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Phase Synchronization in Coupled Oscillators: Dynamical Manifestations

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Chinese Physics Letters 2001年第7期18卷 874-877页

作者： ZHENG Zhi-gang hu gang Bambi hu Department of Physics Beijing Normal UniversityBeijing 100875 Department of Physics and Center for Nonlinear Studies Hong Kong Baptist UniversityHong Kong Department of Physics University of HoustonHouston TX77204USA

Phase synchronized entrainment of coupled oscillators with distributed natural frequencies is studied by exploring the dynamical *** route from partial to complete phase synchronization is identified as a cascade of transitions from high-to low-dimensional tori(quasiperiodicities)interrupted by intermittent *** ON-OFF intermittency is found at the onset of ***-induced chaos originates from the mixing of intermittent ON-OFF time scales.

关键词： chaos Phase chaos

Continuum damage mechanics based modeling progressive failure of woven-fabric composite laminate under low velocity impact

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 151-164页

作者： Zhi-gang hu Yan ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Arup Shanghai Shanghai 200031China

A continuum damage mechanics (CDM) meso-model was derived for both intraply and interply progressive failure behaviors of a 2D woven-fabric composite laminate under a transversely low velocity *** in-plane anisotropic damage constitutive model of a 2D woven composite ply was derived based on CDM within a thermodynamic framework,an elastic constitutive model with damage for the fibre directions and an elastic-plastic constitutive model with damage for the shear *** progressive failure behavior of a 2D woven composite ply is determined by the damage internal variables in different directions with appropriate damage evolution *** interface between two adjacent 2D woven composite plies with different ply orientations was modeled by a traction-separation law based interface *** isotropic damage constitutive law with CDM properties was used for the interface element,and a damage surface which combines stress and fracture mechanics failure criteria was employed to derive the damage initiation and evolution for the mixed-mode delamination of the interface *** analysis and experiments were both carried out on a 2D woven glass fibre/epoxy *** simulation results are in agreement with the experimental counterparts,verifying the progressive failure model of a woven composite *** proposed model will enhance the understanding of dynamic deformation and progressive failure behavior of composite laminate structures in the low velocity impact process.

关键词： Continuum damage mechanics (CDM) Woven composite laminate Low velocity impact Interface element Cohesive zone

Salp Swarm Incorporated Adaptive Dwarf Mongoose Optimizer with Lévy Flight and Gbest-Guided Strategy

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Journal of Bionic Engineering 2024年第4期21卷 2110-2144页

作者： gang hu Yuxuan Guo Guanglei Sheng Department of Applied Mathematics Xi’an University of TechnologyXi’an710054People’s Republic of China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China Department of Electronics and Information Engineering Bozhou UniversityBozhou236800People’s Republic of China

In response to the shortcomings of Dwarf Mongoose Optimization(DMO)algorithm,such as insufficient exploitation capability and slow convergence speed,this paper proposes a multi-strategy enhanced DMO,referred to as ***,we propose an improved solution search equation that utilizes the Gbest-guided strategy with different parameters to achieve a trade-off between exploration and exploitation(EE).Secondly,the Lévy flight is introduced to increase the diversity of population distribution and avoid the algorithm getting stuck in a local *** addition,in order to address the problem of low convergence efficiency of DMO,this study uses the strong nonlinear convergence factor Sigmaid function as the moving step size parameter of the mongoose during collective activities,and combines the strategy of the salp swarm leader with the mongoose for cooperative optimization,which enhances the search efficiency of agents and accelerating the convergence of the algorithm to the global optimal solution(Gbest).Subsequently,the superiority of GLSDMO is verified on CEC2017 and CEC2019,and the optimization effect of GLSDMO is analyzed in *** results show that GLSDMO is significantly superior to the compared algorithms in solution quality,robustness and global convergence rate on most test ***,the optimization performance of GLSDMO is verified on three classic engineering examples and one truss topology optimization *** simulation results show that GLSDMO achieves optimal costs on these real-world engineering problems.

关键词： Dwarf mongoose optimization algorithm Gbest-guided Lévy flight Adaptive parameter Salp swarm algorithm Engineering optimization Truss topological optimization

Generalized Tweakable Even-Mansour Cipher and Its Applications

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Journal of Computer Science & Technology 2018年第6期33卷 1261-1277页

作者： Ping Zhang Hong-gang hu Key Laboratory of Electromagnetic Space Information Chinese Academy of Sciences Hefei 230027 China School of Information Science and Technology University of Science and Technology of China Hefei 230027 China

This paper describes a generalized tweakable blockcipher HPH （Hash-Permutation-Hash）, which is based ona public random permutation P and a family of almost-XOR-universal hash functions H={HK}K∈κ as a tweak and keyschedule, and defined as y = HPHK（（t1, t2）, x） = P（x HK（t1）） HK（t2）, where K is a key randomly chosen from a keyspace/C, （tl, t2） is a tweak chosen from a valid tweak space T, x is a plaintext, and y is a ciphertext. We prove that HPHis a secure strong tweakable pseudorandom permutation （STPRP） by using H-coefficients technique. Then we focus on thesecurity of HPH against multi-key and related-key attacks. We prove that HPH achieves both multi-key STPRP security andrelated-key STPRP security. HPH can be extended to wide applications. It can be directly applied to authentication andauthenticated encryption modes. We apply HPH to PMAC1 and OPP, provide an improved authentication mode HPMACand a new authenticated encryption mode OPH, and prove that the two modes achieve single-key security, multi-key security,and related-key security.

关键词： tweakable blockcipher H-coefficients technique authentication authenticated encryption provable security

Transitions to Equilibrium State in Classical φ4 Lattice

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Communications in Theoretical Physics 2002年第8期38卷 157-162页

作者： WANG Xin-gang ZHANG Ying hu gang Department of Physics Beijing Normal University Beijing 100875 China The Abdus Salam International Centre for Theoretical Physics (ICTP) P.O. Box 586 34100 Trieste Italy Department of Physics Beijing Normal University Beijing 100875 China

Statistical behavior of a classical φ4 Hamiltonian lattice is investigated from microscopic dynamics. Thelargest Lyapunov exponent and entropies are considered for manifesting chaos and equipartition behaviors of the *** is found, for the first time, that for any large while finite system size there exist two critical couplings for the transitionsto equipartitions, and the scaling behaviors of these lower and upper critical couplings vs. the system size are numericallyobtained.

关键词： Hamiltonian system, measure synchronization, equilibrium, equipartition

Real-Time Simulation of Aeolian Sand Movement and Sand Ripple Evolution: A Method Based on the Physics of Blown Sand

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Journal of Computer Science & Technology 2012年第1期27卷 135-146页

作者： Ning Wang Bao-gang hu National Space Science Center Chinese Academy of SciencesBeijing 100190China Sino-French Laboratory for Computer Science Automation and Applied Mathematics/National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

Simulation and visualization of aeolian sand movement and sand ripple evolution are a challenging subject. In this paper, we propose a physically based modeling and simulating method that can be used to synthesize sandy terrain in various patterns. Our method is based on the mechanical behavior of individual sand grains, which are widely studied in the physics of blown sand. We accounted significant mechanisms of sand transportation into the sand model, such as saltation, successive saltation and collapsing, while simplified the vegetation model and wind field model to make the simulation feasible and affordable. We implemented the proposed method on the programming graphics processing unit （GPU） to get real-time simulation and rendering. Finally, we proved that our method can reflect many characteristics of sand ripple evolution through several demonstrations. We also gave several synthesized desert scenes made from the simulated height field to display its significance on application.

关键词： physically based modeling sand ripple evolution aeolian erosion particle systems GPU

Dynamic Behavior of Phase Synchronization of Chaos

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Chinese Physics Letters 2000年第5期17卷 332-334页

作者： ZHAN Meng hu gang WANG Xin-gang Department of Physics Beijing Normal UniversityBering 100875 China Center for Advanced Science and Technology(CCAST)(World Laboratory) P.O.Box 8730Beijing 100080

The dynamic nature of phase synchronization between chaotic outputs and injected periodic signals is *** find that the collapse of stroboscopic section from global distribution to local one and the loss of homogeneity of stroboscopic sections in chaotic attractors for different phases are the key features of this kind of phase synchronization,meanwhile the overall structure of chaotic attractor is not affected apparently by the phase synchronization.

关键词： chaotic Chaos attractor

Differential Evolution-Boosted Sine Cosine Golden Eagle Optimizer with Lévy Flight

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Journal of Bionic Engineering 2022年第6期19卷 1850-1885页

作者： gang hu Liuxin Chen Xupeng Wang Guo Wei Department of Applied Mathematics Xi’an University of TechnologyXi’an710054People’s Republic of China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China School of Art and Design Xi’an University of TechnologyXi’an710054China Department of Mathematics and Computer Science University of North Carolina at PembrokePembrokeNC28372USA

Golden eagle optimizer(GEO)is a recently introduced nature-inspired metaheuristic algorithm,which simulates the spiral hunting behavior of golden eagles in ***,the GEO suffers from the challenges of low diversity,slow iteration speed,and stagnation in local optimization when dealing with complicated optimization *** ameliorate these deficiencies,an improved hybrid GEO called IGEO,combined with Lévy flight,sine cosine algorithm and differential evolution(DE)strategy,is developed in this *** Lévy flight strategy is introduced into the initial stage to increase the diversity of the golden eagle population and make the initial population more abundant;meanwhile,the sine-cosine function can enhance the exploration ability of GEO and decrease the possibility of GEO falling into the local ***,the DE strategy is used in the exploration and exploitation stage to improve accuracy and convergence speed of ***,the superiority of the presented IGEO are comprehensively verified by comparing GEO and several state-of-the-art algorithms using(1)the CEC 2017 and CEC 2019 benchmark functions and(2)5 real-world engineering problems *** comparison results demonstrate that the proposed IGEO is a powerful and attractive alternative for solving engineering optimization problems.

关键词： Golden eagle optimizer Lévy flight Sine cosine algorithm Differential evolution strategy Engineering design Bionic model

Feedback Mechanism-driven Mutation Reptile Search Algorithm for Optimizing Interpolation Developable Surfaces

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Journal of Bionic Engineering 2024年第1期21卷 527-571页

作者： gang hu Jiao Wang Xiaoni Zhu Muhammad Abbas Department of Applied Mathematics Xi'an University of TechnologyXi'an 710054China School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China Department of Mathematics University of SargodhaSargodha 40100Pakistan

Curvature lines are special and important curves on *** is of great significance to construct developable surface interpolated on curvature lines in engineering *** this paper,the shape optimization of generalized cubic ball developable surface interpolated on the curvature line is studied by using the improved reptile search ***,based on the curvature line of generalized cubic ball curve with shape adjustable,this paper gives the construction method of SGC-Ball developable surface interpolated on the ***,the feedback mechanism,adaptive parameters and mutation strategy are introduced into the reptile search algorithm,and the Feedback mechanism-driven improved reptile search algorithm effectively improves the solving *** IEEE congress on evolutionary computation 2014,2017,2019 and four engineering design problems,the feedback mechanism-driven improved reptile search algorithm is compared with other representative methods,and the result indicates that the solution performance of the feedback mechanism-driven improved reptile search algorithm is *** last,taking the minimum energy as the evaluation index,the shape optimization model of SGC-Ball interpolation developable surface is *** developable surface with the minimum energy is achieved with the help of the feedback mechanism-driven improved reptile search algorithm,and the comparison experiment verifies the superiority of the feedback mechanism-driven improved reptile search algorithm for the shape optimization problem.

关键词： Reptile search algorithm Feedback mechanism Adaptive parameter Mutation strategy SGC-Ball interpolation developable surface Shape optimization