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Higher-order temporal interactions promote the cooperation in the multiplayer snowdrift game

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Science China(Information Sciences) 2023年第12期66卷 138-153页

作者： Yan xu juan WANG Chengyi XIA Zhen WANG School of Computer Science and Engineering Tianjin University of Technology School of Electrical Engineering and Automation Tianjin University of Technology School of Artificial Intelligence Tiangong University School of Cyberspace and Center for OPTical IMagery Analysis and Learning(OPTIMAL) Northwestern Polytechnical University

To explore evolutionary dynamics of collective behaviors within the interconnected population,previous studies usually map non-pairwise interactions to higher-order static networks. However, from human communications to chemical reactions and biological systems, interactions often change over time, which cannot be simply described by higher-order static networks. In this study, we introduce time effects into higher-order networks and correspondingly investigate the evolutionary dynamics of multiplayer snowdrift games on higher-order temporal networks. Specifically, extensive simulations from four empirical datasets reveal that(1) the temporal effect of higher-order networks can facilitate the evolution of cooperation;(2) the higher-order topology can enhance the emergence of cooperation within a certain range of parameters;(3) the contribution of temporal burstiness and participants burstiness to cooperation is reversed. Furthermore,we theoretically demonstrate that the higher-order structure will suppress the propagation of defection in temporal networks. Our findings offer a new avenue for studying the evolution of altruistic behaviors in realistic complex networks.

关键词： collective behaviors non-pairwise interactions multiplayer snowdrift games temporal networks higher-order complex networks

Wavelength-Tunable Rectangular Pulse Dissipative Soliton Operation of an Erbium-Doped Mode-Locked Fiber Laser

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Chinese Physics Letters 2014年第4期31卷 68-71页

作者： HU xue-juan GUO chun-Yu RUAN Shuang-Chen Shenzhen Key Laboratory of Laser Engineering Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes College of Electronic Science and Technology Shenzhen University Shenzhen 518060

The wavelength-tunable rectangular pulse dissipative soliton （DS） is experimentally demonstrated, for the first time to the best of our knowledge, in an erbium-doped figure-of-eight fiber laser based on the nonlinear amplifying loop mirror mode-locked technique. The proposed rectangular pulse DS fiber laser can operate in the wavelength- tunable mode-locked state from 1573.5nm to 159d.6 nm with the rotation of the polarization controllers. The achieved output wavelengths are 1573.5nm, 1576.3nm, 1586.8nm, 1590.4nm and 1594.6nm, respectively. The pulse widths of the rectangular pulse can also be tuned from ~8ns to ~24ns by adjusting the pump power. The fundamental repetition rate of the rectangular pulse DS is 1.154 MHz and the output power is 6.1d m W （at 1594.6 nm）.

关键词： Laser Wavelength-Tunable first

A survey of photon mapping state-of-the-art research and future challenges

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 185-199页

作者： chun-meng KANG Lu WANG Yan-ning xu Xiang-xu MENG Department of Computer Science and Technology Shandong University Engineering Research Center of Digital Media Technology Ministry of Education

Global illumination is the core part of photo-realistic rendering. The photon mapping algorithm is an effective method for computing global illumination with its obvious advantage of caustic and color bleeding rendering. It is an active research field that has been developed over the past two decades. The deficiency of precise details and efficient rendering are still the main challenges of photon mapping. This report reviews recent work and classifies it into a set of categories including radiance estimation, photon relaxation, photon tracing, progressive photon mapping, and parallel methods. The goals of our report are giving readers an overall introduction to photon mapping and motivating further research to address the limitations of existing methods.

关键词： Global illumination Photon mapping Radiance estimation Photon relaxation Progressive photon mapping

Effect of Tube Spinning With Subsequent Heat-Treatment on Performance and Microstructure Evolution of T250 Maraging Steel

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Journal of Iron and Steel Research International 2012年第5期19卷 63-68页

作者： HU Zheng-fei WANG chun-xu School of Material Science and Engineering Tongji UniversityShanghai 200092China China Iron and Steel Institute Group Beijing 100081China

The effects of spinning deformation and subsequent heat treatments on the mechanical properties and microstructure of 18Ni Co-free Maraging steel （T250） tube were evaluated comparatively with the perform. An obvious radial shrinkage is detected in spun tubes after heat treatment and the magnitude of the shrinkage induced by solution treatment is almost the same as that by aging. Plastic deformation during spinning elongated the grains severely in the direction of metal flow. The solution treatment resulted in a drastically refined grain and recrystallised microstructure, removing the effect of plastic deformation, relieving the tangential residual stress and strain and improving hardness. Subsequent aging obtained a tempered microstructure, enhancing hardness values strikingly for precipitation strengthening. XRD （X-ray diffraction） analysis indicated that the reversed austenite formed in a plate-like along the grain boundaries and the volume fraction of austenite in spun tube was more than double that in the preform. These results imply that the residual stress and stain induced by spinning process and reversed austenite forming during aging might have the similar contribution to the radical shrinkage.

关键词： maraging steel spinning process plastic deformation heat-treatment microstructure reversed austenite

Analysis and Improvement of an Efficient Controlled Quantum Secure Direct Communication and Authentication Protocol

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Computers, Materials & Continua 2018年第12期57卷 621-633页

作者： Jifeng Zhong Zhihao Liu juan xu Navigation College Jimei UniversityXiamen361021China School of Computer Science and Engineering Southeast UniversityNanjing211189China Key Laboratory of Computer Network and Information Integration Southeast UniversityMinistry of EducationNanjing211189China Institute for Quantum Computing University of WaterlooWaterlooONCanadaN2L3G1

The controlled quantum secure direct communication(CQSDC)with authentication protocol based on four particle cluster states via quantum one-time pad and local unitary operations is *** is found that there are some serious security issues in this *** eavesdropper(Eve)can eavesdrop on some information of the identity strings of the receiver and the controller without being detected by the selective-CNOT-operation(SCNO)*** the same attack,Eve can also steal some information of the secret message that the sender *** addition,the receiver can take the same kind of attack to eavesdrop on some information of the secret message out of the control of the *** means that the requirements of CQSDC are not *** last,we improve the original CQSDC protocol to a secure one.

关键词： Quantum cryptography controlled quantum secure direct communication selective-CNOT-operation attack

A Memory-efficient Simulation Method of Grover’s Search Algorithm

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Computers, Materials & Continua 2018年第11期57卷 307-319页

作者： xuwei Tang juan xu Bojia Duan College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjingChina Institute for Quantum Computing University of WaterlooCanada Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of EducationChina

Grover’s search algorithm is one of the most significant quantum algorithms,which can obtain quadratic speedup of the extensive search *** Grover's search algorithm cannot be implemented on a real quantum computer at present,its quantum simulation is regarded as an effective method to study the search *** simulating the Grover's algorithm,the storage space required is exponential,which makes it difficult to simulate the high-qubit Grover’s *** this end,we deeply study the storage problem of probability amplitude,which is the core of the Grover simulation *** propose a novel memory-efficient method via amplitudes compression,and validate the effectiveness of the method by theoretical analysis and simulation *** results demonstrate that our compressed simulation search algorithm can help to save nearly 87.5%of the storage space than the uncompressed *** under the same hardware conditions,our method can dramatically reduce the required computing nodes,and at the same time,it can simulate at least 3 qubits more than the uncompressed ***,our memory-efficient simulation method can also be used to simulate other quantum algorithms to effectively reduce the storage costs required in simulation.

关键词： Grover’s search algorithm probability amplitude quantum simulation memory compression

Three Solutions of p-Laplacian Equations Via a Critical Point Theorem of Ricceri

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 171-178页

作者： chun-yan xuE He-yu xu School of Science Beijing Information Science and Technology University School of Mathematics Beijing Institute of Technology

In this paper,we consider the following quasilinear diferential equation（p（u′））′＋λf（t,u）=0subject to one of the two boundary conditions：u（0）=u′（1）=0,u′（0）=u（1）=*** transforming them into a problem of symmetrical solutions,the existence of three solutions of the problem is obtained by using a recent critical point theorem of *** example is given to demonstrate our main result.

关键词： boundary value problem critical point theorem three solutions symmetrical solution

Roles of voltage in semi-insulating GaAs photoconductive semiconductor switch

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Chinese Physics B 2017年第1期26卷 493-497页

作者： Hai-juan Cui Hong-chun Yang Jun xu Yu-Ming Yang Zi-Xian Yang School of Physical Electronics University of Electronic Science and Technology of China Chengdu 610054 China School of Mathematical Sciences University of Electronic Science and Technology of China Chengdu 610054 China

An experimental study of leakage current is presented in a semi-insulating（SI） Ga As photoconductive semiconductor switch（PCSS） with voltages up to 5.8 kV（average field is 19.3 kV/cm）. The leakage current increases nonlinearly with the bias voltage increasing from 1.2×10^-9 A to 3.6×10^-5A. Furthermore, the dark resistance, which is characterized as a function of electric field, does not monotonically decrease with the field but displays several distinct regimes. By eliminating the field-dependent drift velocity, the free-electron density n is extracted from the current, and then the critical field for each region of n（E） characteristic of PCSS is obtained. It must be the electric field that provides the free electron with sufficient energy to activate the carrier in the trapped state via multiple physical mechanisms, such as impurity ionization, fielddependent EL2 capture, and impact ionization of donor centers EL10 and EL2. The critical fields calculated from the activation energy of these physical processes accord well with the experimental results. Moreover, agreement between the fitting curve and experimental data of J（E）, further confirms that the dark-state characteristics are related to these field-dependent processes. The effects of voltage on SI-Ga As PCSS may give us an insight into its physical mechanism.

关键词： photoconductive semiconductor switch leakage current dark resistance nonlinear characteristics

On Principal Invariant Subspaces

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1621-1628页

作者： Xiao Ming xu Xiao chun FANG School of Science Shanghai Institute of Technology Department of Mathematics Tongji University

Let F and G be closed subspaces of the complex Hilbert spaceH, and U and V be closed subspaces of F- and G, respectively. In this paper, using the technique of operator block, we present the necessary and sufficient conditions under which （U, V） is a pair of （strictly, non-degenerate） principal invariant subspaces for （F, G）.

关键词： Hilbert space operator matrix invariant subspace principal invariant subspace