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基于Transformer的状态−动作−奖赏预测表征学习

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自动化学报 2025年第1期51卷 117-132页

作者：刘民颂朱圆恒赵冬斌中国科学院自动化研究所多模态人工智能系统全国重点实验室北京100190 中国科学院大学人工智能学院北京100049

为了提升具有高维动作空间的复杂连续控制任务的性能和样本效率,提出一种基于Transformer的状态−动作−奖赏预测表征学习框架(Transformer-based state-action-reward prediction representation learning framework,TSAR).具体来说,TSAR提出一种基于Transformer的融合状态−动作−奖赏信息的序列预测任务.该预测任务采用随机掩码技术对序列数据进行预处理,通过最大化掩码序列的预测状态特征与实际目标状态特征间的互信息,同时学习状态与动作表征.为进一步强化状态和动作表征与强化学习(Reinforcement learning,RL)策略的相关性,TSAR引入动作预测学习和奖赏预测学习作为附加的学习约束以指导状态和动作表征学习.TSAR同时将状态表征和动作表征显式地纳入到强化学习策略的优化中,显著提高了表征对策略学习的促进作用.实验结果表明,在DMControl的9个具有挑战性的困难环境中,TSAR的性能和样本效率超越了现有最先进的方法.

关键词：深度强化学习表征学习自监督对比学习 Transformer

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两阶段特征迁移图像去雾算法

计算机工程与应用 2025年第4期61卷 241-252页

作者：袁姮颜廷昊张晟翀辽宁工程技术大学软件学院辽宁葫芦岛125105 光电信息控制和安全技术重点实验室天津300308

针对常见去雾算法处理后图像容易产生伪影、颜色失真以及对非均匀雾气影响下图像的去雾效果不理想等问题,提出了两阶段特征迁移图像去雾算法,基于编解码器结构实现图像去雾。第一阶段将清晰图像送入特征学习网络,通过混合注意力机制学... 详细信息

针对常见去雾算法处理后图像容易产生伪影、颜色失真以及对非均匀雾气影响下图像的去雾效果不理想等问题,提出了两阶段特征迁移图像去雾算法,基于编解码器结构实现图像去雾。第一阶段将清晰图像送入特征学习网络,通过混合注意力机制学习清晰图像空间结构信息与色彩规律。第二阶段利用特征迁移损失,将特征学习网络中学习到的清晰图像特征知识迁移至特征细化图像去雾网络中,并通过多尺度特征提取模块与全局特征细化块对图像上下文信息进行有效提取与融合。最后将两阶段输出进行特征融合,恢复清晰无雾图像。实验结果表明,该算法在RESIDE数据集以及真实非均匀雾天图像中具备较好的去雾效果,且处理后图像色彩合理,更加符合人类视觉感知。

关键词：图像去雾卷积神经网络特征迁移特征学习混合注意力机制全局特征细化

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特征重排列注意力机制的双池化残差分类网络

中国图象图形学报 2025年第1期30卷 110-129页

作者：袁姮刘杰姜文涛刘万军辽宁工程技术大学软件学院葫芦岛125105

目的针对残差图像分类网络中通道信息交互不充分导致通道特征没有得到有效利用,同时残差结构使部分特征信息丢失的问题,本文提出特征重排列注意力机制的双池化残差分类网络(double-pooling residual classification network of feature ... 详细信息

目的针对残差图像分类网络中通道信息交互不充分导致通道特征没有得到有效利用,同时残差结构使部分特征信息丢失的问题,本文提出特征重排列注意力机制的双池化残差分类网络(double-pooling residual classification network of feature reordering attention mechanism,FDPRNet)。方法FDPRNet以ResNet-34(residual network)残差网络为基础,首先将第1层卷积核尺寸从7×7替换为3×3,保留更多的特征信息,增强网络非线性表达能力,同时删除最大池化层,提高局部细节捕捉能力;然后,提出特征重排列注意力机制(feature reordering attention mechanism,FRAM)模块,将特征图通道进行分组,对其进行组间和组内重排序,通过一维卷积提取各通道组合的特征并拼接,得到重排列特征的权重;最后,提出了双池化残差(double-pooling residual,DPR)模块,该模块使用最大池化和平均池化并行操作特征图,并对池化后的特征图进行逐元素相加和卷积映射,以提取关键特征,减小特征图尺寸。结果在CIFAR-100(Canadian Institute for Advanced Research)、CIFAR-10和SVHN(street view house numbers)数据集上与其他11种图像分类网络进行比较,相比于性能第2的模型RTSA Net-101(residual Net-101 with tensorsynthetic attention),准确率分别提高了1.16%、1.01%和0.98%。实验结果表明FDPRNet显著提升了分类准确率。结论本文提出的FDPRNet具有增强图像通道内部信息交流和减少特征丢失的能力,不仅在分类精度上表现出较高水平,而且显著提升了模型的泛化能力。

关键词：图像分类特征重排列注意力机制残差网络深度学习

Design of a tunable mass damper for mitigating vibrations in milling of cylindrical parts

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Chinese Journal of Aeronautics 2019年第3期32卷 748-758页

作者： heng yuan Min WAN Yun YANG School of Mechanical Engineering Northwestern Polytechnical University State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical University

Milling the free-end of cylindrical parts, which are vertically fixed on the machine table,often suffers from large chatter vibrations. This kind of phenomenon is harmful to the cutting process. Therefore, it is of great importance to develop means to suppress these undesirable *** paper proposes a new idea for designing a tunable mass damper(TMD) to reduce vibrations in milling of cylindrical parts. Frequency response function(FRF) of the milling system is derived to comprehensively reveal the influence of both the dynamic response of the machine tools and the TMD. Critical axial depth of cut, which is usually used to characterize the process stability, is formulated by considering the FRFs of both the milling system itself and the TMD. Maximization of critical axial depth of cut is taken as objective function, while kernel dynamic parameters of TMD,which are involved in the derived expression of critical axial depth of cut, are extracted as designable variables. Optimization procedure is carried out to adjust the parameters of TMD by using sequential quadratic programming algorithm. A series of experiments with a designed passive TMD validate that the design has a good performance in reducing vibrations and improving stability of milling process.

关键词： Chatter Milling Mitigation of vibrations Stability Tunable mass damper (TMD)

Active Damping of Milling Vibration Using Operational Amplifier Circuit

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 58-65页

作者： Bashir Bala Muhammad Min Wan Yang Liu heng yuan School of Mechanical Engineering Northwestern Polytechnical University

The problem of chatter vibration is associated with adverse consequences that often lead to tool impairment and poor surface finished in a workpiece, and thus, controlling or suppressing chatter vibrations is of great significance to improve machining quality. In this paper, a workpiece and an actuator dynamics are considered in modeling and controller design. A proportional-integral controller(PI) is presented to control and actively damp the chatter vibration of a workpiece in the milling process. The controller is chosen on the basis of its highly stable output and a smaller amount of steady-state error. The controller is realized using analog operational amplifier circuit. The work has contributed to planning a novel approach that addresses the problem of chatter vibration in spite of technical hitches in modeling and controller design. The method can also lead to considerable reduction in vibrations and can be beneficial in industries in term of cost reduction and energy saving. The application of this method is verified using active damping device actuator(ADD) in the milling of steel.

关键词： Active damping Anti-windup Bending moment Milling process Workpiece vibration Operational amplifier Proportional integral controller

Determination of optimal geometrical parameters of peripheral mills to achieve good process stability

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Advances in Manufacturing 2018年第3期6卷 259-271页

作者： Min Wan heng yuan Ying-Chao Ma Wei-Hong Zhang School of Mechanical Engineering Northwestern Polytechnical University Xi'an 710072 Shaanxi People'sRepublic of China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an 710072 Shaanxi People's Republic of China

This paper focuses on optimization of the geo-metrical parameters of peripheral milling tools by takinginto account the dynamic effect. A substructure synthesistechnique is used to calculate the frequency responsefunction of the tool point, which is adopted to determinethe stability lobe diagram. Based on the Taguchi designmethod, simulations are first conducted for varying com-binations of tool overhang length, helix angle, and teethnumber. The optimal geometrical parameters of the tool aredetermined through an orthogonal analysis of the maxi-mum axial depth of cut, which is obtained from the pre-dicted stability lobe diagram. It was found that thesequence of every factor used to determine the optimal toolgeometrical parameters was the tool overhang length, teethnumber, and helix angle. Finally, a series of experimentswere carried out as a parameter study to determine theinfluence of the tool overhang length, helix angle, and teethnumber on the cutting stability of a mill. The same con-clusion as that obtained through the simulation wasobserved.

关键词： Substructure synthesis technique Frequencyresponse function Tool geometrical parameter Taguchidesign method

Recent Advances in C_(2) Gases Separation and Purification by Metal-Organic Frameworks

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Chinese Journal of Structural Chemistry 2022年第11期41卷 31-44页

作者： Zhengyi Di Xinjing Zheng Yu Qi heng yuan Cheng-Peng Li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002.China

Separation of C_(2) gases(C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2))mixtures is one of the most important and energy-demanding processes in chemical *** separation methods(fine distillation separation and selective catalytic hydrogenation separation)have the shortages of high energy consumption and inefficient use of resources,affecting the achievement of peak carbon dioxide emissions and carbon neutrality *** based on adsorption is considered as one of the best ways to achieve low-energy ***,it is of great importance to synthesize materials that enable the effective separation and purification of C_(2) gases under mild *** an emerging class of porous materials,metal-organic frameworks(MOFs)show great promise in the field of gas separation and purification due to their ultra-high specific surface area,easily modifiable pore surfaces,structural designability and ***,we summarize recent research advances by use of MOFs sorbents for the separation and purification of C_(2) gases,including C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2).Relationship between structures and separation mechanism is also ***,challenges and possible research directions related to the further exploration are also discussed.

关键词： MOFs adsorption and separation C_(2)gas design and synthesis pore size

Theoretical and numerical research on effect of tension mechanisms in strip flatness electromagnetic control rolling mills

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Journal of Iron and Steel Research International 2024年第9期31卷 2217-2235页

作者： Ting-song Yang Tie-heng yuan Wen-quan Sun An-rui He Chun-tao Qu National Engineering Research Center of Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China Institute of Aeronautical Power Machinery AECC Harbin Dongan Engine Co.Ltd.Harbin150000HeilongjiangChina

To achieve stable rolling,the influence of a tension mechanism of a large diameter ratio roll system on the rolling process of a strip flatness electromagnetic control rolling mill is *** the analysis of the rolling deformation zone,the deformation zone composition form of a large diameter ratio roll system and a calculation formula of neutral angle under tension are *** analyze the effect of front and post tensions on the rolling characteristic and the strip flatness control characteristic,a three-dimensional rolling finite element(FE)model of a large diameter ratio roll system with the function of roll profile electromagnetic control is established by FE software and verified by a strip flatness electromagnetic control rolling *** on the model,the strip thickness characteristic,metal transverse flow,strip flatness state,and adjustment range of the loaded roll gap are analyzed for different front and post tensions setting *** results show that changing the front or post tension setting values can improve the single-pass reduction rate of a large diameter ratio roll system and have little effect on the flatness control ability of the strip flatness electromagnetic control rolling mill.

关键词： Strip flatness electromagnetic control rolling mill Tension mechanism Roll profile electromagnetic control technology Rolling characteristic Strip flatness control characteristic

Covalent Organic Frameworks(COFs) for Sequestration of ^(99)TcO_(4)^(–)

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Chemical Research in Chinese Universities 2022年第2期38卷 290-295页

作者： DI Zhengyi MAO Yining yuan heng ZHOU Yan JIN Jun LI Cheng-Peng College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387P.R.China

Covalent organic frameworks(COFs),as a class of crystalline porous materials with periodic lattices and porous structures,have received extensive attention in the fields of gas storage and separation,energy storage,catalysis and optoelectronics and so ***,COFs are still in their infancy in the field of nuclear waste treatment,especially for sequestration of long-live problematic radionuclides,such as *** of decontamination of pertechnetate(TcO4–),a main existence of 99Tc under aerobic environments,is far from *** this review,recent progresses of COFs and some relative materials in the sequestration of pertechnetate,and perspective on surmounting the unmet issues are elucidated.

关键词： Covalent organic framework(COF) Radionuclide sequestration 99TcO4– Adsorption Anion exchange