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A Dual Domain Robust Reversible Watermarking Algorithm for Frame Grouping Videos Using Scene Smoothness

Computers, Materials & Continua 2024年第6期79卷 5143-5174页

作者： Yucheng liang Ke Niu Yingnan zhang Yifei Meng College of Cryptographic Engineering Engineering University of the Chinese People’s Armed Police ForceXi’an710086China Key Laboratory of Information Security of the Chinese People’s Armed Police Force Engineering University of the Chinese People’s Armed Police ForceXi’an710086China

The proposed robust reversible watermarking algorithm addresses the compatibility challenges between robustness and reversibility in existing video watermarking techniques by leveraging scene smoothness for frame grouping *** in the H.264 video coding standard,the algorithm first employs traditional robust watermark stitching technology to embed watermark information in the low-frequency coefficient domain of the U ***,it utilizes histogram migration techniques in the high-frequency coefficient domain of the U channel to embed auxiliary information,enabling successful watermark extraction and lossless recovery of the original video *** results demonstrate the algorithm’s strong imperceptibility,with each embedded frame in the experimental videos achieving a mean peak signal-to-noise ratio of 49.3830 dB and a mean structural similarity of *** with the three comparison algorithms,the performance of the two experimental indexes is improved by 7.59%and 0.4%on *** the same time,the proposed algorithm has strong robustness to both offline and online attacks:In the face of offline attacks,the average normalized correlation coefficient between the extracted watermark and the original watermark is 0.9989,and the average bit error rate is *** the face of online attacks,the normalized correlation coefficient between the extracted watermark and the original watermark is 0.8840,and the mean bit error rate is *** with the three comparison algorithms,the performance of the two experimental indexes is improved by 1.27%and 18.16%on average,highlighting the algorithm’s ***,the algorithm exhibits low computational complexity,with the mean encoding and the mean decoding time differentials during experimental video processing being 3.934 and 2.273 s,respectively,underscoring its practical utility.

关键词： Robust reversible watermarking scene smoothness dual-domain U channel H.264 encoding standard

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Statistical QoS Provisioning Architecture for 6G Satellite-Terrestrial Integrated Networks

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Journal of Communications and Information Networks 2024年第1期9卷 34-42页

作者： Jingqing Wang Wenchi Cheng Wei zhang Hui liang School of Telecommunications Engineering Xidian UniversityXi’an 710071China School of Electrical Engineering and Telecommunications the University of New South WalesSydneyAustralia School of Electrical Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China Peng Cheng Laboratory Shenzhen 518055China.

The emergence of massive ultra-reliable and low latency communications (mURLLC) as a category of age/time/reliability-sensitive service over 6G wireless networks has received considerable research attention, which has presented unprecedented challenges. As one of the key enablers for 6G,satellite-terrestrial integrated networks (STIN) have been developed to offer more expansive connectivity and comprehensive 3D coverage in space-aerial-terrestrial domains for supporting 6G mission-critical mURLLC applications while fulfilling diverse and rigorous quality of service (QoS) requirements. In the context of these mURLLC-driven satellite services, data freshness assumes paramount importance, as outdated data may engender unpredictable or catastrophic *** effectively measure data freshness in satellite-terrestrial integrated communications,age of information(AoI)has recently surfaced as a new dimension of QoS metric to support time-sensitive applications. It is crucial to design new analytical models that ensure stringent and diverse QoS metrics bounded by different key parameters,including AoI,delay,and reliability,over 6G satellite-terrestrial integrated networks. However,due to the complicated and dynamic nature of satellite-terrestrial integrated network environments, the research on efficiently defining new statistical QoS provisioning schemes while taking into account varying degrees of freedom has still been in their infancy. To remedy these deficiencies, in this paper we develop statistical QoS provisioning schemes over 6G satellite-terrestrial integrated networks in the finite blocklength regime. Particularly, we firstly introduce and review key technologies for supporting ***,we formulate a number of novel fundamental statistical-QoS metrics in the finite blocklength ***,we conduct a set of simulations to validate and evaluate our developed statistical QoS provisioning schemes over satellite-terrestrial integrated networks.

关键词： statistical QoS provisioning mURLLC peak AoI satellite-terrestrial integrated networks QoS exponents hybrid automatic repeat request finite blocklength coding

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Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： Xue zhang Ya-hang Mu liang Ma Jing-jing liang Yi-zhou Zhou Xiao-feng Sun Jin-guo Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

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Therapeutic potential of targeting protein tyrosine phosphatases in liver diseases

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3295-3311页

作者： Ao Wang Yi zhang Xinting Lv Guang liang Department of Pharmacy and Institute of Inflammation Zhejiang Provincial Affiliated People’s HospitalHangzhou Medical CollegeHangzhou 310014China Key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationYanbian UniversityYanji 133002China Chemical Biology Research Center School of Pharmaceutical SciencesWenzhou Medical UniversityWenzhou 325035China

Protein tyrosine phosphorylation is a post-translational modification that regulates protein structure to modulate demic organisms’homeostasis and *** physiological process is regulated by two enzyme families,protein tyrosine kinases(PTKs)and protein tyrosine phosphatases(PTPs).As an important regulator of protein function,PTPs are indispensable for maintaining cell intrinsic physiology in different systems,as well as liver physiological and pathological *** of PTPs has been implicated in multiple liver-related diseases,including chronic liver diseases(CLDs),hepatocellular carcinoma(HCC),and liver injury,and several PTPs are being studied as drug therapeutic ***,given the regulatory role of PTPs in diverse liver diseases,a collated review of their function and mechanism is ***,based on the current research status of targeted therapy,we emphasize the inclusion of several PTP members that are clinically significant in the development and progression of liver *** an emerging breakthrough direction in the treatment of liver diseases,this review summarizes the research status of PTP-targeting compounds in liver diseases to illustrate their potential in clinical ***,this review aims to support the development of novel PTP-based treatment pathways for liver diseases.

关键词： Tyrosine phosphorylation PTPs Signal transduction CLDs HCC Allosteric inhibitor PROTACs Drug development

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Resource Allocation for Space-Air-Ground Integrated Networks:A Comprehensive Review

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Journal of Communications and Information Networks 2024年第1期9卷 1-23页

作者： Hui liang Zhiqing Yang Guobin zhang Hanxu Hou School of Electrical Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China Peng Cheng Laboratory Shenzhen 518055China School of Electronics and Information Engineering Shenzhen UniversityShenzhen 518061China School of Electrical Engineering and Intelligentization Dongguan University of TechonologyDongguan 523808China School of Information and Communication Engineering Guangzhou Maritime UniversityGuangzhou 510725China

The space-air-ground integrated networks (SAGIN) has emerged as a critical paradigm to address the growing demands for global connectivity and enhanced communication services. This paper gives a thorough review of the strategies and methodologies for resource allocation within SAGIN, focusing on the challenges and solutions within its complex structure. With the advent of technologies such as 6G, the dynamics of resource optimization have become increasingly complex, necessitating innovative approaches for efficient management. We examine the application of mathematical optimization, game theory, artificial intelligence (AI), and dynamic optimization techniques in SAGIN,offering insights into their effectiveness in ensuring optimal resource distribution, minimizing delays, and maximizing network throughput and stability. The survey highlights the significant advances in AI-based methods,particularly deep learning and reinforcement learning, in tackling the inherent challenges of SAGIN resource allocation. Through a critical review of existing literature, this paper categorizes various resource allocation strategies, identifies current research gaps, and discusses potential future directions. Our findings highlight the crucial role of integrated and intelligent resource allocation mechanisms in realizing the full potential of SAGIN for next-generation communication networks.

关键词： space-air-ground integrated networks resource allocation 6G optimization theory game theory artificial intelligence

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Experimental study on the effect of flexible joints of a deep-buried tunnel across an active fault under high in-situ stress conditions

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Underground Space 2024年第6期19卷 189-207页

作者： Jiawei zhang Zhen Cui Qian Sheng Wanhua Zhao liang Song State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan 430023China

During dislocation,a tunnel crossing the active fault will be damaged to varying degrees due to its permanent stratum *** previous studies did not consider the influence of the tunnel’s deep burial and the high in-situ stress,so the results were not entirely *** this paper,the necessity of solving the anti-dislocation problem of deep-buried tunnels is systemically *** the model test of tunnels across active faults,the differences in failures between deep-buried tunnels and shallow-buried tunnels were compared,and the dislocation test of deep-buried segmental tunnels was carried out to analyze the external stress change,lining strain,and failure mode of *** results are as follows.(1)The overall deformation of deep-buried and shallow-buried tunnels is both *** failure mode of deep-buried tunnels is primarily characterized by shear and tensile failure,resulting in significant compressive deformation and a larger damaged *** contrast,shallow-buried tunnels mainly experience shear failure,with the tunnel being sheared apart at the fault crossing,leading to more severe damage.(2)After the segmental structure design of the deep-buried tunnel,the‘‘S”deformation pattern is transformed into a‘‘ladder”pattern,and the strain of the tunnel and the peak stress of the external rock mass are reduced;therefore,damages are significantly mitigated.(3)Through the analysis of the distribution of cracks in the tunnel lining,it is found that the tunnel without a segmental structure design has suffered from penetrating failure and that cracks affect the entire *** cracks in a flexible segmental tunnel affect about 66.6%of the entire length of the tunnel,and cracks in a tunnel with a short segmental tunnel only affect about 33.3%of the entire length of the ***,a deep-buried tunnel with a short segmental tunnel can yield a better anti-dislocation effect.(4)By comparing the shallow-buried segmental tunnel in previous

关键词： Tunnel project Crossing active fault High in-situ stress Segmental structure design Flexible joint

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Formation and transformation of metastable LPSO building blocks clusters in Mg-Gd-Y-Zn-Zr alloys by spinodal decomposition and heterogeneous nucleation

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Journal of Magnesium and Alloys 2024年第2期12卷 673-686页

作者： Xin Zhao Zhong Yang Jiachen zhang Minxian liang Liying Wang School of Materials Science and Chemical Engineering Xi’an Technological UniversityXi’an 710021China Xi’an Tianli Metal Composite Material Co.Ltd. Xi’an 710299China

To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)structures in the Mg-Gd-Y-Zn-Zr alloy annealed at 300℃~500℃.Various types of metastable LPSO building block clusters were found to exist in alloy structures at different temperatures,which precipitate during the solidification and homogenization *** stability of Zn/Y clusters is explained by the first principles of density functional *** LPSO structure is distinguished by the arrangement of its different Zn/Y enriched LPSO structural units,which comprises local fcc stacking sequences upon a tightly packed *** presence of solute atoms causes local lattice distortion,thereby enabling the rearrangement of Mg atoms in the different configurations in the local lattice,and local HCP-FCC transitions occur between Mg and Zn atoms occupying the nearest neighbor *** finding indicates that LPSO structures can generate necessary Schockley partial dislocations on specific slip surfaces,providing direct evidence of the transition from 18R to *** of the LPSO,devoid of any defects and non-coherent interfaces,was observed separately from other precipitated *** a result,the precipitation sequence of LPSO in the solidification stage was as follows:Zn/Ycluster+Mg layers→various metastable LPSO building block clusters→18R/24R LPSO;whereas the precipitation sequence of LPSO during homogenization treatment was observed to be as follows:18R LPSO→various metastable LPSO building block clusters→14H *** these,14H LPSO was found to be the most thermodynamically stable structure.

关键词： LPSO Spinodal decomposition Homogenization treatment Clusters Phase transformation

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Energy release characteristics of PTFE/Al/TiH_(2) reactive jet with different TiH_2 content

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Defence Technology（防务技术） 2024年第9期39卷 168-176页

作者： Chunlan Jiang Jingbo zhang Rong Hu liang Mao Ming Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH_(2) reactive liners with different TiH_(2) content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH_(2) reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time,pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH_(2) jet initially increase and then decrease with increasing TiH_(2) content. When the TiH_(2) content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH_(2) content increased from 0% to 30%. Finally,combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH_(2) on energy release of the reactive jet is expounded.

关键词： PTFE/Al/TiH_(2) Reactive materials Shaped charge Impact energy release characteristics

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High-performance terahertz modulators induced by substrate field in Te-based all-2D heterojunctions

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Light(Science & Applications) 2024年第3期13卷 577-586页

作者： Pujing zhang Qihang liang Qingli Zhou Jinyu Chen Menglei Li Yuwang Deng Wanlin liang liangliang zhang Qinghua zhang Lin Gu Chen Ge Kui-juan Jin Cunlin zhang Guozhen Yang Department of Physics Key Laboratory of Terahertz OptoelectronicsMinistry of Educationand Beijing Advanced Innovation Center for Imaging Theory and TechnologyCapital Normal UniversityBeijing 100048China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Department of Materials Science and Engineering Beijing National Center for Electron Microscopy and Laboratory of Advanced MaterialsTsinghua UniversityBeijing 100084China

High-performance active terahertz modulators as the indispensable core components are of great importance for the next generation communication ***,they currently suffer from the tradeoff between modulation depth and ***,we introduce two-dimensional(2D)tellurium(Te)nanofilms with the unique structure as a new class of optically controlled terahertz modulators and demonstrate their integrated heterojunctions can successfully improve the device performances to the optimal and applicable levels among the existing all-2D broadband *** photoresponse measurements confirm the significant impact of the stacking *** first clarify the direction of the substrate-induced electric field through first-principles calculations and uncover the unusual interaction mechanism in the photoexcited carrier dynamics associated with the charge transfer and interlayer exciton *** advances the fundamental and applicative research of Te nanomaterials in high-performance terahertz optoelectronics.

关键词： performance field terahertz

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Gut flora in multiple sclerosis:implications for pathogenesis and treatment

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Neural Regeneration Research 2024年第7期19卷 1480-1488页

作者： Weiwei zhang Ying Wang Mingqin Zhu Kangding Liu Hong-liang zhang Department of Neurology the First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina Department of Life Sciences National Natural Science Foundation of ChinaBeijingChina

Multiple sclerosis is an inflammatory disorder chara cterized by inflammation,demyelination,and neurodegeneration in the central nervous *** current first-line therapies can help manage symptoms and slow down disease progression,there is no cure for multiple *** gut-brain axis refers to complex communications between the gut flo ra and the immune,nervous,and endocrine systems,which bridges the functions of the gut and the *** in the gut flora,termed dys biosis,can lead to systemic inflammation,leaky gut syndrome,and increased susceptibility to *** pathogenesis of multiple sclerosis involves a combination of genetic and environmental factors,and gut flora may play a pivotal role in regulating immune responses related to multiple scle *** develop more effective therapies for multiple scle rosis,we should further uncover the disease processes involved in multiple sclerosis and gain a better understanding of the gut-brain *** review provides an overview of the role of the gut flora in multiple scle rosis.

关键词： gut flora gut-brain axis multiple sclerosis pathogenesis treatment

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