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UNIFORM ERROR BOUNDS OF A CONSERVATIVE COMPACT FINITE DIFFERENCE METHOD FOR THE QUANTUM ZAKHAROV SYSTEM IN THE suBSONIC LIMIT REGIME

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Journal of Computational Mathematics 2024年第1期42卷 289-312页

作者： Gengen Zhang Chunmei su School of Mathematics and Statistics Yunnan UniversityKunming 650504China Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China

In this paper,we consider a uniformly accurate compact finite difference method to solve the quantum Zakharov system(QZS)with a dimensionless parameter 0<ε≤1,which is inversely proportional to the acoustic *** the s... 详细信息

In this paper,we consider a uniformly accurate compact finite difference method to solve the quantum Zakharov system(QZS)with a dimensionless parameter 0subsonic limit regime,i.e.,when 0sults are reported to verify the error behavior.

关键词： Quantum Zakharov system subsonic limit Compact finite difference method Uniformly accurate Error estimate

Hybrid Block Diagonalization Precoding for Multi-User Weighted sum-Rate Maximization

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China Communications 2024年第8期21卷 127-141页

作者： su Xiaofeng Jiang Yi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China

This paper studies large-scale multi-input multi-output(MIMO)orthogonal frequency division multiplexing(OFDM)communications in a broadband frequency-selective channel,where a massive MIMO base station(BS)communicates with multiple users equipped with *** develop a hybrid precoding design to maximize the weighted sum-rate(WSR)of the users by optimizing the digital and the analog precoders *** the digital part,we employ block-diagonalization to eliminate inter-user interference and apply water-filling power allocation to maximize the *** the analog part,the optimization of the PSN is formulated as an unconstrained problem,which can be efficiently solved by a gradient descent *** results show that the proposed block-diagonal hybrid precoding algorithm can outperform the existing works.

关键词： block-diagonal gradient descent hybrid precoding iterative optimization MIMO-OFDM multi-user water-filling power allocation weighted sum-rate maximization

A real-world study of the differences in Traditional Chinese Medicine diagnosis and treatment rules for coronavirus disease 2019 between Northern and Southern China

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Journal of Traditional Chinese Medicine 2024年第4期44卷 822-829页

作者： su Rui su Youzhu WANG Shuo FAN Jie LIU Qingquan LIU Mifeng Department of infectious diseases Capital Medical University Beijing Hospital of Traditional Chinese MedicineBeijing 100010China

OBJECTIVE:To explore the differences in Traditional Chinese Medicine(TCM)diagnosis and treatment rules for coronavirus disease 2019(COVID-19)between Northern and Southern China based on the real-world data from 982 COVID-19 ***:All consecutive cases of COVID-19 admitted to the TCM department of designated COVID-19 hospitals in eight provinces and cities were retrospectively *** were divided into a Northern and a Southern group according to the location of the admitting *** symptoms,syndrome elements,syndrome distribution and herbal treatments were *** core prescriptions were extracted using the multiscale backbone-based network comparison algorithm(msbNC).REsuLTS:The distribution of syndrome elements showed that dampness was common in Northern and Southern China,wind and heat were more often present in the South,while fire toxin and spleen deficiency were more often encountered in the *** distribution of syndromes showed that the South was dominated by heat dampness accumulating in the lung(55.69%),while the North was dominated by dampness-toxin stagnating in the lung(44.90%).The results of core prescription mining showed that dispelling dampness,dispersing wind,clearing heat and strengthening spleen were the common treatment methods in Northern and Southern *** mild cases,Jinyinhua(Flos Lonicerae)and Lianqiao(Fructus Forsythiae suspensae)were often used in the South to clear heat and relieve exterior symptoms,while Chaihu(Radix Bupleuri Chinensis)and Huangqin(Radix Scutellariae Baicalensis)were often used in the North to relieve muscles by expelling *** moderate cases,Chaihu(Radix Bupleuri Chinensis),Qinghao(Herba Artemisiae Annuae),and Shigao(Gypsum Fibrosum)were often used to clear heat of Tri-jiao Channel and stomach in the South,while Fuling(Poria),Chenpi(Pericarpium Citri Reticulatae),and Dangshen(Radix Codonopsis)were often used to invigorate spleen and remove dampness in the *** severe cases

关键词： COVID-19 medicine,Chinese traditional North-South difference core prescription syndrome retrospective studies

Parity-dependent skin effects and topological properties in the multilayer nonreciprocal su−Schrieffer−Heeger structures

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Frontiers of physics 2024年第3期19卷 115-133页

作者： Jia-Rui Li Cui Jiang Han su Di Qi Lian-Lian Zhang Wei-Jiang Gong College of Sciences Northeastern UniversityShenyang 110819China Basic Department Shenyang Institute of EngineeringShenyang 110136China

We concentrate on the skin effects and topological properties in the multilayer non-Hermitian su−Schrieffer−Heeger (SSH) structure, by taking into account the nonreciprocal couplings between the different sublattices in the unit cells. Following the detailed demonstration of the theoretical method, we find that in this system, the skin effects and topological phase transitions induced by nonreciprocal couplings display the apparent parity effect, following the increase of the layer number of this SSH structure. On the one hand, the skin effect is determined by the parity of the layer number of this SSH system, as well as the parity of the band index of the bulk states. On the other hand, for the topological edge modes, such an interesting parity effect can also be observed clearly. Next, when the parameter disorders are taken into account, the zero-energy edge modes in the odd-layer structures tend to be more robust, whereas the other edge modes are easy to be destroyed. In view of these results, it can be ascertained that the findings in this work promote to understand the influences of nonreciprocal couplings on the skin effects and topological properties in the multilayer SSH lattices.

关键词： multilayer SSH lattice nonreciprocal couplings band structure skin effect

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纳米流体阻尼器对高桩码头抗震性能的影响

河海大学学报（自然科学版） 2024年第4期52卷 85-94页

作者：王远欣苏雷孙岳霆凌贤长青岛理工大学土木工程学院山东青岛266000 伯明翰大学工程学院西米德兰兹郡伯明翰B152TT 哈尔滨工业大学土木工程学院黑龙江哈尔滨150090

为了研究纳米流体材料在降低高桩码头的动力响应、减轻码头震害领域的应用潜力,基于开源有限元计算平台OpenSees,建立了加入阻尼器的高桩码头二维有限元模型,对比分析了传统黏滞阻尼器和纳米流体阻尼器对高桩码头抗震性能的影响,评估了... 详细信息

为了研究纳米流体材料在降低高桩码头的动力响应、减轻码头震害领域的应用潜力,基于开源有限元计算平台OpenSees,建立了加入阻尼器的高桩码头二维有限元模型,对比分析了传统黏滞阻尼器和纳米流体阻尼器对高桩码头抗震性能的影响,评估了纳米流体材料对高桩码头的减震效果。结果表明:纳米流体阻尼器比黏滞阻尼器具有更好的限制桩顶侧向变形的能力;相比于黏滞阻尼器,纳米流体阻尼器可以更好地降低陆侧桩的桩顶曲率;加入纳米流体阻尼器的码头桩顶耗能小于加入黏滞阻尼器的码头桩顶耗能。

关键词：纳米流体材料黏滞阻尼器高桩码头地震响应

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Friction and Deformation Behavior of Human Skin During Robotic Sliding Massage Operation

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Journal of Bionic Engineering 2024年第4期21卷 1892-1904页

作者： Jingmei Zhai Rixing Li Ziqing su School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510000China

This study investigates the friction and deformation behavior of the skin in contact with a rigid massage ball and its influencing *** and stretching experiments were conducted using a collaborative robot experimental *** experiments encompassed a loading normal force range of 2 N to 18 N and a sliding speed range of 10 mm/s to 20 mm/*** friction response curve exhibits two different stages:static stick state and dynamic stick-slip stage,both of which have been mathematically *** analyzing the experimental data,we analyzed the effects of elastic modulus,sliding speed and normal loading force on skin tangential friction and tensile *** results indicate that as the normal load increases,both friction and deformation exhibit an ***,they decrease with an increase in elastic ***,while deformation diminishes with higher sliding speed,friction force remains relatively unaffected by *** observation can be attributed to the strain rate sensitivity resulting from the viscoelastic characteristics of the skin under substantial *** study advances the understanding of friction and deformation behavior during skin friction,offering valuable insights to enhance the operational comfort of massage robots.

关键词： Human skin Friction sliding Deformation Robotic massage Stereo image

Dynamic characteristics of multi-span spinning beams with elastic constraints under an axial compressive force

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 295-310页

作者： Xiaodong GUO Zhu su Lifeng WANG State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is *** displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the *** exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange *** efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other *** effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are *** results show that the present method can freely simulate any boundary constraints without modifying the solution *** elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of *** an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.

关键词： multi-span spinning beam elastic constraint improved Fourier series free vibration semi-analytical solution

H_(∞)/Passive Synchronization of Semi-Markov Jump Neural Networks subject to Hybrid Attacks via an Activation Function Division Approach

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Journal of Systems Science & Complexity 2024年第3期37卷 1023-1036页

作者： ZHANG Ziwei SHEN Hao su Lei School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan 243002China Anhui Province Key Laboratory of Special Heavy Load Robot and School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan243002China

In this work,an H_(∞)/passive-based secure synchronization control problem is investigated for continuous-time semi-Markov neural networks subject to hybrid attacks,in which hybrid attacks are the combinations of denial-of-service attacks and deception attacks,and they are described by two groups of independent Bernoulli *** this foundation,via the Lyapunov stability theory and linear matrix inequality technology,the H_(∞)/passive-based performance criteria for semi-Markov jump neural networks are ***,an activation function division approach for neural networks is adopted to further reduce the conservatism of the ***,a simulation example is provided to verify the validity and feasibility of the proposed method.

关键词： Activation function division approach deception attacks denial-of-service attacks H_(∞)/passive synchronization semi-Markov jump neural networks

Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei

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Journal of Forestry Research 2024年第1期35卷 12-28页

作者： Shicheng su Nianqing Jin Xiaoli Wei College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China Institute for Forest Resources and Environment of Guizhou Guizhou UniversityGuiyang 550025People’s Republic of China

Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the *** this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei *** canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following *** improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light *** the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral *** photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light *** a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal *** a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of *** seedlings,and a reduction increased light absorption and use capacity and height:diameter *** growth advantage transformed from diameter to height,enabling seedlings to access more *** findings suggest that the regeneration of shade-tolerant species such as *** could be enhanced if a targeted approach to thinning based on stand type was adopted.

关键词： Thinning Understory light environment Phoebe bournei Photosynthetic performance Growth performance