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A FAMILY OF THE LOCAL CONVERGENCE OF THE IMPROVED SECANT METHODS FOR NONLINEAR EQUALITY CONSTRAINED OPTIMIZATION SUBJECT TO BOUNDS ON VARIABLES

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Journal of Systems Science & Complexity 2014年第2期27卷 307-326页

作者： ZHANG Yong ZHU Detong School of mathematics and physics Changzhou University mathematics and Science college Shanghai Normal University

This paper studies a family of the local convergence of the improved secant methods for solving the nonlinear equality constrained optimization subject to bounds on variables. The Hessian of the Lagrangian is approximated using the DFP or the BFGS secant updates. The improved secant methods are used to generate a search direction. Combining with a suitable step size, each iterate switches to trial step of strict interior feasibility. When the Hessian is only positive definite in an affine null subspace, one shows that the algorithms generate the sequences converging q-linearly and two-step q-superlinearly. Yhrthermore, under some suitable assumptions, some sequences generated by the algorithms converge locally one-step q-superlinearly. Finally, some numerical results are presented to illustrate the effectiveness of the proposed algorithms.

关键词： Affine scaling local convergence secant methods second order correction.

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CROSS-DIFFUSION INDUCED TURING PATTERNS IN A SEX-STRUCTURED PREDATOR-PREY MODEL

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International Journal of Biomathematics 2012年第4期5卷 39-61页

作者： JIA LIU HUA ZHOU LAI ZHANG college of mathematics and physics changzhou university changzhou 213016 P. R. China Department of mathematics The Technical university of Denmark DK 2800 Lyngby Denmark

In this paper, we consider a sex-structured predator prey model with strongly coupled nonlinear reaction diffusion. Using the Lyapunov functional and Leray Schauder degree theory, the existence and stability of both homogenous and heterogenous steady-states are investigated. Our results demonstrate that the unique homogenous steady-state is locally asymptotically stable for the associated ODE system and PDE system with self-diffusion. With the presence of the cross-diffusion, the homogeneous equilibrium is destabilized, and a heterogenous steady-state emerges as a consequence. In addition, the conditions guaranteeing the emergence of Turing patterns are derived.

关键词： Predator-prey model cross-diffusion turing pattern sex structure.

Efficient white-light-emitting lead-free halide double perovskites enabling full-spectrum pc-WLEDs

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Science China Materials 2025年第1期 305-306页

作者： Xiaoyong Huang college of physics and Optoelectronics Taiyuan University of Technology

With the rapid development of solid-state lighting, an important goal of phosphor-converted white light-emitting diodes (pc-WLEDs) is to provide a healthy and comfortable fullspectrum artificial light source with a co...

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Global dynamics for a live-virus-blood model with distributed time delay

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International Journal of Biomathematics 2017年第5期10卷 143-158页

作者： Ding-Yu Zou Shi-Fei Wang Xue-Zhi Li Department of physics and mathematics Changzhou University Changzhou 213016 P. R. China college of mathematics and physics Anyang Institute of Technology Anyang 455000 P. R. China

In this paper, the global properties of a mathematical modeling of hepatitis C virus （HCV） with distributed time delays is studied. Lyapunov functionals are constructed to establish the global asymptotic stability of the uninfected and infected steady states. It is shown that if the basic reproduction number R0 is less than unity, then the uninfected steady state is globally asymptotically stable. If the basic reproduction number R0 is larger than unity, then the infected steady state is globally asymptotically stable.

关键词： Hepatitis C virus distributed time delays live-virus-blood system global asymptotic stability Lyapunov functional.

Constraints on holographic QCD phase transitions from PTA observations

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical physics and college of physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational physics (Albert Einstein Institute) 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 StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Non-Gaussianity and decoherence of generalized photon-added coherent state as a Hermite-excited coherent state

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Chinese physics B 2012年第2期21卷 292-300页

作者： Li Heng-Mei Xu Xue-Fen School of Science Changzhou Institute of TechnologyChangzhou 213002China School of mathematics and physics Jiangsu Teachers University of TechnologyChangzhou 213001China

Generalized photon-added coherent state （GPACS） is creation and annihilation operations on the coherent state. obtained by repeatedly acting the combination of Bose It is found that GPACS can be regarded as a Hermiteexcited coherent state due to its normalization factor related to a Hermite polynomial. In addition, we adopt the Hilbert-Schmidt distance to quantify the non-Gaussian character of GPACS and discuss the decoherence of GPACS in dissipative channel by studying the loss of nonclassicality in reference of the negativity of Wigner function.

关键词： generalized photon-added coherent state Hermite polynomial non-Gaussianity the negativity of Wigner function

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Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan Hou Xiaofei Qi Kan He college of mathematics Taiyuan University of Technology School of mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Inverse Dynamics of A 3-DOF Parallel Mechanism Based on Analytical Forward Kinematics

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 291-300页

作者： Ke Wang Ju Li Huiping Shen Jingjing You Tingli Yang Research Center for Advanced Mechanism Theory Changzhou UniversityChangzhou 213016China college of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210042China

For the development of a parallel mechanism(PM),it is necessary to establish a dynamic model which can accurately meet the requirements of real-time *** with the general dynamic analysis model based on the inverse kinematics,the dynamic analysis model based on the forward kinematics has the advantage of *** this paper,a new type of 3-DOF PM with analytical forward displacement analysis is *** from the general dynamic analysis based on the inverse kinematics,the displacement,velocity and acceleration equations of the PM are established and solved by forward *** inverse dynamic equation of the PM is constructed and solved by analyzing the forces on each link and based on Newton-Euler *** the theoretical results of an example are compared with the simulation results,which shows that the simulation results are basically consistent with the theoretical *** the maximum error of the driving force of each pair is 1.32%,5.8%and 5.2%,respectively,which verifies the correctness of the dynamic *** PM has a potential application prospect in the grasping,spraying and picking of *** research results of this paper provide a theoretical basis for the design,manufacture and application of the PM.

关键词： Parallel mechanism Dynamic model Newton-Euler method Simulation verification

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Escape from a Riddled-Like Basin

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Chinese physics Letters 2005年第12期22卷 3025-3028页

作者：巢小刚戴俊王文秀何大韧 college of physics Science and Technology Yangzhou University Yangzhou 225002 Information Science Department Jiangsu Polytechnic University Changzhou 213016

We investigate a system described by a conservative and a dissipative map concatenation. A fat fractal forbidden net, induced by interaction between discontinuous and noninvertible properties, introduces rippled-like attraction basins of two periodic attractors. Small areas, which serve as escaping holes of a new type of crisis, are dominated by conventional strong dissipation and are bounded by the forbidden region, but only in the vicinity of each periodic point. Based on this understanding, the scaling behaviour of the averaged lifetime of the crisis is analytically and numerically determined to be （τ） ∝ （b-b0）^γ, where b denotes the control parameter, bo denotes its critical threshold, and γ≌-1.5.

关键词： QUASI-DISSIPATIVE SYSTEM CRISIS ATTRACTORS WEB