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基于稀疏表示的遥感图像超分辨重建

黑龙江大学自然科学学报 2019年第5期36卷 618-623页

作者：黄鑫朱福珍王成全巫红黑龙江大学电子工程学院哈尔滨150080 黑龙江东方学院计算机科学与电气工程学部哈尔滨150080

为了获取高质量的超分辨遥感图像,提出了一种改进特征提取算子的稀疏表示遥感图像超分辨率重建方法。该算法通过设置模板,对一阶和二阶梯度滤波算子进行改进,在有效提取低分辨率图像边缘特征的同时,减少噪声干扰。利用遥感图像库训练得... 详细信息

为了获取高质量的超分辨遥感图像,提出了一种改进特征提取算子的稀疏表示遥感图像超分辨率重建方法。该算法通过设置模板,对一阶和二阶梯度滤波算子进行改进,在有效提取低分辨率图像边缘特征的同时,减少噪声干扰。利用遥感图像库训练得到高、低分辨率图像块字典,再应用低分辨率图像块及其字典求出稀疏表示系数。高、低分辨率图像块具有相同的稀疏表示系数,可根据已求的稀疏表示系数得出超分辨重建图像。实验结果表明,改进算法的超分辨重建效果的客观评价指标,比以往稀疏表示超分辨方法有很大提高,峰值信噪比提高近0.24dB,均方根误差降低近0.15。

关键词：稀疏表示图像超分辨率字典训练特征提取

经皮冠状动脉介入治疗患者采用运动康复的效果观察

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反射疗法与康复医学 2020年第23期1卷 148-150页

作者：付跃超付鑫王成全邓立菊王妍敏大庆龙南医院(齐齐哈尔医学院第五附属医院) 黑龙江大庆163453

目的探究经皮冠状动脉介入治疗患者应用运动康复干预的临床效果。方法选取2018年11月—2019年11月于该院接受经皮冠状动脉介入治疗的患者100例为研究对象,将其进行随机分组,采用阿司匹林治疗的为对照组,采用运动康复干预的为试验组,探... 详细信息

目的探究经皮冠状动脉介入治疗患者应用运动康复干预的临床效果。方法选取2018年11月—2019年11月于该院接受经皮冠状动脉介入治疗的患者100例为研究对象,将其进行随机分组,采用阿司匹林治疗的为对照组,采用运动康复干预的为试验组,探究两组患者的临床干预效果。结果试验组患者干预后的6 min步行距离为(418.55±72.34)m,特定活动状态量表评分为(24.55±8.05)分,均显著优于对照组,组间差异有统计学意义(P0.05);试验组患者的抑郁严重指数低于对照组,一般自我效能、运动自我效能、生理机能、生理职能、精神健康和情感职能等评分均显著高于对照组,组间差异有统计学意义(P<0.05)。结论经皮冠状动脉介入治疗患者采用运动康复的效果显著,可促进患者恢复,提高患者生活质量,可在临床推广使用。

关键词：经皮冠状动脉介入运动康复生活质量

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铝合金船体结构应用带筋板的几个问题

船海工程 2003年第4期32卷 8-11页

作者：王承权戴海波杜述勇武汉南华高速船舶工程股份有限公司武汉430064

阐述应用带筋板的优越性,引荐带筋板的类型及尺寸系列,讨论含有带筋板的船体结构设计几个问题。

关键词：铝合金船带筋板结构设计船体结构

钢管-波纹钢板约束混凝土组合柱轴压性能有限元分析

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钢结构（中英文） 2023年第8期38卷 14-21页

作者：封剑森孙泽轩邹昀王城泉江苏华江祥瑞现代建筑发展有限公司江苏扬州225215 江南大学江苏无锡214122 浙大城市学院杭州310015

钢管-波纹钢板约束混凝土组合柱因其良好的受力性能以及快速的施工速度,在实际工程中得以广泛应用。为进一步研究钢管-波纹钢板约束混凝土组合柱的轴压性能,在已完成的6组轴压试验的基础上,利用ABAQUS有限元软件建立了相应的模型并进行... 详细信息

钢管-波纹钢板约束混凝土组合柱因其良好的受力性能以及快速的施工速度,在实际工程中得以广泛应用。为进一步研究钢管-波纹钢板约束混凝土组合柱的轴压性能,在已完成的6组轴压试验的基础上,利用ABAQUS有限元软件建立了相应的模型并进行了非线性有限元分析。结合轴压试验结果,从试件的破坏形态、荷载-位移曲线等方面证明了有限元模型的可靠性与适用性。基于已验证的有限元模型进行了大量的参数分析,研究的参数包括:混凝土强度、径宽比、波纹钢板屈服强度以及波纹钢板厚度,以探究不同参数对钢管-波纹钢板约束混凝土组合柱的承载能力、初始刚度、承载力提升系数、延性的影响。模拟结果表明:提升材料强度可以提高试件的承载能力,但对强度提升系数影响很小;增大径宽比可以有效提升试件的极限承载力、强度提升系数与延性,但相应试件的用钢量也会提升;增加波纹钢板厚度基本不会提升试件的承载能力,但会明显提高试件的延性。最后,进行了钢管-波纹钢板约束混凝土组合柱的稳定性分析,在综合考虑钢管-波纹钢板约束混凝土组合柱的截面形状以及材料性质的前提下,提出组合柱长细比的计算方法;通过引入初始缺陷的方式建立起不同长细比下钢管-波纹钢板约束混凝土组合柱的有限元模型,研究了不同长细比对其受力机理以及承载能力的影响,并引入各国规范的计算方法,将模拟结果与计算结果进行比较。对比结果表明:现有规范对于钢管-波纹钢板约束混凝土组合柱极限承载力的设计值偏大,不能准确预测组合柱的承载能力。因此,基于有限元模拟结果,对钢管-波纹钢板约束混凝土组合柱的稳定系数及轴压承载力计算公式进行了修正。

关键词：波形钢板轴压性能有限元模拟参数分析长细比

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Local-contrastive-learning machine with both generalization and adversarial robustness: A statistical physics analysis

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan Xie Yuchen wang Haiping Huang PMI Lab School of Physics Sun Yat-sen University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural networks trained by backpropagation can be easily fooled by adversarial examples. To design a semantically meaningful representation learning, we discard backpropagation, and instead, propose a local contrastive learning, where the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,while those of different labels repel(akin to fermion). This layer-wise learning is local in nature, being biologically plausible.A statistical mechanics analysis shows that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIST benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural networks

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei Zhou Siwei wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang wang Yasu Chen Jie Li Chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Flexible Graphene Field‑Effect Transistors and Their Application in Flexible Biomedical Sensing

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Nano-Micro Letters 2025年第2期17卷 252-313页

作者： Mingyuan Sun Shuai wang Yanbo Liang Chao wang Yunhong Zhang Hong Liu Yu Zhang Lin Han Institute of Marine Science and Technology Shandong UniversityQingdao 266237ShandongPeople’s Republic of China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongPeople’s Republic of China School of Integrated Circuits Shandong UniversityJinan 250100ShandongPeople’s Republic of China Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application Jinan250100ShandongPeople’s Republic of China

Flexible electronics are transforming our lives by making daily activities more *** to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabrication,low-power consumption,fast response times,and ***,known for its exceptional mechanical properties,high electron mobility,and biocompatibility,is an ideal material for FET channels and *** combination of graphene and FETs has given rise to flexible graphene field-effect transistors(FGFETs),driving significant advances in flexible electronics and sparked a strong interest in flexible biomedical ***,we first provide a brief overview of the basic structure,operating mechanism,and evaluation parameters of FGFETs,and delve into their material selection and patterning *** ability of FGFETs to sense strains and biomolecular charges opens up diverse application *** specifically analyze the latest strategies for integrating FGFETs into wearable and implantable flexible biomedical sensors,focusing on the key aspects of constructing high-quality flexible biomedical ***,we discuss the current challenges and prospects of FGFETs and their applications in biomedical *** review will provide valuable insights and inspiration for ongoing research to improve the quality of FGFETs and broaden their application prospects in flexible biomedical sensing.

关键词： Flexible Graphene Field-effect transistor Wearable Implantable Biosensor