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Science China(Information Sciences) 2024年第5期67卷 165-182页

作者： Bo CHEN jiangping hu Bijoy Kumar GHOSH School of Automation Engineering University of Electronic Science and Technology of China Key Laboratory of Intelligent Analysis and Decision on Complex Systems Chongqing University of Posts and Telecommunications Yangtze Delta Region Institute (huzhou) University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

The development of a distributed trajectory-tracking control strategy that is independent of velocity measurements is critical to achieving finite-time tracking control of autonomous underwater vehicle(AUV) systems. In this study, a group of heterogeneous AUV systems with intermittent communication links is considered and a finite-time trajectory-tracking control strategy is developed. The strategy includes two observers and one controller proposed for each follower-AUV. The first observer, a hybrid finite-time observer,estimates the state of the leader, whereas the second observer, which relies only on the position measurement,is proposed to estimate the states of the follower-AUV itself. In addition, a distributed trajectory-tracking controller is designed using the states estimated by the intermittent communication network even without velocity measurements. A homogeneous technique is utilized to prove that all followers can track the leader in a finite time. Finally, the effectiveness of the developed finite-time tracking control strategy is illustrated by numerical simulations.

关键词： distributed observer finite-time tracking homogeneous technique intermittent communication multiple heterogeneous AUVs

Flux phases in the extended hubbard model on the triangular lattice

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 148-153页

作者： Yuge Chen Kun Jiang Yi Zhang jiangping hu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics and Institute for Quantum Science and Technology Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of High Temperature Superconductors and International Center of Quantum and Molecular Structures Shanghai UniversityShanghai 200444China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China New Cornerstone Science Laboratory Beijing 100190China

Using the unrestricted Hartree-Fock variational method,we study the extended hubbard model in the triangular lattice at 3/4 *** to the nesting instability of the Fermi surface,various density wave states compatible with the 2×2 supercell are found as the ground state by tuning the onsite and nearest neighbor repulsions U and ***,the flux phases with complex bond order parameters are realized in a wide range of the U-V phase *** also acquire nontrivial topological properties due to the spontaneous breaking of the time-reversal *** study suggests that the flux phases can be stabilized by the interplay between short-range repulsive interactions in correlated electron systems.

关键词： flux state triangular lattice hubbard model

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Safe formation control of multiple unmanned aerial vehicles:control design and safety-stability analysis

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Control Theory and Technology 2024年第3期22卷 442-454页

作者： Haoqi Li jiangping hu Qingrui Zhou Bijoy K.Ghosh School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Yangtze Delta Region Institute(huzhou) University of Electronic Science and Technology of ChinaHuzhou 313000ZhejiangChina Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79409-1042USA

Both safety and stability are primary performance criteria for multi-unmanned aerial vehicle(multi-UAV)systems in many coordination *** approaches often consider safety and stability *** is necessary and urgent to develop a safety-stability control strategy to merge these two performance *** this paper,a unified approach is developed to consider safety and stability for multi-UAV formation *** stability criterion is represented by a Lyapunov function and safety criterion is represented by a barrier function and then a relaxed converse control Lyapunov-barrier theorem is *** the help of a relaxed converse control Lyapunov-barrier function(RCCLBF),a distributed safety-stability formation control strategy is proposed for the multi-UAV *** transforming the solution of RCCLBF to a Lyapunovlike stabilization problem,we show that the proposed formation control strategy can drive the UAVs staying within a specified safe *** results are provided to validate the proposed safety-stability formation control strategy.

关键词： Multi-UAV system Formation control Lyapunov function Barrier function Stability with safety guarantee

Classification of high-ordered topological nodes towards Moiré flat bands in twisted bilayers

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 133-147页

作者： Fan Cui Congcong Le Qiang Zhang Xianxin Wu jiangping hu Ching-Kai Chiu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China RIKEN Interdisciplinary Theoretical and Mathematical Sciences(iTHEMS) Wako 351-0198Japan CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China New Cornerstone Science Laboratory Beijing 100190China

At magic twisted angles,Dirac cones in twisted bilayer graphene(TBG)can evolve into flat bands,serving as a critical playground for the study of strongly correlated *** chiral symmetry is introduced,rigorous mathematical proof confirms that the flat bands are locked at zero energy in the entire Moiré Brillouin zone(BZ).Yet,TBG is not the sole platform that exhibits this absolute band *** to this flatness phenomenon are topological nodes and their specific locations in the *** this study,considering twisted bilayer systems that preserve chiral symmetry,we classify various ordered topological nodes in base layers and all possible node locations across different ***,we constrain the node locations to rotational centers,such as Γ and M points,to ensure the interlayer coupling retains equal strength in all *** this classification as a foundation,we systematically identify the conditions under which Moiré flat bands ***,through the extension of holomorphic functions,we provide proof that flat bands are locked at zero energy,shedding light on the origin of the band ***,beyond Dirac cones,numerous twisted bilayer nodal platforms can host flat bands with a degeneracy number of more than two,such as four-fold,six-fold,and *** multiplicity of degeneracy in flat bands might unveil more complex and enriched correlation physics.

关键词： twisted bilayer systems high-ordered topological nodes Moriéflat bands high degeneracy

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Charge 4e superconductor: A wavefunction approach

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Science Bulletin 2024年第15期69卷 2328-2331页

作者： Pengfei Li Kun Jiang jiangping hu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China New Cornerstone Science Laboratory Beijing 100190China

The BCS theory of superconductivity is one of milestones in condensed matter physics, which successfully unveils the nature of this macroscopic quantum phenomenon at a microscopic level[1,2]. The essential ingredients for any superconductors (SCs) are the two-electron Cooper pairs and their phase coherence [2],where electrons bind together two by two and condense to form a coherent quantum state, as illustrated in Fig. 1a.

关键词： quantum superconductor coherent

低负荷血流限制和高强度抗阻运动对男性运动青年大腿微循环功能的影响

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中国组织工程研究 2025年第2期29卷 393-401页

作者：彭永胡江平朱欢湖北民族大学体育学院湖北省恩施市445000 广西民族师范学院体育学院广西壮族自治区崇左市532200

背景:微循环作为人体物质能量代谢交换的唯一场所,与人体运动能力密切相关。抗阻运动是提高微循环功能的有效方式,但也有研究指出血流限制训练也能提高微循环功能,且具有负荷小和安全性高等优点。目的:比较6周低负荷血流限制运动、高强... 详细信息

背景:微循环作为人体物质能量代谢交换的唯一场所,与人体运动能力密切相关。抗阻运动是提高微循环功能的有效方式,但也有研究指出血流限制训练也能提高微循环功能,且具有负荷小和安全性高等优点。目的:比较6周低负荷血流限制运动、高强度抗阻运动对运动型男性青年大腿微循环功能的影响,并从血管内皮功能角度探讨运动改善微循环功能的可能机制。方法:将湖北民族大学60名体育专业男性大学生按照随机数表法分为对照组、高强度抗阻运动组和低负荷血流限制运动组,每组20人。低负荷血流限制运动组进行6周(每周3次、每次90 min、运动强度为30%1RM)的低负荷血流限制运动;高强度抗阻运动组进行6周(每周3次、每次90 min、运动强度为70%1RM强度)的抗阻训练;对照组该时间段不进行任何形式的运动训练。分别在干预开始的前1 d以及6周干预结束后次日的晨起空腹状态下对3组受试者微血管血流灌注量、经皮氧分压、肌氧饱和度、一氧化氮、内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子及大腿围、肌力等指标进行测试。结果与结论:①运动干预后,低负荷血流限制运动组和高强度抗阻运动组的微血管血流灌注量加热值、血细胞移动速度加热值与对照组及运动干预前相比有显著差异(P<0.05);低负荷血流限制运动组微血管血流灌注量加热值、血细胞移动速度加热值与高强度抗阻运动组相比有显著差异(P<0.05);经皮氧分压和肌氧饱和度与干预前相比有显著性差异(P<0.05)。②运动干预后,低负荷血流限制运动组和高强度抗阻运动组一氧化氮、内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子与对照组及运动干预前相比有显著差异(P<0.05)。③运动干预后,低负荷血流限制运动组和高强度抗阻运动组大腿围和大腿肌肉力量与运动干预前相比有显著差异(P<0.05)。④上述结果证实,6周低负荷血流限制运动和高强度抗阻运动可能通过调节内皮型一氧化氮合酶、内皮素1、血管内皮细胞生长因子等血管因子的分泌,提高体育专业大学生大腿微循环功能,并增加大腿肌肉的收缩力量,且低负荷血流限制运动对微血管血流灌注量、血细胞移动速度的干预效果更佳,因此低负荷血流限制运动较高强度抗阻运动在提高微循环功能方面更具优势。

关键词：低负荷血流限制高强度抗阻微循环功能肌肉力量微血管血流灌注量经皮氧分压肌氧饱和度一氧化氮内皮素1 血管内皮生长因子

Identifying the genes of unconventional high temperature superconductors

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Science Bulletin 2016年第7期61卷 561-569页

作者： jiangping hu Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China

We elucidate a recently emergent framework in unifying the two families of high temperature （high To） superconductors, cuprates and iron-based superconductors. The unification suggests that the latter is simply the counterpart of the former to realize robust extended s-wave pairing symmetries in a square lattice. The unification identifies that the key ingredients （gene） of high Tc superconductors is a quasi two dimensional electronic environment in which the d-orbitals of cations that partic- ipate in strong in-plane couplings to the p-orbitals of anions are isolated near Fermi energy. With this gene, the superexchange magnetic interactions mediated by anions could maximize their contributions to superconductivity. Creating the gene requires special arrangements between local electronic structures and crystal lattice structures. The speciality explains why high Tc superconductors are so rare. An explicit prediction is made to realize high Tc superconductivity in Co/Ni-based materials with a quasi two dimensional hexagonal lattice structure formed by trigonal bipyramidal complexes.

关键词： Cuprates Iron-based superconductors Unconventional high Tc superconducotors Superexchange

Topological quantum states of matter in iron-based superconductors:from concept to material realization

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National Science Review 2019年第2期6卷 213-226页

作者： Ning Hao jiangping hu Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory of Chinese Academy of Sciences Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences CAS Center of Excellence in Topological Quantum Computation and Kavli Institute of Theoretical Sciences University of Chinese Academy of Sciences Collaborative Innovation Center of Quantum Matter

We review recent progress in the exploration of topological quantum states of matter in iron-based superconductors. In particular, we focus on the non-trivial topology existing in the band structures and superconducting states of iron’s 3d orbitals. The basic concepts, models, materials and experimental results are reviewed. The natural integration between topology and high-temperature superconductivity in iron-based superconductors provides great opportunities to study topological superconductivity and Majorana modes at high temperature.

关键词： iron-based superconductor topological insulator topological superconductor spin–orbit coupling

具有高阶范霍夫奇点的自选轨道耦合体系中的鲁棒拓扑超导

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Science Bulletin 2024年第3期69卷 319-324页

作者：韩欣龙占俊张富春胡江平吴贤新 Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

Van Hove singularities in proximity to the Fermi level promote electronic interactions and generate diverse competing *** is also known that a nontrivial Berry phase derived from spin–orbit coupling can introduce an intriguing decoration into the interactions and thus alter correlated ***,it is unclear how and what type of new physics can emerge in a system featured by the interplay between van Hove singularities(VHSs)and the Berry ***,based on a general Rashba model on the square lattice,we comprehensively explore such an interplay and its significant influence on the competing electronic instabilities by performing a parquet renormalization group *** the existence of a variety of comparable fluctuations in the particle–particle and particle-hole channels associated with higher-order VHSs,we find that the chiral p±ip pairings emerge as two stable fixed trajectories within the generic interaction parameter space,namely the system becomes a robust topological *** chiral pairings stem from the hopping interaction induced by the nontrivial Berry *** possible experimental realization and implications are *** work sheds new light on the correlated states in quantum materials with strong spin–orbit coupling(SOC)and offers fresh insights into the exploration of topological superconductivity.

关键词： Van Hove singularity Topological superconductors Berry phase spin-orbit coupling

OPTIMAL TARGET TRAJECTORY ESTIMATION AND FILTERING USING NETWORKED SENSORS

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Journal of Systems Science & Complexity 2008年第3期21卷 325-336页

作者： jiangping hu Xiaoming hu Optimization and Systems Theory and ACCESS Linnaeus Center Royal Institute of Technology Stockholm 10044 Sweden

Target tracking using distributed sensor network is in general a challenging problem because it always needs to deal with real-time processing of noisy information. In this paper the problem of using nonlinear sensors such as distance and direction sensors for estimating a moving target is studied. The problem is formulated as a prudent design of nonlinear filters for a linear system subject to noisy nonlinear measurements and partially unknown input, which is generated by an exogenous system. In the worst case where the input is completely unknown, the exogenous dynamics is reduced to the random walk model. It can be shown that the nonlinear filter will have optimal convergence if the number of the sensors are large enough and the convergence rate will be highly improved if the sensors are deployed appropriately. This actually raises an interesting issue on active sensing： how to optimally move the sensors if they are considered as mobile multi-agent systems？ Finally, a simulation example is given to illustrate and validate the construction of our filter.

关键词： Optimal filter sensor network target tracking