and Electronic Information Wuhan National Laboratory for Optoelectronics(WNLO)Huazhong University of Science and TechnologyWuhan 430074China

Organic zinc-ion batteries(OZIBs)are emerging rechargeable energy storage devices and have attracted increasing attention as one of the promising alternatives of lithium-ion batteries,benefiting from the Zn metal(low cost,safety and small ionic size)and organic electrodes(flexibility,green and designable molecular structure).Organic electrodes have exhibited fine electrochemical performance in ZIBs,but the research is still in infancy and hampered by some ***,to provide insight into OZIBs,this review summarizes the progress of organic cathode materials for ZIBs and points out the existing challenges and then addresses potential *** is hoped that this review can stimulate the researchers to further develop high-performance OZIBs.

关键词： organic electrodes zinc-ion batteries redox compounds

非线性离散时间系统迭代学习控制的稳定性分析

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自动化学报 1998年第6期24卷 811-815页

作者：孙明轩西安工业学院电子工程系

讨论了初始偏移对于非线性离散时间系统迭代学习控制性能的影响．提出描述选择学习控制算法的学习律，并给出保证系统稳定性的充分条件．

关键词：稳定性迭代学习控制非线性离散时间系统

LMI_based robust iterative learning controller design for discrete linear uncertain systems

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控制理论与应用（英文版） 2005年第3期3卷 259-265页

作者： Jianming xu mingxuan sun Li YU College of Information Engineering Zhejiang University of Technology Hangzhou Zhejiang 310032 China

This paper addresses the design problem of robust iterative learning controllers for a class of linear discrete-time systems with norm-bounded parameter uncertainties. An iterative learning algorithm with current cycle feedback is proposed to achieve both robust convergence and robust stability. The synthesis problem of the proposed iterative learmng control （ILC） system is reformulated as a γ-suboptimal H-infinity control problem via the linear fractional transformation （LFT）. A sufficient condition for the convergence of the ILC algorithm is presented in terms of linear matrix inequalities （LMIs）. Furthermore, the linear wansfer operators of the ILC algorithm with high convergence speed are obtained by using existing convex optimization techniques. The simulation results demonstrate the effectiveness of the proposed method.

关键词： Iteradve learning control H-infinity control Linear fractional transformation Linear matrix inequality(LMI)

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注塑机注射速度的离散预期学习控制

机械工程学报 2007年第6期43卷 41-47页

作者：崔彩莲孙明轩浙江工业大学信息工程学院杭州310014

针对注塑成形过程的重复运行特性,采用离散预期学习控制方法对注射阶段的关键变量注射速度进行控制。针对离散化后的注塑机注射速度模型,根据收敛性条件以两步法设计预期学习控制中的两个参数——超前步长与学习增益,并与连续预期学习... 详细信息

针对注塑成形过程的重复运行特性,采用离散预期学习控制方法对注射阶段的关键变量注射速度进行控制。针对离散化后的注塑机注射速度模型,根据收敛性条件以两步法设计预期学习控制中的两个参数——超前步长与学习增益,并与连续预期学习控制作了比较。当收敛性条件不能在整个频段内满足时,利用DFT/IDFT截断可学习频段外的频率信号,保证跟踪误差单调收敛,并在离散频域内讨论测量噪声存在及初始定位不可重置时学习算法的跟踪性能。仿真结果表明,对于给定的期望注射速度曲线,该方法能得到比P型、D型迭代学习控制(ILC)更满意的跟踪性能,且具干扰抑制能力。

关键词：预期学习控制注塑机注射速度离散时间频域

A branched dihydrophenazine-based polymer as a cathode material to achieve dual-ion batteries with high energy and power density

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eScience 2021年第1期1卷 60-68页

作者： Shuaifei Xu Huichao Dai Shaolong Zhu Yanchao Wu mingxuan sun Yuan Chen Kun Fan Chenyang Zhang Chengliang Wang Wenping Hu School of Optical and Electronic Information Wuhan National Laboratory for Optoelectronics(WNLO)Huazhong University of Science and TechnologyWuhan 430074China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China

Organic electrode materials have exhibited good electrochemical performance in batteries,but their voltages and rate capabilities still require improvement to meet the increasing demand for batteries with high energy and power ***,we design and synthesize a branched dihydrophenazine-based polymer(p-TPPZ)as a cathode material for dual-ion batteries(DIBs)through delicate molecular *** with the linear dihydrophenazine-based polymer(p-DPPZ,with a theoretical capacity of 209 mAh g^(−1)),p-TPPZ possessed a higher theoretical capacity of 233 mAh g^(−1)and lower highest occupied molecular orbital energy levels,which resulted in a high actual capacity(169.3 mAh g^(−1)at 0.5 C),an average discharge voltage of 3.65 V(***+/Li)and a high energy density(618.2 Wh kg^(−1),based on the cathode materials).The branched structure of p-TPPZ led to a larger specific surface area than that of p-DPPZ,which was beneficial for the electrolyte infiltration and fast ionic transport,contributing to the high power *** to the fast reaction kinetics,even at a power density of 23,725 W kg^(−1)(40 C),the energy density still reached 474.5 Wh kg^(−1).We also made a detailed investigation of the p-TPPZ cathode’s charge storage *** work will stimulate the further molecular design to develop organic batteries with both high energy and power density.

关键词： Organic dual-ion batteries Branched polymers Dihydrophenazine-based polymers Organic cathodes Conjugated porous materials

一类Wiener非线性时变系统的迭代学习辨识

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电子与信息学报 2021年第9期43卷 2594-2600页

作者：仲国民孙明轩浙江工业大学信息工程学院杭州310023

针对Wiener非线性时变系统的参数辨识问题,该文提出一种基于重复轴的迭代学习算法来实现对时变甚至突变参数的估计。文中将维纳系统输出非线性部分的反函数进行多项式展开,进而构造了回归模型,未知参数及中间变量用其估计替代,分别给出... 详细信息

针对Wiener非线性时变系统的参数辨识问题,该文提出一种基于重复轴的迭代学习算法来实现对时变甚至突变参数的估计。文中将维纳系统输出非线性部分的反函数进行多项式展开,进而构造了回归模型,未知参数及中间变量用其估计替代,分别给出了采用迭代学习梯度算法和迭代学习最小二乘算法实现时变参数辨识的方法。仿真结果表明,与带遗忘因子的递推算法和迭代学习梯度算法相比,迭代学习最小二乘算法更具有参数估计收敛速度快,辨识精度高,系统输出误差小等优势,验证了所提学习算法的有效性。

关键词：时变参数 Wiener系统梯度算法最小二乘迭代学习

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有限时间迭代学习控制

系统科学与数学 2010年第6期30卷 733-741页

作者：孙明轩浙江工业大学信息工程学院杭州310023

针对任意初态情形,借助于初始修正吸引子的概念,讨论不确定时变系统能够达到实际完全跟踪性能的迭代学习控制方法.闭环系统中含有限时间控制作用,在预先指定的区间上实现零误差跟踪,且起始段的系统输出轨迹也可预先规划.分别讨论部分限... 详细信息

针对任意初态情形,借助于初始修正吸引子的概念,讨论不确定时变系统能够达到实际完全跟踪性能的迭代学习控制方法.闭环系统中含有限时间控制作用,在预先指定的区间上实现零误差跟踪,且起始段的系统输出轨迹也可预先规划.分别讨论部分限幅学习与完全限幅学习,证明闭环系统中各变量的一致有界性以及误差序列的一致收敛性.变量有界性证明得益于提出的限幅学习算法,特别是完全限幅学习算法可确保参数估值的变化范围.

关键词：迭代学习控制有限时间控制不确定时变系统