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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 10-14页

作者： liu Hai-tao han Fang-jing WAN Jian-wei School DSP Group of National University of Defense Technology Changsha 410073 P.R. China

Information integrity is key to successful operations in intricacy environments in the future, especially when strong interferences exist. This paper presents the design of a novel wireless packet network receiver system for Low Earth Orbit （LEO） micro-satellites with adaptive nulling antenna arrays. It uses three types of interference suppression in cascade： namely spread spectrum, adaptive array nulling, and transform domain filtering. This paper proposes a pilot channel-aided method in order to make full advantage of this arrangement, and analyzes its throughput and delay performance using the Markov chain model. Our results show that this method can achieve excellent delay and throughput performance： When the number of array antenna is 8, its throughput increase relative to the standard Slot-ALOHA protocol is 125 96.

关键词： LEO adaptive array ALOHA packet radio networks

Simulation of hard–soft material interaction under impact loading employing the material point method

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Science China(Technological Sciences) 2015年第4期58卷 763-768页

作者： liu han tao JIANG Shan CHEN Zhen GAN Yong ChanG Jian Zhong WANG Yan Hua TONG Zhi Hui Laboratory of Energy & Environment and Computational Fluid Dynamics North University of China Department of Civil and Environmental Engineering University of Missouri School of Aeronautics and Astronautics Zhejiang University

Understanding the mechanisms of hard–soft material interaction under impact loading is important not only in the defense industry but also in daily ***,traditional mesh-based spatial discretization methods that are time consuming owing to the need for frequent re-meshing,such as the finite element method and finite difference method,can hardly handle large deformation involving failure evolution in a multi-phase interaction *** objective of this research is to develop a quasi-meshless particle method based on the material point method for the model-based simulation of the hard–soft material interaction *** demonstrate the proposed procedure,scenarios of a hard–soft material impact test are considered,where a force is applied to layers of materials and a hard bar with an initial velocity impacts a target with layers of different *** stress wave propagation and resulting failure evolution are simulated and compared with available *** research tasks are then discussed on the basis of the preliminary results.

关键词： material point method hard--soft materials impact quasi-meshless particle method

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng tao Shujun han Huici WU Kai YANG Zhu han National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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CAF-derived exosome-miR-3124-5p promotes malignant biological processes in NSCLC via the TOLLIP/TLR4-MyD88-NF-κB pathway

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Oncology Research 2025年第1期33卷 133-148页

作者： tao SUN QINGHUA SONG HUA liu Department of Respiratory and Critical Care Medicine Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong226001China Department of Emergency The People’s Hospital of RugaoNantong226500China Department of Haematology The People’s Hospital of RugaoNantong226500China

Background:Lung cancer is a life-threatening disease that occurs worldwide,but is especially common in *** crucial role of the tumour microenvironment(TME)in non-small cell lung cancer(NSCLC)has attracted recent ***-associated fibroblasts(CAFs)are the main factors that contribute to the TME function,and CAF exosomes are closely linked to ***:The expression levels of miR-3124-5p and Toll-interacting protein(TOLLIP)were analysed by bioinformatics prediction combined with RT-qPCR/Western Blot *** were isolated and identified from clinical NSCLC *** electron microscopy and Western Blot were used to identify exosomes from these *** in proliferation(CCK-8 and clone formation),migration(wound healing),and invasion(transwell)of NSCLC cells were *** Luciferase reporter test was applied to clarify the binding of miR-3124-5p to *** TOLLIP/TLR4/MyD88/NF-κB pathway proteins were determined using Western blot ***:MiR-3124-5p is overexpressed in clinical tissues and cells of ***-3124-5p was dramatically enriched in CAF-derived *** experiments revealed that CAFs delivered miR-3124-5p into NSCLC cells via exosomes,stimulating cancer cell ***-3124-5p acted as a sponge to negatively regulate TOLLIP expression,which activated the TLR4/MyD88/NF-κB axis to promote the occurrence and development of *** salvage tests were performed to determine whether CAF-exosome-derived miR-3124-5p plays a pro-cancer role in NSCLC by affecting the TOLLIP signalling ***:These results provide an interesting direction for the diagnosis and therapy of NSCLC.

关键词： Non-small cell lung cancer(NSCLC) Cancer-associated fibroblasts(CAFs) Exosomes miR-3124-5p Toll-interacting protein(TOLLIP)

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling liu Biao Meng tao Chen Yu han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

基于SPH方法的活塞环岸润滑油输运的数值研究

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工程热物理学报 2021年第5期42卷 1238-1243页

作者：李海桥刘汉涛中北大学能源动力工程学院太原030051

活塞环岸润滑油的输运过程是一个典型的复杂多相流问题,该过程对柴油机动力性和排放等性能有显著影响。应用N-S方程描述润滑油的输运过程,并对润滑油输运的物理模型和初始条件进行简化,首次利用SPH方法求解活塞环岸上润滑油膜的状态。... 详细信息

活塞环岸润滑油的输运过程是一个典型的复杂多相流问题,该过程对柴油机动力性和排放等性能有显著影响。应用N-S方程描述润滑油的输运过程,并对润滑油输运的物理模型和初始条件进行简化,首次利用SPH方法求解活塞环岸上润滑油膜的状态。研究表明SPH方法可以准确描述润滑油输运过程中的各种复杂状态,能对各个部位润滑油膜的厚度及各个时刻可用润滑油量进行预测。为研究和预测柴油机润滑油膜的输运过程提供了一种新的思路和方法。

关键词：活塞环岸光滑粒子动力学(SPH) 润滑油膜 N-S方程

Effect of the RNA5 component on pathogenicity of beet necrotic yellow vein virus

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Chinese Science Bulletin 2003年第8期48卷 796-799页

作者： liu tao, han Chenggui, LI Dawei, CAI Zhunan, YU Jialin & liu Yi State Key Laboratory for Agrobiotechnology and College of Biological Science, China Agricultural University, Beijing 100094, China Correspondence should be addressed to Yu Jialin (e-mail: bnyvv@public. ***) State Key Laboratory for Agrobiotechnology and College of Biological Science China Agricultural University Beijing China

The transcripts of beet necrotic yellow virus RNA5 were prepared from the cloned cDNA in a bacterio-phage T7 in vitro run-off transcription system. The RNA5 transcripts and RNAs extracted from two BNYVV mutants, Hu0 containing RNA1, 2 and Hu3 containing RNA1, 2, 3 respectively, were co-inoculated to Tetragonia expansa and sugar beet seedlings. The results indicated that the virus infections and accumulation in the hosts could be improved by presence of RNA5. Cooperating with RNA3, the RNA5 seems to cause more severe symptom and yield losses in sugar beet. These results suggest that, in addition of RNA3, BNYVV RNA5 is another important factor associated with the virus pathogenicity.

关键词： RNA 致病性甜菜 BNYVV 核糖核酸

Escobar-Lichnerowicz-Reilly type eigenvalue estimate for the weighted p-Laplacian on manifolds with integral Ricci curvature

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Acta Mathematica Sinica,English Series 2025年

作者： Yong tao liu School of Mathematics and Statistics Ningxia University

Under the assumption of integral m-Bakry-émery Ricci curvature, we give an Escobar-LichnerowiczReilly type eigenvalue estimate for the weighted p-Laplacian on compact smooth metric measure spaces with or without boundaries. This conclusion is a generalization and improvement of Wang-Li’s result in the case of integral Bakry-émery Ricci curvature, and of Seto-Wei’s one to the compact metric measure space setting. Our main tools are the weighted p-Bochner formula and the weighted p-Reilly formula.

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Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 49-64页

作者： WANG Xin SHEN Dejian tao Sijie liu Ruixin WU Shengxing College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

关键词： tricalcium silicate simulation method chloride diffusion coefficient pore solution

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou Cheng Qing Zhao Mengjie tao Jijun Du Xingxi Huang Chengjun liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction