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波动误差量化辅助的改进Cascade协议

国防科技大学学报 2025年第1期47卷 158-167页

作者：周壮骆俊杉谢顺钦陈宇豪王世练国防科技大学电子科学学院湖南长沙410073 中国工程物理研究院电子工程研究所四川绵阳621999

针对经典的Cascade协议协商效率低、容易造成密钥泄露的问题,提出波动误差量化辅助的改进Cascade协议。在信息协商之前,分析合法节点的信道幅度特征波动差异的统计特征,利用统计特性提出了一种波动误差量化方法。基于所提量化方法,采用... 详细信息

针对经典的Cascade协议协商效率低、容易造成密钥泄露的问题,提出波动误差量化辅助的改进Cascade协议。在信息协商之前,分析合法节点的信道幅度特征波动差异的统计特征,利用统计特性提出了一种波动误差量化方法。基于所提量化方法,采用奇偶分组和分块协商的方式设计了一种改进的Cascade协议。仿真结果表明,所提改进Cascade协议以牺牲部分的协商成功率为代价有效提升了协商协议的协商效率,降低了信息协商所需的计算复杂度和密钥信息泄露的可能性。此外,与现有密钥生成方案相比,基于所提改进的Cascade协议的密钥生成方案具有较低的密钥不一致率和较高的密钥生成速率。

关键词：物理层安全密钥生成信息协商协商效率

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ZTA15钛合金铸件铸态相组成分布预测

特种铸造及有色合金 2025年第1期45卷 123-129页

作者：邹鑫锐廖敦明陈宇豪尹昊纪志军张健辉华中科技大学材料科学与工程学院武汉430074 中国航发北京航空材料研究院北京100095

基于铸造过程数值模拟温度场以及钛合金相成分凝固冷却数据库,建立了ZTA15钛合金铸件铸态相成分分布预测模型。并在实际ZTA15薄壁骨架浇注件上选取多个位置进行金相观察,借助Image-Pro Plus 6.0图形分析软件统计各位置的α相含量,并与... 详细信息

基于铸造过程数值模拟温度场以及钛合金相成分凝固冷却数据库,建立了ZTA15钛合金铸件铸态相成分分布预测模型。并在实际ZTA15薄壁骨架浇注件上选取多个位置进行金相观察,借助Image-Pro Plus 6.0图形分析软件统计各位置的α相含量,并与数值模拟结果进行对比分析,验证了数值模拟结果的准确性。

关键词：钛合金精密铸造相成分分布

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基于核密度估计的土壤样本代表性修正研究

华中农业大学学报 2025年第1期44卷 94-104页

作者：李坤陈宇昊李文岳王子影傅佩红黄魏华中农业大学资源与环境学院武汉430070

为充分利用历史样点数据获取更可靠的土壤-环境知识,进而获取更高精度的土壤预测推理图,采用样本代表性修正方法获取更高的知识精度,利用样本空间与总体空间环境协变量的空间相似度关系,以核密度估计为基础,采用3种不同算法对每个土壤... 详细信息

为充分利用历史样点数据获取更可靠的土壤-环境知识,进而获取更高精度的土壤预测推理图,采用样本代表性修正方法获取更高的知识精度,利用样本空间与总体空间环境协变量的空间相似度关系,以核密度估计为基础,采用3种不同算法对每个土壤采样点探寻最优权重,并以土壤表层有机质含量预测制图为例验证方法的科学性和有效性。结果显示,该修正方法最高可将多元线性回归制图的RMSE和MAE分别降低10.30%和12.74%,证实了该方法的可行性与有效性。

关键词：环境协变量空间偏差修正样本代表性启发式算法数字土壤制图历史样点

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Ameliorating the Strength-Modulus Synergy in GNPs Reinforced Mg-Zn-Zr Composites via Multidirectional Forging and Hot Extrusion Deformation

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 425-437页

作者： yuhao chen Kaibo Nie Kunkun Deng Zhilong Liu Quanxin Shi College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Compressor Technology(Compressor Technology Laboratory of Anhui Province) Hefei 230031China Instrumental Analysis Center Taiyuan University of TechnologyTaiyuan 030024China

The integration of lightweight and high-modulus magnesium-based materials is becoming increasingly valued as structural materials due to the complexity and intelligence of industrial products like automobiles and *** this study,the graphene nanoplatelets(GNPs)/Mg-Zn-Zr composites with 0.5 wt%GNPs were successfully prepared by the combination of multidirectional forging(MDF)and hot extrusion(Ex).The newly-developed composites after multi-step deformation possessed excellent strength and modulus,with a tensile strength exceeding 375 MPa and an elastic modulus reaching 54 *** results revealed that the stripping and thinning of GNPs bands parallel to the extrusion direction occurred after MDF+Ex,which promoted the dynamic recrystallization and the formation of numerous fine *** significant improvement in comprehensive mechanical performances of the composites could be primarily ascribed to the refinement of grain size caused by the optimized distribution of GNPs,and efficient load transfer facilitated by the tight interface.

关键词： Magnesium matrix composites Graphene nanoplatelets(GNPs) Multi-step deformation Microstructure Strength-modulus

Continuous-Time Channel Prediction Based on Tensor Neural Ordinary Differential Equation

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China Communications 2024年第1期21卷 163-174页

作者： Mingyao Cui Hao Jiang yuhao chen Yang Du Linglong Dai The Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Huawei Technology Co. Ltd.Chengdu Research InstituteChengdu 611730China

Channel prediction is critical to address the channel aging issue in mobile *** channel prediction techniques are mainly designed for discrete channel prediction,which can only predict the future channel in a fixed time slot per frame,while the other intra-frame channels are usually recovered by ***,these approaches suffer from a serious interpolation loss,especially for mobile millimeter-wave *** solve this challenging problem,we propose a tensor neural ordinary differential equation(TN-ODE)based continuous-time channel prediction scheme to realize the direct prediction of intra-frame ***,inspired by the recently developed continuous mapping model named neural ODE in the field of machine learning,we first utilize the neural ODE model to predict future continuous-time *** improve the channel prediction accuracy and reduce computational complexity,we then propose the TN-ODE scheme to learn the structural characteristics of the high-dimensional channel by low-dimensional learnable *** results show that the proposed scheme is able to achieve higher intra-frame channel prediction accuracy than existing schemes.

关键词： channel prediction massive multipleinput-multiple-output millimeter-wave communications ordinary differential equation

Components and Anisotropy of 3D QFP Waves During the Early Solar Eruption

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Research in Astronomy and Astrophysics 2024年第12期24卷 105-115页

作者： Jialiang Hu Jing Ye yuhao chen Zhixing Mei Shanshan Xu Jun Lin Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Yunnan Province China–Malaysia HF-VHF Advanced Radio Astronomy Technology International Joint Laboratory Kunming 650216China

The propagation of disturbances in the solar atmosphere is inherently three-dimensional(3D), yet comprehensive studies on the spatial structure and dynamics of 3D wave fronts are scarce. Here we conduct high-resolution 3D numerical simulations to investigate filament eruptions, focusing particularly on the 3D structure and genesis of extreme ultraviolet(EUV) waves. Our results demonstrate that the EUV wave front forms a dome-like configuration subdivided into three distinct zones. The foremost zone, preceding the flux rope, consists of fastmode shock waves that heat the adjacent plasma. Adjacent to either side of the flux rope, the second zone contains expansion waves that cool the nearby plasma. The third zone, at the juncture of the first two, exhibits minimal disturbances. This anisotropic structure of the wave front stems from the configuration and dynamics of the flux rope, which acts as a 3D piston during eruptions—compressing the plasma ahead to generate fast-mode shocks and evacuating the plasma behind to induce expansion waves. This dynamic results in the observed anisotropic wave front. Additionally, with synthetic EUV images from simulation data, the EUV waves are observable in Atmospheric Imaging Assembly 193 and 211 ?, which are identified as the fast-mode shocks. The detection of EUV waves varies with the observational perspective: the face-on view reveals EUV waves from the lower to the higher corona, whereas an edge-on view uncovers these waves only in the higher corona.

关键词： Sun corona-Sun coronal mass ejections(CMEs)-shock waves

Near-field wideband beam training for ELAA with uniform circular array

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Science China(Information Sciences) 2024年第6期67卷 370-383页

作者： yuhao chen Linglong DAI Department of Electronic Engineering Tsinghua UniversityBeijing National Research Center for Information Science and Technology (BNRist)

Extremely large-scale antenna array(ELAA) at millimeter wave(mmWave) and Terahertz(THz)band has been considered a key technology for combating high attenuation in high-frequency bands in future6G communications. Uniform circular arrays(UCAs) have attracted much attention because of their ability to provide flat beamforming gain at all angles. To realize efficient beamforming, beam training is widely used to acquire channel state information. However, with a large antenna number, the beam training overhead in ELAA systems becomes overwhelming. Moreover, with a large bandwidth, the beam defocus effect severely degrades beam training accuracy. To address these issues, this paper proposes a frequency-dependent focusing(FDF)-based beam training scheme to realize effective beam training in near-field wideband ELAA systems with UCA. Specifically, we first analyze the FDF property of UCA, where signals at different subcarriers can simultaneously focus on different distances. Then, by exploiting the FDF property to search different distances using different subcarriers simultaneously, we design a hierarchical codebook and propose an FDFbased beam training scheme. To reveal the effectiveness of the proposed scheme, we compare its necessary beam training overhead with that of existing schemes. Finally, the simulation results demonstrate that the proposed scheme can achieve accurate beam training in near-field wideband UCA systems with a low beam training overhead.

关键词： extremely large-scale antenna array (ELAA) uniform circular array (UCA) near-field wideband beam training

Spatiotemporal evolution of Ediacaran-Cambrian(ca.551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年第2期68卷 549-563页

作者： Yan YE Lei ZHANG Can chen Shan CHANG yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Science China University of GeosciencesWuhan 430074China Department of Geology Lund UniversityLund 22362Sweden Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China Second Geological Brigade of Hubei Geological Bureau Enshi 445000China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China Exploration and Development Research Institute SINOPEC Jianghan Oilfield CompanyWuhan 430223China

The origin and evolution of sponges have attracted interest,not only because they are among the most basal metazoans,but also because they act as important ecological engineers in the *** research suggested that sponge groups diversified quickly during the Cambrian Series 2,while Terreneuvian sponge fossils are conspicuously rare and poorly ***,an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C,ca.551–523 Ma)transitional carbonates/cherts worldwide,particularly in South China,which calls for updated *** oxygenation has been widely proposed to play a critical role in organismal evolution,but its relationship with sponges is unclear and falls into a“chicken-egg”*** this study,we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous *** to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area,and then potentially expand to the continental shelf and deep basin in the lower *** these sections,the abundance,size,and diversity of monaxons increase upwards,followed by the appearance of diaxons,triaxons and then *** the uncertain affinity of the sponge fossils,it is possible that siliceous hexactinellids evolved later than siliceous demosponges,given that the earliest spicule assemblages are exclusively composed of monaxons,which commonly form bundles comparable to modern *** geochemical data from the Sifangjing section,Guizhou Province and the Yanziqiao section,Hunan Province,South China show that the appearance of sponges usually corresponds to anoxic *** addition,we applied the recently proposed Biological Pump,Oxygen and Phosphorus(BPOP)model to trace the evolution of oceanic oxygen concentrations with the radiation of *** results indicate that the possible contribution o

关键词： Cambrian Sponge Oxygenation Silicon concentration Box model

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百年来中国净土宗研究述评

宗教学研究 2019年第1期 129-137页

作者：陈昱昊武汉大学文学院

百年来中国净土宗研究分为四个时期,分别是民国、中华人民共和国成立后至改革开放之前、20世纪最后20年以及21世纪。其研究内容可分为史学研究、理论研究、文学研究和艺术研究四个方面。史学研究和理论研究成果较为丰硕,文学研究亦取得... 详细信息

百年来中国净土宗研究分为四个时期,分别是民国、中华人民共和国成立后至改革开放之前、20世纪最后20年以及21世纪。其研究内容可分为史学研究、理论研究、文学研究和艺术研究四个方面。史学研究和理论研究成果较为丰硕,文学研究亦取得了一定成绩,艺术研究最为薄弱。但总体而言,净土宗研究的现有成绩与其历史影响极为不符,有待研究的空间巨大。

关键词：净土宗史学研究理论研究文学研究艺术研究