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A Kind of Algorithm on B-Spline Wavelet-BEM

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 265-268页

作者： Cheng Yong-jun Yi Xu-ming Ye Bi-quan shen yuan-tong College of Mathematical and Computer Sciences Wuhan University Wuhan China Department of Mathematics and Physics China University of Geosciences Wuhan China

B-Spline wavelet-BEM numerical algorithm is presented. To avoid to treating singular integrals in wavelet-BEM, a method of putting source points out of the domain is used and discussed. Meanwhile, two higher effective numerical quadrature formulae are suggested. Finally, an example in mechanics is given and numerical results show that this method is effective. In addition, this method can be extended to manipulate problems, especially, with singularity.

关键词： Key words B Spline wavelet BEM numerical quadrature

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断裂分析的小波数值方法

应用数学和力学 2000年第10期21卷 1028-1032页

作者：沈远彤羿旭明中国地质大学数理系武汉430074 武汉大学数学与计算机科学学院武汉430072

利用小波具有的良好局部化特性 ,用小波函数对位移场进行逼近 ,建立了小波数值计算格式 ,模拟了裂纹尖端的奇异性问题·　算例求出了裂纹尖端的应力强度因子。

关键词：小波数值计算格式尺度函数应力强度因子断裂力学断裂分析

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： tongyue Li Ziliang Xie Wenjiao Zhou Huan tong Dawen Yang Anjia Zhang yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

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基于小波包变换的威格纳分布交叉项的抑制

湖北大学学报（自然科学版） 2006年第1期28卷 4-6,11页

作者：陈洁沈远彤中国地质大学数理学院湖北武汉430074

威格纳分布是一种重要的时频分析方法,但交叉干扰问题影响了它的推广应用.基于小波包分析,利用小波包对信号的威格纳时频分布进行分解,并利用分解系数重构时频图,使交叉项得到抑制和改善,实验结果表明此方法简单有效.

关键词：时频分布交叉项小波包

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基于特征聚类的稀疏自编码快速算法

电子学报 2018年第5期46卷 1041-1046页

作者：付晓沈远彤付丽华杨迪威中国地质大学数学与物理学院湖北武汉430074

稀疏自编码网络在自然语言、图像处理等领域都取得了显著效果.已有的研究表明增加网络提取的特征个数可以优化稀疏自编码网络的处理效果,同时该操作将导致网络训练耗时过长.为尽可能减少网络的训练时间,本文提出了一种基于特征聚类的稀... 详细信息

稀疏自编码网络在自然语言、图像处理等领域都取得了显著效果.已有的研究表明增加网络提取的特征个数可以优化稀疏自编码网络的处理效果,同时该操作将导致网络训练耗时过长.为尽可能减少网络的训练时间,本文提出了一种基于特征聚类的稀疏自编码快速算法.本算法首先根据K均值聚类最优数确定本质特征的个数,再由网络训练得到本质特征,并通过旋转扭曲增加特征的多样性,使网络处理效果得到提升的同时,减少网络训练耗间.实验在标准的手写体识别数据库MNIST和人脸数据库CMU-PIE上进行,结果表明本文所提算法能在保证网络正确率有所提升的同时,大幅度缩短网络训练耗时.

关键词：深度学习稀疏自编码器特征提取 K均值聚类

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基于半监督编码生成对抗网络的图像分类模型

自动化学报 2020年第3期46卷 531-539页

作者：付晓沈远彤李宏伟程晓梅中国地质大学数学与物理学院武汉430074

在实际应用中,为分类模型提供大量的人工标签越来越困难,因此,近几年基于半监督的图像分类问题获得了越来越多的关注.而大量实验表明,在生成对抗网络(Generative adversarial network,GANs)的训练过程中,引入少量的标签数据能获得更好... 详细信息

在实际应用中,为分类模型提供大量的人工标签越来越困难,因此,近几年基于半监督的图像分类问题获得了越来越多的关注.而大量实验表明,在生成对抗网络(Generative adversarial network,GANs)的训练过程中,引入少量的标签数据能获得更好的分类效果,但在该类模型的框架中并没有考虑用于提取图像特征的结构,为了进一步利用其模型的学习能力,本文提出一种新的半监督分类模型.该模型在原生成对抗网络模型中添加了一个编码器结构,用于直接提取图像特征,并构造了一种新的半监督训练方式,获得了突出的分类效果.本模型分别在标准的手写体识别数据库MNIST、街牌号数据库SVHN和自然图像数据库CIFAR-10上完成了数值实验,并与其他半监督模型进行了对比,结果表明本文所提模型在使用少量带标数据情况下得到了更高的分类精度.

关键词：深度学习生成对抗网络图像分类半监督学习

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng tong-Qi yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

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一种基于视觉特性的图像质量评价指标

信号处理 2011年第11期27卷 1691-1695页

作者：杨迪威沈远彤李宏伟熊超沈永珞中国地质大学数理学院武汉430074 中国地质大学机电学院武汉430074

在分析多通道结构、遮掩效应、敏感度带通特性等人类基本视觉系统特性(HVS)的基础上,提出了一种新的图像质量评价指标的构造方法。指标构造先借助多尺度几何分析(MGA)中的Contourlet变换对图像进行子带分解以此模拟视觉多通道结构特性,... 详细信息

在分析多通道结构、遮掩效应、敏感度带通特性等人类基本视觉系统特性(HVS)的基础上,提出了一种新的图像质量评价指标的构造方法。指标构造先借助多尺度几何分析(MGA)中的Contourlet变换对图像进行子带分解以此模拟视觉多通道结构特性,然后在各子带中使用一种视觉遮掩效应模型获取失真图像和参考图像之间的视觉误差,最后通过对比度敏感函数(CSF)取得不同子带的视觉误差加权系数,从而得到图像质量评价值。本文在具有5种类型降质图像的LIVE图库进行性能比较实验,结果表明本文所设计指标比峰值信噪比PSNR、结构相似度SSIM算法具有更好的稳定性和主客观评价一致性;同时试验表明通过对比度敏感函数(CSF)获取的加权对本图像质量评价指标改进较小。

关键词：图像质量评价人类视觉系统(HVS) Contourlet变换对比度敏感函数(CSF)

Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao Jiang Zengxin Qi Huixian Zhu Kangli shen Ruiqi Liu Chenxin Fang Weiwei Lou Yifan Jiang Wangrui yuan Xin Cao Liang Chen Qianxing Zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease