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Novel self-embedding holographic watermarking image encryption protection scheme

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Chinese physics B 2024年第5期33卷 281-290页

作者：王励年周楠润孙博曹颖鸿牟俊 school of information Science and engineering Dalian Polytechnic UniversityDalian 116034 China school of electronic and Electrical engineering Shanghai University of Engineering ScienceShanghai 201620China

For digital image transmission security and information copyright,a new holographic image self-embedding watermarking encryption scheme is ***,the plaintext is converted to the RGB three-color channel,the corresponding phase hologram is obtained by holographic technology and the watermark is self-embedded in the frequency ***,by applying the Hilbert transform principle and genetic center law,a complete set of image encryption algorithms is constructed to realize the encryption of image ***,simulation results and security analysis indicate that the scheme can effectively encrypt and decrypt image information and realize the copyright protection of *** introduced scheme can provide some support for relevant theoretical research,and has practical significance.

关键词： color image encryption Hilbert transform self-embedding watermark holographic technology

Simultaneously enhancing erosion and compression resistance:designing AlCoCrFeNi high-entropy alloy strengthened Ag-based contacts

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Rare Metals 2024年第9期43卷 4476-4492页

作者： Xiao-Yang Xue Zhe Wang Hui-Ling Nie Zhao Yuan Jun Wang Chang-Hu Xu Kai Wen Cong-Hao Yu school of Materials Science and engineering Xi’an Polytechnic University school of physics Xi’an Jiaotong University Key Laboratory of Pulsed Power Technology School of Electrical and Electronic EngineeringHuazhong University of Science and Technology State Key Laboratory of Advanced Electromagnetic engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and Technology

Designing microstructures and unveiling dynamic erosion mechanisms remain important challenges for Ag-based contacts. To simultaneously enhance erosion and compression resistance, an Al Co Cr Fe Ni high-entropy alloy(HEA) is introduced into Ag-based materials to fabricate novel Ag-HEA contacts with island-and skeletonrestricted microstructures. The arc erosion experimental results reveal that the skeleton-restricted HEA microstructure is the key factor in reducing the hill and crater morphologies of the contact surface, effectively delaying material transfer between the movable and stationary contacts. The molten bridge evolution and compressive deformation behavior of Ag-HEA contacts with various microstructures are investigated using molecular dynamics(MD) simulations. MD results indicate that the constraint of Ag atom diffusion in the molten pool and the involvement of HEA atoms in the molten bridge are the primary mechanisms for improving erosion resistance. The skeleton-restricted HEA microstructure reduces the total energy and structural stability of the molten bridge system and promotes its fracture and disintegration. Moreover, the synergistic effect of the twin and Lomerz–Cottrell lock structures can hinder dislocation glide, generating dispersed and small-area stacking faults in the Ag matrix and mitigating the concentration of shear strains. Thus, the skeleton-restricted HEA microstructure contributes positively to compression resistance. This study presents a novel approach to designing Ag-based contacts.

关键词： Arc erosion Electrical contact materials High entropy alloys Microstructures Molecular dynamics

A novel variable-order fractional chaotic map and its dynamics

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Chinese physics B 2024年第3期33卷 281-290页

作者：唐周青贺少波王会海孙克辉姚昭吴先明 school of electronic information Central South UniversityChangsha 410083China school of Automation and electronic information Xiangtan UniversityXiangtan 411105China school of physics Central South UniversityChangsha 410083China school of Mechanical and Electrical engineering Guizhou Normal UniversityGuiyang 550025China

In recent years,fractional-order chaotic maps have been paid more attention in publications because of the memory *** paper presents a novel variable-order fractional sine map(VFSM)based on the discrete fractional ***,the order is defined as an iterative function that incorporates the current state of the *** analyzing phase diagrams,time sequences,bifurcations,Lyapunov exponents and fuzzy entropy complexity,the dynamics of the proposed map are investigated comparing with the constant-order fractional sine *** results reveal that the variable order has a good effect on improving the chaotic performance,and it enlarges the range of available parameter values as well as reduces non-chaotic *** coexisting attractors also enrich the dynamics of VFSM and prove its sensitivity to initial ***,the sequence generated by the proposed map passes the statistical test for pseudorandom number and shows strong robustness to parameter estimation,which proves the potential applications in the field of information security.

关键词： chaos fractional difference variable order multistability complexity

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical physics 2024年第5期76卷 77-85页

作者： Duo Zhang Ke Wang Kunpeng Zhao Mei Wang Zhaoyu Sun school of Electrical and electronic engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Two simple memristive maps with adaptive energy regulation and digital signal process verification

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Journal of Zhejiang university-Science A(Applied physics & engineering) 2024年第5期25卷 382-394页

作者： Feifei YANG Lujie REN Jun MA Zhigang ZHU College of Electrical and information engineering Lanzhou University of TechnologyLanzhou 730050China Department of physics Lanzhou University of TechnologyLanzhou 730050China school of information Science and engineering Dalian Polytechnic UniversityDalian 116034China

Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy *** involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive *** this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural *** corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear *** Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive *** Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and *** two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these *** scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.

关键词： Hamilton energy Discrete memristor Self-adaptive regulation Digital signal process(DSP)implementation

High-quality ghost imaging based on undersampled natural-order Hadamard source

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Chinese physics B 2024年第9期33卷 404-411页

作者： Kang Liu Cheng Zhou Jipeng Huang Hongwu Qin Xuan Liu Xinwei Li Lijun Song school of electronic information engineering Changchun UniversityChangchun 130022China school of physics Northeast Normal UniversityChangchun 130024China College of electronic and information engineering Changchun University of Science and TechnologyChangchun 130022China Jilin engineering Laboratory for Quantum information Technology Jilin Engineering Normal UniversityChangchun 130052China Changchun Institute of Technology Changchun 130012China

Improving the speed of ghost imaging is one of the main ways to leverage its advantages in sensitivity and imperfect spectral regions for practical *** of the proportional relationship between image resolution and measurement time,when the image pixels are large,the measurement time increases,making it difficult to achieve real-time ***,a high-quality ghost imaging method based on undersampled natural-order Hadamard is *** method uses the characteristics of the Hadamard matrix under undersampling conditions where image information can be fully obtained but overlaps,as well as deep learning to extract aliasing information from the overlapping results to obtain the true original image *** conducted numerical simulations and experimental tests on binary and grayscale objects under undersampling conditions to demonstrate the effectiveness and scalability of this *** method can significantly reduce the number of measurements required to obtain high-quality image information and advance application promotion.

关键词： ghost imaging natural-order Hadamard deep learning

Wireless Positioning:Technologies,Applications,Challenges,and Future Development Trends

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Computer Modeling in engineering & Sciences 2024年第5期139卷 1135-1166页

作者： Xingwang Li Hua Pang Geng Li Junjie Jiang Hui Zhang Changfei Gu Dong Yuan school of physics and electronic information engineering University of Henan PolytechnicJiaozuo454000China Jiaozuo Key Laboratory of Crow-Sensing Network Jiaozuo454000China Institute of Mining engineering Guizhou Institute of TechnologyGuiyang550003China Coal Supervision Department Panzhou Energy BureauPanzhou553599China

The development of the fifth-generation(5G)mobile communication systems has entered the commercialization stage.5G has a high data rate,low latency,and high reliability that can meet the basic demands of most industries and daily life,such as the Internet of Things(IoT),intelligent transportation systems,positioning,and *** continuous progress and development of society have aroused wide *** accuracy is the core demand for the applications,especially in complex environments such as airports,warehouses,supermarkets,and ***,many factors also affect the accuracy of positioning in those environments,for example,multipath effects,non-line-of-sight,and clock synchronization *** paper provides a comprehensive review of the existing works about positioning for the future wireless network and discusses its key techniques and algorithms,as well as the current development and future *** first outline the current traditional positioning technologies and algorithms,which are discussed and analyzed with the relevant *** addition,we also discuss application scenarios for wireless *** comparing different positioning systems,the challenges and future development directions of existing wireless positioning systems are prospected.

关键词： 5G wireless positioning reconfigurable intelligent surface Internet of Vehicles

Dynamic behavior analysis, color image encryption and circuit implementation of a novel complex memristive system

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Optoelectronics Letters 2024年第3期20卷 183-192页

作者： XIONG Li WANG Xuan ZHANG Xinguo HE Tongdi school of physics and Electromechanical engineering Hexi UniversityZhangye 734000China school of information Science and engineering Dalian Polytechnic UniversityDalian 116034China school of information Science and engineering Lanzhou UniversityLanzhou 730000China

This paper is devoted to introduce a novel four-dimensional memristor-involved system and its applications in image encryption and chaotic circuit. The typical dynamical behaviors of the memristor-involved system are explored, such as chaotic phase potraits, Lyapunov exponent spectrum(LES), bifurcation diagram(BD) and complexity analysis. Then a color image encryption algorithm is designed. In this algorithm, the sequences generated by the four-dimensional memristor-involved system are used in scrambling and diffusion algorithm for three channels.

关键词： image system chaotic

Ferroelectric BaTiO_(3) /Pr_(2)O_(3) heterojunction harvesting roomtemperature cold–hot alternation energy for efficiently pyrocatalytic dye decomposition

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Journal of Advanced Ceramics 2024年第1期13卷 44-52页

作者： Zheng Wu Taosheng Xu Luohong Zhang Tingting Liu Zhansheng Wu Gangqiang Zhu Yanmin Jia school of Environmental and Chemical engineering Xi’an Key Laboratory of Textile Chemical Engineering AuxiliariesXi’an Polytechnic UniversityXi’an 710048China school of physics and information Technology Shaanxi Normal UniversityXi’an 710062China

The strong pyrocatalytic dye decomposition of the BaTiO_(3)/Pr_(2)O_(3) heterojunction catalyst under cold–hot alternation conditions has been demonstrated in this *** pure BaTiO_(3) nanofibers,~54%rhodamine B(RhB)dye is decomposed under the cold–hot alternation of 29–57℃.With the loading content of Pr_(2)O_(3) increases from 0 to 4 wt%,the pyrocatalytic decomposition ratio of RhB solution increases first and then decreases,eventually achieving a maximum of 91%at 3 wt%.The enhanced pyrocatalytic performance after loading Pr_(2)O_(3) can be attributed to an internal electric field of the heterojunction,which effectively separates positive and negative *** strongly pyrocatalytic performance of BaTiO_(3)/Pr_(2)O_(3) makes it hopeful for applications in the dye wastewater treatment through harvesting the environmental cold–hot temperature alternation thermal energy in future.

关键词： pyroelectric materials BaTiO_(3) pyrocatalysis BaTiO_(3)/Pr_(2)O_(3)heterojunction dye decomposition