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Neural Regeneration Research 2011年第4期6卷 304-308页

作者： Yonghong yang Chengqi he lin yang Qiang Gao Shasha Li Jing he Department of Rehabilitation Medicine West China Hospital Sichuan University Key Laboratory of Rehabilitation Medicine of SichuanProvince Chengdu 610041 Sichuan Province China

Low-frequency electrical stimulation has resulted in favorable effects in the treatment of post-stroke dysphagia. However, the safety of cervical low-frequency electrical stimulation remains unclear because of numerous nerves and blood vessels in the neck. In the present study, rats with ischemic stroke underwent low-frequency electrical stimulation, and systemic and local effects of electrical stimulation at different densities and waveforms were investigated. Electrical stimulation resulted in no significant effects on body mass, liver or kidney function, or mortality rate. In addition, no significant adverse reaction was observed, despite overly high intensity of low-frequency electrical stimulation, which induced laryngismus, results from the present study suggested that it is safe to stimulate the neck with a low-frequency electricity under certain intensities.

关键词： adverse reaction deglutition rehabilitation low-frequency electrical stimulation ischemic stroke: rats

EM Scattering from Conducting Flat Plates Coated with Thin RAM

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Wuhan University Journal of Natural Sciences 2002年第2期7卷 185-188页

作者： yang he-lin Xia Ying-qing Lu Shu Liu Wu Department of Physics Central China Normal UniversityWuhan 430079China School of Electronic Information Wuhan UniversityWuhan 430072China

According to the equivalence principles, high frequency approximation and boundary conditions, a method has been developed to deal with the EM scattering by a rectangular conducting flat plate coated with uniaxial anisotropic radar absorbing material (RAM). The simple and effective method is available to the system of RCS prediction in which the large complex targets modeled by facets and wedges. Numerical results show some properties of EM scattering by conducting plate coated with thin uniaxial anisotropic RAM.

关键词： EM scattering equivalence principles radar absorbing material

Research on the Electromagnetic Scattering Near the Field

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Wuhan University Journal of Natural Sciences 2002年第2期7卷 182-184页

作者： Xia Ying-qing yang he-lin Xu Peng-gen Liu wu Department of Physics Central China Normal UniversityWuhan 430079China School of Electronic Information Wuhan UniversityWuhan 430072China

We calculate and analyze the scattering near the field from some simple and complex targets using the method of picture elements (PEL), based upon the method of high-frequency approximation. It introduces the critical distance of the near field and the far field which is related with the dimension of the target. The problem of the EMS near field from large size objects can be transformed to the problem of the far field by parting it to many very small size elements. By calculating the EMS near fields of some simple and complex targets based on the SCTE (scattering from complex targets and environments) system, the results show that there are much difference between the near field and the far field. And the characteristics of the near field are more complicated. This work has practical engineering value in the area of the electromagnetic compatibility (EMC), electromagnetic interference (EMI) prediction and electromagnetic scattering (EMS).

关键词： electromagnetic scattering vector scattering function method of picture elements

Fast removal of ocular artifacts from electroencephalogram signals using spatial constraint independent component analysis based recursive least squares in brain-computer interface

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Frontiers of Information Technology & Electronic Engineering 2015年第6期16卷 486-496页

作者： Bang-hua yang Liang-fei he lin lin Qian WANG Shanghai Key Laboratory of Power Station Automation Technology Department of AutomationSchool of Mechatronic Engineering and Automation Shanghai University Shanghai 200072 China

Ocular artifacts cause the main interfering signals within electroencephalogram （EEG） signal measurements. An adaptive filter based on reference signals from an electrooculogram （EOG） can reduce ocular interference, but collecting EOG signals during a long-term EEG recording is inconvenient and uncomfortable for the subject. To remove ocular artifacts from EEG in brain-computer interfaces （BCIs）, a method named spatial constraint independent component analysis based recursive least squares （SCICA-RLS） is proposed. The method consists of two stages. In the first stage, independent component analysis （ICA） is used to decompose multiple EEG channels into an equal number of independent components （ICs）. Ocular ICs are identified by an automatic artifact detection method based on kurtosis. Then empirical mode decomposition （EMD） is employed to remove any cerebral activity from the identified ocular ICs to obtain exact altifact ICs. In the second stage, first, SCICA applies exact artifact ICs obtained in the first stage as a constraint to extract artifact ICs from the given EEG signal. These extracted ICs are called spatial constraint ICs （SC-ICs）. Then the RLS based adaptive filter uses SC-ICs as reference signals to reduce interference, which avoids the need for parallel EOG recordings. In addition, the proposed method has the ability of fast computation as it is not necessary for SCICA to identify all ICs like ICA. Based on the EEG data recorded from seven subjects, the new approach can lead to average classification accuracies of 3.3% and 12.6% higher than those of the standard ICA and raw EEG, respectively. In addition, the proposed method has 83.5% and 83.8% reduction in time-consumption compared with the standard ICA and ICA-RLS, respectively, which demonstrates a better and faster OA reduction.

关键词： Ocular artifacts Electroencephalogram (EEG) Electrooculogram (EOG) Brain-computer interface (BCI) Spatialconstraint independent component analysis based recursive least squares (SCICA-RLS)

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu lin he lin-Sen Ye Xiao-Feng yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng he Fan yang Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

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双向多频超材料吸波器的设计与实验研究

物理学报 2013年第17期62卷 195-200页

作者：韩松杨河林华中师范大学物理科学与技术学院武汉430079

利用金属线单元组合法,仿真设计并制作了一种在通信频段(0.8—3 GHz)的双向多频超材料吸波器.仿真与实验结果表明:该吸波器对于不同极化和宽角度入射的电磁波有三个稳定的吸波频点,分布在2.04 GHz,2.34 GHz和2.65 GHz,吸收率分别达到92.... 详细信息

利用金属线单元组合法,仿真设计并制作了一种在通信频段(0.8—3 GHz)的双向多频超材料吸波器.仿真与实验结果表明:该吸波器对于不同极化和宽角度入射的电磁波有三个稳定的吸波频点,分布在2.04 GHz,2.34 GHz和2.65 GHz,吸收率分别达到92.3%,95.3%和94.7%.该吸波器设计简单、灵活性强、吸收效果好、易于加工,为通信领域的电磁屏蔽或抗电磁干扰提供了新的方法.

关键词：超材料双向多频吸收极化不敏感宽角度入射

Joint Estimation of SOH and RUL for Lithium-Ion Batteries Based on Improved Twin Support Vector Machineh

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Energy Engineering 2025年第1期122卷 243-264页

作者： Liyao yang HongyanMa Yingda Zhang Wei he School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China Institute of Distributed Energy Storage Safety Big Data Beijing100044China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing100044China

Accurately estimating the State of health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management ***,due to the complex internal chemical systems of LIBs and the nonlinear degradation of their performance,direct measurement of SOH and RUL is *** address these issues,the Twin Support Vector Machine(TWSVM)method is proposed to predict SOH and ***,the constant current charging time of the lithium battery is extracted as a health indicator(HI),decomposed using Variational Modal Decomposition(VMD),and feature correlations are computed using Importance of Random Forest Features(RF)to maximize the extraction of critical factors influencing battery performance ***,to enhance the global search capability of the Convolution Optimization Algorithm(COA),improvements are made using Good Point Set theory and the Differential Evolution *** Improved Convolution Optimization Algorithm(ICOA)is employed to optimize TWSVM parameters for constructing SOH and RUL prediction ***,the proposed models are validated using NASA and CALCE lithium-ion battery *** results demonstrate that the proposed models achieve an RMSE not exceeding 0.007 and an MAPE not exceeding 0.0082 for SOH and RUL prediction,with a relative error in RUL prediction within the range of[-1.8%,2%].Compared to other models,the proposed model not only exhibits superior fitting capability but also demonstrates robust performance.

关键词： State of health remaining useful life variational modal decomposition random forest twin support vector machine convolutional optimization algorithm

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基于全介质超表面的电磁诱导透明研究

光子学报 2018年第11期47卷 211-219页

作者：胡森刘丹杨河林湖北第二师范学院物理与机电工程学院武汉430205 华中师范大学物理科学与技术学院武汉430079

设计了一种基于TiO2介质的全介质电磁诱导透明超表面模型,该结构由两根十字垂直交叉的介质棒和四个介质方块组成.在入射电磁场的作用下,介质棒中直接被入射电磁场激励的米氏电谐振通过相互耦合作用激发了介质方块中的磁共振,并产生谐振... 详细信息

设计了一种基于TiO2介质的全介质电磁诱导透明超表面模型,该结构由两根十字垂直交叉的介质棒和四个介质方块组成.在入射电磁场的作用下,介质棒中直接被入射电磁场激励的米氏电谐振通过相互耦合作用激发了介质方块中的磁共振,并产生谐振模之间的相消干涉,从而产生了类电磁诱导透明现象.利用电磁仿真软件和双谐振子耦合模理论,模拟计算和定量分析了类电磁诱导透明效应,结果表明:在电磁波正入射下,该结构在0.552THz处产生一透射率接近96%的透明窗口.由于其结构单元具有4度旋转对称性和多个暗模谐振元素,使得诱导透明效应出现较宽频带且呈现出对入射电场极化方向不敏感的特性.

关键词：超表面电磁诱导透明仿真全介质米共振极化不敏感

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从东晋玄言诗看佛、玄之际

湖南师范大学社会科学学报 2006年第5期35卷 113-118页

作者：杨合林湖南师范大学文学院湖南长沙410081

佛、玄之间的交争与融合构成了东晋文化思想的基本特点,这从当日名僧与名士的玄言诗创作中亦可得到印证。较能反映东晋佛、玄之际的玄言诗创作主要有:支遁的以玄释佛;康僧渊和张翼的佛、玄之争;慧远的净化佛学。通过对这些作品的解析,... 详细信息

佛、玄之间的交争与融合构成了东晋文化思想的基本特点,这从当日名僧与名士的玄言诗创作中亦可得到印证。较能反映东晋佛、玄之际的玄言诗创作主要有:支遁的以玄释佛;康僧渊和张翼的佛、玄之争;慧远的净化佛学。通过对这些作品的解析,可对当日士人信念之实际和社会文化思想演进之归向得一亲切深入之感受和解会。

关键词：玄言诗佛学玄学