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Color Image Compression and Encryption Algorithm Based on 2D Compressed Sensing and Hyperchaotic System

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Computers, Materials & Continua 2024年第2期78卷 1977-1993页

作者： Zhiqing dong Zhao Zhang Hongyan zhou Xuebo Chen School of Computer Science and Software Engineering University of Science and Technology LiaoningAnshan114051China School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051China

With the advent of the information security era,it is necessary to guarantee the privacy,accuracy,and dependable transfer of *** study presents a new approach to the encryption and compression of color *** is predicated on 2D compressed sensing(CS)and the hyperchaotic ***,an optimized Arnold scrambling algorithm is applied to the initial color images to ensure strong ***,the processed images are con-currently encrypted and compressed using 2D *** them,chaotic sequences replace traditional random measurement matrices to increase the system’s ***,the processed images are re-encrypted using a combination of permutation and diffusion *** addition,the 2D projected gradient with an embedding decryption(2DPG-ED)algorithm is used to reconstruct *** with the traditional reconstruction algorithm,the 2DPG-ED algorithm can improve security and reduce computational ***,it has better *** experimental outcome and the performance analysis indicate that this algorithm can withstand malicious attacks and prove the method is effective.

关键词： Image encryption image compression hyperchaotic system compressed sensing

Reflective ultrathin light-sheet microscopy with isotropic 3D resolutions

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Photonics Research 2024年第2期12卷 271-281页

作者： YUE WANG DASHAN dong WENKAI YANG RENXI HE MING LEI KEBIN shi State Key Laboratory for Mesoscopic Physics Department of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of Membrane Biology School of Life Sciencesand Biomedical Pioneering Innovation Center(BIOPIC)Peking UniversityBeijing 100871China School of Physics Xi’an Jiaotong UniversityXi’an 710049China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China

Light-sheet fluorescence microscopy(LSFM)has played an important role in bio-imaging due to its advantages of high photon efficiency,fast speed,and long-term imaging *** perpendicular layout between LSFM excitation and detection often limits the 3D resolutions as well as their ***,we report on a reflective type light-sheet microscope with a mini-prism used as an optical path *** conventional high NA objectives can be used both in excitation and detection with this *** resolutions in 3D down to300 nm could be achieved without *** proposed method also enables easy transform of a conventional fluorescence microscope to high performance light-sheet microscopy.

关键词： resolution excitation light

Recent progress and strategies of cathodes toward polysulfides shuttle restriction for lithium-sulfur batteries

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Rare Metals 2024年第9期43卷 4132-4161页

作者： Xing-You Rao Shuang-Fei Xiang Jian zhou Zhen Zhang Xiang-Yu Xu Yuan-Yuan Xu Xin-Chi zhou Zheng-Dao Pan Su-Chong Tan shi-Xing dong zhou-Lu Wang Yu-Tong Wu Yun-Lei zhou Xiang Liu Yi Zhang Shan Jiang School of Energy Sciences and Engineering Nanjing Tech University School of Materials Science and Engineering and Institute of Smart Fiber Materials Zhejiang Sci-Tech University JiangSu Sailboat Petrochemical Co. Ltd Hangzhou Institute of Technology Xidian University

Lithium-sulfur batteries(LSBs) have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density, low cost, and environmental friendliness. However, the development and commercialization path of LSBs still presents significant limitations and challenges, particularly the notorious shuttle effect triggered by soluble longchain lithium polysulfides(LiPSs), which inevitably leads to low utilization of cathode active sulfur and high battery capacity degradation, short cycle life, etc. Substantial research efforts have been conducted to develop various sulfur host materials capable of effectively restricting the shuttle effect. This review firstly introduces the fundamental electrochemical aspects of LSBs, followed by a comprehensive analysis of the mechanism underlying the shuttle effect in Li–S batteries and its profound influence on various battery components as well as the overall battery performance. Subsequently, recent advances and strategies are systematically reviewed, including physical confinement, chemisorption, and catalytic conversion of sulfur hosts for restricting LiPSs shuttle effects. The interplay mechanisms of sulfur hosts and LiPSs are discussed in detail and the structural advantages of different host materials are highlighted. Furthermore, key insights for the rational design of advanced host materials for LSBs are provided, and the upcoming challenges and the prospects for sulfur host materials in lithium-sulfur batteries are also explored.

关键词： Host Lithium-sulfur batteries Polysulfides Shuttle effect

An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan Qiu Jia Li dong Feng shi-Ming Wei Gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow

A tree-growing graphic model for asymmetrical phantom networks in polymeric gels undergoing dynamic mechanochemical coupling

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Science China(Technological Sciences) 2024年第2期67卷 558-567页

作者： shi WeiLin zhou Jian LU HaiBao ELMARAKBI Ahmed FU Yong-Qing National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Faculty of Engineering and Environment University of NorthumbriaNewcastle upon Tyne NEI 8STUK

Network structures of various polymers have significant effects on their mechanical properties;therefore,numerous studies have investigated the constitutive relationship between symmetrical network structures and their rubber elasticity in ***,few studies have focused on asymmetrical network structures in polymers that undergo bond exchange reactions,selfassembly,or mechanochemical coupling—all of which are induced by transition probabilities of chemical bonding *** this study,an extended constraint junction and phantom network model is formulated using the tree-growing theory to establish a constitutive relationship between asymmetrical network structures and their rubber elasticity in polymers.A free-energy equation is further developed to explore working principles of configurational transitions on the dynamic rubber elasticity of symmetrical and asymmetrical network *** constitutive relationship between dynamic rubber elasticity and symmetrical and asymmetrical network structures has also been proposed for the gels undergoing mechanochemical and hydromechanical ***,the effectiveness of this newly proposed tree-growing model has been verified by comparing with the classical affine network model,finite element analysis,and the experimental results of gels reported in literature.

关键词： gel polymer network rubber elasticity asymmetric

The roles of RACK1 in the pathogenesis of Alzheimer's disease

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Journal of Biomedical Research 2024年第2期38卷 137-148页

作者： Wenting He Xiuyu shi Zhifang dong Pediatric Research Institute Ministry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChongqing Key Laboratory of Child Neurodevelopment and Cognitive DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China

The receptor for activated C kinase 1(RACK1)is a protein that plays a crucial role in various signaling pathways and is involved in the pathogenesis of Alzheimer's disease(AD),a prevalent neurodegenerative ***1 is highly expressed in neuronal cells of the central nervous system and regulates the pathogenesis of ***,RACK1 is involved in regulation of the amyloid-β precursor protein processing through α-or β-secretase by binding to different protein kinase C ***,RACK1 promotes synaptogenesis and synaptic plasticity by inhibiting N-methyl-D-aspartate receptors and activating gamma-aminobutyric acid A receptors,thereby preventing neuronal ***1 also assembles inflammasomes that are involved in various neuroinflammatory pathways,such as nuclear factor-kappa B,tumor necrosis factor-alpha,and NOD-like receptor family pyrin domain-containing 3 *** potential to design therapeutics that block amyloid-β accumulation and inflammation or precisely regulate synaptic plasticity represents an attractive therapeutic strategy,in which RACK1 is a potential *** this review,we summarize the contribution of RACK1 to the pathogenesis of AD and its potential as a therapeutic target.

关键词： RACK1 Alzheimer's disease PKC amyloid-β synaptic plasticity neuroinflammation

Mastering air combat game with deep reinforcement learning

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Defence Technology（防务技术） 2024年第4期34卷 295-312页

作者： Jingyu Zhu Minchi Kuang Wenqing zhou Heng shi Jihong Zhu Xu Han Department of Precision Instruments Tsinghua UniversityBeijing 100084China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Chengdu Aircraft Design&Research Institute Aviation Industry Corporation of ChinaChengdu 610000China

Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural *** loss is the difficulty of learning new knowledge after the network has *** this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning *** motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a ***,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be *** addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an *** the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions *** the interruption mechanism can significantly improve the performance of the *** simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data *** experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper.

关键词： Air combat MCLDPPO Interruption mechanism Digital twin Distributed system

High-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method

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Defence Technology（防务技术） 2024年第2期32卷 209-221页

作者： Mingming Wang Linfang Qian Guangsong Chen Tong Lin Junfei shi shijie zhou Nanjing University of Science and Technology Nanjing 210094JiangsuChina Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099ShaanxiChina Nanjing Vocational University of Industry Technology Nanjing 210023JiangsuChina

This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted ***,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the ***,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test ***,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile *** engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is *** results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle.

关键词： Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method

Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research International 2024年第3期31卷 710-718页

作者： Yan-hui Hou Ze-kun Xu shi-long zhou Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation