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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin hu Jun cheng Zheng-Guang Wu huaicheng Yan IEEE Zhejiang University of Technology Guangxi Normal University Zhejiang University the East China University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

Color coded metadevices toward programmed terahertz switching

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Light(Science & Applications) 2024年第7期13卷 1383-1392页

作者： Weibao He Xiang’ai cheng Siyang hu Ziheng Ren Zhongyi Yu Shun Wan Yuze hu Tian Jiang College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangshaChina. Nanhu Laser Laboratory National University of Defense TechnologyChangshaChina. hunan Provincial Key Laboratory of High Energy Laser Technology National University of Defense TechnologyChangshaChina. Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangshaChina

Terahertz modulators play a critical role in high-speed wireless communication,non-destructive imaging,and so on,which have attracted a large amount of research ***,all-optical terahertz modulation,an ultrafast dynamical control approach,remains to be limited in terms of encoding and *** we experimentally demonstrated an optical-programmed terahertz switching realized by combining optical metasurfaces with the terahertz metasurface,resulting in 2-bit dual-channel terahertz *** terahertz metasurface,made up of semiconductor islands and artificial microstructures,enables effective all-optical programming by providing multiple frequency channels with ultrafast modulation at the nanosecond ***,optical metasurfaces covered in terahertz metasurface alter the spatial light field distribution to obtain color *** to the time-domain coupled mode theory analysis,the energy dissipation modes in terahertz metasurface can be independently controlled by color excitation,which explains the principle of 2-bit encoding *** work establishes a platform for all-optical programmed terahertz metadevices and may further advance the application of composite metasurface in terahertz manipulation.

关键词： terahertz surface excitation

Observations on spontaneous chiral symmetry breaking and the mass gap of QCD in finite volume

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Communications in Theoretical Physics 2024年第9期76卷 44-49页

作者： Xiaolan Meng Bolun hu yi-Bo Yang University of Chinese Academy of Sciences School of Physical Sciences CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCAS International Centre for Theoretical Physics Asia-Pacific

We present a lattice quantum chromodynamics(QCD) simulation with 2 + 1 + 1 flavor full QCD ensembles using near-physical quark masses and different spatial sizes L, at a ～ 0.055 *** results show that the scalar and pesudoscalar 2-point correlator with a valence pion mass of approximately 230 MeV become degenerated at L ≤ 1.0 fm, and such an observation suggests that the spontaneous chiral symmetry breaking disappears effectively at this point. At the same time, the mass gap between the nucleon and pion masses remains larger than ΛQCDin the entire L ∈ [0.2, 0.7] fm range.

关键词： chiral symmetry breaking confinement lattice QCD

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 74-86页

作者： Peng-Ju hu Liang Ma Hong Lü yi Pang Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Peng huanwu Center for Fundamental Theory Hefei 230026China

For asymptotically flat black holes,Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field ***,there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative *** of all,it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the *** then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conformal boundary of AdS black hole is not *** observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model,known as the Einstein-Weyl gravity,which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2-derivative *** thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity,one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field *** explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-Maxwell theory extended with generic 4-derivative interactions.

关键词： black holes thermodynamics higher-derivative corrections effective theories higher dimensional black holes quantum gravity

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DiriNet:An Estimation Network for Spectral Response Function and Point Spread Function

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Journal of Beijing Institute of Technology 2024年第4期33卷 287-297页

作者： Ting hu Siyuan cheng Chang Liu Beijing Key Laboratory of Computa-tional Intelligence and Intelligent System Faculty of Infor-mation TechnologyBeijing University of TechnologyBei-jing 100124China Space Star Technology Co. LtdBeijing 100086China Research Institute of Intelligent Wire-less Communication Network Technology Faculty of Infor-mation TechnologyBeijing University of TechnologyBei-jing 100124China.

Hyper-and multi-spectral image fusion is an important technology to produce hyper-spectral and hyper-resolution images,which always depends on the spectral response function andthe point spread ***,few works have been payed on the estimation of the two degra-dation *** learn the two functions from image pairs to be fused,we propose a Dirichletnetwork,where both functions are properly ***,the spatial response function isconstrained with positivity,while the Dirichlet distribution along with a total variation is imposedon the point spread *** the best of our knowledge,the neural network and the Dirichlet regularization are exclusively investigated,for the first time,to estimate the degradation *** image degradation and fusion experiments demonstrate the effectiveness and superiority of theproposed Dirichlet network.

关键词： Dirichlet network point spread function spectral response function hyper-spectralimage multi-spectral image

Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research(International) 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin cheng cheng-yang hu Yu-peng Zhang Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Basilic vein variation encountered during surgery for arm vein port:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2086-2091页

作者： cheng-Da hu Rui Lv Ya-Xin Zhao Ming-Hao Zhang Hong-Dou Zeng yi-Wen Mao Department of Breast Surgery The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly *** vein variation usually presents without any clinical symptoms and is often regarded as a benign *** case was a patient with congenital basilic vein variation encountered during surgery for an infusion *** SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port *** peculiarity has hitherto remained undescribed in the *** offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its *** conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port *** Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment.

关键词： Totally implantable venous access ports Arm ports Venous variation Postoperative breast cancer Systematic review Case report

An Adaptive Local Grid Nesting-based Genetic Algorithm for Multi-earth Observation Satellites' Area Target Observation

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 232-258页

作者： Ligang Xing Wei Xia Xiaoxuan hu Waiming Zhu yi Wu School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization and Inteligent Decision-making Ministry of EducationHefei 230009China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei 230009China

The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational *** advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of *** this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO ***,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational *** this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is *** effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different *** results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale *** fully demonstrate the high efficiency and stability of the ALGN-GA.

关键词： Multi-EOSs scheduling area target observation adaptive genetic algorithm local grid nesting

Organic Brønsted Acid-Catalyzed Stereoselective Cationic RAFT Polymerization:The Effect of RAFT Agents

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Chinese Journal of Polymer Science 2024年第6期42卷 711-717页

作者： Zheng-yi Zhang Zan Yang Yun Liao Sai-hu Liao Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108China State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing National Laboratory for Molecular Sciences Beijing100190China

The tacticity of vinyl polymers is a key factor affecting the properties of ***,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products ***,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of *** this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the *** extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.

关键词： Bronsted acid catalysis Stereoselective cationic polymerization RAFT polymerization Chain transfer agents Tacticity

Expression of human Papillomavirus in Mammary Carcinoma and its Possible Mechanism in Carcinogenesis

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Virologica Sinica 2008年第3期23卷 226-231页

作者： Chun-ling FAN Jing-hua ZHOU cheng-yi hu Heilongjiang August-first Land-Reclamation University Daqing 163319 China Heilongjiang Medical University Harbin 150040 China The 4th Hospital of Harbin Medical University Harbin China） Chinese 150010

To explore the role of human papillomavirus (HPV) in mammary carcinogenesis, the expression of the HPV-16, iNOS , P53 and hTERT proteins in breast carcinomas and their relationships were investigated. 52 samples of breast cancer and 16 samples of benign breast tumors were assayed using the immunohistochemical SP method for detection of protein expression levels. The expression of HPV-16, iNOS, P53 and hTERT proteins in a mammary carcinoma was 44.2%, 57.7%, 63.5% and 59.6% respectively, which was significantly greater than the corresponding levels in the benign group. The expression of iNOS, P53 and hTERT was correlated with the presence of an HPV-16 infection in a mammary carcinom(aP<0.05). The connection between these events might also involve the iNOS, mutated type P53 and the hTERT protein.

关键词：乳癌治疗方法乳突淋瘤临床分析