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老年人群中开展结核病主动发现的研究进展

中国防痨杂志 2025年第1期47卷 96-101页

作者：孙丹雨辰刘宇红首都医科大学附属北京胸科医院/中国疾病预防控制中心结核病防治临床中心北京101149

结核病仍然是危害全球公共健康的重大传染病,其中老年人群的结核病负担日益严峻。我国是结核病高负担国家之一,且近年来老龄化趋势严重,因此,老年人群的结核病防治对终结结核病的进程至关重要,特别是老年人群患者的发现工作。笔者查阅... 详细信息

结核病仍然是危害全球公共健康的重大传染病,其中老年人群的结核病负担日益严峻。我国是结核病高负担国家之一,且近年来老龄化趋势严重,因此,老年人群的结核病防治对终结结核病的进程至关重要,特别是老年人群患者的发现工作。笔者查阅并总结国内外针对老年人群主动筛查的研究文献,对老年人群结核病流行病学现状、主动筛查的开展方式、筛查效果的影响因素及存在的挑战进行综述,旨在阐述在老年人群中开展结核病主动发现策略的重要性和必要性。

关键词：结核老年人人群监测综述

Understanding and design of metallic alloys guided by phase-field simulations

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npj Computational Materials 2023年第1期9卷 1377-1401页

作者： yuhong Zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083PR China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education for High-performance Al and Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051PR China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004PR China

Phase-field method(PFM)has become a mainstream computational method for predicting the evolution of nano and mesoscopic microstructures and properties during materials *** paper briefly reviews latest progresses in applying PFM to understanding the thermodynamic driving forces and mechanisms underlying microstructure evolution in metallic materials and related processes,including casting,aging,deformation,additive manufacturing,and defects,*** on designing alloys by integrating PFM with constitutive relations and machine *** examples are presented to demonstrate the potential of integrated PFM in discovering new multi-scale phenomena and high-performance *** article ends with prospects for promising research directions.

关键词： alloys microstructure metallic

On Connected Graphs with Distance Eigenvalue-1 of Multiplicity at Least n-4

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Algebra Colloquium 2023年第4期30卷 639-648页

作者： yuhong Yang Institute of Signal Processing and Machine Learning College of ScienceTianjin University of TechnologyTianjin 300384China College of Mathematics and System Science Xinjiang UniversityUrumqi 830046China

Let G_(n)([-1]^(i))denote the set of all connected graphs on n vertices having distance eigenvalue-1 of multiplicity *** using the distribution of the third largest distance eigenvalue and the second least distance eigenvalue of a connected graph,in this paper we completely characterize the graphs in G_(n)([-1]^(i)),where i=n-1,n-2,n-3 or n-4.

关键词： distance hereditary graph distance spectrum canonical graph primitive graph

Numerical investigation on fluid forces of piggyback circular cylinders in tandem arrangement at low Reynolds numbers

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Acta Mechanica Sinica 2021年第4期37卷 599-612,I0002页

作者： Linfeng Chen yuhong Dong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyJiangsu 212003China Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering Scienceand Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai 200072China

Numerical simulations of flows past the piggyback circular cylinders in tandem arrangement are performed by solving the variational multiscale formulation of the incompressible Navier-Stokes equations using in-house finite element method(FEM)*** effects of the gap-spacing-to-diameter(G/D)and the two diameter ratio(d/D)on the flow characteristics and the reductions of the root-mean-square(RMS)drag and lift coefficients are considered for Reynolds numbers(Res)are 100 and *** validation shows the fluid force coefficients obtained by the in-house FEM codes are in good agreement with the results in the existing *** obtained results show that,with a proper placement of the smaller cylinder(d/D=0.2)behind the larger cylinder,the RMS drag and lift coefficients largely decrease compared to those of the single circular *** d/D=0.2,the largest reductions of the RMS lift coefficient of the larger cylinder and the RMS total lift coefficient appear at G/D=1.2 as Re=100 and at G/D=1.0 as Re=*** is observed that the proper placement of the smaller cylinder causes the surrounding vorticity to take opposite sign with the vorticity in the outer region so as to suppress and postpone the vortex shedding in the wake,and that the different positions of the vortex shedding at two Res cause that the largest reductions of the RMS lift coefficient of the larger cylinder and the RMS total lift coefficient appear at different G/D as Re is *** d/D varies,the variation of the RMS total lift coefficient behaves differently at two *** decreases with J/D increasing at Re=100,while it no longer monotonously varies with J/D,but reaches a minimum in the considered range of d/D at Re=***,the larger d/D results in stronger suppression and postponement of the vortex shedding in the wake.

关键词： Piggyback circular cylinders Hydrodynamic forces Vortex shedding Finite element method Variational multiscale method

Superlubricity achieved with two-dimensional nano-additives to liquid lubricants

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Friction 2020年第6期8卷 1007-1024页

作者： Hongdong WANG yuhong LIU State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

The topic of superlubricity is attracting considerable interest around the world while humanity is facing an energy *** various liquid superlubricity systems can be commonly achieved on the macroscale in ambient conditions,it is considered an effective solution to reduce unnecessary energy and material ***,certain practical problems such as low load-bearing pressure,dependence on hydrogen ions,and relatively long running-in processes still limit its widespread ***-dimensional(2D)nano-additives with ultrathin longitudinal dimensions can lower the shear resistance between sliding solid surfaces,and thus further optimize the applied *** this review,the latest studies on 2D nano-additives with a combination of various water-based lubricants in the state of superlubricity are reported,typically including black phosphorus(BP),graphene oxide(GO),and layered double *** the sliding process,composite lubricants effectively improved the load capacity(up to 600 MPa),reduced wear,and accelerated the running-in period(within 1,000 s)of the liquid superlubricity *** macromechanical experiments and microscopic tests are conducted to precisely analyze various interactions at the interfaces of the nano-additives and solid *** interactions can be described as tribochemical reactions,physical protection,and adsorption enhancement,and improved wear *** review provides better guidance for applying 2D nanomaterials in liquid superlubricity systems.

关键词： superlubricity two-dimensional(2D)nanomaterial lubricant additive water-based tribological property

Experimental Study on Molecular Arrangement of Nanoscale Lubricant Films——A Review

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 896-903页

作者： ZHANG Shaohua LIU yuhong State Key Laboratory of Tribology Tsinghua University

In order to understand lubrication mechanism at the nanoscale, researchers have used many physical experimental approaches, such as surface force apparatus, atomic force microscopy and ball-on-disk tribometer. The results show that the variation rules of the friction force, film thicknessand viscosity of the lubricant at the nanoscale are different from elastohydrodynamic lubrication （EHL）. It is speculated that these differences are attributed to the special arrangement of the molecules at the nanoscale. However, it is difficult to obtain the molecular orientation and distribution directly from the lubricant molecules in these experiments. In recent years, more and more attention has been paid to use new techniques to overcome the shortcomings of traditional experiments, including various spectral methods. The most representative achievements in the experimental research of molecular arrangement are reviewed in this paper： The change of film structure of a liquid crystal under confinement has been obtained using X-ray method. The molecular orientation change of lubricant films has been observed using absorption spectroscopy. Infrared spectroscopy has been used to measure the anisotropy of molecular orientation in the contact region when the lubricant film thickness is reduced to a few tens of nanometers. In situ Raman spectroscopy has been performed to measure the molecular orientation of the lubricant film semi-quantitatively. These results prove that confinement and shear in the contact region can change the arrangement of lubricant molecules. As a result, the lubrication characteristics are affected. The shortages of these works are also discussed based on practicable results. Further work is needed to separate the information of the solid-liquid interface from the bulk liquid film.

关键词： nano-scale lubricating film in situ measurement molecular arrangement

Analysis of Stability and Large Deflection Buckle of Rolled Strip by Third Power B-Spline Function Method

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Journal of Iron and Steel Research International 1997年第2期4卷 24-28页

作者： Bian yuhong Yanshan University

A new method——the third power B-spline function method is developed to analyse the stability and the buckle of rolled strip under residual *** large deflection theory of thin plate is used to calculate the buckle of rolled strip and criterion of critical buckle is *** computed results tally with those of experiment well,which provides theoretical basis and method for developing the mathematical model of flatness control.

关键词： flatness control large deflection buckle critical buckle third power B-spline function

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Effect of particles on turbulent thermal field of channel flow with different Prandtl numbers

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 987-998页

作者： Caixi LIU yuhong DONG Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

The direct numerical simulation （DNS） of heat transfer in a fully developed non-isothermal particle-laden turbulent channel flow is performed. The focus of this paper is on the modulation of the particles on turbulent thermal statistics in the particle-laden flow with three Prandtl numbers （Pτ = 0.71, 1.5, and 3.0） and a shear Reynolds number （Reτ = 180）. Some typical thermal statistics, including normalized mean temperature and their fluctuations, turbulent heat fluxes, Nusselt number and so on, are analyzed. The results show that the particles have less effects on turbulent thermal fields with the increase of Prandtl number. Two reasons can explain this. First, the correlation between fluid thermal field and velocity field decreases as the Prandtl number increases, and the modulation of turbulent velocity field induced by the particles has less influence on the turbulent thermal field. Second, the heat exchange between turbulence and particles decreases for the particle-laden flow with the larger Prandtl number, and the thermal feedback of the particles to turbulence becomes weak.

关键词： direct numerical simulation (DNS) Prandtl number particle thermal statistic channel flow

Challenges and Opportunities of Sub-6 GHz Integrated Sensing and Communications for 5G-Advanced and Beyond

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Chinese Journal of Electronics 2024年第2期33卷 323-325页

作者： yuhong HUANG China Mobile Research Institute China Mobile Communications Group Co. Ltd

The integrated sensing and communications(ISAC) technology has been perceived as a key feature of5G-Advanced and beyond mobile communication networks. Compared with sensing in millimeter-wave bands, sensing at sub-6 GHz band is an exceptional incentive to promote the industrialization process of ISAC due to its incomparable advantages in industrial development, especially for intelligent transportation and smart drone networks. This paper elaborates on the top challenges of sub-6 GHz ISAC technologies, as well as the potential solutions to improve the sensing capability.

关键词： Electric potential Millimeter wave technology Transportation Mobile communication Sensors Millimeter wave communication Drones