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The Dynamics of Vector Fields with Singularities

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Acta Mathematica Sinica,English Series 2022年第1期38卷 225-248页

作者： da wei YANG School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China

We give a brief survey on the dynamics of vector fields with *** aim of this survey is not to list all results in this field,but only to introduce some results from several viewpoints and some technics.

关键词： Vector filed singularity Morse–Smale horseshoe singular hyperbolicty

Topological phases of quantized light

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National Science Review 2021年第1期8卷 69-80页

作者： Han Cai da-wei Wang Interdisciplinary Center for Quantum Information and State Key Laboratory of Modern Optical Instrumentation Zhejiang Province Key Laboratory of Quantum Technology and Device and Department of Physics Zhejiang University CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Topological photonics is an emerging research area that focuses on the topological states of classical *** we reveal the topological phases that are intrinsic to the quantum nature of light, i.e. solely related to the quantized Fock states and the inhomogeneous coupling strengths between them. The Hamiltonian of two cavities coupled with a two-level atom is an intrinsic one-dimensional Su-Schriefer-Heeger model of Fock states. By adding another cavity, the Fock-state lattice is extended to two dimensions with a honeycomb structure, where the strain due to the inhomogeneous coupling strengths of the annihilation operator induces a Lifshitz topological phase transition between a semimetal and three band insulators within the lattice. In the semimetallic phase, the strain is equivalent to a pseudomagnetic field, which results in the quantization of the Landau levels and the valley Hall effect. We further construct an inhomogeneous Fock-state Haldane model where the topological phases can be characterized by the topological *** d cavities being coupled to the atom, the lattice is extended to d-1 dimensions without an upper limit. In this study we demonstrate a fundamental distinction between the topological phases in quantum and classical optics and provide a novel platform for studying topological physics in dimensions higher than three.

关键词： topological phases Su-Schriefer-Heeger model Jaynes-Cummings model strain-induced magnetic field Haldane model

A Note on ＂Global Exponential Convergence Analysis of Hopfield Neural Networks with Continuously Distributed Delays＂

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Communications in Theoretical Physics 2007年第6期47卷 1143-1144页

作者： CHANG da-wei Faculty of Mathematics and Information Science Shaanxi Normal University Xi＇an 710062 China

In this note, we would like to point out that （i） of Corollary 1 given by Zhang et al. （cf Commun. Theor. Phys. 39 （2003） 381） is incorrect in general.

关键词： Hopfield neural networks distributed delays equilibrium point globally exponential stability

Cauda equina syndrome with urinary retention as a postoperative complication of lumbar spine surgery:A case report

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World Journal of Clinical Cases 2025年第10期13卷 40-45页

作者： Kai-Wu Yang wei-Hong Lai da-wei Huang Department of Urology Chiayi Christian HospitalChiayi 600566Taiwan Department of Neurosurgery Chiayi Christian HospitalChiayi 600566Taiwan

BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or *** syndrome is commonly an indication for surgical intervention but has not been determined as a postoperative complication following surgery for lumbar spine *** SUMMARY To report the case of a 54-year-old male patient who had CES following spinal surgery,with no obvious compression lesions found during re-exploration,suggesting that vascular insufficiency may have contributed to the ***,a series of urodynamic studies on bladder recovery patterns in such complications have also been *** Postoperative CES requires urgent imaging and exploration to rule out compression;noncompressive cases,including vascular insufficiency may performed conservative management.

关键词： Cauda equina syndrome Lumbar spine surgery Urinary retention Urodynamic study Postoperative complication Case report

X-ray Emission Lines in GRB Afterglows: Evidence for a Two-component Jet Model

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Chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 571-578页

作者： wei-Hong Gao da-Ming wei Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

X-ray emission lines have been observed in X-ray afterglows of several T-ray bursts （GRBs）. It is a major breakthrough for understanding the nature of the progenitors. It has been proposed that the X-ray emission lines can be well explained by the Geometry-Dominated models, but in these models the illuminat- ing angle is much larger than that of the collimated jet of the GRB. For GRB 011211, we have obtained an illuminating angle of about 0 - 45°, while the angle of the GRB jet is only 3.6°. So we propose that the outflow of GRBs with emission lines should have two distinct components： a wide component that illuminates the reprocessing material and produces the emission lines and a narrow one that produces the GRB. Observations show the energy for producing the emission lines is higher than that of the GRB. In this case, when the wide component dominates the afterglows, a bump should appear in the GRB afterglow. For GRB 011211, the bump should occur within 0.05 days of the GRB, which is obviously too early for the observation to catch it. Alongside the X-ray emission lines there should also be a bright emission component between the UV and the soft X-rays. These features can be tested by the Swift satellite in the near future.

关键词： gamma rays: bursts -- line: profiles -- ISM: jets and outflows -- supernovae: general

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心态秩序:费孝通论中国式现代化的秩序之源

广西师范大学学报（哲学社会科学版） 2025年第1期61卷 128-136页

作者：刘大为马茳西北大学新闻传播学院陕西西安710127

心态秩序是理解费孝通晚年思想的核心概念,其内涵包含“从社会到人、从结构到心态”的方法论反思和全球性大社会中“秩序何以可能”的问题探索,强调中国现代转型进程中“道义关系”和“文化心态”的研究进路,经由“文化自觉”建构人与... 详细信息

心态秩序是理解费孝通晚年思想的核心概念,其内涵包含“从社会到人、从结构到心态”的方法论反思和全球性大社会中“秩序何以可能”的问题探索,强调中国现代转型进程中“道义关系”和“文化心态”的研究进路,经由“文化自觉”建构人与人遂生乐业、族与族多元一体、国与国和而不同的中国式文明新秩序。这套理念立足于融通中华文明传统和全人类共同价值,主张将丰富人民精神世界与推动构建人类命运共同体勾连起来,为解读中国式现代化进程和创造人类文明新形态提供了思想资源。

关键词：现代化道德秩序文明形态文化自觉文化心态

X-ray Flashes from Off-axis Nonuniform Jets

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Chinese Journal of Astronomy and Astrophysics 2004年第5期4卷 473-480页

作者： Zhi-Ping Jin da-Ming wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

It has been widely believed that the outflows in gamma-ray bursts are jetted and some jets may have structures like ∈(θ)∝θ-k. We check the possibility that X-ray flashes come from such jets. Both qualitative and quantitative analyses have shown that this model can reproduce most of the observational features of both X-ray flashes and gamma-ray bursts. Using the usual parameters of gamma-ray bursts, we have carried out numerical calculations for both uniform and nonuniform jets, of their fluxes, spectra and peak energies. It seems that nonuniform jets are more appropriate to these observational properties than uniform jets. We have also shown that in our model the observational ratio of gamma-ray bursts to X-ray flashes is about a few units.

关键词： X-rays general-gamma rays bursts-ISM jets and outflows

Predictive sliding-mode control of networked high-order fully actuated systems under random deception attacks

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Science China(Information Sciences) 2023年第9期66卷 50-63页

作者： da-wei ZHANG Guo-Ping LIU Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

This research addresses the output tracking of networked high-order fully actuated(NHOFA)systems under random deception attacks in the sensor to networked controller(SNC) and networked controller to actuator(NCA) communication channels, where a Bernoulli process represents the launching success rate of random deception attacks. A successful attack involves the output and control signals being tampered with by the injection of false data. Herein, a predictive sliding-mode control scheme is proposed to achieve the security tracking. In this scheme, a sliding-mode variable is introduced to defend the random deception attacks by enhancing the robustness of closed-loop systems. An incremental HOFA(IHOFA) prediction model is developed using a Diophantine equation as an alternative to the traditional reduced-order prediction model. Through this IHOFA prediction model, the multistep ahead predictions of the sliding-mode variable are constructed to optimize the tracking performance and defense of random deception attacks. By utilizing the Lyapunov function and linear matrix inequality(LMI) approach, a sufficient and necessary condition is proposed to ensure stability and high tracking performance of closed-loop NHOFA systems. Herein, an experiment on the tracking control of an air-bearing spacecraft(ABS) simulator is performed to demonstrate the effectiveness and practicability of the predictive sliding-mode control scheme.

关键词： NHOFA systems random deception attacks predictive sliding-mode control stability and tracking performance tracking control of ABS simulator

A review on system and materials for aqueous flexible metal-air batteries

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Carbon Energy 2023年第3期5卷 138-159页

作者： Lixue Jiang Xiaoxuan Luo da‐wei Wang School of Chemical Engineering The University of New South WalesSydneyNew South WalesAustralia

The exploration of aqueous flexible metal-air batteries with high energy density and durability has attracted many research efforts with the demand for portable and wearable electronic *** flexible metal-air batteries feature Earth-abundant materials,environmental friendliness,and operational *** part of one metal-air battery can significantly affect the overall *** review starts with the fundamental working principles and the basic battery configurations and then highlights on the common issues and the recent advances in designing high-performance metal electrodes,solid-state electrolytes,and air *** oxygen electrocatalysts with high activity and long-term stability for constructing efficient air electrodes in flexible metal-air batteries are summarized including metal-free carbon-based materials and nonprecious Co/Fe-based materials(alloys,metal oxides,metal sulfites,metal phosphates,metal nitrates,single-site metal-nitrogen-carbon materials,and composites).Finally,a perspective is provided on the existing challenges and possible future research directions in optimizing the performance and lifetime of the flexible aqueous solid-state metal-air batteries.

关键词： activity air electrodes flexible metal-air batteries oxygen electrocatalysts solid‐state electrolytes stability